bsd/net/pf_ruleset.c

   1 /*
   2  * Copyright (c) 2007-2016 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(x)            _MALLOC(x, M_TEMP, M_WAITOK)
  94 #define rs_free(x)              _FREE(x, M_TEMP)
  95
  96 #else
  97 /* Userland equivalents so we can lend code to pfctl et al. */
  98
  99 #include <arpa/inet.h>
 100 #include <errno.h>
 101 #include <stdio.h>
 102 #include <stdlib.h>
 103 #include <string.h>
 104 #define rs_malloc(x)             malloc(x)
 105 #define rs_free(x)               free(x)
 106
 107 #ifdef PFDEBUG
 108 #include <sys/stdarg.h>
 109 #define DPFPRINTF(format, x...) fprintf(stderr, format, ##x)
 110 #else
 111 #define DPFPRINTF(format, x...) ((void)0)
 112 #endif /* PFDEBUG */
 113 #endif /* KERNEL */
 114
 115
 116 struct pf_anchor_global  pf_anchors;
 117 struct pf_anchor         pf_main_anchor;
 118
 119 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
 120
 121 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
 122 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
 123
 124 static __inline int
 125 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
 126 {
 127         int c = strcmp(a->path, b->path);
 128
 129         return c ? (c < 0 ? -1 : 1) : 0;
 130 }
 131
 132 int
 133 pf_get_ruleset_number(u_int8_t action)
 134 {
 135         switch (action) {
 136         case PF_SCRUB:
 137         case PF_NOSCRUB:
 138                 return PF_RULESET_SCRUB;
 139         case PF_PASS:
 140         case PF_DROP:
 141                 return PF_RULESET_FILTER;
 142         case PF_NAT:
 143         case PF_NONAT:
 144                 return PF_RULESET_NAT;
 145         case PF_BINAT:
 146         case PF_NOBINAT:
 147                 return PF_RULESET_BINAT;
 148         case PF_RDR:
 149         case PF_NORDR:
 150         case PF_NAT64:
 151         case PF_NONAT64:
 152                 return PF_RULESET_RDR;
 153 #if DUMMYNET
 154         case PF_DUMMYNET:
 155         case PF_NODUMMYNET:
 156                 return PF_RULESET_DUMMYNET;
 157 #endif /* DUMMYNET */
 158         default:
 159                 return PF_RULESET_MAX;
 160         }
 161 }
 162
 163 void
 164 pf_init_ruleset(struct pf_ruleset *ruleset)
 165 {
 166         int     i;
 167
 168         memset(ruleset, 0, sizeof(struct pf_ruleset));
 169         for (i = 0; i < PF_RULESET_MAX; i++) {
 170                 TAILQ_INIT(&ruleset->rules[i].queues[0]);
 171                 TAILQ_INIT(&ruleset->rules[i].queues[1]);
 172                 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
 173                 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
 174         }
 175 }
 176
 177 struct pf_anchor *
 178 pf_find_anchor(const char *path)
 179 {
 180         struct pf_anchor        *key, *found;
 181
 182         key = (struct pf_anchor *)rs_malloc(sizeof(*key));
 183         memset(key, 0, sizeof(*key));
 184         strlcpy(key->path, path, sizeof(key->path));
 185         found = RB_FIND(pf_anchor_global, &pf_anchors, key);
 186         rs_free(key);
 187         return found;
 188 }
 189
 190 struct pf_ruleset *
 191 pf_find_ruleset(const char *path)
 192 {
 193         struct pf_anchor        *anchor;
 194
 195         while (*path == '/') {
 196                 path++;
 197         }
 198         if (!*path) {
 199                 return &pf_main_ruleset;
 200         }
 201         anchor = pf_find_anchor(path);
 202         if (anchor == NULL) {
 203                 return NULL;
 204         } else {
 205                 return &anchor->ruleset;
 206         }
 207 }
 208
 209 struct pf_ruleset *
 210 pf_find_ruleset_with_owner(const char *path, const char *owner, int is_anchor,
 211     int *error)
 212 {
 213         struct pf_anchor        *anchor;
 214
 215         while (*path == '/') {
 216                 path++;
 217         }
 218         if (!*path) {
 219                 return &pf_main_ruleset;
 220         }
 221         anchor = pf_find_anchor(path);
 222         if (anchor == NULL) {
 223                 *error = EINVAL;
 224                 return NULL;
 225         } else {
 226                 if ((owner && (!strcmp(owner, anchor->owner)))
 227                     || (is_anchor && !strcmp(anchor->owner, ""))) {
 228                         return &anchor->ruleset;
 229                 }
 230                 *error = EPERM;
 231                 return NULL;
 232         }
 233 }
 234
 235 struct pf_ruleset *
 236 pf_find_or_create_ruleset(const char *path)
 237 {
 238         char                    *p, *q = NULL, *r;
 239         struct pf_ruleset       *ruleset;
 240         struct pf_anchor        *anchor = 0, *dup, *parent = NULL;
 241
 242         if (path[0] == 0) {
 243                 return &pf_main_ruleset;
 244         }
 245         while (*path == '/') {
 246                 path++;
 247         }
 248         ruleset = pf_find_ruleset(path);
 249         if (ruleset != NULL) {
 250                 return ruleset;
 251         }
 252         p = (char *)rs_malloc(MAXPATHLEN);
 253         bzero(p, MAXPATHLEN);
 254         strlcpy(p, path, MAXPATHLEN);
 255         while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
 256                 *q = 0;
 257                 if ((ruleset = pf_find_ruleset(p)) != NULL) {
 258                         parent = ruleset->anchor;
 259                         break;
 260                 }
 261         }
 262         if (q == NULL) {
 263                 q = p;
 264         } else {
 265                 q++;
 266         }
 267         strlcpy(p, path, MAXPATHLEN);
 268         if (!*q) {
 269                 rs_free(p);
 270                 return NULL;
 271         }
 272         while ((r = strchr(q, '/')) != NULL || *q) {
 273                 if (r != NULL) {
 274                         *r = 0;
 275                 }
 276                 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
 277                     (parent != NULL && strlen(parent->path) >=
 278                     MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
 279                         rs_free(p);
 280                         return NULL;
 281                 }
 282                 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
 283                 if (anchor == NULL) {
 284                         rs_free(p);
 285                         return NULL;
 286                 }
 287                 memset(anchor, 0, sizeof(*anchor));
 288                 RB_INIT(&anchor->children);
 289                 strlcpy(anchor->name, q, sizeof(anchor->name));
 290                 if (parent != NULL) {
 291                         strlcpy(anchor->path, parent->path,
 292                             sizeof(anchor->path));
 293                         strlcat(anchor->path, "/", sizeof(anchor->path));
 294                 }
 295                 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
 296                 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
 297                     NULL) {
 298                         printf("pf_find_or_create_ruleset: RB_INSERT1 "
 299                             "'%s' '%s' collides with '%s' '%s'\n",
 300                             anchor->path, anchor->name, dup->path, dup->name);
 301                         rs_free(anchor);
 302                         rs_free(p);
 303                         return NULL;
 304                 }
 305                 if (parent != NULL) {
 306                         anchor->parent = parent;
 307                         if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
 308                             anchor)) != NULL) {
 309                                 printf("pf_find_or_create_ruleset: "
 310                                     "RB_INSERT2 '%s' '%s' collides with "
 311                                     "'%s' '%s'\n", anchor->path, anchor->name,
 312                                     dup->path, dup->name);
 313                                 RB_REMOVE(pf_anchor_global, &pf_anchors,
 314                                     anchor);
 315                                 rs_free(anchor);
 316                                 rs_free(p);
 317                                 return NULL;
 318                         }
 319                 }
 320                 pf_init_ruleset(&anchor->ruleset);
 321                 anchor->ruleset.anchor = anchor;
 322                 parent = anchor;
 323                 if (r != NULL) {
 324                         q = r + 1;
 325                 } else {
 326                         *q = 0;
 327                 }
 328 #if DUMMYNET
 329                 if (strncmp("com.apple.nlc", anchor->name,
 330                     sizeof("com.apple.nlc")) == 0) {
 331                         is_nlc_enabled_glb = TRUE;
 332                 }
 333 #endif
 334         }
 335         rs_free(p);
 336         return anchor ? &anchor->ruleset : 0;
 337 }
 338
 339 void
 340 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
 341 {
 342         struct pf_anchor        *parent;
 343         int                      i;
 344
 345         while (ruleset != NULL) {
 346                 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
 347                     !RB_EMPTY(&ruleset->anchor->children) ||
 348                     ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
 349                     ruleset->topen) {
 350                         return;
 351                 }
 352                 for (i = 0; i < PF_RULESET_MAX; ++i) {
 353                         if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
 354                             !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
 355                             ruleset->rules[i].inactive.open) {
 356                                 return;
 357                         }
 358                 }
 359                 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
 360 #if DUMMYNET
 361                 if (strncmp("com.apple.nlc", ruleset->anchor->name,
 362                     sizeof("com.apple.nlc")) == 0) {
 363                         struct dummynet_event dn_event;
 364                         bzero(&dn_event, sizeof(dn_event));
 365                         dn_event.dn_event_code = DUMMYNET_NLC_DISABLED;
 366                         dummynet_event_enqueue_nwk_wq_entry(&dn_event);
 367                         is_nlc_enabled_glb = FALSE;
 368                 }
 369 #endif
 370                 if ((parent = ruleset->anchor->parent) != NULL) {
 371                         RB_REMOVE(pf_anchor_node, &parent->children,
 372                             ruleset->anchor);
 373                 }
 374                 rs_free(ruleset->anchor);
 375                 if (parent == NULL) {
 376                         return;
 377                 }
 378                 ruleset = &parent->ruleset;
 379         }
 380 }
 381
 382 int
 383 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
 384     const char *name)
 385 {
 386         char                    *p, *path;
 387         struct pf_ruleset       *ruleset;
 388
 389         r->anchor = NULL;
 390         r->anchor_relative = 0;
 391         r->anchor_wildcard = 0;
 392         if (!name[0]) {
 393                 return 0;
 394         }
 395         path = (char *)rs_malloc(MAXPATHLEN);
 396         bzero(path, MAXPATHLEN);
 397         if (name[0] == '/') {
 398                 strlcpy(path, name + 1, MAXPATHLEN);
 399         } else {
 400                 /* relative path */
 401                 r->anchor_relative = 1;
 402                 if (s->anchor == NULL || !s->anchor->path[0]) {
 403                         path[0] = 0;
 404                 } else {
 405                         strlcpy(path, s->anchor->path, MAXPATHLEN);
 406                 }
 407                 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
 408                         if (!path[0]) {
 409                                 printf("pf_anchor_setup: .. beyond root\n");
 410                                 rs_free(path);
 411                                 return 1;
 412                         }
 413                         if ((p = strrchr(path, '/')) != NULL) {
 414                                 *p = 0;
 415                         } else {
 416                                 path[0] = 0;
 417                         }
 418                         r->anchor_relative++;
 419                         name += 3;
 420                 }
 421                 if (path[0]) {
 422                         strlcat(path, "/", MAXPATHLEN);
 423                 }
 424                 strlcat(path, name, MAXPATHLEN);
 425         }
 426         if ((p = strrchr(path, '/')) != NULL && strcmp(p, "/*") == 0) {
 427                 r->anchor_wildcard = 1;
 428                 *p = 0;
 429         }
 430         ruleset = pf_find_or_create_ruleset(path);
 431         rs_free(path);
 432         if (ruleset == NULL || ruleset->anchor == NULL) {
 433                 printf("pf_anchor_setup: ruleset\n");
 434                 return 1;
 435         }
 436         r->anchor = ruleset->anchor;
 437         r->anchor->refcnt++;
 438         return 0;
 439 }
 440
 441 int
 442 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
 443     struct pfioc_rule *pr)
 444 {
 445         pr->anchor_call[0] = 0;
 446         if (r->anchor == NULL) {
 447                 return 0;
 448         }
 449         if (!r->anchor_relative) {
 450                 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
 451                 strlcat(pr->anchor_call, r->anchor->path,
 452                     sizeof(pr->anchor_call));
 453         } else {
 454                 char    *a, *p;
 455                 int      i;
 456
 457                 a = (char *)rs_malloc(MAXPATHLEN);
 458                 bzero(a, MAXPATHLEN);
 459                 if (rs->anchor == NULL) {
 460                         a[0] = 0;
 461                 } else {
 462                         strlcpy(a, rs->anchor->path, MAXPATHLEN);
 463                 }
 464                 for (i = 1; i < r->anchor_relative; ++i) {
 465                         if ((p = strrchr(a, '/')) == NULL) {
 466                                 p = a;
 467                         }
 468                         *p = 0;
 469                         strlcat(pr->anchor_call, "../",
 470                             sizeof(pr->anchor_call));
 471                 }
 472                 if (strncmp(a, r->anchor->path, strlen(a))) {
 473                         printf("pf_anchor_copyout: '%s' '%s'\n", a,
 474                             r->anchor->path);
 475                         rs_free(a);
 476                         return 1;
 477                 }
 478                 if (strlen(r->anchor->path) > strlen(a)) {
 479                         strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
 480                             strlen(a) + 1 : 0), sizeof(pr->anchor_call));
 481                 }
 482                 rs_free(a);
 483         }
 484         if (r->anchor_wildcard) {
 485                 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
 486                     sizeof(pr->anchor_call));
 487         }
 488         return 0;
 489 }
 490
 491 void
 492 pf_anchor_remove(struct pf_rule *r)
 493 {
 494         if (r->anchor == NULL) {
 495                 return;
 496         }
 497         if (r->anchor->refcnt <= 0) {
 498                 printf("pf_anchor_remove: broken refcount\n");
 499                 r->anchor = NULL;
 500                 return;
 501         }
 502         if (!--r->anchor->refcnt) {
 503                 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
 504         }
 505         r->anchor = NULL;
 506 }