1/* $OpenBSD: pf_ruleset.c,v 1.1 2006/10/27 13:56:51 mcbride Exp $ */
2
3/*
4 * Copyright (c) 2001 Daniel Hartmeier
5 * Copyright (c) 2002,2003 Henning Brauer
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 *
12 * - Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * - Redistributions in binary form must reproduce the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer in the documentation and/or other materials provided
17 * with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
23 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
27 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
29 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 *
32 * Effort sponsored in part by the Defense Advanced Research Projects
33 * Agency (DARPA) and Air Force Research Laboratory, Air Force
34 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
35 *
36 */
37
38#ifdef __FreeBSD__
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: head/sys/contrib/pf/net/pf_ruleset.c 171168 2007-07-03 12:16:07Z mlaier $");
41#endif
42
43#include <sys/param.h>
44#include <sys/socket.h>
45#ifdef _KERNEL
46# include <sys/systm.h>
47#endif /* _KERNEL */
48#include <sys/mbuf.h>
49
50#include <netinet/in.h>
51#include <netinet/in_systm.h>
52#include <netinet/ip.h>
53#include <netinet/tcp.h>
54
55#include <net/if.h>
56#include <net/pfvar.h>
57
58#ifdef INET6
59#include <netinet/ip6.h>
60#endif /* INET6 */
61
62
63#ifdef _KERNEL
64# define DPFPRINTF(format, x...) \
65 if (pf_status.debug >= PF_DEBUG_NOISY) \
66 printf(format , ##x)
67#ifdef __FreeBSD__
68#define rs_malloc(x) malloc(x, M_TEMP, M_NOWAIT)
69#else
70#define rs_malloc(x) malloc(x, M_TEMP, M_WAITOK)
71#endif
72#define rs_free(x) free(x, M_TEMP)
73
74#else
75/* Userland equivalents so we can lend code to pfctl et al. */
76
77# include <arpa/inet.h>
78# include <errno.h>
79# include <stdio.h>
80# include <stdlib.h>
81# include <string.h>
82# define rs_malloc(x) malloc(x)
83# define rs_free(x) free(x)
84
85# ifdef PFDEBUG
86# include <sys/stdarg.h>
87# define DPFPRINTF(format, x...) fprintf(stderr, format , ##x)
88# else
89# define DPFPRINTF(format, x...) ((void)0)
90# endif /* PFDEBUG */
91#endif /* _KERNEL */
92
93
94struct pf_anchor_global pf_anchors;
95struct pf_anchor pf_main_anchor;
96
97#ifndef __FreeBSD__
98/* XXX: hum? */
99int pf_get_ruleset_number(u_int8_t);
100void pf_init_ruleset(struct pf_ruleset *);
101int pf_anchor_setup(struct pf_rule *,
102 const struct pf_ruleset *, const char *);
103int pf_anchor_copyout(const struct pf_ruleset *,
104 const struct pf_rule *, struct pfioc_rule *);
105void pf_anchor_remove(struct pf_rule *);
106#endif
107
108static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
109
110RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
111RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
112
113static __inline int
114pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
115{
116 int c = strcmp(a->path, b->path);
117
118 return (c ? (c < 0 ? -1 : 1) : 0);
119}
120
121int
122pf_get_ruleset_number(u_int8_t action)
123{
124 switch (action) {
125 case PF_SCRUB:
126 case PF_NOSCRUB:
127 return (PF_RULESET_SCRUB);
128 break;
129 case PF_PASS:
130 case PF_DROP:
131 return (PF_RULESET_FILTER);
132 break;
133 case PF_NAT:
134 case PF_NONAT:
135 return (PF_RULESET_NAT);
136 break;
137 case PF_BINAT:
138 case PF_NOBINAT:
139 return (PF_RULESET_BINAT);
140 break;
141 case PF_RDR:
142 case PF_NORDR:
143 return (PF_RULESET_RDR);
144 break;
145 default:
146 return (PF_RULESET_MAX);
147 break;
148 }
149}
150
151void
152pf_init_ruleset(struct pf_ruleset *ruleset)
153{
154 int i;
155
156 memset(ruleset, 0, sizeof(struct pf_ruleset));
157 for (i = 0; i < PF_RULESET_MAX; i++) {
158 TAILQ_INIT(&ruleset->rules[i].queues[0]);
159 TAILQ_INIT(&ruleset->rules[i].queues[1]);
160 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
161 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
162 }
163}
164
165struct pf_anchor *
166pf_find_anchor(const char *path)
167{
168 struct pf_anchor *key, *found;
169
170 key = (struct pf_anchor *)rs_malloc(sizeof(*key));
171 memset(key, 0, sizeof(*key));
172 strlcpy(key->path, path, sizeof(key->path));
173 found = RB_FIND(pf_anchor_global, &pf_anchors, key);
174 rs_free(key);
175 return (found);
176}
177
178struct pf_ruleset *
179pf_find_ruleset(const char *path)
180{
181 struct pf_anchor *anchor;
182
183 while (*path == '/')
184 path++;
185 if (!*path)
186 return (&pf_main_ruleset);
187 anchor = pf_find_anchor(path);
188 if (anchor == NULL)
189 return (NULL);
190 else
191 return (&anchor->ruleset);
192}
193
194struct pf_ruleset *
195pf_find_or_create_ruleset(const char *path)
196{
197 char *p, *q, *r;
198 struct pf_ruleset *ruleset;
199#ifdef __FreeBSD__
200 struct pf_anchor *anchor = NULL, *dup, *parent = NULL;
201#else
202 struct pf_anchor *anchor, *dup, *parent = NULL;
203#endif
204
205 if (path[0] == 0)
206 return (&pf_main_ruleset);
207 while (*path == '/')
208 path++;
209 ruleset = pf_find_ruleset(path);
210 if (ruleset != NULL)
211 return (ruleset);
212 p = (char *)rs_malloc(MAXPATHLEN);
213 bzero(p, MAXPATHLEN);
214 strlcpy(p, path, MAXPATHLEN);
215 while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
216 *q = 0;
217 if ((ruleset = pf_find_ruleset(p)) != NULL) {
218 parent = ruleset->anchor;
219 break;
220 }
221 }
222 if (q == NULL)
223 q = p;
224 else
225 q++;
226 strlcpy(p, path, MAXPATHLEN);
227 if (!*q) {
228 rs_free(p);
229 return (NULL);
230 }
231 while ((r = strchr(q, '/')) != NULL || *q) {
232 if (r != NULL)
233 *r = 0;
234 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
235 (parent != NULL && strlen(parent->path) >=
236 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
237 rs_free(p);
238 return (NULL);
239 }
240 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
241 if (anchor == NULL) {
242 rs_free(p);
243 return (NULL);
244 }
245 memset(anchor, 0, sizeof(*anchor));
246 RB_INIT(&anchor->children);
247 strlcpy(anchor->name, q, sizeof(anchor->name));
248 if (parent != NULL) {
249 strlcpy(anchor->path, parent->path,
250 sizeof(anchor->path));
251 strlcat(anchor->path, "/", sizeof(anchor->path));
252 }
253 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
254 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
255 NULL) {
256 printf("pf_find_or_create_ruleset: RB_INSERT1 "
257 "'%s' '%s' collides with '%s' '%s'\n",
258 anchor->path, anchor->name, dup->path, dup->name);
259 rs_free(anchor);
260 rs_free(p);
261 return (NULL);
262 }
263 if (parent != NULL) {
264 anchor->parent = parent;
265 if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
266 anchor)) != NULL) {
267 printf("pf_find_or_create_ruleset: "
268 "RB_INSERT2 '%s' '%s' collides with "
269 "'%s' '%s'\n", anchor->path, anchor->name,
270 dup->path, dup->name);
271 RB_REMOVE(pf_anchor_global, &pf_anchors,
272 anchor);
273 rs_free(anchor);
274 rs_free(p);
275 return (NULL);
276 }
277 }
278 pf_init_ruleset(&anchor->ruleset);
279 anchor->ruleset.anchor = anchor;
280 parent = anchor;
281 if (r != NULL)
282 q = r + 1;
283 else
284 *q = 0;
285 }
286 rs_free(p);
287 return (&anchor->ruleset);
288}
289
290void
291pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
292{
293 struct pf_anchor *parent;
294 int i;
295
296 while (ruleset != NULL) {
297 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
298 !RB_EMPTY(&ruleset->anchor->children) ||
299 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
300 ruleset->topen)
301 return;
302 for (i = 0; i < PF_RULESET_MAX; ++i)
303 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
304 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
305 ruleset->rules[i].inactive.open)
306 return;
307 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
308 if ((parent = ruleset->anchor->parent) != NULL)
309 RB_REMOVE(pf_anchor_node, &parent->children,
310 ruleset->anchor);
311 rs_free(ruleset->anchor);
312 if (parent == NULL)
313 return;
314 ruleset = &parent->ruleset;
315 }
316}
317
318int
319pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
320 const char *name)
321{
322 char *p, *path;
323 struct pf_ruleset *ruleset;
324
325 r->anchor = NULL;
326 r->anchor_relative = 0;
327 r->anchor_wildcard = 0;
328 if (!name[0])
329 return (0);
330 path = (char *)rs_malloc(MAXPATHLEN);
331 bzero(path, MAXPATHLEN);
332 if (name[0] == '/')
333 strlcpy(path, name + 1, MAXPATHLEN);
334 else {
335 /* relative path */
336 r->anchor_relative = 1;
337 if (s->anchor == NULL || !s->anchor->path[0])
338 path[0] = 0;
339 else
340 strlcpy(path, s->anchor->path, MAXPATHLEN);
341 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
342 if (!path[0]) {
343 printf("pf_anchor_setup: .. beyond root\n");
344 rs_free(path);
345 return (1);
346 }
347 if ((p = strrchr(path, '/')) != NULL)
348 *p = 0;
349 else
350 path[0] = 0;
351 r->anchor_relative++;
352 name += 3;
353 }
354 if (path[0])
355 strlcat(path, "/", MAXPATHLEN);
356 strlcat(path, name, MAXPATHLEN);
357 }
358 if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
359 r->anchor_wildcard = 1;
360 *p = 0;
361 }
362 ruleset = pf_find_or_create_ruleset(path);
363 rs_free(path);
364 if (ruleset == NULL || ruleset->anchor == NULL) {
365 printf("pf_anchor_setup: ruleset\n");
366 return (1);
367 }
368 r->anchor = ruleset->anchor;
369 r->anchor->refcnt++;
370 return (0);
371}
372
373int
374pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
375 struct pfioc_rule *pr)
376{
377 pr->anchor_call[0] = 0;
378 if (r->anchor == NULL)
379 return (0);
380 if (!r->anchor_relative) {
381 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
382 strlcat(pr->anchor_call, r->anchor->path,
383 sizeof(pr->anchor_call));
384 } else {
385 char *a, *p;
386 int i;
387
388 a = (char *)rs_malloc(MAXPATHLEN);
389 bzero(a, MAXPATHLEN);
390 if (rs->anchor == NULL)
391 a[0] = 0;
392 else
393 strlcpy(a, rs->anchor->path, MAXPATHLEN);
394 for (i = 1; i < r->anchor_relative; ++i) {
395 if ((p = strrchr(a, '/')) == NULL)
396 p = a;
397 *p = 0;
398 strlcat(pr->anchor_call, "../",
399 sizeof(pr->anchor_call));
400 }
401 if (strncmp(a, r->anchor->path, strlen(a))) {
402 printf("pf_anchor_copyout: '%s' '%s'\n", a,
403 r->anchor->path);
404 rs_free(a);
405 return (1);
406 }
407 if (strlen(r->anchor->path) > strlen(a))
408 strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
409 strlen(a) + 1 : 0), sizeof(pr->anchor_call));
410 rs_free(a);
411 }
412 if (r->anchor_wildcard)
413 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
414 sizeof(pr->anchor_call));
415 return (0);
416}
417
418void
419pf_anchor_remove(struct pf_rule *r)
420{
421 if (r->anchor == NULL)
422 return;
423 if (r->anchor->refcnt <= 0) {
424 printf("pf_anchor_remove: broken refcount\n");
425 r->anchor = NULL;
426 return;
427 }
428 if (!--r->anchor->refcnt)
429 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
430 r->anchor = NULL;
431}