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 goto again; /* continue with packet */
197 KASSERT(0, ("%s: unknown retval", __func__));
206 return 0; /* not filtered */
210 ipfw_check_out(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
213 struct ip_fw_args args;
214 struct ng_ipfw_tag *ng_tag;
215 struct m_tag *dn_tag;
219 #ifdef IPFIREWALL_FORWARD
220 struct m_tag *fwd_tag;
223 KASSERT(dir == PFIL_OUT, ("ipfw_check_out wrong direction!"));
225 bzero(&args, sizeof(args));
227 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
228 if (dn_tag != NULL) {
229 struct dn_pkt_tag *dt;
231 dt = (struct dn_pkt_tag *)(dn_tag+1);
232 args.rule = dt->rule;
234 m_tag_delete(*m0, dn_tag);
237 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
239 if (ng_tag != NULL) {
240 KASSERT(ng_tag->dir == NG_IPFW_OUT,
241 ("ng_ipfw tag with wrong direction"));
242 args.rule = ng_tag->rule;
243 m_tag_delete(*m0, (struct m_tag *)ng_tag);
250 ipfw = ipfw_chk(&args);
254 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
259 if (args.next_hop == NULL)
261 #ifdef IPFIREWALL_FORWARD
262 /* Overwrite existing tag. */
263 fwd_tag = m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL);
264 if (fwd_tag == NULL) {
265 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
266 sizeof(struct sockaddr_in), M_NOWAIT);
270 m_tag_unlink(*m0, fwd_tag);
271 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
272 m_tag_prepend(*m0, fwd_tag);
274 if (in_localip(args.next_hop->sin_addr))
275 (*m0)->m_flags |= M_FASTFWD_OURS;
278 break; /* not reached */
282 break; /* not reached */
285 if (!DUMMYNET_LOADED)
287 if (mtod(*m0, struct ip *)->ip_v == 4)
288 ip_dn_io_ptr(*m0, DN_TO_IP_OUT, &args);
289 else if (mtod(*m0, struct ip *)->ip_v == 6)
290 ip_dn_io_ptr(*m0, DN_TO_IP6_OUT, &args);
292 return 0; /* packet consumed */
301 divert = ipfw_divert(m0, DIV_DIR_OUT, tee);
304 return 0; /* packet consumed */
307 goto again; /* continue with packet */
313 (void)ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 1);
314 goto again; /* continue with packet */
319 return ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 0);
322 goto again; /* continue with packet */
325 KASSERT(0, ("%s: unknown retval", __func__));
334 return 0; /* not filtered */
338 ipfw_divert(struct mbuf **m, int incoming, int tee)
341 * ipfw_chk() has already tagged the packet with the divert tag.
342 * If tee is set, copy packet and return original.
343 * If not tee, consume packet and send it to divert socket.
345 struct mbuf *clone, *reass;
351 /* Is divert module loaded? */
352 if (ip_divert_ptr == NULL)
355 /* Cloning needed for tee? */
357 clone = m_dup(*m, M_DONTWAIT);
361 /* In case m_dup was unable to allocate mbufs. */
366 * Divert listeners can only handle non-fragmented packets.
367 * However when tee is set we will *not* de-fragment the packets;
368 * Doing do would put the reassembly into double-jeopardy. On top
369 * of that someone doing a tee will probably want to get the packet
370 * in its original form.
372 ip = mtod(clone, struct ip *);
373 if (!tee && ip->ip_off & (IP_MF | IP_OFFMASK)) {
375 /* Reassemble packet. */
376 reass = ip_reass(clone);
379 * IP header checksum fixup after reassembly and leave header
380 * in network byte order.
383 ip = mtod(reass, struct ip *);
384 hlen = ip->ip_hl << 2;
385 ip->ip_len = htons(ip->ip_len);
386 ip->ip_off = htons(ip->ip_off);
388 if (hlen == sizeof(struct ip))
389 ip->ip_sum = in_cksum_hdr(ip);
391 ip->ip_sum = in_cksum(reass, hlen);
396 /* Convert header to network byte order. */
397 ip->ip_len = htons(ip->ip_len);
398 ip->ip_off = htons(ip->ip_off);
401 /* Do the dirty job... */
402 if (clone && ip_divert_ptr != NULL)
403 ip_divert_ptr(clone, incoming);
407 * For tee we leave the divert tag attached to original packet.
408 * It will then continue rule evaluation after the tee rule.
413 /* Packet diverted and consumed */
424 struct pfil_head *pfh_inet;
426 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
427 if (pfh_inet == NULL)
430 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
431 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
439 struct pfil_head *pfh_inet;
441 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
442 if (pfh_inet == NULL)
445 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
446 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
455 struct pfil_head *pfh_inet6;
457 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
458 if (pfh_inet6 == NULL)
461 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
462 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
470 struct pfil_head *pfh_inet6;
472 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
473 if (pfh_inet6 == NULL)
476 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
477 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
484 ipfw_chg_hook(SYSCTL_HANDLER_ARGS)
486 int enable = *(int *)arg1;
489 error = sysctl_handle_int(oidp, &enable, 0, req);
493 enable = (enable) ? 1 : 0;
495 if (enable == *(int *)arg1)
498 if (arg1 == &fw_enable) {
502 error = ipfw_unhook();
505 if (arg1 == &fw6_enable) {
507 error = ipfw6_hook();
509 error = ipfw6_unhook();
516 *(int *)arg1 = enable;
522 ipfw_modevent(module_t mod, int type, void *unused)
528 if ((err = ipfw_init()) != 0) {
529 printf("ipfw_init() error\n");
532 if ((err = ipfw_hook()) != 0) {
533 printf("ipfw_hook() error\n");
537 if ((err = ipfw6_hook()) != 0) {
538 printf("ipfw_hook() error\n");
545 if ((err = ipfw_unhook()) > 0)
548 if ((err = ipfw6_unhook()) > 0)
561 static moduledata_t ipfwmod = {
566 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
567 MODULE_VERSION(ipfw, 2);