sys/contrib/pf/net/pf_ruleset.c

   1 /*      $OpenBSD: pf_ruleset.c,v 1.1 2006/10/27 13:56:51 mcbride 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 #ifdef __FreeBSD__
  39 #include <sys/cdefs.h>
  40 __FBSDID("$FreeBSD$");
  41 #endif
  42
  43 #include <sys/param.h>
  44 #include <sys/socket.h>
  45 #ifdef _KERNEL
  46 # include <sys/systm.h>
  47 #endif /* _KERNEL */
  48 #include <sys/mbuf.h>
  49
  50 #include <netinet/in.h>
  51 #include <netinet/in_systm.h>
  52 #include <netinet/ip.h>
  53 #include <netinet/tcp.h>
  54
  55 #include <net/if.h>
  56 #include <net/pfvar.h>
  57
  58 #ifdef INET6
  59 #include <netinet/ip6.h>
  60 #endif /* INET6 */
  61
  62
  63 #ifdef _KERNEL
  64 # define DPFPRINTF(format, x...)                \
  65         if (pf_status.debug >= PF_DEBUG_NOISY)  \
  66                 printf(format , ##x)
  67 #ifdef __FreeBSD__
  68 #define rs_malloc(x)            malloc(x, M_TEMP, M_NOWAIT)
  69 #else
  70 #define rs_malloc(x)            malloc(x, M_TEMP, M_WAITOK)
  71 #endif
  72 #define rs_free(x)              free(x, M_TEMP)
  73
  74 #else
  75 /* Userland equivalents so we can lend code to pfctl et al. */
  76
  77 # include <arpa/inet.h>
  78 # include <errno.h>
  79 # include <stdio.h>
  80 # include <stdlib.h>
  81 # include <string.h>
  82 # define rs_malloc(x)            malloc(x)
  83 # define rs_free(x)              free(x)
  84
  85 # ifdef PFDEBUG
  86 #  include <sys/stdarg.h>
  87 #  define DPFPRINTF(format, x...)       fprintf(stderr, format , ##x)
  88 # else
  89 #  define DPFPRINTF(format, x...)       ((void)0)
  90 # endif /* PFDEBUG */
  91 #endif /* _KERNEL */
  92
  93
  94 struct pf_anchor_global  pf_anchors;
  95 struct pf_anchor         pf_main_anchor;
  96
  97 #ifndef __FreeBSD__
  98 /* XXX: hum? */
  99 int                      pf_get_ruleset_number(u_int8_t);
 100 void                     pf_init_ruleset(struct pf_ruleset *);
 101 int                      pf_anchor_setup(struct pf_rule *,
 102                             const struct pf_ruleset *, const char *);
 103 int                      pf_anchor_copyout(const struct pf_ruleset *,
 104                             const struct pf_rule *, struct pfioc_rule *);
 105 void                     pf_anchor_remove(struct pf_rule *);
 106 #endif
 107
 108 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
 109
 110 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
 111 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
 112
 113 static __inline int
 114 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
 115 {
 116         int c = strcmp(a->path, b->path);
 117
 118         return (c ? (c < 0 ? -1 : 1) : 0);
 119 }
 120
 121 int
 122 pf_get_ruleset_number(u_int8_t action)
 123 {
 124         switch (action) {
 125         case PF_SCRUB:
 126         case PF_NOSCRUB:
 127                 return (PF_RULESET_SCRUB);
 128                 break;
 129         case PF_PASS:
 130         case PF_DROP:
 131                 return (PF_RULESET_FILTER);
 132                 break;
 133         case PF_NAT:
 134         case PF_NONAT:
 135                 return (PF_RULESET_NAT);
 136                 break;
 137         case PF_BINAT:
 138         case PF_NOBINAT:
 139                 return (PF_RULESET_BINAT);
 140                 break;
 141         case PF_RDR:
 142         case PF_NORDR:
 143                 return (PF_RULESET_RDR);
 144                 break;
 145         default:
 146                 return (PF_RULESET_MAX);
 147                 break;
 148         }
 149 }
 150
 151 void
 152 pf_init_ruleset(struct pf_ruleset *ruleset)
 153 {
 154         int     i;
 155
 156         memset(ruleset, 0, sizeof(struct pf_ruleset));
 157         for (i = 0; i < PF_RULESET_MAX; i++) {
 158                 TAILQ_INIT(&ruleset->rules[i].queues[0]);
 159                 TAILQ_INIT(&ruleset->rules[i].queues[1]);
 160                 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
 161                 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
 162         }
 163 }
 164
 165 struct pf_anchor *
 166 pf_find_anchor(const char *path)
 167 {
 168         struct pf_anchor        *key, *found;
 169
 170         key = (struct pf_anchor *)rs_malloc(sizeof(*key));
 171         memset(key, 0, sizeof(*key));
 172         strlcpy(key->path, path, sizeof(key->path));
 173         found = RB_FIND(pf_anchor_global, &pf_anchors, key);
 174         rs_free(key);
 175         return (found);
 176 }
 177
 178 struct pf_ruleset *
 179 pf_find_ruleset(const char *path)
 180 {
 181         struct pf_anchor        *anchor;
 182
 183         while (*path == '/')
 184                 path++;
 185         if (!*path)
 186                 return (&pf_main_ruleset);
 187         anchor = pf_find_anchor(path);
 188         if (anchor == NULL)
 189                 return (NULL);
 190         else
 191                 return (&anchor->ruleset);
 192 }
 193
 194 struct pf_ruleset *
 195 pf_find_or_create_ruleset(const char *path)
 196 {
 197         char                    *p, *q, *r;
 198         struct pf_ruleset       *ruleset;
 199 #ifdef __FreeBSD__
 200         struct pf_anchor        *anchor = NULL, *dup, *parent = NULL;
 201 #else
 202         struct pf_anchor        *anchor, *dup, *parent = NULL;
 203 #endif
 204
 205         if (path[0] == 0)
 206                 return (&pf_main_ruleset);
 207         while (*path == '/')
 208                 path++;
 209         ruleset = pf_find_ruleset(path);
 210         if (ruleset != NULL)
 211                 return (ruleset);
 212         p = (char *)rs_malloc(MAXPATHLEN);
 213         bzero(p, MAXPATHLEN);
 214         strlcpy(p, path, MAXPATHLEN);
 215         while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
 216                 *q = 0;
 217                 if ((ruleset = pf_find_ruleset(p)) != NULL) {
 218                         parent = ruleset->anchor;
 219                         break;
 220                 }
 221         }
 222         if (q == NULL)
 223                 q = p;
 224         else
 225                 q++;
 226         strlcpy(p, path, MAXPATHLEN);
 227         if (!*q) {
 228                 rs_free(p);
 229                 return (NULL);
 230         }
 231         while ((r = strchr(q, '/')) != NULL || *q) {
 232                 if (r != NULL)
 233                         *r = 0;
 234                 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
 235                     (parent != NULL && strlen(parent->path) >=
 236                     MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
 237                         rs_free(p);
 238                         return (NULL);
 239                 }
 240                 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
 241                 if (anchor == NULL) {
 242                         rs_free(p);
 243                         return (NULL);
 244                 }
 245                 memset(anchor, 0, sizeof(*anchor));
 246                 RB_INIT(&anchor->children);
 247                 strlcpy(anchor->name, q, sizeof(anchor->name));
 248                 if (parent != NULL) {
 249                         strlcpy(anchor->path, parent->path,
 250                             sizeof(anchor->path));
 251                         strlcat(anchor->path, "/", sizeof(anchor->path));
 252                 }
 253                 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
 254                 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
 255                     NULL) {
 256                         printf("pf_find_or_create_ruleset: RB_INSERT1 "
 257                             "'%s' '%s' collides with '%s' '%s'\n",
 258                             anchor->path, anchor->name, dup->path, dup->name);
 259                         rs_free(anchor);
 260                         rs_free(p);
 261                         return (NULL);
 262                 }
 263                 if (parent != NULL) {
 264                         anchor->parent = parent;
 265                         if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
 266                             anchor)) != NULL) {
 267                                 printf("pf_find_or_create_ruleset: "
 268                                     "RB_INSERT2 '%s' '%s' collides with "
 269                                     "'%s' '%s'\n", anchor->path, anchor->name,
 270                                     dup->path, dup->name);
 271                                 RB_REMOVE(pf_anchor_global, &pf_anchors,
 272                                     anchor);
 273                                 rs_free(anchor);
 274                                 rs_free(p);
 275                                 return (NULL);
 276                         }
 277                 }
 278                 pf_init_ruleset(&anchor->ruleset);
 279                 anchor->ruleset.anchor = anchor;
 280                 parent = anchor;
 281                 if (r != NULL)
 282                         q = r + 1;
 283                 else
 284                         *q = 0;
 285         }
 286         rs_free(p);
 287         return (&anchor->ruleset);
 288 }
 289
 290 void
 291 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
 292 {
 293         struct pf_anchor        *parent;
 294         int                      i;
 295
 296         while (ruleset != NULL) {
 297                 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
 298                     !RB_EMPTY(&ruleset->anchor->children) ||
 299                     ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
 300                     ruleset->topen)
 301                         return;
 302                 for (i = 0; i < PF_RULESET_MAX; ++i)
 303                         if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
 304                             !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
 305                             ruleset->rules[i].inactive.open)
 306                                 return;
 307                 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
 308                 if ((parent = ruleset->anchor->parent) != NULL)
 309                         RB_REMOVE(pf_anchor_node, &parent->children,
 310                             ruleset->anchor);
 311                 rs_free(ruleset->anchor);
 312                 if (parent == NULL)
 313                         return;
 314                 ruleset = &parent->ruleset;
 315         }
 316 }
 317
 318 int
 319 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
 320     const char *name)
 321 {
 322         char                    *p, *path;
 323         struct pf_ruleset       *ruleset;
 324
 325         r->anchor = NULL;
 326         r->anchor_relative = 0;
 327         r->anchor_wildcard = 0;
 328         if (!name[0])
 329                 return (0);
 330         path = (char *)rs_malloc(MAXPATHLEN);
 331         bzero(path, MAXPATHLEN);
 332         if (name[0] == '/')
 333                 strlcpy(path, name + 1, MAXPATHLEN);
 334         else {
 335                 /* relative path */
 336                 r->anchor_relative = 1;
 337                 if (s->anchor == NULL || !s->anchor->path[0])
 338                         path[0] = 0;
 339                 else
 340                         strlcpy(path, s->anchor->path, MAXPATHLEN);
 341                 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
 342                         if (!path[0]) {
 343                                 printf("pf_anchor_setup: .. beyond root\n");
 344                                 rs_free(path);
 345                                 return (1);
 346                         }
 347                         if ((p = strrchr(path, '/')) != NULL)
 348                                 *p = 0;
 349                         else
 350                                 path[0] = 0;
 351                         r->anchor_relative++;
 352                         name += 3;
 353                 }
 354                 if (path[0])
 355                         strlcat(path, "/", MAXPATHLEN);
 356                 strlcat(path, name, MAXPATHLEN);
 357         }
 358         if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
 359                 r->anchor_wildcard = 1;
 360                 *p = 0;
 361         }
 362         ruleset = pf_find_or_create_ruleset(path);
 363         rs_free(path);
 364         if (ruleset == NULL || ruleset->anchor == NULL) {
 365                 printf("pf_anchor_setup: ruleset\n");
 366                 return (1);
 367         }
 368         r->anchor = ruleset->anchor;
 369         r->anchor->refcnt++;
 370         return (0);
 371 }
 372
 373 int
 374 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
 375     struct pfioc_rule *pr)
 376 {
 377         pr->anchor_call[0] = 0;
 378         if (r->anchor == NULL)
 379                 return (0);
 380         if (!r->anchor_relative) {
 381                 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
 382                 strlcat(pr->anchor_call, r->anchor->path,
 383                     sizeof(pr->anchor_call));
 384         } else {
 385                 char    *a, *p;
 386                 int      i;
 387
 388                 a = (char *)rs_malloc(MAXPATHLEN);
 389                 bzero(a, MAXPATHLEN);
 390                 if (rs->anchor == NULL)
 391                         a[0] = 0;
 392                 else
 393                         strlcpy(a, rs->anchor->path, MAXPATHLEN);
 394                 for (i = 1; i < r->anchor_relative; ++i) {
 395                         if ((p = strrchr(a, '/')) == NULL)
 396                                 p = a;
 397                         *p = 0;
 398                         strlcat(pr->anchor_call, "../",
 399                             sizeof(pr->anchor_call));
 400                 }
 401                 if (strncmp(a, r->anchor->path, strlen(a))) {
 402                         printf("pf_anchor_copyout: '%s' '%s'\n", a,
 403                             r->anchor->path);
 404                         rs_free(a);
 405                         return (1);
 406                 }
 407                 if (strlen(r->anchor->path) > strlen(a))
 408                         strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
 409                             strlen(a) + 1 : 0), sizeof(pr->anchor_call));
 410                 rs_free(a);
 411         }
 412         if (r->anchor_wildcard)
 413                 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
 414                     sizeof(pr->anchor_call));
 415         return (0);
 416 }
 417
 418 void
 419 pf_anchor_remove(struct pf_rule *r)
 420 {
 421         if (r->anchor == NULL)
 422                 return;
 423         if (r->anchor->refcnt <= 0) {
 424                 printf("pf_anchor_remove: broken refcount\n");
 425                 r->anchor = NULL;
 426                 return;
 427         }
 428         if (!--r->anchor->refcnt)
 429                 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
 430         r->anchor = NULL;
 431 }