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1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Daniel Hartmeier
5  * Copyright (c) 2002 - 2008 Henning Brauer
6  * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  *
13  *    - Redistributions of source code must retain the above copyright
14  *      notice, this list of conditions and the following disclaimer.
15  *    - Redistributions in binary form must reproduce the above
16  *      copyright notice, this list of conditions and the following
17  *      disclaimer in the documentation and/or other materials provided
18  *      with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
28  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  *
33  * Effort sponsored in part by the Defense Advanced Research Projects
34  * Agency (DARPA) and Air Force Research Laboratory, Air Force
35  * Materiel Command, USAF, under agreement number F30602-01-2-0537.
36  *
37  *      $OpenBSD: pf.c,v 1.634 2009/02/27 12:37:45 henning Exp $
38  */
39
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42
43 #include "opt_inet.h"
44 #include "opt_inet6.h"
45 #include "opt_bpf.h"
46 #include "opt_pf.h"
47
48 #include <sys/param.h>
49 #include <sys/bus.h>
50 #include <sys/endian.h>
51 #include <sys/hash.h>
52 #include <sys/interrupt.h>
53 #include <sys/kernel.h>
54 #include <sys/kthread.h>
55 #include <sys/limits.h>
56 #include <sys/mbuf.h>
57 #include <sys/md5.h>
58 #include <sys/random.h>
59 #include <sys/refcount.h>
60 #include <sys/socket.h>
61 #include <sys/sysctl.h>
62 #include <sys/taskqueue.h>
63 #include <sys/ucred.h>
64
65 #include <net/if.h>
66 #include <net/if_var.h>
67 #include <net/if_types.h>
68 #include <net/if_vlan_var.h>
69 #include <net/route.h>
70 #include <net/radix_mpath.h>
71 #include <net/vnet.h>
72
73 #include <net/pfil.h>
74 #include <net/pfvar.h>
75 #include <net/if_pflog.h>
76 #include <net/if_pfsync.h>
77
78 #include <netinet/in_pcb.h>
79 #include <netinet/in_var.h>
80 #include <netinet/in_fib.h>
81 #include <netinet/ip.h>
82 #include <netinet/ip_fw.h>
83 #include <netinet/ip_icmp.h>
84 #include <netinet/icmp_var.h>
85 #include <netinet/ip_var.h>
86 #include <netinet/tcp.h>
87 #include <netinet/tcp_fsm.h>
88 #include <netinet/tcp_seq.h>
89 #include <netinet/tcp_timer.h>
90 #include <netinet/tcp_var.h>
91 #include <netinet/udp.h>
92 #include <netinet/udp_var.h>
93
94 #include <netpfil/ipfw/ip_fw_private.h> /* XXX: only for DIR_IN/DIR_OUT */
95
96 #ifdef INET6
97 #include <netinet/ip6.h>
98 #include <netinet/icmp6.h>
99 #include <netinet6/nd6.h>
100 #include <netinet6/ip6_var.h>
101 #include <netinet6/in6_pcb.h>
102 #include <netinet6/in6_fib.h>
103 #include <netinet6/scope6_var.h>
104 #endif /* INET6 */
105
106 #include <machine/in_cksum.h>
107 #include <security/mac/mac_framework.h>
108
109 #define DPFPRINTF(n, x) if (V_pf_status.debug >= (n)) printf x
110
111 /*
112  * Global variables
113  */
114
115 /* state tables */
116 VNET_DEFINE(struct pf_altqqueue,         pf_altqs[2]);
117 VNET_DEFINE(struct pf_palist,            pf_pabuf);
118 VNET_DEFINE(struct pf_altqqueue *,       pf_altqs_active);
119 VNET_DEFINE(struct pf_altqqueue *,       pf_altqs_inactive);
120 VNET_DEFINE(struct pf_kstatus,           pf_status);
121
122 VNET_DEFINE(u_int32_t,                   ticket_altqs_active);
123 VNET_DEFINE(u_int32_t,                   ticket_altqs_inactive);
124 VNET_DEFINE(int,                         altqs_inactive_open);
125 VNET_DEFINE(u_int32_t,                   ticket_pabuf);
126
127 VNET_DEFINE(MD5_CTX,                     pf_tcp_secret_ctx);
128 #define V_pf_tcp_secret_ctx              VNET(pf_tcp_secret_ctx)
129 VNET_DEFINE(u_char,                      pf_tcp_secret[16]);
130 #define V_pf_tcp_secret                  VNET(pf_tcp_secret)
131 VNET_DEFINE(int,                         pf_tcp_secret_init);
132 #define V_pf_tcp_secret_init             VNET(pf_tcp_secret_init)
133 VNET_DEFINE(int,                         pf_tcp_iss_off);
134 #define V_pf_tcp_iss_off                 VNET(pf_tcp_iss_off)
135 VNET_DECLARE(int,                        pf_vnet_active);
136 #define V_pf_vnet_active                 VNET(pf_vnet_active)
137
138 static VNET_DEFINE(uint32_t, pf_purge_idx);
139 #define V_pf_purge_idx  VNET(pf_purge_idx)
140
141 /*
142  * Queue for pf_intr() sends.
143  */
144 static MALLOC_DEFINE(M_PFTEMP, "pf_temp", "pf(4) temporary allocations");
145 struct pf_send_entry {
146         STAILQ_ENTRY(pf_send_entry)     pfse_next;
147         struct mbuf                     *pfse_m;
148         enum {
149                 PFSE_IP,
150                 PFSE_IP6,
151                 PFSE_ICMP,
152                 PFSE_ICMP6,
153         }                               pfse_type;
154         struct {
155                 int             type;
156                 int             code;
157                 int             mtu;
158         } icmpopts;
159 };
160
161 STAILQ_HEAD(pf_send_head, pf_send_entry);
162 static VNET_DEFINE(struct pf_send_head, pf_sendqueue);
163 #define V_pf_sendqueue  VNET(pf_sendqueue)
164
165 static struct mtx pf_sendqueue_mtx;
166 MTX_SYSINIT(pf_sendqueue_mtx, &pf_sendqueue_mtx, "pf send queue", MTX_DEF);
167 #define PF_SENDQ_LOCK()         mtx_lock(&pf_sendqueue_mtx)
168 #define PF_SENDQ_UNLOCK()       mtx_unlock(&pf_sendqueue_mtx)
169
170 /*
171  * Queue for pf_overload_task() tasks.
172  */
173 struct pf_overload_entry {
174         SLIST_ENTRY(pf_overload_entry)  next;
175         struct pf_addr                  addr;
176         sa_family_t                     af;
177         uint8_t                         dir;
178         struct pf_rule                  *rule;
179 };
180
181 SLIST_HEAD(pf_overload_head, pf_overload_entry);
182 static VNET_DEFINE(struct pf_overload_head, pf_overloadqueue);
183 #define V_pf_overloadqueue      VNET(pf_overloadqueue)
184 static VNET_DEFINE(struct task, pf_overloadtask);
185 #define V_pf_overloadtask       VNET(pf_overloadtask)
186
187 static struct mtx pf_overloadqueue_mtx;
188 MTX_SYSINIT(pf_overloadqueue_mtx, &pf_overloadqueue_mtx,
189     "pf overload/flush queue", MTX_DEF);
190 #define PF_OVERLOADQ_LOCK()     mtx_lock(&pf_overloadqueue_mtx)
191 #define PF_OVERLOADQ_UNLOCK()   mtx_unlock(&pf_overloadqueue_mtx)
192
193 VNET_DEFINE(struct pf_rulequeue, pf_unlinked_rules);
194 struct mtx pf_unlnkdrules_mtx;
195 MTX_SYSINIT(pf_unlnkdrules_mtx, &pf_unlnkdrules_mtx, "pf unlinked rules",
196     MTX_DEF);
197
198 static VNET_DEFINE(uma_zone_t,  pf_sources_z);
199 #define V_pf_sources_z  VNET(pf_sources_z)
200 uma_zone_t              pf_mtag_z;
201 VNET_DEFINE(uma_zone_t,  pf_state_z);
202 VNET_DEFINE(uma_zone_t,  pf_state_key_z);
203
204 VNET_DEFINE(uint64_t, pf_stateid[MAXCPU]);
205 #define PFID_CPUBITS    8
206 #define PFID_CPUSHIFT   (sizeof(uint64_t) * NBBY - PFID_CPUBITS)
207 #define PFID_CPUMASK    ((uint64_t)((1 << PFID_CPUBITS) - 1) << PFID_CPUSHIFT)
208 #define PFID_MAXID      (~PFID_CPUMASK)
209 CTASSERT((1 << PFID_CPUBITS) >= MAXCPU);
210
211 static void              pf_src_tree_remove_state(struct pf_state *);
212 static void              pf_init_threshold(struct pf_threshold *, u_int32_t,
213                             u_int32_t);
214 static void              pf_add_threshold(struct pf_threshold *);
215 static int               pf_check_threshold(struct pf_threshold *);
216
217 static void              pf_change_ap(struct mbuf *, struct pf_addr *, u_int16_t *,
218                             u_int16_t *, u_int16_t *, struct pf_addr *,
219                             u_int16_t, u_int8_t, sa_family_t);
220 static int               pf_modulate_sack(struct mbuf *, int, struct pf_pdesc *,
221                             struct tcphdr *, struct pf_state_peer *);
222 static void              pf_change_icmp(struct pf_addr *, u_int16_t *,
223                             struct pf_addr *, struct pf_addr *, u_int16_t,
224                             u_int16_t *, u_int16_t *, u_int16_t *,
225                             u_int16_t *, u_int8_t, sa_family_t);
226 static void              pf_send_tcp(struct mbuf *,
227                             const struct pf_rule *, sa_family_t,
228                             const struct pf_addr *, const struct pf_addr *,
229                             u_int16_t, u_int16_t, u_int32_t, u_int32_t,
230                             u_int8_t, u_int16_t, u_int16_t, u_int8_t, int,
231                             u_int16_t, struct ifnet *);
232 static void              pf_send_icmp(struct mbuf *, u_int8_t, u_int8_t,
233                             sa_family_t, struct pf_rule *);
234 static void              pf_detach_state(struct pf_state *);
235 static int               pf_state_key_attach(struct pf_state_key *,
236                             struct pf_state_key *, struct pf_state *);
237 static void              pf_state_key_detach(struct pf_state *, int);
238 static int               pf_state_key_ctor(void *, int, void *, int);
239 static u_int32_t         pf_tcp_iss(struct pf_pdesc *);
240 static int               pf_test_rule(struct pf_rule **, struct pf_state **,
241                             int, struct pfi_kif *, struct mbuf *, int,
242                             struct pf_pdesc *, struct pf_rule **,
243                             struct pf_ruleset **, struct inpcb *);
244 static int               pf_create_state(struct pf_rule *, struct pf_rule *,
245                             struct pf_rule *, struct pf_pdesc *,
246                             struct pf_src_node *, struct pf_state_key *,
247                             struct pf_state_key *, struct mbuf *, int,
248                             u_int16_t, u_int16_t, int *, struct pfi_kif *,
249                             struct pf_state **, int, u_int16_t, u_int16_t,
250                             int);
251 static int               pf_test_fragment(struct pf_rule **, int,
252                             struct pfi_kif *, struct mbuf *, void *,
253                             struct pf_pdesc *, struct pf_rule **,
254                             struct pf_ruleset **);
255 static int               pf_tcp_track_full(struct pf_state_peer *,
256                             struct pf_state_peer *, struct pf_state **,
257                             struct pfi_kif *, struct mbuf *, int,
258                             struct pf_pdesc *, u_short *, int *);
259 static int               pf_tcp_track_sloppy(struct pf_state_peer *,
260                             struct pf_state_peer *, struct pf_state **,
261                             struct pf_pdesc *, u_short *);
262 static int               pf_test_state_tcp(struct pf_state **, int,
263                             struct pfi_kif *, struct mbuf *, int,
264                             void *, struct pf_pdesc *, u_short *);
265 static int               pf_test_state_udp(struct pf_state **, int,
266                             struct pfi_kif *, struct mbuf *, int,
267                             void *, struct pf_pdesc *);
268 static int               pf_test_state_icmp(struct pf_state **, int,
269                             struct pfi_kif *, struct mbuf *, int,
270                             void *, struct pf_pdesc *, u_short *);
271 static int               pf_test_state_other(struct pf_state **, int,
272                             struct pfi_kif *, struct mbuf *, struct pf_pdesc *);
273 static u_int8_t          pf_get_wscale(struct mbuf *, int, u_int16_t,
274                             sa_family_t);
275 static u_int16_t         pf_get_mss(struct mbuf *, int, u_int16_t,
276                             sa_family_t);
277 static u_int16_t         pf_calc_mss(struct pf_addr *, sa_family_t,
278                                 int, u_int16_t);
279 static int               pf_check_proto_cksum(struct mbuf *, int, int,
280                             u_int8_t, sa_family_t);
281 static void              pf_print_state_parts(struct pf_state *,
282                             struct pf_state_key *, struct pf_state_key *);
283 static int               pf_addr_wrap_neq(struct pf_addr_wrap *,
284                             struct pf_addr_wrap *);
285 static struct pf_state  *pf_find_state(struct pfi_kif *,
286                             struct pf_state_key_cmp *, u_int);
287 static int               pf_src_connlimit(struct pf_state **);
288 static void              pf_overload_task(void *v, int pending);
289 static int               pf_insert_src_node(struct pf_src_node **,
290                             struct pf_rule *, struct pf_addr *, sa_family_t);
291 static u_int             pf_purge_expired_states(u_int, int);
292 static void              pf_purge_unlinked_rules(void);
293 static int               pf_mtag_uminit(void *, int, int);
294 static void              pf_mtag_free(struct m_tag *);
295 #ifdef INET
296 static void              pf_route(struct mbuf **, struct pf_rule *, int,
297                             struct ifnet *, struct pf_state *,
298                             struct pf_pdesc *, struct inpcb *);
299 #endif /* INET */
300 #ifdef INET6
301 static void              pf_change_a6(struct pf_addr *, u_int16_t *,
302                             struct pf_addr *, u_int8_t);
303 static void              pf_route6(struct mbuf **, struct pf_rule *, int,
304                             struct ifnet *, struct pf_state *,
305                             struct pf_pdesc *, struct inpcb *);
306 #endif /* INET6 */
307
308 int in4_cksum(struct mbuf *m, u_int8_t nxt, int off, int len);
309
310 extern int pf_end_threads;
311 extern struct proc *pf_purge_proc;
312
313 VNET_DEFINE(struct pf_limit, pf_limits[PF_LIMIT_MAX]);
314
315 #define PACKET_LOOPED(pd)       ((pd)->pf_mtag &&                       \
316                                  (pd)->pf_mtag->flags & PF_PACKET_LOOPED)
317
318 #define STATE_LOOKUP(i, k, d, s, pd)                                    \
319         do {                                                            \
320                 (s) = pf_find_state((i), (k), (d));                     \
321                 if ((s) == NULL)                                        \
322                         return (PF_DROP);                               \
323                 if (PACKET_LOOPED(pd))                                  \
324                         return (PF_PASS);                               \
325                 if ((d) == PF_OUT &&                                    \
326                     (((s)->rule.ptr->rt == PF_ROUTETO &&                \
327                     (s)->rule.ptr->direction == PF_OUT) ||              \
328                     ((s)->rule.ptr->rt == PF_REPLYTO &&                 \
329                     (s)->rule.ptr->direction == PF_IN)) &&              \
330                     (s)->rt_kif != NULL &&                              \
331                     (s)->rt_kif != (i))                                 \
332                         return (PF_PASS);                               \
333         } while (0)
334
335 #define BOUND_IFACE(r, k) \
336         ((r)->rule_flag & PFRULE_IFBOUND) ? (k) : V_pfi_all
337
338 #define STATE_INC_COUNTERS(s)                                           \
339         do {                                                            \
340                 counter_u64_add(s->rule.ptr->states_cur, 1);            \
341                 counter_u64_add(s->rule.ptr->states_tot, 1);            \
342                 if (s->anchor.ptr != NULL) {                            \
343                         counter_u64_add(s->anchor.ptr->states_cur, 1);  \
344                         counter_u64_add(s->anchor.ptr->states_tot, 1);  \
345                 }                                                       \
346                 if (s->nat_rule.ptr != NULL) {                          \
347                         counter_u64_add(s->nat_rule.ptr->states_cur, 1);\
348                         counter_u64_add(s->nat_rule.ptr->states_tot, 1);\
349                 }                                                       \
350         } while (0)
351
352 #define STATE_DEC_COUNTERS(s)                                           \
353         do {                                                            \
354                 if (s->nat_rule.ptr != NULL)                            \
355                         counter_u64_add(s->nat_rule.ptr->states_cur, -1);\
356                 if (s->anchor.ptr != NULL)                              \
357                         counter_u64_add(s->anchor.ptr->states_cur, -1); \
358                 counter_u64_add(s->rule.ptr->states_cur, -1);           \
359         } while (0)
360
361 static MALLOC_DEFINE(M_PFHASH, "pf_hash", "pf(4) hash header structures");
362 VNET_DEFINE(struct pf_keyhash *, pf_keyhash);
363 VNET_DEFINE(struct pf_idhash *, pf_idhash);
364 VNET_DEFINE(struct pf_srchash *, pf_srchash);
365
366 SYSCTL_NODE(_net, OID_AUTO, pf, CTLFLAG_RW, 0, "pf(4)");
367
368 u_long  pf_hashmask;
369 u_long  pf_srchashmask;
370 static u_long   pf_hashsize;
371 static u_long   pf_srchashsize;
372 u_long  pf_ioctl_maxcount = 65535;
373
374 SYSCTL_ULONG(_net_pf, OID_AUTO, states_hashsize, CTLFLAG_RDTUN,
375     &pf_hashsize, 0, "Size of pf(4) states hashtable");
376 SYSCTL_ULONG(_net_pf, OID_AUTO, source_nodes_hashsize, CTLFLAG_RDTUN,
377     &pf_srchashsize, 0, "Size of pf(4) source nodes hashtable");
378 SYSCTL_ULONG(_net_pf, OID_AUTO, request_maxcount, CTLFLAG_RDTUN,
379     &pf_ioctl_maxcount, 0, "Maximum number of tables, addresses, ... in a single ioctl() call");
380
381 VNET_DEFINE(void *, pf_swi_cookie);
382
383 VNET_DEFINE(uint32_t, pf_hashseed);
384 #define V_pf_hashseed   VNET(pf_hashseed)
385
386 int
387 pf_addr_cmp(struct pf_addr *a, struct pf_addr *b, sa_family_t af)
388 {
389
390         switch (af) {
391 #ifdef INET
392         case AF_INET:
393                 if (a->addr32[0] > b->addr32[0])
394                         return (1);
395                 if (a->addr32[0] < b->addr32[0])
396                         return (-1);
397                 break;
398 #endif /* INET */
399 #ifdef INET6
400         case AF_INET6:
401                 if (a->addr32[3] > b->addr32[3])
402                         return (1);
403                 if (a->addr32[3] < b->addr32[3])
404                         return (-1);
405                 if (a->addr32[2] > b->addr32[2])
406                         return (1);
407                 if (a->addr32[2] < b->addr32[2])
408                         return (-1);
409                 if (a->addr32[1] > b->addr32[1])
410                         return (1);
411                 if (a->addr32[1] < b->addr32[1])
412                         return (-1);
413                 if (a->addr32[0] > b->addr32[0])
414                         return (1);
415                 if (a->addr32[0] < b->addr32[0])
416                         return (-1);
417                 break;
418 #endif /* INET6 */
419         default:
420                 panic("%s: unknown address family %u", __func__, af);
421         }
422         return (0);
423 }
424
425 static __inline uint32_t
426 pf_hashkey(struct pf_state_key *sk)
427 {
428         uint32_t h;
429
430         h = murmur3_32_hash32((uint32_t *)sk,
431             sizeof(struct pf_state_key_cmp)/sizeof(uint32_t),
432             V_pf_hashseed);
433
434         return (h & pf_hashmask);
435 }
436
437 static __inline uint32_t
438 pf_hashsrc(struct pf_addr *addr, sa_family_t af)
439 {
440         uint32_t h;
441
442         switch (af) {
443         case AF_INET:
444                 h = murmur3_32_hash32((uint32_t *)&addr->v4,
445                     sizeof(addr->v4)/sizeof(uint32_t), V_pf_hashseed);
446                 break;
447         case AF_INET6:
448                 h = murmur3_32_hash32((uint32_t *)&addr->v6,
449                     sizeof(addr->v6)/sizeof(uint32_t), V_pf_hashseed);
450                 break;
451         default:
452                 panic("%s: unknown address family %u", __func__, af);
453         }
454
455         return (h & pf_srchashmask);
456 }
457
458 #ifdef ALTQ
459 static int
460 pf_state_hash(struct pf_state *s)
461 {
462         u_int32_t hv = (intptr_t)s / sizeof(*s);
463
464         hv ^= crc32(&s->src, sizeof(s->src));
465         hv ^= crc32(&s->dst, sizeof(s->dst));
466         if (hv == 0)
467                 hv = 1;
468         return (hv);
469 }
470 #endif
471
472 #ifdef INET6
473 void
474 pf_addrcpy(struct pf_addr *dst, struct pf_addr *src, sa_family_t af)
475 {
476         switch (af) {
477 #ifdef INET
478         case AF_INET:
479                 dst->addr32[0] = src->addr32[0];
480                 break;
481 #endif /* INET */
482         case AF_INET6:
483                 dst->addr32[0] = src->addr32[0];
484                 dst->addr32[1] = src->addr32[1];
485                 dst->addr32[2] = src->addr32[2];
486                 dst->addr32[3] = src->addr32[3];
487                 break;
488         }
489 }
490 #endif /* INET6 */
491
492 static void
493 pf_init_threshold(struct pf_threshold *threshold,
494     u_int32_t limit, u_int32_t seconds)
495 {
496         threshold->limit = limit * PF_THRESHOLD_MULT;
497         threshold->seconds = seconds;
498         threshold->count = 0;
499         threshold->last = time_uptime;
500 }
501
502 static void
503 pf_add_threshold(struct pf_threshold *threshold)
504 {
505         u_int32_t t = time_uptime, diff = t - threshold->last;
506
507         if (diff >= threshold->seconds)
508                 threshold->count = 0;
509         else
510                 threshold->count -= threshold->count * diff /
511                     threshold->seconds;
512         threshold->count += PF_THRESHOLD_MULT;
513         threshold->last = t;
514 }
515
516 static int
517 pf_check_threshold(struct pf_threshold *threshold)
518 {
519         return (threshold->count > threshold->limit);
520 }
521
522 static int
523 pf_src_connlimit(struct pf_state **state)
524 {
525         struct pf_overload_entry *pfoe;
526         int bad = 0;
527
528         PF_STATE_LOCK_ASSERT(*state);
529
530         (*state)->src_node->conn++;
531         (*state)->src.tcp_est = 1;
532         pf_add_threshold(&(*state)->src_node->conn_rate);
533
534         if ((*state)->rule.ptr->max_src_conn &&
535             (*state)->rule.ptr->max_src_conn <
536             (*state)->src_node->conn) {
537                 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONN], 1);
538                 bad++;
539         }
540
541         if ((*state)->rule.ptr->max_src_conn_rate.limit &&
542             pf_check_threshold(&(*state)->src_node->conn_rate)) {
543                 counter_u64_add(V_pf_status.lcounters[LCNT_SRCCONNRATE], 1);
544                 bad++;
545         }
546
547         if (!bad)
548                 return (0);
549
550         /* Kill this state. */
551         (*state)->timeout = PFTM_PURGE;
552         (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
553
554         if ((*state)->rule.ptr->overload_tbl == NULL)
555                 return (1);
556
557         /* Schedule overloading and flushing task. */
558         pfoe = malloc(sizeof(*pfoe), M_PFTEMP, M_NOWAIT);
559         if (pfoe == NULL)
560                 return (1);     /* too bad :( */
561
562         bcopy(&(*state)->src_node->addr, &pfoe->addr, sizeof(pfoe->addr));
563         pfoe->af = (*state)->key[PF_SK_WIRE]->af;
564         pfoe->rule = (*state)->rule.ptr;
565         pfoe->dir = (*state)->direction;
566         PF_OVERLOADQ_LOCK();
567         SLIST_INSERT_HEAD(&V_pf_overloadqueue, pfoe, next);
568         PF_OVERLOADQ_UNLOCK();
569         taskqueue_enqueue(taskqueue_swi, &V_pf_overloadtask);
570
571         return (1);
572 }
573
574 static void
575 pf_overload_task(void *v, int pending)
576 {
577         struct pf_overload_head queue;
578         struct pfr_addr p;
579         struct pf_overload_entry *pfoe, *pfoe1;
580         uint32_t killed = 0;
581
582         CURVNET_SET((struct vnet *)v);
583
584         PF_OVERLOADQ_LOCK();
585         queue = V_pf_overloadqueue;
586         SLIST_INIT(&V_pf_overloadqueue);
587         PF_OVERLOADQ_UNLOCK();
588
589         bzero(&p, sizeof(p));
590         SLIST_FOREACH(pfoe, &queue, next) {
591                 counter_u64_add(V_pf_status.lcounters[LCNT_OVERLOAD_TABLE], 1);
592                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
593                         printf("%s: blocking address ", __func__);
594                         pf_print_host(&pfoe->addr, 0, pfoe->af);
595                         printf("\n");
596                 }
597
598                 p.pfra_af = pfoe->af;
599                 switch (pfoe->af) {
600 #ifdef INET
601                 case AF_INET:
602                         p.pfra_net = 32;
603                         p.pfra_ip4addr = pfoe->addr.v4;
604                         break;
605 #endif
606 #ifdef INET6
607                 case AF_INET6:
608                         p.pfra_net = 128;
609                         p.pfra_ip6addr = pfoe->addr.v6;
610                         break;
611 #endif
612                 }
613
614                 PF_RULES_WLOCK();
615                 pfr_insert_kentry(pfoe->rule->overload_tbl, &p, time_second);
616                 PF_RULES_WUNLOCK();
617         }
618
619         /*
620          * Remove those entries, that don't need flushing.
621          */
622         SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
623                 if (pfoe->rule->flush == 0) {
624                         SLIST_REMOVE(&queue, pfoe, pf_overload_entry, next);
625                         free(pfoe, M_PFTEMP);
626                 } else
627                         counter_u64_add(
628                             V_pf_status.lcounters[LCNT_OVERLOAD_FLUSH], 1);
629
630         /* If nothing to flush, return. */
631         if (SLIST_EMPTY(&queue)) {
632                 CURVNET_RESTORE();
633                 return;
634         }
635
636         for (int i = 0; i <= pf_hashmask; i++) {
637                 struct pf_idhash *ih = &V_pf_idhash[i];
638                 struct pf_state_key *sk;
639                 struct pf_state *s;
640
641                 PF_HASHROW_LOCK(ih);
642                 LIST_FOREACH(s, &ih->states, entry) {
643                     sk = s->key[PF_SK_WIRE];
644                     SLIST_FOREACH(pfoe, &queue, next)
645                         if (sk->af == pfoe->af &&
646                             ((pfoe->rule->flush & PF_FLUSH_GLOBAL) ||
647                             pfoe->rule == s->rule.ptr) &&
648                             ((pfoe->dir == PF_OUT &&
649                             PF_AEQ(&pfoe->addr, &sk->addr[1], sk->af)) ||
650                             (pfoe->dir == PF_IN &&
651                             PF_AEQ(&pfoe->addr, &sk->addr[0], sk->af)))) {
652                                 s->timeout = PFTM_PURGE;
653                                 s->src.state = s->dst.state = TCPS_CLOSED;
654                                 killed++;
655                         }
656                 }
657                 PF_HASHROW_UNLOCK(ih);
658         }
659         SLIST_FOREACH_SAFE(pfoe, &queue, next, pfoe1)
660                 free(pfoe, M_PFTEMP);
661         if (V_pf_status.debug >= PF_DEBUG_MISC)
662                 printf("%s: %u states killed", __func__, killed);
663
664         CURVNET_RESTORE();
665 }
666
667 /*
668  * Can return locked on failure, so that we can consistently
669  * allocate and insert a new one.
670  */
671 struct pf_src_node *
672 pf_find_src_node(struct pf_addr *src, struct pf_rule *rule, sa_family_t af,
673         int returnlocked)
674 {
675         struct pf_srchash *sh;
676         struct pf_src_node *n;
677
678         counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_SEARCH], 1);
679
680         sh = &V_pf_srchash[pf_hashsrc(src, af)];
681         PF_HASHROW_LOCK(sh);
682         LIST_FOREACH(n, &sh->nodes, entry)
683                 if (n->rule.ptr == rule && n->af == af &&
684                     ((af == AF_INET && n->addr.v4.s_addr == src->v4.s_addr) ||
685                     (af == AF_INET6 && bcmp(&n->addr, src, sizeof(*src)) == 0)))
686                         break;
687         if (n != NULL) {
688                 n->states++;
689                 PF_HASHROW_UNLOCK(sh);
690         } else if (returnlocked == 0)
691                 PF_HASHROW_UNLOCK(sh);
692
693         return (n);
694 }
695
696 static int
697 pf_insert_src_node(struct pf_src_node **sn, struct pf_rule *rule,
698     struct pf_addr *src, sa_family_t af)
699 {
700
701         KASSERT((rule->rule_flag & PFRULE_RULESRCTRACK ||
702             rule->rpool.opts & PF_POOL_STICKYADDR),
703             ("%s for non-tracking rule %p", __func__, rule));
704
705         if (*sn == NULL)
706                 *sn = pf_find_src_node(src, rule, af, 1);
707
708         if (*sn == NULL) {
709                 struct pf_srchash *sh = &V_pf_srchash[pf_hashsrc(src, af)];
710
711                 PF_HASHROW_ASSERT(sh);
712
713                 if (!rule->max_src_nodes ||
714                     counter_u64_fetch(rule->src_nodes) < rule->max_src_nodes)
715                         (*sn) = uma_zalloc(V_pf_sources_z, M_NOWAIT | M_ZERO);
716                 else
717                         counter_u64_add(V_pf_status.lcounters[LCNT_SRCNODES],
718                             1);
719                 if ((*sn) == NULL) {
720                         PF_HASHROW_UNLOCK(sh);
721                         return (-1);
722                 }
723
724                 pf_init_threshold(&(*sn)->conn_rate,
725                     rule->max_src_conn_rate.limit,
726                     rule->max_src_conn_rate.seconds);
727
728                 (*sn)->af = af;
729                 (*sn)->rule.ptr = rule;
730                 PF_ACPY(&(*sn)->addr, src, af);
731                 LIST_INSERT_HEAD(&sh->nodes, *sn, entry);
732                 (*sn)->creation = time_uptime;
733                 (*sn)->ruletype = rule->action;
734                 (*sn)->states = 1;
735                 if ((*sn)->rule.ptr != NULL)
736                         counter_u64_add((*sn)->rule.ptr->src_nodes, 1);
737                 PF_HASHROW_UNLOCK(sh);
738                 counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_INSERT], 1);
739         } else {
740                 if (rule->max_src_states &&
741                     (*sn)->states >= rule->max_src_states) {
742                         counter_u64_add(V_pf_status.lcounters[LCNT_SRCSTATES],
743                             1);
744                         return (-1);
745                 }
746         }
747         return (0);
748 }
749
750 void
751 pf_unlink_src_node(struct pf_src_node *src)
752 {
753
754         PF_HASHROW_ASSERT(&V_pf_srchash[pf_hashsrc(&src->addr, src->af)]);
755         LIST_REMOVE(src, entry);
756         if (src->rule.ptr)
757                 counter_u64_add(src->rule.ptr->src_nodes, -1);
758 }
759
760 u_int
761 pf_free_src_nodes(struct pf_src_node_list *head)
762 {
763         struct pf_src_node *sn, *tmp;
764         u_int count = 0;
765
766         LIST_FOREACH_SAFE(sn, head, entry, tmp) {
767                 uma_zfree(V_pf_sources_z, sn);
768                 count++;
769         }
770
771         counter_u64_add(V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], count);
772
773         return (count);
774 }
775
776 void
777 pf_mtag_initialize()
778 {
779
780         pf_mtag_z = uma_zcreate("pf mtags", sizeof(struct m_tag) +
781             sizeof(struct pf_mtag), NULL, NULL, pf_mtag_uminit, NULL,
782             UMA_ALIGN_PTR, 0);
783 }
784
785 /* Per-vnet data storage structures initialization. */
786 void
787 pf_initialize()
788 {
789         struct pf_keyhash       *kh;
790         struct pf_idhash        *ih;
791         struct pf_srchash       *sh;
792         u_int i;
793
794         if (pf_hashsize == 0 || !powerof2(pf_hashsize))
795                 pf_hashsize = PF_HASHSIZ;
796         if (pf_srchashsize == 0 || !powerof2(pf_srchashsize))
797                 pf_srchashsize = PF_SRCHASHSIZ;
798
799         V_pf_hashseed = arc4random();
800
801         /* States and state keys storage. */
802         V_pf_state_z = uma_zcreate("pf states", sizeof(struct pf_state),
803             NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
804         V_pf_limits[PF_LIMIT_STATES].zone = V_pf_state_z;
805         uma_zone_set_max(V_pf_state_z, PFSTATE_HIWAT);
806         uma_zone_set_warning(V_pf_state_z, "PF states limit reached");
807
808         V_pf_state_key_z = uma_zcreate("pf state keys",
809             sizeof(struct pf_state_key), pf_state_key_ctor, NULL, NULL, NULL,
810             UMA_ALIGN_PTR, 0);
811
812         V_pf_keyhash = mallocarray(pf_hashsize, sizeof(struct pf_keyhash),
813             M_PFHASH, M_NOWAIT | M_ZERO);
814         V_pf_idhash = mallocarray(pf_hashsize, sizeof(struct pf_idhash),
815             M_PFHASH, M_NOWAIT | M_ZERO);
816         if (V_pf_keyhash == NULL || V_pf_idhash == NULL) {
817                 printf("pf: Unable to allocate memory for "
818                     "state_hashsize %lu.\n", pf_hashsize);
819
820                 free(V_pf_keyhash, M_PFHASH);
821                 free(V_pf_idhash, M_PFHASH);
822
823                 pf_hashsize = PF_HASHSIZ;
824                 V_pf_keyhash = mallocarray(pf_hashsize,
825                     sizeof(struct pf_keyhash), M_PFHASH, M_WAITOK | M_ZERO);
826                 V_pf_idhash = mallocarray(pf_hashsize,
827                     sizeof(struct pf_idhash), M_PFHASH, M_WAITOK | M_ZERO);
828         }
829
830         pf_hashmask = pf_hashsize - 1;
831         for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
832             i++, kh++, ih++) {
833                 mtx_init(&kh->lock, "pf_keyhash", NULL, MTX_DEF | MTX_DUPOK);
834                 mtx_init(&ih->lock, "pf_idhash", NULL, MTX_DEF);
835         }
836
837         /* Source nodes. */
838         V_pf_sources_z = uma_zcreate("pf source nodes",
839             sizeof(struct pf_src_node), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,
840             0);
841         V_pf_limits[PF_LIMIT_SRC_NODES].zone = V_pf_sources_z;
842         uma_zone_set_max(V_pf_sources_z, PFSNODE_HIWAT);
843         uma_zone_set_warning(V_pf_sources_z, "PF source nodes limit reached");
844
845         V_pf_srchash = mallocarray(pf_srchashsize,
846             sizeof(struct pf_srchash), M_PFHASH, M_NOWAIT | M_ZERO);
847         if (V_pf_srchash == NULL) {
848                 printf("pf: Unable to allocate memory for "
849                     "source_hashsize %lu.\n", pf_srchashsize);
850
851                 pf_srchashsize = PF_SRCHASHSIZ;
852                 V_pf_srchash = mallocarray(pf_srchashsize,
853                     sizeof(struct pf_srchash), M_PFHASH, M_WAITOK | M_ZERO);
854         }
855
856         pf_srchashmask = pf_srchashsize - 1;
857         for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++)
858                 mtx_init(&sh->lock, "pf_srchash", NULL, MTX_DEF);
859
860         /* ALTQ */
861         TAILQ_INIT(&V_pf_altqs[0]);
862         TAILQ_INIT(&V_pf_altqs[1]);
863         TAILQ_INIT(&V_pf_pabuf);
864         V_pf_altqs_active = &V_pf_altqs[0];
865         V_pf_altqs_inactive = &V_pf_altqs[1];
866
867         /* Send & overload+flush queues. */
868         STAILQ_INIT(&V_pf_sendqueue);
869         SLIST_INIT(&V_pf_overloadqueue);
870         TASK_INIT(&V_pf_overloadtask, 0, pf_overload_task, curvnet);
871
872         /* Unlinked, but may be referenced rules. */
873         TAILQ_INIT(&V_pf_unlinked_rules);
874 }
875
876 void
877 pf_mtag_cleanup()
878 {
879
880         uma_zdestroy(pf_mtag_z);
881 }
882
883 void
884 pf_cleanup()
885 {
886         struct pf_keyhash       *kh;
887         struct pf_idhash        *ih;
888         struct pf_srchash       *sh;
889         struct pf_send_entry    *pfse, *next;
890         u_int i;
891
892         for (i = 0, kh = V_pf_keyhash, ih = V_pf_idhash; i <= pf_hashmask;
893             i++, kh++, ih++) {
894                 KASSERT(LIST_EMPTY(&kh->keys), ("%s: key hash not empty",
895                     __func__));
896                 KASSERT(LIST_EMPTY(&ih->states), ("%s: id hash not empty",
897                     __func__));
898                 mtx_destroy(&kh->lock);
899                 mtx_destroy(&ih->lock);
900         }
901         free(V_pf_keyhash, M_PFHASH);
902         free(V_pf_idhash, M_PFHASH);
903
904         for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
905                 KASSERT(LIST_EMPTY(&sh->nodes),
906                     ("%s: source node hash not empty", __func__));
907                 mtx_destroy(&sh->lock);
908         }
909         free(V_pf_srchash, M_PFHASH);
910
911         STAILQ_FOREACH_SAFE(pfse, &V_pf_sendqueue, pfse_next, next) {
912                 m_freem(pfse->pfse_m);
913                 free(pfse, M_PFTEMP);
914         }
915
916         uma_zdestroy(V_pf_sources_z);
917         uma_zdestroy(V_pf_state_z);
918         uma_zdestroy(V_pf_state_key_z);
919 }
920
921 static int
922 pf_mtag_uminit(void *mem, int size, int how)
923 {
924         struct m_tag *t;
925
926         t = (struct m_tag *)mem;
927         t->m_tag_cookie = MTAG_ABI_COMPAT;
928         t->m_tag_id = PACKET_TAG_PF;
929         t->m_tag_len = sizeof(struct pf_mtag);
930         t->m_tag_free = pf_mtag_free;
931
932         return (0);
933 }
934
935 static void
936 pf_mtag_free(struct m_tag *t)
937 {
938
939         uma_zfree(pf_mtag_z, t);
940 }
941
942 struct pf_mtag *
943 pf_get_mtag(struct mbuf *m)
944 {
945         struct m_tag *mtag;
946
947         if ((mtag = m_tag_find(m, PACKET_TAG_PF, NULL)) != NULL)
948                 return ((struct pf_mtag *)(mtag + 1));
949
950         mtag = uma_zalloc(pf_mtag_z, M_NOWAIT);
951         if (mtag == NULL)
952                 return (NULL);
953         bzero(mtag + 1, sizeof(struct pf_mtag));
954         m_tag_prepend(m, mtag);
955
956         return ((struct pf_mtag *)(mtag + 1));
957 }
958
959 static int
960 pf_state_key_attach(struct pf_state_key *skw, struct pf_state_key *sks,
961     struct pf_state *s)
962 {
963         struct pf_keyhash       *khs, *khw, *kh;
964         struct pf_state_key     *sk, *cur;
965         struct pf_state         *si, *olds = NULL;
966         int idx;
967
968         KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
969         KASSERT(s->key[PF_SK_WIRE] == NULL, ("%s: state has key", __func__));
970         KASSERT(s->key[PF_SK_STACK] == NULL, ("%s: state has key", __func__));
971
972         /*
973          * We need to lock hash slots of both keys. To avoid deadlock
974          * we always lock the slot with lower address first. Unlock order
975          * isn't important.
976          *
977          * We also need to lock ID hash slot before dropping key
978          * locks. On success we return with ID hash slot locked.
979          */
980
981         if (skw == sks) {
982                 khs = khw = &V_pf_keyhash[pf_hashkey(skw)];
983                 PF_HASHROW_LOCK(khs);
984         } else {
985                 khs = &V_pf_keyhash[pf_hashkey(sks)];
986                 khw = &V_pf_keyhash[pf_hashkey(skw)];
987                 if (khs == khw) {
988                         PF_HASHROW_LOCK(khs);
989                 } else if (khs < khw) {
990                         PF_HASHROW_LOCK(khs);
991                         PF_HASHROW_LOCK(khw);
992                 } else {
993                         PF_HASHROW_LOCK(khw);
994                         PF_HASHROW_LOCK(khs);
995                 }
996         }
997
998 #define KEYS_UNLOCK()   do {                    \
999         if (khs != khw) {                       \
1000                 PF_HASHROW_UNLOCK(khs);         \
1001                 PF_HASHROW_UNLOCK(khw);         \
1002         } else                                  \
1003                 PF_HASHROW_UNLOCK(khs);         \
1004 } while (0)
1005
1006         /*
1007          * First run: start with wire key.
1008          */
1009         sk = skw;
1010         kh = khw;
1011         idx = PF_SK_WIRE;
1012
1013 keyattach:
1014         LIST_FOREACH(cur, &kh->keys, entry)
1015                 if (bcmp(cur, sk, sizeof(struct pf_state_key_cmp)) == 0)
1016                         break;
1017
1018         if (cur != NULL) {
1019                 /* Key exists. Check for same kif, if none, add to key. */
1020                 TAILQ_FOREACH(si, &cur->states[idx], key_list[idx]) {
1021                         struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(si)];
1022
1023                         PF_HASHROW_LOCK(ih);
1024                         if (si->kif == s->kif &&
1025                             si->direction == s->direction) {
1026                                 if (sk->proto == IPPROTO_TCP &&
1027                                     si->src.state >= TCPS_FIN_WAIT_2 &&
1028                                     si->dst.state >= TCPS_FIN_WAIT_2) {
1029                                         /*
1030                                          * New state matches an old >FIN_WAIT_2
1031                                          * state. We can't drop key hash locks,
1032                                          * thus we can't unlink it properly.
1033                                          *
1034                                          * As a workaround we drop it into
1035                                          * TCPS_CLOSED state, schedule purge
1036                                          * ASAP and push it into the very end
1037                                          * of the slot TAILQ, so that it won't
1038                                          * conflict with our new state.
1039                                          */
1040                                         si->src.state = si->dst.state =
1041                                             TCPS_CLOSED;
1042                                         si->timeout = PFTM_PURGE;
1043                                         olds = si;
1044                                 } else {
1045                                         if (V_pf_status.debug >= PF_DEBUG_MISC) {
1046                                                 printf("pf: %s key attach "
1047                                                     "failed on %s: ",
1048                                                     (idx == PF_SK_WIRE) ?
1049                                                     "wire" : "stack",
1050                                                     s->kif->pfik_name);
1051                                                 pf_print_state_parts(s,
1052                                                     (idx == PF_SK_WIRE) ?
1053                                                     sk : NULL,
1054                                                     (idx == PF_SK_STACK) ?
1055                                                     sk : NULL);
1056                                                 printf(", existing: ");
1057                                                 pf_print_state_parts(si,
1058                                                     (idx == PF_SK_WIRE) ?
1059                                                     sk : NULL,
1060                                                     (idx == PF_SK_STACK) ?
1061                                                     sk : NULL);
1062                                                 printf("\n");
1063                                         }
1064                                         PF_HASHROW_UNLOCK(ih);
1065                                         KEYS_UNLOCK();
1066                                         uma_zfree(V_pf_state_key_z, sk);
1067                                         if (idx == PF_SK_STACK)
1068                                                 pf_detach_state(s);
1069                                         return (EEXIST); /* collision! */
1070                                 }
1071                         }
1072                         PF_HASHROW_UNLOCK(ih);
1073                 }
1074                 uma_zfree(V_pf_state_key_z, sk);
1075                 s->key[idx] = cur;
1076         } else {
1077                 LIST_INSERT_HEAD(&kh->keys, sk, entry);
1078                 s->key[idx] = sk;
1079         }
1080
1081 stateattach:
1082         /* List is sorted, if-bound states before floating. */
1083         if (s->kif == V_pfi_all)
1084                 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], s, key_list[idx]);
1085         else
1086                 TAILQ_INSERT_HEAD(&s->key[idx]->states[idx], s, key_list[idx]);
1087
1088         if (olds) {
1089                 TAILQ_REMOVE(&s->key[idx]->states[idx], olds, key_list[idx]);
1090                 TAILQ_INSERT_TAIL(&s->key[idx]->states[idx], olds,
1091                     key_list[idx]);
1092                 olds = NULL;
1093         }
1094
1095         /*
1096          * Attach done. See how should we (or should not?)
1097          * attach a second key.
1098          */
1099         if (sks == skw) {
1100                 s->key[PF_SK_STACK] = s->key[PF_SK_WIRE];
1101                 idx = PF_SK_STACK;
1102                 sks = NULL;
1103                 goto stateattach;
1104         } else if (sks != NULL) {
1105                 /*
1106                  * Continue attaching with stack key.
1107                  */
1108                 sk = sks;
1109                 kh = khs;
1110                 idx = PF_SK_STACK;
1111                 sks = NULL;
1112                 goto keyattach;
1113         }
1114
1115         PF_STATE_LOCK(s);
1116         KEYS_UNLOCK();
1117
1118         KASSERT(s->key[PF_SK_WIRE] != NULL && s->key[PF_SK_STACK] != NULL,
1119             ("%s failure", __func__));
1120
1121         return (0);
1122 #undef  KEYS_UNLOCK
1123 }
1124
1125 static void
1126 pf_detach_state(struct pf_state *s)
1127 {
1128         struct pf_state_key *sks = s->key[PF_SK_STACK];
1129         struct pf_keyhash *kh;
1130
1131         if (sks != NULL) {
1132                 kh = &V_pf_keyhash[pf_hashkey(sks)];
1133                 PF_HASHROW_LOCK(kh);
1134                 if (s->key[PF_SK_STACK] != NULL)
1135                         pf_state_key_detach(s, PF_SK_STACK);
1136                 /*
1137                  * If both point to same key, then we are done.
1138                  */
1139                 if (sks == s->key[PF_SK_WIRE]) {
1140                         pf_state_key_detach(s, PF_SK_WIRE);
1141                         PF_HASHROW_UNLOCK(kh);
1142                         return;
1143                 }
1144                 PF_HASHROW_UNLOCK(kh);
1145         }
1146
1147         if (s->key[PF_SK_WIRE] != NULL) {
1148                 kh = &V_pf_keyhash[pf_hashkey(s->key[PF_SK_WIRE])];
1149                 PF_HASHROW_LOCK(kh);
1150                 if (s->key[PF_SK_WIRE] != NULL)
1151                         pf_state_key_detach(s, PF_SK_WIRE);
1152                 PF_HASHROW_UNLOCK(kh);
1153         }
1154 }
1155
1156 static void
1157 pf_state_key_detach(struct pf_state *s, int idx)
1158 {
1159         struct pf_state_key *sk = s->key[idx];
1160 #ifdef INVARIANTS
1161         struct pf_keyhash *kh = &V_pf_keyhash[pf_hashkey(sk)];
1162
1163         PF_HASHROW_ASSERT(kh);
1164 #endif
1165         TAILQ_REMOVE(&sk->states[idx], s, key_list[idx]);
1166         s->key[idx] = NULL;
1167
1168         if (TAILQ_EMPTY(&sk->states[0]) && TAILQ_EMPTY(&sk->states[1])) {
1169                 LIST_REMOVE(sk, entry);
1170                 uma_zfree(V_pf_state_key_z, sk);
1171         }
1172 }
1173
1174 static int
1175 pf_state_key_ctor(void *mem, int size, void *arg, int flags)
1176 {
1177         struct pf_state_key *sk = mem;
1178
1179         bzero(sk, sizeof(struct pf_state_key_cmp));
1180         TAILQ_INIT(&sk->states[PF_SK_WIRE]);
1181         TAILQ_INIT(&sk->states[PF_SK_STACK]);
1182
1183         return (0);
1184 }
1185
1186 struct pf_state_key *
1187 pf_state_key_setup(struct pf_pdesc *pd, struct pf_addr *saddr,
1188         struct pf_addr *daddr, u_int16_t sport, u_int16_t dport)
1189 {
1190         struct pf_state_key *sk;
1191
1192         sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1193         if (sk == NULL)
1194                 return (NULL);
1195
1196         PF_ACPY(&sk->addr[pd->sidx], saddr, pd->af);
1197         PF_ACPY(&sk->addr[pd->didx], daddr, pd->af);
1198         sk->port[pd->sidx] = sport;
1199         sk->port[pd->didx] = dport;
1200         sk->proto = pd->proto;
1201         sk->af = pd->af;
1202
1203         return (sk);
1204 }
1205
1206 struct pf_state_key *
1207 pf_state_key_clone(struct pf_state_key *orig)
1208 {
1209         struct pf_state_key *sk;
1210
1211         sk = uma_zalloc(V_pf_state_key_z, M_NOWAIT);
1212         if (sk == NULL)
1213                 return (NULL);
1214
1215         bcopy(orig, sk, sizeof(struct pf_state_key_cmp));
1216
1217         return (sk);
1218 }
1219
1220 int
1221 pf_state_insert(struct pfi_kif *kif, struct pf_state_key *skw,
1222     struct pf_state_key *sks, struct pf_state *s)
1223 {
1224         struct pf_idhash *ih;
1225         struct pf_state *cur;
1226         int error;
1227
1228         KASSERT(TAILQ_EMPTY(&sks->states[0]) && TAILQ_EMPTY(&sks->states[1]),
1229             ("%s: sks not pristine", __func__));
1230         KASSERT(TAILQ_EMPTY(&skw->states[0]) && TAILQ_EMPTY(&skw->states[1]),
1231             ("%s: skw not pristine", __func__));
1232         KASSERT(s->refs == 0, ("%s: state not pristine", __func__));
1233
1234         s->kif = kif;
1235
1236         if (s->id == 0 && s->creatorid == 0) {
1237                 /* XXX: should be atomic, but probability of collision low */
1238                 if ((s->id = V_pf_stateid[curcpu]++) == PFID_MAXID)
1239                         V_pf_stateid[curcpu] = 1;
1240                 s->id |= (uint64_t )curcpu << PFID_CPUSHIFT;
1241                 s->id = htobe64(s->id);
1242                 s->creatorid = V_pf_status.hostid;
1243         }
1244
1245         /* Returns with ID locked on success. */
1246         if ((error = pf_state_key_attach(skw, sks, s)) != 0)
1247                 return (error);
1248
1249         ih = &V_pf_idhash[PF_IDHASH(s)];
1250         PF_HASHROW_ASSERT(ih);
1251         LIST_FOREACH(cur, &ih->states, entry)
1252                 if (cur->id == s->id && cur->creatorid == s->creatorid)
1253                         break;
1254
1255         if (cur != NULL) {
1256                 PF_HASHROW_UNLOCK(ih);
1257                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
1258                         printf("pf: state ID collision: "
1259                             "id: %016llx creatorid: %08x\n",
1260                             (unsigned long long)be64toh(s->id),
1261                             ntohl(s->creatorid));
1262                 }
1263                 pf_detach_state(s);
1264                 return (EEXIST);
1265         }
1266         LIST_INSERT_HEAD(&ih->states, s, entry);
1267         /* One for keys, one for ID hash. */
1268         refcount_init(&s->refs, 2);
1269
1270         counter_u64_add(V_pf_status.fcounters[FCNT_STATE_INSERT], 1);
1271         if (pfsync_insert_state_ptr != NULL)
1272                 pfsync_insert_state_ptr(s);
1273
1274         /* Returns locked. */
1275         return (0);
1276 }
1277
1278 /*
1279  * Find state by ID: returns with locked row on success.
1280  */
1281 struct pf_state *
1282 pf_find_state_byid(uint64_t id, uint32_t creatorid)
1283 {
1284         struct pf_idhash *ih;
1285         struct pf_state *s;
1286
1287         counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1288
1289         ih = &V_pf_idhash[(be64toh(id) % (pf_hashmask + 1))];
1290
1291         PF_HASHROW_LOCK(ih);
1292         LIST_FOREACH(s, &ih->states, entry)
1293                 if (s->id == id && s->creatorid == creatorid)
1294                         break;
1295
1296         if (s == NULL)
1297                 PF_HASHROW_UNLOCK(ih);
1298
1299         return (s);
1300 }
1301
1302 /*
1303  * Find state by key.
1304  * Returns with ID hash slot locked on success.
1305  */
1306 static struct pf_state *
1307 pf_find_state(struct pfi_kif *kif, struct pf_state_key_cmp *key, u_int dir)
1308 {
1309         struct pf_keyhash       *kh;
1310         struct pf_state_key     *sk;
1311         struct pf_state         *s;
1312         int idx;
1313
1314         counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1315
1316         kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1317
1318         PF_HASHROW_LOCK(kh);
1319         LIST_FOREACH(sk, &kh->keys, entry)
1320                 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1321                         break;
1322         if (sk == NULL) {
1323                 PF_HASHROW_UNLOCK(kh);
1324                 return (NULL);
1325         }
1326
1327         idx = (dir == PF_IN ? PF_SK_WIRE : PF_SK_STACK);
1328
1329         /* List is sorted, if-bound states before floating ones. */
1330         TAILQ_FOREACH(s, &sk->states[idx], key_list[idx])
1331                 if (s->kif == V_pfi_all || s->kif == kif) {
1332                         PF_STATE_LOCK(s);
1333                         PF_HASHROW_UNLOCK(kh);
1334                         if (s->timeout >= PFTM_MAX) {
1335                                 /*
1336                                  * State is either being processed by
1337                                  * pf_unlink_state() in an other thread, or
1338                                  * is scheduled for immediate expiry.
1339                                  */
1340                                 PF_STATE_UNLOCK(s);
1341                                 return (NULL);
1342                         }
1343                         return (s);
1344                 }
1345         PF_HASHROW_UNLOCK(kh);
1346
1347         return (NULL);
1348 }
1349
1350 struct pf_state *
1351 pf_find_state_all(struct pf_state_key_cmp *key, u_int dir, int *more)
1352 {
1353         struct pf_keyhash       *kh;
1354         struct pf_state_key     *sk;
1355         struct pf_state         *s, *ret = NULL;
1356         int                      idx, inout = 0;
1357
1358         counter_u64_add(V_pf_status.fcounters[FCNT_STATE_SEARCH], 1);
1359
1360         kh = &V_pf_keyhash[pf_hashkey((struct pf_state_key *)key)];
1361
1362         PF_HASHROW_LOCK(kh);
1363         LIST_FOREACH(sk, &kh->keys, entry)
1364                 if (bcmp(sk, key, sizeof(struct pf_state_key_cmp)) == 0)
1365                         break;
1366         if (sk == NULL) {
1367                 PF_HASHROW_UNLOCK(kh);
1368                 return (NULL);
1369         }
1370         switch (dir) {
1371         case PF_IN:
1372                 idx = PF_SK_WIRE;
1373                 break;
1374         case PF_OUT:
1375                 idx = PF_SK_STACK;
1376                 break;
1377         case PF_INOUT:
1378                 idx = PF_SK_WIRE;
1379                 inout = 1;
1380                 break;
1381         default:
1382                 panic("%s: dir %u", __func__, dir);
1383         }
1384 second_run:
1385         TAILQ_FOREACH(s, &sk->states[idx], key_list[idx]) {
1386                 if (more == NULL) {
1387                         PF_HASHROW_UNLOCK(kh);
1388                         return (s);
1389                 }
1390
1391                 if (ret)
1392                         (*more)++;
1393                 else
1394                         ret = s;
1395         }
1396         if (inout == 1) {
1397                 inout = 0;
1398                 idx = PF_SK_STACK;
1399                 goto second_run;
1400         }
1401         PF_HASHROW_UNLOCK(kh);
1402
1403         return (ret);
1404 }
1405
1406 /* END state table stuff */
1407
1408 static void
1409 pf_send(struct pf_send_entry *pfse)
1410 {
1411
1412         PF_SENDQ_LOCK();
1413         STAILQ_INSERT_TAIL(&V_pf_sendqueue, pfse, pfse_next);
1414         PF_SENDQ_UNLOCK();
1415         swi_sched(V_pf_swi_cookie, 0);
1416 }
1417
1418 void
1419 pf_intr(void *v)
1420 {
1421         struct pf_send_head queue;
1422         struct pf_send_entry *pfse, *next;
1423
1424         CURVNET_SET((struct vnet *)v);
1425
1426         PF_SENDQ_LOCK();
1427         queue = V_pf_sendqueue;
1428         STAILQ_INIT(&V_pf_sendqueue);
1429         PF_SENDQ_UNLOCK();
1430
1431         STAILQ_FOREACH_SAFE(pfse, &queue, pfse_next, next) {
1432                 switch (pfse->pfse_type) {
1433 #ifdef INET
1434                 case PFSE_IP:
1435                         ip_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL);
1436                         break;
1437                 case PFSE_ICMP:
1438                         icmp_error(pfse->pfse_m, pfse->icmpopts.type,
1439                             pfse->icmpopts.code, 0, pfse->icmpopts.mtu);
1440                         break;
1441 #endif /* INET */
1442 #ifdef INET6
1443                 case PFSE_IP6:
1444                         ip6_output(pfse->pfse_m, NULL, NULL, 0, NULL, NULL,
1445                             NULL);
1446                         break;
1447                 case PFSE_ICMP6:
1448                         icmp6_error(pfse->pfse_m, pfse->icmpopts.type,
1449                             pfse->icmpopts.code, pfse->icmpopts.mtu);
1450                         break;
1451 #endif /* INET6 */
1452                 default:
1453                         panic("%s: unknown type", __func__);
1454                 }
1455                 free(pfse, M_PFTEMP);
1456         }
1457         CURVNET_RESTORE();
1458 }
1459
1460 void
1461 pf_purge_thread(void *unused __unused)
1462 {
1463         VNET_ITERATOR_DECL(vnet_iter);
1464
1465         sx_xlock(&pf_end_lock);
1466         while (pf_end_threads == 0) {
1467                 sx_sleep(pf_purge_thread, &pf_end_lock, 0, "pftm", hz / 10);
1468
1469                 VNET_LIST_RLOCK();
1470                 VNET_FOREACH(vnet_iter) {
1471                         CURVNET_SET(vnet_iter);
1472
1473
1474                         /* Wait until V_pf_default_rule is initialized. */
1475                         if (V_pf_vnet_active == 0) {
1476                                 CURVNET_RESTORE();
1477                                 continue;
1478                         }
1479
1480                         /*
1481                          *  Process 1/interval fraction of the state
1482                          * table every run.
1483                          */
1484                         V_pf_purge_idx =
1485                             pf_purge_expired_states(V_pf_purge_idx, pf_hashmask /
1486                             (V_pf_default_rule.timeout[PFTM_INTERVAL] * 10));
1487
1488                         /*
1489                          * Purge other expired types every
1490                          * PFTM_INTERVAL seconds.
1491                          */
1492                         if (V_pf_purge_idx == 0) {
1493                                 /*
1494                                  * Order is important:
1495                                  * - states and src nodes reference rules
1496                                  * - states and rules reference kifs
1497                                  */
1498                                 pf_purge_expired_fragments();
1499                                 pf_purge_expired_src_nodes();
1500                                 pf_purge_unlinked_rules();
1501                                 pfi_kif_purge();
1502                         }
1503                         CURVNET_RESTORE();
1504                 }
1505                 VNET_LIST_RUNLOCK();
1506         }
1507
1508         pf_end_threads++;
1509         sx_xunlock(&pf_end_lock);
1510         kproc_exit(0);
1511 }
1512
1513 void
1514 pf_unload_vnet_purge(void)
1515 {
1516
1517         /*
1518          * To cleanse up all kifs and rules we need
1519          * two runs: first one clears reference flags,
1520          * then pf_purge_expired_states() doesn't
1521          * raise them, and then second run frees.
1522          */
1523         pf_purge_unlinked_rules();
1524         pfi_kif_purge();
1525
1526         /*
1527          * Now purge everything.
1528          */
1529         pf_purge_expired_states(0, pf_hashmask);
1530         pf_purge_fragments(UINT_MAX);
1531         pf_purge_expired_src_nodes();
1532
1533         /*
1534          * Now all kifs & rules should be unreferenced,
1535          * thus should be successfully freed.
1536          */
1537         pf_purge_unlinked_rules();
1538         pfi_kif_purge();
1539 }
1540
1541
1542 u_int32_t
1543 pf_state_expires(const struct pf_state *state)
1544 {
1545         u_int32_t       timeout;
1546         u_int32_t       start;
1547         u_int32_t       end;
1548         u_int32_t       states;
1549
1550         /* handle all PFTM_* > PFTM_MAX here */
1551         if (state->timeout == PFTM_PURGE)
1552                 return (time_uptime);
1553         KASSERT(state->timeout != PFTM_UNLINKED,
1554             ("pf_state_expires: timeout == PFTM_UNLINKED"));
1555         KASSERT((state->timeout < PFTM_MAX),
1556             ("pf_state_expires: timeout > PFTM_MAX"));
1557         timeout = state->rule.ptr->timeout[state->timeout];
1558         if (!timeout)
1559                 timeout = V_pf_default_rule.timeout[state->timeout];
1560         start = state->rule.ptr->timeout[PFTM_ADAPTIVE_START];
1561         if (start) {
1562                 end = state->rule.ptr->timeout[PFTM_ADAPTIVE_END];
1563                 states = counter_u64_fetch(state->rule.ptr->states_cur);
1564         } else {
1565                 start = V_pf_default_rule.timeout[PFTM_ADAPTIVE_START];
1566                 end = V_pf_default_rule.timeout[PFTM_ADAPTIVE_END];
1567                 states = V_pf_status.states;
1568         }
1569         if (end && states > start && start < end) {
1570                 if (states < end)
1571                         return (state->expire + timeout * (end - states) /
1572                             (end - start));
1573                 else
1574                         return (time_uptime);
1575         }
1576         return (state->expire + timeout);
1577 }
1578
1579 void
1580 pf_purge_expired_src_nodes()
1581 {
1582         struct pf_src_node_list  freelist;
1583         struct pf_srchash       *sh;
1584         struct pf_src_node      *cur, *next;
1585         int i;
1586
1587         LIST_INIT(&freelist);
1588         for (i = 0, sh = V_pf_srchash; i <= pf_srchashmask; i++, sh++) {
1589             PF_HASHROW_LOCK(sh);
1590             LIST_FOREACH_SAFE(cur, &sh->nodes, entry, next)
1591                 if (cur->states == 0 && cur->expire <= time_uptime) {
1592                         pf_unlink_src_node(cur);
1593                         LIST_INSERT_HEAD(&freelist, cur, entry);
1594                 } else if (cur->rule.ptr != NULL)
1595                         cur->rule.ptr->rule_flag |= PFRULE_REFS;
1596             PF_HASHROW_UNLOCK(sh);
1597         }
1598
1599         pf_free_src_nodes(&freelist);
1600
1601         V_pf_status.src_nodes = uma_zone_get_cur(V_pf_sources_z);
1602 }
1603
1604 static void
1605 pf_src_tree_remove_state(struct pf_state *s)
1606 {
1607         struct pf_src_node *sn;
1608         struct pf_srchash *sh;
1609         uint32_t timeout;
1610
1611         timeout = s->rule.ptr->timeout[PFTM_SRC_NODE] ?
1612             s->rule.ptr->timeout[PFTM_SRC_NODE] :
1613             V_pf_default_rule.timeout[PFTM_SRC_NODE];
1614
1615         if (s->src_node != NULL) {
1616                 sn = s->src_node;
1617                 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1618                 PF_HASHROW_LOCK(sh);
1619                 if (s->src.tcp_est)
1620                         --sn->conn;
1621                 if (--sn->states == 0)
1622                         sn->expire = time_uptime + timeout;
1623                 PF_HASHROW_UNLOCK(sh);
1624         }
1625         if (s->nat_src_node != s->src_node && s->nat_src_node != NULL) {
1626                 sn = s->nat_src_node;
1627                 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
1628                 PF_HASHROW_LOCK(sh);
1629                 if (--sn->states == 0)
1630                         sn->expire = time_uptime + timeout;
1631                 PF_HASHROW_UNLOCK(sh);
1632         }
1633         s->src_node = s->nat_src_node = NULL;
1634 }
1635
1636 /*
1637  * Unlink and potentilly free a state. Function may be
1638  * called with ID hash row locked, but always returns
1639  * unlocked, since it needs to go through key hash locking.
1640  */
1641 int
1642 pf_unlink_state(struct pf_state *s, u_int flags)
1643 {
1644         struct pf_idhash *ih = &V_pf_idhash[PF_IDHASH(s)];
1645
1646         if ((flags & PF_ENTER_LOCKED) == 0)
1647                 PF_HASHROW_LOCK(ih);
1648         else
1649                 PF_HASHROW_ASSERT(ih);
1650
1651         if (s->timeout == PFTM_UNLINKED) {
1652                 /*
1653                  * State is being processed
1654                  * by pf_unlink_state() in
1655                  * an other thread.
1656                  */
1657                 PF_HASHROW_UNLOCK(ih);
1658                 return (0);     /* XXXGL: undefined actually */
1659         }
1660
1661         if (s->src.state == PF_TCPS_PROXY_DST) {
1662                 /* XXX wire key the right one? */
1663                 pf_send_tcp(NULL, s->rule.ptr, s->key[PF_SK_WIRE]->af,
1664                     &s->key[PF_SK_WIRE]->addr[1],
1665                     &s->key[PF_SK_WIRE]->addr[0],
1666                     s->key[PF_SK_WIRE]->port[1],
1667                     s->key[PF_SK_WIRE]->port[0],
1668                     s->src.seqhi, s->src.seqlo + 1,
1669                     TH_RST|TH_ACK, 0, 0, 0, 1, s->tag, NULL);
1670         }
1671
1672         LIST_REMOVE(s, entry);
1673         pf_src_tree_remove_state(s);
1674
1675         if (pfsync_delete_state_ptr != NULL)
1676                 pfsync_delete_state_ptr(s);
1677
1678         STATE_DEC_COUNTERS(s);
1679
1680         s->timeout = PFTM_UNLINKED;
1681
1682         PF_HASHROW_UNLOCK(ih);
1683
1684         pf_detach_state(s);
1685         /* pf_state_insert() initialises refs to 2, so we can never release the
1686          * last reference here, only in pf_release_state(). */
1687         (void)refcount_release(&s->refs);
1688
1689         return (pf_release_state(s));
1690 }
1691
1692 void
1693 pf_free_state(struct pf_state *cur)
1694 {
1695
1696         KASSERT(cur->refs == 0, ("%s: %p has refs", __func__, cur));
1697         KASSERT(cur->timeout == PFTM_UNLINKED, ("%s: timeout %u", __func__,
1698             cur->timeout));
1699
1700         pf_normalize_tcp_cleanup(cur);
1701         uma_zfree(V_pf_state_z, cur);
1702         counter_u64_add(V_pf_status.fcounters[FCNT_STATE_REMOVALS], 1);
1703 }
1704
1705 /*
1706  * Called only from pf_purge_thread(), thus serialized.
1707  */
1708 static u_int
1709 pf_purge_expired_states(u_int i, int maxcheck)
1710 {
1711         struct pf_idhash *ih;
1712         struct pf_state *s;
1713
1714         V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1715
1716         /*
1717          * Go through hash and unlink states that expire now.
1718          */
1719         while (maxcheck > 0) {
1720
1721                 ih = &V_pf_idhash[i];
1722 relock:
1723                 PF_HASHROW_LOCK(ih);
1724                 LIST_FOREACH(s, &ih->states, entry) {
1725                         if (pf_state_expires(s) <= time_uptime) {
1726                                 V_pf_status.states -=
1727                                     pf_unlink_state(s, PF_ENTER_LOCKED);
1728                                 goto relock;
1729                         }
1730                         s->rule.ptr->rule_flag |= PFRULE_REFS;
1731                         if (s->nat_rule.ptr != NULL)
1732                                 s->nat_rule.ptr->rule_flag |= PFRULE_REFS;
1733                         if (s->anchor.ptr != NULL)
1734                                 s->anchor.ptr->rule_flag |= PFRULE_REFS;
1735                         s->kif->pfik_flags |= PFI_IFLAG_REFS;
1736                         if (s->rt_kif)
1737                                 s->rt_kif->pfik_flags |= PFI_IFLAG_REFS;
1738                 }
1739                 PF_HASHROW_UNLOCK(ih);
1740
1741                 /* Return when we hit end of hash. */
1742                 if (++i > pf_hashmask) {
1743                         V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1744                         return (0);
1745                 }
1746
1747                 maxcheck--;
1748         }
1749
1750         V_pf_status.states = uma_zone_get_cur(V_pf_state_z);
1751
1752         return (i);
1753 }
1754
1755 static void
1756 pf_purge_unlinked_rules()
1757 {
1758         struct pf_rulequeue tmpq;
1759         struct pf_rule *r, *r1;
1760
1761         /*
1762          * If we have overloading task pending, then we'd
1763          * better skip purging this time. There is a tiny
1764          * probability that overloading task references
1765          * an already unlinked rule.
1766          */
1767         PF_OVERLOADQ_LOCK();
1768         if (!SLIST_EMPTY(&V_pf_overloadqueue)) {
1769                 PF_OVERLOADQ_UNLOCK();
1770                 return;
1771         }
1772         PF_OVERLOADQ_UNLOCK();
1773
1774         /*
1775          * Do naive mark-and-sweep garbage collecting of old rules.
1776          * Reference flag is raised by pf_purge_expired_states()
1777          * and pf_purge_expired_src_nodes().
1778          *
1779          * To avoid LOR between PF_UNLNKDRULES_LOCK/PF_RULES_WLOCK,
1780          * use a temporary queue.
1781          */
1782         TAILQ_INIT(&tmpq);
1783         PF_UNLNKDRULES_LOCK();
1784         TAILQ_FOREACH_SAFE(r, &V_pf_unlinked_rules, entries, r1) {
1785                 if (!(r->rule_flag & PFRULE_REFS)) {
1786                         TAILQ_REMOVE(&V_pf_unlinked_rules, r, entries);
1787                         TAILQ_INSERT_TAIL(&tmpq, r, entries);
1788                 } else
1789                         r->rule_flag &= ~PFRULE_REFS;
1790         }
1791         PF_UNLNKDRULES_UNLOCK();
1792
1793         if (!TAILQ_EMPTY(&tmpq)) {
1794                 PF_RULES_WLOCK();
1795                 TAILQ_FOREACH_SAFE(r, &tmpq, entries, r1) {
1796                         TAILQ_REMOVE(&tmpq, r, entries);
1797                         pf_free_rule(r);
1798                 }
1799                 PF_RULES_WUNLOCK();
1800         }
1801 }
1802
1803 void
1804 pf_print_host(struct pf_addr *addr, u_int16_t p, sa_family_t af)
1805 {
1806         switch (af) {
1807 #ifdef INET
1808         case AF_INET: {
1809                 u_int32_t a = ntohl(addr->addr32[0]);
1810                 printf("%u.%u.%u.%u", (a>>24)&255, (a>>16)&255,
1811                     (a>>8)&255, a&255);
1812                 if (p) {
1813                         p = ntohs(p);
1814                         printf(":%u", p);
1815                 }
1816                 break;
1817         }
1818 #endif /* INET */
1819 #ifdef INET6
1820         case AF_INET6: {
1821                 u_int16_t b;
1822                 u_int8_t i, curstart, curend, maxstart, maxend;
1823                 curstart = curend = maxstart = maxend = 255;
1824                 for (i = 0; i < 8; i++) {
1825                         if (!addr->addr16[i]) {
1826                                 if (curstart == 255)
1827                                         curstart = i;
1828                                 curend = i;
1829                         } else {
1830                                 if ((curend - curstart) >
1831                                     (maxend - maxstart)) {
1832                                         maxstart = curstart;
1833                                         maxend = curend;
1834                                 }
1835                                 curstart = curend = 255;
1836                         }
1837                 }
1838                 if ((curend - curstart) >
1839                     (maxend - maxstart)) {
1840                         maxstart = curstart;
1841                         maxend = curend;
1842                 }
1843                 for (i = 0; i < 8; i++) {
1844                         if (i >= maxstart && i <= maxend) {
1845                                 if (i == 0)
1846                                         printf(":");
1847                                 if (i == maxend)
1848                                         printf(":");
1849                         } else {
1850                                 b = ntohs(addr->addr16[i]);
1851                                 printf("%x", b);
1852                                 if (i < 7)
1853                                         printf(":");
1854                         }
1855                 }
1856                 if (p) {
1857                         p = ntohs(p);
1858                         printf("[%u]", p);
1859                 }
1860                 break;
1861         }
1862 #endif /* INET6 */
1863         }
1864 }
1865
1866 void
1867 pf_print_state(struct pf_state *s)
1868 {
1869         pf_print_state_parts(s, NULL, NULL);
1870 }
1871
1872 static void
1873 pf_print_state_parts(struct pf_state *s,
1874     struct pf_state_key *skwp, struct pf_state_key *sksp)
1875 {
1876         struct pf_state_key *skw, *sks;
1877         u_int8_t proto, dir;
1878
1879         /* Do our best to fill these, but they're skipped if NULL */
1880         skw = skwp ? skwp : (s ? s->key[PF_SK_WIRE] : NULL);
1881         sks = sksp ? sksp : (s ? s->key[PF_SK_STACK] : NULL);
1882         proto = skw ? skw->proto : (sks ? sks->proto : 0);
1883         dir = s ? s->direction : 0;
1884
1885         switch (proto) {
1886         case IPPROTO_IPV4:
1887                 printf("IPv4");
1888                 break;
1889         case IPPROTO_IPV6:
1890                 printf("IPv6");
1891                 break;
1892         case IPPROTO_TCP:
1893                 printf("TCP");
1894                 break;
1895         case IPPROTO_UDP:
1896                 printf("UDP");
1897                 break;
1898         case IPPROTO_ICMP:
1899                 printf("ICMP");
1900                 break;
1901         case IPPROTO_ICMPV6:
1902                 printf("ICMPv6");
1903                 break;
1904         default:
1905                 printf("%u", proto);
1906                 break;
1907         }
1908         switch (dir) {
1909         case PF_IN:
1910                 printf(" in");
1911                 break;
1912         case PF_OUT:
1913                 printf(" out");
1914                 break;
1915         }
1916         if (skw) {
1917                 printf(" wire: ");
1918                 pf_print_host(&skw->addr[0], skw->port[0], skw->af);
1919                 printf(" ");
1920                 pf_print_host(&skw->addr[1], skw->port[1], skw->af);
1921         }
1922         if (sks) {
1923                 printf(" stack: ");
1924                 if (sks != skw) {
1925                         pf_print_host(&sks->addr[0], sks->port[0], sks->af);
1926                         printf(" ");
1927                         pf_print_host(&sks->addr[1], sks->port[1], sks->af);
1928                 } else
1929                         printf("-");
1930         }
1931         if (s) {
1932                 if (proto == IPPROTO_TCP) {
1933                         printf(" [lo=%u high=%u win=%u modulator=%u",
1934                             s->src.seqlo, s->src.seqhi,
1935                             s->src.max_win, s->src.seqdiff);
1936                         if (s->src.wscale && s->dst.wscale)
1937                                 printf(" wscale=%u",
1938                                     s->src.wscale & PF_WSCALE_MASK);
1939                         printf("]");
1940                         printf(" [lo=%u high=%u win=%u modulator=%u",
1941                             s->dst.seqlo, s->dst.seqhi,
1942                             s->dst.max_win, s->dst.seqdiff);
1943                         if (s->src.wscale && s->dst.wscale)
1944                                 printf(" wscale=%u",
1945                                 s->dst.wscale & PF_WSCALE_MASK);
1946                         printf("]");
1947                 }
1948                 printf(" %u:%u", s->src.state, s->dst.state);
1949         }
1950 }
1951
1952 void
1953 pf_print_flags(u_int8_t f)
1954 {
1955         if (f)
1956                 printf(" ");
1957         if (f & TH_FIN)
1958                 printf("F");
1959         if (f & TH_SYN)
1960                 printf("S");
1961         if (f & TH_RST)
1962                 printf("R");
1963         if (f & TH_PUSH)
1964                 printf("P");
1965         if (f & TH_ACK)
1966                 printf("A");
1967         if (f & TH_URG)
1968                 printf("U");
1969         if (f & TH_ECE)
1970                 printf("E");
1971         if (f & TH_CWR)
1972                 printf("W");
1973 }
1974
1975 #define PF_SET_SKIP_STEPS(i)                                    \
1976         do {                                                    \
1977                 while (head[i] != cur) {                        \
1978                         head[i]->skip[i].ptr = cur;             \
1979                         head[i] = TAILQ_NEXT(head[i], entries); \
1980                 }                                               \
1981         } while (0)
1982
1983 void
1984 pf_calc_skip_steps(struct pf_rulequeue *rules)
1985 {
1986         struct pf_rule *cur, *prev, *head[PF_SKIP_COUNT];
1987         int i;
1988
1989         cur = TAILQ_FIRST(rules);
1990         prev = cur;
1991         for (i = 0; i < PF_SKIP_COUNT; ++i)
1992                 head[i] = cur;
1993         while (cur != NULL) {
1994
1995                 if (cur->kif != prev->kif || cur->ifnot != prev->ifnot)
1996                         PF_SET_SKIP_STEPS(PF_SKIP_IFP);
1997                 if (cur->direction != prev->direction)
1998                         PF_SET_SKIP_STEPS(PF_SKIP_DIR);
1999                 if (cur->af != prev->af)
2000                         PF_SET_SKIP_STEPS(PF_SKIP_AF);
2001                 if (cur->proto != prev->proto)
2002                         PF_SET_SKIP_STEPS(PF_SKIP_PROTO);
2003                 if (cur->src.neg != prev->src.neg ||
2004                     pf_addr_wrap_neq(&cur->src.addr, &prev->src.addr))
2005                         PF_SET_SKIP_STEPS(PF_SKIP_SRC_ADDR);
2006                 if (cur->src.port[0] != prev->src.port[0] ||
2007                     cur->src.port[1] != prev->src.port[1] ||
2008                     cur->src.port_op != prev->src.port_op)
2009                         PF_SET_SKIP_STEPS(PF_SKIP_SRC_PORT);
2010                 if (cur->dst.neg != prev->dst.neg ||
2011                     pf_addr_wrap_neq(&cur->dst.addr, &prev->dst.addr))
2012                         PF_SET_SKIP_STEPS(PF_SKIP_DST_ADDR);
2013                 if (cur->dst.port[0] != prev->dst.port[0] ||
2014                     cur->dst.port[1] != prev->dst.port[1] ||
2015                     cur->dst.port_op != prev->dst.port_op)
2016                         PF_SET_SKIP_STEPS(PF_SKIP_DST_PORT);
2017
2018                 prev = cur;
2019                 cur = TAILQ_NEXT(cur, entries);
2020         }
2021         for (i = 0; i < PF_SKIP_COUNT; ++i)
2022                 PF_SET_SKIP_STEPS(i);
2023 }
2024
2025 static int
2026 pf_addr_wrap_neq(struct pf_addr_wrap *aw1, struct pf_addr_wrap *aw2)
2027 {
2028         if (aw1->type != aw2->type)
2029                 return (1);
2030         switch (aw1->type) {
2031         case PF_ADDR_ADDRMASK:
2032         case PF_ADDR_RANGE:
2033                 if (PF_ANEQ(&aw1->v.a.addr, &aw2->v.a.addr, AF_INET6))
2034                         return (1);
2035                 if (PF_ANEQ(&aw1->v.a.mask, &aw2->v.a.mask, AF_INET6))
2036                         return (1);
2037                 return (0);
2038         case PF_ADDR_DYNIFTL:
2039                 return (aw1->p.dyn->pfid_kt != aw2->p.dyn->pfid_kt);
2040         case PF_ADDR_NOROUTE:
2041         case PF_ADDR_URPFFAILED:
2042                 return (0);
2043         case PF_ADDR_TABLE:
2044                 return (aw1->p.tbl != aw2->p.tbl);
2045         default:
2046                 printf("invalid address type: %d\n", aw1->type);
2047                 return (1);
2048         }
2049 }
2050
2051 /**
2052  * Checksum updates are a little complicated because the checksum in the TCP/UDP
2053  * header isn't always a full checksum. In some cases (i.e. output) it's a
2054  * pseudo-header checksum, which is a partial checksum over src/dst IP
2055  * addresses, protocol number and length.
2056  *
2057  * That means we have the following cases:
2058  *  * Input or forwarding: we don't have TSO, the checksum fields are full
2059  *      checksums, we need to update the checksum whenever we change anything.
2060  *  * Output (i.e. the checksum is a pseudo-header checksum):
2061  *      x The field being updated is src/dst address or affects the length of
2062  *      the packet. We need to update the pseudo-header checksum (note that this
2063  *      checksum is not ones' complement).
2064  *      x Some other field is being modified (e.g. src/dst port numbers): We
2065  *      don't have to update anything.
2066  **/
2067 u_int16_t
2068 pf_cksum_fixup(u_int16_t cksum, u_int16_t old, u_int16_t new, u_int8_t udp)
2069 {
2070         u_int32_t       l;
2071
2072         if (udp && !cksum)
2073                 return (0x0000);
2074         l = cksum + old - new;
2075         l = (l >> 16) + (l & 65535);
2076         l = l & 65535;
2077         if (udp && !l)
2078                 return (0xFFFF);
2079         return (l);
2080 }
2081
2082 u_int16_t
2083 pf_proto_cksum_fixup(struct mbuf *m, u_int16_t cksum, u_int16_t old,
2084         u_int16_t new, u_int8_t udp)
2085 {
2086         if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2087                 return (cksum);
2088
2089         return (pf_cksum_fixup(cksum, old, new, udp));
2090 }
2091
2092 static void
2093 pf_change_ap(struct mbuf *m, struct pf_addr *a, u_int16_t *p, u_int16_t *ic,
2094         u_int16_t *pc, struct pf_addr *an, u_int16_t pn, u_int8_t u,
2095         sa_family_t af)
2096 {
2097         struct pf_addr  ao;
2098         u_int16_t       po = *p;
2099
2100         PF_ACPY(&ao, a, af);
2101         PF_ACPY(a, an, af);
2102
2103         if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | CSUM_DELAY_DATA_IPV6))
2104                 *pc = ~*pc;
2105
2106         *p = pn;
2107
2108         switch (af) {
2109 #ifdef INET
2110         case AF_INET:
2111                 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2112                     ao.addr16[0], an->addr16[0], 0),
2113                     ao.addr16[1], an->addr16[1], 0);
2114                 *p = pn;
2115
2116                 *pc = pf_cksum_fixup(pf_cksum_fixup(*pc,
2117                     ao.addr16[0], an->addr16[0], u),
2118                     ao.addr16[1], an->addr16[1], u);
2119
2120                 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2121                 break;
2122 #endif /* INET */
2123 #ifdef INET6
2124         case AF_INET6:
2125                 *pc = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2126                     pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2127                     pf_cksum_fixup(pf_cksum_fixup(*pc,
2128                     ao.addr16[0], an->addr16[0], u),
2129                     ao.addr16[1], an->addr16[1], u),
2130                     ao.addr16[2], an->addr16[2], u),
2131                     ao.addr16[3], an->addr16[3], u),
2132                     ao.addr16[4], an->addr16[4], u),
2133                     ao.addr16[5], an->addr16[5], u),
2134                     ao.addr16[6], an->addr16[6], u),
2135                     ao.addr16[7], an->addr16[7], u);
2136
2137                 *pc = pf_proto_cksum_fixup(m, *pc, po, pn, u);
2138                 break;
2139 #endif /* INET6 */
2140         }
2141
2142         if (m->m_pkthdr.csum_flags & (CSUM_DELAY_DATA | 
2143             CSUM_DELAY_DATA_IPV6)) {
2144                 *pc = ~*pc;
2145                 if (! *pc)
2146                         *pc = 0xffff;
2147         }
2148 }
2149
2150 /* Changes a u_int32_t.  Uses a void * so there are no align restrictions */
2151 void
2152 pf_change_a(void *a, u_int16_t *c, u_int32_t an, u_int8_t u)
2153 {
2154         u_int32_t       ao;
2155
2156         memcpy(&ao, a, sizeof(ao));
2157         memcpy(a, &an, sizeof(u_int32_t));
2158         *c = pf_cksum_fixup(pf_cksum_fixup(*c, ao / 65536, an / 65536, u),
2159             ao % 65536, an % 65536, u);
2160 }
2161
2162 void
2163 pf_change_proto_a(struct mbuf *m, void *a, u_int16_t *c, u_int32_t an, u_int8_t udp)
2164 {
2165         u_int32_t       ao;
2166
2167         memcpy(&ao, a, sizeof(ao));
2168         memcpy(a, &an, sizeof(u_int32_t));
2169
2170         *c = pf_proto_cksum_fixup(m,
2171             pf_proto_cksum_fixup(m, *c, ao / 65536, an / 65536, udp),
2172             ao % 65536, an % 65536, udp);
2173 }
2174
2175 #ifdef INET6
2176 static void
2177 pf_change_a6(struct pf_addr *a, u_int16_t *c, struct pf_addr *an, u_int8_t u)
2178 {
2179         struct pf_addr  ao;
2180
2181         PF_ACPY(&ao, a, AF_INET6);
2182         PF_ACPY(a, an, AF_INET6);
2183
2184         *c = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2185             pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2186             pf_cksum_fixup(pf_cksum_fixup(*c,
2187             ao.addr16[0], an->addr16[0], u),
2188             ao.addr16[1], an->addr16[1], u),
2189             ao.addr16[2], an->addr16[2], u),
2190             ao.addr16[3], an->addr16[3], u),
2191             ao.addr16[4], an->addr16[4], u),
2192             ao.addr16[5], an->addr16[5], u),
2193             ao.addr16[6], an->addr16[6], u),
2194             ao.addr16[7], an->addr16[7], u);
2195 }
2196 #endif /* INET6 */
2197
2198 static void
2199 pf_change_icmp(struct pf_addr *ia, u_int16_t *ip, struct pf_addr *oa,
2200     struct pf_addr *na, u_int16_t np, u_int16_t *pc, u_int16_t *h2c,
2201     u_int16_t *ic, u_int16_t *hc, u_int8_t u, sa_family_t af)
2202 {
2203         struct pf_addr  oia, ooa;
2204
2205         PF_ACPY(&oia, ia, af);
2206         if (oa)
2207                 PF_ACPY(&ooa, oa, af);
2208
2209         /* Change inner protocol port, fix inner protocol checksum. */
2210         if (ip != NULL) {
2211                 u_int16_t       oip = *ip;
2212                 u_int32_t       opc;
2213
2214                 if (pc != NULL)
2215                         opc = *pc;
2216                 *ip = np;
2217                 if (pc != NULL)
2218                         *pc = pf_cksum_fixup(*pc, oip, *ip, u);
2219                 *ic = pf_cksum_fixup(*ic, oip, *ip, 0);
2220                 if (pc != NULL)
2221                         *ic = pf_cksum_fixup(*ic, opc, *pc, 0);
2222         }
2223         /* Change inner ip address, fix inner ip and icmp checksums. */
2224         PF_ACPY(ia, na, af);
2225         switch (af) {
2226 #ifdef INET
2227         case AF_INET: {
2228                 u_int32_t        oh2c = *h2c;
2229
2230                 *h2c = pf_cksum_fixup(pf_cksum_fixup(*h2c,
2231                     oia.addr16[0], ia->addr16[0], 0),
2232                     oia.addr16[1], ia->addr16[1], 0);
2233                 *ic = pf_cksum_fixup(pf_cksum_fixup(*ic,
2234                     oia.addr16[0], ia->addr16[0], 0),
2235                     oia.addr16[1], ia->addr16[1], 0);
2236                 *ic = pf_cksum_fixup(*ic, oh2c, *h2c, 0);
2237                 break;
2238         }
2239 #endif /* INET */
2240 #ifdef INET6
2241         case AF_INET6:
2242                 *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2243                     pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2244                     pf_cksum_fixup(pf_cksum_fixup(*ic,
2245                     oia.addr16[0], ia->addr16[0], u),
2246                     oia.addr16[1], ia->addr16[1], u),
2247                     oia.addr16[2], ia->addr16[2], u),
2248                     oia.addr16[3], ia->addr16[3], u),
2249                     oia.addr16[4], ia->addr16[4], u),
2250                     oia.addr16[5], ia->addr16[5], u),
2251                     oia.addr16[6], ia->addr16[6], u),
2252                     oia.addr16[7], ia->addr16[7], u);
2253                 break;
2254 #endif /* INET6 */
2255         }
2256         /* Outer ip address, fix outer ip or icmpv6 checksum, if necessary. */
2257         if (oa) {
2258                 PF_ACPY(oa, na, af);
2259                 switch (af) {
2260 #ifdef INET
2261                 case AF_INET:
2262                         *hc = pf_cksum_fixup(pf_cksum_fixup(*hc,
2263                             ooa.addr16[0], oa->addr16[0], 0),
2264                             ooa.addr16[1], oa->addr16[1], 0);
2265                         break;
2266 #endif /* INET */
2267 #ifdef INET6
2268                 case AF_INET6:
2269                         *ic = pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2270                             pf_cksum_fixup(pf_cksum_fixup(pf_cksum_fixup(
2271                             pf_cksum_fixup(pf_cksum_fixup(*ic,
2272                             ooa.addr16[0], oa->addr16[0], u),
2273                             ooa.addr16[1], oa->addr16[1], u),
2274                             ooa.addr16[2], oa->addr16[2], u),
2275                             ooa.addr16[3], oa->addr16[3], u),
2276                             ooa.addr16[4], oa->addr16[4], u),
2277                             ooa.addr16[5], oa->addr16[5], u),
2278                             ooa.addr16[6], oa->addr16[6], u),
2279                             ooa.addr16[7], oa->addr16[7], u);
2280                         break;
2281 #endif /* INET6 */
2282                 }
2283         }
2284 }
2285
2286
2287 /*
2288  * Need to modulate the sequence numbers in the TCP SACK option
2289  * (credits to Krzysztof Pfaff for report and patch)
2290  */
2291 static int
2292 pf_modulate_sack(struct mbuf *m, int off, struct pf_pdesc *pd,
2293     struct tcphdr *th, struct pf_state_peer *dst)
2294 {
2295         int hlen = (th->th_off << 2) - sizeof(*th), thoptlen = hlen;
2296         u_int8_t opts[TCP_MAXOLEN], *opt = opts;
2297         int copyback = 0, i, olen;
2298         struct sackblk sack;
2299
2300 #define TCPOLEN_SACKLEN (TCPOLEN_SACK + 2)
2301         if (hlen < TCPOLEN_SACKLEN ||
2302             !pf_pull_hdr(m, off + sizeof(*th), opts, hlen, NULL, NULL, pd->af))
2303                 return 0;
2304
2305         while (hlen >= TCPOLEN_SACKLEN) {
2306                 olen = opt[1];
2307                 switch (*opt) {
2308                 case TCPOPT_EOL:        /* FALLTHROUGH */
2309                 case TCPOPT_NOP:
2310                         opt++;
2311                         hlen--;
2312                         break;
2313                 case TCPOPT_SACK:
2314                         if (olen > hlen)
2315                                 olen = hlen;
2316                         if (olen >= TCPOLEN_SACKLEN) {
2317                                 for (i = 2; i + TCPOLEN_SACK <= olen;
2318                                     i += TCPOLEN_SACK) {
2319                                         memcpy(&sack, &opt[i], sizeof(sack));
2320                                         pf_change_proto_a(m, &sack.start, &th->th_sum,
2321                                             htonl(ntohl(sack.start) - dst->seqdiff), 0);
2322                                         pf_change_proto_a(m, &sack.end, &th->th_sum,
2323                                             htonl(ntohl(sack.end) - dst->seqdiff), 0);
2324                                         memcpy(&opt[i], &sack, sizeof(sack));
2325                                 }
2326                                 copyback = 1;
2327                         }
2328                         /* FALLTHROUGH */
2329                 default:
2330                         if (olen < 2)
2331                                 olen = 2;
2332                         hlen -= olen;
2333                         opt += olen;
2334                 }
2335         }
2336
2337         if (copyback)
2338                 m_copyback(m, off + sizeof(*th), thoptlen, (caddr_t)opts);
2339         return (copyback);
2340 }
2341
2342 static void
2343 pf_send_tcp(struct mbuf *replyto, const struct pf_rule *r, sa_family_t af,
2344     const struct pf_addr *saddr, const struct pf_addr *daddr,
2345     u_int16_t sport, u_int16_t dport, u_int32_t seq, u_int32_t ack,
2346     u_int8_t flags, u_int16_t win, u_int16_t mss, u_int8_t ttl, int tag,
2347     u_int16_t rtag, struct ifnet *ifp)
2348 {
2349         struct pf_send_entry *pfse;
2350         struct mbuf     *m;
2351         int              len, tlen;
2352 #ifdef INET
2353         struct ip       *h = NULL;
2354 #endif /* INET */
2355 #ifdef INET6
2356         struct ip6_hdr  *h6 = NULL;
2357 #endif /* INET6 */
2358         struct tcphdr   *th;
2359         char            *opt;
2360         struct pf_mtag  *pf_mtag;
2361
2362         len = 0;
2363         th = NULL;
2364
2365         /* maximum segment size tcp option */
2366         tlen = sizeof(struct tcphdr);
2367         if (mss)
2368                 tlen += 4;
2369
2370         switch (af) {
2371 #ifdef INET
2372         case AF_INET:
2373                 len = sizeof(struct ip) + tlen;
2374                 break;
2375 #endif /* INET */
2376 #ifdef INET6
2377         case AF_INET6:
2378                 len = sizeof(struct ip6_hdr) + tlen;
2379                 break;
2380 #endif /* INET6 */
2381         default:
2382                 panic("%s: unsupported af %d", __func__, af);
2383         }
2384
2385         /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2386         pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2387         if (pfse == NULL)
2388                 return;
2389         m = m_gethdr(M_NOWAIT, MT_DATA);
2390         if (m == NULL) {
2391                 free(pfse, M_PFTEMP);
2392                 return;
2393         }
2394 #ifdef MAC
2395         mac_netinet_firewall_send(m);
2396 #endif
2397         if ((pf_mtag = pf_get_mtag(m)) == NULL) {
2398                 free(pfse, M_PFTEMP);
2399                 m_freem(m);
2400                 return;
2401         }
2402         if (tag)
2403                 m->m_flags |= M_SKIP_FIREWALL;
2404         pf_mtag->tag = rtag;
2405
2406         if (r != NULL && r->rtableid >= 0)
2407                 M_SETFIB(m, r->rtableid);
2408
2409 #ifdef ALTQ
2410         if (r != NULL && r->qid) {
2411                 pf_mtag->qid = r->qid;
2412
2413                 /* add hints for ecn */
2414                 pf_mtag->hdr = mtod(m, struct ip *);
2415         }
2416 #endif /* ALTQ */
2417         m->m_data += max_linkhdr;
2418         m->m_pkthdr.len = m->m_len = len;
2419         m->m_pkthdr.rcvif = NULL;
2420         bzero(m->m_data, len);
2421         switch (af) {
2422 #ifdef INET
2423         case AF_INET:
2424                 h = mtod(m, struct ip *);
2425
2426                 /* IP header fields included in the TCP checksum */
2427                 h->ip_p = IPPROTO_TCP;
2428                 h->ip_len = htons(tlen);
2429                 h->ip_src.s_addr = saddr->v4.s_addr;
2430                 h->ip_dst.s_addr = daddr->v4.s_addr;
2431
2432                 th = (struct tcphdr *)((caddr_t)h + sizeof(struct ip));
2433                 break;
2434 #endif /* INET */
2435 #ifdef INET6
2436         case AF_INET6:
2437                 h6 = mtod(m, struct ip6_hdr *);
2438
2439                 /* IP header fields included in the TCP checksum */
2440                 h6->ip6_nxt = IPPROTO_TCP;
2441                 h6->ip6_plen = htons(tlen);
2442                 memcpy(&h6->ip6_src, &saddr->v6, sizeof(struct in6_addr));
2443                 memcpy(&h6->ip6_dst, &daddr->v6, sizeof(struct in6_addr));
2444
2445                 th = (struct tcphdr *)((caddr_t)h6 + sizeof(struct ip6_hdr));
2446                 break;
2447 #endif /* INET6 */
2448         }
2449
2450         /* TCP header */
2451         th->th_sport = sport;
2452         th->th_dport = dport;
2453         th->th_seq = htonl(seq);
2454         th->th_ack = htonl(ack);
2455         th->th_off = tlen >> 2;
2456         th->th_flags = flags;
2457         th->th_win = htons(win);
2458
2459         if (mss) {
2460                 opt = (char *)(th + 1);
2461                 opt[0] = TCPOPT_MAXSEG;
2462                 opt[1] = 4;
2463                 HTONS(mss);
2464                 bcopy((caddr_t)&mss, (caddr_t)(opt + 2), 2);
2465         }
2466
2467         switch (af) {
2468 #ifdef INET
2469         case AF_INET:
2470                 /* TCP checksum */
2471                 th->th_sum = in_cksum(m, len);
2472
2473                 /* Finish the IP header */
2474                 h->ip_v = 4;
2475                 h->ip_hl = sizeof(*h) >> 2;
2476                 h->ip_tos = IPTOS_LOWDELAY;
2477                 h->ip_off = htons(V_path_mtu_discovery ? IP_DF : 0);
2478                 h->ip_len = htons(len);
2479                 h->ip_ttl = ttl ? ttl : V_ip_defttl;
2480                 h->ip_sum = 0;
2481
2482                 pfse->pfse_type = PFSE_IP;
2483                 break;
2484 #endif /* INET */
2485 #ifdef INET6
2486         case AF_INET6:
2487                 /* TCP checksum */
2488                 th->th_sum = in6_cksum(m, IPPROTO_TCP,
2489                     sizeof(struct ip6_hdr), tlen);
2490
2491                 h6->ip6_vfc |= IPV6_VERSION;
2492                 h6->ip6_hlim = IPV6_DEFHLIM;
2493
2494                 pfse->pfse_type = PFSE_IP6;
2495                 break;
2496 #endif /* INET6 */
2497         }
2498         pfse->pfse_m = m;
2499         pf_send(pfse);
2500 }
2501
2502 static void
2503 pf_return(struct pf_rule *r, struct pf_rule *nr, struct pf_pdesc *pd,
2504     struct pf_state_key *sk, int off, struct mbuf *m, struct tcphdr *th,
2505     struct pfi_kif *kif, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen,
2506     u_short *reason)
2507 {
2508         struct pf_addr  * const saddr = pd->src;
2509         struct pf_addr  * const daddr = pd->dst;
2510         sa_family_t      af = pd->af;
2511
2512         /* undo NAT changes, if they have taken place */
2513         if (nr != NULL) {
2514                 PF_ACPY(saddr, &sk->addr[pd->sidx], af);
2515                 PF_ACPY(daddr, &sk->addr[pd->didx], af);
2516                 if (pd->sport)
2517                         *pd->sport = sk->port[pd->sidx];
2518                 if (pd->dport)
2519                         *pd->dport = sk->port[pd->didx];
2520                 if (pd->proto_sum)
2521                         *pd->proto_sum = bproto_sum;
2522                 if (pd->ip_sum)
2523                         *pd->ip_sum = bip_sum;
2524                 m_copyback(m, off, hdrlen, pd->hdr.any);
2525         }
2526         if (pd->proto == IPPROTO_TCP &&
2527             ((r->rule_flag & PFRULE_RETURNRST) ||
2528             (r->rule_flag & PFRULE_RETURN)) &&
2529             !(th->th_flags & TH_RST)) {
2530                 u_int32_t        ack = ntohl(th->th_seq) + pd->p_len;
2531                 int              len = 0;
2532 #ifdef INET
2533                 struct ip       *h4;
2534 #endif
2535 #ifdef INET6
2536                 struct ip6_hdr  *h6;
2537 #endif
2538
2539                 switch (af) {
2540 #ifdef INET
2541                 case AF_INET:
2542                         h4 = mtod(m, struct ip *);
2543                         len = ntohs(h4->ip_len) - off;
2544                         break;
2545 #endif
2546 #ifdef INET6
2547                 case AF_INET6:
2548                         h6 = mtod(m, struct ip6_hdr *);
2549                         len = ntohs(h6->ip6_plen) - (off - sizeof(*h6));
2550                         break;
2551 #endif
2552                 }
2553
2554                 if (pf_check_proto_cksum(m, off, len, IPPROTO_TCP, af))
2555                         REASON_SET(reason, PFRES_PROTCKSUM);
2556                 else {
2557                         if (th->th_flags & TH_SYN)
2558                                 ack++;
2559                         if (th->th_flags & TH_FIN)
2560                                 ack++;
2561                         pf_send_tcp(m, r, af, pd->dst,
2562                                 pd->src, th->th_dport, th->th_sport,
2563                                 ntohl(th->th_ack), ack, TH_RST|TH_ACK, 0, 0,
2564                                 r->return_ttl, 1, 0, kif->pfik_ifp);
2565                 }
2566         } else if (pd->proto != IPPROTO_ICMP && af == AF_INET &&
2567                 r->return_icmp)
2568                 pf_send_icmp(m, r->return_icmp >> 8,
2569                         r->return_icmp & 255, af, r);
2570         else if (pd->proto != IPPROTO_ICMPV6 && af == AF_INET6 &&
2571                 r->return_icmp6)
2572                 pf_send_icmp(m, r->return_icmp6 >> 8,
2573                         r->return_icmp6 & 255, af, r);
2574 }
2575
2576
2577 static int
2578 pf_ieee8021q_setpcp(struct mbuf *m, u_int8_t prio)
2579 {
2580         struct m_tag *mtag;
2581
2582         KASSERT(prio <= PF_PRIO_MAX,
2583             ("%s with invalid pcp", __func__));
2584
2585         mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_OUT, NULL);
2586         if (mtag == NULL) {
2587                 mtag = m_tag_alloc(MTAG_8021Q, MTAG_8021Q_PCP_OUT,
2588                     sizeof(uint8_t), M_NOWAIT);
2589                 if (mtag == NULL)
2590                         return (ENOMEM);
2591                 m_tag_prepend(m, mtag);
2592         }
2593
2594         *(uint8_t *)(mtag + 1) = prio;
2595         return (0);
2596 }
2597
2598 static int
2599 pf_match_ieee8021q_pcp(u_int8_t prio, struct mbuf *m)
2600 {
2601         struct m_tag *mtag;
2602         u_int8_t mpcp;
2603
2604         mtag = m_tag_locate(m, MTAG_8021Q, MTAG_8021Q_PCP_IN, NULL);
2605         if (mtag == NULL)
2606                 return (0);
2607
2608         if (prio == PF_PRIO_ZERO)
2609                 prio = 0;
2610
2611         mpcp = *(uint8_t *)(mtag + 1);
2612
2613         return (mpcp == prio);
2614 }
2615
2616 static void
2617 pf_send_icmp(struct mbuf *m, u_int8_t type, u_int8_t code, sa_family_t af,
2618     struct pf_rule *r)
2619 {
2620         struct pf_send_entry *pfse;
2621         struct mbuf *m0;
2622         struct pf_mtag *pf_mtag;
2623
2624         /* Allocate outgoing queue entry, mbuf and mbuf tag. */
2625         pfse = malloc(sizeof(*pfse), M_PFTEMP, M_NOWAIT);
2626         if (pfse == NULL)
2627                 return;
2628
2629         if ((m0 = m_copypacket(m, M_NOWAIT)) == NULL) {
2630                 free(pfse, M_PFTEMP);
2631                 return;
2632         }
2633
2634         if ((pf_mtag = pf_get_mtag(m0)) == NULL) {
2635                 free(pfse, M_PFTEMP);
2636                 return;
2637         }
2638         /* XXX: revisit */
2639         m0->m_flags |= M_SKIP_FIREWALL;
2640
2641         if (r->rtableid >= 0)
2642                 M_SETFIB(m0, r->rtableid);
2643
2644 #ifdef ALTQ
2645         if (r->qid) {
2646                 pf_mtag->qid = r->qid;
2647                 /* add hints for ecn */
2648                 pf_mtag->hdr = mtod(m0, struct ip *);
2649         }
2650 #endif /* ALTQ */
2651
2652         switch (af) {
2653 #ifdef INET
2654         case AF_INET:
2655                 pfse->pfse_type = PFSE_ICMP;
2656                 break;
2657 #endif /* INET */
2658 #ifdef INET6
2659         case AF_INET6:
2660                 pfse->pfse_type = PFSE_ICMP6;
2661                 break;
2662 #endif /* INET6 */
2663         }
2664         pfse->pfse_m = m0;
2665         pfse->icmpopts.type = type;
2666         pfse->icmpopts.code = code;
2667         pf_send(pfse);
2668 }
2669
2670 /*
2671  * Return 1 if the addresses a and b match (with mask m), otherwise return 0.
2672  * If n is 0, they match if they are equal. If n is != 0, they match if they
2673  * are different.
2674  */
2675 int
2676 pf_match_addr(u_int8_t n, struct pf_addr *a, struct pf_addr *m,
2677     struct pf_addr *b, sa_family_t af)
2678 {
2679         int     match = 0;
2680
2681         switch (af) {
2682 #ifdef INET
2683         case AF_INET:
2684                 if ((a->addr32[0] & m->addr32[0]) ==
2685                     (b->addr32[0] & m->addr32[0]))
2686                         match++;
2687                 break;
2688 #endif /* INET */
2689 #ifdef INET6
2690         case AF_INET6:
2691                 if (((a->addr32[0] & m->addr32[0]) ==
2692                      (b->addr32[0] & m->addr32[0])) &&
2693                     ((a->addr32[1] & m->addr32[1]) ==
2694                      (b->addr32[1] & m->addr32[1])) &&
2695                     ((a->addr32[2] & m->addr32[2]) ==
2696                      (b->addr32[2] & m->addr32[2])) &&
2697                     ((a->addr32[3] & m->addr32[3]) ==
2698                      (b->addr32[3] & m->addr32[3])))
2699                         match++;
2700                 break;
2701 #endif /* INET6 */
2702         }
2703         if (match) {
2704                 if (n)
2705                         return (0);
2706                 else
2707                         return (1);
2708         } else {
2709                 if (n)
2710                         return (1);
2711                 else
2712                         return (0);
2713         }
2714 }
2715
2716 /*
2717  * Return 1 if b <= a <= e, otherwise return 0.
2718  */
2719 int
2720 pf_match_addr_range(struct pf_addr *b, struct pf_addr *e,
2721     struct pf_addr *a, sa_family_t af)
2722 {
2723         switch (af) {
2724 #ifdef INET
2725         case AF_INET:
2726                 if ((ntohl(a->addr32[0]) < ntohl(b->addr32[0])) ||
2727                     (ntohl(a->addr32[0]) > ntohl(e->addr32[0])))
2728                         return (0);
2729                 break;
2730 #endif /* INET */
2731 #ifdef INET6
2732         case AF_INET6: {
2733                 int     i;
2734
2735                 /* check a >= b */
2736                 for (i = 0; i < 4; ++i)
2737                         if (ntohl(a->addr32[i]) > ntohl(b->addr32[i]))
2738                                 break;
2739                         else if (ntohl(a->addr32[i]) < ntohl(b->addr32[i]))
2740                                 return (0);
2741                 /* check a <= e */
2742                 for (i = 0; i < 4; ++i)
2743                         if (ntohl(a->addr32[i]) < ntohl(e->addr32[i]))
2744                                 break;
2745                         else if (ntohl(a->addr32[i]) > ntohl(e->addr32[i]))
2746                                 return (0);
2747                 break;
2748         }
2749 #endif /* INET6 */
2750         }
2751         return (1);
2752 }
2753
2754 static int
2755 pf_match(u_int8_t op, u_int32_t a1, u_int32_t a2, u_int32_t p)
2756 {
2757         switch (op) {
2758         case PF_OP_IRG:
2759                 return ((p > a1) && (p < a2));
2760         case PF_OP_XRG:
2761                 return ((p < a1) || (p > a2));
2762         case PF_OP_RRG:
2763                 return ((p >= a1) && (p <= a2));
2764         case PF_OP_EQ:
2765                 return (p == a1);
2766         case PF_OP_NE:
2767                 return (p != a1);
2768         case PF_OP_LT:
2769                 return (p < a1);
2770         case PF_OP_LE:
2771                 return (p <= a1);
2772         case PF_OP_GT:
2773                 return (p > a1);
2774         case PF_OP_GE:
2775                 return (p >= a1);
2776         }
2777         return (0); /* never reached */
2778 }
2779
2780 int
2781 pf_match_port(u_int8_t op, u_int16_t a1, u_int16_t a2, u_int16_t p)
2782 {
2783         NTOHS(a1);
2784         NTOHS(a2);
2785         NTOHS(p);
2786         return (pf_match(op, a1, a2, p));
2787 }
2788
2789 static int
2790 pf_match_uid(u_int8_t op, uid_t a1, uid_t a2, uid_t u)
2791 {
2792         if (u == UID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2793                 return (0);
2794         return (pf_match(op, a1, a2, u));
2795 }
2796
2797 static int
2798 pf_match_gid(u_int8_t op, gid_t a1, gid_t a2, gid_t g)
2799 {
2800         if (g == GID_MAX && op != PF_OP_EQ && op != PF_OP_NE)
2801                 return (0);
2802         return (pf_match(op, a1, a2, g));
2803 }
2804
2805 int
2806 pf_match_tag(struct mbuf *m, struct pf_rule *r, int *tag, int mtag)
2807 {
2808         if (*tag == -1)
2809                 *tag = mtag;
2810
2811         return ((!r->match_tag_not && r->match_tag == *tag) ||
2812             (r->match_tag_not && r->match_tag != *tag));
2813 }
2814
2815 int
2816 pf_tag_packet(struct mbuf *m, struct pf_pdesc *pd, int tag)
2817 {
2818
2819         KASSERT(tag > 0, ("%s: tag %d", __func__, tag));
2820
2821         if (pd->pf_mtag == NULL && ((pd->pf_mtag = pf_get_mtag(m)) == NULL))
2822                 return (ENOMEM);
2823
2824         pd->pf_mtag->tag = tag;
2825
2826         return (0);
2827 }
2828
2829 #define PF_ANCHOR_STACKSIZE     32
2830 struct pf_anchor_stackframe {
2831         struct pf_ruleset       *rs;
2832         struct pf_rule          *r;     /* XXX: + match bit */
2833         struct pf_anchor        *child;
2834 };
2835
2836 /*
2837  * XXX: We rely on malloc(9) returning pointer aligned addresses.
2838  */
2839 #define PF_ANCHORSTACK_MATCH    0x00000001
2840 #define PF_ANCHORSTACK_MASK     (PF_ANCHORSTACK_MATCH)
2841
2842 #define PF_ANCHOR_MATCH(f)      ((uintptr_t)(f)->r & PF_ANCHORSTACK_MATCH)
2843 #define PF_ANCHOR_RULE(f)       (struct pf_rule *)                      \
2844                                 ((uintptr_t)(f)->r & ~PF_ANCHORSTACK_MASK)
2845 #define PF_ANCHOR_SET_MATCH(f)  do { (f)->r = (void *)                  \
2846                                 ((uintptr_t)(f)->r | PF_ANCHORSTACK_MATCH);  \
2847 } while (0)
2848
2849 void
2850 pf_step_into_anchor(struct pf_anchor_stackframe *stack, int *depth,
2851     struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2852     int *match)
2853 {
2854         struct pf_anchor_stackframe     *f;
2855
2856         PF_RULES_RASSERT();
2857
2858         if (match)
2859                 *match = 0;
2860         if (*depth >= PF_ANCHOR_STACKSIZE) {
2861                 printf("%s: anchor stack overflow on %s\n",
2862                     __func__, (*r)->anchor->name);
2863                 *r = TAILQ_NEXT(*r, entries);
2864                 return;
2865         } else if (*depth == 0 && a != NULL)
2866                 *a = *r;
2867         f = stack + (*depth)++;
2868         f->rs = *rs;
2869         f->r = *r;
2870         if ((*r)->anchor_wildcard) {
2871                 struct pf_anchor_node *parent = &(*r)->anchor->children;
2872
2873                 if ((f->child = RB_MIN(pf_anchor_node, parent)) == NULL) {
2874                         *r = NULL;
2875                         return;
2876                 }
2877                 *rs = &f->child->ruleset;
2878         } else {
2879                 f->child = NULL;
2880                 *rs = &(*r)->anchor->ruleset;
2881         }
2882         *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2883 }
2884
2885 int
2886 pf_step_out_of_anchor(struct pf_anchor_stackframe *stack, int *depth,
2887     struct pf_ruleset **rs, int n, struct pf_rule **r, struct pf_rule **a,
2888     int *match)
2889 {
2890         struct pf_anchor_stackframe     *f;
2891         struct pf_rule *fr;
2892         int quick = 0;
2893
2894         PF_RULES_RASSERT();
2895
2896         do {
2897                 if (*depth <= 0)
2898                         break;
2899                 f = stack + *depth - 1;
2900                 fr = PF_ANCHOR_RULE(f);
2901                 if (f->child != NULL) {
2902                         struct pf_anchor_node *parent;
2903
2904                         /*
2905                          * This block traverses through
2906                          * a wildcard anchor.
2907                          */
2908                         parent = &fr->anchor->children;
2909                         if (match != NULL && *match) {
2910                                 /*
2911                                  * If any of "*" matched, then
2912                                  * "foo/ *" matched, mark frame
2913                                  * appropriately.
2914                                  */
2915                                 PF_ANCHOR_SET_MATCH(f);
2916                                 *match = 0;
2917                         }
2918                         f->child = RB_NEXT(pf_anchor_node, parent, f->child);
2919                         if (f->child != NULL) {
2920                                 *rs = &f->child->ruleset;
2921                                 *r = TAILQ_FIRST((*rs)->rules[n].active.ptr);
2922                                 if (*r == NULL)
2923                                         continue;
2924                                 else
2925                                         break;
2926                         }
2927                 }
2928                 (*depth)--;
2929                 if (*depth == 0 && a != NULL)
2930                         *a = NULL;
2931                 *rs = f->rs;
2932                 if (PF_ANCHOR_MATCH(f) || (match != NULL && *match))
2933                         quick = fr->quick;
2934                 *r = TAILQ_NEXT(fr, entries);
2935         } while (*r == NULL);
2936
2937         return (quick);
2938 }
2939
2940 #ifdef INET6
2941 void
2942 pf_poolmask(struct pf_addr *naddr, struct pf_addr *raddr,
2943     struct pf_addr *rmask, struct pf_addr *saddr, sa_family_t af)
2944 {
2945         switch (af) {
2946 #ifdef INET
2947         case AF_INET:
2948                 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2949                 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2950                 break;
2951 #endif /* INET */
2952         case AF_INET6:
2953                 naddr->addr32[0] = (raddr->addr32[0] & rmask->addr32[0]) |
2954                 ((rmask->addr32[0] ^ 0xffffffff ) & saddr->addr32[0]);
2955                 naddr->addr32[1] = (raddr->addr32[1] & rmask->addr32[1]) |
2956                 ((rmask->addr32[1] ^ 0xffffffff ) & saddr->addr32[1]);
2957                 naddr->addr32[2] = (raddr->addr32[2] & rmask->addr32[2]) |
2958                 ((rmask->addr32[2] ^ 0xffffffff ) & saddr->addr32[2]);
2959                 naddr->addr32[3] = (raddr->addr32[3] & rmask->addr32[3]) |
2960                 ((rmask->addr32[3] ^ 0xffffffff ) & saddr->addr32[3]);
2961                 break;
2962         }
2963 }
2964
2965 void
2966 pf_addr_inc(struct pf_addr *addr, sa_family_t af)
2967 {
2968         switch (af) {
2969 #ifdef INET
2970         case AF_INET:
2971                 addr->addr32[0] = htonl(ntohl(addr->addr32[0]) + 1);
2972                 break;
2973 #endif /* INET */
2974         case AF_INET6:
2975                 if (addr->addr32[3] == 0xffffffff) {
2976                         addr->addr32[3] = 0;
2977                         if (addr->addr32[2] == 0xffffffff) {
2978                                 addr->addr32[2] = 0;
2979                                 if (addr->addr32[1] == 0xffffffff) {
2980                                         addr->addr32[1] = 0;
2981                                         addr->addr32[0] =
2982                                             htonl(ntohl(addr->addr32[0]) + 1);
2983                                 } else
2984                                         addr->addr32[1] =
2985                                             htonl(ntohl(addr->addr32[1]) + 1);
2986                         } else
2987                                 addr->addr32[2] =
2988                                     htonl(ntohl(addr->addr32[2]) + 1);
2989                 } else
2990                         addr->addr32[3] =
2991                             htonl(ntohl(addr->addr32[3]) + 1);
2992                 break;
2993         }
2994 }
2995 #endif /* INET6 */
2996
2997 int
2998 pf_socket_lookup(int direction, struct pf_pdesc *pd, struct mbuf *m)
2999 {
3000         struct pf_addr          *saddr, *daddr;
3001         u_int16_t                sport, dport;
3002         struct inpcbinfo        *pi;
3003         struct inpcb            *inp;
3004
3005         pd->lookup.uid = UID_MAX;
3006         pd->lookup.gid = GID_MAX;
3007
3008         switch (pd->proto) {
3009         case IPPROTO_TCP:
3010                 if (pd->hdr.tcp == NULL)
3011                         return (-1);
3012                 sport = pd->hdr.tcp->th_sport;
3013                 dport = pd->hdr.tcp->th_dport;
3014                 pi = &V_tcbinfo;
3015                 break;
3016         case IPPROTO_UDP:
3017                 if (pd->hdr.udp == NULL)
3018                         return (-1);
3019                 sport = pd->hdr.udp->uh_sport;
3020                 dport = pd->hdr.udp->uh_dport;
3021                 pi = &V_udbinfo;
3022                 break;
3023         default:
3024                 return (-1);
3025         }
3026         if (direction == PF_IN) {
3027                 saddr = pd->src;
3028                 daddr = pd->dst;
3029         } else {
3030                 u_int16_t       p;
3031
3032                 p = sport;
3033                 sport = dport;
3034                 dport = p;
3035                 saddr = pd->dst;
3036                 daddr = pd->src;
3037         }
3038         switch (pd->af) {
3039 #ifdef INET
3040         case AF_INET:
3041                 inp = in_pcblookup_mbuf(pi, saddr->v4, sport, daddr->v4,
3042                     dport, INPLOOKUP_RLOCKPCB, NULL, m);
3043                 if (inp == NULL) {
3044                         inp = in_pcblookup_mbuf(pi, saddr->v4, sport,
3045                            daddr->v4, dport, INPLOOKUP_WILDCARD |
3046                            INPLOOKUP_RLOCKPCB, NULL, m);
3047                         if (inp == NULL)
3048                                 return (-1);
3049                 }
3050                 break;
3051 #endif /* INET */
3052 #ifdef INET6
3053         case AF_INET6:
3054                 inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport, &daddr->v6,
3055                     dport, INPLOOKUP_RLOCKPCB, NULL, m);
3056                 if (inp == NULL) {
3057                         inp = in6_pcblookup_mbuf(pi, &saddr->v6, sport,
3058                             &daddr->v6, dport, INPLOOKUP_WILDCARD |
3059                             INPLOOKUP_RLOCKPCB, NULL, m);
3060                         if (inp == NULL)
3061                                 return (-1);
3062                 }
3063                 break;
3064 #endif /* INET6 */
3065
3066         default:
3067                 return (-1);
3068         }
3069         INP_RLOCK_ASSERT(inp);
3070         pd->lookup.uid = inp->inp_cred->cr_uid;
3071         pd->lookup.gid = inp->inp_cred->cr_groups[0];
3072         INP_RUNLOCK(inp);
3073
3074         return (1);
3075 }
3076
3077 static u_int8_t
3078 pf_get_wscale(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3079 {
3080         int              hlen;
3081         u_int8_t         hdr[60];
3082         u_int8_t        *opt, optlen;
3083         u_int8_t         wscale = 0;
3084
3085         hlen = th_off << 2;             /* hlen <= sizeof(hdr) */
3086         if (hlen <= sizeof(struct tcphdr))
3087                 return (0);
3088         if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3089                 return (0);
3090         opt = hdr + sizeof(struct tcphdr);
3091         hlen -= sizeof(struct tcphdr);
3092         while (hlen >= 3) {
3093                 switch (*opt) {
3094                 case TCPOPT_EOL:
3095                 case TCPOPT_NOP:
3096                         ++opt;
3097                         --hlen;
3098                         break;
3099                 case TCPOPT_WINDOW:
3100                         wscale = opt[2];
3101                         if (wscale > TCP_MAX_WINSHIFT)
3102                                 wscale = TCP_MAX_WINSHIFT;
3103                         wscale |= PF_WSCALE_FLAG;
3104                         /* FALLTHROUGH */
3105                 default:
3106                         optlen = opt[1];
3107                         if (optlen < 2)
3108                                 optlen = 2;
3109                         hlen -= optlen;
3110                         opt += optlen;
3111                         break;
3112                 }
3113         }
3114         return (wscale);
3115 }
3116
3117 static u_int16_t
3118 pf_get_mss(struct mbuf *m, int off, u_int16_t th_off, sa_family_t af)
3119 {
3120         int              hlen;
3121         u_int8_t         hdr[60];
3122         u_int8_t        *opt, optlen;
3123         u_int16_t        mss = V_tcp_mssdflt;
3124
3125         hlen = th_off << 2;     /* hlen <= sizeof(hdr) */
3126         if (hlen <= sizeof(struct tcphdr))
3127                 return (0);
3128         if (!pf_pull_hdr(m, off, hdr, hlen, NULL, NULL, af))
3129                 return (0);
3130         opt = hdr + sizeof(struct tcphdr);
3131         hlen -= sizeof(struct tcphdr);
3132         while (hlen >= TCPOLEN_MAXSEG) {
3133                 switch (*opt) {
3134                 case TCPOPT_EOL:
3135                 case TCPOPT_NOP:
3136                         ++opt;
3137                         --hlen;
3138                         break;
3139                 case TCPOPT_MAXSEG:
3140                         bcopy((caddr_t)(opt + 2), (caddr_t)&mss, 2);
3141                         NTOHS(mss);
3142                         /* FALLTHROUGH */
3143                 default:
3144                         optlen = opt[1];
3145                         if (optlen < 2)
3146                                 optlen = 2;
3147                         hlen -= optlen;
3148                         opt += optlen;
3149                         break;
3150                 }
3151         }
3152         return (mss);
3153 }
3154
3155 static u_int16_t
3156 pf_calc_mss(struct pf_addr *addr, sa_family_t af, int rtableid, u_int16_t offer)
3157 {
3158 #ifdef INET
3159         struct nhop4_basic      nh4;
3160 #endif /* INET */
3161 #ifdef INET6
3162         struct nhop6_basic      nh6;
3163         struct in6_addr         dst6;
3164         uint32_t                scopeid;
3165 #endif /* INET6 */
3166         int                      hlen = 0;
3167         uint16_t                 mss = 0;
3168
3169         switch (af) {
3170 #ifdef INET
3171         case AF_INET:
3172                 hlen = sizeof(struct ip);
3173                 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) == 0)
3174                         mss = nh4.nh_mtu - hlen - sizeof(struct tcphdr);
3175                 break;
3176 #endif /* INET */
3177 #ifdef INET6
3178         case AF_INET6:
3179                 hlen = sizeof(struct ip6_hdr);
3180                 in6_splitscope(&addr->v6, &dst6, &scopeid);
3181                 if (fib6_lookup_nh_basic(rtableid, &dst6, scopeid, 0,0,&nh6)==0)
3182                         mss = nh6.nh_mtu - hlen - sizeof(struct tcphdr);
3183                 break;
3184 #endif /* INET6 */
3185         }
3186
3187         mss = max(V_tcp_mssdflt, mss);
3188         mss = min(mss, offer);
3189         mss = max(mss, 64);             /* sanity - at least max opt space */
3190         return (mss);
3191 }
3192
3193 static u_int32_t
3194 pf_tcp_iss(struct pf_pdesc *pd)
3195 {
3196         MD5_CTX ctx;
3197         u_int32_t digest[4];
3198
3199         if (V_pf_tcp_secret_init == 0) {
3200                 read_random(&V_pf_tcp_secret, sizeof(V_pf_tcp_secret));
3201                 MD5Init(&V_pf_tcp_secret_ctx);
3202                 MD5Update(&V_pf_tcp_secret_ctx, V_pf_tcp_secret,
3203                     sizeof(V_pf_tcp_secret));
3204                 V_pf_tcp_secret_init = 1;
3205         }
3206
3207         ctx = V_pf_tcp_secret_ctx;
3208
3209         MD5Update(&ctx, (char *)&pd->hdr.tcp->th_sport, sizeof(u_short));
3210         MD5Update(&ctx, (char *)&pd->hdr.tcp->th_dport, sizeof(u_short));
3211         if (pd->af == AF_INET6) {
3212                 MD5Update(&ctx, (char *)&pd->src->v6, sizeof(struct in6_addr));
3213                 MD5Update(&ctx, (char *)&pd->dst->v6, sizeof(struct in6_addr));
3214         } else {
3215                 MD5Update(&ctx, (char *)&pd->src->v4, sizeof(struct in_addr));
3216                 MD5Update(&ctx, (char *)&pd->dst->v4, sizeof(struct in_addr));
3217         }
3218         MD5Final((u_char *)digest, &ctx);
3219         V_pf_tcp_iss_off += 4096;
3220 #define ISN_RANDOM_INCREMENT (4096 - 1)
3221         return (digest[0] + (arc4random() & ISN_RANDOM_INCREMENT) +
3222             V_pf_tcp_iss_off);
3223 #undef  ISN_RANDOM_INCREMENT
3224 }
3225
3226 static int
3227 pf_test_rule(struct pf_rule **rm, struct pf_state **sm, int direction,
3228     struct pfi_kif *kif, struct mbuf *m, int off, struct pf_pdesc *pd,
3229     struct pf_rule **am, struct pf_ruleset **rsm, struct inpcb *inp)
3230 {
3231         struct pf_rule          *nr = NULL;
3232         struct pf_addr          * const saddr = pd->src;
3233         struct pf_addr          * const daddr = pd->dst;
3234         sa_family_t              af = pd->af;
3235         struct pf_rule          *r, *a = NULL;
3236         struct pf_ruleset       *ruleset = NULL;
3237         struct pf_src_node      *nsn = NULL;
3238         struct tcphdr           *th = pd->hdr.tcp;
3239         struct pf_state_key     *sk = NULL, *nk = NULL;
3240         u_short                  reason;
3241         int                      rewrite = 0, hdrlen = 0;
3242         int                      tag = -1, rtableid = -1;
3243         int                      asd = 0;
3244         int                      match = 0;
3245         int                      state_icmp = 0;
3246         u_int16_t                sport = 0, dport = 0;
3247         u_int16_t                bproto_sum = 0, bip_sum = 0;
3248         u_int8_t                 icmptype = 0, icmpcode = 0;
3249         struct pf_anchor_stackframe     anchor_stack[PF_ANCHOR_STACKSIZE];
3250
3251         PF_RULES_RASSERT();
3252
3253         if (inp != NULL) {
3254                 INP_LOCK_ASSERT(inp);
3255                 pd->lookup.uid = inp->inp_cred->cr_uid;
3256                 pd->lookup.gid = inp->inp_cred->cr_groups[0];
3257                 pd->lookup.done = 1;
3258         }
3259
3260         switch (pd->proto) {
3261         case IPPROTO_TCP:
3262                 sport = th->th_sport;
3263                 dport = th->th_dport;
3264                 hdrlen = sizeof(*th);
3265                 break;
3266         case IPPROTO_UDP:
3267                 sport = pd->hdr.udp->uh_sport;
3268                 dport = pd->hdr.udp->uh_dport;
3269                 hdrlen = sizeof(*pd->hdr.udp);
3270                 break;
3271 #ifdef INET
3272         case IPPROTO_ICMP:
3273                 if (pd->af != AF_INET)
3274                         break;
3275                 sport = dport = pd->hdr.icmp->icmp_id;
3276                 hdrlen = sizeof(*pd->hdr.icmp);
3277                 icmptype = pd->hdr.icmp->icmp_type;
3278                 icmpcode = pd->hdr.icmp->icmp_code;
3279
3280                 if (icmptype == ICMP_UNREACH ||
3281                     icmptype == ICMP_SOURCEQUENCH ||
3282                     icmptype == ICMP_REDIRECT ||
3283                     icmptype == ICMP_TIMXCEED ||
3284                     icmptype == ICMP_PARAMPROB)
3285                         state_icmp++;
3286                 break;
3287 #endif /* INET */
3288 #ifdef INET6
3289         case IPPROTO_ICMPV6:
3290                 if (af != AF_INET6)
3291                         break;
3292                 sport = dport = pd->hdr.icmp6->icmp6_id;
3293                 hdrlen = sizeof(*pd->hdr.icmp6);
3294                 icmptype = pd->hdr.icmp6->icmp6_type;
3295                 icmpcode = pd->hdr.icmp6->icmp6_code;
3296
3297                 if (icmptype == ICMP6_DST_UNREACH ||
3298                     icmptype == ICMP6_PACKET_TOO_BIG ||
3299                     icmptype == ICMP6_TIME_EXCEEDED ||
3300                     icmptype == ICMP6_PARAM_PROB)
3301                         state_icmp++;
3302                 break;
3303 #endif /* INET6 */
3304         default:
3305                 sport = dport = hdrlen = 0;
3306                 break;
3307         }
3308
3309         r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3310
3311         /* check packet for BINAT/NAT/RDR */
3312         if ((nr = pf_get_translation(pd, m, off, direction, kif, &nsn, &sk,
3313             &nk, saddr, daddr, sport, dport, anchor_stack)) != NULL) {
3314                 KASSERT(sk != NULL, ("%s: null sk", __func__));
3315                 KASSERT(nk != NULL, ("%s: null nk", __func__));
3316
3317                 if (pd->ip_sum)
3318                         bip_sum = *pd->ip_sum;
3319
3320                 switch (pd->proto) {
3321                 case IPPROTO_TCP:
3322                         bproto_sum = th->th_sum;
3323                         pd->proto_sum = &th->th_sum;
3324
3325                         if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3326                             nk->port[pd->sidx] != sport) {
3327                                 pf_change_ap(m, saddr, &th->th_sport, pd->ip_sum,
3328                                     &th->th_sum, &nk->addr[pd->sidx],
3329                                     nk->port[pd->sidx], 0, af);
3330                                 pd->sport = &th->th_sport;
3331                                 sport = th->th_sport;
3332                         }
3333
3334                         if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3335                             nk->port[pd->didx] != dport) {
3336                                 pf_change_ap(m, daddr, &th->th_dport, pd->ip_sum,
3337                                     &th->th_sum, &nk->addr[pd->didx],
3338                                     nk->port[pd->didx], 0, af);
3339                                 dport = th->th_dport;
3340                                 pd->dport = &th->th_dport;
3341                         }
3342                         rewrite++;
3343                         break;
3344                 case IPPROTO_UDP:
3345                         bproto_sum = pd->hdr.udp->uh_sum;
3346                         pd->proto_sum = &pd->hdr.udp->uh_sum;
3347
3348                         if (PF_ANEQ(saddr, &nk->addr[pd->sidx], af) ||
3349                             nk->port[pd->sidx] != sport) {
3350                                 pf_change_ap(m, saddr, &pd->hdr.udp->uh_sport,
3351                                     pd->ip_sum, &pd->hdr.udp->uh_sum,
3352                                     &nk->addr[pd->sidx],
3353                                     nk->port[pd->sidx], 1, af);
3354                                 sport = pd->hdr.udp->uh_sport;
3355                                 pd->sport = &pd->hdr.udp->uh_sport;
3356                         }
3357
3358                         if (PF_ANEQ(daddr, &nk->addr[pd->didx], af) ||
3359                             nk->port[pd->didx] != dport) {
3360                                 pf_change_ap(m, daddr, &pd->hdr.udp->uh_dport,
3361                                     pd->ip_sum, &pd->hdr.udp->uh_sum,
3362                                     &nk->addr[pd->didx],
3363                                     nk->port[pd->didx], 1, af);
3364                                 dport = pd->hdr.udp->uh_dport;
3365                                 pd->dport = &pd->hdr.udp->uh_dport;
3366                         }
3367                         rewrite++;
3368                         break;
3369 #ifdef INET
3370                 case IPPROTO_ICMP:
3371                         nk->port[0] = nk->port[1];
3372                         if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET))
3373                                 pf_change_a(&saddr->v4.s_addr, pd->ip_sum,
3374                                     nk->addr[pd->sidx].v4.s_addr, 0);
3375
3376                         if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET))
3377                                 pf_change_a(&daddr->v4.s_addr, pd->ip_sum,
3378                                     nk->addr[pd->didx].v4.s_addr, 0);
3379
3380                         if (nk->port[1] != pd->hdr.icmp->icmp_id) {
3381                                 pd->hdr.icmp->icmp_cksum = pf_cksum_fixup(
3382                                     pd->hdr.icmp->icmp_cksum, sport,
3383                                     nk->port[1], 0);
3384                                 pd->hdr.icmp->icmp_id = nk->port[1];
3385                                 pd->sport = &pd->hdr.icmp->icmp_id;
3386                         }
3387                         m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
3388                         break;
3389 #endif /* INET */
3390 #ifdef INET6
3391                 case IPPROTO_ICMPV6:
3392                         nk->port[0] = nk->port[1];
3393                         if (PF_ANEQ(saddr, &nk->addr[pd->sidx], AF_INET6))
3394                                 pf_change_a6(saddr, &pd->hdr.icmp6->icmp6_cksum,
3395                                     &nk->addr[pd->sidx], 0);
3396
3397                         if (PF_ANEQ(daddr, &nk->addr[pd->didx], AF_INET6))
3398                                 pf_change_a6(daddr, &pd->hdr.icmp6->icmp6_cksum,
3399                                     &nk->addr[pd->didx], 0);
3400                         rewrite++;
3401                         break;
3402 #endif /* INET */
3403                 default:
3404                         switch (af) {
3405 #ifdef INET
3406                         case AF_INET:
3407                                 if (PF_ANEQ(saddr,
3408                                     &nk->addr[pd->sidx], AF_INET))
3409                                         pf_change_a(&saddr->v4.s_addr,
3410                                             pd->ip_sum,
3411                                             nk->addr[pd->sidx].v4.s_addr, 0);
3412
3413                                 if (PF_ANEQ(daddr,
3414                                     &nk->addr[pd->didx], AF_INET))
3415                                         pf_change_a(&daddr->v4.s_addr,
3416                                             pd->ip_sum,
3417                                             nk->addr[pd->didx].v4.s_addr, 0);
3418                                 break;
3419 #endif /* INET */
3420 #ifdef INET6
3421                         case AF_INET6:
3422                                 if (PF_ANEQ(saddr,
3423                                     &nk->addr[pd->sidx], AF_INET6))
3424                                         PF_ACPY(saddr, &nk->addr[pd->sidx], af);
3425
3426                                 if (PF_ANEQ(daddr,
3427                                     &nk->addr[pd->didx], AF_INET6))
3428                                         PF_ACPY(saddr, &nk->addr[pd->didx], af);
3429                                 break;
3430 #endif /* INET */
3431                         }
3432                         break;
3433                 }
3434                 if (nr->natpass)
3435                         r = NULL;
3436                 pd->nat_rule = nr;
3437         }
3438
3439         while (r != NULL) {
3440                 r->evaluations++;
3441                 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3442                         r = r->skip[PF_SKIP_IFP].ptr;
3443                 else if (r->direction && r->direction != direction)
3444                         r = r->skip[PF_SKIP_DIR].ptr;
3445                 else if (r->af && r->af != af)
3446                         r = r->skip[PF_SKIP_AF].ptr;
3447                 else if (r->proto && r->proto != pd->proto)
3448                         r = r->skip[PF_SKIP_PROTO].ptr;
3449                 else if (PF_MISMATCHAW(&r->src.addr, saddr, af,
3450                     r->src.neg, kif, M_GETFIB(m)))
3451                         r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3452                 /* tcp/udp only. port_op always 0 in other cases */
3453                 else if (r->src.port_op && !pf_match_port(r->src.port_op,
3454                     r->src.port[0], r->src.port[1], sport))
3455                         r = r->skip[PF_SKIP_SRC_PORT].ptr;
3456                 else if (PF_MISMATCHAW(&r->dst.addr, daddr, af,
3457                     r->dst.neg, NULL, M_GETFIB(m)))
3458                         r = r->skip[PF_SKIP_DST_ADDR].ptr;
3459                 /* tcp/udp only. port_op always 0 in other cases */
3460                 else if (r->dst.port_op && !pf_match_port(r->dst.port_op,
3461                     r->dst.port[0], r->dst.port[1], dport))
3462                         r = r->skip[PF_SKIP_DST_PORT].ptr;
3463                 /* icmp only. type always 0 in other cases */
3464                 else if (r->type && r->type != icmptype + 1)
3465                         r = TAILQ_NEXT(r, entries);
3466                 /* icmp only. type always 0 in other cases */
3467                 else if (r->code && r->code != icmpcode + 1)
3468                         r = TAILQ_NEXT(r, entries);
3469                 else if (r->tos && !(r->tos == pd->tos))
3470                         r = TAILQ_NEXT(r, entries);
3471                 else if (r->rule_flag & PFRULE_FRAGMENT)
3472                         r = TAILQ_NEXT(r, entries);
3473                 else if (pd->proto == IPPROTO_TCP &&
3474                     (r->flagset & th->th_flags) != r->flags)
3475                         r = TAILQ_NEXT(r, entries);
3476                 /* tcp/udp only. uid.op always 0 in other cases */
3477                 else if (r->uid.op && (pd->lookup.done || (pd->lookup.done =
3478                     pf_socket_lookup(direction, pd, m), 1)) &&
3479                     !pf_match_uid(r->uid.op, r->uid.uid[0], r->uid.uid[1],
3480                     pd->lookup.uid))
3481                         r = TAILQ_NEXT(r, entries);
3482                 /* tcp/udp only. gid.op always 0 in other cases */
3483                 else if (r->gid.op && (pd->lookup.done || (pd->lookup.done =
3484                     pf_socket_lookup(direction, pd, m), 1)) &&
3485                     !pf_match_gid(r->gid.op, r->gid.gid[0], r->gid.gid[1],
3486                     pd->lookup.gid))
3487                         r = TAILQ_NEXT(r, entries);
3488                 else if (r->prio &&
3489                     !pf_match_ieee8021q_pcp(r->prio, m))
3490                         r = TAILQ_NEXT(r, entries);
3491                 else if (r->prob &&
3492                     r->prob <= arc4random())
3493                         r = TAILQ_NEXT(r, entries);
3494                 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3495                     pd->pf_mtag ? pd->pf_mtag->tag : 0))
3496                         r = TAILQ_NEXT(r, entries);
3497                 else if (r->os_fingerprint != PF_OSFP_ANY &&
3498                     (pd->proto != IPPROTO_TCP || !pf_osfp_match(
3499                     pf_osfp_fingerprint(pd, m, off, th),
3500                     r->os_fingerprint)))
3501                         r = TAILQ_NEXT(r, entries);
3502                 else {
3503                         if (r->tag)
3504                                 tag = r->tag;
3505                         if (r->rtableid >= 0)
3506                                 rtableid = r->rtableid;
3507                         if (r->anchor == NULL) {
3508                                 match = 1;
3509                                 *rm = r;
3510                                 *am = a;
3511                                 *rsm = ruleset;
3512                                 if ((*rm)->quick)
3513                                         break;
3514                                 r = TAILQ_NEXT(r, entries);
3515                         } else
3516                                 pf_step_into_anchor(anchor_stack, &asd,
3517                                     &ruleset, PF_RULESET_FILTER, &r, &a,
3518                                     &match);
3519                 }
3520                 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3521                     &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3522                         break;
3523         }
3524         r = *rm;
3525         a = *am;
3526         ruleset = *rsm;
3527
3528         REASON_SET(&reason, PFRES_MATCH);
3529
3530         if (r->log || (nr != NULL && nr->log)) {
3531                 if (rewrite)
3532                         m_copyback(m, off, hdrlen, pd->hdr.any);
3533                 PFLOG_PACKET(kif, m, af, direction, reason, r->log ? r : nr, a,
3534                     ruleset, pd, 1);
3535         }
3536
3537         if ((r->action == PF_DROP) &&
3538             ((r->rule_flag & PFRULE_RETURNRST) ||
3539             (r->rule_flag & PFRULE_RETURNICMP) ||
3540             (r->rule_flag & PFRULE_RETURN))) {
3541                 pf_return(r, nr, pd, sk, off, m, th, kif, bproto_sum,
3542                     bip_sum, hdrlen, &reason);
3543         }
3544
3545         if (r->action == PF_DROP)
3546                 goto cleanup;
3547
3548         if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3549                 REASON_SET(&reason, PFRES_MEMORY);
3550                 goto cleanup;
3551         }
3552         if (rtableid >= 0)
3553                 M_SETFIB(m, rtableid);
3554
3555         if (!state_icmp && (r->keep_state || nr != NULL ||
3556             (pd->flags & PFDESC_TCP_NORM))) {
3557                 int action;
3558                 action = pf_create_state(r, nr, a, pd, nsn, nk, sk, m, off,
3559                     sport, dport, &rewrite, kif, sm, tag, bproto_sum, bip_sum,
3560                     hdrlen);
3561                 if (action != PF_PASS && r->rule_flag & PFRULE_RETURN) {
3562                         pf_return(r, nr, pd, sk, off, m, th, kif,
3563                             bproto_sum, bip_sum, hdrlen, &reason);
3564                         return (action);
3565                 }
3566         } else {
3567                 if (sk != NULL)
3568                         uma_zfree(V_pf_state_key_z, sk);
3569                 if (nk != NULL)
3570                         uma_zfree(V_pf_state_key_z, nk);
3571         }
3572
3573         /* copy back packet headers if we performed NAT operations */
3574         if (rewrite)
3575                 m_copyback(m, off, hdrlen, pd->hdr.any);
3576
3577         if (*sm != NULL && !((*sm)->state_flags & PFSTATE_NOSYNC) &&
3578             direction == PF_OUT &&
3579             pfsync_defer_ptr != NULL && pfsync_defer_ptr(*sm, m))
3580                 /*
3581                  * We want the state created, but we dont
3582                  * want to send this in case a partner
3583                  * firewall has to know about it to allow
3584                  * replies through it.
3585                  */
3586                 return (PF_DEFER);
3587
3588         return (PF_PASS);
3589
3590 cleanup:
3591         if (sk != NULL)
3592                 uma_zfree(V_pf_state_key_z, sk);
3593         if (nk != NULL)
3594                 uma_zfree(V_pf_state_key_z, nk);
3595         return (PF_DROP);
3596 }
3597
3598 static int
3599 pf_create_state(struct pf_rule *r, struct pf_rule *nr, struct pf_rule *a,
3600     struct pf_pdesc *pd, struct pf_src_node *nsn, struct pf_state_key *nk,
3601     struct pf_state_key *sk, struct mbuf *m, int off, u_int16_t sport,
3602     u_int16_t dport, int *rewrite, struct pfi_kif *kif, struct pf_state **sm,
3603     int tag, u_int16_t bproto_sum, u_int16_t bip_sum, int hdrlen)
3604 {
3605         struct pf_state         *s = NULL;
3606         struct pf_src_node      *sn = NULL;
3607         struct tcphdr           *th = pd->hdr.tcp;
3608         u_int16_t                mss = V_tcp_mssdflt;
3609         u_short                  reason;
3610
3611         /* check maximums */
3612         if (r->max_states &&
3613             (counter_u64_fetch(r->states_cur) >= r->max_states)) {
3614                 counter_u64_add(V_pf_status.lcounters[LCNT_STATES], 1);
3615                 REASON_SET(&reason, PFRES_MAXSTATES);
3616                 goto csfailed;
3617         }
3618         /* src node for filter rule */
3619         if ((r->rule_flag & PFRULE_SRCTRACK ||
3620             r->rpool.opts & PF_POOL_STICKYADDR) &&
3621             pf_insert_src_node(&sn, r, pd->src, pd->af) != 0) {
3622                 REASON_SET(&reason, PFRES_SRCLIMIT);
3623                 goto csfailed;
3624         }
3625         /* src node for translation rule */
3626         if (nr != NULL && (nr->rpool.opts & PF_POOL_STICKYADDR) &&
3627             pf_insert_src_node(&nsn, nr, &sk->addr[pd->sidx], pd->af)) {
3628                 REASON_SET(&reason, PFRES_SRCLIMIT);
3629                 goto csfailed;
3630         }
3631         s = uma_zalloc(V_pf_state_z, M_NOWAIT | M_ZERO);
3632         if (s == NULL) {
3633                 REASON_SET(&reason, PFRES_MEMORY);
3634                 goto csfailed;
3635         }
3636         s->rule.ptr = r;
3637         s->nat_rule.ptr = nr;
3638         s->anchor.ptr = a;
3639         STATE_INC_COUNTERS(s);
3640         if (r->allow_opts)
3641                 s->state_flags |= PFSTATE_ALLOWOPTS;
3642         if (r->rule_flag & PFRULE_STATESLOPPY)
3643                 s->state_flags |= PFSTATE_SLOPPY;
3644         s->log = r->log & PF_LOG_ALL;
3645         s->sync_state = PFSYNC_S_NONE;
3646         if (nr != NULL)
3647                 s->log |= nr->log & PF_LOG_ALL;
3648         switch (pd->proto) {
3649         case IPPROTO_TCP:
3650                 s->src.seqlo = ntohl(th->th_seq);
3651                 s->src.seqhi = s->src.seqlo + pd->p_len + 1;
3652                 if ((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN &&
3653                     r->keep_state == PF_STATE_MODULATE) {
3654                         /* Generate sequence number modulator */
3655                         if ((s->src.seqdiff = pf_tcp_iss(pd) - s->src.seqlo) ==
3656                             0)
3657                                 s->src.seqdiff = 1;
3658                         pf_change_proto_a(m, &th->th_seq, &th->th_sum,
3659                             htonl(s->src.seqlo + s->src.seqdiff), 0);
3660                         *rewrite = 1;
3661                 } else
3662                         s->src.seqdiff = 0;
3663                 if (th->th_flags & TH_SYN) {
3664                         s->src.seqhi++;
3665                         s->src.wscale = pf_get_wscale(m, off,
3666                             th->th_off, pd->af);
3667                 }
3668                 s->src.max_win = MAX(ntohs(th->th_win), 1);
3669                 if (s->src.wscale & PF_WSCALE_MASK) {
3670                         /* Remove scale factor from initial window */
3671                         int win = s->src.max_win;
3672                         win += 1 << (s->src.wscale & PF_WSCALE_MASK);
3673                         s->src.max_win = (win - 1) >>
3674                             (s->src.wscale & PF_WSCALE_MASK);
3675                 }
3676                 if (th->th_flags & TH_FIN)
3677                         s->src.seqhi++;
3678                 s->dst.seqhi = 1;
3679                 s->dst.max_win = 1;
3680                 s->src.state = TCPS_SYN_SENT;
3681                 s->dst.state = TCPS_CLOSED;
3682                 s->timeout = PFTM_TCP_FIRST_PACKET;
3683                 break;
3684         case IPPROTO_UDP:
3685                 s->src.state = PFUDPS_SINGLE;
3686                 s->dst.state = PFUDPS_NO_TRAFFIC;
3687                 s->timeout = PFTM_UDP_FIRST_PACKET;
3688                 break;
3689         case IPPROTO_ICMP:
3690 #ifdef INET6
3691         case IPPROTO_ICMPV6:
3692 #endif
3693                 s->timeout = PFTM_ICMP_FIRST_PACKET;
3694                 break;
3695         default:
3696                 s->src.state = PFOTHERS_SINGLE;
3697                 s->dst.state = PFOTHERS_NO_TRAFFIC;
3698                 s->timeout = PFTM_OTHER_FIRST_PACKET;
3699         }
3700
3701         if (r->rt) {
3702                 if (pf_map_addr(pd->af, r, pd->src, &s->rt_addr, NULL, &sn)) {
3703                         REASON_SET(&reason, PFRES_MAPFAILED);
3704                         pf_src_tree_remove_state(s);
3705                         STATE_DEC_COUNTERS(s);
3706                         uma_zfree(V_pf_state_z, s);
3707                         goto csfailed;
3708                 }
3709                 s->rt_kif = r->rpool.cur->kif;
3710         }
3711
3712         s->creation = time_uptime;
3713         s->expire = time_uptime;
3714
3715         if (sn != NULL)
3716                 s->src_node = sn;
3717         if (nsn != NULL) {
3718                 /* XXX We only modify one side for now. */
3719                 PF_ACPY(&nsn->raddr, &nk->addr[1], pd->af);
3720                 s->nat_src_node = nsn;
3721         }
3722         if (pd->proto == IPPROTO_TCP) {
3723                 if ((pd->flags & PFDESC_TCP_NORM) && pf_normalize_tcp_init(m,
3724                     off, pd, th, &s->src, &s->dst)) {
3725                         REASON_SET(&reason, PFRES_MEMORY);
3726                         pf_src_tree_remove_state(s);
3727                         STATE_DEC_COUNTERS(s);
3728                         uma_zfree(V_pf_state_z, s);
3729                         return (PF_DROP);
3730                 }
3731                 if ((pd->flags & PFDESC_TCP_NORM) && s->src.scrub &&
3732                     pf_normalize_tcp_stateful(m, off, pd, &reason, th, s,
3733                     &s->src, &s->dst, rewrite)) {
3734                         /* This really shouldn't happen!!! */
3735                         DPFPRINTF(PF_DEBUG_URGENT,
3736                             ("pf_normalize_tcp_stateful failed on first pkt"));
3737                         pf_normalize_tcp_cleanup(s);
3738                         pf_src_tree_remove_state(s);
3739                         STATE_DEC_COUNTERS(s);
3740                         uma_zfree(V_pf_state_z, s);
3741                         return (PF_DROP);
3742                 }
3743         }
3744         s->direction = pd->dir;
3745
3746         /*
3747          * sk/nk could already been setup by pf_get_translation().
3748          */
3749         if (nr == NULL) {
3750                 KASSERT((sk == NULL && nk == NULL), ("%s: nr %p sk %p, nk %p",
3751                     __func__, nr, sk, nk));
3752                 sk = pf_state_key_setup(pd, pd->src, pd->dst, sport, dport);
3753                 if (sk == NULL)
3754                         goto csfailed;
3755                 nk = sk;
3756         } else
3757                 KASSERT((sk != NULL && nk != NULL), ("%s: nr %p sk %p, nk %p",
3758                     __func__, nr, sk, nk));
3759
3760         /* Swap sk/nk for PF_OUT. */
3761         if (pf_state_insert(BOUND_IFACE(r, kif),
3762             (pd->dir == PF_IN) ? sk : nk,
3763             (pd->dir == PF_IN) ? nk : sk, s)) {
3764                 if (pd->proto == IPPROTO_TCP)
3765                         pf_normalize_tcp_cleanup(s);
3766                 REASON_SET(&reason, PFRES_STATEINS);
3767                 pf_src_tree_remove_state(s);
3768                 STATE_DEC_COUNTERS(s);
3769                 uma_zfree(V_pf_state_z, s);
3770                 return (PF_DROP);
3771         } else
3772                 *sm = s;
3773
3774         if (tag > 0)
3775                 s->tag = tag;
3776         if (pd->proto == IPPROTO_TCP && (th->th_flags & (TH_SYN|TH_ACK)) ==
3777             TH_SYN && r->keep_state == PF_STATE_SYNPROXY) {
3778                 s->src.state = PF_TCPS_PROXY_SRC;
3779                 /* undo NAT changes, if they have taken place */
3780                 if (nr != NULL) {
3781                         struct pf_state_key *skt = s->key[PF_SK_WIRE];
3782                         if (pd->dir == PF_OUT)
3783                                 skt = s->key[PF_SK_STACK];
3784                         PF_ACPY(pd->src, &skt->addr[pd->sidx], pd->af);
3785                         PF_ACPY(pd->dst, &skt->addr[pd->didx], pd->af);
3786                         if (pd->sport)
3787                                 *pd->sport = skt->port[pd->sidx];
3788                         if (pd->dport)
3789                                 *pd->dport = skt->port[pd->didx];
3790                         if (pd->proto_sum)
3791                                 *pd->proto_sum = bproto_sum;
3792                         if (pd->ip_sum)
3793                                 *pd->ip_sum = bip_sum;
3794                         m_copyback(m, off, hdrlen, pd->hdr.any);
3795                 }
3796                 s->src.seqhi = htonl(arc4random());
3797                 /* Find mss option */
3798                 int rtid = M_GETFIB(m);
3799                 mss = pf_get_mss(m, off, th->th_off, pd->af);
3800                 mss = pf_calc_mss(pd->src, pd->af, rtid, mss);
3801                 mss = pf_calc_mss(pd->dst, pd->af, rtid, mss);
3802                 s->src.mss = mss;
3803                 pf_send_tcp(NULL, r, pd->af, pd->dst, pd->src, th->th_dport,
3804                     th->th_sport, s->src.seqhi, ntohl(th->th_seq) + 1,
3805                     TH_SYN|TH_ACK, 0, s->src.mss, 0, 1, 0, NULL);
3806                 REASON_SET(&reason, PFRES_SYNPROXY);
3807                 return (PF_SYNPROXY_DROP);
3808         }
3809
3810         return (PF_PASS);
3811
3812 csfailed:
3813         if (sk != NULL)
3814                 uma_zfree(V_pf_state_key_z, sk);
3815         if (nk != NULL)
3816                 uma_zfree(V_pf_state_key_z, nk);
3817
3818         if (sn != NULL) {
3819                 struct pf_srchash *sh;
3820
3821                 sh = &V_pf_srchash[pf_hashsrc(&sn->addr, sn->af)];
3822                 PF_HASHROW_LOCK(sh);
3823                 if (--sn->states == 0 && sn->expire == 0) {
3824                         pf_unlink_src_node(sn);
3825                         uma_zfree(V_pf_sources_z, sn);
3826                         counter_u64_add(
3827                             V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3828                 }
3829                 PF_HASHROW_UNLOCK(sh);
3830         }
3831
3832         if (nsn != sn && nsn != NULL) {
3833                 struct pf_srchash *sh;
3834
3835                 sh = &V_pf_srchash[pf_hashsrc(&nsn->addr, nsn->af)];
3836                 PF_HASHROW_LOCK(sh);
3837                 if (--nsn->states == 0 && nsn->expire == 0) {
3838                         pf_unlink_src_node(nsn);
3839                         uma_zfree(V_pf_sources_z, nsn);
3840                         counter_u64_add(
3841                             V_pf_status.scounters[SCNT_SRC_NODE_REMOVALS], 1);
3842                 }
3843                 PF_HASHROW_UNLOCK(sh);
3844         }
3845
3846         return (PF_DROP);
3847 }
3848
3849 static int
3850 pf_test_fragment(struct pf_rule **rm, int direction, struct pfi_kif *kif,
3851     struct mbuf *m, void *h, struct pf_pdesc *pd, struct pf_rule **am,
3852     struct pf_ruleset **rsm)
3853 {
3854         struct pf_rule          *r, *a = NULL;
3855         struct pf_ruleset       *ruleset = NULL;
3856         sa_family_t              af = pd->af;
3857         u_short                  reason;
3858         int                      tag = -1;
3859         int                      asd = 0;
3860         int                      match = 0;
3861         struct pf_anchor_stackframe     anchor_stack[PF_ANCHOR_STACKSIZE];
3862
3863         PF_RULES_RASSERT();
3864
3865         r = TAILQ_FIRST(pf_main_ruleset.rules[PF_RULESET_FILTER].active.ptr);
3866         while (r != NULL) {
3867                 r->evaluations++;
3868                 if (pfi_kif_match(r->kif, kif) == r->ifnot)
3869                         r = r->skip[PF_SKIP_IFP].ptr;
3870                 else if (r->direction && r->direction != direction)
3871                         r = r->skip[PF_SKIP_DIR].ptr;
3872                 else if (r->af && r->af != af)
3873                         r = r->skip[PF_SKIP_AF].ptr;
3874                 else if (r->proto && r->proto != pd->proto)
3875                         r = r->skip[PF_SKIP_PROTO].ptr;
3876                 else if (PF_MISMATCHAW(&r->src.addr, pd->src, af,
3877                     r->src.neg, kif, M_GETFIB(m)))
3878                         r = r->skip[PF_SKIP_SRC_ADDR].ptr;
3879                 else if (PF_MISMATCHAW(&r->dst.addr, pd->dst, af,
3880                     r->dst.neg, NULL, M_GETFIB(m)))
3881                         r = r->skip[PF_SKIP_DST_ADDR].ptr;
3882                 else if (r->tos && !(r->tos == pd->tos))
3883                         r = TAILQ_NEXT(r, entries);
3884                 else if (r->os_fingerprint != PF_OSFP_ANY)
3885                         r = TAILQ_NEXT(r, entries);
3886                 else if (pd->proto == IPPROTO_UDP &&
3887                     (r->src.port_op || r->dst.port_op))
3888                         r = TAILQ_NEXT(r, entries);
3889                 else if (pd->proto == IPPROTO_TCP &&
3890                     (r->src.port_op || r->dst.port_op || r->flagset))
3891                         r = TAILQ_NEXT(r, entries);
3892                 else if ((pd->proto == IPPROTO_ICMP ||
3893                     pd->proto == IPPROTO_ICMPV6) &&
3894                     (r->type || r->code))
3895                         r = TAILQ_NEXT(r, entries);
3896                 else if (r->prio &&
3897                     !pf_match_ieee8021q_pcp(r->prio, m))
3898                         r = TAILQ_NEXT(r, entries);
3899                 else if (r->prob && r->prob <=
3900                     (arc4random() % (UINT_MAX - 1) + 1))
3901                         r = TAILQ_NEXT(r, entries);
3902                 else if (r->match_tag && !pf_match_tag(m, r, &tag,
3903                     pd->pf_mtag ? pd->pf_mtag->tag : 0))
3904                         r = TAILQ_NEXT(r, entries);
3905                 else {
3906                         if (r->anchor == NULL) {
3907                                 match = 1;
3908                                 *rm = r;
3909                                 *am = a;
3910                                 *rsm = ruleset;
3911                                 if ((*rm)->quick)
3912                                         break;
3913                                 r = TAILQ_NEXT(r, entries);
3914                         } else
3915                                 pf_step_into_anchor(anchor_stack, &asd,
3916                                     &ruleset, PF_RULESET_FILTER, &r, &a,
3917                                     &match);
3918                 }
3919                 if (r == NULL && pf_step_out_of_anchor(anchor_stack, &asd,
3920                     &ruleset, PF_RULESET_FILTER, &r, &a, &match))
3921                         break;
3922         }
3923         r = *rm;
3924         a = *am;
3925         ruleset = *rsm;
3926
3927         REASON_SET(&reason, PFRES_MATCH);
3928
3929         if (r->log)
3930                 PFLOG_PACKET(kif, m, af, direction, reason, r, a, ruleset, pd,
3931                     1);
3932
3933         if (r->action != PF_PASS)
3934                 return (PF_DROP);
3935
3936         if (tag > 0 && pf_tag_packet(m, pd, tag)) {
3937                 REASON_SET(&reason, PFRES_MEMORY);
3938                 return (PF_DROP);
3939         }
3940
3941         return (PF_PASS);
3942 }
3943
3944 static int
3945 pf_tcp_track_full(struct pf_state_peer *src, struct pf_state_peer *dst,
3946         struct pf_state **state, struct pfi_kif *kif, struct mbuf *m, int off,
3947         struct pf_pdesc *pd, u_short *reason, int *copyback)
3948 {
3949         struct tcphdr           *th = pd->hdr.tcp;
3950         u_int16_t                win = ntohs(th->th_win);
3951         u_int32_t                ack, end, seq, orig_seq;
3952         u_int8_t                 sws, dws;
3953         int                      ackskew;
3954
3955         if (src->wscale && dst->wscale && !(th->th_flags & TH_SYN)) {
3956                 sws = src->wscale & PF_WSCALE_MASK;
3957                 dws = dst->wscale & PF_WSCALE_MASK;
3958         } else
3959                 sws = dws = 0;
3960
3961         /*
3962          * Sequence tracking algorithm from Guido van Rooij's paper:
3963          *   http://www.madison-gurkha.com/publications/tcp_filtering/
3964          *      tcp_filtering.ps
3965          */
3966
3967         orig_seq = seq = ntohl(th->th_seq);
3968         if (src->seqlo == 0) {
3969                 /* First packet from this end. Set its state */
3970
3971                 if ((pd->flags & PFDESC_TCP_NORM || dst->scrub) &&
3972                     src->scrub == NULL) {
3973                         if (pf_normalize_tcp_init(m, off, pd, th, src, dst)) {
3974                                 REASON_SET(reason, PFRES_MEMORY);
3975                                 return (PF_DROP);
3976                         }
3977                 }
3978
3979                 /* Deferred generation of sequence number modulator */
3980                 if (dst->seqdiff && !src->seqdiff) {
3981                         /* use random iss for the TCP server */
3982                         while ((src->seqdiff = arc4random() - seq) == 0)
3983                                 ;
3984                         ack = ntohl(th->th_ack) - dst->seqdiff;
3985                         pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
3986                             src->seqdiff), 0);
3987                         pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
3988                         *copyback = 1;
3989                 } else {
3990                         ack = ntohl(th->th_ack);
3991                 }
3992
3993                 end = seq + pd->p_len;
3994                 if (th->th_flags & TH_SYN) {
3995                         end++;
3996                         if (dst->wscale & PF_WSCALE_FLAG) {
3997                                 src->wscale = pf_get_wscale(m, off, th->th_off,
3998                                     pd->af);
3999                                 if (src->wscale & PF_WSCALE_FLAG) {
4000                                         /* Remove scale factor from initial
4001                                          * window */
4002                                         sws = src->wscale & PF_WSCALE_MASK;
4003                                         win = ((u_int32_t)win + (1 << sws) - 1)
4004                                             >> sws;
4005                                         dws = dst->wscale & PF_WSCALE_MASK;
4006                                 } else {
4007                                         /* fixup other window */
4008                                         dst->max_win <<= dst->wscale &
4009                                             PF_WSCALE_MASK;
4010                                         /* in case of a retrans SYN|ACK */
4011                                         dst->wscale = 0;
4012                                 }
4013                         }
4014                 }
4015                 if (th->th_flags & TH_FIN)
4016                         end++;
4017
4018                 src->seqlo = seq;
4019                 if (src->state < TCPS_SYN_SENT)
4020                         src->state = TCPS_SYN_SENT;
4021
4022                 /*
4023                  * May need to slide the window (seqhi may have been set by
4024                  * the crappy stack check or if we picked up the connection
4025                  * after establishment)
4026                  */
4027                 if (src->seqhi == 1 ||
4028                     SEQ_GEQ(end + MAX(1, dst->max_win << dws), src->seqhi))
4029                         src->seqhi = end + MAX(1, dst->max_win << dws);
4030                 if (win > src->max_win)
4031                         src->max_win = win;
4032
4033         } else {
4034                 ack = ntohl(th->th_ack) - dst->seqdiff;
4035                 if (src->seqdiff) {
4036                         /* Modulate sequence numbers */
4037                         pf_change_proto_a(m, &th->th_seq, &th->th_sum, htonl(seq +
4038                             src->seqdiff), 0);
4039                         pf_change_proto_a(m, &th->th_ack, &th->th_sum, htonl(ack), 0);
4040                         *copyback = 1;
4041                 }
4042                 end = seq + pd->p_len;
4043                 if (th->th_flags & TH_SYN)
4044                         end++;
4045                 if (th->th_flags & TH_FIN)
4046                         end++;
4047         }
4048
4049         if ((th->th_flags & TH_ACK) == 0) {
4050                 /* Let it pass through the ack skew check */
4051                 ack = dst->seqlo;
4052         } else if ((ack == 0 &&
4053             (th->th_flags & (TH_ACK|TH_RST)) == (TH_ACK|TH_RST)) ||
4054             /* broken tcp stacks do not set ack */
4055             (dst->state < TCPS_SYN_SENT)) {
4056                 /*
4057                  * Many stacks (ours included) will set the ACK number in an
4058                  * FIN|ACK if the SYN times out -- no sequence to ACK.
4059                  */
4060                 ack = dst->seqlo;
4061         }
4062
4063         if (seq == end) {
4064                 /* Ease sequencing restrictions on no data packets */
4065                 seq = src->seqlo;
4066                 end = seq;
4067         }
4068
4069         ackskew = dst->seqlo - ack;
4070
4071
4072         /*
4073          * Need to demodulate the sequence numbers in any TCP SACK options
4074          * (Selective ACK). We could optionally validate the SACK values
4075          * against the current ACK window, either forwards or backwards, but
4076          * I'm not confident that SACK has been implemented properly
4077          * everywhere. It wouldn't surprise me if several stacks accidentally
4078          * SACK too far backwards of previously ACKed data. There really aren't
4079          * any security implications of bad SACKing unless the target stack
4080          * doesn't validate the option length correctly. Someone trying to
4081          * spoof into a TCP connection won't bother blindly sending SACK
4082          * options anyway.
4083          */
4084         if (dst->seqdiff && (th->th_off << 2) > sizeof(struct tcphdr)) {
4085                 if (pf_modulate_sack(m, off, pd, th, dst))
4086                         *copyback = 1;
4087         }
4088
4089
4090 #define MAXACKWINDOW (0xffff + 1500)    /* 1500 is an arbitrary fudge factor */
4091         if (SEQ_GEQ(src->seqhi, end) &&
4092             /* Last octet inside other's window space */
4093             SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) &&
4094             /* Retrans: not more than one window back */
4095             (ackskew >= -MAXACKWINDOW) &&
4096             /* Acking not more than one reassembled fragment backwards */
4097             (ackskew <= (MAXACKWINDOW << sws)) &&
4098             /* Acking not more than one window forward */
4099             ((th->th_flags & TH_RST) == 0 || orig_seq == src->seqlo ||
4100             (orig_seq == src->seqlo + 1) || (orig_seq + 1 == src->seqlo) ||
4101             (pd->flags & PFDESC_IP_REAS) == 0)) {
4102             /* Require an exact/+1 sequence match on resets when possible */
4103
4104                 if (dst->scrub || src->scrub) {
4105                         if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4106                             *state, src, dst, copyback))
4107                                 return (PF_DROP);
4108                 }
4109
4110                 /* update max window */
4111                 if (src->max_win < win)
4112                         src->max_win = win;
4113                 /* synchronize sequencing */
4114                 if (SEQ_GT(end, src->seqlo))
4115                         src->seqlo = end;
4116                 /* slide the window of what the other end can send */
4117                 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4118                         dst->seqhi = ack + MAX((win << sws), 1);
4119
4120
4121                 /* update states */
4122                 if (th->th_flags & TH_SYN)
4123                         if (src->state < TCPS_SYN_SENT)
4124                                 src->state = TCPS_SYN_SENT;
4125                 if (th->th_flags & TH_FIN)
4126                         if (src->state < TCPS_CLOSING)
4127                                 src->state = TCPS_CLOSING;
4128                 if (th->th_flags & TH_ACK) {
4129                         if (dst->state == TCPS_SYN_SENT) {
4130                                 dst->state = TCPS_ESTABLISHED;
4131                                 if (src->state == TCPS_ESTABLISHED &&
4132                                     (*state)->src_node != NULL &&
4133                                     pf_src_connlimit(state)) {
4134                                         REASON_SET(reason, PFRES_SRCLIMIT);
4135                                         return (PF_DROP);
4136                                 }
4137                         } else if (dst->state == TCPS_CLOSING)
4138                                 dst->state = TCPS_FIN_WAIT_2;
4139                 }
4140                 if (th->th_flags & TH_RST)
4141                         src->state = dst->state = TCPS_TIME_WAIT;
4142
4143                 /* update expire time */
4144                 (*state)->expire = time_uptime;
4145                 if (src->state >= TCPS_FIN_WAIT_2 &&
4146                     dst->state >= TCPS_FIN_WAIT_2)
4147                         (*state)->timeout = PFTM_TCP_CLOSED;
4148                 else if (src->state >= TCPS_CLOSING &&
4149                     dst->state >= TCPS_CLOSING)
4150                         (*state)->timeout = PFTM_TCP_FIN_WAIT;
4151                 else if (src->state < TCPS_ESTABLISHED ||
4152                     dst->state < TCPS_ESTABLISHED)
4153                         (*state)->timeout = PFTM_TCP_OPENING;
4154                 else if (src->state >= TCPS_CLOSING ||
4155                     dst->state >= TCPS_CLOSING)
4156                         (*state)->timeout = PFTM_TCP_CLOSING;
4157                 else
4158                         (*state)->timeout = PFTM_TCP_ESTABLISHED;
4159
4160                 /* Fall through to PASS packet */
4161
4162         } else if ((dst->state < TCPS_SYN_SENT ||
4163                 dst->state >= TCPS_FIN_WAIT_2 ||
4164                 src->state >= TCPS_FIN_WAIT_2) &&
4165             SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) &&
4166             /* Within a window forward of the originating packet */
4167             SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW)) {
4168             /* Within a window backward of the originating packet */
4169
4170                 /*
4171                  * This currently handles three situations:
4172                  *  1) Stupid stacks will shotgun SYNs before their peer
4173                  *     replies.
4174                  *  2) When PF catches an already established stream (the
4175                  *     firewall rebooted, the state table was flushed, routes
4176                  *     changed...)
4177                  *  3) Packets get funky immediately after the connection
4178                  *     closes (this should catch Solaris spurious ACK|FINs
4179                  *     that web servers like to spew after a close)
4180                  *
4181                  * This must be a little more careful than the above code
4182                  * since packet floods will also be caught here. We don't
4183                  * update the TTL here to mitigate the damage of a packet
4184                  * flood and so the same code can handle awkward establishment
4185                  * and a loosened connection close.
4186                  * In the establishment case, a correct peer response will
4187                  * validate the connection, go through the normal state code
4188                  * and keep updating the state TTL.
4189                  */
4190
4191                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4192                         printf("pf: loose state match: ");
4193                         pf_print_state(*state);
4194                         pf_print_flags(th->th_flags);
4195                         printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4196                             "pkts=%llu:%llu dir=%s,%s\n", seq, orig_seq, ack,
4197                             pd->p_len, ackskew, (unsigned long long)(*state)->packets[0],
4198                             (unsigned long long)(*state)->packets[1],
4199                             pd->dir == PF_IN ? "in" : "out",
4200                             pd->dir == (*state)->direction ? "fwd" : "rev");
4201                 }
4202
4203                 if (dst->scrub || src->scrub) {
4204                         if (pf_normalize_tcp_stateful(m, off, pd, reason, th,
4205                             *state, src, dst, copyback))
4206                                 return (PF_DROP);
4207                 }
4208
4209                 /* update max window */
4210                 if (src->max_win < win)
4211                         src->max_win = win;
4212                 /* synchronize sequencing */
4213                 if (SEQ_GT(end, src->seqlo))
4214                         src->seqlo = end;
4215                 /* slide the window of what the other end can send */
4216                 if (SEQ_GEQ(ack + (win << sws), dst->seqhi))
4217                         dst->seqhi = ack + MAX((win << sws), 1);
4218
4219                 /*
4220                  * Cannot set dst->seqhi here since this could be a shotgunned
4221                  * SYN and not an already established connection.
4222                  */
4223
4224                 if (th->th_flags & TH_FIN)
4225                         if (src->state < TCPS_CLOSING)
4226                                 src->state = TCPS_CLOSING;
4227                 if (th->th_flags & TH_RST)
4228                         src->state = dst->state = TCPS_TIME_WAIT;
4229
4230                 /* Fall through to PASS packet */
4231
4232         } else {
4233                 if ((*state)->dst.state == TCPS_SYN_SENT &&
4234                     (*state)->src.state == TCPS_SYN_SENT) {
4235                         /* Send RST for state mismatches during handshake */
4236                         if (!(th->th_flags & TH_RST))
4237                                 pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4238                                     pd->dst, pd->src, th->th_dport,
4239                                     th->th_sport, ntohl(th->th_ack), 0,
4240                                     TH_RST, 0, 0,
4241                                     (*state)->rule.ptr->return_ttl, 1, 0,
4242                                     kif->pfik_ifp);
4243                         src->seqlo = 0;
4244                         src->seqhi = 1;
4245                         src->max_win = 1;
4246                 } else if (V_pf_status.debug >= PF_DEBUG_MISC) {
4247                         printf("pf: BAD state: ");
4248                         pf_print_state(*state);
4249                         pf_print_flags(th->th_flags);
4250                         printf(" seq=%u (%u) ack=%u len=%u ackskew=%d "
4251                             "pkts=%llu:%llu dir=%s,%s\n",
4252                             seq, orig_seq, ack, pd->p_len, ackskew,
4253                             (unsigned long long)(*state)->packets[0],
4254                             (unsigned long long)(*state)->packets[1],
4255                             pd->dir == PF_IN ? "in" : "out",
4256                             pd->dir == (*state)->direction ? "fwd" : "rev");
4257                         printf("pf: State failure on: %c %c %c %c | %c %c\n",
4258                             SEQ_GEQ(src->seqhi, end) ? ' ' : '1',
4259                             SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)) ?
4260                             ' ': '2',
4261                             (ackskew >= -MAXACKWINDOW) ? ' ' : '3',
4262                             (ackskew <= (MAXACKWINDOW << sws)) ? ' ' : '4',
4263                             SEQ_GEQ(src->seqhi + MAXACKWINDOW, end) ?' ' :'5',
4264                             SEQ_GEQ(seq, src->seqlo - MAXACKWINDOW) ?' ' :'6');
4265                 }
4266                 REASON_SET(reason, PFRES_BADSTATE);
4267                 return (PF_DROP);
4268         }
4269
4270         return (PF_PASS);
4271 }
4272
4273 static int
4274 pf_tcp_track_sloppy(struct pf_state_peer *src, struct pf_state_peer *dst,
4275         struct pf_state **state, struct pf_pdesc *pd, u_short *reason)
4276 {
4277         struct tcphdr           *th = pd->hdr.tcp;
4278
4279         if (th->th_flags & TH_SYN)
4280                 if (src->state < TCPS_SYN_SENT)
4281                         src->state = TCPS_SYN_SENT;
4282         if (th->th_flags & TH_FIN)
4283                 if (src->state < TCPS_CLOSING)
4284                         src->state = TCPS_CLOSING;
4285         if (th->th_flags & TH_ACK) {
4286                 if (dst->state == TCPS_SYN_SENT) {
4287                         dst->state = TCPS_ESTABLISHED;
4288                         if (src->state == TCPS_ESTABLISHED &&
4289                             (*state)->src_node != NULL &&
4290                             pf_src_connlimit(state)) {
4291                                 REASON_SET(reason, PFRES_SRCLIMIT);
4292                                 return (PF_DROP);
4293                         }
4294                 } else if (dst->state == TCPS_CLOSING) {
4295                         dst->state = TCPS_FIN_WAIT_2;
4296                 } else if (src->state == TCPS_SYN_SENT &&
4297                     dst->state < TCPS_SYN_SENT) {
4298                         /*
4299                          * Handle a special sloppy case where we only see one
4300                          * half of the connection. If there is a ACK after
4301                          * the initial SYN without ever seeing a packet from
4302                          * the destination, set the connection to established.
4303                          */
4304                         dst->state = src->state = TCPS_ESTABLISHED;
4305                         if ((*state)->src_node != NULL &&
4306                             pf_src_connlimit(state)) {
4307                                 REASON_SET(reason, PFRES_SRCLIMIT);
4308                                 return (PF_DROP);
4309                         }
4310                 } else if (src->state == TCPS_CLOSING &&
4311                     dst->state == TCPS_ESTABLISHED &&
4312                     dst->seqlo == 0) {
4313                         /*
4314                          * Handle the closing of half connections where we
4315                          * don't see the full bidirectional FIN/ACK+ACK
4316                          * handshake.
4317                          */
4318                         dst->state = TCPS_CLOSING;
4319                 }
4320         }
4321         if (th->th_flags & TH_RST)
4322                 src->state = dst->state = TCPS_TIME_WAIT;
4323
4324         /* update expire time */
4325         (*state)->expire = time_uptime;
4326         if (src->state >= TCPS_FIN_WAIT_2 &&
4327             dst->state >= TCPS_FIN_WAIT_2)
4328                 (*state)->timeout = PFTM_TCP_CLOSED;
4329         else if (src->state >= TCPS_CLOSING &&
4330             dst->state >= TCPS_CLOSING)
4331                 (*state)->timeout = PFTM_TCP_FIN_WAIT;
4332         else if (src->state < TCPS_ESTABLISHED ||
4333             dst->state < TCPS_ESTABLISHED)
4334                 (*state)->timeout = PFTM_TCP_OPENING;
4335         else if (src->state >= TCPS_CLOSING ||
4336             dst->state >= TCPS_CLOSING)
4337                 (*state)->timeout = PFTM_TCP_CLOSING;
4338         else
4339                 (*state)->timeout = PFTM_TCP_ESTABLISHED;
4340
4341         return (PF_PASS);
4342 }
4343
4344 static int
4345 pf_test_state_tcp(struct pf_state **state, int direction, struct pfi_kif *kif,
4346     struct mbuf *m, int off, void *h, struct pf_pdesc *pd,
4347     u_short *reason)
4348 {
4349         struct pf_state_key_cmp  key;
4350         struct tcphdr           *th = pd->hdr.tcp;
4351         int                      copyback = 0;
4352         struct pf_state_peer    *src, *dst;
4353         struct pf_state_key     *sk;
4354
4355         bzero(&key, sizeof(key));
4356         key.af = pd->af;
4357         key.proto = IPPROTO_TCP;
4358         if (direction == PF_IN) {       /* wire side, straight */
4359                 PF_ACPY(&key.addr[0], pd->src, key.af);
4360                 PF_ACPY(&key.addr[1], pd->dst, key.af);
4361                 key.port[0] = th->th_sport;
4362                 key.port[1] = th->th_dport;
4363         } else {                        /* stack side, reverse */
4364                 PF_ACPY(&key.addr[1], pd->src, key.af);
4365                 PF_ACPY(&key.addr[0], pd->dst, key.af);
4366                 key.port[1] = th->th_sport;
4367                 key.port[0] = th->th_dport;
4368         }
4369
4370         STATE_LOOKUP(kif, &key, direction, *state, pd);
4371
4372         if (direction == (*state)->direction) {
4373                 src = &(*state)->src;
4374                 dst = &(*state)->dst;
4375         } else {
4376                 src = &(*state)->dst;
4377                 dst = &(*state)->src;
4378         }
4379
4380         sk = (*state)->key[pd->didx];
4381
4382         if ((*state)->src.state == PF_TCPS_PROXY_SRC) {
4383                 if (direction != (*state)->direction) {
4384                         REASON_SET(reason, PFRES_SYNPROXY);
4385                         return (PF_SYNPROXY_DROP);
4386                 }
4387                 if (th->th_flags & TH_SYN) {
4388                         if (ntohl(th->th_seq) != (*state)->src.seqlo) {
4389                                 REASON_SET(reason, PFRES_SYNPROXY);
4390                                 return (PF_DROP);
4391                         }
4392                         pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4393                             pd->src, th->th_dport, th->th_sport,
4394                             (*state)->src.seqhi, ntohl(th->th_seq) + 1,
4395                             TH_SYN|TH_ACK, 0, (*state)->src.mss, 0, 1, 0, NULL);
4396                         REASON_SET(reason, PFRES_SYNPROXY);
4397                         return (PF_SYNPROXY_DROP);
4398                 } else if (!(th->th_flags & TH_ACK) ||
4399                     (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4400                     (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4401                         REASON_SET(reason, PFRES_SYNPROXY);
4402                         return (PF_DROP);
4403                 } else if ((*state)->src_node != NULL &&
4404                     pf_src_connlimit(state)) {
4405                         REASON_SET(reason, PFRES_SRCLIMIT);
4406                         return (PF_DROP);
4407                 } else
4408                         (*state)->src.state = PF_TCPS_PROXY_DST;
4409         }
4410         if ((*state)->src.state == PF_TCPS_PROXY_DST) {
4411                 if (direction == (*state)->direction) {
4412                         if (((th->th_flags & (TH_SYN|TH_ACK)) != TH_ACK) ||
4413                             (ntohl(th->th_ack) != (*state)->src.seqhi + 1) ||
4414                             (ntohl(th->th_seq) != (*state)->src.seqlo + 1)) {
4415                                 REASON_SET(reason, PFRES_SYNPROXY);
4416                                 return (PF_DROP);
4417                         }
4418                         (*state)->src.max_win = MAX(ntohs(th->th_win), 1);
4419                         if ((*state)->dst.seqhi == 1)
4420                                 (*state)->dst.seqhi = htonl(arc4random());
4421                         pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4422                             &sk->addr[pd->sidx], &sk->addr[pd->didx],
4423                             sk->port[pd->sidx], sk->port[pd->didx],
4424                             (*state)->dst.seqhi, 0, TH_SYN, 0,
4425                             (*state)->src.mss, 0, 0, (*state)->tag, NULL);
4426                         REASON_SET(reason, PFRES_SYNPROXY);
4427                         return (PF_SYNPROXY_DROP);
4428                 } else if (((th->th_flags & (TH_SYN|TH_ACK)) !=
4429                     (TH_SYN|TH_ACK)) ||
4430                     (ntohl(th->th_ack) != (*state)->dst.seqhi + 1)) {
4431                         REASON_SET(reason, PFRES_SYNPROXY);
4432                         return (PF_DROP);
4433                 } else {
4434                         (*state)->dst.max_win = MAX(ntohs(th->th_win), 1);
4435                         (*state)->dst.seqlo = ntohl(th->th_seq);
4436                         pf_send_tcp(NULL, (*state)->rule.ptr, pd->af, pd->dst,
4437                             pd->src, th->th_dport, th->th_sport,
4438                             ntohl(th->th_ack), ntohl(th->th_seq) + 1,
4439                             TH_ACK, (*state)->src.max_win, 0, 0, 0,
4440                             (*state)->tag, NULL);
4441                         pf_send_tcp(NULL, (*state)->rule.ptr, pd->af,
4442                             &sk->addr[pd->sidx], &sk->addr[pd->didx],
4443                             sk->port[pd->sidx], sk->port[pd->didx],
4444                             (*state)->src.seqhi + 1, (*state)->src.seqlo + 1,
4445                             TH_ACK, (*state)->dst.max_win, 0, 0, 1, 0, NULL);
4446                         (*state)->src.seqdiff = (*state)->dst.seqhi -
4447                             (*state)->src.seqlo;
4448                         (*state)->dst.seqdiff = (*state)->src.seqhi -
4449                             (*state)->dst.seqlo;
4450                         (*state)->src.seqhi = (*state)->src.seqlo +
4451                             (*state)->dst.max_win;
4452                         (*state)->dst.seqhi = (*state)->dst.seqlo +
4453                             (*state)->src.max_win;
4454                         (*state)->src.wscale = (*state)->dst.wscale = 0;
4455                         (*state)->src.state = (*state)->dst.state =
4456                             TCPS_ESTABLISHED;
4457                         REASON_SET(reason, PFRES_SYNPROXY);
4458                         return (PF_SYNPROXY_DROP);
4459                 }
4460         }
4461
4462         if (((th->th_flags & (TH_SYN|TH_ACK)) == TH_SYN) &&
4463             dst->state >= TCPS_FIN_WAIT_2 &&
4464             src->state >= TCPS_FIN_WAIT_2) {
4465                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4466                         printf("pf: state reuse ");
4467                         pf_print_state(*state);
4468                         pf_print_flags(th->th_flags);
4469                         printf("\n");
4470                 }
4471                 /* XXX make sure it's the same direction ?? */
4472                 (*state)->src.state = (*state)->dst.state = TCPS_CLOSED;
4473                 pf_unlink_state(*state, PF_ENTER_LOCKED);
4474                 *state = NULL;
4475                 return (PF_DROP);
4476         }
4477
4478         if ((*state)->state_flags & PFSTATE_SLOPPY) {
4479                 if (pf_tcp_track_sloppy(src, dst, state, pd, reason) == PF_DROP)
4480                         return (PF_DROP);
4481         } else {
4482                 if (pf_tcp_track_full(src, dst, state, kif, m, off, pd, reason,
4483                     &copyback) == PF_DROP)
4484                         return (PF_DROP);
4485         }
4486
4487         /* translate source/destination address, if necessary */
4488         if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4489                 struct pf_state_key *nk = (*state)->key[pd->didx];
4490
4491                 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4492                     nk->port[pd->sidx] != th->th_sport)
4493                         pf_change_ap(m, pd->src, &th->th_sport,
4494                             pd->ip_sum, &th->th_sum, &nk->addr[pd->sidx],
4495                             nk->port[pd->sidx], 0, pd->af);
4496
4497                 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4498                     nk->port[pd->didx] != th->th_dport)
4499                         pf_change_ap(m, pd->dst, &th->th_dport,
4500                             pd->ip_sum, &th->th_sum, &nk->addr[pd->didx],
4501                             nk->port[pd->didx], 0, pd->af);
4502                 copyback = 1;
4503         }
4504
4505         /* Copyback sequence modulation or stateful scrub changes if needed */
4506         if (copyback)
4507                 m_copyback(m, off, sizeof(*th), (caddr_t)th);
4508
4509         return (PF_PASS);
4510 }
4511
4512 static int
4513 pf_test_state_udp(struct pf_state **state, int direction, struct pfi_kif *kif,
4514     struct mbuf *m, int off, void *h, struct pf_pdesc *pd)
4515 {
4516         struct pf_state_peer    *src, *dst;
4517         struct pf_state_key_cmp  key;
4518         struct udphdr           *uh = pd->hdr.udp;
4519
4520         bzero(&key, sizeof(key));
4521         key.af = pd->af;
4522         key.proto = IPPROTO_UDP;
4523         if (direction == PF_IN) {       /* wire side, straight */
4524                 PF_ACPY(&key.addr[0], pd->src, key.af);
4525                 PF_ACPY(&key.addr[1], pd->dst, key.af);
4526                 key.port[0] = uh->uh_sport;
4527                 key.port[1] = uh->uh_dport;
4528         } else {                        /* stack side, reverse */
4529                 PF_ACPY(&key.addr[1], pd->src, key.af);
4530                 PF_ACPY(&key.addr[0], pd->dst, key.af);
4531                 key.port[1] = uh->uh_sport;
4532                 key.port[0] = uh->uh_dport;
4533         }
4534
4535         STATE_LOOKUP(kif, &key, direction, *state, pd);
4536
4537         if (direction == (*state)->direction) {
4538                 src = &(*state)->src;
4539                 dst = &(*state)->dst;
4540         } else {
4541                 src = &(*state)->dst;
4542                 dst = &(*state)->src;
4543         }
4544
4545         /* update states */
4546         if (src->state < PFUDPS_SINGLE)
4547                 src->state = PFUDPS_SINGLE;
4548         if (dst->state == PFUDPS_SINGLE)
4549                 dst->state = PFUDPS_MULTIPLE;
4550
4551         /* update expire time */
4552         (*state)->expire = time_uptime;
4553         if (src->state == PFUDPS_MULTIPLE && dst->state == PFUDPS_MULTIPLE)
4554                 (*state)->timeout = PFTM_UDP_MULTIPLE;
4555         else
4556                 (*state)->timeout = PFTM_UDP_SINGLE;
4557
4558         /* translate source/destination address, if necessary */
4559         if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4560                 struct pf_state_key *nk = (*state)->key[pd->didx];
4561
4562                 if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], pd->af) ||
4563                     nk->port[pd->sidx] != uh->uh_sport)
4564                         pf_change_ap(m, pd->src, &uh->uh_sport, pd->ip_sum,
4565                             &uh->uh_sum, &nk->addr[pd->sidx],
4566                             nk->port[pd->sidx], 1, pd->af);
4567
4568                 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], pd->af) ||
4569                     nk->port[pd->didx] != uh->uh_dport)
4570                         pf_change_ap(m, pd->dst, &uh->uh_dport, pd->ip_sum,
4571                             &uh->uh_sum, &nk->addr[pd->didx],
4572                             nk->port[pd->didx], 1, pd->af);
4573                 m_copyback(m, off, sizeof(*uh), (caddr_t)uh);
4574         }
4575
4576         return (PF_PASS);
4577 }
4578
4579 static int
4580 pf_test_state_icmp(struct pf_state **state, int direction, struct pfi_kif *kif,
4581     struct mbuf *m, int off, void *h, struct pf_pdesc *pd, u_short *reason)
4582 {
4583         struct pf_addr  *saddr = pd->src, *daddr = pd->dst;
4584         u_int16_t        icmpid = 0, *icmpsum;
4585         u_int8_t         icmptype;
4586         int              state_icmp = 0;
4587         struct pf_state_key_cmp key;
4588
4589         bzero(&key, sizeof(key));
4590         switch (pd->proto) {
4591 #ifdef INET
4592         case IPPROTO_ICMP:
4593                 icmptype = pd->hdr.icmp->icmp_type;
4594                 icmpid = pd->hdr.icmp->icmp_id;
4595                 icmpsum = &pd->hdr.icmp->icmp_cksum;
4596
4597                 if (icmptype == ICMP_UNREACH ||
4598                     icmptype == ICMP_SOURCEQUENCH ||
4599                     icmptype == ICMP_REDIRECT ||
4600                     icmptype == ICMP_TIMXCEED ||
4601                     icmptype == ICMP_PARAMPROB)
4602                         state_icmp++;
4603                 break;
4604 #endif /* INET */
4605 #ifdef INET6
4606         case IPPROTO_ICMPV6:
4607                 icmptype = pd->hdr.icmp6->icmp6_type;
4608                 icmpid = pd->hdr.icmp6->icmp6_id;
4609                 icmpsum = &pd->hdr.icmp6->icmp6_cksum;
4610
4611                 if (icmptype == ICMP6_DST_UNREACH ||
4612                     icmptype == ICMP6_PACKET_TOO_BIG ||
4613                     icmptype == ICMP6_TIME_EXCEEDED ||
4614                     icmptype == ICMP6_PARAM_PROB)
4615                         state_icmp++;
4616                 break;
4617 #endif /* INET6 */
4618         }
4619
4620         if (!state_icmp) {
4621
4622                 /*
4623                  * ICMP query/reply message not related to a TCP/UDP packet.
4624                  * Search for an ICMP state.
4625                  */
4626                 key.af = pd->af;
4627                 key.proto = pd->proto;
4628                 key.port[0] = key.port[1] = icmpid;
4629                 if (direction == PF_IN) {       /* wire side, straight */
4630                         PF_ACPY(&key.addr[0], pd->src, key.af);
4631                         PF_ACPY(&key.addr[1], pd->dst, key.af);
4632                 } else {                        /* stack side, reverse */
4633                         PF_ACPY(&key.addr[1], pd->src, key.af);
4634                         PF_ACPY(&key.addr[0], pd->dst, key.af);
4635                 }
4636
4637                 STATE_LOOKUP(kif, &key, direction, *state, pd);
4638
4639                 (*state)->expire = time_uptime;
4640                 (*state)->timeout = PFTM_ICMP_ERROR_REPLY;
4641
4642                 /* translate source/destination address, if necessary */
4643                 if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
4644                         struct pf_state_key *nk = (*state)->key[pd->didx];
4645
4646                         switch (pd->af) {
4647 #ifdef INET
4648                         case AF_INET:
4649                                 if (PF_ANEQ(pd->src,
4650                                     &nk->addr[pd->sidx], AF_INET))
4651                                         pf_change_a(&saddr->v4.s_addr,
4652                                             pd->ip_sum,
4653                                             nk->addr[pd->sidx].v4.s_addr, 0);
4654
4655                                 if (PF_ANEQ(pd->dst, &nk->addr[pd->didx],
4656                                     AF_INET))
4657                                         pf_change_a(&daddr->v4.s_addr,
4658                                             pd->ip_sum,
4659                                             nk->addr[pd->didx].v4.s_addr, 0);
4660
4661                                 if (nk->port[0] !=
4662                                     pd->hdr.icmp->icmp_id) {
4663                                         pd->hdr.icmp->icmp_cksum =
4664                                             pf_cksum_fixup(
4665                                             pd->hdr.icmp->icmp_cksum, icmpid,
4666                                             nk->port[pd->sidx], 0);
4667                                         pd->hdr.icmp->icmp_id =
4668                                             nk->port[pd->sidx];
4669                                 }
4670
4671                                 m_copyback(m, off, ICMP_MINLEN,
4672                                     (caddr_t )pd->hdr.icmp);
4673                                 break;
4674 #endif /* INET */
4675 #ifdef INET6
4676                         case AF_INET6:
4677                                 if (PF_ANEQ(pd->src,
4678                                     &nk->addr[pd->sidx], AF_INET6))
4679                                         pf_change_a6(saddr,
4680                                             &pd->hdr.icmp6->icmp6_cksum,
4681                                             &nk->addr[pd->sidx], 0);
4682
4683                                 if (PF_ANEQ(pd->dst,
4684                                     &nk->addr[pd->didx], AF_INET6))
4685                                         pf_change_a6(daddr,
4686                                             &pd->hdr.icmp6->icmp6_cksum,
4687                                             &nk->addr[pd->didx], 0);
4688
4689                                 m_copyback(m, off, sizeof(struct icmp6_hdr),
4690                                     (caddr_t )pd->hdr.icmp6);
4691                                 break;
4692 #endif /* INET6 */
4693                         }
4694                 }
4695                 return (PF_PASS);
4696
4697         } else {
4698                 /*
4699                  * ICMP error message in response to a TCP/UDP packet.
4700                  * Extract the inner TCP/UDP header and search for that state.
4701                  */
4702
4703                 struct pf_pdesc pd2;
4704                 bzero(&pd2, sizeof pd2);
4705 #ifdef INET
4706                 struct ip       h2;
4707 #endif /* INET */
4708 #ifdef INET6
4709                 struct ip6_hdr  h2_6;
4710                 int             terminal = 0;
4711 #endif /* INET6 */
4712                 int             ipoff2 = 0;
4713                 int             off2 = 0;
4714
4715                 pd2.af = pd->af;
4716                 /* Payload packet is from the opposite direction. */
4717                 pd2.sidx = (direction == PF_IN) ? 1 : 0;
4718                 pd2.didx = (direction == PF_IN) ? 0 : 1;
4719                 switch (pd->af) {
4720 #ifdef INET
4721                 case AF_INET:
4722                         /* offset of h2 in mbuf chain */
4723                         ipoff2 = off + ICMP_MINLEN;
4724
4725                         if (!pf_pull_hdr(m, ipoff2, &h2, sizeof(h2),
4726                             NULL, reason, pd2.af)) {
4727                                 DPFPRINTF(PF_DEBUG_MISC,
4728                                     ("pf: ICMP error message too short "
4729                                     "(ip)\n"));
4730                                 return (PF_DROP);
4731                         }
4732                         /*
4733                          * ICMP error messages don't refer to non-first
4734                          * fragments
4735                          */
4736                         if (h2.ip_off & htons(IP_OFFMASK)) {
4737                                 REASON_SET(reason, PFRES_FRAG);
4738                                 return (PF_DROP);
4739                         }
4740
4741                         /* offset of protocol header that follows h2 */
4742                         off2 = ipoff2 + (h2.ip_hl << 2);
4743
4744                         pd2.proto = h2.ip_p;
4745                         pd2.src = (struct pf_addr *)&h2.ip_src;
4746                         pd2.dst = (struct pf_addr *)&h2.ip_dst;
4747                         pd2.ip_sum = &h2.ip_sum;
4748                         break;
4749 #endif /* INET */
4750 #ifdef INET6
4751                 case AF_INET6:
4752                         ipoff2 = off + sizeof(struct icmp6_hdr);
4753
4754                         if (!pf_pull_hdr(m, ipoff2, &h2_6, sizeof(h2_6),
4755                             NULL, reason, pd2.af)) {
4756                                 DPFPRINTF(PF_DEBUG_MISC,
4757                                     ("pf: ICMP error message too short "
4758                                     "(ip6)\n"));
4759                                 return (PF_DROP);
4760                         }
4761                         pd2.proto = h2_6.ip6_nxt;
4762                         pd2.src = (struct pf_addr *)&h2_6.ip6_src;
4763                         pd2.dst = (struct pf_addr *)&h2_6.ip6_dst;
4764                         pd2.ip_sum = NULL;
4765                         off2 = ipoff2 + sizeof(h2_6);
4766                         do {
4767                                 switch (pd2.proto) {
4768                                 case IPPROTO_FRAGMENT:
4769                                         /*
4770                                          * ICMPv6 error messages for
4771                                          * non-first fragments
4772                                          */
4773                                         REASON_SET(reason, PFRES_FRAG);
4774                                         return (PF_DROP);
4775                                 case IPPROTO_AH:
4776                                 case IPPROTO_HOPOPTS:
4777                                 case IPPROTO_ROUTING:
4778                                 case IPPROTO_DSTOPTS: {
4779                                         /* get next header and header length */
4780                                         struct ip6_ext opt6;
4781
4782                                         if (!pf_pull_hdr(m, off2, &opt6,
4783                                             sizeof(opt6), NULL, reason,
4784                                             pd2.af)) {
4785                                                 DPFPRINTF(PF_DEBUG_MISC,
4786                                                     ("pf: ICMPv6 short opt\n"));
4787                                                 return (PF_DROP);
4788                                         }
4789                                         if (pd2.proto == IPPROTO_AH)
4790                                                 off2 += (opt6.ip6e_len + 2) * 4;
4791                                         else
4792                                                 off2 += (opt6.ip6e_len + 1) * 8;
4793                                         pd2.proto = opt6.ip6e_nxt;
4794                                         /* goto the next header */
4795                                         break;
4796                                 }
4797                                 default:
4798                                         terminal++;
4799                                         break;
4800                                 }
4801                         } while (!terminal);
4802                         break;
4803 #endif /* INET6 */
4804                 }
4805
4806                 switch (pd2.proto) {
4807                 case IPPROTO_TCP: {
4808                         struct tcphdr            th;
4809                         u_int32_t                seq;
4810                         struct pf_state_peer    *src, *dst;
4811                         u_int8_t                 dws;
4812                         int                      copyback = 0;
4813
4814                         /*
4815                          * Only the first 8 bytes of the TCP header can be
4816                          * expected. Don't access any TCP header fields after
4817                          * th_seq, an ackskew test is not possible.
4818                          */
4819                         if (!pf_pull_hdr(m, off2, &th, 8, NULL, reason,
4820                             pd2.af)) {
4821                                 DPFPRINTF(PF_DEBUG_MISC,
4822                                     ("pf: ICMP error message too short "
4823                                     "(tcp)\n"));
4824                                 return (PF_DROP);
4825                         }
4826
4827                         key.af = pd2.af;
4828                         key.proto = IPPROTO_TCP;
4829                         PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4830                         PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4831                         key.port[pd2.sidx] = th.th_sport;
4832                         key.port[pd2.didx] = th.th_dport;
4833
4834                         STATE_LOOKUP(kif, &key, direction, *state, pd);
4835
4836                         if (direction == (*state)->direction) {
4837                                 src = &(*state)->dst;
4838                                 dst = &(*state)->src;
4839                         } else {
4840                                 src = &(*state)->src;
4841                                 dst = &(*state)->dst;
4842                         }
4843
4844                         if (src->wscale && dst->wscale)
4845                                 dws = dst->wscale & PF_WSCALE_MASK;
4846                         else
4847                                 dws = 0;
4848
4849                         /* Demodulate sequence number */
4850                         seq = ntohl(th.th_seq) - src->seqdiff;
4851                         if (src->seqdiff) {
4852                                 pf_change_a(&th.th_seq, icmpsum,
4853                                     htonl(seq), 0);
4854                                 copyback = 1;
4855                         }
4856
4857                         if (!((*state)->state_flags & PFSTATE_SLOPPY) &&
4858                             (!SEQ_GEQ(src->seqhi, seq) ||
4859                             !SEQ_GEQ(seq, src->seqlo - (dst->max_win << dws)))) {
4860                                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4861                                         printf("pf: BAD ICMP %d:%d ",
4862                                             icmptype, pd->hdr.icmp->icmp_code);
4863                                         pf_print_host(pd->src, 0, pd->af);
4864                                         printf(" -> ");
4865                                         pf_print_host(pd->dst, 0, pd->af);
4866                                         printf(" state: ");
4867                                         pf_print_state(*state);
4868                                         printf(" seq=%u\n", seq);
4869                                 }
4870                                 REASON_SET(reason, PFRES_BADSTATE);
4871                                 return (PF_DROP);
4872                         } else {
4873                                 if (V_pf_status.debug >= PF_DEBUG_MISC) {
4874                                         printf("pf: OK ICMP %d:%d ",
4875                                             icmptype, pd->hdr.icmp->icmp_code);
4876                                         pf_print_host(pd->src, 0, pd->af);
4877                                         printf(" -> ");
4878                                         pf_print_host(pd->dst, 0, pd->af);
4879                                         printf(" state: ");
4880                                         pf_print_state(*state);
4881                                         printf(" seq=%u\n", seq);
4882                                 }
4883                         }
4884
4885                         /* translate source/destination address, if necessary */
4886                         if ((*state)->key[PF_SK_WIRE] !=
4887                             (*state)->key[PF_SK_STACK]) {
4888                                 struct pf_state_key *nk =
4889                                     (*state)->key[pd->didx];
4890
4891                                 if (PF_ANEQ(pd2.src,
4892                                     &nk->addr[pd2.sidx], pd2.af) ||
4893                                     nk->port[pd2.sidx] != th.th_sport)
4894                                         pf_change_icmp(pd2.src, &th.th_sport,
4895                                             daddr, &nk->addr[pd2.sidx],
4896                                             nk->port[pd2.sidx], NULL,
4897                                             pd2.ip_sum, icmpsum,
4898                                             pd->ip_sum, 0, pd2.af);
4899
4900                                 if (PF_ANEQ(pd2.dst,
4901                                     &nk->addr[pd2.didx], pd2.af) ||
4902                                     nk->port[pd2.didx] != th.th_dport)
4903                                         pf_change_icmp(pd2.dst, &th.th_dport,
4904                                             saddr, &nk->addr[pd2.didx],
4905                                             nk->port[pd2.didx], NULL,
4906                                             pd2.ip_sum, icmpsum,
4907                                             pd->ip_sum, 0, pd2.af);
4908                                 copyback = 1;
4909                         }
4910
4911                         if (copyback) {
4912                                 switch (pd2.af) {
4913 #ifdef INET
4914                                 case AF_INET:
4915                                         m_copyback(m, off, ICMP_MINLEN,
4916                                             (caddr_t )pd->hdr.icmp);
4917                                         m_copyback(m, ipoff2, sizeof(h2),
4918                                             (caddr_t )&h2);
4919                                         break;
4920 #endif /* INET */
4921 #ifdef INET6
4922                                 case AF_INET6:
4923                                         m_copyback(m, off,
4924                                             sizeof(struct icmp6_hdr),
4925                                             (caddr_t )pd->hdr.icmp6);
4926                                         m_copyback(m, ipoff2, sizeof(h2_6),
4927                                             (caddr_t )&h2_6);
4928                                         break;
4929 #endif /* INET6 */
4930                                 }
4931                                 m_copyback(m, off2, 8, (caddr_t)&th);
4932                         }
4933
4934                         return (PF_PASS);
4935                         break;
4936                 }
4937                 case IPPROTO_UDP: {
4938                         struct udphdr           uh;
4939
4940                         if (!pf_pull_hdr(m, off2, &uh, sizeof(uh),
4941                             NULL, reason, pd2.af)) {
4942                                 DPFPRINTF(PF_DEBUG_MISC,
4943                                     ("pf: ICMP error message too short "
4944                                     "(udp)\n"));
4945                                 return (PF_DROP);
4946                         }
4947
4948                         key.af = pd2.af;
4949                         key.proto = IPPROTO_UDP;
4950                         PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
4951                         PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
4952                         key.port[pd2.sidx] = uh.uh_sport;
4953                         key.port[pd2.didx] = uh.uh_dport;
4954
4955                         STATE_LOOKUP(kif, &key, direction, *state, pd);
4956
4957                         /* translate source/destination address, if necessary */
4958                         if ((*state)->key[PF_SK_WIRE] !=
4959                             (*state)->key[PF_SK_STACK]) {
4960                                 struct pf_state_key *nk =
4961                                     (*state)->key[pd->didx];
4962
4963                                 if (PF_ANEQ(pd2.src,
4964                                     &nk->addr[pd2.sidx], pd2.af) ||
4965                                     nk->port[pd2.sidx] != uh.uh_sport)
4966                                         pf_change_icmp(pd2.src, &uh.uh_sport,
4967                                             daddr, &nk->addr[pd2.sidx],
4968                                             nk->port[pd2.sidx], &uh.uh_sum,
4969                                             pd2.ip_sum, icmpsum,
4970                                             pd->ip_sum, 1, pd2.af);
4971
4972                                 if (PF_ANEQ(pd2.dst,
4973                                     &nk->addr[pd2.didx], pd2.af) ||
4974                                     nk->port[pd2.didx] != uh.uh_dport)
4975                                         pf_change_icmp(pd2.dst, &uh.uh_dport,
4976                                             saddr, &nk->addr[pd2.didx],
4977                                             nk->port[pd2.didx], &uh.uh_sum,
4978                                             pd2.ip_sum, icmpsum,
4979                                             pd->ip_sum, 1, pd2.af);
4980
4981                                 switch (pd2.af) {
4982 #ifdef INET
4983                                 case AF_INET:
4984                                         m_copyback(m, off, ICMP_MINLEN,
4985                                             (caddr_t )pd->hdr.icmp);
4986                                         m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
4987                                         break;
4988 #endif /* INET */
4989 #ifdef INET6
4990                                 case AF_INET6:
4991                                         m_copyback(m, off,
4992                                             sizeof(struct icmp6_hdr),
4993                                             (caddr_t )pd->hdr.icmp6);
4994                                         m_copyback(m, ipoff2, sizeof(h2_6),
4995                                             (caddr_t )&h2_6);
4996                                         break;
4997 #endif /* INET6 */
4998                                 }
4999                                 m_copyback(m, off2, sizeof(uh), (caddr_t)&uh);
5000                         }
5001                         return (PF_PASS);
5002                         break;
5003                 }
5004 #ifdef INET
5005                 case IPPROTO_ICMP: {
5006                         struct icmp             iih;
5007
5008                         if (!pf_pull_hdr(m, off2, &iih, ICMP_MINLEN,
5009                             NULL, reason, pd2.af)) {
5010                                 DPFPRINTF(PF_DEBUG_MISC,
5011                                     ("pf: ICMP error message too short i"
5012                                     "(icmp)\n"));
5013                                 return (PF_DROP);
5014                         }
5015
5016                         key.af = pd2.af;
5017                         key.proto = IPPROTO_ICMP;
5018                         PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5019                         PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5020                         key.port[0] = key.port[1] = iih.icmp_id;
5021
5022                         STATE_LOOKUP(kif, &key, direction, *state, pd);
5023
5024                         /* translate source/destination address, if necessary */
5025                         if ((*state)->key[PF_SK_WIRE] !=
5026                             (*state)->key[PF_SK_STACK]) {
5027                                 struct pf_state_key *nk =
5028                                     (*state)->key[pd->didx];
5029
5030                                 if (PF_ANEQ(pd2.src,
5031                                     &nk->addr[pd2.sidx], pd2.af) ||
5032                                     nk->port[pd2.sidx] != iih.icmp_id)
5033                                         pf_change_icmp(pd2.src, &iih.icmp_id,
5034                                             daddr, &nk->addr[pd2.sidx],
5035                                             nk->port[pd2.sidx], NULL,
5036                                             pd2.ip_sum, icmpsum,
5037                                             pd->ip_sum, 0, AF_INET);
5038
5039                                 if (PF_ANEQ(pd2.dst,
5040                                     &nk->addr[pd2.didx], pd2.af) ||
5041                                     nk->port[pd2.didx] != iih.icmp_id)
5042                                         pf_change_icmp(pd2.dst, &iih.icmp_id,
5043                                             saddr, &nk->addr[pd2.didx],
5044                                             nk->port[pd2.didx], NULL,
5045                                             pd2.ip_sum, icmpsum,
5046                                             pd->ip_sum, 0, AF_INET);
5047
5048                                 m_copyback(m, off, ICMP_MINLEN, (caddr_t)pd->hdr.icmp);
5049                                 m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5050                                 m_copyback(m, off2, ICMP_MINLEN, (caddr_t)&iih);
5051                         }
5052                         return (PF_PASS);
5053                         break;
5054                 }
5055 #endif /* INET */
5056 #ifdef INET6
5057                 case IPPROTO_ICMPV6: {
5058                         struct icmp6_hdr        iih;
5059
5060                         if (!pf_pull_hdr(m, off2, &iih,
5061                             sizeof(struct icmp6_hdr), NULL, reason, pd2.af)) {
5062                                 DPFPRINTF(PF_DEBUG_MISC,
5063                                     ("pf: ICMP error message too short "
5064                                     "(icmp6)\n"));
5065                                 return (PF_DROP);
5066                         }
5067
5068                         key.af = pd2.af;
5069                         key.proto = IPPROTO_ICMPV6;
5070                         PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5071                         PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5072                         key.port[0] = key.port[1] = iih.icmp6_id;
5073
5074                         STATE_LOOKUP(kif, &key, direction, *state, pd);
5075
5076                         /* translate source/destination address, if necessary */
5077                         if ((*state)->key[PF_SK_WIRE] !=
5078                             (*state)->key[PF_SK_STACK]) {
5079                                 struct pf_state_key *nk =
5080                                     (*state)->key[pd->didx];
5081
5082                                 if (PF_ANEQ(pd2.src,
5083                                     &nk->addr[pd2.sidx], pd2.af) ||
5084                                     nk->port[pd2.sidx] != iih.icmp6_id)
5085                                         pf_change_icmp(pd2.src, &iih.icmp6_id,
5086                                             daddr, &nk->addr[pd2.sidx],
5087                                             nk->port[pd2.sidx], NULL,
5088                                             pd2.ip_sum, icmpsum,
5089                                             pd->ip_sum, 0, AF_INET6);
5090
5091                                 if (PF_ANEQ(pd2.dst,
5092                                     &nk->addr[pd2.didx], pd2.af) ||
5093                                     nk->port[pd2.didx] != iih.icmp6_id)
5094                                         pf_change_icmp(pd2.dst, &iih.icmp6_id,
5095                                             saddr, &nk->addr[pd2.didx],
5096                                             nk->port[pd2.didx], NULL,
5097                                             pd2.ip_sum, icmpsum,
5098                                             pd->ip_sum, 0, AF_INET6);
5099
5100                                 m_copyback(m, off, sizeof(struct icmp6_hdr),
5101                                     (caddr_t)pd->hdr.icmp6);
5102                                 m_copyback(m, ipoff2, sizeof(h2_6), (caddr_t)&h2_6);
5103                                 m_copyback(m, off2, sizeof(struct icmp6_hdr),
5104                                     (caddr_t)&iih);
5105                         }
5106                         return (PF_PASS);
5107                         break;
5108                 }
5109 #endif /* INET6 */
5110                 default: {
5111                         key.af = pd2.af;
5112                         key.proto = pd2.proto;
5113                         PF_ACPY(&key.addr[pd2.sidx], pd2.src, key.af);
5114                         PF_ACPY(&key.addr[pd2.didx], pd2.dst, key.af);
5115                         key.port[0] = key.port[1] = 0;
5116
5117                         STATE_LOOKUP(kif, &key, direction, *state, pd);
5118
5119                         /* translate source/destination address, if necessary */
5120                         if ((*state)->key[PF_SK_WIRE] !=
5121                             (*state)->key[PF_SK_STACK]) {
5122                                 struct pf_state_key *nk =
5123                                     (*state)->key[pd->didx];
5124
5125                                 if (PF_ANEQ(pd2.src,
5126                                     &nk->addr[pd2.sidx], pd2.af))
5127                                         pf_change_icmp(pd2.src, NULL, daddr,
5128                                             &nk->addr[pd2.sidx], 0, NULL,
5129                                             pd2.ip_sum, icmpsum,
5130                                             pd->ip_sum, 0, pd2.af);
5131
5132                                 if (PF_ANEQ(pd2.dst,
5133                                     &nk->addr[pd2.didx], pd2.af))
5134                                         pf_change_icmp(pd2.dst, NULL, saddr,
5135                                             &nk->addr[pd2.didx], 0, NULL,
5136                                             pd2.ip_sum, icmpsum,
5137                                             pd->ip_sum, 0, pd2.af);
5138
5139                                 switch (pd2.af) {
5140 #ifdef INET
5141                                 case AF_INET:
5142                                         m_copyback(m, off, ICMP_MINLEN,
5143                                             (caddr_t)pd->hdr.icmp);
5144                                         m_copyback(m, ipoff2, sizeof(h2), (caddr_t)&h2);
5145                                         break;
5146 #endif /* INET */
5147 #ifdef INET6
5148                                 case AF_INET6:
5149                                         m_copyback(m, off,
5150                                             sizeof(struct icmp6_hdr),
5151                                             (caddr_t )pd->hdr.icmp6);
5152                                         m_copyback(m, ipoff2, sizeof(h2_6),
5153                                             (caddr_t )&h2_6);
5154                                         break;
5155 #endif /* INET6 */
5156                                 }
5157                         }
5158                         return (PF_PASS);
5159                         break;
5160                 }
5161                 }
5162         }
5163 }
5164
5165 static int
5166 pf_test_state_other(struct pf_state **state, int direction, struct pfi_kif *kif,
5167     struct mbuf *m, struct pf_pdesc *pd)
5168 {
5169         struct pf_state_peer    *src, *dst;
5170         struct pf_state_key_cmp  key;
5171
5172         bzero(&key, sizeof(key));
5173         key.af = pd->af;
5174         key.proto = pd->proto;
5175         if (direction == PF_IN) {
5176                 PF_ACPY(&key.addr[0], pd->src, key.af);
5177                 PF_ACPY(&key.addr[1], pd->dst, key.af);
5178                 key.port[0] = key.port[1] = 0;
5179         } else {
5180                 PF_ACPY(&key.addr[1], pd->src, key.af);
5181                 PF_ACPY(&key.addr[0], pd->dst, key.af);
5182                 key.port[1] = key.port[0] = 0;
5183         }
5184
5185         STATE_LOOKUP(kif, &key, direction, *state, pd);
5186
5187         if (direction == (*state)->direction) {
5188                 src = &(*state)->src;
5189                 dst = &(*state)->dst;
5190         } else {
5191                 src = &(*state)->dst;
5192                 dst = &(*state)->src;
5193         }
5194
5195         /* update states */
5196         if (src->state < PFOTHERS_SINGLE)
5197                 src->state = PFOTHERS_SINGLE;
5198         if (dst->state == PFOTHERS_SINGLE)
5199                 dst->state = PFOTHERS_MULTIPLE;
5200
5201         /* update expire time */
5202         (*state)->expire = time_uptime;
5203         if (src->state == PFOTHERS_MULTIPLE && dst->state == PFOTHERS_MULTIPLE)
5204                 (*state)->timeout = PFTM_OTHER_MULTIPLE;
5205         else
5206                 (*state)->timeout = PFTM_OTHER_SINGLE;
5207
5208         /* translate source/destination address, if necessary */
5209         if ((*state)->key[PF_SK_WIRE] != (*state)->key[PF_SK_STACK]) {
5210                 struct pf_state_key *nk = (*state)->key[pd->didx];
5211
5212                 KASSERT(nk, ("%s: nk is null", __func__));
5213                 KASSERT(pd, ("%s: pd is null", __func__));
5214                 KASSERT(pd->src, ("%s: pd->src is null", __func__));
5215                 KASSERT(pd->dst, ("%s: pd->dst is null", __func__));
5216                 switch (pd->af) {
5217 #ifdef INET
5218                 case AF_INET:
5219                         if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5220                                 pf_change_a(&pd->src->v4.s_addr,
5221                                     pd->ip_sum,
5222                                     nk->addr[pd->sidx].v4.s_addr,
5223                                     0);
5224
5225
5226                         if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5227                                 pf_change_a(&pd->dst->v4.s_addr,
5228                                     pd->ip_sum,
5229                                     nk->addr[pd->didx].v4.s_addr,
5230                                     0);
5231
5232                                 break;
5233 #endif /* INET */
5234 #ifdef INET6
5235                 case AF_INET6:
5236                         if (PF_ANEQ(pd->src, &nk->addr[pd->sidx], AF_INET))
5237                                 PF_ACPY(pd->src, &nk->addr[pd->sidx], pd->af);
5238
5239                         if (PF_ANEQ(pd->dst, &nk->addr[pd->didx], AF_INET))
5240                                 PF_ACPY(pd->dst, &nk->addr[pd->didx], pd->af);
5241 #endif /* INET6 */
5242                 }
5243         }
5244         return (PF_PASS);
5245 }
5246
5247 /*
5248  * ipoff and off are measured from the start of the mbuf chain.
5249  * h must be at "ipoff" on the mbuf chain.
5250  */
5251 void *
5252 pf_pull_hdr(struct mbuf *m, int off, void *p, int len,
5253     u_short *actionp, u_short *reasonp, sa_family_t af)
5254 {
5255         switch (af) {
5256 #ifdef INET
5257         case AF_INET: {
5258                 struct ip       *h = mtod(m, struct ip *);
5259                 u_int16_t        fragoff = (ntohs(h->ip_off) & IP_OFFMASK) << 3;
5260
5261                 if (fragoff) {
5262                         if (fragoff >= len)
5263                                 ACTION_SET(actionp, PF_PASS);
5264                         else {
5265                                 ACTION_SET(actionp, PF_DROP);
5266                                 REASON_SET(reasonp, PFRES_FRAG);
5267                         }
5268                         return (NULL);
5269                 }
5270                 if (m->m_pkthdr.len < off + len ||
5271                     ntohs(h->ip_len) < off + len) {
5272                         ACTION_SET(actionp, PF_DROP);
5273                         REASON_SET(reasonp, PFRES_SHORT);
5274                         return (NULL);
5275                 }
5276                 break;
5277         }
5278 #endif /* INET */
5279 #ifdef INET6
5280         case AF_INET6: {
5281                 struct ip6_hdr  *h = mtod(m, struct ip6_hdr *);
5282
5283                 if (m->m_pkthdr.len < off + len ||
5284                     (ntohs(h->ip6_plen) + sizeof(struct ip6_hdr)) <
5285                     (unsigned)(off + len)) {
5286                         ACTION_SET(actionp, PF_DROP);
5287                         REASON_SET(reasonp, PFRES_SHORT);
5288                         return (NULL);
5289                 }
5290                 break;
5291         }
5292 #endif /* INET6 */
5293         }
5294         m_copydata(m, off, len, p);
5295         return (p);
5296 }
5297
5298 #ifdef RADIX_MPATH
5299 static int
5300 pf_routable_oldmpath(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5301     int rtableid)
5302 {
5303         struct radix_node_head  *rnh;
5304         struct sockaddr_in      *dst;
5305         int                      ret = 1;
5306         int                      check_mpath;
5307 #ifdef INET6
5308         struct sockaddr_in6     *dst6;
5309         struct route_in6         ro;
5310 #else
5311         struct route             ro;
5312 #endif
5313         struct radix_node       *rn;
5314         struct rtentry          *rt;
5315         struct ifnet            *ifp;
5316
5317         check_mpath = 0;
5318         /* XXX: stick to table 0 for now */
5319         rnh = rt_tables_get_rnh(0, af);
5320         if (rnh != NULL && rn_mpath_capable(rnh))
5321                 check_mpath = 1;
5322         bzero(&ro, sizeof(ro));
5323         switch (af) {
5324         case AF_INET:
5325                 dst = satosin(&ro.ro_dst);
5326                 dst->sin_family = AF_INET;
5327                 dst->sin_len = sizeof(*dst);
5328                 dst->sin_addr = addr->v4;
5329                 break;
5330 #ifdef INET6
5331         case AF_INET6:
5332                 /*
5333                  * Skip check for addresses with embedded interface scope,
5334                  * as they would always match anyway.
5335                  */
5336                 if (IN6_IS_SCOPE_EMBED(&addr->v6))
5337                         goto out;
5338                 dst6 = (struct sockaddr_in6 *)&ro.ro_dst;
5339                 dst6->sin6_family = AF_INET6;
5340                 dst6->sin6_len = sizeof(*dst6);
5341                 dst6->sin6_addr = addr->v6;
5342                 break;
5343 #endif /* INET6 */
5344         default:
5345                 return (0);
5346         }
5347
5348         /* Skip checks for ipsec interfaces */
5349         if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5350                 goto out;
5351
5352         switch (af) {
5353 #ifdef INET6
5354         case AF_INET6:
5355                 in6_rtalloc_ign(&ro, 0, rtableid);
5356                 break;
5357 #endif
5358 #ifdef INET
5359         case AF_INET:
5360                 in_rtalloc_ign((struct route *)&ro, 0, rtableid);
5361                 break;
5362 #endif
5363         }
5364
5365         if (ro.ro_rt != NULL) {
5366                 /* No interface given, this is a no-route check */
5367                 if (kif == NULL)
5368                         goto out;
5369
5370                 if (kif->pfik_ifp == NULL) {
5371                         ret = 0;
5372                         goto out;
5373                 }
5374
5375                 /* Perform uRPF check if passed input interface */
5376                 ret = 0;
5377                 rn = (struct radix_node *)ro.ro_rt;
5378                 do {
5379                         rt = (struct rtentry *)rn;
5380                         ifp = rt->rt_ifp;
5381
5382                         if (kif->pfik_ifp == ifp)
5383                                 ret = 1;
5384                         rn = rn_mpath_next(rn);
5385                 } while (check_mpath == 1 && rn != NULL && ret == 0);
5386         } else
5387                 ret = 0;
5388 out:
5389         if (ro.ro_rt != NULL)
5390                 RTFREE(ro.ro_rt);
5391         return (ret);
5392 }
5393 #endif
5394
5395 int
5396 pf_routable(struct pf_addr *addr, sa_family_t af, struct pfi_kif *kif,
5397     int rtableid)
5398 {
5399 #ifdef INET
5400         struct nhop4_basic      nh4;
5401 #endif
5402 #ifdef INET6
5403         struct nhop6_basic      nh6;
5404 #endif
5405         struct ifnet            *ifp;
5406 #ifdef RADIX_MPATH
5407         struct radix_node_head  *rnh;
5408
5409         /* XXX: stick to table 0 for now */
5410         rnh = rt_tables_get_rnh(0, af);
5411         if (rnh != NULL && rn_mpath_capable(rnh))
5412                 return (pf_routable_oldmpath(addr, af, kif, rtableid));
5413 #endif
5414         /*
5415          * Skip check for addresses with embedded interface scope,
5416          * as they would always match anyway.
5417          */
5418         if (af == AF_INET6 && IN6_IS_SCOPE_EMBED(&addr->v6))
5419                 return (1);
5420
5421         if (af != AF_INET && af != AF_INET6)
5422                 return (0);
5423
5424         /* Skip checks for ipsec interfaces */
5425         if (kif != NULL && kif->pfik_ifp->if_type == IFT_ENC)
5426                 return (1);
5427
5428         ifp = NULL;
5429
5430         switch (af) {
5431 #ifdef INET6
5432         case AF_INET6:
5433                 if (fib6_lookup_nh_basic(rtableid, &addr->v6, 0, 0, 0, &nh6)!=0)
5434                         return (0);
5435                 ifp = nh6.nh_ifp;
5436                 break;
5437 #endif
5438 #ifdef INET
5439         case AF_INET:
5440                 if (fib4_lookup_nh_basic(rtableid, addr->v4, 0, 0, &nh4) != 0)
5441                         return (0);
5442                 ifp = nh4.nh_ifp;
5443                 break;
5444 #endif
5445         }
5446
5447         /* No interface given, this is a no-route check */
5448         if (kif == NULL)
5449                 return (1);
5450
5451         if (kif->pfik_ifp == NULL)
5452                 return (0);
5453
5454         /* Perform uRPF check if passed input interface */
5455         if (kif->pfik_ifp == ifp)
5456                 return (1);
5457         return (0);
5458 }
5459
5460 #ifdef INET
5461 static void
5462 pf_route(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5463     struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5464 {
5465         struct mbuf             *m0, *m1;
5466         struct sockaddr_in      dst;
5467         struct ip               *ip;
5468         struct ifnet            *ifp = NULL;
5469         struct pf_addr           naddr;
5470         struct pf_src_node      *sn = NULL;
5471         int                      error = 0;
5472         uint16_t                 ip_len, ip_off;
5473
5474         KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5475         KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5476             __func__));
5477
5478         if ((pd->pf_mtag == NULL &&
5479             ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5480             pd->pf_mtag->routed++ > 3) {
5481                 m0 = *m;
5482                 *m = NULL;
5483                 goto bad_locked;
5484         }
5485
5486         if (r->rt == PF_DUPTO) {
5487                 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5488                         if (s)
5489                                 PF_STATE_UNLOCK(s);
5490                         return;
5491                 }
5492         } else {
5493                 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5494                         if (s)
5495                                 PF_STATE_UNLOCK(s);
5496                         return;
5497                 }
5498                 m0 = *m;
5499         }
5500
5501         ip = mtod(m0, struct ip *);
5502
5503         bzero(&dst, sizeof(dst));
5504         dst.sin_family = AF_INET;
5505         dst.sin_len = sizeof(dst);
5506         dst.sin_addr = ip->ip_dst;
5507
5508         if (TAILQ_EMPTY(&r->rpool.list)) {
5509                 DPFPRINTF(PF_DEBUG_URGENT,
5510                     ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5511                 goto bad_locked;
5512         }
5513         if (s == NULL) {
5514                 pf_map_addr(AF_INET, r, (struct pf_addr *)&ip->ip_src,
5515                     &naddr, NULL, &sn);
5516                 if (!PF_AZERO(&naddr, AF_INET))
5517                         dst.sin_addr.s_addr = naddr.v4.s_addr;
5518                 ifp = r->rpool.cur->kif ?
5519                     r->rpool.cur->kif->pfik_ifp : NULL;
5520         } else {
5521                 if (!PF_AZERO(&s->rt_addr, AF_INET))
5522                         dst.sin_addr.s_addr =
5523                             s->rt_addr.v4.s_addr;
5524                 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5525                 PF_STATE_UNLOCK(s);
5526         }
5527         if (ifp == NULL)
5528                 goto bad;
5529
5530         if (oifp != ifp) {
5531                 if (pf_test(PF_OUT, 0, ifp, &m0, inp) != PF_PASS)
5532                         goto bad;
5533                 else if (m0 == NULL)
5534                         goto done;
5535                 if (m0->m_len < sizeof(struct ip)) {
5536                         DPFPRINTF(PF_DEBUG_URGENT,
5537                             ("%s: m0->m_len < sizeof(struct ip)\n", __func__));
5538                         goto bad;
5539                 }
5540                 ip = mtod(m0, struct ip *);
5541         }
5542
5543         if (ifp->if_flags & IFF_LOOPBACK)
5544                 m0->m_flags |= M_SKIP_FIREWALL;
5545
5546         ip_len = ntohs(ip->ip_len);
5547         ip_off = ntohs(ip->ip_off);
5548
5549         /* Copied from FreeBSD 10.0-CURRENT ip_output. */
5550         m0->m_pkthdr.csum_flags |= CSUM_IP;
5551         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA & ~ifp->if_hwassist) {
5552                 in_delayed_cksum(m0);
5553                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
5554         }
5555 #ifdef SCTP
5556         if (m0->m_pkthdr.csum_flags & CSUM_SCTP & ~ifp->if_hwassist) {
5557                 sctp_delayed_cksum(m, (uint32_t)(ip->ip_hl << 2));
5558                 m0->m_pkthdr.csum_flags &= ~CSUM_SCTP;
5559         }
5560 #endif
5561
5562         /*
5563          * If small enough for interface, or the interface will take
5564          * care of the fragmentation for us, we can just send directly.
5565          */
5566         if (ip_len <= ifp->if_mtu ||
5567             (m0->m_pkthdr.csum_flags & ifp->if_hwassist & CSUM_TSO) != 0) {
5568                 ip->ip_sum = 0;
5569                 if (m0->m_pkthdr.csum_flags & CSUM_IP & ~ifp->if_hwassist) {
5570                         ip->ip_sum = in_cksum(m0, ip->ip_hl << 2);
5571                         m0->m_pkthdr.csum_flags &= ~CSUM_IP;
5572                 }
5573                 m_clrprotoflags(m0);    /* Avoid confusing lower layers. */
5574                 error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5575                 goto done;
5576         }
5577
5578         /* Balk when DF bit is set or the interface didn't support TSO. */
5579         if ((ip_off & IP_DF) || (m0->m_pkthdr.csum_flags & CSUM_TSO)) {
5580                 error = EMSGSIZE;
5581                 KMOD_IPSTAT_INC(ips_cantfrag);
5582                 if (r->rt != PF_DUPTO) {
5583                         icmp_error(m0, ICMP_UNREACH, ICMP_UNREACH_NEEDFRAG, 0,
5584                             ifp->if_mtu);
5585                         goto done;
5586                 } else
5587                         goto bad;
5588         }
5589
5590         error = ip_fragment(ip, &m0, ifp->if_mtu, ifp->if_hwassist);
5591         if (error)
5592                 goto bad;
5593
5594         for (; m0; m0 = m1) {
5595                 m1 = m0->m_nextpkt;
5596                 m0->m_nextpkt = NULL;
5597                 if (error == 0) {
5598                         m_clrprotoflags(m0);
5599                         error = (*ifp->if_output)(ifp, m0, sintosa(&dst), NULL);
5600                 } else
5601                         m_freem(m0);
5602         }
5603
5604         if (error == 0)
5605                 KMOD_IPSTAT_INC(ips_fragmented);
5606
5607 done:
5608         if (r->rt != PF_DUPTO)
5609                 *m = NULL;
5610         return;
5611
5612 bad_locked:
5613         if (s)
5614                 PF_STATE_UNLOCK(s);
5615 bad:
5616         m_freem(m0);
5617         goto done;
5618 }
5619 #endif /* INET */
5620
5621 #ifdef INET6
5622 static void
5623 pf_route6(struct mbuf **m, struct pf_rule *r, int dir, struct ifnet *oifp,
5624     struct pf_state *s, struct pf_pdesc *pd, struct inpcb *inp)
5625 {
5626         struct mbuf             *m0;
5627         struct sockaddr_in6     dst;
5628         struct ip6_hdr          *ip6;
5629         struct ifnet            *ifp = NULL;
5630         struct pf_addr           naddr;
5631         struct pf_src_node      *sn = NULL;
5632
5633         KASSERT(m && *m && r && oifp, ("%s: invalid parameters", __func__));
5634         KASSERT(dir == PF_IN || dir == PF_OUT, ("%s: invalid direction",
5635             __func__));
5636
5637         if ((pd->pf_mtag == NULL &&
5638             ((pd->pf_mtag = pf_get_mtag(*m)) == NULL)) ||
5639             pd->pf_mtag->routed++ > 3) {
5640                 m0 = *m;
5641                 *m = NULL;
5642                 goto bad_locked;
5643         }
5644
5645         if (r->rt == PF_DUPTO) {
5646                 if ((m0 = m_dup(*m, M_NOWAIT)) == NULL) {
5647                         if (s)
5648                                 PF_STATE_UNLOCK(s);
5649                         return;
5650                 }
5651         } else {
5652                 if ((r->rt == PF_REPLYTO) == (r->direction == dir)) {
5653                         if (s)
5654                                 PF_STATE_UNLOCK(s);
5655                         return;
5656                 }
5657                 m0 = *m;
5658         }
5659
5660         ip6 = mtod(m0, struct ip6_hdr *);
5661
5662         bzero(&dst, sizeof(dst));
5663         dst.sin6_family = AF_INET6;
5664         dst.sin6_len = sizeof(dst);
5665         dst.sin6_addr = ip6->ip6_dst;
5666
5667         if (TAILQ_EMPTY(&r->rpool.list)) {
5668                 DPFPRINTF(PF_DEBUG_URGENT,
5669                     ("%s: TAILQ_EMPTY(&r->rpool.list)\n", __func__));
5670                 goto bad_locked;
5671         }
5672         if (s == NULL) {
5673                 pf_map_addr(AF_INET6, r, (struct pf_addr *)&ip6->ip6_src,
5674                     &naddr, NULL, &sn);
5675                 if (!PF_AZERO(&naddr, AF_INET6))
5676                         PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5677                             &naddr, AF_INET6);
5678                 ifp = r->rpool.cur->kif ? r->rpool.cur->kif->pfik_ifp : NULL;
5679         } else {
5680                 if (!PF_AZERO(&s->rt_addr, AF_INET6))
5681                         PF_ACPY((struct pf_addr *)&dst.sin6_addr,
5682                             &s->rt_addr, AF_INET6);
5683                 ifp = s->rt_kif ? s->rt_kif->pfik_ifp : NULL;
5684         }
5685
5686         if (s)
5687                 PF_STATE_UNLOCK(s);
5688
5689         if (ifp == NULL)
5690                 goto bad;
5691
5692         if (oifp != ifp) {
5693                 if (pf_test6(PF_OUT, PFIL_FWD, ifp, &m0, inp) != PF_PASS)
5694                         goto bad;
5695                 else if (m0 == NULL)
5696                         goto done;
5697                 if (m0->m_len < sizeof(struct ip6_hdr)) {
5698                         DPFPRINTF(PF_DEBUG_URGENT,
5699                             ("%s: m0->m_len < sizeof(struct ip6_hdr)\n",
5700                             __func__));
5701                         goto bad;
5702                 }
5703                 ip6 = mtod(m0, struct ip6_hdr *);
5704         }
5705
5706         if (ifp->if_flags & IFF_LOOPBACK)
5707                 m0->m_flags |= M_SKIP_FIREWALL;
5708
5709         if (m0->m_pkthdr.csum_flags & CSUM_DELAY_DATA_IPV6 &
5710             ~ifp->if_hwassist) {
5711                 uint32_t plen = m0->m_pkthdr.len - sizeof(*ip6);
5712                 in6_delayed_cksum(m0, plen, sizeof(struct ip6_hdr));
5713                 m0->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA_IPV6;
5714         }
5715
5716         /*
5717          * If the packet is too large for the outgoing interface,
5718          * send back an icmp6 error.
5719          */
5720         if (IN6_IS_SCOPE_EMBED(&dst.sin6_addr))
5721                 dst.sin6_addr.s6_addr16[1] = htons(ifp->if_index);
5722         if ((u_long)m0->m_pkthdr.len <= ifp->if_mtu)
5723                 nd6_output_ifp(ifp, ifp, m0, &dst, NULL);
5724         else {
5725                 in6_ifstat_inc(ifp, ifs6_in_toobig);
5726                 if (r->rt != PF_DUPTO)
5727                         icmp6_error(m0, ICMP6_PACKET_TOO_BIG, 0, ifp->if_mtu);
5728                 else
5729                         goto bad;
5730         }
5731
5732 done:
5733         if (r->rt != PF_DUPTO)
5734                 *m = NULL;
5735         return;
5736
5737 bad_locked:
5738         if (s)
5739                 PF_STATE_UNLOCK(s);
5740 bad:
5741         m_freem(m0);
5742         goto done;
5743 }
5744 #endif /* INET6 */
5745
5746 /*
5747  * FreeBSD supports cksum offloads for the following drivers.
5748  *  em(4), fxp(4), lge(4), ndis(4), nge(4), re(4), ti(4), txp(4), xl(4)
5749  *
5750  * CSUM_DATA_VALID | CSUM_PSEUDO_HDR :
5751  *  network driver performed cksum including pseudo header, need to verify
5752  *   csum_data
5753  * CSUM_DATA_VALID :
5754  *  network driver performed cksum, needs to additional pseudo header
5755  *  cksum computation with partial csum_data(i.e. lack of H/W support for
5756  *  pseudo header, for instance hme(4), sk(4) and possibly gem(4))
5757  *
5758  * After validating the cksum of packet, set both flag CSUM_DATA_VALID and
5759  * CSUM_PSEUDO_HDR in order to avoid recomputation of the cksum in upper
5760  * TCP/UDP layer.
5761  * Also, set csum_data to 0xffff to force cksum validation.
5762  */
5763 static int
5764 pf_check_proto_cksum(struct mbuf *m, int off, int len, u_int8_t p, sa_family_t af)
5765 {
5766         u_int16_t sum = 0;
5767         int hw_assist = 0;
5768         struct ip *ip;
5769
5770         if (off < sizeof(struct ip) || len < sizeof(struct udphdr))
5771                 return (1);
5772         if (m->m_pkthdr.len < off + len)
5773                 return (1);
5774
5775         switch (p) {
5776         case IPPROTO_TCP:
5777                 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5778                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5779                                 sum = m->m_pkthdr.csum_data;
5780                         } else {
5781                                 ip = mtod(m, struct ip *);
5782                                 sum = in_pseudo(ip->ip_src.s_addr,
5783                                 ip->ip_dst.s_addr, htonl((u_short)len +
5784                                 m->m_pkthdr.csum_data + IPPROTO_TCP));
5785                         }
5786                         sum ^= 0xffff;
5787                         ++hw_assist;
5788                 }
5789                 break;
5790         case IPPROTO_UDP:
5791                 if (m->m_pkthdr.csum_flags & CSUM_DATA_VALID) {
5792                         if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) {
5793                                 sum = m->m_pkthdr.csum_data;
5794                         } else {
5795                                 ip = mtod(m, struct ip *);
5796                                 sum = in_pseudo(ip->ip_src.s_addr,
5797                                 ip->ip_dst.s_addr, htonl((u_short)len +
5798                                 m->m_pkthdr.csum_data + IPPROTO_UDP));
5799                         }
5800                         sum ^= 0xffff;
5801                         ++hw_assist;
5802                 }
5803                 break;
5804         case IPPROTO_ICMP:
5805 #ifdef INET6
5806         case IPPROTO_ICMPV6:
5807 #endif /* INET6 */
5808                 break;
5809         default:
5810                 return (1);
5811         }
5812
5813         if (!hw_assist) {
5814                 switch (af) {
5815                 case AF_INET:
5816                         if (p == IPPROTO_ICMP) {
5817                                 if (m->m_len < off)
5818                                         return (1);
5819                                 m->m_data += off;
5820                                 m->m_len -= off;
5821                                 sum = in_cksum(m, len);
5822                                 m->m_data -= off;
5823                                 m->m_len += off;
5824                         } else {
5825                                 if (m->m_len < sizeof(struct ip))
5826                                         return (1);
5827                                 sum = in4_cksum(m, p, off, len);
5828                         }
5829                         break;
5830 #ifdef INET6
5831                 case AF_INET6:
5832                         if (m->m_len < sizeof(struct ip6_hdr))
5833                                 return (1);
5834                         sum = in6_cksum(m, p, off, len);
5835                         break;
5836 #endif /* INET6 */
5837                 default:
5838                         return (1);
5839                 }
5840         }
5841         if (sum) {
5842                 switch (p) {
5843                 case IPPROTO_TCP:
5844                     {
5845                         KMOD_TCPSTAT_INC(tcps_rcvbadsum);
5846                         break;
5847                     }
5848                 case IPPROTO_UDP:
5849                     {
5850                         KMOD_UDPSTAT_INC(udps_badsum);
5851                         break;
5852                     }
5853 #ifdef INET
5854                 case IPPROTO_ICMP:
5855                     {
5856                         KMOD_ICMPSTAT_INC(icps_checksum);
5857                         break;
5858                     }
5859 #endif
5860 #ifdef INET6
5861                 case IPPROTO_ICMPV6:
5862                     {
5863                         KMOD_ICMP6STAT_INC(icp6s_checksum);
5864                         break;
5865                     }
5866 #endif /* INET6 */
5867                 }
5868                 return (1);
5869         } else {
5870                 if (p == IPPROTO_TCP || p == IPPROTO_UDP) {
5871                         m->m_pkthdr.csum_flags |=
5872                             (CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
5873                         m->m_pkthdr.csum_data = 0xffff;
5874                 }
5875         }
5876         return (0);
5877 }
5878
5879
5880 #ifdef INET
5881 int
5882 pf_test(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
5883 {
5884         struct pfi_kif          *kif;
5885         u_short                  action, reason = 0, log = 0;
5886         struct mbuf             *m = *m0;
5887         struct ip               *h = NULL;
5888         struct m_tag            *ipfwtag;
5889         struct pf_rule          *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
5890         struct pf_state         *s = NULL;
5891         struct pf_ruleset       *ruleset = NULL;
5892         struct pf_pdesc          pd;
5893         int                      off, dirndx, pqid = 0;
5894
5895         PF_RULES_RLOCK_TRACKER;
5896
5897         M_ASSERTPKTHDR(m);
5898
5899         if (!V_pf_status.running)
5900                 return (PF_PASS);
5901
5902         memset(&pd, 0, sizeof(pd));
5903
5904         kif = (struct pfi_kif *)ifp->if_pf_kif;
5905
5906         if (kif == NULL) {
5907                 DPFPRINTF(PF_DEBUG_URGENT,
5908                     ("pf_test: kif == NULL, if_xname %s\n", ifp->if_xname));
5909                 return (PF_DROP);
5910         }
5911         if (kif->pfik_flags & PFI_IFLAG_SKIP)
5912                 return (PF_PASS);
5913
5914         if (m->m_flags & M_SKIP_FIREWALL)
5915                 return (PF_PASS);
5916
5917         pd.pf_mtag = pf_find_mtag(m);
5918
5919         PF_RULES_RLOCK();
5920
5921         if (ip_divert_ptr != NULL &&
5922             ((ipfwtag = m_tag_locate(m, MTAG_IPFW_RULE, 0, NULL)) != NULL)) {
5923                 struct ipfw_rule_ref *rr = (struct ipfw_rule_ref *)(ipfwtag+1);
5924                 if (rr->info & IPFW_IS_DIVERT && rr->rulenum == 0) {
5925                         if (pd.pf_mtag == NULL &&
5926                             ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
5927                                 action = PF_DROP;
5928                                 goto done;
5929                         }
5930                         pd.pf_mtag->flags |= PF_PACKET_LOOPED;
5931                         m_tag_delete(m, ipfwtag);
5932                 }
5933                 if (pd.pf_mtag && pd.pf_mtag->flags & PF_FASTFWD_OURS_PRESENT) {
5934                         m->m_flags |= M_FASTFWD_OURS;
5935                         pd.pf_mtag->flags &= ~PF_FASTFWD_OURS_PRESENT;
5936                 }
5937         } else if (pf_normalize_ip(m0, dir, kif, &reason, &pd) != PF_PASS) {
5938                 /* We do IP header normalization and packet reassembly here */
5939                 action = PF_DROP;
5940                 goto done;
5941         }
5942         m = *m0;        /* pf_normalize messes with m0 */
5943         h = mtod(m, struct ip *);
5944
5945         off = h->ip_hl << 2;
5946         if (off < (int)sizeof(struct ip)) {
5947                 action = PF_DROP;
5948                 REASON_SET(&reason, PFRES_SHORT);
5949                 log = 1;
5950                 goto done;
5951         }
5952
5953         pd.src = (struct pf_addr *)&h->ip_src;
5954         pd.dst = (struct pf_addr *)&h->ip_dst;
5955         pd.sport = pd.dport = NULL;
5956         pd.ip_sum = &h->ip_sum;
5957         pd.proto_sum = NULL;
5958         pd.proto = h->ip_p;
5959         pd.dir = dir;
5960         pd.sidx = (dir == PF_IN) ? 0 : 1;
5961         pd.didx = (dir == PF_IN) ? 1 : 0;
5962         pd.af = AF_INET;
5963         pd.tos = h->ip_tos & ~IPTOS_ECN_MASK;
5964         pd.tot_len = ntohs(h->ip_len);
5965
5966         /* handle fragments that didn't get reassembled by normalization */
5967         if (h->ip_off & htons(IP_MF | IP_OFFMASK)) {
5968                 action = pf_test_fragment(&r, dir, kif, m, h,
5969                     &pd, &a, &ruleset);
5970                 goto done;
5971         }
5972
5973         switch (h->ip_p) {
5974
5975         case IPPROTO_TCP: {
5976                 struct tcphdr   th;
5977
5978                 pd.hdr.tcp = &th;
5979                 if (!pf_pull_hdr(m, off, &th, sizeof(th),
5980                     &action, &reason, AF_INET)) {
5981                         log = action != PF_PASS;
5982                         goto done;
5983                 }
5984                 pd.p_len = pd.tot_len - off - (th.th_off << 2);
5985                 if ((th.th_flags & TH_ACK) && pd.p_len == 0)
5986                         pqid = 1;
5987                 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
5988                 if (action == PF_DROP)
5989                         goto done;
5990                 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
5991                     &reason);
5992                 if (action == PF_PASS) {
5993                         if (pfsync_update_state_ptr != NULL)
5994                                 pfsync_update_state_ptr(s);
5995                         r = s->rule.ptr;
5996                         a = s->anchor.ptr;
5997                         log = s->log;
5998                 } else if (s == NULL)
5999                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6000                             &a, &ruleset, inp);
6001                 break;
6002         }
6003
6004         case IPPROTO_UDP: {
6005                 struct udphdr   uh;
6006
6007                 pd.hdr.udp = &uh;
6008                 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6009                     &action, &reason, AF_INET)) {
6010                         log = action != PF_PASS;
6011                         goto done;
6012                 }
6013                 if (uh.uh_dport == 0 ||
6014                     ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6015                     ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6016                         action = PF_DROP;
6017                         REASON_SET(&reason, PFRES_SHORT);
6018                         goto done;
6019                 }
6020                 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6021                 if (action == PF_PASS) {
6022                         if (pfsync_update_state_ptr != NULL)
6023                                 pfsync_update_state_ptr(s);
6024                         r = s->rule.ptr;
6025                         a = s->anchor.ptr;
6026                         log = s->log;
6027                 } else if (s == NULL)
6028                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6029                             &a, &ruleset, inp);
6030                 break;
6031         }
6032
6033         case IPPROTO_ICMP: {
6034                 struct icmp     ih;
6035
6036                 pd.hdr.icmp = &ih;
6037                 if (!pf_pull_hdr(m, off, &ih, ICMP_MINLEN,
6038                     &action, &reason, AF_INET)) {
6039                         log = action != PF_PASS;
6040                         goto done;
6041                 }
6042                 action = pf_test_state_icmp(&s, dir, kif, m, off, h, &pd,
6043                     &reason);
6044                 if (action == PF_PASS) {
6045                         if (pfsync_update_state_ptr != NULL)
6046                                 pfsync_update_state_ptr(s);
6047                         r = s->rule.ptr;
6048                         a = s->anchor.ptr;
6049                         log = s->log;
6050                 } else if (s == NULL)
6051                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6052                             &a, &ruleset, inp);
6053                 break;
6054         }
6055
6056 #ifdef INET6
6057         case IPPROTO_ICMPV6: {
6058                 action = PF_DROP;
6059                 DPFPRINTF(PF_DEBUG_MISC,
6060                     ("pf: dropping IPv4 packet with ICMPv6 payload\n"));
6061                 goto done;
6062         }
6063 #endif
6064
6065         default:
6066                 action = pf_test_state_other(&s, dir, kif, m, &pd);
6067                 if (action == PF_PASS) {
6068                         if (pfsync_update_state_ptr != NULL)
6069                                 pfsync_update_state_ptr(s);
6070                         r = s->rule.ptr;
6071                         a = s->anchor.ptr;
6072                         log = s->log;
6073                 } else if (s == NULL)
6074                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6075                             &a, &ruleset, inp);
6076                 break;
6077         }
6078
6079 done:
6080         PF_RULES_RUNLOCK();
6081         if (action == PF_PASS && h->ip_hl > 5 &&
6082             !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6083                 action = PF_DROP;
6084                 REASON_SET(&reason, PFRES_IPOPTIONS);
6085                 log = r->log;
6086                 DPFPRINTF(PF_DEBUG_MISC,
6087                     ("pf: dropping packet with ip options\n"));
6088         }
6089
6090         if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6091                 action = PF_DROP;
6092                 REASON_SET(&reason, PFRES_MEMORY);
6093         }
6094         if (r->rtableid >= 0)
6095                 M_SETFIB(m, r->rtableid);
6096
6097         if (r->scrub_flags & PFSTATE_SETPRIO) {
6098                 if (pd.tos & IPTOS_LOWDELAY)
6099                         pqid = 1;
6100                 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6101                         action = PF_DROP;
6102                         REASON_SET(&reason, PFRES_MEMORY);
6103                         log = 1;
6104                         DPFPRINTF(PF_DEBUG_MISC,
6105                             ("pf: failed to allocate 802.1q mtag\n"));
6106                 }
6107         }
6108
6109 #ifdef ALTQ
6110         if (action == PF_PASS && r->qid) {
6111                 if (pd.pf_mtag == NULL &&
6112                     ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6113                         action = PF_DROP;
6114                         REASON_SET(&reason, PFRES_MEMORY);
6115                 } else {
6116                         if (s != NULL)
6117                                 pd.pf_mtag->qid_hash = pf_state_hash(s);
6118                         if (pqid || (pd.tos & IPTOS_LOWDELAY))
6119                                 pd.pf_mtag->qid = r->pqid;
6120                         else
6121                                 pd.pf_mtag->qid = r->qid;
6122                         /* Add hints for ecn. */
6123                         pd.pf_mtag->hdr = h;
6124                 }
6125
6126         }
6127 #endif /* ALTQ */
6128
6129         /*
6130          * connections redirected to loopback should not match sockets
6131          * bound specifically to loopback due to security implications,
6132          * see tcp_input() and in_pcblookup_listen().
6133          */
6134         if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6135             pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6136             (s->nat_rule.ptr->action == PF_RDR ||
6137             s->nat_rule.ptr->action == PF_BINAT) &&
6138             (ntohl(pd.dst->v4.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET)
6139                 m->m_flags |= M_SKIP_FIREWALL;
6140
6141         if (action == PF_PASS && r->divert.port && ip_divert_ptr != NULL &&
6142             !PACKET_LOOPED(&pd)) {
6143
6144                 ipfwtag = m_tag_alloc(MTAG_IPFW_RULE, 0,
6145                     sizeof(struct ipfw_rule_ref), M_NOWAIT | M_ZERO);
6146                 if (ipfwtag != NULL) {
6147                         ((struct ipfw_rule_ref *)(ipfwtag+1))->info =
6148                             ntohs(r->divert.port);
6149                         ((struct ipfw_rule_ref *)(ipfwtag+1))->rulenum = dir;
6150
6151                         if (s)
6152                                 PF_STATE_UNLOCK(s);
6153
6154                         m_tag_prepend(m, ipfwtag);
6155                         if (m->m_flags & M_FASTFWD_OURS) {
6156                                 if (pd.pf_mtag == NULL &&
6157                                     ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6158                                         action = PF_DROP;
6159                                         REASON_SET(&reason, PFRES_MEMORY);
6160                                         log = 1;
6161                                         DPFPRINTF(PF_DEBUG_MISC,
6162                                             ("pf: failed to allocate tag\n"));
6163                                 } else {
6164                                         pd.pf_mtag->flags |=
6165                                             PF_FASTFWD_OURS_PRESENT;
6166                                         m->m_flags &= ~M_FASTFWD_OURS;
6167                                 }
6168                         }
6169                         ip_divert_ptr(*m0, dir ==  PF_IN ? DIR_IN : DIR_OUT);
6170                         *m0 = NULL;
6171
6172                         return (action);
6173                 } else {
6174                         /* XXX: ipfw has the same behaviour! */
6175                         action = PF_DROP;
6176                         REASON_SET(&reason, PFRES_MEMORY);
6177                         log = 1;
6178                         DPFPRINTF(PF_DEBUG_MISC,
6179                             ("pf: failed to allocate divert tag\n"));
6180                 }
6181         }
6182
6183         if (log) {
6184                 struct pf_rule *lr;
6185
6186                 if (s != NULL && s->nat_rule.ptr != NULL &&
6187                     s->nat_rule.ptr->log & PF_LOG_ALL)
6188                         lr = s->nat_rule.ptr;
6189                 else
6190                         lr = r;
6191                 PFLOG_PACKET(kif, m, AF_INET, dir, reason, lr, a, ruleset, &pd,
6192                     (s == NULL));
6193         }
6194
6195         kif->pfik_bytes[0][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6196         kif->pfik_packets[0][dir == PF_OUT][action != PF_PASS]++;
6197
6198         if (action == PF_PASS || r->action == PF_DROP) {
6199                 dirndx = (dir == PF_OUT);
6200                 r->packets[dirndx]++;
6201                 r->bytes[dirndx] += pd.tot_len;
6202                 if (a != NULL) {
6203                         a->packets[dirndx]++;
6204                         a->bytes[dirndx] += pd.tot_len;
6205                 }
6206                 if (s != NULL) {
6207                         if (s->nat_rule.ptr != NULL) {
6208                                 s->nat_rule.ptr->packets[dirndx]++;
6209                                 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6210                         }
6211                         if (s->src_node != NULL) {
6212                                 s->src_node->packets[dirndx]++;
6213                                 s->src_node->bytes[dirndx] += pd.tot_len;
6214                         }
6215                         if (s->nat_src_node != NULL) {
6216                                 s->nat_src_node->packets[dirndx]++;
6217                                 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6218                         }
6219                         dirndx = (dir == s->direction) ? 0 : 1;
6220                         s->packets[dirndx]++;
6221                         s->bytes[dirndx] += pd.tot_len;
6222                 }
6223                 tr = r;
6224                 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6225                 if (nr != NULL && r == &V_pf_default_rule)
6226                         tr = nr;
6227                 if (tr->src.addr.type == PF_ADDR_TABLE)
6228                         pfr_update_stats(tr->src.addr.p.tbl,
6229                             (s == NULL) ? pd.src :
6230                             &s->key[(s->direction == PF_IN)]->
6231                                 addr[(s->direction == PF_OUT)],
6232                             pd.af, pd.tot_len, dir == PF_OUT,
6233                             r->action == PF_PASS, tr->src.neg);
6234                 if (tr->dst.addr.type == PF_ADDR_TABLE)
6235                         pfr_update_stats(tr->dst.addr.p.tbl,
6236                             (s == NULL) ? pd.dst :
6237                             &s->key[(s->direction == PF_IN)]->
6238                                 addr[(s->direction == PF_IN)],
6239                             pd.af, pd.tot_len, dir == PF_OUT,
6240                             r->action == PF_PASS, tr->dst.neg);
6241         }
6242
6243         switch (action) {
6244         case PF_SYNPROXY_DROP:
6245                 m_freem(*m0);
6246         case PF_DEFER:
6247                 *m0 = NULL;
6248                 action = PF_PASS;
6249                 break;
6250         case PF_DROP:
6251                 m_freem(*m0);
6252                 *m0 = NULL;
6253                 break;
6254         default:
6255                 /* pf_route() returns unlocked. */
6256                 if (r->rt) {
6257                         pf_route(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6258                         return (action);
6259                 }
6260                 break;
6261         }
6262         if (s)
6263                 PF_STATE_UNLOCK(s);
6264
6265         return (action);
6266 }
6267 #endif /* INET */
6268
6269 #ifdef INET6
6270 int
6271 pf_test6(int dir, int pflags, struct ifnet *ifp, struct mbuf **m0, struct inpcb *inp)
6272 {
6273         struct pfi_kif          *kif;
6274         u_short                  action, reason = 0, log = 0;
6275         struct mbuf             *m = *m0, *n = NULL;
6276         struct m_tag            *mtag;
6277         struct ip6_hdr          *h = NULL;
6278         struct pf_rule          *a = NULL, *r = &V_pf_default_rule, *tr, *nr;
6279         struct pf_state         *s = NULL;
6280         struct pf_ruleset       *ruleset = NULL;
6281         struct pf_pdesc          pd;
6282         int                      off, terminal = 0, dirndx, rh_cnt = 0, pqid = 0;
6283
6284         PF_RULES_RLOCK_TRACKER;
6285         M_ASSERTPKTHDR(m);
6286
6287         if (!V_pf_status.running)
6288                 return (PF_PASS);
6289
6290         memset(&pd, 0, sizeof(pd));
6291         pd.pf_mtag = pf_find_mtag(m);
6292
6293         if (pd.pf_mtag && pd.pf_mtag->flags & PF_TAG_GENERATED)
6294                 return (PF_PASS);
6295
6296         kif = (struct pfi_kif *)ifp->if_pf_kif;
6297         if (kif == NULL) {
6298                 DPFPRINTF(PF_DEBUG_URGENT,
6299                     ("pf_test6: kif == NULL, if_xname %s\n", ifp->if_xname));
6300                 return (PF_DROP);
6301         }
6302         if (kif->pfik_flags & PFI_IFLAG_SKIP)
6303                 return (PF_PASS);
6304
6305         if (m->m_flags & M_SKIP_FIREWALL)
6306                 return (PF_PASS);
6307
6308         PF_RULES_RLOCK();
6309
6310         /* We do IP header normalization and packet reassembly here */
6311         if (pf_normalize_ip6(m0, dir, kif, &reason, &pd) != PF_PASS) {
6312                 action = PF_DROP;
6313                 goto done;
6314         }
6315         m = *m0;        /* pf_normalize messes with m0 */
6316         h = mtod(m, struct ip6_hdr *);
6317
6318 #if 1
6319         /*
6320          * we do not support jumbogram yet.  if we keep going, zero ip6_plen
6321          * will do something bad, so drop the packet for now.
6322          */
6323         if (htons(h->ip6_plen) == 0) {
6324                 action = PF_DROP;
6325                 REASON_SET(&reason, PFRES_NORM);        /*XXX*/
6326                 goto done;
6327         }
6328 #endif
6329
6330         pd.src = (struct pf_addr *)&h->ip6_src;
6331         pd.dst = (struct pf_addr *)&h->ip6_dst;
6332         pd.sport = pd.dport = NULL;
6333         pd.ip_sum = NULL;
6334         pd.proto_sum = NULL;
6335         pd.dir = dir;
6336         pd.sidx = (dir == PF_IN) ? 0 : 1;
6337         pd.didx = (dir == PF_IN) ? 1 : 0;
6338         pd.af = AF_INET6;
6339         pd.tos = 0;
6340         pd.tot_len = ntohs(h->ip6_plen) + sizeof(struct ip6_hdr);
6341
6342         off = ((caddr_t)h - m->m_data) + sizeof(struct ip6_hdr);
6343         pd.proto = h->ip6_nxt;
6344         do {
6345                 switch (pd.proto) {
6346                 case IPPROTO_FRAGMENT:
6347                         action = pf_test_fragment(&r, dir, kif, m, h,
6348                             &pd, &a, &ruleset);
6349                         if (action == PF_DROP)
6350                                 REASON_SET(&reason, PFRES_FRAG);
6351                         goto done;
6352                 case IPPROTO_ROUTING: {
6353                         struct ip6_rthdr rthdr;
6354
6355                         if (rh_cnt++) {
6356                                 DPFPRINTF(PF_DEBUG_MISC,
6357                                     ("pf: IPv6 more than one rthdr\n"));
6358                                 action = PF_DROP;
6359                                 REASON_SET(&reason, PFRES_IPOPTIONS);
6360                                 log = 1;
6361                                 goto done;
6362                         }
6363                         if (!pf_pull_hdr(m, off, &rthdr, sizeof(rthdr), NULL,
6364                             &reason, pd.af)) {
6365                                 DPFPRINTF(PF_DEBUG_MISC,
6366                                     ("pf: IPv6 short rthdr\n"));
6367                                 action = PF_DROP;
6368                                 REASON_SET(&reason, PFRES_SHORT);
6369                                 log = 1;
6370                                 goto done;
6371                         }
6372                         if (rthdr.ip6r_type == IPV6_RTHDR_TYPE_0) {
6373                                 DPFPRINTF(PF_DEBUG_MISC,
6374                                     ("pf: IPv6 rthdr0\n"));
6375                                 action = PF_DROP;
6376                                 REASON_SET(&reason, PFRES_IPOPTIONS);
6377                                 log = 1;
6378                                 goto done;
6379                         }
6380                         /* FALLTHROUGH */
6381                 }
6382                 case IPPROTO_AH:
6383                 case IPPROTO_HOPOPTS:
6384                 case IPPROTO_DSTOPTS: {
6385                         /* get next header and header length */
6386                         struct ip6_ext  opt6;
6387
6388                         if (!pf_pull_hdr(m, off, &opt6, sizeof(opt6),
6389                             NULL, &reason, pd.af)) {
6390                                 DPFPRINTF(PF_DEBUG_MISC,
6391                                     ("pf: IPv6 short opt\n"));
6392                                 action = PF_DROP;
6393                                 log = 1;
6394                                 goto done;
6395                         }
6396                         if (pd.proto == IPPROTO_AH)
6397                                 off += (opt6.ip6e_len + 2) * 4;
6398                         else
6399                                 off += (opt6.ip6e_len + 1) * 8;
6400                         pd.proto = opt6.ip6e_nxt;
6401                         /* goto the next header */
6402                         break;
6403                 }
6404                 default:
6405                         terminal++;
6406                         break;
6407                 }
6408         } while (!terminal);
6409
6410         /* if there's no routing header, use unmodified mbuf for checksumming */
6411         if (!n)
6412                 n = m;
6413
6414         switch (pd.proto) {
6415
6416         case IPPROTO_TCP: {
6417                 struct tcphdr   th;
6418
6419                 pd.hdr.tcp = &th;
6420                 if (!pf_pull_hdr(m, off, &th, sizeof(th),
6421                     &action, &reason, AF_INET6)) {
6422                         log = action != PF_PASS;
6423                         goto done;
6424                 }
6425                 pd.p_len = pd.tot_len - off - (th.th_off << 2);
6426                 action = pf_normalize_tcp(dir, kif, m, 0, off, h, &pd);
6427                 if (action == PF_DROP)
6428                         goto done;
6429                 action = pf_test_state_tcp(&s, dir, kif, m, off, h, &pd,
6430                     &reason);
6431                 if (action == PF_PASS) {
6432                         if (pfsync_update_state_ptr != NULL)
6433                                 pfsync_update_state_ptr(s);
6434                         r = s->rule.ptr;
6435                         a = s->anchor.ptr;
6436                         log = s->log;
6437                 } else if (s == NULL)
6438                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6439                             &a, &ruleset, inp);
6440                 break;
6441         }
6442
6443         case IPPROTO_UDP: {
6444                 struct udphdr   uh;
6445
6446                 pd.hdr.udp = &uh;
6447                 if (!pf_pull_hdr(m, off, &uh, sizeof(uh),
6448                     &action, &reason, AF_INET6)) {
6449                         log = action != PF_PASS;
6450                         goto done;
6451                 }
6452                 if (uh.uh_dport == 0 ||
6453                     ntohs(uh.uh_ulen) > m->m_pkthdr.len - off ||
6454                     ntohs(uh.uh_ulen) < sizeof(struct udphdr)) {
6455                         action = PF_DROP;
6456                         REASON_SET(&reason, PFRES_SHORT);
6457                         goto done;
6458                 }
6459                 action = pf_test_state_udp(&s, dir, kif, m, off, h, &pd);
6460                 if (action == PF_PASS) {
6461                         if (pfsync_update_state_ptr != NULL)
6462                                 pfsync_update_state_ptr(s);
6463                         r = s->rule.ptr;
6464                         a = s->anchor.ptr;
6465                         log = s->log;
6466                 } else if (s == NULL)
6467                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6468                             &a, &ruleset, inp);
6469                 break;
6470         }
6471
6472         case IPPROTO_ICMP: {
6473                 action = PF_DROP;
6474                 DPFPRINTF(PF_DEBUG_MISC,
6475                     ("pf: dropping IPv6 packet with ICMPv4 payload\n"));
6476                 goto done;
6477         }
6478
6479         case IPPROTO_ICMPV6: {
6480                 struct icmp6_hdr        ih;
6481
6482                 pd.hdr.icmp6 = &ih;
6483                 if (!pf_pull_hdr(m, off, &ih, sizeof(ih),
6484                     &action, &reason, AF_INET6)) {
6485                         log = action != PF_PASS;
6486                         goto done;
6487                 }
6488                 action = pf_test_state_icmp(&s, dir, kif,
6489                     m, off, h, &pd, &reason);
6490                 if (action == PF_PASS) {
6491                         if (pfsync_update_state_ptr != NULL)
6492                                 pfsync_update_state_ptr(s);
6493                         r = s->rule.ptr;
6494                         a = s->anchor.ptr;
6495                         log = s->log;
6496                 } else if (s == NULL)
6497                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6498                             &a, &ruleset, inp);
6499                 break;
6500         }
6501
6502         default:
6503                 action = pf_test_state_other(&s, dir, kif, m, &pd);
6504                 if (action == PF_PASS) {
6505                         if (pfsync_update_state_ptr != NULL)
6506                                 pfsync_update_state_ptr(s);
6507                         r = s->rule.ptr;
6508                         a = s->anchor.ptr;
6509                         log = s->log;
6510                 } else if (s == NULL)
6511                         action = pf_test_rule(&r, &s, dir, kif, m, off, &pd,
6512                             &a, &ruleset, inp);
6513                 break;
6514         }
6515
6516 done:
6517         PF_RULES_RUNLOCK();
6518         if (n != m) {
6519                 m_freem(n);
6520                 n = NULL;
6521         }
6522
6523         /* handle dangerous IPv6 extension headers. */
6524         if (action == PF_PASS && rh_cnt &&
6525             !((s && s->state_flags & PFSTATE_ALLOWOPTS) || r->allow_opts)) {
6526                 action = PF_DROP;
6527                 REASON_SET(&reason, PFRES_IPOPTIONS);
6528                 log = r->log;
6529                 DPFPRINTF(PF_DEBUG_MISC,
6530                     ("pf: dropping packet with dangerous v6 headers\n"));
6531         }
6532
6533         if (s && s->tag > 0 && pf_tag_packet(m, &pd, s->tag)) {
6534                 action = PF_DROP;
6535                 REASON_SET(&reason, PFRES_MEMORY);
6536         }
6537         if (r->rtableid >= 0)
6538                 M_SETFIB(m, r->rtableid);
6539
6540         if (r->scrub_flags & PFSTATE_SETPRIO) {
6541                 if (pd.tos & IPTOS_LOWDELAY)
6542                         pqid = 1;
6543                 if (pf_ieee8021q_setpcp(m, r->set_prio[pqid])) {
6544                         action = PF_DROP;
6545                         REASON_SET(&reason, PFRES_MEMORY);
6546                         log = 1;
6547                         DPFPRINTF(PF_DEBUG_MISC,
6548                             ("pf: failed to allocate 802.1q mtag\n"));
6549                 }
6550         }
6551
6552 #ifdef ALTQ
6553         if (action == PF_PASS && r->qid) {
6554                 if (pd.pf_mtag == NULL &&
6555                     ((pd.pf_mtag = pf_get_mtag(m)) == NULL)) {
6556                         action = PF_DROP;
6557                         REASON_SET(&reason, PFRES_MEMORY);
6558                 } else {
6559                         if (s != NULL)
6560                                 pd.pf_mtag->qid_hash = pf_state_hash(s);
6561                         if (pd.tos & IPTOS_LOWDELAY)
6562                                 pd.pf_mtag->qid = r->pqid;
6563                         else
6564                                 pd.pf_mtag->qid = r->qid;
6565                         /* Add hints for ecn. */
6566                         pd.pf_mtag->hdr = h;
6567                 }
6568         }
6569 #endif /* ALTQ */
6570
6571         if (dir == PF_IN && action == PF_PASS && (pd.proto == IPPROTO_TCP ||
6572             pd.proto == IPPROTO_UDP) && s != NULL && s->nat_rule.ptr != NULL &&
6573             (s->nat_rule.ptr->action == PF_RDR ||
6574             s->nat_rule.ptr->action == PF_BINAT) &&
6575             IN6_IS_ADDR_LOOPBACK(&pd.dst->v6))
6576                 m->m_flags |= M_SKIP_FIREWALL;
6577
6578         /* XXX: Anybody working on it?! */
6579         if (r->divert.port)
6580                 printf("pf: divert(9) is not supported for IPv6\n");
6581
6582         if (log) {
6583                 struct pf_rule *lr;
6584
6585                 if (s != NULL && s->nat_rule.ptr != NULL &&
6586                     s->nat_rule.ptr->log & PF_LOG_ALL)
6587                         lr = s->nat_rule.ptr;
6588                 else
6589                         lr = r;
6590                 PFLOG_PACKET(kif, m, AF_INET6, dir, reason, lr, a, ruleset,
6591                     &pd, (s == NULL));
6592         }
6593
6594         kif->pfik_bytes[1][dir == PF_OUT][action != PF_PASS] += pd.tot_len;
6595         kif->pfik_packets[1][dir == PF_OUT][action != PF_PASS]++;
6596
6597         if (action == PF_PASS || r->action == PF_DROP) {
6598                 dirndx = (dir == PF_OUT);
6599                 r->packets[dirndx]++;
6600                 r->bytes[dirndx] += pd.tot_len;
6601                 if (a != NULL) {
6602                         a->packets[dirndx]++;
6603                         a->bytes[dirndx] += pd.tot_len;
6604                 }
6605                 if (s != NULL) {
6606                         if (s->nat_rule.ptr != NULL) {
6607                                 s->nat_rule.ptr->packets[dirndx]++;
6608                                 s->nat_rule.ptr->bytes[dirndx] += pd.tot_len;
6609                         }
6610                         if (s->src_node != NULL) {
6611                                 s->src_node->packets[dirndx]++;
6612                                 s->src_node->bytes[dirndx] += pd.tot_len;
6613                         }
6614                         if (s->nat_src_node != NULL) {
6615                                 s->nat_src_node->packets[dirndx]++;
6616                                 s->nat_src_node->bytes[dirndx] += pd.tot_len;
6617                         }
6618                         dirndx = (dir == s->direction) ? 0 : 1;
6619                         s->packets[dirndx]++;
6620                         s->bytes[dirndx] += pd.tot_len;
6621                 }
6622                 tr = r;
6623                 nr = (s != NULL) ? s->nat_rule.ptr : pd.nat_rule;
6624                 if (nr != NULL && r == &V_pf_default_rule)
6625                         tr = nr;
6626                 if (tr->src.addr.type == PF_ADDR_TABLE)
6627                         pfr_update_stats(tr->src.addr.p.tbl,
6628                             (s == NULL) ? pd.src :
6629                             &s->key[(s->direction == PF_IN)]->addr[0],
6630                             pd.af, pd.tot_len, dir == PF_OUT,
6631                             r->action == PF_PASS, tr->src.neg);
6632                 if (tr->dst.addr.type == PF_ADDR_TABLE)
6633                         pfr_update_stats(tr->dst.addr.p.tbl,
6634                             (s == NULL) ? pd.dst :
6635                             &s->key[(s->direction == PF_IN)]->addr[1],
6636                             pd.af, pd.tot_len, dir == PF_OUT,
6637                             r->action == PF_PASS, tr->dst.neg);
6638         }
6639
6640         switch (action) {
6641         case PF_SYNPROXY_DROP:
6642                 m_freem(*m0);
6643         case PF_DEFER:
6644                 *m0 = NULL;
6645                 action = PF_PASS;
6646                 break;
6647         case PF_DROP:
6648                 m_freem(*m0);
6649                 *m0 = NULL;
6650                 break;
6651         default:
6652                 /* pf_route6() returns unlocked. */
6653                 if (r->rt) {
6654                         pf_route6(m0, r, dir, kif->pfik_ifp, s, &pd, inp);
6655                         return (action);
6656                 }
6657                 break;
6658         }
6659
6660         if (s)
6661                 PF_STATE_UNLOCK(s);
6662
6663         /* If reassembled packet passed, create new fragments. */
6664         if (action == PF_PASS && *m0 && (pflags & PFIL_FWD) &&
6665             (mtag = m_tag_find(m, PF_REASSEMBLED, NULL)) != NULL)
6666                 action = pf_refragment6(ifp, m0, mtag);
6667
6668         return (action);
6669 }
6670 #endif /* INET6 */