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("$FreeBSD$");
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>
69 int ipfw_chg_hook(SYSCTL_HANDLER_ARGS);
72 ip_dn_ruledel_t *ip_dn_ruledel_ptr = NULL;
75 ip_divert_packet_t *ip_divert_ptr = NULL;
78 ng_ipfw_input_t *ng_ipfw_input_p = NULL;
80 /* Forward declarations. */
81 static int ipfw_divert(struct mbuf **, int, int);
86 ipfw_check_in(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
89 struct ip_fw_args args;
90 struct ng_ipfw_tag *ng_tag;
95 #ifdef IPFIREWALL_FORWARD
96 struct m_tag *fwd_tag;
99 KASSERT(dir == PFIL_IN, ("ipfw_check_in wrong direction!"));
101 bzero(&args, sizeof(args));
103 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
105 if (ng_tag != NULL) {
106 KASSERT(ng_tag->dir == NG_IPFW_IN,
107 ("ng_ipfw tag with wrong direction"));
108 args.rule = ng_tag->rule;
109 m_tag_delete(*m0, (struct m_tag *)ng_tag);
113 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
115 struct dn_pkt_tag *dt;
117 dt = (struct dn_pkt_tag *)(dn_tag+1);
118 args.rule = dt->rule;
120 m_tag_delete(*m0, dn_tag);
125 ipfw = ipfw_chk(&args);
129 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
134 if (args.next_hop == NULL)
137 #ifdef IPFIREWALL_FORWARD
138 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
139 sizeof(struct sockaddr_in), M_NOWAIT);
142 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
143 m_tag_prepend(*m0, fwd_tag);
145 if (in_localip(args.next_hop->sin_addr))
146 (*m0)->m_flags |= M_FASTFWD_OURS;
149 break; /* not reached */
153 break; /* not reached */
156 if (!DUMMYNET_LOADED)
158 if (mtod(*m0, struct ip *)->ip_v == 4)
159 ip_dn_io_ptr(m0, DN_TO_IP_IN, &args);
160 else if (mtod(*m0, struct ip *)->ip_v == 6)
161 ip_dn_io_ptr(m0, DN_TO_IP6_IN, &args);
164 return 0; /* packet consumed */
171 divert = ipfw_divert(m0, DIV_DIR_IN, tee);
174 return 0; /* packet consumed */
177 goto again; /* continue with packet */
183 (void)ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 1);
184 goto again; /* continue with packet */
189 return ng_ipfw_input_p(m0, NG_IPFW_IN, &args, 0);
192 goto again; /* continue with packet */
195 KASSERT(0, ("%s: unknown retval", __func__));
204 return 0; /* not filtered */
208 ipfw_check_out(void *arg, struct mbuf **m0, struct ifnet *ifp, int dir,
211 struct ip_fw_args args;
212 struct ng_ipfw_tag *ng_tag;
213 struct m_tag *dn_tag;
217 #ifdef IPFIREWALL_FORWARD
218 struct m_tag *fwd_tag;
221 KASSERT(dir == PFIL_OUT, ("ipfw_check_out wrong direction!"));
223 bzero(&args, sizeof(args));
225 ng_tag = (struct ng_ipfw_tag *)m_tag_locate(*m0, NGM_IPFW_COOKIE, 0,
227 if (ng_tag != NULL) {
228 KASSERT(ng_tag->dir == NG_IPFW_OUT,
229 ("ng_ipfw tag with wrong direction"));
230 args.rule = ng_tag->rule;
231 m_tag_delete(*m0, (struct m_tag *)ng_tag);
235 dn_tag = m_tag_find(*m0, PACKET_TAG_DUMMYNET, NULL);
236 if (dn_tag != NULL) {
237 struct dn_pkt_tag *dt;
239 dt = (struct dn_pkt_tag *)(dn_tag+1);
240 args.rule = dt->rule;
242 m_tag_delete(*m0, dn_tag);
248 ipfw = ipfw_chk(&args);
252 KASSERT(*m0 != NULL || ipfw == IP_FW_DENY, ("%s: m0 is NULL",
257 if (args.next_hop == NULL)
259 #ifdef IPFIREWALL_FORWARD
260 /* Overwrite existing tag. */
261 fwd_tag = m_tag_find(*m0, PACKET_TAG_IPFORWARD, NULL);
262 if (fwd_tag == NULL) {
263 fwd_tag = m_tag_get(PACKET_TAG_IPFORWARD,
264 sizeof(struct sockaddr_in), M_NOWAIT);
268 m_tag_unlink(*m0, fwd_tag);
269 bcopy(args.next_hop, (fwd_tag+1), sizeof(struct sockaddr_in));
270 m_tag_prepend(*m0, fwd_tag);
272 if (in_localip(args.next_hop->sin_addr))
273 (*m0)->m_flags |= M_FASTFWD_OURS;
276 break; /* not reached */
280 break; /* not reached */
283 if (!DUMMYNET_LOADED)
285 if (mtod(*m0, struct ip *)->ip_v == 4)
286 ip_dn_io_ptr(m0, DN_TO_IP_OUT, &args);
287 else if (mtod(*m0, struct ip *)->ip_v == 6)
288 ip_dn_io_ptr(m0, DN_TO_IP6_OUT, &args);
291 return 0; /* packet consumed */
300 divert = ipfw_divert(m0, DIV_DIR_OUT, tee);
303 return 0; /* packet consumed */
306 goto again; /* continue with packet */
312 (void)ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 1);
313 goto again; /* continue with packet */
318 return ng_ipfw_input_p(m0, NG_IPFW_OUT, &args, 0);
321 goto again; /* continue with packet */
324 KASSERT(0, ("%s: unknown retval", __func__));
333 return 0; /* not filtered */
337 ipfw_divert(struct mbuf **m, int incoming, int tee)
340 * ipfw_chk() has already tagged the packet with the divert tag.
341 * If tee is set, copy packet and return original.
342 * If not tee, consume packet and send it to divert socket.
344 struct mbuf *clone, *reass;
350 /* Is divert module loaded? */
351 if (ip_divert_ptr == NULL)
354 /* Cloning needed for tee? */
356 clone = m_dup(*m, M_DONTWAIT);
360 /* In case m_dup was unable to allocate mbufs. */
365 * Divert listeners can only handle non-fragmented packets.
366 * However when tee is set we will *not* de-fragment the packets;
367 * Doing do would put the reassembly into double-jeopardy. On top
368 * of that someone doing a tee will probably want to get the packet
369 * in its original form.
371 ip = mtod(clone, struct ip *);
372 if (!tee && ip->ip_off & (IP_MF | IP_OFFMASK)) {
374 /* Reassemble packet. */
375 reass = ip_reass(clone);
378 * IP header checksum fixup after reassembly and leave header
379 * in network byte order.
382 ip = mtod(reass, struct ip *);
383 hlen = ip->ip_hl << 2;
384 ip->ip_len = htons(ip->ip_len);
385 ip->ip_off = htons(ip->ip_off);
387 if (hlen == sizeof(struct ip))
388 ip->ip_sum = in_cksum_hdr(ip);
390 ip->ip_sum = in_cksum(reass, hlen);
395 /* Convert header to network byte order. */
396 ip->ip_len = htons(ip->ip_len);
397 ip->ip_off = htons(ip->ip_off);
400 /* Do the dirty job... */
401 if (clone && ip_divert_ptr != NULL)
402 ip_divert_ptr(clone, incoming);
406 * For tee we leave the divert tag attached to original packet.
407 * It will then continue rule evaluation after the tee rule.
412 /* Packet diverted and consumed */
423 struct pfil_head *pfh_inet;
425 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
426 if (pfh_inet == NULL)
429 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
430 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
438 struct pfil_head *pfh_inet;
440 pfh_inet = pfil_head_get(PFIL_TYPE_AF, AF_INET);
441 if (pfh_inet == NULL)
444 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet);
445 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet);
454 struct pfil_head *pfh_inet6;
456 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
457 if (pfh_inet6 == NULL)
460 pfil_add_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
461 pfil_add_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
469 struct pfil_head *pfh_inet6;
471 pfh_inet6 = pfil_head_get(PFIL_TYPE_AF, AF_INET6);
472 if (pfh_inet6 == NULL)
475 pfil_remove_hook(ipfw_check_in, NULL, PFIL_IN | PFIL_WAITOK, pfh_inet6);
476 pfil_remove_hook(ipfw_check_out, NULL, PFIL_OUT | PFIL_WAITOK, pfh_inet6);
483 ipfw_chg_hook(SYSCTL_HANDLER_ARGS)
485 int enable = *(int *)arg1;
488 error = sysctl_handle_int(oidp, &enable, 0, req);
492 enable = (enable) ? 1 : 0;
494 if (enable == *(int *)arg1)
497 if (arg1 == &fw_enable) {
501 error = ipfw_unhook();
504 if (arg1 == &fw6_enable) {
506 error = ipfw6_hook();
508 error = ipfw6_unhook();
515 *(int *)arg1 = enable;
521 ipfw_modevent(module_t mod, int type, void *unused)
527 if ((err = ipfw_init()) != 0) {
528 printf("ipfw_init() error\n");
531 if ((err = ipfw_hook()) != 0) {
532 printf("ipfw_hook() error\n");
536 if ((err = ipfw6_hook()) != 0) {
537 printf("ipfw_hook() error\n");
544 if ((err = ipfw_unhook()) > 0)
547 if ((err = ipfw6_unhook()) > 0)
560 static moduledata_t ipfwmod = {
565 DECLARE_MODULE(ipfw, ipfwmod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY - 256);
566 MODULE_VERSION(ipfw, 2);