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
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD: src/sys/netinet/ip_fw_pfil.c,v 1.25.2.2 2008/04/25 10:26:30 oleg Exp $");
30 #if !defined(KLD_MODULE)
35 #error IPFIREWALL requires INET.
37 #endif /* KLD_MODULE */
38 #include "opt_inet6.h"
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/malloc.h>
44 #include <sys/module.h>
45 #include <sys/kernel.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h>
48 #include <sys/sysctl.h>
53 #include <netinet/in.h>
54 #include <netinet/ip.h>
55 #include <netinet/ip_var.h>
56 #include <netinet/ip_fw.h>
57 #include <netinet/ip_divert.h>
58 #include <netinet/ip_dummynet.h>
60 #include <netgraph/ng_ipfw.h>
62 #include <machine/in_cksum.h>
71 int ipfw_chg_hook(SYSCTL_HANDLER_ARGS);
74 ip_divert_packet_t *ip_divert_ptr = NULL;
77 ng_ipfw_input_t *ng_ipfw_input_p = NULL;
79 /* Forward declarations. */
80 static int ipfw_divert(struct mbuf **, int, int);
85 ipfw_check_in(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
88 struct ip_fw_args args;
89 struct ng_ipfw_tag *ng_tag;
94 #ifdef IPFIREWALL_FORWARD
95 struct m_tag *fwd_tag;
98 KASSERT(dir == PFIL_IN, ("ipfw_check_in wrong direction!"));
100 bzero(&args, sizeof(args));
102 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
104 if (ng_tag != NULL) {
105 KASSERT(ng_tag->dir == NG_IPFW_IN,
106 ("ng_ipfw tag with wrong direction"));
107 args.rule = ng_tag->rule;
108 m_tag_delete(*m0, (struct m_tag *)ng_tag);
112 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
114 struct dn_pkt_tag *dt;
116 dt = (struct dn_pkt_tag *)(dn_tag+1);
117 args.rule = dt->rule;
119 m_tag_delete(*m0, dn_tag);
124 ipfw = ipfw_chk(&args);
128 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
133 if (args.next_hop == NULL)
136 #ifdef IPFIREWALL_FORWARD
137 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
138 sizeof(struct sockaddr_in), M_NOWAIT);
141 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
142 m_tag_prepend(*m0, fwd_tag);
144 if (in_localip(args.next_hop->sin_addr))
145 (*m0)->m_flags |= M_FASTFWD_OURS;
148 break; /* not reached */
152 break; /* not reached */
155 if (ip_dn_io_ptr == NULL)
157 if (mtod(*m0, struct ip *)->ip_v == 4)
158 ip_dn_io_ptr(m0, DN_TO_IP_IN, &args);
159 else if (mtod(*m0, struct ip *)->ip_v == 6)
160 ip_dn_io_ptr(m0, DN_TO_IP6_IN, &args);
163 return 0; /* packet consumed */
170 divert = ipfw_divert(m0, DIV_DIR_IN, tee);
173 return 0; /* packet consumed */
176 goto again; /* continue with packet */
182 (void)ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 1);
183 goto again; /* continue with packet */
188 return ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 0);
191 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 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
229 if (ng_tag != NULL) {
230 KASSERT(ng_tag->dir == NG_IPFW_OUT,
231 ("ng_ipfw tag with wrong direction"));
232 args.rule = ng_tag->rule;
233 m_tag_delete(*m0, (struct m_tag *)ng_tag);
237 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
238 if (dn_tag != NULL) {
239 struct dn_pkt_tag *dt;
241 dt = (struct dn_pkt_tag *)(dn_tag+1);
242 args.rule = dt->rule;
244 m_tag_delete(*m0, dn_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 (ip_dn_io_ptr == NULL)
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);
293 return 0; /* packet consumed */
302 divert = ipfw_divert(m0, DIV_DIR_OUT, tee);
305 return 0; /* packet consumed */
308 goto again; /* continue with packet */
314 (void)ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 1);
315 goto again; /* continue with packet */
320 return ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 0);
323 goto again; /* continue with packet */
329 KASSERT(0, ("%s: unknown retval", __func__));
338 return 0; /* not filtered */
342 ipfw_divert(struct mbuf **m, int incoming, int tee)
345 * ipfw_chk() has already tagged the packet with the divert tag.
346 * If tee is set, copy packet and return original.
347 * If not tee, consume packet and send it to divert socket.
349 struct mbuf *clone, *reass;
355 /* Is divert module loaded? */
356 if (ip_divert_ptr == NULL)
359 /* Cloning needed for tee? */
361 clone = m_dup(*m, M_DONTWAIT);
365 /* In case m_dup was unable to allocate mbufs. */
370 * Divert listeners can only handle non-fragmented packets.
371 * However when tee is set we will *not* de-fragment the packets;
372 * Doing do would put the reassembly into double-jeopardy. On top
373 * of that someone doing a tee will probably want to get the packet
374 * in its original form.
376 ip = mtod(clone, struct ip *);
377 if (!tee && ip->ip_off & (IP_MF | IP_OFFMASK)) {
379 /* Reassemble packet. */
380 reass = ip_reass(clone);
383 * IP header checksum fixup after reassembly and leave header
384 * in network byte order.
387 ip = mtod(reass, struct ip *);
388 hlen = ip->ip_hl << 2;
389 ip->ip_len = htons(ip->ip_len);
390 ip->ip_off = htons(ip->ip_off);
392 if (hlen == sizeof(struct ip))
393 ip->ip_sum = in_cksum_hdr(ip);
395 ip->ip_sum = in_cksum(reass, hlen);
400 /* Convert header to network byte order. */
401 ip->ip_len = htons(ip->ip_len);
402 ip->ip_off = htons(ip->ip_off);
405 /* Do the dirty job... */
406 if (clone && ip_divert_ptr != NULL)
407 ip_divert_ptr(clone, incoming);
411 * For tee we leave the divert tag attached to original packet.
412 * It will then continue rule evaluation after the tee rule.
417 /* Packet diverted and consumed */
428 struct pfil_head *pfh_inet;
430 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
431 if (pfh_inet == NULL)
434 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
435 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
443 struct pfil_head *pfh_inet;
445 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
446 if (pfh_inet == NULL)
449 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
450 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
459 struct pfil_head *pfh_inet6;
461 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
462 if (pfh_inet6 == NULL)
465 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
466 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
474 struct pfil_head *pfh_inet6;
476 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
477 if (pfh_inet6 == NULL)
480 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
481 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
488 ipfw_chg_hook(SYSCTL_HANDLER_ARGS)
490 int enable = *(int *)arg1;
493 error = sysctl_handle_int(oidp, &enable, 0, req);
497 enable = (enable) ? 1 : 0;
499 if (enable == *(int *)arg1)
502 if (arg1 == &fw_enable) {
506 error = ipfw_unhook();
509 if (arg1 == &fw6_enable) {
511 error = ipfw6_hook();
513 error = ipfw6_unhook();
520 *(int *)arg1 = enable;
526 ipfw_modevent(module_t mod, int type, void *unused)
532 if ((err = ipfw_init()) != 0) {
533 printf("ipfw_init() error\n");
536 if ((err = ipfw_hook()) != 0) {
537 printf("ipfw_hook() error\n");
541 if ((err = ipfw6_hook()) != 0) {
542 printf("ipfw_hook() error\n");
549 if ((err = ipfw_unhook()) > 0)
552 if ((err = ipfw6_unhook()) > 0)
565 static moduledata_t ipfwmod = {
570 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY - 256);
571 MODULE_VERSION(ipfw, 2);