1 /* $FreeBSD: stable/9/sys/netipsec/ipsec.c 299628 2016-05-13 08:51:51Z ngie $ */
2 /* $KAME: ipsec.c,v 1.103 2001/05/24 07:14:18 sakane Exp $ */
3
4 /*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /*
34 * IPsec controller part.
35 */
36
37 #include "opt_inet.h"
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/malloc.h>
44 #include <sys/mbuf.h>
45 #include <sys/domain.h>
46 #include <sys/priv.h>
47 #include <sys/protosw.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/errno.h>
51 #include <sys/time.h>
52 #include <sys/kernel.h>
53 #include <sys/syslog.h>
54 #include <sys/sysctl.h>
55 #include <sys/proc.h>
56
57 #include <net/if.h>
58 #include <net/route.h>
59 #include <net/vnet.h>
60
61 #include <netinet/in.h>
62 #include <netinet/in_systm.h>
63 #include <netinet/ip.h>
64 #include <netinet/ip_var.h>
65 #include <netinet/in_var.h>
66 #include <netinet/udp.h>
67 #include <netinet/udp_var.h>
68 #include <netinet/tcp.h>
69 #include <netinet/udp.h>
70
71 #include <netinet/ip6.h>
72 #ifdef INET6
73 #include <netinet6/ip6_var.h>
74 #endif
75 #include <netinet/in_pcb.h>
76 #ifdef INET6
77 #include <netinet/icmp6.h>
78 #endif
79
80 #include <sys/types.h>
81 #include <netipsec/ipsec.h>
82 #ifdef INET6
83 #include <netipsec/ipsec6.h>
84 #endif
85 #include <netipsec/ah_var.h>
86 #include <netipsec/esp_var.h>
87 #include <netipsec/ipcomp.h> /*XXX*/
88 #include <netipsec/ipcomp_var.h>
89
90 #include <netipsec/key.h>
91 #include <netipsec/keydb.h>
92 #include <netipsec/key_debug.h>
93
94 #include <netipsec/xform.h>
95
96 #include <machine/in_cksum.h>
97
98 #include <opencrypto/cryptodev.h>
99
100 #ifdef IPSEC_DEBUG
101 VNET_DEFINE(int, ipsec_debug) = 1;
102 #else
103 VNET_DEFINE(int, ipsec_debug) = 0;
104 #endif
105
106 /* NB: name changed so netstat doesn't use it. */
107 VNET_DEFINE(struct ipsecstat, ipsec4stat);
108 VNET_DEFINE(int, ip4_ah_offsetmask) = 0; /* maybe IP_DF? */
109 /* DF bit on encap. 0: clear 1: set 2: copy */
110 VNET_DEFINE(int, ip4_ipsec_dfbit) = 0;
111 VNET_DEFINE(int, ip4_esp_trans_deflev) = IPSEC_LEVEL_USE;
112 VNET_DEFINE(int, ip4_esp_net_deflev) = IPSEC_LEVEL_USE;
113 VNET_DEFINE(int, ip4_ah_trans_deflev) = IPSEC_LEVEL_USE;
114 VNET_DEFINE(int, ip4_ah_net_deflev) = IPSEC_LEVEL_USE;
115 VNET_DEFINE(struct secpolicy, ip4_def_policy);
116 /* ECN ignore(-1)/forbidden(0)/allowed(1) */
117 VNET_DEFINE(int, ip4_ipsec_ecn) = 0;
118 VNET_DEFINE(int, ip4_esp_randpad) = -1;
119
120 /*
121 * Crypto support requirements:
122 *
123 * 1 require hardware support
124 * -1 require software support
125 * 0 take anything
126 */
127 VNET_DEFINE(int, crypto_support) = CRYPTOCAP_F_HARDWARE | CRYPTOCAP_F_SOFTWARE;
128
129 FEATURE(ipsec, "Internet Protocol Security (IPsec)");
130 #ifdef IPSEC_NAT_T
131 FEATURE(ipsec_natt, "UDP Encapsulation of IPsec ESP Packets ('NAT-T')");
132 #endif
133
134 SYSCTL_DECL(_net_inet_ipsec);
135
136 /* net.inet.ipsec */
137 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_POLICY, def_policy,
138 CTLFLAG_RW, &VNET_NAME(ip4_def_policy).policy, 0,
139 "IPsec default policy.");
140 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_TRANSLEV, esp_trans_deflev,
141 CTLFLAG_RW, &VNET_NAME(ip4_esp_trans_deflev), 0,
142 "Default ESP transport mode level");
143 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_ESP_NETLEV, esp_net_deflev,
144 CTLFLAG_RW, &VNET_NAME(ip4_esp_net_deflev), 0,
145 "Default ESP tunnel mode level.");
146 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_TRANSLEV, ah_trans_deflev,
147 CTLFLAG_RW, &VNET_NAME(ip4_ah_trans_deflev), 0,
148 "AH transfer mode default level.");
149 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEF_AH_NETLEV, ah_net_deflev,
150 CTLFLAG_RW, &VNET_NAME(ip4_ah_net_deflev), 0,
151 "AH tunnel mode default level.");
152 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_CLEARTOS, ah_cleartos,
153 CTLFLAG_RW, &VNET_NAME(ah_cleartos), 0,
154 "If set clear type-of-service field when doing AH computation.");
155 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_AH_OFFSETMASK, ah_offsetmask,
156 CTLFLAG_RW, &VNET_NAME(ip4_ah_offsetmask), 0,
157 "If not set clear offset field mask when doing AH computation.");
158 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DFBIT, dfbit,
159 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_dfbit), 0,
160 "Do not fragment bit on encap.");
161 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_ECN, ecn,
162 CTLFLAG_RW, &VNET_NAME(ip4_ipsec_ecn), 0,
163 "Explicit Congestion Notification handling.");
164 SYSCTL_VNET_INT(_net_inet_ipsec, IPSECCTL_DEBUG, debug,
165 CTLFLAG_RW, &VNET_NAME(ipsec_debug), 0,
166 "Enable IPsec debugging output when set.");
167 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, crypto_support,
168 CTLFLAG_RW, &VNET_NAME(crypto_support), 0,
169 "Crypto driver selection.");
170 SYSCTL_VNET_STRUCT(_net_inet_ipsec, OID_AUTO, ipsecstats,
171 CTLFLAG_RD, &VNET_NAME(ipsec4stat), ipsecstat,
172 "IPsec IPv4 statistics.");
173
174 #ifdef REGRESSION
175 /*
176 * When set to 1, IPsec will send packets with the same sequence number.
177 * This allows to verify if the other side has proper replay attacks detection.
178 */
179 VNET_DEFINE(int, ipsec_replay) = 0;
180 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_replay,
181 CTLFLAG_RW, &VNET_NAME(ipsec_replay), 0,
182 "Emulate replay attack");
183 /*
184 * When set 1, IPsec will send packets with corrupted HMAC.
185 * This allows to verify if the other side properly detects modified packets.
186 */
187 VNET_DEFINE(int, ipsec_integrity) = 0;
188 SYSCTL_VNET_INT(_net_inet_ipsec, OID_AUTO, test_integrity,
189 CTLFLAG_RW, &VNET_NAME(ipsec_integrity), 0,
190 "Emulate man-in-the-middle attack");
191 #endif
192
193 #ifdef INET6
194 VNET_DEFINE(struct ipsecstat, ipsec6stat);
195 VNET_DEFINE(int, ip6_esp_trans_deflev) = IPSEC_LEVEL_USE;
196 VNET_DEFINE(int, ip6_esp_net_deflev) = IPSEC_LEVEL_USE;
197 VNET_DEFINE(int, ip6_ah_trans_deflev) = IPSEC_LEVEL_USE;
198 VNET_DEFINE(int, ip6_ah_net_deflev) = IPSEC_LEVEL_USE;
199 VNET_DEFINE(int, ip6_ipsec_ecn) = 0; /* ECN ignore(-1)/forbidden(0)/allowed(1) */
200
201 SYSCTL_DECL(_net_inet6_ipsec6);
202
203 /* net.inet6.ipsec6 */
204 #ifdef COMPAT_KAME
205 SYSCTL_OID(_net_inet6_ipsec6, IPSECCTL_STATS, stats, CTLFLAG_RD,
206 0, 0, compat_ipsecstats_sysctl, "S", "IPsec IPv6 statistics.");
207 #endif /* COMPAT_KAME */
208 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_POLICY, def_policy, CTLFLAG_RW,
209 &VNET_NAME(ip4_def_policy).policy, 0,
210 "IPsec default policy.");
211 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_TRANSLEV,
212 esp_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_trans_deflev), 0,
213 "Default ESP transport mode level.");
214 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_ESP_NETLEV,
215 esp_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_esp_net_deflev), 0,
216 "Default ESP tunnel mode level.");
217 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_TRANSLEV,
218 ah_trans_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_trans_deflev), 0,
219 "AH transfer mode default level.");
220 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEF_AH_NETLEV,
221 ah_net_deflev, CTLFLAG_RW, &VNET_NAME(ip6_ah_net_deflev), 0,
222 "AH tunnel mode default level.");
223 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_ECN,
224 ecn, CTLFLAG_RW, &VNET_NAME(ip6_ipsec_ecn), 0,
225 "Explicit Congestion Notification handling.");
226 SYSCTL_VNET_INT(_net_inet6_ipsec6, IPSECCTL_DEBUG, debug, CTLFLAG_RW,
227 &VNET_NAME(ipsec_debug), 0,
228 "Enable IPsec debugging output when set.");
229 SYSCTL_VNET_STRUCT(_net_inet6_ipsec6, IPSECCTL_STATS,
230 ipsecstats, CTLFLAG_RD, &VNET_NAME(ipsec6stat), ipsecstat,
231 "IPsec IPv6 statistics.");
232 #endif /* INET6 */
233
234 static int ipsec_setspidx_inpcb __P((struct mbuf *, struct inpcb *));
235 static int ipsec_setspidx __P((struct mbuf *, struct secpolicyindex *, int));
236 static void ipsec4_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
237 static int ipsec4_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
238 #ifdef INET6
239 static void ipsec6_get_ulp __P((struct mbuf *m, struct secpolicyindex *, int));
240 static int ipsec6_setspidx_ipaddr __P((struct mbuf *, struct secpolicyindex *));
241 #endif
242 static void ipsec_delpcbpolicy __P((struct inpcbpolicy *));
243 static struct secpolicy *ipsec_deepcopy_policy __P((struct secpolicy *src));
244 static void vshiftl __P((unsigned char *, int, int));
245
246 MALLOC_DEFINE(M_IPSEC_INPCB, "inpcbpolicy", "inpcb-resident ipsec policy");
247
248 /*
249 * Return a held reference to the default SP.
250 */
251 static struct secpolicy *
key_allocsp_default(const char * where,int tag)252 key_allocsp_default(const char* where, int tag)
253 {
254 struct secpolicy *sp;
255
256 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
257 printf("DP key_allocsp_default from %s:%u\n", where, tag));
258
259 sp = &V_ip4_def_policy;
260 if (sp->policy != IPSEC_POLICY_DISCARD &&
261 sp->policy != IPSEC_POLICY_NONE) {
262 ipseclog((LOG_INFO, "fixed system default policy: %d->%d\n",
263 sp->policy, IPSEC_POLICY_NONE));
264 sp->policy = IPSEC_POLICY_NONE;
265 }
266 key_addref(sp);
267
268 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
269 printf("DP key_allocsp_default returns SP:%p (%u)\n",
270 sp, sp->refcnt));
271 return (sp);
272 }
273 #define KEY_ALLOCSP_DEFAULT() \
274 key_allocsp_default(__FILE__, __LINE__)
275
276 /*
277 * For OUTBOUND packet having a socket. Searching SPD for packet,
278 * and return a pointer to SP.
279 * OUT: NULL: no apropreate SP found, the following value is set to error.
280 * 0 : bypass
281 * EACCES : discard packet.
282 * ENOENT : ipsec_acquire() in progress, maybe.
283 * others : error occured.
284 * others: a pointer to SP
285 *
286 * NOTE: IPv6 mapped adddress concern is implemented here.
287 */
288 struct secpolicy *
ipsec_getpolicy(struct tdb_ident * tdbi,u_int dir)289 ipsec_getpolicy(struct tdb_ident *tdbi, u_int dir)
290 {
291 struct secpolicy *sp;
292
293 IPSEC_ASSERT(tdbi != NULL, ("null tdbi"));
294 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
295 ("invalid direction %u", dir));
296
297 sp = KEY_ALLOCSP2(tdbi->spi, &tdbi->dst, tdbi->proto, dir);
298 if (sp == NULL) /*XXX????*/
299 sp = KEY_ALLOCSP_DEFAULT();
300 IPSEC_ASSERT(sp != NULL, ("null SP"));
301 return (sp);
302 }
303
304 /*
305 * For OUTBOUND packet having a socket. Searching SPD for packet,
306 * and return a pointer to SP.
307 * OUT: NULL: no apropreate SP found, the following value is set to error.
308 * 0 : bypass
309 * EACCES : discard packet.
310 * ENOENT : ipsec_acquire() in progress, maybe.
311 * others : error occured.
312 * others: a pointer to SP
313 *
314 * NOTE: IPv6 mapped adddress concern is implemented here.
315 */
316 static struct secpolicy *
ipsec_getpolicybysock(struct mbuf * m,u_int dir,struct inpcb * inp,int * error)317 ipsec_getpolicybysock(struct mbuf *m, u_int dir, struct inpcb *inp, int *error)
318 {
319 struct inpcbpolicy *pcbsp;
320 struct secpolicy *currsp = NULL; /* Policy on socket. */
321 struct secpolicy *sp;
322
323 IPSEC_ASSERT(m != NULL, ("null mbuf"));
324 IPSEC_ASSERT(inp != NULL, ("null inpcb"));
325 IPSEC_ASSERT(error != NULL, ("null error"));
326 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
327 ("invalid direction %u", dir));
328
329 /* Set spidx in pcb. */
330 *error = ipsec_setspidx_inpcb(m, inp);
331 if (*error)
332 return (NULL);
333
334 pcbsp = inp->inp_sp;
335 IPSEC_ASSERT(pcbsp != NULL, ("null pcbsp"));
336 switch (dir) {
337 case IPSEC_DIR_INBOUND:
338 currsp = pcbsp->sp_in;
339 break;
340 case IPSEC_DIR_OUTBOUND:
341 currsp = pcbsp->sp_out;
342 break;
343 }
344 IPSEC_ASSERT(currsp != NULL, ("null currsp"));
345
346 if (pcbsp->priv) { /* When privilieged socket. */
347 switch (currsp->policy) {
348 case IPSEC_POLICY_BYPASS:
349 case IPSEC_POLICY_IPSEC:
350 key_addref(currsp);
351 sp = currsp;
352 break;
353
354 case IPSEC_POLICY_ENTRUST:
355 /* Look for a policy in SPD. */
356 sp = KEY_ALLOCSP(&currsp->spidx, dir);
357 if (sp == NULL) /* No SP found. */
358 sp = KEY_ALLOCSP_DEFAULT();
359 break;
360
361 default:
362 ipseclog((LOG_ERR, "%s: Invalid policy for PCB %d\n",
363 __func__, currsp->policy));
364 *error = EINVAL;
365 return (NULL);
366 }
367 } else { /* Unpriv, SPD has policy. */
368 sp = KEY_ALLOCSP(&currsp->spidx, dir);
369 if (sp == NULL) { /* No SP found. */
370 switch (currsp->policy) {
371 case IPSEC_POLICY_BYPASS:
372 ipseclog((LOG_ERR, "%s: Illegal policy for "
373 "non-priviliged defined %d\n",
374 __func__, currsp->policy));
375 *error = EINVAL;
376 return (NULL);
377
378 case IPSEC_POLICY_ENTRUST:
379 sp = KEY_ALLOCSP_DEFAULT();
380 break;
381
382 case IPSEC_POLICY_IPSEC:
383 key_addref(currsp);
384 sp = currsp;
385 break;
386
387 default:
388 ipseclog((LOG_ERR, "%s: Invalid policy for "
389 "PCB %d\n", __func__, currsp->policy));
390 *error = EINVAL;
391 return (NULL);
392 }
393 }
394 }
395 IPSEC_ASSERT(sp != NULL,
396 ("null SP (priv %u policy %u", pcbsp->priv, currsp->policy));
397 KEYDEBUG(KEYDEBUG_IPSEC_STAMP,
398 printf("DP %s (priv %u policy %u) allocate SP:%p (refcnt %u)\n",
399 __func__, pcbsp->priv, currsp->policy, sp, sp->refcnt));
400 return (sp);
401 }
402
403 /*
404 * For FORWADING packet or OUTBOUND without a socket. Searching SPD for packet,
405 * and return a pointer to SP.
406 * OUT: positive: a pointer to the entry for security policy leaf matched.
407 * NULL: no apropreate SP found, the following value is set to error.
408 * 0 : bypass
409 * EACCES : discard packet.
410 * ENOENT : ipsec_acquire() in progress, maybe.
411 * others : error occured.
412 */
413 struct secpolicy *
ipsec_getpolicybyaddr(struct mbuf * m,u_int dir,int flag,int * error)414 ipsec_getpolicybyaddr(struct mbuf *m, u_int dir, int flag, int *error)
415 {
416 struct secpolicyindex spidx;
417 struct secpolicy *sp;
418
419 IPSEC_ASSERT(m != NULL, ("null mbuf"));
420 IPSEC_ASSERT(error != NULL, ("null error"));
421 IPSEC_ASSERT(dir == IPSEC_DIR_INBOUND || dir == IPSEC_DIR_OUTBOUND,
422 ("invalid direction %u", dir));
423
424 sp = NULL;
425 if (key_havesp(dir)) {
426 /* Make an index to look for a policy. */
427 *error = ipsec_setspidx(m, &spidx,
428 (flag & IP_FORWARDING) ? 0 : 1);
429 if (*error != 0) {
430 DPRINTF(("%s: setpidx failed, dir %u flag %u\n",
431 __func__, dir, flag));
432 return (NULL);
433 }
434 spidx.dir = dir;
435
436 sp = KEY_ALLOCSP(&spidx, dir);
437 }
438 if (sp == NULL) /* No SP found, use system default. */
439 sp = KEY_ALLOCSP_DEFAULT();
440 IPSEC_ASSERT(sp != NULL, ("null SP"));
441 return (sp);
442 }
443
444 struct secpolicy *
ipsec4_checkpolicy(struct mbuf * m,u_int dir,u_int flag,int * error,struct inpcb * inp)445 ipsec4_checkpolicy(struct mbuf *m, u_int dir, u_int flag, int *error,
446 struct inpcb *inp)
447 {
448 struct secpolicy *sp;
449
450 *error = 0;
451 if (inp == NULL)
452 sp = ipsec_getpolicybyaddr(m, dir, flag, error);
453 else
454 sp = ipsec_getpolicybysock(m, dir, inp, error);
455 if (sp == NULL) {
456 IPSEC_ASSERT(*error != 0, ("getpolicy failed w/o error"));
457 IPSECSTAT_INC(ips_out_inval);
458 return (NULL);
459 }
460 IPSEC_ASSERT(*error == 0, ("sp w/ error set to %u", *error));
461 switch (sp->policy) {
462 case IPSEC_POLICY_ENTRUST:
463 default:
464 printf("%s: invalid policy %u\n", __func__, sp->policy);
465 /* FALLTHROUGH */
466 case IPSEC_POLICY_DISCARD:
467 IPSECSTAT_INC(ips_out_polvio);
468 *error = -EINVAL; /* Packet is discarded by caller. */
469 break;
470 case IPSEC_POLICY_BYPASS:
471 case IPSEC_POLICY_NONE:
472 KEY_FREESP(&sp);
473 sp = NULL; /* NB: force NULL result. */
474 break;
475 case IPSEC_POLICY_IPSEC:
476 if (sp->req == NULL) /* Acquire a SA. */
477 *error = key_spdacquire(sp);
478 break;
479 }
480 if (*error != 0) {
481 KEY_FREESP(&sp);
482 sp = NULL;
483 }
484 return (sp);
485 }
486
487 static int
ipsec_setspidx_inpcb(struct mbuf * m,struct inpcb * inp)488 ipsec_setspidx_inpcb(struct mbuf *m, struct inpcb *inp)
489 {
490 int error;
491
492 IPSEC_ASSERT(inp != NULL, ("null inp"));
493 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
494 IPSEC_ASSERT(inp->inp_sp->sp_out != NULL && inp->inp_sp->sp_in != NULL,
495 ("null sp_in || sp_out"));
496
497 error = ipsec_setspidx(m, &inp->inp_sp->sp_in->spidx, 1);
498 if (error == 0) {
499 inp->inp_sp->sp_in->spidx.dir = IPSEC_DIR_INBOUND;
500 inp->inp_sp->sp_out->spidx = inp->inp_sp->sp_in->spidx;
501 inp->inp_sp->sp_out->spidx.dir = IPSEC_DIR_OUTBOUND;
502 } else {
503 bzero(&inp->inp_sp->sp_in->spidx,
504 sizeof (inp->inp_sp->sp_in->spidx));
505 bzero(&inp->inp_sp->sp_out->spidx,
506 sizeof (inp->inp_sp->sp_in->spidx));
507 }
508 return (error);
509 }
510
511 /*
512 * Configure security policy index (src/dst/proto/sport/dport)
513 * by looking at the content of mbuf.
514 * The caller is responsible for error recovery (like clearing up spidx).
515 */
516 static int
ipsec_setspidx(struct mbuf * m,struct secpolicyindex * spidx,int needport)517 ipsec_setspidx(struct mbuf *m, struct secpolicyindex *spidx, int needport)
518 {
519 struct ip *ip = NULL;
520 struct ip ipbuf;
521 u_int v;
522 struct mbuf *n;
523 int len;
524 int error;
525
526 IPSEC_ASSERT(m != NULL, ("null mbuf"));
527
528 /*
529 * Validate m->m_pkthdr.len. We see incorrect length if we
530 * mistakenly call this function with inconsistent mbuf chain
531 * (like 4.4BSD tcp/udp processing). XXX Should we panic here?
532 */
533 len = 0;
534 for (n = m; n; n = n->m_next)
535 len += n->m_len;
536 if (m->m_pkthdr.len != len) {
537 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
538 printf("%s: pkthdr len(%d) mismatch (%d), ignored.\n",
539 __func__, len, m->m_pkthdr.len));
540 return (EINVAL);
541 }
542
543 if (m->m_pkthdr.len < sizeof(struct ip)) {
544 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
545 printf("%s: pkthdr len(%d) too small (v4), ignored.\n",
546 __func__, m->m_pkthdr.len));
547 return (EINVAL);
548 }
549
550 if (m->m_len >= sizeof(*ip))
551 ip = mtod(m, struct ip *);
552 else {
553 m_copydata(m, 0, sizeof(ipbuf), (caddr_t)&ipbuf);
554 ip = &ipbuf;
555 }
556 v = ip->ip_v;
557 switch (v) {
558 case 4:
559 error = ipsec4_setspidx_ipaddr(m, spidx);
560 if (error)
561 return (error);
562 ipsec4_get_ulp(m, spidx, needport);
563 return (0);
564 #ifdef INET6
565 case 6:
566 if (m->m_pkthdr.len < sizeof(struct ip6_hdr)) {
567 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
568 printf("%s: pkthdr len(%d) too small (v6), "
569 "ignored\n", __func__, m->m_pkthdr.len));
570 return (EINVAL);
571 }
572 error = ipsec6_setspidx_ipaddr(m, spidx);
573 if (error)
574 return (error);
575 ipsec6_get_ulp(m, spidx, needport);
576 return (0);
577 #endif
578 default:
579 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
580 printf("%s: " "unknown IP version %u, ignored.\n",
581 __func__, v));
582 return (EINVAL);
583 }
584 }
585
586 static void
ipsec4_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)587 ipsec4_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
588 {
589 u_int8_t nxt;
590 int off;
591
592 /* Sanity check. */
593 IPSEC_ASSERT(m != NULL, ("null mbuf"));
594 IPSEC_ASSERT(m->m_pkthdr.len >= sizeof(struct ip),("packet too short"));
595
596 /* NB: ip_input() flips it into host endian. XXX Need more checking. */
597 if (m->m_len >= sizeof (struct ip)) {
598 struct ip *ip = mtod(m, struct ip *);
599 if (ip->ip_off & (IP_MF | IP_OFFMASK))
600 goto done;
601 off = ip->ip_hl << 2;
602 nxt = ip->ip_p;
603 } else {
604 struct ip ih;
605
606 m_copydata(m, 0, sizeof (struct ip), (caddr_t) &ih);
607 if (ih.ip_off & (IP_MF | IP_OFFMASK))
608 goto done;
609 off = ih.ip_hl << 2;
610 nxt = ih.ip_p;
611 }
612
613 while (off < m->m_pkthdr.len) {
614 struct ip6_ext ip6e;
615 struct tcphdr th;
616 struct udphdr uh;
617
618 switch (nxt) {
619 case IPPROTO_TCP:
620 spidx->ul_proto = nxt;
621 if (!needport)
622 goto done_proto;
623 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
624 goto done;
625 m_copydata(m, off, sizeof (th), (caddr_t) &th);
626 spidx->src.sin.sin_port = th.th_sport;
627 spidx->dst.sin.sin_port = th.th_dport;
628 return;
629 case IPPROTO_UDP:
630 spidx->ul_proto = nxt;
631 if (!needport)
632 goto done_proto;
633 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
634 goto done;
635 m_copydata(m, off, sizeof (uh), (caddr_t) &uh);
636 spidx->src.sin.sin_port = uh.uh_sport;
637 spidx->dst.sin.sin_port = uh.uh_dport;
638 return;
639 case IPPROTO_AH:
640 if (off + sizeof(ip6e) > m->m_pkthdr.len)
641 goto done;
642 /* XXX Sigh, this works but is totally bogus. */
643 m_copydata(m, off, sizeof(ip6e), (caddr_t) &ip6e);
644 off += (ip6e.ip6e_len + 2) << 2;
645 nxt = ip6e.ip6e_nxt;
646 break;
647 case IPPROTO_ICMP:
648 default:
649 /* XXX Intermediate headers??? */
650 spidx->ul_proto = nxt;
651 goto done_proto;
652 }
653 }
654 done:
655 spidx->ul_proto = IPSEC_ULPROTO_ANY;
656 done_proto:
657 spidx->src.sin.sin_port = IPSEC_PORT_ANY;
658 spidx->dst.sin.sin_port = IPSEC_PORT_ANY;
659 }
660
661 /* Assumes that m is sane. */
662 static int
ipsec4_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)663 ipsec4_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
664 {
665 static const struct sockaddr_in template = {
666 sizeof (struct sockaddr_in),
667 AF_INET,
668 0, { 0 }, { 0, 0, 0, 0, 0, 0, 0, 0 }
669 };
670
671 spidx->src.sin = template;
672 spidx->dst.sin = template;
673
674 if (m->m_len < sizeof (struct ip)) {
675 m_copydata(m, offsetof(struct ip, ip_src),
676 sizeof (struct in_addr),
677 (caddr_t) &spidx->src.sin.sin_addr);
678 m_copydata(m, offsetof(struct ip, ip_dst),
679 sizeof (struct in_addr),
680 (caddr_t) &spidx->dst.sin.sin_addr);
681 } else {
682 struct ip *ip = mtod(m, struct ip *);
683 spidx->src.sin.sin_addr = ip->ip_src;
684 spidx->dst.sin.sin_addr = ip->ip_dst;
685 }
686
687 spidx->prefs = sizeof(struct in_addr) << 3;
688 spidx->prefd = sizeof(struct in_addr) << 3;
689
690 return (0);
691 }
692
693 #ifdef INET6
694 static void
ipsec6_get_ulp(struct mbuf * m,struct secpolicyindex * spidx,int needport)695 ipsec6_get_ulp(struct mbuf *m, struct secpolicyindex *spidx, int needport)
696 {
697 int off, nxt;
698 struct tcphdr th;
699 struct udphdr uh;
700 struct icmp6_hdr ih;
701
702 /* Sanity check. */
703 if (m == NULL)
704 panic("%s: NULL pointer was passed.\n", __func__);
705
706 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
707 printf("%s:\n", __func__); kdebug_mbuf(m));
708
709 /* Set default. */
710 spidx->ul_proto = IPSEC_ULPROTO_ANY;
711 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = IPSEC_PORT_ANY;
712 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = IPSEC_PORT_ANY;
713
714 nxt = -1;
715 off = ip6_lasthdr(m, 0, IPPROTO_IPV6, &nxt);
716 if (off < 0 || m->m_pkthdr.len < off)
717 return;
718
719 switch (nxt) {
720 case IPPROTO_TCP:
721 spidx->ul_proto = nxt;
722 if (!needport)
723 break;
724 if (off + sizeof(struct tcphdr) > m->m_pkthdr.len)
725 break;
726 m_copydata(m, off, sizeof(th), (caddr_t)&th);
727 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = th.th_sport;
728 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = th.th_dport;
729 break;
730 case IPPROTO_UDP:
731 spidx->ul_proto = nxt;
732 if (!needport)
733 break;
734 if (off + sizeof(struct udphdr) > m->m_pkthdr.len)
735 break;
736 m_copydata(m, off, sizeof(uh), (caddr_t)&uh);
737 ((struct sockaddr_in6 *)&spidx->src)->sin6_port = uh.uh_sport;
738 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port = uh.uh_dport;
739 break;
740 case IPPROTO_ICMPV6:
741 spidx->ul_proto = nxt;
742 if (off + sizeof(struct icmp6_hdr) > m->m_pkthdr.len)
743 break;
744 m_copydata(m, off, sizeof(ih), (caddr_t)&ih);
745 ((struct sockaddr_in6 *)&spidx->src)->sin6_port =
746 htons((uint16_t)ih.icmp6_type);
747 ((struct sockaddr_in6 *)&spidx->dst)->sin6_port =
748 htons((uint16_t)ih.icmp6_code);
749 break;
750 default:
751 /* XXX Intermediate headers??? */
752 spidx->ul_proto = nxt;
753 break;
754 }
755 }
756
757 /* Assumes that m is sane. */
758 static int
ipsec6_setspidx_ipaddr(struct mbuf * m,struct secpolicyindex * spidx)759 ipsec6_setspidx_ipaddr(struct mbuf *m, struct secpolicyindex *spidx)
760 {
761 struct ip6_hdr *ip6 = NULL;
762 struct ip6_hdr ip6buf;
763 struct sockaddr_in6 *sin6;
764
765 if (m->m_len >= sizeof(*ip6))
766 ip6 = mtod(m, struct ip6_hdr *);
767 else {
768 m_copydata(m, 0, sizeof(ip6buf), (caddr_t)&ip6buf);
769 ip6 = &ip6buf;
770 }
771
772 sin6 = (struct sockaddr_in6 *)&spidx->src;
773 bzero(sin6, sizeof(*sin6));
774 sin6->sin6_family = AF_INET6;
775 sin6->sin6_len = sizeof(struct sockaddr_in6);
776 bcopy(&ip6->ip6_src, &sin6->sin6_addr, sizeof(ip6->ip6_src));
777 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_src)) {
778 sin6->sin6_addr.s6_addr16[1] = 0;
779 sin6->sin6_scope_id = ntohs(ip6->ip6_src.s6_addr16[1]);
780 }
781 spidx->prefs = sizeof(struct in6_addr) << 3;
782
783 sin6 = (struct sockaddr_in6 *)&spidx->dst;
784 bzero(sin6, sizeof(*sin6));
785 sin6->sin6_family = AF_INET6;
786 sin6->sin6_len = sizeof(struct sockaddr_in6);
787 bcopy(&ip6->ip6_dst, &sin6->sin6_addr, sizeof(ip6->ip6_dst));
788 if (IN6_IS_SCOPE_LINKLOCAL(&ip6->ip6_dst)) {
789 sin6->sin6_addr.s6_addr16[1] = 0;
790 sin6->sin6_scope_id = ntohs(ip6->ip6_dst.s6_addr16[1]);
791 }
792 spidx->prefd = sizeof(struct in6_addr) << 3;
793
794 return (0);
795 }
796 #endif
797
798 static void
ipsec_delpcbpolicy(struct inpcbpolicy * p)799 ipsec_delpcbpolicy(struct inpcbpolicy *p)
800 {
801
802 free(p, M_IPSEC_INPCB);
803 }
804
805 /* Initialize policy in PCB. */
806 int
ipsec_init_policy(struct socket * so,struct inpcbpolicy ** pcb_sp)807 ipsec_init_policy(struct socket *so, struct inpcbpolicy **pcb_sp)
808 {
809 struct inpcbpolicy *new;
810
811 /* Sanity check. */
812 if (so == NULL || pcb_sp == NULL)
813 panic("%s: NULL pointer was passed.\n", __func__);
814
815 new = (struct inpcbpolicy *) malloc(sizeof(struct inpcbpolicy),
816 M_IPSEC_INPCB, M_NOWAIT|M_ZERO);
817 if (new == NULL) {
818 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
819 return (ENOBUFS);
820 }
821
822 new->priv = IPSEC_IS_PRIVILEGED_SO(so);
823
824 if ((new->sp_in = KEY_NEWSP()) == NULL) {
825 ipsec_delpcbpolicy(new);
826 return (ENOBUFS);
827 }
828 new->sp_in->state = IPSEC_SPSTATE_ALIVE;
829 new->sp_in->policy = IPSEC_POLICY_ENTRUST;
830
831 if ((new->sp_out = KEY_NEWSP()) == NULL) {
832 KEY_FREESP(&new->sp_in);
833 ipsec_delpcbpolicy(new);
834 return (ENOBUFS);
835 }
836 new->sp_out->state = IPSEC_SPSTATE_ALIVE;
837 new->sp_out->policy = IPSEC_POLICY_ENTRUST;
838
839 *pcb_sp = new;
840
841 return (0);
842 }
843
844 /* Copy old IPsec policy into new. */
845 int
ipsec_copy_policy(struct inpcbpolicy * old,struct inpcbpolicy * new)846 ipsec_copy_policy(struct inpcbpolicy *old, struct inpcbpolicy *new)
847 {
848 struct secpolicy *sp;
849
850 sp = ipsec_deepcopy_policy(old->sp_in);
851 if (sp) {
852 KEY_FREESP(&new->sp_in);
853 new->sp_in = sp;
854 } else
855 return (ENOBUFS);
856
857 sp = ipsec_deepcopy_policy(old->sp_out);
858 if (sp) {
859 KEY_FREESP(&new->sp_out);
860 new->sp_out = sp;
861 } else
862 return (ENOBUFS);
863
864 new->priv = old->priv;
865
866 return (0);
867 }
868
869 struct ipsecrequest *
ipsec_newisr(void)870 ipsec_newisr(void)
871 {
872 struct ipsecrequest *p;
873
874 p = malloc(sizeof(struct ipsecrequest), M_IPSEC_SR, M_NOWAIT|M_ZERO);
875 if (p != NULL)
876 IPSECREQUEST_LOCK_INIT(p);
877 return (p);
878 }
879
880 void
ipsec_delisr(struct ipsecrequest * p)881 ipsec_delisr(struct ipsecrequest *p)
882 {
883
884 IPSECREQUEST_LOCK_DESTROY(p);
885 free(p, M_IPSEC_SR);
886 }
887
888 /* Deep-copy a policy in PCB. */
889 static struct secpolicy *
ipsec_deepcopy_policy(struct secpolicy * src)890 ipsec_deepcopy_policy(struct secpolicy *src)
891 {
892 struct ipsecrequest *newchain = NULL;
893 struct ipsecrequest *p;
894 struct ipsecrequest **q;
895 struct ipsecrequest *r;
896 struct secpolicy *dst;
897
898 if (src == NULL)
899 return (NULL);
900 dst = KEY_NEWSP();
901 if (dst == NULL)
902 return (NULL);
903
904 /*
905 * Deep-copy IPsec request chain. This is required since struct
906 * ipsecrequest is not reference counted.
907 */
908 q = &newchain;
909 for (p = src->req; p; p = p->next) {
910 *q = ipsec_newisr();
911 if (*q == NULL)
912 goto fail;
913 (*q)->saidx.proto = p->saidx.proto;
914 (*q)->saidx.mode = p->saidx.mode;
915 (*q)->level = p->level;
916 (*q)->saidx.reqid = p->saidx.reqid;
917
918 bcopy(&p->saidx.src, &(*q)->saidx.src, sizeof((*q)->saidx.src));
919 bcopy(&p->saidx.dst, &(*q)->saidx.dst, sizeof((*q)->saidx.dst));
920
921 (*q)->sp = dst;
922
923 q = &((*q)->next);
924 }
925
926 dst->req = newchain;
927 dst->state = src->state;
928 dst->policy = src->policy;
929 /* Do not touch the refcnt fields. */
930
931 return (dst);
932
933 fail:
934 for (p = newchain; p; p = r) {
935 r = p->next;
936 ipsec_delisr(p);
937 p = NULL;
938 }
939 KEY_FREESP(&dst);
940 return (NULL);
941 }
942
943 /* Set policy and IPsec request if present. */
944 static int
ipsec_set_policy_internal(struct secpolicy ** pcb_sp,int optname,caddr_t request,size_t len,struct ucred * cred)945 ipsec_set_policy_internal(struct secpolicy **pcb_sp, int optname,
946 caddr_t request, size_t len, struct ucred *cred)
947 {
948 struct sadb_x_policy *xpl;
949 struct secpolicy *newsp = NULL;
950 int error;
951
952 /* Sanity check. */
953 if (pcb_sp == NULL || *pcb_sp == NULL || request == NULL)
954 return (EINVAL);
955 if (len < sizeof(*xpl))
956 return (EINVAL);
957 xpl = (struct sadb_x_policy *)request;
958
959 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
960 printf("%s: passed policy\n", __func__);
961 kdebug_sadb_x_policy((struct sadb_ext *)xpl));
962
963 /* Check policy type. */
964 /* ipsec_set_policy_internal() accepts IPSEC, ENTRUST and BYPASS. */
965 if (xpl->sadb_x_policy_type == IPSEC_POLICY_DISCARD
966 || xpl->sadb_x_policy_type == IPSEC_POLICY_NONE)
967 return (EINVAL);
968
969 /* Check privileged socket. */
970 if (cred != NULL && xpl->sadb_x_policy_type == IPSEC_POLICY_BYPASS) {
971 error = priv_check_cred(cred, PRIV_NETINET_IPSEC, 0);
972 if (error)
973 return (EACCES);
974 }
975
976 /* Allocating new SP entry. */
977 if ((newsp = key_msg2sp(xpl, len, &error)) == NULL)
978 return (error);
979
980 newsp->state = IPSEC_SPSTATE_ALIVE;
981
982 /* Clear old SP and set new SP. */
983 KEY_FREESP(pcb_sp);
984 *pcb_sp = newsp;
985 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
986 printf("%s: new policy\n", __func__);
987 kdebug_secpolicy(newsp));
988
989 return (0);
990 }
991
992 int
ipsec_set_policy(struct inpcb * inp,int optname,caddr_t request,size_t len,struct ucred * cred)993 ipsec_set_policy(struct inpcb *inp, int optname, caddr_t request,
994 size_t len, struct ucred *cred)
995 {
996 struct sadb_x_policy *xpl;
997 struct secpolicy **pcb_sp;
998
999 /* Sanity check. */
1000 if (inp == NULL || request == NULL)
1001 return (EINVAL);
1002 if (len < sizeof(*xpl))
1003 return (EINVAL);
1004 xpl = (struct sadb_x_policy *)request;
1005
1006 /* Select direction. */
1007 switch (xpl->sadb_x_policy_dir) {
1008 case IPSEC_DIR_INBOUND:
1009 pcb_sp = &inp->inp_sp->sp_in;
1010 break;
1011 case IPSEC_DIR_OUTBOUND:
1012 pcb_sp = &inp->inp_sp->sp_out;
1013 break;
1014 default:
1015 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1016 xpl->sadb_x_policy_dir));
1017 return (EINVAL);
1018 }
1019
1020 return (ipsec_set_policy_internal(pcb_sp, optname, request, len, cred));
1021 }
1022
1023 int
ipsec_get_policy(struct inpcb * inp,caddr_t request,size_t len,struct mbuf ** mp)1024 ipsec_get_policy(struct inpcb *inp, caddr_t request, size_t len,
1025 struct mbuf **mp)
1026 {
1027 struct sadb_x_policy *xpl;
1028 struct secpolicy *pcb_sp;
1029
1030 /* Sanity check. */
1031 if (inp == NULL || request == NULL || mp == NULL)
1032 return (EINVAL);
1033 IPSEC_ASSERT(inp->inp_sp != NULL, ("null inp_sp"));
1034 if (len < sizeof(*xpl))
1035 return (EINVAL);
1036 xpl = (struct sadb_x_policy *)request;
1037
1038 /* Select direction. */
1039 switch (xpl->sadb_x_policy_dir) {
1040 case IPSEC_DIR_INBOUND:
1041 pcb_sp = inp->inp_sp->sp_in;
1042 break;
1043 case IPSEC_DIR_OUTBOUND:
1044 pcb_sp = inp->inp_sp->sp_out;
1045 break;
1046 default:
1047 ipseclog((LOG_ERR, "%s: invalid direction=%u\n", __func__,
1048 xpl->sadb_x_policy_dir));
1049 return (EINVAL);
1050 }
1051
1052 /* Sanity check. Should be an IPSEC_ASSERT. */
1053 if (pcb_sp == NULL)
1054 return (EINVAL);
1055
1056 *mp = key_sp2msg(pcb_sp);
1057 if (!*mp) {
1058 ipseclog((LOG_DEBUG, "%s: No more memory.\n", __func__));
1059 return (ENOBUFS);
1060 }
1061
1062 (*mp)->m_type = MT_DATA;
1063 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1064 printf("%s:\n", __func__); kdebug_mbuf(*mp));
1065
1066 return (0);
1067 }
1068
1069 /* Delete policy in PCB. */
1070 int
ipsec_delete_pcbpolicy(struct inpcb * inp)1071 ipsec_delete_pcbpolicy(struct inpcb *inp)
1072 {
1073 IPSEC_ASSERT(inp != NULL, ("null inp"));
1074
1075 if (inp->inp_sp == NULL)
1076 return (0);
1077
1078 if (inp->inp_sp->sp_in != NULL)
1079 KEY_FREESP(&inp->inp_sp->sp_in);
1080
1081 if (inp->inp_sp->sp_out != NULL)
1082 KEY_FREESP(&inp->inp_sp->sp_out);
1083
1084 ipsec_delpcbpolicy(inp->inp_sp);
1085 inp->inp_sp = NULL;
1086
1087 return (0);
1088 }
1089
1090 /*
1091 * Return current level.
1092 * Either IPSEC_LEVEL_USE or IPSEC_LEVEL_REQUIRE are always returned.
1093 */
1094 u_int
ipsec_get_reqlevel(struct ipsecrequest * isr)1095 ipsec_get_reqlevel(struct ipsecrequest *isr)
1096 {
1097 u_int level = 0;
1098 u_int esp_trans_deflev, esp_net_deflev;
1099 u_int ah_trans_deflev, ah_net_deflev;
1100
1101 IPSEC_ASSERT(isr != NULL && isr->sp != NULL, ("null argument"));
1102 IPSEC_ASSERT(isr->sp->spidx.src.sa.sa_family == isr->sp->spidx.dst.sa.sa_family,
1103 ("af family mismatch, src %u, dst %u",
1104 isr->sp->spidx.src.sa.sa_family,
1105 isr->sp->spidx.dst.sa.sa_family));
1106
1107 /* XXX Note that we have ipseclog() expanded here - code sync issue. */
1108 #define IPSEC_CHECK_DEFAULT(lev) \
1109 (((lev) != IPSEC_LEVEL_USE && (lev) != IPSEC_LEVEL_REQUIRE \
1110 && (lev) != IPSEC_LEVEL_UNIQUE) \
1111 ? (V_ipsec_debug \
1112 ? log(LOG_INFO, "fixed system default level " #lev ":%d->%d\n",\
1113 (lev), IPSEC_LEVEL_REQUIRE) \
1114 : 0), \
1115 (lev) = IPSEC_LEVEL_REQUIRE, \
1116 (lev) \
1117 : (lev))
1118
1119 /* Set default level. */
1120 switch (((struct sockaddr *)&isr->sp->spidx.src)->sa_family) {
1121 #ifdef INET
1122 case AF_INET:
1123 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_trans_deflev);
1124 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_esp_net_deflev);
1125 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_trans_deflev);
1126 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip4_ah_net_deflev);
1127 break;
1128 #endif
1129 #ifdef INET6
1130 case AF_INET6:
1131 esp_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_trans_deflev);
1132 esp_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_esp_net_deflev);
1133 ah_trans_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_trans_deflev);
1134 ah_net_deflev = IPSEC_CHECK_DEFAULT(V_ip6_ah_net_deflev);
1135 break;
1136 #endif /* INET6 */
1137 default:
1138 panic("%s: unknown af %u",
1139 __func__, isr->sp->spidx.src.sa.sa_family);
1140 }
1141
1142 #undef IPSEC_CHECK_DEFAULT
1143
1144 /* Set level. */
1145 switch (isr->level) {
1146 case IPSEC_LEVEL_DEFAULT:
1147 switch (isr->saidx.proto) {
1148 case IPPROTO_ESP:
1149 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1150 level = esp_net_deflev;
1151 else
1152 level = esp_trans_deflev;
1153 break;
1154 case IPPROTO_AH:
1155 if (isr->saidx.mode == IPSEC_MODE_TUNNEL)
1156 level = ah_net_deflev;
1157 else
1158 level = ah_trans_deflev;
1159 break;
1160 case IPPROTO_IPCOMP:
1161 /*
1162 * We don't really care, as IPcomp document says that
1163 * we shouldn't compress small packets.
1164 */
1165 level = IPSEC_LEVEL_USE;
1166 break;
1167 default:
1168 panic("%s: Illegal protocol defined %u\n", __func__,
1169 isr->saidx.proto);
1170 }
1171 break;
1172
1173 case IPSEC_LEVEL_USE:
1174 case IPSEC_LEVEL_REQUIRE:
1175 level = isr->level;
1176 break;
1177 case IPSEC_LEVEL_UNIQUE:
1178 level = IPSEC_LEVEL_REQUIRE;
1179 break;
1180
1181 default:
1182 panic("%s: Illegal IPsec level %u\n", __func__, isr->level);
1183 }
1184
1185 return (level);
1186 }
1187
1188 /*
1189 * Check security policy requirements against the actual
1190 * packet contents. Return one if the packet should be
1191 * reject as "invalid"; otherwiser return zero to have the
1192 * packet treated as "valid".
1193 *
1194 * OUT:
1195 * 0: valid
1196 * 1: invalid
1197 */
1198 int
ipsec_in_reject(struct secpolicy * sp,struct mbuf * m)1199 ipsec_in_reject(struct secpolicy *sp, struct mbuf *m)
1200 {
1201 struct ipsecrequest *isr;
1202 int need_auth;
1203
1204 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1205 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1206
1207 /* Check policy. */
1208 switch (sp->policy) {
1209 case IPSEC_POLICY_DISCARD:
1210 return (1);
1211 case IPSEC_POLICY_BYPASS:
1212 case IPSEC_POLICY_NONE:
1213 return (0);
1214 }
1215
1216 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1217 ("invalid policy %u", sp->policy));
1218
1219 /* XXX Should compare policy against IPsec header history. */
1220
1221 need_auth = 0;
1222 for (isr = sp->req; isr != NULL; isr = isr->next) {
1223 if (ipsec_get_reqlevel(isr) != IPSEC_LEVEL_REQUIRE)
1224 continue;
1225 switch (isr->saidx.proto) {
1226 case IPPROTO_ESP:
1227 if ((m->m_flags & M_DECRYPTED) == 0) {
1228 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1229 printf("%s: ESP m_flags:%x\n", __func__,
1230 m->m_flags));
1231 return (1);
1232 }
1233
1234 if (!need_auth &&
1235 isr->sav != NULL &&
1236 isr->sav->tdb_authalgxform != NULL &&
1237 (m->m_flags & M_AUTHIPDGM) == 0) {
1238 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1239 printf("%s: ESP/AH m_flags:%x\n", __func__,
1240 m->m_flags));
1241 return (1);
1242 }
1243 break;
1244 case IPPROTO_AH:
1245 need_auth = 1;
1246 if ((m->m_flags & M_AUTHIPHDR) == 0) {
1247 KEYDEBUG(KEYDEBUG_IPSEC_DUMP,
1248 printf("%s: AH m_flags:%x\n", __func__,
1249 m->m_flags));
1250 return (1);
1251 }
1252 break;
1253 case IPPROTO_IPCOMP:
1254 /*
1255 * We don't really care, as IPcomp document
1256 * says that we shouldn't compress small
1257 * packets. IPComp policy should always be
1258 * treated as being in "use" level.
1259 */
1260 break;
1261 }
1262 }
1263 return (0); /* Valid. */
1264 }
1265
1266 static int
ipsec46_in_reject(struct mbuf * m,struct inpcb * inp)1267 ipsec46_in_reject(struct mbuf *m, struct inpcb *inp)
1268 {
1269 struct secpolicy *sp;
1270 int error;
1271 int result;
1272
1273 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1274
1275 /*
1276 * Get SP for this packet.
1277 * When we are called from ip_forward(), we call
1278 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1279 */
1280 if (inp == NULL)
1281 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, IP_FORWARDING, &error);
1282 else
1283 sp = ipsec_getpolicybysock(m, IPSEC_DIR_INBOUND, inp, &error);
1284
1285 if (sp != NULL) {
1286 result = ipsec_in_reject(sp, m);
1287 KEY_FREESP(&sp);
1288 } else {
1289 result = 0; /* XXX Should be panic?
1290 * -> No, there may be error. */
1291 }
1292 return (result);
1293 }
1294
1295 /*
1296 * Check AH/ESP integrity.
1297 * This function is called from tcp_input(), udp_input(),
1298 * and {ah,esp}4_input for tunnel mode.
1299 */
1300 int
ipsec4_in_reject(struct mbuf * m,struct inpcb * inp)1301 ipsec4_in_reject(struct mbuf *m, struct inpcb *inp)
1302 {
1303 int result;
1304
1305 result = ipsec46_in_reject(m, inp);
1306 if (result)
1307 IPSECSTAT_INC(ips_in_polvio);
1308
1309 return (result);
1310 }
1311
1312 #ifdef INET6
1313 /*
1314 * Check AH/ESP integrity.
1315 * This function is called from tcp6_input(), udp6_input(),
1316 * and {ah,esp}6_input for tunnel mode.
1317 */
1318 int
ipsec6_in_reject(struct mbuf * m,struct inpcb * inp)1319 ipsec6_in_reject(struct mbuf *m, struct inpcb *inp)
1320 {
1321 int result;
1322
1323 result = ipsec46_in_reject(m, inp);
1324 if (result)
1325 IPSEC6STAT_INC(ips_in_polvio);
1326
1327 return (result);
1328 }
1329 #endif
1330
1331 /*
1332 * Compute the byte size to be occupied by IPsec header.
1333 * In case it is tunnelled, it includes the size of outer IP header.
1334 * NOTE: SP passed is freed in this function.
1335 */
1336 static size_t
ipsec_hdrsiz_internal(struct secpolicy * sp)1337 ipsec_hdrsiz_internal(struct secpolicy *sp)
1338 {
1339 struct ipsecrequest *isr;
1340 size_t size;
1341
1342 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1343 printf("%s: using SP\n", __func__); kdebug_secpolicy(sp));
1344
1345 switch (sp->policy) {
1346 case IPSEC_POLICY_DISCARD:
1347 case IPSEC_POLICY_BYPASS:
1348 case IPSEC_POLICY_NONE:
1349 return (0);
1350 }
1351
1352 IPSEC_ASSERT(sp->policy == IPSEC_POLICY_IPSEC,
1353 ("invalid policy %u", sp->policy));
1354
1355 size = 0;
1356 for (isr = sp->req; isr != NULL; isr = isr->next) {
1357 size_t clen = 0;
1358
1359 switch (isr->saidx.proto) {
1360 case IPPROTO_ESP:
1361 clen = esp_hdrsiz(isr->sav);
1362 break;
1363 case IPPROTO_AH:
1364 clen = ah_hdrsiz(isr->sav);
1365 break;
1366 case IPPROTO_IPCOMP:
1367 clen = sizeof(struct ipcomp);
1368 break;
1369 }
1370
1371 if (isr->saidx.mode == IPSEC_MODE_TUNNEL) {
1372 switch (isr->saidx.dst.sa.sa_family) {
1373 case AF_INET:
1374 clen += sizeof(struct ip);
1375 break;
1376 #ifdef INET6
1377 case AF_INET6:
1378 clen += sizeof(struct ip6_hdr);
1379 break;
1380 #endif
1381 default:
1382 ipseclog((LOG_ERR, "%s: unknown AF %d in "
1383 "IPsec tunnel SA\n", __func__,
1384 ((struct sockaddr *)&isr->saidx.dst)->sa_family));
1385 break;
1386 }
1387 }
1388 size += clen;
1389 }
1390
1391 return (size);
1392 }
1393
1394 /*
1395 * This function is called from ipsec_hdrsiz_tcp(), ip_ipsec_mtu(),
1396 * disabled ip6_ipsec_mtu() and ip6_forward().
1397 */
1398 size_t
ipsec_hdrsiz(struct mbuf * m,u_int dir,struct inpcb * inp)1399 ipsec_hdrsiz(struct mbuf *m, u_int dir, struct inpcb *inp)
1400 {
1401 struct secpolicy *sp;
1402 int error;
1403 size_t size;
1404
1405 IPSEC_ASSERT(m != NULL, ("null mbuf"));
1406
1407 /* Get SP for this packet.
1408 * When we are called from ip_forward(), we call
1409 * ipsec_getpolicybyaddr() with IP_FORWARDING flag.
1410 */
1411 if (inp == NULL)
1412 sp = ipsec_getpolicybyaddr(m, dir, IP_FORWARDING, &error);
1413 else
1414 sp = ipsec_getpolicybysock(m, dir, inp, &error);
1415
1416 if (sp != NULL) {
1417 size = ipsec_hdrsiz_internal(sp);
1418 KEYDEBUG(KEYDEBUG_IPSEC_DATA,
1419 printf("%s: size:%lu.\n", __func__,
1420 (unsigned long)size));
1421
1422 KEY_FREESP(&sp);
1423 } else {
1424 size = 0; /* XXX Should be panic?
1425 * -> No, we are called w/o knowing if
1426 * IPsec processing is needed. */
1427 }
1428 return (size);
1429 }
1430
1431 /*
1432 * Check the variable replay window.
1433 * ipsec_chkreplay() performs replay check before ICV verification.
1434 * ipsec_updatereplay() updates replay bitmap. This must be called after
1435 * ICV verification (it also performs replay check, which is usually done
1436 * beforehand).
1437 * 0 (zero) is returned if packet disallowed, 1 if packet permitted.
1438 *
1439 * Based on RFC 2401.
1440 */
1441 int
ipsec_chkreplay(u_int32_t seq,struct secasvar * sav)1442 ipsec_chkreplay(u_int32_t seq, struct secasvar *sav)
1443 {
1444 const struct secreplay *replay;
1445 u_int32_t diff;
1446 int fr;
1447 u_int32_t wsizeb; /* Constant: bits of window size. */
1448 int frlast; /* Constant: last frame. */
1449
1450 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1451 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1452
1453 replay = sav->replay;
1454
1455 if (replay->wsize == 0)
1456 return (1); /* No need to check replay. */
1457
1458 /* Constant. */
1459 frlast = replay->wsize - 1;
1460 wsizeb = replay->wsize << 3;
1461
1462 /* Sequence number of 0 is invalid. */
1463 if (seq == 0)
1464 return (0);
1465
1466 /* First time is always okay. */
1467 if (replay->count == 0)
1468 return (1);
1469
1470 if (seq > replay->lastseq) {
1471 /* Larger sequences are okay. */
1472 return (1);
1473 } else {
1474 /* seq is equal or less than lastseq. */
1475 diff = replay->lastseq - seq;
1476
1477 /* Over range to check, i.e. too old or wrapped. */
1478 if (diff >= wsizeb)
1479 return (0);
1480
1481 fr = frlast - diff / 8;
1482
1483 /* This packet already seen? */
1484 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1485 return (0);
1486
1487 /* Out of order but good. */
1488 return (1);
1489 }
1490 }
1491
1492 /*
1493 * Check replay counter whether to update or not.
1494 * OUT: 0: OK
1495 * 1: NG
1496 */
1497 int
ipsec_updatereplay(u_int32_t seq,struct secasvar * sav)1498 ipsec_updatereplay(u_int32_t seq, struct secasvar *sav)
1499 {
1500 struct secreplay *replay;
1501 u_int32_t diff;
1502 int fr;
1503 u_int32_t wsizeb; /* Constant: bits of window size. */
1504 int frlast; /* Constant: last frame. */
1505
1506 IPSEC_ASSERT(sav != NULL, ("Null SA"));
1507 IPSEC_ASSERT(sav->replay != NULL, ("Null replay state"));
1508
1509 replay = sav->replay;
1510
1511 if (replay->wsize == 0)
1512 goto ok; /* No need to check replay. */
1513
1514 /* Constant. */
1515 frlast = replay->wsize - 1;
1516 wsizeb = replay->wsize << 3;
1517
1518 /* Sequence number of 0 is invalid. */
1519 if (seq == 0)
1520 return (1);
1521
1522 /* First time. */
1523 if (replay->count == 0) {
1524 replay->lastseq = seq;
1525 bzero(replay->bitmap, replay->wsize);
1526 (replay->bitmap)[frlast] = 1;
1527 goto ok;
1528 }
1529
1530 if (seq > replay->lastseq) {
1531 /* seq is larger than lastseq. */
1532 diff = seq - replay->lastseq;
1533
1534 /* New larger sequence number. */
1535 if (diff < wsizeb) {
1536 /* In window. */
1537 /* Set bit for this packet. */
1538 vshiftl(replay->bitmap, diff, replay->wsize);
1539 (replay->bitmap)[frlast] |= 1;
1540 } else {
1541 /* This packet has a "way larger". */
1542 bzero(replay->bitmap, replay->wsize);
1543 (replay->bitmap)[frlast] = 1;
1544 }
1545 replay->lastseq = seq;
1546
1547 /* Larger is good. */
1548 } else {
1549 /* seq is equal or less than lastseq. */
1550 diff = replay->lastseq - seq;
1551
1552 /* Over range to check, i.e. too old or wrapped. */
1553 if (diff >= wsizeb)
1554 return (1);
1555
1556 fr = frlast - diff / 8;
1557
1558 /* This packet already seen? */
1559 if ((replay->bitmap)[fr] & (1 << (diff % 8)))
1560 return (1);
1561
1562 /* Mark as seen. */
1563 (replay->bitmap)[fr] |= (1 << (diff % 8));
1564
1565 /* Out of order but good. */
1566 }
1567
1568 ok:
1569 if (replay->count == ~0) {
1570
1571 /* Set overflow flag. */
1572 replay->overflow++;
1573
1574 /* Don't increment, no more packets accepted. */
1575 if ((sav->flags & SADB_X_EXT_CYCSEQ) == 0)
1576 return (1);
1577
1578 ipseclog((LOG_WARNING, "%s: replay counter made %d cycle. %s\n",
1579 __func__, replay->overflow, ipsec_logsastr(sav)));
1580 }
1581
1582 replay->count++;
1583
1584 return (0);
1585 }
1586
1587 /*
1588 * Shift variable length buffer to left.
1589 * IN: bitmap: pointer to the buffer
1590 * nbit: the number of to shift.
1591 * wsize: buffer size (bytes).
1592 */
1593 static void
vshiftl(unsigned char * bitmap,int nbit,int wsize)1594 vshiftl(unsigned char *bitmap, int nbit, int wsize)
1595 {
1596 int s, j, i;
1597 unsigned char over;
1598
1599 for (j = 0; j < nbit; j += 8) {
1600 s = (nbit - j < 8) ? (nbit - j): 8;
1601 bitmap[0] <<= s;
1602 for (i = 1; i < wsize; i++) {
1603 over = (bitmap[i] >> (8 - s));
1604 bitmap[i] <<= s;
1605 bitmap[i-1] |= over;
1606 }
1607 }
1608 }
1609
1610 #ifdef INET
1611 /* Return a printable string for the IPv4 address. */
1612 static char *
inet_ntoa4(struct in_addr ina)1613 inet_ntoa4(struct in_addr ina)
1614 {
1615 static char buf[4][4 * sizeof "123" + 4];
1616 unsigned char *ucp = (unsigned char *) &ina;
1617 static int i = 3;
1618
1619 /* XXX-BZ Returns static buffer. */
1620 i = (i + 1) % 4;
1621 sprintf(buf[i], "%d.%d.%d.%d", ucp[0] & 0xff, ucp[1] & 0xff,
1622 ucp[2] & 0xff, ucp[3] & 0xff);
1623 return (buf[i]);
1624 }
1625 #endif
1626
1627 /* Return a printable string for the address. */
1628 char *
ipsec_address(union sockaddr_union * sa)1629 ipsec_address(union sockaddr_union* sa)
1630 {
1631 #ifdef INET6
1632 char ip6buf[INET6_ADDRSTRLEN];
1633 #endif
1634
1635 switch (sa->sa.sa_family) {
1636 #ifdef INET
1637 case AF_INET:
1638 return (inet_ntoa4(sa->sin.sin_addr));
1639 #endif /* INET */
1640 #ifdef INET6
1641 case AF_INET6:
1642 return (ip6_sprintf(ip6buf, &sa->sin6.sin6_addr));
1643 #endif /* INET6 */
1644 default:
1645 return ("(unknown address family)");
1646 }
1647 }
1648
1649 const char *
ipsec_logsastr(struct secasvar * sav)1650 ipsec_logsastr(struct secasvar *sav)
1651 {
1652 static char buf[256];
1653 char *p;
1654 struct secasindex *saidx = &sav->sah->saidx;
1655
1656 IPSEC_ASSERT(saidx->src.sa.sa_family == saidx->dst.sa.sa_family,
1657 ("address family mismatch"));
1658
1659 p = buf;
1660 snprintf(buf, sizeof(buf), "SA(SPI=%u ", (u_int32_t)ntohl(sav->spi));
1661 while (p && *p)
1662 p++;
1663 /* NB: only use ipsec_address on one address at a time. */
1664 snprintf(p, sizeof (buf) - (p - buf), "src=%s ",
1665 ipsec_address(&saidx->src));
1666 while (p && *p)
1667 p++;
1668 snprintf(p, sizeof (buf) - (p - buf), "dst=%s)",
1669 ipsec_address(&saidx->dst));
1670
1671 return (buf);
1672 }
1673
1674 void
ipsec_dumpmbuf(struct mbuf * m)1675 ipsec_dumpmbuf(struct mbuf *m)
1676 {
1677 int totlen;
1678 int i;
1679 u_char *p;
1680
1681 totlen = 0;
1682 printf("---\n");
1683 while (m) {
1684 p = mtod(m, u_char *);
1685 for (i = 0; i < m->m_len; i++) {
1686 printf("%02x ", p[i]);
1687 totlen++;
1688 if (totlen % 16 == 0)
1689 printf("\n");
1690 }
1691 m = m->m_next;
1692 }
1693 if (totlen % 16 != 0)
1694 printf("\n");
1695 printf("---\n");
1696 }
1697
1698 static void
ipsec_init(const void * unused __unused)1699 ipsec_init(const void *unused __unused)
1700 {
1701
1702 SECPOLICY_LOCK_INIT(&V_ip4_def_policy);
1703 V_ip4_def_policy.refcnt = 1; /* NB: disallow free. */
1704 }
1705 VNET_SYSINIT(ipsec_init, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, ipsec_init,
1706 NULL);
1707
1708
1709 /* XXX This stuff doesn't belong here... */
1710
1711 static struct xformsw* xforms = NULL;
1712
1713 /*
1714 * Register a transform; typically at system startup.
1715 */
1716 void
xform_register(struct xformsw * xsp)1717 xform_register(struct xformsw* xsp)
1718 {
1719
1720 xsp->xf_next = xforms;
1721 xforms = xsp;
1722 }
1723
1724 /*
1725 * Initialize transform support in an sav.
1726 */
1727 int
xform_init(struct secasvar * sav,int xftype)1728 xform_init(struct secasvar *sav, int xftype)
1729 {
1730 struct xformsw *xsp;
1731
1732 if (sav->tdb_xform != NULL) /* Previously initialized. */
1733 return (0);
1734 for (xsp = xforms; xsp; xsp = xsp->xf_next)
1735 if (xsp->xf_type == xftype)
1736 return ((*xsp->xf_init)(sav, xsp));
1737 return (EINVAL);
1738 }
1739