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 __FBSDID("$FreeBSD$"); 41 42 #include <sys/param.h> 43 #include <sys/socket.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 #include <arpa/inet.h> 60 #include <errno.h> 61 #include <stdio.h> 62 #include <stdlib.h> 63 #include <string.h> 64 #define rs_malloc(x) calloc(1, x) 65 #define rs_free(x) free(x) 66 67 #include "pfctl.h" 68 69 #ifdef PFDEBUG 70 #include <sys/stdarg.h> 71 #define DPFPRINTF(format, x...) fprintf(stderr, format , ##x) 72 #else 73 #define DPFPRINTF(format, x...) ((void)0) 74 #endif /* PFDEBUG */ 75 76 struct pfctl_anchor_global pf_anchors; 77 struct pfctl_anchor pf_main_anchor; 78 #undef V_pf_anchors 79 #define V_pf_anchors pf_anchors 80 #undef pf_main_ruleset 81 #define pf_main_ruleset pf_main_anchor.ruleset 82 83 static __inline int pf_anchor_compare(struct pfctl_anchor *, 84 struct pfctl_anchor *); 85 static struct pfctl_anchor *pf_find_anchor(const char *); 86 87 RB_GENERATE(pfctl_anchor_global, pfctl_anchor, entry_global, 88 pf_anchor_compare); 89 RB_GENERATE(pfctl_anchor_node, pfctl_anchor, entry_node, pf_anchor_compare); 90 91 static __inline int 92 pf_anchor_compare(struct pfctl_anchor *a, struct pfctl_anchor *b) 93 { 94 int c = strcmp(a->path, b->path); 95 96 return (c ? (c < 0 ? -1 : 1) : 0); 97 } 98 99 int 100 pf_get_ruleset_number(u_int8_t action) 101 { 102 switch (action) { 103 case PF_SCRUB: 104 case PF_NOSCRUB: 105 return (PF_RULESET_SCRUB); 106 break; 107 case PF_PASS: 108 case PF_DROP: 109 return (PF_RULESET_FILTER); 110 break; 111 case PF_NAT: 112 case PF_NONAT: 113 return (PF_RULESET_NAT); 114 break; 115 case PF_BINAT: 116 case PF_NOBINAT: 117 return (PF_RULESET_BINAT); 118 break; 119 case PF_RDR: 120 case PF_NORDR: 121 return (PF_RULESET_RDR); 122 break; 123 default: 124 return (PF_RULESET_MAX); 125 break; 126 } 127 } 128 129 void 130 pf_init_ruleset(struct pfctl_ruleset *ruleset) 131 { 132 int i; 133 134 memset(ruleset, 0, sizeof(struct pfctl_ruleset)); 135 for (i = 0; i < PF_RULESET_MAX; i++) { 136 TAILQ_INIT(&ruleset->rules[i].queues[0]); 137 TAILQ_INIT(&ruleset->rules[i].queues[1]); 138 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0]; 139 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1]; 140 } 141 } 142 143 static struct pfctl_anchor * 144 pf_find_anchor(const char *path) 145 { 146 struct pfctl_anchor *key, *found; 147 148 key = (struct pfctl_anchor *)rs_malloc(sizeof(*key)); 149 if (key == NULL) 150 return (NULL); 151 strlcpy(key->path, path, sizeof(key->path)); 152 found = RB_FIND(pfctl_anchor_global, &V_pf_anchors, key); 153 rs_free(key); 154 return (found); 155 } 156 157 struct pfctl_ruleset * 158 pf_find_ruleset(const char *path) 159 { 160 struct pfctl_anchor *anchor; 161 162 while (*path == '/') 163 path++; 164 if (!*path) 165 return (&pf_main_ruleset); 166 anchor = pf_find_anchor(path); 167 if (anchor == NULL) 168 return (NULL); 169 else 170 return (&anchor->ruleset); 171 } 172 173 struct pfctl_ruleset * 174 pf_find_or_create_ruleset(const char *path) 175 { 176 char *p, *q, *r; 177 struct pfctl_ruleset *ruleset; 178 struct pfctl_anchor *anchor = NULL, *dup, *parent = NULL; 179 180 if (path[0] == 0) 181 return (&pf_main_ruleset); 182 while (*path == '/') 183 path++; 184 ruleset = pf_find_ruleset(path); 185 if (ruleset != NULL) 186 return (ruleset); 187 p = (char *)rs_malloc(MAXPATHLEN); 188 if (p == NULL) 189 return (NULL); 190 strlcpy(p, path, MAXPATHLEN); 191 while (parent == NULL && (q = strrchr(p, '/')) != NULL) { 192 *q = 0; 193 if ((ruleset = pf_find_ruleset(p)) != NULL) { 194 parent = ruleset->anchor; 195 break; 196 } 197 } 198 if (q == NULL) 199 q = p; 200 else 201 q++; 202 strlcpy(p, path, MAXPATHLEN); 203 if (!*q) { 204 rs_free(p); 205 return (NULL); 206 } 207 while ((r = strchr(q, '/')) != NULL || *q) { 208 if (r != NULL) 209 *r = 0; 210 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE || 211 (parent != NULL && strlen(parent->path) >= 212 MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) { 213 rs_free(p); 214 return (NULL); 215 } 216 anchor = (struct pfctl_anchor *)rs_malloc(sizeof(*anchor)); 217 if (anchor == NULL) { 218 rs_free(p); 219 return (NULL); 220 } 221 RB_INIT(&anchor->children); 222 strlcpy(anchor->name, q, sizeof(anchor->name)); 223 if (parent != NULL) { 224 strlcpy(anchor->path, parent->path, 225 sizeof(anchor->path)); 226 strlcat(anchor->path, "/", sizeof(anchor->path)); 227 } 228 strlcat(anchor->path, anchor->name, sizeof(anchor->path)); 229 if ((dup = RB_INSERT(pfctl_anchor_global, &V_pf_anchors, anchor)) != 230 NULL) { 231 printf("pf_find_or_create_ruleset: RB_INSERT1 " 232 "'%s' '%s' collides with '%s' '%s'\n", 233 anchor->path, anchor->name, dup->path, dup->name); 234 rs_free(anchor); 235 rs_free(p); 236 return (NULL); 237 } 238 if (parent != NULL) { 239 anchor->parent = parent; 240 if ((dup = RB_INSERT(pfctl_anchor_node, &parent->children, 241 anchor)) != NULL) { 242 printf("pf_find_or_create_ruleset: " 243 "RB_INSERT2 '%s' '%s' collides with " 244 "'%s' '%s'\n", anchor->path, anchor->name, 245 dup->path, dup->name); 246 RB_REMOVE(pfctl_anchor_global, &V_pf_anchors, 247 anchor); 248 rs_free(anchor); 249 rs_free(p); 250 return (NULL); 251 } 252 } 253 pf_init_ruleset(&anchor->ruleset); 254 anchor->ruleset.anchor = anchor; 255 parent = anchor; 256 if (r != NULL) 257 q = r + 1; 258 else 259 *q = 0; 260 } 261 rs_free(p); 262 return (&anchor->ruleset); 263 } 264 265 void 266 pf_remove_if_empty_ruleset(struct pfctl_ruleset *ruleset) 267 { 268 struct pfctl_anchor *parent; 269 int i; 270 271 while (ruleset != NULL) { 272 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL || 273 !RB_EMPTY(&ruleset->anchor->children) || 274 ruleset->anchor->refcnt > 0 || ruleset->tables > 0 || 275 ruleset->topen) 276 return; 277 for (i = 0; i < PF_RULESET_MAX; ++i) 278 if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) || 279 !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) || 280 ruleset->rules[i].inactive.open) 281 return; 282 RB_REMOVE(pfctl_anchor_global, &V_pf_anchors, ruleset->anchor); 283 if ((parent = ruleset->anchor->parent) != NULL) 284 RB_REMOVE(pfctl_anchor_node, &parent->children, 285 ruleset->anchor); 286 rs_free(ruleset->anchor); 287 if (parent == NULL) 288 return; 289 ruleset = &parent->ruleset; 290 } 291 } 292 int 293 pfctl_anchor_setup(struct pfctl_rule *r, const struct pfctl_ruleset *s, 294 const char *name) 295 { 296 char *p, *path; 297 struct pfctl_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("pfctl_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("pfctl_anchor_setup: ruleset\n"); 341 return (1); 342 } 343 r->anchor = ruleset->anchor; 344 r->anchor->refcnt++; 345 return (0); 346 } 347