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30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
33 #include "opt_ipsec.h"
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
39 #include <sys/malloc.h>
41 #include <sys/protosw.h>
42 #include <sys/socket.h>
43 #include <sys/socketvar.h>
44 #include <sys/sysctl.h>
47 #include <net/route.h>
49 #include <netinet/in.h>
50 #include <netinet/in_systm.h>
51 #include <netinet/in_var.h>
52 #include <netinet/ip.h>
53 #include <netinet/in_pcb.h>
54 #include <netinet/ip_var.h>
55 #include <netinet/ip_options.h>
57 #include <machine/in_cksum.h>
60 #include <netipsec/ipsec.h>
61 #include <netipsec/ipsec6.h>
62 #include <netipsec/xform.h>
63 #include <netipsec/key.h>
65 #include <netipsec/key_debug.h>
67 #define KEYDEBUG(lev,arg)
71 #include <netinet6/ip6_ipsec.h>
72 #include <netinet6/ip6_var.h>
74 extern struct protosw inet6sw[];
77 * Check if we have to jump over firewall processing for this packet.
78 * Called from ip_input().
79 * 1 = jump over firewall, 0 = packet goes through firewall.
82 ip6_ipsec_filtertunnel(struct mbuf *m)
84 #if defined(IPSEC) && !defined(IPSEC_FILTERTUNNEL)
86 * Bypass packet filtering for packets from a tunnel.
88 if (m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL) != NULL)
95 * Check if this packet has an active SA and needs to be dropped instead
97 * Called from ip_input().
98 * 1 = drop packet, 0 = forward packet.
101 ip6_ipsec_fwd(struct mbuf *m)
105 struct tdb_ident *tdbi;
106 struct secpolicy *sp;
108 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
111 tdbi = (struct tdb_ident *)(mtag + 1);
112 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
114 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
115 IP_FORWARDING, &error);
117 if (sp == NULL) { /* NB: can happen if error */
119 /*XXX error stat???*/
120 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/
125 * Check security policy against packet attributes.
127 error = ipsec_in_reject(sp, m);
131 ip6stat.ip6s_cantforward++;
139 * Check if protocol type doesn't have a further header and do IPSEC
140 * decryption or reject right now. Protocols with further headers get
141 * their IPSEC treatment within the protocol specific processing.
142 * Called from ip_input().
143 * 1 = drop packet, 0 = continue processing packet.
146 ip6_ipsec_input(struct mbuf *m, int nxt)
150 struct tdb_ident *tdbi;
151 struct secpolicy *sp;
154 * enforce IPsec policy checking if we are seeing last header.
155 * note that we do not visit this with protocols with pcb layer
156 * code - like udp/tcp/raw ip.
158 if ((inet6sw[ip6_protox[nxt]].pr_flags & PR_LASTHDR) != 0 &&
159 ipsec6_in_reject(m, NULL)) {
162 * Check if the packet has already had IPsec processing
163 * done. If so, then just pass it along. This tag gets
164 * set during AH, ESP, etc. input handling, before the
165 * packet is returned to the ip input queue for delivery.
167 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL);
170 tdbi = (struct tdb_ident *)(mtag + 1);
171 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND);
173 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND,
174 IP_FORWARDING, &error);
178 * Check security policy against packet attributes.
180 error = ipsec_in_reject(sp, m);
183 /* XXX error stat??? */
185 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/
197 * Called from ip6_output().
198 * 1 = drop packet, 0 = continue processing packet,
199 * -1 = packet was reinjected and stop processing packet
203 ip6_ipsec_output(struct mbuf **m, struct inpcb *inp, int *flags, int *error,
204 struct ifnet **ifp, struct secpolicy **sp)
207 struct tdb_ident *tdbi;
212 mtag = m_tag_find(*m, PACKET_TAG_IPSEC_PENDING_TDB, NULL);
214 tdbi = (struct tdb_ident *)(mtag + 1);
215 *sp = ipsec_getpolicy(tdbi, IPSEC_DIR_OUTBOUND);
217 *error = -EINVAL; /* force silent drop */
218 m_tag_delete(*m, mtag);
220 *sp = ipsec4_checkpolicy(*m, IPSEC_DIR_OUTBOUND, *flags,
225 * There are four return cases:
226 * sp != NULL apply IPsec policy
227 * sp == NULL, error == 0 no IPsec handling needed
228 * sp == NULL, error == -EINVAL discard packet w/o error
229 * sp == NULL, error != 0 discard packet, report error
232 /* Loop detection, check if ipsec processing already done */
233 KASSERT((*sp)->req != NULL, ("ip_output: no ipsec request"));
234 for (mtag = m_tag_first(*m); mtag != NULL;
235 mtag = m_tag_next(*m, mtag)) {
236 if (mtag->m_tag_cookie != MTAG_ABI_COMPAT)
238 if (mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_DONE &&
239 mtag->m_tag_id != PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED)
242 * Check if policy has an SA associated with it.
243 * This can happen when an SP has yet to acquire
244 * an SA; e.g. on first reference. If it occurs,
245 * then we let ipsec4_process_packet do its thing.
247 if ((*sp)->req->sav == NULL)
249 tdbi = (struct tdb_ident *)(mtag + 1);
250 if (tdbi->spi == (*sp)->req->sav->spi &&
251 tdbi->proto == (*sp)->req->sav->sah->saidx.proto &&
252 bcmp(&tdbi->dst, &(*sp)->req->sav->sah->saidx.dst,
253 sizeof (union sockaddr_union)) == 0) {
255 * No IPsec processing is needed, free
258 * NB: null pointer to avoid free at
261 KEY_FREESP(sp), *sp = NULL;
268 * Do delayed checksums now because we send before
269 * this is done in the normal processing path.
271 if ((*m)->m_pkthdr.csum_flags & CSUM_DELAY_DATA) {
272 in_delayed_cksum(*m);
273 (*m)->m_pkthdr.csum_flags &= ~CSUM_DELAY_DATA;
277 * Preserve KAME behaviour: ENOENT can be returned
278 * when an SA acquire is in progress. Don't propagate
279 * this to user-level; it confuses applications.
281 * XXX this will go away when the SADB is redone.
283 if (*error == ENOENT)
286 } else { /* sp == NULL */
289 * Hack: -EINVAL is used to signal that a packet
290 * should be silently discarded. This is typically
291 * because we asked key management for an SA and
292 * it was delayed (e.g. kicked up to IKE).
294 if (*error == -EINVAL)
298 /* No IPsec processing for this packet. */
313 * Compute the MTU for a forwarded packet that gets IPSEC encapsulated.
314 * Called from ip_forward().
315 * Returns MTU suggestion for ICMP needfrag reply.
318 ip6_ipsec_mtu(struct mbuf *m)
322 * If the packet is routed over IPsec tunnel, tell the
323 * originator the tunnel MTU.
324 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz
328 struct secpolicy *sp = NULL;
332 sp = ipsec_getpolicybyaddr(m,
337 /* count IPsec header size */
338 ipsechdr = ipsec4_hdrsiz(m,
343 * find the correct route for outer IPv4
344 * header, compute tunnel MTU.
346 if (sp->req != NULL &&
347 sp->req->sav != NULL &&
348 sp->req->sav->sah != NULL) {
349 ro = &sp->req->sav->sah->sa_route;
350 if (ro->ro_rt && ro->ro_rt->rt_ifp) {
352 ro->ro_rt->rt_rmx.rmx_mtu ?
353 ro->ro_rt->rt_rmx.rmx_mtu :
354 ro->ro_rt->rt_ifp->if_mtu;
361 /* XXX else case missing. */