1/*-
2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: head/sys/netinet6/ip6_ipsec.c 262763 2014-03-05 01:17:47Z glebius $");
32
33#include "opt_inet.h"
34#include "opt_inet6.h"
35#include "opt_ipsec.h"
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/kernel.h>
40#include <sys/mac.h>
41#include <sys/malloc.h>
42#include <sys/mbuf.h>
43#include <sys/protosw.h>
44#include <sys/socket.h>
45#include <sys/socketvar.h>
46#include <sys/sysctl.h>
47#include <sys/syslog.h>
48
49#include <net/if.h>
50#include <net/if_var.h>
51#include <net/route.h>
52#include <net/vnet.h>
53
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/ip6.h>
59#include <netinet/in_pcb.h>
60#include <netinet/ip_var.h>
61#include <netinet/ip_options.h>
62
63#include <machine/in_cksum.h>
64
65#ifdef IPSEC
66#include <netipsec/ipsec.h>
67#include <netipsec/ipsec6.h>
68#include <netipsec/xform.h>
69#include <netipsec/key.h>
70#ifdef IPSEC_DEBUG
71#include <netipsec/key_debug.h>
72#else
73#define KEYDEBUG(lev,arg)
74#endif
75#endif /*IPSEC*/
76
77#include <netinet6/ip6_ipsec.h>
78#include <netinet6/ip6_var.h>
79
80extern struct protosw inet6sw[];
81
82
83#ifdef INET6
84#ifdef IPSEC
85#ifdef IPSEC_FILTERTUNNEL
86static VNET_DEFINE(int, ip6_ipsec6_filtertunnel) = 1;
87#else
88static VNET_DEFINE(int, ip6_ipsec6_filtertunnel) = 0;
89#endif
90#define V_ip6_ipsec6_filtertunnel VNET(ip6_ipsec6_filtertunnel)
91
92SYSCTL_DECL(_net_inet6_ipsec6);
93SYSCTL_VNET_INT(_net_inet6_ipsec6, OID_AUTO,
94 filtertunnel, CTLFLAG_RW, &VNET_NAME(ip6_ipsec6_filtertunnel), 0,
95 "If set filter packets from an IPsec tunnel.");
96#endif /* IPSEC */
97#endif /* INET6 */
98
99/*
100 * Check if we have to jump over firewall processing for this packet.
101 * Called from ip6_input().
102 * 1 = jump over firewall, 0 = packet goes through firewall.
103 */
104int
105ip6_ipsec_filtertunnel(struct mbuf *m)
106{
107#ifdef IPSEC
108
109 /*
110 * Bypass packet filtering for packets previously handled by IPsec.
111 */
112 if (!V_ip6_ipsec6_filtertunnel &&
113 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL)
114 return 1;
115#endif
116 return 0;
117}
118
119/*
120 * Check if this packet has an active SA and needs to be dropped instead
121 * of forwarded.
122 * Called from ip6_input().
123 * 1 = drop packet, 0 = forward packet.
124 */
125int
126ip6_ipsec_fwd(struct mbuf *m)
127{
128#ifdef IPSEC
129 struct m_tag *mtag;
130 struct tdb_ident *tdbi;
131 struct secpolicy *sp;
132 int error;
133 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
134 if (mtag != NULL) {
135 tdbi = (struct tdb_ident *)(mtag + 1);
136 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
137 } else {
138 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
139 IP_FORWARDING, &error);
140 }
141 if (sp == NULL) { /* NB: can happen if error */
142 /*XXX error stat???*/
143 DPRINTF(("%s: no SP for forwarding\n", __func__)); /*XXX*/
144 return 1;
145 }
146
147 /*
148 * Check security policy against packet attributes.
149 */
150 error = ipsec_in_reject(sp, m);
151 KEY_FREESP(&sp);
152 if (error) {
153 IP6STAT_INC(ip6s_cantforward);
154 return 1;
155 }
156#endif /* IPSEC */
157 return 0;
158}
159
160/*
161 * Check if protocol type doesn't have a further header and do IPSEC
162 * decryption or reject right now. Protocols with further headers get
163 * their IPSEC treatment within the protocol specific processing.
164 * Called from ip6_input().
165 * 1 = drop packet, 0 = continue processing packet.
166 */
167int
168ip6_ipsec_input(struct mbuf *m, int nxt)
169{
170#ifdef IPSEC
171 struct m_tag *mtag;
172 struct tdb_ident *tdbi;
173 struct secpolicy *sp;
174 int error;
175 /*
176 * enforce IPsec policy checking if we are seeing last header.
177 * note that we do not visit this with protocols with pcb layer
178 * code - like udp/tcp/raw ip.
179 */
180 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
181 ipsec6_in_reject(m, NULL)) {
182
183 /*
184 * Check if the packet has already had IPsec processing
185 * done. If so, then just pass it along. This tag gets
186 * set during AH, ESP, etc. input handling, before the
187 * packet is returned to the ip input queue for delivery.
188 */
189 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
190 if (mtag != NULL) {
191 tdbi = (struct tdb_ident *)(mtag + 1);
192 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
193 } else {
194 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
195 IP_FORWARDING, &error);
196 }
197 if (sp != NULL) {
198 /*
199 * Check security policy against packet attributes.
200 */
201 error = ipsec_in_reject(sp, m);
202 KEY_FREESP(&sp);
203 } else {
204 /* XXX error stat??? */
205 error = EINVAL;
206 DPRINTF(("%s: no SP, packet discarded\n", __func__));/*XXX*/
207 return 1;
208 }
209 if (error)
210 return 1;
211 }
212#endif /* IPSEC */
213 return 0;
214}
215
216/*
217 * Called from ip6_output().
218 * 1 = drop packet, 0 = continue processing packet,
219 * -1 = packet was reinjected and stop processing packet
220 */
221
222int
223ip6_ipsec_output(struct mbuf **m, struct inpcb *inp, int *flags, int *error,
224 struct ifnet **ifp, struct secpolicy **sp)
225{
226#ifdef IPSEC
227 struct tdb_ident *tdbi;
228 struct m_tag *mtag;
229 /* XXX int s; */
230 if (sp == NULL)
231 return 1;
232 mtag = m_tag_find(*m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
233 if (mtag != NULL) {
234 tdbi = (struct tdb_ident *)(mtag + 1);
235 *sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
236 if (*sp == NULL)
237 *error = -EINVAL; /* force silent drop */
238 m_tag_delete(*m, mtag);
239 } else {
240 *sp = ipsec4_checkpolicy(*m, IPSEC_DIR_OUTBOUND, *flags,
241 error, inp);
242 }
243
244 /*
245 * There are four return cases:
246 * sp != NULL apply IPsec policy
247 * sp == NULL, error == 0 no IPsec handling needed
248 * sp == NULL, error == -EINVAL discard packet w/o error
249 * sp == NULL, error != 0 discard packet, report error
250 */
251 if (*sp != NULL) {
252 /* Loop detection, check if ipsec processing already done */
253 KASSERT((*sp)->req != NULL, ("ip_output: no ipsec request"));
254 for (mtag = m_tag_first(*m); mtag != NULL;
255 mtag = m_tag_next(*m, mtag)) {
256 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
257 continue;
258 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
259 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
260 continue;
261 /*
262 * Check if policy has no SA associated with it.
263 * This can happen when an SP has yet to acquire
264 * an SA; e.g. on first reference. If it occurs,
265 * then we let ipsec4_process_packet do its thing.
266 */
267 if ((*sp)->req->sav == NULL)
268 break;
269 tdbi = (struct tdb_ident *)(mtag + 1);
270 if (tdbi->spi == (*sp)->req->sav->spi &&
271 tdbi->proto == (*sp)->req->sav->sah->saidx.proto &&
272 bcmp(&tdbi->dst, &(*sp)->req->sav->sah->saidx.dst,
273 sizeof (union sockaddr_union)) == 0) {
274 /*
275 * No IPsec processing is needed, free
276 * reference to SP.
277 *
278 * NB: null pointer to avoid free at
279 * done: below.
280 */
281 KEY_FREESP(sp), *sp = NULL;
282 goto done;
283 }
284 }
285
286 /*
287 * Do delayed checksums now because we send before
288 * this is done in the normal processing path.
289 * For IPv6 we do delayed checksums in ip6_output.c.
290 */
291#ifdef INET
292 if ((*m)->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
293 ipseclog((LOG_DEBUG,
294 "%s: we do not support IPv4 over IPv6", __func__));
295 in_delayed_cksum(*m);
296 (*m)->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
297 }
298#endif
299
300 /*
301 * Preserve KAME behaviour: ENOENT can be returned
302 * when an SA acquire is in progress. Don't propagate
303 * this to user-level; it confuses applications.
304 *
305 * XXX this will go away when the SADB is redone.
306 */
307 if (*error == ENOENT)
308 *error = 0;
309 goto do_ipsec;
310 } else { /* sp == NULL */
311 if (*error != 0) {
312 /*
313 * Hack: -EINVAL is used to signal that a packet
314 * should be silently discarded. This is typically
315 * because we asked key management for an SA and
316 * it was delayed (e.g. kicked up to IKE).
317 */
318 if (*error == -EINVAL)
319 *error = 0;
320 goto bad;
321 } else {
322 /* No IPsec processing for this packet. */
323 }
324 }
325done:
326 return 0;
327do_ipsec:
328 return -1;
329bad:
330 return 1;
331#endif /* IPSEC */
332 return 0;
333}
334
335#if 0
336/*
337 * Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
338 * Called from ip_forward().
339 * Returns MTU suggestion for ICMP needfrag reply.
340 */
341int
342ip6_ipsec_mtu(struct mbuf *m)
343{
344 int mtu = 0;
345 /*
346 * If the packet is routed over IPsec tunnel, tell the
347 * originator the tunnel MTU.
348 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
349 * XXX quickhack!!!
350 */
351#ifdef IPSEC
352 struct secpolicy *sp = NULL;
353 int ipsecerror;
354 int ipsechdr;
355 struct route *ro;
356 sp = ipsec_getpolicybyaddr(m,
357 IPSEC_DIR_OUTBOUND,
358 IP_FORWARDING,
359 &ipsecerror);
360 if (sp != NULL) {
361 /* count IPsec header size */
362 ipsechdr = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL);
363
364 /*
365 * find the correct route for outer IPv4
366 * header, compute tunnel MTU.
367 */
368 if (sp->req != NULL &&
369 sp->req->sav != NULL &&
370 sp->req->sav->sah != NULL) {
371 ro = &sp->req->sav->sah->route_cache.sa_route;
372 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
373 mtu = ro->ro_rt->rt_mtu ? ro->ro_rt->rt_mtu :
374 ro->ro_rt->rt_ifp->if_mtu;
375 mtu -= ipsechdr;
376 }
377 }
378 KEY_FREESP(&sp);
379 }
380#endif /* IPSEC */
381 /* XXX else case missing. */
382 return mtu;
383}
384#endif
2 * Copyright (c) 1982, 1986, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
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.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: head/sys/netinet6/ip6_ipsec.c 262763 2014-03-05 01:17:47Z glebius $");
32
33#include "opt_inet.h"
34#include "opt_inet6.h"
35#include "opt_ipsec.h"
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/kernel.h>
40#include <sys/mac.h>
41#include <sys/malloc.h>
42#include <sys/mbuf.h>
43#include <sys/protosw.h>
44#include <sys/socket.h>
45#include <sys/socketvar.h>
46#include <sys/sysctl.h>
47#include <sys/syslog.h>
48
49#include <net/if.h>
50#include <net/if_var.h>
51#include <net/route.h>
52#include <net/vnet.h>
53
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/ip6.h>
59#include <netinet/in_pcb.h>
60#include <netinet/ip_var.h>
61#include <netinet/ip_options.h>
62
63#include <machine/in_cksum.h>
64
65#ifdef IPSEC
66#include <netipsec/ipsec.h>
67#include <netipsec/ipsec6.h>
68#include <netipsec/xform.h>
69#include <netipsec/key.h>
70#ifdef IPSEC_DEBUG
71#include <netipsec/key_debug.h>
72#else
73#define KEYDEBUG(lev,arg)
74#endif
75#endif /*IPSEC*/
76
77#include <netinet6/ip6_ipsec.h>
78#include <netinet6/ip6_var.h>
79
80extern struct protosw inet6sw[];
81
82
83#ifdef INET6
84#ifdef IPSEC
85#ifdef IPSEC_FILTERTUNNEL
86static VNET_DEFINE(int, ip6_ipsec6_filtertunnel) = 1;
87#else
88static VNET_DEFINE(int, ip6_ipsec6_filtertunnel) = 0;
89#endif
90#define V_ip6_ipsec6_filtertunnel VNET(ip6_ipsec6_filtertunnel)
91
92SYSCTL_DECL(_net_inet6_ipsec6);
93SYSCTL_VNET_INT(_net_inet6_ipsec6, OID_AUTO,
94 filtertunnel, CTLFLAG_RW, &VNET_NAME(ip6_ipsec6_filtertunnel), 0,
95 "If set filter packets from an IPsec tunnel.");
96#endif /* IPSEC */
97#endif /* INET6 */
98
99/*
100 * Check if we have to jump over firewall processing for this packet.
101 * Called from ip6_input().
102 * 1 = jump over firewall, 0 = packet goes through firewall.
103 */
104int
105ip6_ipsec_filtertunnel(struct mbuf *m)
106{
107#ifdef IPSEC
108
109 /*
110 * Bypass packet filtering for packets previously handled by IPsec.
111 */
112 if (!V_ip6_ipsec6_filtertunnel &&
113 m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL)
114 return 1;
115#endif
116 return 0;
117}
118
119/*
120 * Check if this packet has an active SA and needs to be dropped instead
121 * of forwarded.
122 * Called from ip6_input().
123 * 1 = drop packet, 0 = forward packet.
124 */
125int
126ip6_ipsec_fwd(struct mbuf *m)
127{
128#ifdef IPSEC
129 struct m_tag *mtag;
130 struct tdb_ident *tdbi;
131 struct secpolicy *sp;
132 int error;
133 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
134 if (mtag != NULL) {
135 tdbi = (struct tdb_ident *)(mtag + 1);
136 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
137 } else {
138 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
139 IP_FORWARDING, &error);
140 }
141 if (sp == NULL) { /* NB: can happen if error */
142 /*XXX error stat???*/
143 DPRINTF(("%s: no SP for forwarding\n", __func__)); /*XXX*/
144 return 1;
145 }
146
147 /*
148 * Check security policy against packet attributes.
149 */
150 error = ipsec_in_reject(sp, m);
151 KEY_FREESP(&sp);
152 if (error) {
153 IP6STAT_INC(ip6s_cantforward);
154 return 1;
155 }
156#endif /* IPSEC */
157 return 0;
158}
159
160/*
161 * Check if protocol type doesn't have a further header and do IPSEC
162 * decryption or reject right now. Protocols with further headers get
163 * their IPSEC treatment within the protocol specific processing.
164 * Called from ip6_input().
165 * 1 = drop packet, 0 = continue processing packet.
166 */
167int
168ip6_ipsec_input(struct mbuf *m, int nxt)
169{
170#ifdef IPSEC
171 struct m_tag *mtag;
172 struct tdb_ident *tdbi;
173 struct secpolicy *sp;
174 int error;
175 /*
176 * enforce IPsec policy checking if we are seeing last header.
177 * note that we do not visit this with protocols with pcb layer
178 * code - like udp/tcp/raw ip.
179 */
180 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
181 ipsec6_in_reject(m, NULL)) {
182
183 /*
184 * Check if the packet has already had IPsec processing
185 * done. If so, then just pass it along. This tag gets
186 * set during AH, ESP, etc. input handling, before the
187 * packet is returned to the ip input queue for delivery.
188 */
189 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
190 if (mtag != NULL) {
191 tdbi = (struct tdb_ident *)(mtag + 1);
192 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
193 } else {
194 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
195 IP_FORWARDING, &error);
196 }
197 if (sp != NULL) {
198 /*
199 * Check security policy against packet attributes.
200 */
201 error = ipsec_in_reject(sp, m);
202 KEY_FREESP(&sp);
203 } else {
204 /* XXX error stat??? */
205 error = EINVAL;
206 DPRINTF(("%s: no SP, packet discarded\n", __func__));/*XXX*/
207 return 1;
208 }
209 if (error)
210 return 1;
211 }
212#endif /* IPSEC */
213 return 0;
214}
215
216/*
217 * Called from ip6_output().
218 * 1 = drop packet, 0 = continue processing packet,
219 * -1 = packet was reinjected and stop processing packet
220 */
221
222int
223ip6_ipsec_output(struct mbuf **m, struct inpcb *inp, int *flags, int *error,
224 struct ifnet **ifp, struct secpolicy **sp)
225{
226#ifdef IPSEC
227 struct tdb_ident *tdbi;
228 struct m_tag *mtag;
229 /* XXX int s; */
230 if (sp == NULL)
231 return 1;
232 mtag = m_tag_find(*m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
233 if (mtag != NULL) {
234 tdbi = (struct tdb_ident *)(mtag + 1);
235 *sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
236 if (*sp == NULL)
237 *error = -EINVAL; /* force silent drop */
238 m_tag_delete(*m, mtag);
239 } else {
240 *sp = ipsec4_checkpolicy(*m, IPSEC_DIR_OUTBOUND, *flags,
241 error, inp);
242 }
243
244 /*
245 * There are four return cases:
246 * sp != NULL apply IPsec policy
247 * sp == NULL, error == 0 no IPsec handling needed
248 * sp == NULL, error == -EINVAL discard packet w/o error
249 * sp == NULL, error != 0 discard packet, report error
250 */
251 if (*sp != NULL) {
252 /* Loop detection, check if ipsec processing already done */
253 KASSERT((*sp)->req != NULL, ("ip_output: no ipsec request"));
254 for (mtag = m_tag_first(*m); mtag != NULL;
255 mtag = m_tag_next(*m, mtag)) {
256 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
257 continue;
258 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
259 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
260 continue;
261 /*
262 * Check if policy has no SA associated with it.
263 * This can happen when an SP has yet to acquire
264 * an SA; e.g. on first reference. If it occurs,
265 * then we let ipsec4_process_packet do its thing.
266 */
267 if ((*sp)->req->sav == NULL)
268 break;
269 tdbi = (struct tdb_ident *)(mtag + 1);
270 if (tdbi->spi == (*sp)->req->sav->spi &&
271 tdbi->proto == (*sp)->req->sav->sah->saidx.proto &&
272 bcmp(&tdbi->dst, &(*sp)->req->sav->sah->saidx.dst,
273 sizeof (union sockaddr_union)) == 0) {
274 /*
275 * No IPsec processing is needed, free
276 * reference to SP.
277 *
278 * NB: null pointer to avoid free at
279 * done: below.
280 */
281 KEY_FREESP(sp), *sp = NULL;
282 goto done;
283 }
284 }
285
286 /*
287 * Do delayed checksums now because we send before
288 * this is done in the normal processing path.
289 * For IPv6 we do delayed checksums in ip6_output.c.
290 */
291#ifdef INET
292 if ((*m)->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
293 ipseclog((LOG_DEBUG,
294 "%s: we do not support IPv4 over IPv6", __func__));
295 in_delayed_cksum(*m);
296 (*m)->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
297 }
298#endif
299
300 /*
301 * Preserve KAME behaviour: ENOENT can be returned
302 * when an SA acquire is in progress. Don't propagate
303 * this to user-level; it confuses applications.
304 *
305 * XXX this will go away when the SADB is redone.
306 */
307 if (*error == ENOENT)
308 *error = 0;
309 goto do_ipsec;
310 } else { /* sp == NULL */
311 if (*error != 0) {
312 /*
313 * Hack: -EINVAL is used to signal that a packet
314 * should be silently discarded. This is typically
315 * because we asked key management for an SA and
316 * it was delayed (e.g. kicked up to IKE).
317 */
318 if (*error == -EINVAL)
319 *error = 0;
320 goto bad;
321 } else {
322 /* No IPsec processing for this packet. */
323 }
324 }
325done:
326 return 0;
327do_ipsec:
328 return -1;
329bad:
330 return 1;
331#endif /* IPSEC */
332 return 0;
333}
334
335#if 0
336/*
337 * Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
338 * Called from ip_forward().
339 * Returns MTU suggestion for ICMP needfrag reply.
340 */
341int
342ip6_ipsec_mtu(struct mbuf *m)
343{
344 int mtu = 0;
345 /*
346 * If the packet is routed over IPsec tunnel, tell the
347 * originator the tunnel MTU.
348 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
349 * XXX quickhack!!!
350 */
351#ifdef IPSEC
352 struct secpolicy *sp = NULL;
353 int ipsecerror;
354 int ipsechdr;
355 struct route *ro;
356 sp = ipsec_getpolicybyaddr(m,
357 IPSEC_DIR_OUTBOUND,
358 IP_FORWARDING,
359 &ipsecerror);
360 if (sp != NULL) {
361 /* count IPsec header size */
362 ipsechdr = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, NULL);
363
364 /*
365 * find the correct route for outer IPv4
366 * header, compute tunnel MTU.
367 */
368 if (sp->req != NULL &&
369 sp->req->sav != NULL &&
370 sp->req->sav->sah != NULL) {
371 ro = &sp->req->sav->sah->route_cache.sa_route;
372 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
373 mtu = ro->ro_rt->rt_mtu ? ro->ro_rt->rt_mtu :
374 ro->ro_rt->rt_ifp->if_mtu;
375 mtu -= ipsechdr;
376 }
377 }
378 KEY_FREESP(&sp);
379 }
380#endif /* IPSEC */
381 /* XXX else case missing. */
382 return mtu;
383}
384#endif