1/*	$NetBSD: policy.c,v 1.11 2009/07/03 06:41:46 tteras Exp $	*/
2
3/*	$KAME: policy.c,v 1.46 2001/11/16 04:08:10 sakane Exp $	*/
4
5/*
6 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include "config.h"
35
36#include <sys/param.h>
37#include <sys/types.h>
38#include <sys/socket.h>
39#include <sys/queue.h>
40
41#include <netinet/in.h>
42#include PATH_IPSEC_H
43
44#include <stdlib.h>
45#include <stdio.h>
46#include <string.h>
47#include <errno.h>
48
49#include "var.h"
50#include "misc.h"
51#include "vmbuf.h"
52#include "plog.h"
53#include "sockmisc.h"
54#include "debug.h"
55
56#include "policy.h"
57#include "localconf.h"
58#include "isakmp_var.h"
59#include "isakmp.h"
60#include "oakley.h"
61#include "handler.h"
62#include "strnames.h"
63#include "gcmalloc.h"
64
65static TAILQ_HEAD(_sptree, secpolicy) sptree;
66
67/* perform exact match against security policy table. */
68struct secpolicy *
69getsp(spidx)
70	struct policyindex *spidx;
71{
72	struct secpolicy *p;
73
74	for (p = TAILQ_FIRST(&sptree); p; p = TAILQ_NEXT(p, chain)) {
75		if (!cmpspidxstrict(spidx, &p->spidx))
76			return p;
77	}
78
79	return NULL;
80}
81
82/*
83 * perform non-exact match against security policy table, only if this is
84 * transport mode SA negotiation.  for example, 0.0.0.0/0 -> 0.0.0.0/0
85 * entry in policy.txt can be returned when we're negotiating transport
86 * mode SA.  this is how the kernel works.
87 */
88#if 1
89struct secpolicy *
90getsp_r(spidx)
91	struct policyindex *spidx;
92{
93	struct secpolicy *p;
94	struct secpolicy *found = NULL;
95
96	for (p = TAILQ_FIRST(&sptree); p; p = TAILQ_NEXT(p, chain)) {
97		if (!cmpspidxstrict(spidx, &p->spidx))
98			return p;
99
100		if (!found && !cmpspidxwild(spidx, &p->spidx))
101			found = p;
102	}
103
104	return found;
105}
106#else
107struct secpolicy *
108getsp_r(spidx, iph2)
109	struct policyindex *spidx;
110	struct ph2handle *iph2;
111{
112	struct secpolicy *p;
113	u_int8_t prefixlen;
114
115	plog(LLV_DEBUG, LOCATION, NULL, "checking for transport mode\n");
116
117	if (spidx->src.ss_family != spidx->dst.ss_family) {
118		plog(LLV_ERROR, LOCATION, NULL,
119			"address family mismatch, src:%d dst:%d\n",
120				spidx->src.ss_family,
121				spidx->dst.ss_family);
122		return NULL;
123	}
124	switch (spidx->src.ss_family) {
125	case AF_INET:
126		prefixlen = sizeof(struct in_addr) << 3;
127		break;
128#ifdef INET6
129	case AF_INET6:
130		prefixlen = sizeof(struct in6_addr) << 3;
131		break;
132#endif
133	default:
134		plog(LLV_ERROR, LOCATION, NULL,
135			"invalid family: %d\n", spidx->src.ss_family);
136		return NULL;
137	}
138
139	/* is it transport mode SA negotiation? */
140	plog(LLV_DEBUG, LOCATION, NULL, "src1: %s\n",
141		saddr2str(iph2->src));
142	plog(LLV_DEBUG, LOCATION, NULL, "src2: %s\n",
143		saddr2str((struct sockaddr *)&spidx->src));
144
145	if (cmpsaddr(iph2->src, (struct sockaddr *) &spidx->src) != CMPSADDR_MATCH ||
146	    spidx->prefs != prefixlen)
147		return NULL;
148
149	plog(LLV_DEBUG, LOCATION, NULL, "dst1: %s\n",
150		saddr2str(iph2->dst));
151	plog(LLV_DEBUG, LOCATION, NULL, "dst2: %s\n",
152		saddr2str((struct sockaddr *)&spidx->dst));
153
154	if (cmpsaddr(iph2->dst, (struct sockaddr *) &spidx->dst) != CMPSADDR_MATCH ||
155	    spidx->prefd != prefixlen)
156		return NULL;
157
158	plog(LLV_DEBUG, LOCATION, NULL, "looks to be transport mode\n");
159
160	for (p = TAILQ_FIRST(&sptree); p; p = TAILQ_NEXT(p, chain)) {
161		if (!cmpspidx_wild(spidx, &p->spidx))
162			return p;
163	}
164
165	return NULL;
166}
167#endif
168
169struct secpolicy *
170getspbyspid(spid)
171	u_int32_t spid;
172{
173	struct secpolicy *p;
174
175	for (p = TAILQ_FIRST(&sptree); p; p = TAILQ_NEXT(p, chain)) {
176		if (p->id == spid)
177			return p;
178	}
179
180	return NULL;
181}
182
183/*
184 * compare policyindex.
185 * a: subject b: db
186 * OUT:	0:	equal
187 *	1:	not equal
188 */
189int
190cmpspidxstrict(a, b)
191	struct policyindex *a, *b;
192{
193	plog(LLV_DEBUG, LOCATION, NULL, "sub:%p: %s\n", a, spidx2str(a));
194	plog(LLV_DEBUG, LOCATION, NULL, "db :%p: %s\n", b, spidx2str(b));
195
196	/* XXX don't check direction now, but it's to be checked carefully. */
197	if (a->dir != b->dir
198	 || a->prefs != b->prefs
199	 || a->prefd != b->prefd
200	 || a->ul_proto != b->ul_proto)
201		return 1;
202
203	if (cmpsaddr((struct sockaddr *) &a->src,
204		     (struct sockaddr *) &b->src) != CMPSADDR_MATCH)
205		return 1;
206	if (cmpsaddr((struct sockaddr *) &a->dst,
207		     (struct sockaddr *) &b->dst) != CMPSADDR_MATCH)
208		return 1;
209
210#ifdef HAVE_SECCTX
211	if (a->sec_ctx.ctx_alg != b->sec_ctx.ctx_alg
212	    || a->sec_ctx.ctx_doi != b->sec_ctx.ctx_doi
213	    || !within_range(a->sec_ctx.ctx_str, b->sec_ctx.ctx_str))
214		return 1;
215#endif
216	return 0;
217}
218
219/*
220 * compare policyindex, with wildcard address/protocol match.
221 * a: subject b: db, can contain wildcard things.
222 * OUT:	0:	equal
223 *	1:	not equal
224 */
225int
226cmpspidxwild(a, b)
227	struct policyindex *a, *b;
228{
229	struct sockaddr_storage sa1, sa2;
230
231	plog(LLV_DEBUG, LOCATION, NULL, "sub:%p: %s\n", a, spidx2str(a));
232	plog(LLV_DEBUG, LOCATION, NULL, "db: %p: %s\n", b, spidx2str(b));
233
234	if (!(b->dir == IPSEC_DIR_ANY || a->dir == b->dir))
235		return 1;
236
237	if (!(b->ul_proto == IPSEC_ULPROTO_ANY ||
238	      a->ul_proto == b->ul_proto))
239		return 1;
240
241	if (a->src.ss_family != b->src.ss_family)
242		return 1;
243	if (a->dst.ss_family != b->dst.ss_family)
244		return 1;
245
246#ifndef __linux__
247	/* compare src address */
248	if (sizeof(sa1) < a->src.ss_len || sizeof(sa2) < b->src.ss_len) {
249		plog(LLV_ERROR, LOCATION, NULL,
250			"unexpected error: "
251			"src.ss_len:%d dst.ss_len:%d\n",
252			a->src.ss_len, b->src.ss_len);
253		return 1;
254	}
255#endif
256	mask_sockaddr((struct sockaddr *)&sa1, (struct sockaddr *)&a->src,
257		b->prefs);
258	mask_sockaddr((struct sockaddr *)&sa2, (struct sockaddr *)&b->src,
259		b->prefs);
260	plog(LLV_DEBUG, LOCATION, NULL, "%p masked with /%d: %s\n",
261		a, b->prefs, saddr2str((struct sockaddr *)&sa1));
262	plog(LLV_DEBUG, LOCATION, NULL, "%p masked with /%d: %s\n",
263		b, b->prefs, saddr2str((struct sockaddr *)&sa2));
264	if (cmpsaddr((struct sockaddr *)&sa1, (struct sockaddr *)&sa2) > CMPSADDR_WILDPORT_MATCH)
265		return 1;
266
267#ifndef __linux__
268	/* compare dst address */
269	if (sizeof(sa1) < a->dst.ss_len || sizeof(sa2) < b->dst.ss_len) {
270		plog(LLV_ERROR, LOCATION, NULL, "unexpected error\n");
271		exit(1);
272	}
273#endif
274	mask_sockaddr((struct sockaddr *)&sa1, (struct sockaddr *)&a->dst,
275		b->prefd);
276	mask_sockaddr((struct sockaddr *)&sa2, (struct sockaddr *)&b->dst,
277		b->prefd);
278	plog(LLV_DEBUG, LOCATION, NULL, "%p masked with /%d: %s\n",
279		a, b->prefd, saddr2str((struct sockaddr *)&sa1));
280	plog(LLV_DEBUG, LOCATION, NULL, "%p masked with /%d: %s\n",
281		b, b->prefd, saddr2str((struct sockaddr *)&sa2));
282	if (cmpsaddr((struct sockaddr *)&sa1, (struct sockaddr *)&sa2) > CMPSADDR_WILDPORT_MATCH)
283		return 1;
284
285#ifdef HAVE_SECCTX
286	if (a->sec_ctx.ctx_alg != b->sec_ctx.ctx_alg
287	    || a->sec_ctx.ctx_doi != b->sec_ctx.ctx_doi
288	    || !within_range(a->sec_ctx.ctx_str, b->sec_ctx.ctx_str))
289		return 1;
290#endif
291	return 0;
292}
293
294struct secpolicy *
295newsp()
296{
297	struct secpolicy *new;
298
299	new = racoon_calloc(1, sizeof(*new));
300	if (new == NULL)
301		return NULL;
302
303	return new;
304}
305
306void
307delsp(sp)
308	struct secpolicy *sp;
309{
310	struct ipsecrequest *req = NULL, *next;
311
312	for (req = sp->req; req; req = next) {
313		next = req->next;
314		racoon_free(req);
315	}
316
317	if (sp->local)
318		racoon_free(sp->local);
319	if (sp->remote)
320		racoon_free(sp->remote);
321
322	racoon_free(sp);
323}
324
325void
326delsp_bothdir(spidx0)
327	struct policyindex *spidx0;
328{
329	struct policyindex spidx;
330	struct secpolicy *sp;
331	struct sockaddr_storage src, dst;
332	u_int8_t prefs, prefd;
333
334	memcpy(&spidx, spidx0, sizeof(spidx));
335	switch (spidx.dir) {
336	case IPSEC_DIR_INBOUND:
337#ifdef HAVE_POLICY_FWD
338	case IPSEC_DIR_FWD:
339#endif
340		src   = spidx.src;
341		dst   = spidx.dst;
342		prefs = spidx.prefs;
343		prefd = spidx.prefd;
344		break;
345	case IPSEC_DIR_OUTBOUND:
346		src   = spidx.dst;
347		dst   = spidx.src;
348		prefs = spidx.prefd;
349		prefd = spidx.prefs;
350		break;
351	default:
352		return;
353	}
354
355	spidx.src   = src;
356	spidx.dst   = dst;
357	spidx.prefs = prefs;
358	spidx.prefd = prefd;
359	spidx.dir   = IPSEC_DIR_INBOUND;
360
361	sp = getsp(&spidx);
362	if (sp) {
363		remsp(sp);
364		delsp(sp);
365	}
366
367#ifdef HAVE_POLICY_FWD
368	spidx.dir   = IPSEC_DIR_FWD;
369
370	sp = getsp(&spidx);
371	if (sp) {
372		remsp(sp);
373		delsp(sp);
374	}
375#endif
376
377	spidx.src   = dst;
378	spidx.dst   = src;
379	spidx.prefs = prefd;
380	spidx.prefd = prefs;
381	spidx.dir   = IPSEC_DIR_OUTBOUND;
382
383	sp = getsp(&spidx);
384	if (sp) {
385		remsp(sp);
386		delsp(sp);
387	}
388}
389
390void
391inssp(new)
392	struct secpolicy *new;
393{
394#ifdef HAVE_PFKEY_POLICY_PRIORITY
395	struct secpolicy *p;
396
397	TAILQ_FOREACH(p, &sptree, chain) {
398		if (new->spidx.priority < p->spidx.priority) {
399			TAILQ_INSERT_BEFORE(p, new, chain);
400			return;
401		}
402	}
403	if (p == NULL)
404#endif
405		TAILQ_INSERT_TAIL(&sptree, new, chain);
406
407	return;
408}
409
410void
411remsp(sp)
412	struct secpolicy *sp;
413{
414	TAILQ_REMOVE(&sptree, sp, chain);
415}
416
417void
418flushsp()
419{
420	struct secpolicy *p, *next;
421
422	for (p = TAILQ_FIRST(&sptree); p; p = next) {
423		next = TAILQ_NEXT(p, chain);
424		remsp(p);
425		delsp(p);
426	}
427}
428
429void
430initsp()
431{
432	TAILQ_INIT(&sptree);
433}
434
435struct ipsecrequest *
436newipsecreq()
437{
438	struct ipsecrequest *new;
439
440	new = racoon_calloc(1, sizeof(*new));
441	if (new == NULL)
442		return NULL;
443
444	return new;
445}
446
447const char *
448spidx2str(spidx)
449	const struct policyindex *spidx;
450{
451	/* addr/pref[port] addr/pref[port] ul dir act */
452	static char buf[256];
453	char *p, *a, *b;
454	int blen, i;
455
456	blen = sizeof(buf) - 1;
457	p = buf;
458
459	a = saddr2str((const struct sockaddr *)&spidx->src);
460	for (b = a; *b != '\0'; b++)
461		if (*b == '[') {
462			*b = '\0';
463			b++;
464			break;
465		}
466	i = snprintf(p, blen, "%s/%d[%s ", a, spidx->prefs, b);
467	if (i < 0 || i >= blen)
468		return NULL;
469	p += i;
470	blen -= i;
471
472	a = saddr2str((const struct sockaddr *)&spidx->dst);
473	for (b = a; *b != '\0'; b++)
474		if (*b == '[') {
475			*b = '\0';
476			b++;
477			break;
478		}
479	i = snprintf(p, blen, "%s/%d[%s ", a, spidx->prefd, b);
480	if (i < 0 || i >= blen)
481		return NULL;
482	p += i;
483	blen -= i;
484
485	i = snprintf(p, blen, "proto=%s dir=%s",
486		s_proto(spidx->ul_proto), s_direction(spidx->dir));
487
488#ifdef HAVE_SECCTX
489	if (spidx->sec_ctx.ctx_strlen) {
490		p += i;
491		blen -= i;
492		snprintf(p, blen, " sec_ctx:doi=%d,alg=%d,len=%d,str=%s",
493			 spidx->sec_ctx.ctx_doi, spidx->sec_ctx.ctx_alg,
494			 spidx->sec_ctx.ctx_strlen, spidx->sec_ctx.ctx_str);
495	}
496#endif
497	return buf;
498}
499