2 * Copyright (c) 2004 Andre Oppermann, Internet Business Solutions AG
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #if !defined(KLD_MODULE)
34 #error IPFIREWALL requires INET.
36 #endif /* KLD_MODULE */
37 #include "opt_inet6.h"
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/malloc.h>
43 #include <sys/module.h>
44 #include <sys/kernel.h>
45 #include <sys/socket.h>
46 #include <sys/socketvar.h>
47 #include <sys/sysctl.h>
48 #include <sys/ucred.h>
51 #include <net/route.h>
54 #include <netinet/in.h>
55 #include <netinet/in_systm.h>
56 #include <netinet/in_var.h>
57 #include <netinet/ip.h>
58 #include <netinet/ip_var.h>
59 #include <netinet/ip_fw.h>
60 #include <netinet/ip_divert.h>
61 #include <netinet/ip_dummynet.h>
63 #include <netgraph/ng_ipfw.h>
65 #include <machine/in_cksum.h>
72 int ipfw_chg_hook(SYSCTL_HANDLER_ARGS);
75 ip_dn_ruledel_t *ip_dn_ruledel_ptr = NULL;
78 ip_divert_packet_t *ip_divert_ptr = NULL;
81 ng_ipfw_input_t *ng_ipfw_input_p = NULL;
83 /* Forward declarations. */
84 static int ipfw_divert(struct mbuf **, int, int);
89 ipfw_check_in(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
92 struct ip_fw_args args;
93 struct ng_ipfw_tag *ng_tag;
98 #ifdef IPFIREWALL_FORWARD
99 struct m_tag *fwd_tag;
102 KASSERT(dir == PFIL_IN, ("ipfw_check_in wrong direction!"));
104 bzero(&args, sizeof(args));
106 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
108 struct dn_pkt_tag *dt;
110 dt = (struct dn_pkt_tag *)(dn_tag+1);
111 args.rule = dt->rule;
113 m_tag_delete(*m0, dn_tag);
116 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
118 if (ng_tag != NULL) {
119 KASSERT(ng_tag->dir == NG_IPFW_IN,
120 ("ng_ipfw tag with wrong direction"));
121 args.rule = ng_tag->rule;
122 m_tag_delete(*m0, (struct m_tag *)ng_tag);
128 ipfw = ipfw_chk(&args);
132 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
137 if (args.next_hop == NULL)
140 #ifdef IPFIREWALL_FORWARD
141 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
142 sizeof(struct sockaddr_in), M_NOWAIT);
145 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
146 m_tag_prepend(*m0, fwd_tag);
148 if (in_localip(args.next_hop->sin_addr))
149 (*m0)->m_flags |= M_FASTFWD_OURS;
152 break; /* not reached */
156 break; /* not reached */
159 if (!DUMMYNET_LOADED)
161 if (mtod(*m0, struct ip *)->ip_v == 4)
162 ip_dn_io_ptr(*m0, DN_TO_IP_IN, &args);
163 else if (mtod(*m0, struct ip *)->ip_v == 6)
164 ip_dn_io_ptr(*m0, DN_TO_IP6_IN, &args);
166 return 0; /* packet consumed */
173 divert = ipfw_divert(m0, DIV_DIR_IN, tee);
176 return 0; /* packet consumed */
179 goto again; /* continue with packet */
185 (void)ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 1);
186 goto again; /* continue with packet */
191 return ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 0);
194 KASSERT(0, ("%s: unknown retval", __func__));
203 return 0; /* not filtered */
207 ipfw_check_out(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
210 struct ip_fw_args args;
211 struct ng_ipfw_tag *ng_tag;
212 struct m_tag *dn_tag;
216 #ifdef IPFIREWALL_FORWARD
217 struct m_tag *fwd_tag;
220 KASSERT(dir == PFIL_OUT, ("ipfw_check_out wrong direction!"));
222 bzero(&args, sizeof(args));
224 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
225 if (dn_tag != NULL) {
226 struct dn_pkt_tag *dt;
228 dt = (struct dn_pkt_tag *)(dn_tag+1);
229 args.rule = dt->rule;
231 m_tag_delete(*m0, dn_tag);
234 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
236 if (ng_tag != NULL) {
237 KASSERT(ng_tag->dir == NG_IPFW_OUT,
238 ("ng_ipfw tag with wrong direction"));
239 args.rule = ng_tag->rule;
240 m_tag_delete(*m0, (struct m_tag *)ng_tag);
247 ipfw = ipfw_chk(&args);
251 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
256 if (args.next_hop == NULL)
258 #ifdef IPFIREWALL_FORWARD
259 /* Overwrite existing tag. */
260 fwd_tag = m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL);
261 if (fwd_tag == NULL) {
262 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
263 sizeof(struct sockaddr_in), M_NOWAIT);
267 m_tag_unlink(*m0, fwd_tag);
268 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
269 m_tag_prepend(*m0, fwd_tag);
271 if (in_localip(args.next_hop->sin_addr))
272 (*m0)->m_flags |= M_FASTFWD_OURS;
275 break; /* not reached */
279 break; /* not reached */
282 if (!DUMMYNET_LOADED)
284 if (mtod(*m0, struct ip *)->ip_v == 4)
285 ip_dn_io_ptr(*m0, DN_TO_IP_OUT, &args);
286 else if (mtod(*m0, struct ip *)->ip_v == 6)
287 ip_dn_io_ptr(*m0, DN_TO_IP6_OUT, &args);
289 return 0; /* packet consumed */
298 divert = ipfw_divert(m0, DIV_DIR_OUT, tee);
301 return 0; /* packet consumed */
304 goto again; /* continue with packet */
310 (void)ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 1);
311 goto again; /* continue with packet */
316 return ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 0);
319 KASSERT(0, ("%s: unknown retval", __func__));
328 return 0; /* not filtered */
332 ipfw_divert(struct mbuf **m, int incoming, int tee)
335 * ipfw_chk() has already tagged the packet with the divert tag.
336 * If tee is set, copy packet and return original.
337 * If not tee, consume packet and send it to divert socket.
339 struct mbuf *clone, *reass;
345 /* Is divert module loaded? */
346 if (ip_divert_ptr == NULL)
349 /* Cloning needed for tee? */
351 clone = m_dup(*m, M_DONTWAIT);
355 /* In case m_dup was unable to allocate mbufs. */
360 * Divert listeners can only handle non-fragmented packets.
361 * However when tee is set we will *not* de-fragment the packets;
362 * Doing do would put the reassembly into double-jeopardy. On top
363 * of that someone doing a tee will probably want to get the packet
364 * in its original form.
366 ip = mtod(clone, struct ip *);
367 if (!tee && ip->ip_off & (IP_MF | IP_OFFMASK)) {
369 /* Reassemble packet. */
370 reass = ip_reass(clone);
373 * IP header checksum fixup after reassembly and leave header
374 * in network byte order.
377 ip = mtod(reass, struct ip *);
378 hlen = ip->ip_hl << 2;
379 ip->ip_len = htons(ip->ip_len);
380 ip->ip_off = htons(ip->ip_off);
382 if (hlen == sizeof(struct ip))
383 ip->ip_sum = in_cksum_hdr(ip);
385 ip->ip_sum = in_cksum(reass, hlen);
390 /* Convert header to network byte order. */
391 ip->ip_len = htons(ip->ip_len);
392 ip->ip_off = htons(ip->ip_off);
395 /* Do the dirty job... */
396 if (clone && ip_divert_ptr != NULL)
397 ip_divert_ptr(clone, incoming);
401 * For tee we leave the divert tag attached to original packet.
402 * It will then continue rule evaluation after the tee rule.
407 /* Packet diverted and consumed */
418 struct pfil_head *pfh_inet;
420 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
421 if (pfh_inet == NULL)
424 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
425 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
433 struct pfil_head *pfh_inet;
435 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
436 if (pfh_inet == NULL)
439 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
440 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
449 struct pfil_head *pfh_inet6;
451 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
452 if (pfh_inet6 == NULL)
455 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
456 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
464 struct pfil_head *pfh_inet6;
466 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
467 if (pfh_inet6 == NULL)
470 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
471 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
478 ipfw_chg_hook(SYSCTL_HANDLER_ARGS)
480 int enable = *(int *)arg1;
483 error = sysctl_handle_int(oidp, &enable, 0, req);
487 enable = (enable) ? 1 : 0;
489 if (enable == *(int *)arg1)
492 if (arg1 == &fw_enable) {
496 error = ipfw_unhook();
499 if (arg1 == &fw6_enable) {
501 error = ipfw6_hook();
503 error = ipfw6_unhook();
510 *(int *)arg1 = enable;
516 ipfw_modevent(module_t mod, int type, void *unused)
522 if ((err = ipfw_init()) != 0) {
523 printf("ipfw_init() error\n");
526 if ((err = ipfw_hook()) != 0) {
527 printf("ipfw_hook() error\n");
531 if ((err = ipfw6_hook()) != 0) {
532 printf("ipfw_hook() error\n");
539 if ((err = ipfw_unhook()) > 0)
542 if ((err = ipfw6_unhook()) > 0)
555 static moduledata_t ipfwmod = {
560 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
561 MODULE_VERSION(ipfw, 2);