1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
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 * $OpenBSD: pf_ruleset.c,v 1.2 2008/12/18 15:31:37 dhill Exp $
37 */
38
39 #include <sys/cdefs.h>
40 #include <sys/param.h>
41 #include <sys/socket.h>
42 #include <sys/systm.h>
43 #include <sys/refcount.h>
44 #include <sys/mbuf.h>
45
46 #include <netinet/in.h>
47 #include <netinet/in_systm.h>
48 #include <netinet/ip.h>
49 #include <netinet/tcp.h>
50
51 #include <net/if.h>
52 #include <net/vnet.h>
53 #include <net/pfvar.h>
54
55 #ifdef INET6
56 #include <netinet/ip6.h>
57 #endif /* INET6 */
58
59 #ifndef _KERNEL
60 #error "Kernel only file. Please use sbin/pfctl/pf_ruleset.c instead."
61 #endif
62
63 #define DPFPRINTF(format, x...) \
64 if (V_pf_status.debug >= PF_DEBUG_NOISY) \
65 printf(format , ##x)
66 #define rs_malloc(x) malloc(x, M_TEMP, M_NOWAIT|M_ZERO)
67 #define rs_free(x) free(x, M_TEMP)
68
69 VNET_DEFINE(struct pf_kanchor_global, pf_anchors);
70 VNET_DEFINE(struct pf_kanchor, pf_main_anchor);
71
72 static __inline int pf_kanchor_compare(struct pf_kanchor *,
73 struct pf_kanchor *);
74 static struct pf_kanchor *pf_find_kanchor(const char *);
75
76 RB_GENERATE(pf_kanchor_global, pf_kanchor, entry_global, pf_kanchor_compare);
77 RB_GENERATE(pf_kanchor_node, pf_kanchor, entry_node, pf_kanchor_compare);
78
79 static __inline int
pf_kanchor_compare(struct pf_kanchor * a,struct pf_kanchor * b)80 pf_kanchor_compare(struct pf_kanchor *a, struct pf_kanchor *b)
81 {
82 int c = strcmp(a->path, b->path);
83
84 return (c ? (c < 0 ? -1 : 1) : 0);
85 }
86
87 int
pf_get_ruleset_number(u_int8_t action)88 pf_get_ruleset_number(u_int8_t action)
89 {
90 switch (action) {
91 case PF_SCRUB:
92 case PF_NOSCRUB:
93 return (PF_RULESET_SCRUB);
94 break;
95 case PF_PASS:
96 case PF_MATCH:
97 case PF_DROP:
98 return (PF_RULESET_FILTER);
99 break;
100 case PF_NAT:
101 case PF_NONAT:
102 return (PF_RULESET_NAT);
103 break;
104 case PF_BINAT:
105 case PF_NOBINAT:
106 return (PF_RULESET_BINAT);
107 break;
108 case PF_RDR:
109 case PF_NORDR:
110 return (PF_RULESET_RDR);
111 break;
112 default:
113 return (PF_RULESET_MAX);
114 break;
115 }
116 }
117
118 static struct pf_kanchor *
pf_find_kanchor(const char * path)119 pf_find_kanchor(const char *path)
120 {
121 struct pf_kanchor *key, *found;
122
123 key = (struct pf_kanchor *)rs_malloc(sizeof(*key));
124 if (key == NULL)
125 return (NULL);
126 strlcpy(key->path, path, sizeof(key->path));
127 found = RB_FIND(pf_kanchor_global, &V_pf_anchors, key);
128 rs_free(key);
129 return (found);
130 }
131
132 void
pf_init_kruleset(struct pf_kruleset * ruleset)133 pf_init_kruleset(struct pf_kruleset *ruleset)
134 {
135 int i;
136
137 memset(ruleset, 0, sizeof(struct pf_kruleset));
138 for (i = 0; i < PF_RULESET_MAX; i++) {
139 TAILQ_INIT(&ruleset->rules[i].queues[0]);
140 TAILQ_INIT(&ruleset->rules[i].queues[1]);
141 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
142 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
143 }
144 }
145
146 struct pf_kruleset *
pf_find_kruleset(const char * path)147 pf_find_kruleset(const char *path)
148 {
149 struct pf_kanchor *anchor;
150
151 while (*path == '/')
152 path++;
153 if (!*path)
154 return (&pf_main_ruleset);
155 anchor = pf_find_kanchor(path);
156 if (anchor == NULL)
157 return (NULL);
158 else
159 return (&anchor->ruleset);
160 }
161
162 struct pf_kruleset *
pf_find_or_create_kruleset(const char * path)163 pf_find_or_create_kruleset(const char *path)
164 {
165 char *p, *q, *r;
166 struct pf_kruleset *ruleset;
167 struct pf_kanchor *anchor = NULL, *dup, *parent = NULL;
168
169 if (path[0] == 0)
170 return (&pf_main_ruleset);
171 while (*path == '/')
172 path++;
173 ruleset = pf_find_kruleset(path);
174 if (ruleset != NULL)
175 return (ruleset);
176 p = (char *)rs_malloc(MAXPATHLEN);
177 if (p == NULL)
178 return (NULL);
179 strlcpy(p, path, MAXPATHLEN);
180 while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
181 *q = 0;
182 if ((ruleset = pf_find_kruleset(p)) != NULL) {
183 parent = ruleset->anchor;
184 break;
185 }
186 }
187 if (q == NULL)
188 q = p;
189 else
190 q++;
191 strlcpy(p, path, MAXPATHLEN);
192 if (!*q) {
193 rs_free(p);
194 return (NULL);
195 }
196 while ((r = strchr(q, '/')) != NULL || *q) {
197 if (r != NULL)
198 *r = 0;
199 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
200 (parent != NULL && strlen(parent->path) >=
201 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
202 rs_free(p);
203 return (NULL);
204 }
205 anchor = (struct pf_kanchor *)rs_malloc(sizeof(*anchor));
206 if (anchor == NULL) {
207 rs_free(p);
208 return (NULL);
209 }
210 RB_INIT(&anchor->children);
211 strlcpy(anchor->name, q, sizeof(anchor->name));
212 if (parent != NULL) {
213 strlcpy(anchor->path, parent->path,
214 sizeof(anchor->path));
215 strlcat(anchor->path, "/", sizeof(anchor->path));
216 }
217 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
218 if ((dup = RB_INSERT(pf_kanchor_global, &V_pf_anchors, anchor)) !=
219 NULL) {
220 printf("pf_find_or_create_ruleset: RB_INSERT1 "
221 "'%s' '%s' collides with '%s' '%s'\n",
222 anchor->path, anchor->name, dup->path, dup->name);
223 rs_free(anchor);
224 rs_free(p);
225 return (NULL);
226 }
227 if (parent != NULL) {
228 anchor->parent = parent;
229 if ((dup = RB_INSERT(pf_kanchor_node, &parent->children,
230 anchor)) != NULL) {
231 printf("pf_find_or_create_ruleset: "
232 "RB_INSERT2 '%s' '%s' collides with "
233 "'%s' '%s'\n", anchor->path, anchor->name,
234 dup->path, dup->name);
235 RB_REMOVE(pf_kanchor_global, &V_pf_anchors,
236 anchor);
237 rs_free(anchor);
238 rs_free(p);
239 return (NULL);
240 }
241 }
242 pf_init_kruleset(&anchor->ruleset);
243 anchor->ruleset.anchor = anchor;
244 parent = anchor;
245 if (r != NULL)
246 q = r + 1;
247 else
248 *q = 0;
249 }
250 rs_free(p);
251 return (&anchor->ruleset);
252 }
253
254 void
pf_remove_if_empty_kruleset(struct pf_kruleset * ruleset)255 pf_remove_if_empty_kruleset(struct pf_kruleset *ruleset)
256 {
257 struct pf_kanchor *parent;
258 int i;
259
260 while (ruleset != NULL) {
261 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
262 !RB_EMPTY(&ruleset->anchor->children) ||
263 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
264 ruleset->topen)
265 return;
266 for (i = 0; i < PF_RULESET_MAX; ++i)
267 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
268 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
269 ruleset->rules[i].inactive.open)
270 return;
271 RB_REMOVE(pf_kanchor_global, &V_pf_anchors, ruleset->anchor);
272 if ((parent = ruleset->anchor->parent) != NULL)
273 RB_REMOVE(pf_kanchor_node, &parent->children,
274 ruleset->anchor);
275 rs_free(ruleset->anchor);
276 if (parent == NULL)
277 return;
278 ruleset = &parent->ruleset;
279 }
280 }
281
282 int
pf_kanchor_setup(struct pf_krule * r,const struct pf_kruleset * s,const char * name)283 pf_kanchor_setup(struct pf_krule *r, const struct pf_kruleset *s,
284 const char *name)
285 {
286 char *p, *path;
287 struct pf_kruleset *ruleset;
288
289 r->anchor = NULL;
290 r->anchor_relative = 0;
291 r->anchor_wildcard = 0;
292 if (!name[0])
293 return (0);
294 path = (char *)rs_malloc(MAXPATHLEN);
295 if (path == NULL)
296 return (1);
297 if (name[0] == '/')
298 strlcpy(path, name + 1, MAXPATHLEN);
299 else {
300 /* relative path */
301 r->anchor_relative = 1;
302 if (s->anchor == NULL || !s->anchor->path[0])
303 path[0] = 0;
304 else
305 strlcpy(path, s->anchor->path, MAXPATHLEN);
306 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
307 if (!path[0]) {
308 DPFPRINTF("pf_anchor_setup: .. beyond root\n");
309 rs_free(path);
310 return (1);
311 }
312 if ((p = strrchr(path, '/')) != NULL)
313 *p = 0;
314 else
315 path[0] = 0;
316 r->anchor_relative++;
317 name += 3;
318 }
319 if (path[0])
320 strlcat(path, "/", MAXPATHLEN);
321 strlcat(path, name, MAXPATHLEN);
322 }
323 if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
324 r->anchor_wildcard = 1;
325 *p = 0;
326 }
327 ruleset = pf_find_or_create_kruleset(path);
328 rs_free(path);
329 if (ruleset == NULL || ruleset->anchor == NULL) {
330 DPFPRINTF("pf_anchor_setup: ruleset\n");
331 return (1);
332 }
333 r->anchor = ruleset->anchor;
334 r->anchor->refcnt++;
335 return (0);
336 }
337
338 int
pf_kanchor_nvcopyout(const struct pf_kruleset * rs,const struct pf_krule * r,nvlist_t * nvl)339 pf_kanchor_nvcopyout(const struct pf_kruleset *rs, const struct pf_krule *r,
340 nvlist_t *nvl)
341 {
342 char anchor_call[MAXPATHLEN] = { 0 };
343
344 if (r->anchor == NULL)
345 goto done;
346 if (!r->anchor_relative) {
347 strlcpy(anchor_call, "/", sizeof(anchor_call));
348 strlcat(anchor_call, r->anchor->path,
349 sizeof(anchor_call));
350 } else {
351 char a[MAXPATHLEN];
352 char *p;
353 int i;
354 if (rs->anchor == NULL)
355 a[0] = 0;
356 else
357 strlcpy(a, rs->anchor->path, MAXPATHLEN);
358 for (i = 1; i < r->anchor_relative; ++i) {
359 if ((p = strrchr(a, '/')) == NULL)
360 p = a;
361 *p = 0;
362 strlcat(anchor_call, "../",
363 sizeof(anchor_call));
364 }
365 if (strncmp(a, r->anchor->path, strlen(a))) {
366 printf("pf_anchor_copyout: '%s' '%s'\n", a,
367 r->anchor->path);
368 return (1);
369 }
370 if (strlen(r->anchor->path) > strlen(a))
371 strlcat(anchor_call, r->anchor->path + (a[0] ?
372 strlen(a) + 1 : 0), sizeof(anchor_call));
373
374 }
375 if (r->anchor_wildcard)
376 strlcat(anchor_call, anchor_call[0] ? "/*" : "*",
377 sizeof(anchor_call));
378
379 done:
380 nvlist_add_string(nvl, "anchor_call", anchor_call);
381
382 return (0);
383 }
384
385 int
pf_kanchor_copyout(const struct pf_kruleset * rs,const struct pf_krule * r,struct pfioc_rule * pr)386 pf_kanchor_copyout(const struct pf_kruleset *rs, const struct pf_krule *r,
387 struct pfioc_rule *pr)
388 {
389 pr->anchor_call[0] = 0;
390 if (r->anchor == NULL)
391 return (0);
392 if (!r->anchor_relative) {
393 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
394 strlcat(pr->anchor_call, r->anchor->path,
395 sizeof(pr->anchor_call));
396 } else {
397 char *a, *p;
398 int i;
399
400 a = (char *)rs_malloc(MAXPATHLEN);
401 if (a == NULL)
402 return (1);
403 if (rs->anchor == NULL)
404 a[0] = 0;
405 else
406 strlcpy(a, rs->anchor->path, MAXPATHLEN);
407 for (i = 1; i < r->anchor_relative; ++i) {
408 if ((p = strrchr(a, '/')) == NULL)
409 p = a;
410 *p = 0;
411 strlcat(pr->anchor_call, "../",
412 sizeof(pr->anchor_call));
413 }
414 if (strncmp(a, r->anchor->path, strlen(a))) {
415 printf("pf_anchor_copyout: '%s' '%s'\n", a,
416 r->anchor->path);
417 rs_free(a);
418 return (1);
419 }
420 if (strlen(r->anchor->path) > strlen(a))
421 strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
422 strlen(a) + 1 : 0), sizeof(pr->anchor_call));
423 rs_free(a);
424 }
425 if (r->anchor_wildcard)
426 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
427 sizeof(pr->anchor_call));
428 return (0);
429 }
430
431 void
pf_kanchor_remove(struct pf_krule * r)432 pf_kanchor_remove(struct pf_krule *r)
433 {
434 if (r->anchor == NULL)
435 return;
436 if (r->anchor->refcnt <= 0) {
437 printf("pf_anchor_remove: broken refcount\n");
438 r->anchor = NULL;
439 return;
440 }
441 if (!--r->anchor->refcnt)
442 pf_remove_if_empty_kruleset(&r->anchor->ruleset);
443 r->anchor = NULL;
444 }
445