1 /* $NetBSD: pf_ruleset.c,v 1.2 2008/06/18 09:06:27 yamt Exp $ */
2 /* $OpenBSD: pf_ruleset.c,v 1.1 2006/10/27 13:56:51 mcbride Exp $ */
3
4 /*
5 * Copyright (c) 2001 Daniel Hartmeier
6 * Copyright (c) 2002,2003 Henning Brauer
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 *
13 * - Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * - Redistributions in binary form must reproduce the above
16 * copyright notice, this list of conditions and the following
17 * disclaimer in the documentation and/or other materials provided
18 * with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
28 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
30 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31 * POSSIBILITY OF SUCH DAMAGE.
32 *
33 * Effort sponsored in part by the Defense Advanced Research Projects
34 * Agency (DARPA) and Air Force Research Laboratory, Air Force
35 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
36 *
37 */
38
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: pf_ruleset.c,v 1.2 2008/06/18 09:06:27 yamt Exp $");
41
42 #include <sys/param.h>
43 #include <sys/socket.h>
44 #ifdef _KERNEL
45 # include <sys/systm.h>
46 #endif /* _KERNEL */
47 #include <sys/mbuf.h>
48
49 #include <netinet/in.h>
50 #include <netinet/in_systm.h>
51 #include <netinet/ip.h>
52 #include <netinet/tcp.h>
53
54 #include <net/if.h>
55 #include <net/pfvar.h>
56
57 #ifdef INET6
58 #include <netinet/ip6.h>
59 #endif /* INET6 */
60
61
62 #ifdef _KERNEL
63 # define DPFPRINTF(format, x...) \
64 if (pf_status.debug >= PF_DEBUG_NOISY) \
65 printf(format , ##x)
66 #define rs_malloc(x) malloc(x, M_TEMP, M_WAITOK)
67 #define rs_free(x) free(x, M_TEMP)
68
69 #else
70 /* Userland equivalents so we can lend code to pfctl et al. */
71
72 # include <arpa/inet.h>
73 # include <errno.h>
74 # include <stdio.h>
75 # include <stdlib.h>
76 # include <string.h>
77 # define rs_malloc(x) malloc(x)
78 # define rs_free(x) free(x)
79
80 # ifdef PFDEBUG
81 # include <sys/stdarg.h>
82 # define DPFPRINTF(format, x...) fprintf(stderr, format , ##x)
83 # else
84 # define DPFPRINTF(format, x...) ((void)0)
85 # endif /* PFDEBUG */
86 #endif /* _KERNEL */
87
88
89 struct pf_anchor_global pf_anchors;
90 struct pf_anchor pf_main_anchor;
91
92 int pf_get_ruleset_number(u_int8_t);
93 void pf_init_ruleset(struct pf_ruleset *);
94 int pf_anchor_setup(struct pf_rule *,
95 const struct pf_ruleset *, const char *);
96 int pf_anchor_copyout(const struct pf_ruleset *,
97 const struct pf_rule *, struct pfioc_rule *);
98 void pf_anchor_remove(struct pf_rule *);
99
100 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
101
102 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
103 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
104
105 static __inline int
pf_anchor_compare(struct pf_anchor * a,struct pf_anchor * b)106 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
107 {
108 int c = strcmp(a->path, b->path);
109
110 return (c ? (c < 0 ? -1 : 1) : 0);
111 }
112
113 int
pf_get_ruleset_number(u_int8_t action)114 pf_get_ruleset_number(u_int8_t action)
115 {
116 switch (action) {
117 case PF_SCRUB:
118 case PF_NOSCRUB:
119 return (PF_RULESET_SCRUB);
120 break;
121 case PF_PASS:
122 case PF_DROP:
123 return (PF_RULESET_FILTER);
124 break;
125 case PF_NAT:
126 case PF_NONAT:
127 return (PF_RULESET_NAT);
128 break;
129 case PF_BINAT:
130 case PF_NOBINAT:
131 return (PF_RULESET_BINAT);
132 break;
133 case PF_RDR:
134 case PF_NORDR:
135 return (PF_RULESET_RDR);
136 break;
137 default:
138 return (PF_RULESET_MAX);
139 break;
140 }
141 }
142
143 void
pf_init_ruleset(struct pf_ruleset * ruleset)144 pf_init_ruleset(struct pf_ruleset *ruleset)
145 {
146 int i;
147
148 memset(ruleset, 0, sizeof(struct pf_ruleset));
149 for (i = 0; i < PF_RULESET_MAX; i++) {
150 TAILQ_INIT(&ruleset->rules[i].queues[0]);
151 TAILQ_INIT(&ruleset->rules[i].queues[1]);
152 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
153 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
154 }
155 }
156
157 struct pf_anchor *
pf_find_anchor(const char * path)158 pf_find_anchor(const char *path)
159 {
160 struct pf_anchor *key, *found;
161
162 key = (struct pf_anchor *)rs_malloc(sizeof(*key));
163 memset(key, 0, sizeof(*key));
164 strlcpy(key->path, path, sizeof(key->path));
165 found = RB_FIND(pf_anchor_global, &pf_anchors, key);
166 rs_free(key);
167 return (found);
168 }
169
170 struct pf_ruleset *
pf_find_ruleset(const char * path)171 pf_find_ruleset(const char *path)
172 {
173 struct pf_anchor *anchor;
174
175 while (*path == '/')
176 path++;
177 if (!*path)
178 return (&pf_main_ruleset);
179 anchor = pf_find_anchor(path);
180 if (anchor == NULL)
181 return (NULL);
182 else
183 return (&anchor->ruleset);
184 }
185
186 struct pf_ruleset *
pf_find_or_create_ruleset(const char * path)187 pf_find_or_create_ruleset(const char *path)
188 {
189 char *p, *q, *r;
190 struct pf_ruleset *ruleset;
191 struct pf_anchor *anchor = NULL /* XXX gcc */;
192 struct pf_anchor *dup, *parent = NULL;
193
194 if (path[0] == 0)
195 return (&pf_main_ruleset);
196 while (*path == '/')
197 path++;
198 ruleset = pf_find_ruleset(path);
199 if (ruleset != NULL)
200 return (ruleset);
201 p = (char *)rs_malloc(MAXPATHLEN);
202 bzero(p, MAXPATHLEN);
203 strlcpy(p, path, MAXPATHLEN);
204 while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
205 *q = 0;
206 if ((ruleset = pf_find_ruleset(p)) != NULL) {
207 parent = ruleset->anchor;
208 break;
209 }
210 }
211 if (q == NULL)
212 q = p;
213 else
214 q++;
215 strlcpy(p, path, MAXPATHLEN);
216 if (!*q) {
217 rs_free(p);
218 return (NULL);
219 }
220 while ((r = strchr(q, '/')) != NULL || *q) {
221 if (r != NULL)
222 *r = 0;
223 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
224 (parent != NULL && strlen(parent->path) >=
225 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
226 rs_free(p);
227 return (NULL);
228 }
229 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
230 if (anchor == NULL) {
231 rs_free(p);
232 return (NULL);
233 }
234 memset(anchor, 0, sizeof(*anchor));
235 RB_INIT(&anchor->children);
236 strlcpy(anchor->name, q, sizeof(anchor->name));
237 if (parent != NULL) {
238 strlcpy(anchor->path, parent->path,
239 sizeof(anchor->path));
240 strlcat(anchor->path, "/", sizeof(anchor->path));
241 }
242 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
243 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
244 NULL) {
245 printf("pf_find_or_create_ruleset: RB_INSERT1 "
246 "'%s' '%s' collides with '%s' '%s'\n",
247 anchor->path, anchor->name, dup->path, dup->name);
248 rs_free(anchor);
249 rs_free(p);
250 return (NULL);
251 }
252 if (parent != NULL) {
253 anchor->parent = parent;
254 if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
255 anchor)) != NULL) {
256 printf("pf_find_or_create_ruleset: "
257 "RB_INSERT2 '%s' '%s' collides with "
258 "'%s' '%s'\n", anchor->path, anchor->name,
259 dup->path, dup->name);
260 RB_REMOVE(pf_anchor_global, &pf_anchors,
261 anchor);
262 rs_free(anchor);
263 rs_free(p);
264 return (NULL);
265 }
266 }
267 pf_init_ruleset(&anchor->ruleset);
268 anchor->ruleset.anchor = anchor;
269 parent = anchor;
270 if (r != NULL)
271 q = r + 1;
272 else
273 *q = 0;
274 }
275 rs_free(p);
276 return (&anchor->ruleset);
277 }
278
279 void
pf_remove_if_empty_ruleset(struct pf_ruleset * ruleset)280 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
281 {
282 struct pf_anchor *parent;
283 int i;
284
285 while (ruleset != NULL) {
286 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
287 !RB_EMPTY(&ruleset->anchor->children) ||
288 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
289 ruleset->topen)
290 return;
291 for (i = 0; i < PF_RULESET_MAX; ++i)
292 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
293 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
294 ruleset->rules[i].inactive.open)
295 return;
296 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
297 if ((parent = ruleset->anchor->parent) != NULL)
298 RB_REMOVE(pf_anchor_node, &parent->children,
299 ruleset->anchor);
300 rs_free(ruleset->anchor);
301 if (parent == NULL)
302 return;
303 ruleset = &parent->ruleset;
304 }
305 }
306
307 int
pf_anchor_setup(struct pf_rule * r,const struct pf_ruleset * s,const char * name)308 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
309 const char *name)
310 {
311 char *p, *path;
312 struct pf_ruleset *ruleset;
313
314 r->anchor = NULL;
315 r->anchor_relative = 0;
316 r->anchor_wildcard = 0;
317 if (!name[0])
318 return (0);
319 path = (char *)rs_malloc(MAXPATHLEN);
320 bzero(path, MAXPATHLEN);
321 if (name[0] == '/')
322 strlcpy(path, name + 1, MAXPATHLEN);
323 else {
324 /* relative path */
325 r->anchor_relative = 1;
326 if (s->anchor == NULL || !s->anchor->path[0])
327 path[0] = 0;
328 else
329 strlcpy(path, s->anchor->path, MAXPATHLEN);
330 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
331 if (!path[0]) {
332 printf("pf_anchor_setup: .. beyond root\n");
333 rs_free(path);
334 return (1);
335 }
336 if ((p = strrchr(path, '/')) != NULL)
337 *p = 0;
338 else
339 path[0] = 0;
340 r->anchor_relative++;
341 name += 3;
342 }
343 if (path[0])
344 strlcat(path, "/", MAXPATHLEN);
345 strlcat(path, name, MAXPATHLEN);
346 }
347 if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
348 r->anchor_wildcard = 1;
349 *p = 0;
350 }
351 ruleset = pf_find_or_create_ruleset(path);
352 rs_free(path);
353 if (ruleset == NULL || ruleset->anchor == NULL) {
354 printf("pf_anchor_setup: ruleset\n");
355 return (1);
356 }
357 r->anchor = ruleset->anchor;
358 r->anchor->refcnt++;
359 return (0);
360 }
361
362 int
pf_anchor_copyout(const struct pf_ruleset * rs,const struct pf_rule * r,struct pfioc_rule * pr)363 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
364 struct pfioc_rule *pr)
365 {
366 pr->anchor_call[0] = 0;
367 if (r->anchor == NULL)
368 return (0);
369 if (!r->anchor_relative) {
370 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
371 strlcat(pr->anchor_call, r->anchor->path,
372 sizeof(pr->anchor_call));
373 } else {
374 char *a, *p;
375 int i;
376
377 a = (char *)rs_malloc(MAXPATHLEN);
378 bzero(a, MAXPATHLEN);
379 if (rs->anchor == NULL)
380 a[0] = 0;
381 else
382 strlcpy(a, rs->anchor->path, MAXPATHLEN);
383 for (i = 1; i < r->anchor_relative; ++i) {
384 if ((p = strrchr(a, '/')) == NULL)
385 p = a;
386 *p = 0;
387 strlcat(pr->anchor_call, "../",
388 sizeof(pr->anchor_call));
389 }
390 if (strncmp(a, r->anchor->path, strlen(a))) {
391 printf("pf_anchor_copyout: '%s' '%s'\n", a,
392 r->anchor->path);
393 rs_free(a);
394 return (1);
395 }
396 if (strlen(r->anchor->path) > strlen(a))
397 strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
398 strlen(a) + 1 : 0), sizeof(pr->anchor_call));
399 rs_free(a);
400 }
401 if (r->anchor_wildcard)
402 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
403 sizeof(pr->anchor_call));
404 return (0);
405 }
406
407 void
pf_anchor_remove(struct pf_rule * r)408 pf_anchor_remove(struct pf_rule *r)
409 {
410 if (r->anchor == NULL)
411 return;
412 if (r->anchor->refcnt <= 0) {
413 printf("pf_anchor_remove: broken refcount\n");
414 r->anchor = NULL;
415 return;
416 }
417 if (!--r->anchor->refcnt)
418 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
419 r->anchor = NULL;
420 }
421