1 /*
2 * Copyright (c) 2007-2021 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29 /* $apfw: pf_ruleset.c,v 1.2 2007/08/10 03:00:16 jhw Exp $ */
30 /* $OpenBSD: pf_ruleset.c,v 1.1 2006/10/27 13:56:51 mcbride Exp $ */
31
32 /*
33 * Copyright (c) 2001 Daniel Hartmeier
34 * Copyright (c) 2002,2003 Henning Brauer
35 * NAT64 - Copyright (c) 2010 Viagenie Inc. (http://www.viagenie.ca)
36 * All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 *
42 * - Redistributions of source code must retain the above copyright
43 * notice, this list of conditions and the following disclaimer.
44 * - Redistributions in binary form must reproduce the above
45 * copyright notice, this list of conditions and the following
46 * disclaimer in the documentation and/or other materials provided
47 * with the distribution.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
50 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
51 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
52 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
53 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
54 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
55 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
56 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
57 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
58 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
59 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
60 * POSSIBILITY OF SUCH DAMAGE.
61 *
62 * Effort sponsored in part by the Defense Advanced Research Projects
63 * Agency (DARPA) and Air Force Research Laboratory, Air Force
64 * Materiel Command, USAF, under agreement number F30602-01-2-0537.
65 *
66 */
67
68 #include <sys/param.h>
69 #include <sys/socket.h>
70 #ifdef KERNEL
71 #include <sys/systm.h>
72 #include <sys/malloc.h>
73 #include <libkern/libkern.h>
74 #endif /* KERNEL */
75 #include <sys/mbuf.h>
76
77 #include <netinet/ip_dummynet.h>
78 #include <netinet/in.h>
79 #include <netinet/in_systm.h>
80 #include <netinet/ip.h>
81 #include <netinet/tcp.h>
82
83 #include <net/if.h>
84 #include <net/pfvar.h>
85
86 #include <netinet/ip6.h>
87
88
89 #ifdef KERNEL
90 #define DPFPRINTF(format, x ...) \
91 if (pf_status.debug >= PF_DEBUG_NOISY) \
92 printf(format, ##x)
93 #define rs_malloc_data(size) kalloc_data(size, Z_WAITOK)
94 #define rs_malloc_type(type) kalloc_type(type, Z_WAITOK | Z_ZERO)
95 #define rs_free_data kfree_data
96 #define rs_free_type kfree_type
97
98 #else
99 /* Userland equivalents so we can lend code to pfctl et al. */
100
101 #include <arpa/inet.h>
102 #include <errno.h>
103 #include <stdio.h>
104 #include <stdlib.h>
105 #include <string.h>
106 static __inline void*
rs_malloc_data(size_t size)107 rs_malloc_data(size_t size)
108 {
109 void* result = malloc(size);
110 if (result != NULL) {
111 memset(result, 0, size);
112 }
113 return result;
114 }
115 #define rs_malloc_type(type) ((type*) rs_malloc_data(sizeof(type)))
116 #define rs_free_data(ptr, size) free(ptr)
117 #define rs_free_type(type, ptr) free(ptr)
118
119 #ifdef PFDEBUG
120 #include <sys/stdarg.h>
121 #define DPFPRINTF(format, x...) fprintf(stderr, format, ##x)
122 #else
123 #define DPFPRINTF(format, x...) ((void)0)
124 #endif /* PFDEBUG */
125 #endif /* KERNEL */
126
127
128 struct pf_anchor_global pf_anchors;
129 struct pf_anchor pf_main_anchor;
130
131 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
132
133 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
134 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
135
136 static __inline int
pf_anchor_compare(struct pf_anchor * a,struct pf_anchor * b)137 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
138 {
139 int c = strcmp(a->path, b->path);
140
141 return c ? (c < 0 ? -1 : 1) : 0;
142 }
143
144 int
pf_get_ruleset_number(u_int8_t action)145 pf_get_ruleset_number(u_int8_t action)
146 {
147 switch (action) {
148 case PF_SCRUB:
149 case PF_NOSCRUB:
150 return PF_RULESET_SCRUB;
151 case PF_PASS:
152 case PF_DROP:
153 return PF_RULESET_FILTER;
154 case PF_NAT:
155 case PF_NONAT:
156 return PF_RULESET_NAT;
157 case PF_BINAT:
158 case PF_NOBINAT:
159 return PF_RULESET_BINAT;
160 case PF_RDR:
161 case PF_NORDR:
162 case PF_NAT64:
163 case PF_NONAT64:
164 return PF_RULESET_RDR;
165 #if DUMMYNET
166 case PF_DUMMYNET:
167 case PF_NODUMMYNET:
168 return PF_RULESET_DUMMYNET;
169 #endif /* DUMMYNET */
170 default:
171 return PF_RULESET_MAX;
172 }
173 }
174
175 void
pf_init_ruleset(struct pf_ruleset * ruleset)176 pf_init_ruleset(struct pf_ruleset *ruleset)
177 {
178 int i;
179
180 memset(ruleset, 0, sizeof(struct pf_ruleset));
181 for (i = 0; i < PF_RULESET_MAX; i++) {
182 TAILQ_INIT(&ruleset->rules[i].queues[0]);
183 TAILQ_INIT(&ruleset->rules[i].queues[1]);
184 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
185 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
186 }
187 }
188
189 struct pf_anchor *
pf_find_anchor(const char * path)190 pf_find_anchor(const char *path)
191 {
192 struct pf_anchor *key, *found;
193
194 key = rs_malloc_type(struct pf_anchor);
195 strlcpy(key->path, path, sizeof(key->path));
196 found = RB_FIND(pf_anchor_global, &pf_anchors, key);
197 rs_free_type(struct pf_anchor, key);
198 return found;
199 }
200
201 struct pf_ruleset *
pf_find_ruleset(const char * path)202 pf_find_ruleset(const char *path)
203 {
204 struct pf_anchor *anchor;
205
206 while (*path == '/') {
207 path++;
208 }
209 if (!*path) {
210 return &pf_main_ruleset;
211 }
212 anchor = pf_find_anchor(path);
213 if (anchor == NULL) {
214 return NULL;
215 } else {
216 return &anchor->ruleset;
217 }
218 }
219
220 struct pf_ruleset *
pf_find_ruleset_with_owner(const char * path,const char * owner,int is_anchor,int * error)221 pf_find_ruleset_with_owner(const char *path, const char *owner, int is_anchor,
222 int *error)
223 {
224 struct pf_anchor *anchor;
225
226 while (*path == '/') {
227 path++;
228 }
229 if (!*path) {
230 return &pf_main_ruleset;
231 }
232 anchor = pf_find_anchor(path);
233 if (anchor == NULL) {
234 *error = EINVAL;
235 return NULL;
236 } else {
237 if ((owner && (!strcmp(owner, anchor->owner)))
238 || (is_anchor && !strcmp(anchor->owner, ""))) {
239 return &anchor->ruleset;
240 }
241 *error = EPERM;
242 return NULL;
243 }
244 }
245
246 struct pf_ruleset *
pf_find_or_create_ruleset(const char * path)247 pf_find_or_create_ruleset(const char *path)
248 {
249 char *p, *q = NULL, *r;
250 struct pf_ruleset *ruleset;
251 struct pf_anchor *anchor = 0, *dup, *parent = NULL;
252
253 if (path[0] == 0) {
254 return &pf_main_ruleset;
255 }
256 while (*path == '/') {
257 path++;
258 }
259 ruleset = pf_find_ruleset(path);
260 if (ruleset != NULL) {
261 return ruleset;
262 }
263 p = (char *)rs_malloc_data(MAXPATHLEN);
264 strlcpy(p, path, MAXPATHLEN);
265 while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
266 *q = 0;
267 if ((ruleset = pf_find_ruleset(p)) != NULL) {
268 parent = ruleset->anchor;
269 break;
270 }
271 }
272 if (q == NULL) {
273 q = p;
274 } else {
275 q++;
276 }
277 strlcpy(p, path, MAXPATHLEN);
278 if (!*q) {
279 rs_free_data(p, MAXPATHLEN);
280 return NULL;
281 }
282 while ((r = strchr(q, '/')) != NULL || *q) {
283 if (r != NULL) {
284 *r = 0;
285 }
286 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
287 (parent != NULL && strlen(parent->path) >=
288 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
289 rs_free_data(p, MAXPATHLEN);
290 return NULL;
291 }
292 anchor = rs_malloc_type(struct pf_anchor);
293 if (anchor == NULL) {
294 rs_free_data(p, MAXPATHLEN);
295 return NULL;
296 }
297 RB_INIT(&anchor->children);
298 strlcpy(anchor->name, q, sizeof(anchor->name));
299 if (parent != NULL) {
300 strlcpy(anchor->path, parent->path,
301 sizeof(anchor->path));
302 strlcat(anchor->path, "/", sizeof(anchor->path));
303 }
304 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
305 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
306 NULL) {
307 printf("pf_find_or_create_ruleset: RB_INSERT1 "
308 "'%s' '%s' collides with '%s' '%s'\n",
309 anchor->path, anchor->name, dup->path, dup->name);
310 rs_free_type(struct pf_anchor, anchor);
311 rs_free_data(p, MAXPATHLEN);
312 return NULL;
313 }
314 if (parent != NULL) {
315 anchor->parent = parent;
316 if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
317 anchor)) != NULL) {
318 printf("pf_find_or_create_ruleset: "
319 "RB_INSERT2 '%s' '%s' collides with "
320 "'%s' '%s'\n", anchor->path, anchor->name,
321 dup->path, dup->name);
322 RB_REMOVE(pf_anchor_global, &pf_anchors,
323 anchor);
324 rs_free_type(struct pf_anchor, anchor);
325 rs_free_data(p, MAXPATHLEN);
326 return NULL;
327 }
328 }
329 pf_init_ruleset(&anchor->ruleset);
330 anchor->ruleset.anchor = anchor;
331 parent = anchor;
332 if (r != NULL) {
333 q = r + 1;
334 } else {
335 *q = 0;
336 }
337 #if DUMMYNET
338 if (strncmp("com.apple.nlc", anchor->name,
339 sizeof("com.apple.nlc")) == 0) {
340 is_nlc_enabled_glb = TRUE;
341 }
342 #endif
343 }
344 rs_free_data(p, MAXPATHLEN);
345 return anchor ? &anchor->ruleset : 0;
346 }
347
348 void
pf_remove_if_empty_ruleset(struct pf_ruleset * ruleset)349 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
350 {
351 struct pf_anchor *parent;
352 int i;
353
354 while (ruleset != NULL) {
355 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
356 !RB_EMPTY(&ruleset->anchor->children) ||
357 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
358 ruleset->topen) {
359 return;
360 }
361 for (i = 0; i < PF_RULESET_MAX; ++i) {
362 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
363 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
364 ruleset->rules[i].inactive.open) {
365 return;
366 }
367 }
368 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
369 #if DUMMYNET
370 if (strncmp("com.apple.nlc", ruleset->anchor->name,
371 sizeof("com.apple.nlc")) == 0) {
372 struct dummynet_event dn_event;
373 bzero(&dn_event, sizeof(dn_event));
374 dn_event.dn_event_code = DUMMYNET_NLC_DISABLED;
375 dummynet_event_enqueue_nwk_wq_entry(&dn_event);
376 is_nlc_enabled_glb = FALSE;
377 }
378 #endif
379 if ((parent = ruleset->anchor->parent) != NULL) {
380 RB_REMOVE(pf_anchor_node, &parent->children,
381 ruleset->anchor);
382 }
383 rs_free_type(struct pf_anchor, ruleset->anchor);
384 if (parent == NULL) {
385 return;
386 }
387 ruleset = &parent->ruleset;
388 }
389 }
390
391 int
pf_anchor_setup(struct pf_rule * r,const struct pf_ruleset * s,const char * name)392 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
393 const char *name)
394 {
395 char *p, *path;
396 struct pf_ruleset *ruleset;
397
398 r->anchor = NULL;
399 r->anchor_relative = 0;
400 r->anchor_wildcard = 0;
401 if (!name[0]) {
402 return 0;
403 }
404 path = (char *)rs_malloc_data(MAXPATHLEN);
405 if (name[0] == '/') {
406 strlcpy(path, name + 1, MAXPATHLEN);
407 } else {
408 /* relative path */
409 r->anchor_relative = 1;
410 if (s->anchor == NULL || !s->anchor->path[0]) {
411 path[0] = 0;
412 } else {
413 strlcpy(path, s->anchor->path, MAXPATHLEN);
414 }
415 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
416 if (!path[0]) {
417 printf("pf_anchor_setup: .. beyond root\n");
418 rs_free_data(path, MAXPATHLEN);
419 return 1;
420 }
421 if ((p = strrchr(path, '/')) != NULL) {
422 *p = 0;
423 } else {
424 path[0] = 0;
425 }
426 r->anchor_relative++;
427 name += 3;
428 }
429 if (path[0]) {
430 strlcat(path, "/", MAXPATHLEN);
431 }
432 strlcat(path, name, MAXPATHLEN);
433 }
434 if ((p = strrchr(path, '/')) != NULL && strcmp(p, "/*") == 0) {
435 r->anchor_wildcard = 1;
436 *p = 0;
437 }
438 ruleset = pf_find_or_create_ruleset(path);
439 rs_free_data(path, MAXPATHLEN);
440 if (ruleset == NULL || ruleset->anchor == NULL) {
441 printf("pf_anchor_setup: ruleset\n");
442 return 1;
443 }
444 r->anchor = ruleset->anchor;
445 r->anchor->refcnt++;
446 return 0;
447 }
448
449 int
pf_anchor_copyout(const struct pf_ruleset * rs,const struct pf_rule * r,struct pfioc_rule * pr)450 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
451 struct pfioc_rule *pr)
452 {
453 pr->anchor_call[0] = 0;
454 if (r->anchor == NULL) {
455 return 0;
456 }
457 if (!r->anchor_relative) {
458 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
459 strlcat(pr->anchor_call, r->anchor->path,
460 sizeof(pr->anchor_call));
461 } else {
462 char *a, *p;
463 int i;
464
465 a = (char *)rs_malloc_data(MAXPATHLEN);
466 if (rs->anchor == NULL) {
467 a[0] = 0;
468 } else {
469 strlcpy(a, rs->anchor->path, MAXPATHLEN);
470 }
471 for (i = 1; i < r->anchor_relative; ++i) {
472 if ((p = strrchr(a, '/')) == NULL) {
473 p = a;
474 }
475 *p = 0;
476 strlcat(pr->anchor_call, "../",
477 sizeof(pr->anchor_call));
478 }
479 if (strncmp(a, r->anchor->path, strlen(a))) {
480 printf("pf_anchor_copyout: '%s' '%s'\n", a,
481 r->anchor->path);
482 rs_free_data(a, MAXPATHLEN);
483 return 1;
484 }
485 if (strlen(r->anchor->path) > strlen(a)) {
486 strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
487 strlen(a) + 1 : 0), sizeof(pr->anchor_call));
488 }
489 rs_free_data(a, MAXPATHLEN);
490 }
491 if (r->anchor_wildcard) {
492 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
493 sizeof(pr->anchor_call));
494 }
495 return 0;
496 }
497
498 void
pf_anchor_remove(struct pf_rule * r)499 pf_anchor_remove(struct pf_rule *r)
500 {
501 if (r->anchor == NULL) {
502 return;
503 }
504 if (r->anchor->refcnt <= 0) {
505 printf("pf_anchor_remove: broken refcount\n");
506 r->anchor = NULL;
507 return;
508 }
509 if (!--r->anchor->refcnt) {
510 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
511 }
512 r->anchor = NULL;
513 }
514