1 /* $OpenBSD: pf_ruleset.c,v 1.4 2009/04/06 12:05:55 henning 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 #include <sys/param.h> 39 #include <sys/socket.h> 40 #ifdef _KERNEL 41 # include <sys/systm.h> 42 #endif /* _KERNEL */ 43 #include <sys/mbuf.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 #include <netinet/tcp.h> 49 50 #include <net/if.h> 51 #include <net/pfvar.h> 52 53 #ifdef INET6 54 #include <netinet/ip6.h> 55 #endif /* INET6 */ 56 57 58 #ifdef _KERNEL 59 # define DPFPRINTF(format, x...) \ 60 if (pf_status.debug >= PF_DEBUG_NOISY) \ 61 printf(format , ##x) 62 #define rs_malloc(x) malloc(x, M_TEMP, M_WAITOK|M_CANFAIL|M_ZERO) 63 #define rs_free(x) free(x, M_TEMP) 64 65 #else 66 /* Userland equivalents so we can lend code to pfctl et al. */ 67 68 # include <arpa/inet.h> 69 # include <errno.h> 70 # include <stdio.h> 71 # include <stdlib.h> 72 # include <string.h> 73 # define rs_malloc(x) calloc(1, x) 74 # define rs_free(x) free(x) 75 76 # ifdef PFDEBUG 77 # include <sys/stdarg.h> 78 # define DPFPRINTF(format, x...) fprintf(stderr, format , ##x) 79 # else 80 # define DPFPRINTF(format, x...) ((void)0) 81 # endif /* PFDEBUG */ 82 #endif /* _KERNEL */ 83 84 85 struct pf_anchor_global pf_anchors; 86 struct pf_anchor pf_main_anchor; 87 88 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *); 89 90 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare); 91 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare); 92 93 static __inline int 94 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b) 95 { 96 int c = strcmp(a->path, b->path); 97 98 return (c ? (c < 0 ? -1 : 1) : 0); 99 } 100 101 int 102 pf_get_ruleset_number(u_int8_t action) 103 { 104 switch (action) { 105 case PF_PASS: 106 case PF_MATCH: 107 case PF_DROP: 108 return (PF_RULESET_FILTER); 109 break; 110 case PF_NAT: 111 case PF_NONAT: 112 return (PF_RULESET_NAT); 113 break; 114 case PF_BINAT: 115 case PF_NOBINAT: 116 return (PF_RULESET_BINAT); 117 break; 118 case PF_RDR: 119 case PF_NORDR: 120 return (PF_RULESET_RDR); 121 break; 122 default: 123 return (PF_RULESET_MAX); 124 break; 125 } 126 } 127 128 void 129 pf_init_ruleset(struct pf_ruleset *ruleset) 130 { 131 int i; 132 133 memset(ruleset, 0, sizeof(struct pf_ruleset)); 134 for (i = 0; i < PF_RULESET_MAX; i++) { 135 TAILQ_INIT(&ruleset->rules[i].queues[0]); 136 TAILQ_INIT(&ruleset->rules[i].queues[1]); 137 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0]; 138 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1]; 139 } 140 } 141 142 struct pf_anchor * 143 pf_find_anchor(const char *path) 144 { 145 struct pf_anchor *key, *found; 146 147 key = (struct pf_anchor *)rs_malloc(sizeof(*key)); 148 if (key == NULL) 149 return (NULL); 150 strlcpy(key->path, path, sizeof(key->path)); 151 found = RB_FIND(pf_anchor_global, &pf_anchors, key); 152 rs_free(key); 153 return (found); 154 } 155 156 struct pf_ruleset * 157 pf_find_ruleset(const char *path) 158 { 159 struct pf_anchor *anchor; 160 161 while (*path == '/') 162 path++; 163 if (!*path) 164 return (&pf_main_ruleset); 165 anchor = pf_find_anchor(path); 166 if (anchor == NULL) 167 return (NULL); 168 else 169 return (&anchor->ruleset); 170 } 171 172 struct pf_ruleset * 173 pf_find_or_create_ruleset(const char *path) 174 { 175 char *p, *q, *r; 176 struct pf_ruleset *ruleset; 177 struct pf_anchor *anchor, *dup, *parent = NULL; 178 179 if (path[0] == 0) 180 return (&pf_main_ruleset); 181 while (*path == '/') 182 path++; 183 ruleset = pf_find_ruleset(path); 184 if (ruleset != NULL) 185 return (ruleset); 186 p = (char *)rs_malloc(MAXPATHLEN); 187 if (p == NULL) 188 return (NULL); 189 strlcpy(p, path, MAXPATHLEN); 190 while (parent == NULL && (q = strrchr(p, '/')) != NULL) { 191 *q = 0; 192 if ((ruleset = pf_find_ruleset(p)) != NULL) { 193 parent = ruleset->anchor; 194 break; 195 } 196 } 197 if (q == NULL) 198 q = p; 199 else 200 q++; 201 strlcpy(p, path, MAXPATHLEN); 202 if (!*q) { 203 rs_free(p); 204 return (NULL); 205 } 206 while ((r = strchr(q, '/')) != NULL || *q) { 207 if (r != NULL) 208 *r = 0; 209 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE || 210 (parent != NULL && strlen(parent->path) >= 211 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) { 212 rs_free(p); 213 return (NULL); 214 } 215 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor)); 216 if (anchor == NULL) { 217 rs_free(p); 218 return (NULL); 219 } 220 RB_INIT(&anchor->children); 221 strlcpy(anchor->name, q, sizeof(anchor->name)); 222 if (parent != NULL) { 223 strlcpy(anchor->path, parent->path, 224 sizeof(anchor->path)); 225 strlcat(anchor->path, "/", sizeof(anchor->path)); 226 } 227 strlcat(anchor->path, anchor->name, sizeof(anchor->path)); 228 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) != 229 NULL) { 230 printf("pf_find_or_create_ruleset: RB_INSERT1 " 231 "'%s' '%s' collides with '%s' '%s'\n", 232 anchor->path, anchor->name, dup->path, dup->name); 233 rs_free(anchor); 234 rs_free(p); 235 return (NULL); 236 } 237 if (parent != NULL) { 238 anchor->parent = parent; 239 if ((dup = RB_INSERT(pf_anchor_node, &parent->children, 240 anchor)) != NULL) { 241 printf("pf_find_or_create_ruleset: " 242 "RB_INSERT2 '%s' '%s' collides with " 243 "'%s' '%s'\n", anchor->path, anchor->name, 244 dup->path, dup->name); 245 RB_REMOVE(pf_anchor_global, &pf_anchors, 246 anchor); 247 rs_free(anchor); 248 rs_free(p); 249 return (NULL); 250 } 251 } 252 pf_init_ruleset(&anchor->ruleset); 253 anchor->ruleset.anchor = anchor; 254 parent = anchor; 255 if (r != NULL) 256 q = r + 1; 257 else 258 *q = 0; 259 } 260 rs_free(p); 261 return (&anchor->ruleset); 262 } 263 264 void 265 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset) 266 { 267 struct pf_anchor *parent; 268 int i; 269 270 while (ruleset != NULL) { 271 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL || 272 !RB_EMPTY(&ruleset->anchor->children) || 273 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 || 274 ruleset->topen) 275 return; 276 for (i = 0; i < PF_RULESET_MAX; ++i) 277 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) || 278 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) || 279 ruleset->rules[i].inactive.open) 280 return; 281 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor); 282 if ((parent = ruleset->anchor->parent) != NULL) 283 RB_REMOVE(pf_anchor_node, &parent->children, 284 ruleset->anchor); 285 rs_free(ruleset->anchor); 286 if (parent == NULL) 287 return; 288 ruleset = &parent->ruleset; 289 } 290 } 291 292 int 293 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s, 294 const char *name) 295 { 296 char *p, *path; 297 struct pf_ruleset *ruleset; 298 299 r->anchor = NULL; 300 r->anchor_relative = 0; 301 r->anchor_wildcard = 0; 302 if (!name[0]) 303 return (0); 304 path = (char *)rs_malloc(MAXPATHLEN); 305 if (path == NULL) 306 return (1); 307 if (name[0] == '/') 308 strlcpy(path, name + 1, MAXPATHLEN); 309 else { 310 /* relative path */ 311 r->anchor_relative = 1; 312 if (s->anchor == NULL || !s->anchor->path[0]) 313 path[0] = 0; 314 else 315 strlcpy(path, s->anchor->path, MAXPATHLEN); 316 while (name[0] == '.' && name[1] == '.' && name[2] == '/') { 317 if (!path[0]) { 318 printf("pf_anchor_setup: .. beyond root\n"); 319 rs_free(path); 320 return (1); 321 } 322 if ((p = strrchr(path, '/')) != NULL) 323 *p = 0; 324 else 325 path[0] = 0; 326 r->anchor_relative++; 327 name += 3; 328 } 329 if (path[0]) 330 strlcat(path, "/", MAXPATHLEN); 331 strlcat(path, name, MAXPATHLEN); 332 } 333 if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) { 334 r->anchor_wildcard = 1; 335 *p = 0; 336 } 337 ruleset = pf_find_or_create_ruleset(path); 338 rs_free(path); 339 if (ruleset == NULL || ruleset->anchor == NULL) { 340 printf("pf_anchor_setup: ruleset\n"); 341 return (1); 342 } 343 r->anchor = ruleset->anchor; 344 r->anchor->refcnt++; 345 return (0); 346 } 347 348 int 349 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r, 350 struct pfioc_rule *pr) 351 { 352 pr->anchor_call[0] = 0; 353 if (r->anchor == NULL) 354 return (0); 355 if (!r->anchor_relative) { 356 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call)); 357 strlcat(pr->anchor_call, r->anchor->path, 358 sizeof(pr->anchor_call)); 359 } else { 360 char *a, *p; 361 int i; 362 363 a = (char *)rs_malloc(MAXPATHLEN); 364 if (a == NULL) 365 return (1); 366 if (rs->anchor == NULL) 367 a[0] = 0; 368 else 369 strlcpy(a, rs->anchor->path, MAXPATHLEN); 370 for (i = 1; i < r->anchor_relative; ++i) { 371 if ((p = strrchr(a, '/')) == NULL) 372 p = a; 373 *p = 0; 374 strlcat(pr->anchor_call, "../", 375 sizeof(pr->anchor_call)); 376 } 377 if (strncmp(a, r->anchor->path, strlen(a))) { 378 printf("pf_anchor_copyout: '%s' '%s'\n", a, 379 r->anchor->path); 380 rs_free(a); 381 return (1); 382 } 383 if (strlen(r->anchor->path) > strlen(a)) 384 strlcat(pr->anchor_call, r->anchor->path + (a[0] ? 385 strlen(a) + 1 : 0), sizeof(pr->anchor_call)); 386 rs_free(a); 387 } 388 if (r->anchor_wildcard) 389 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*", 390 sizeof(pr->anchor_call)); 391 return (0); 392 } 393 394 void 395 pf_anchor_remove(struct pf_rule *r) 396 { 397 if (r->anchor == NULL) 398 return; 399 if (r->anchor->refcnt <= 0) { 400 printf("pf_anchor_remove: broken refcount\n"); 401 r->anchor = NULL; 402 return; 403 } 404 if (!--r->anchor->refcnt) 405 pf_remove_if_empty_ruleset(&r->anchor->ruleset); 406 r->anchor = NULL; 407 } 408