root/net/pf_ruleset.c

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DEFINITIONS

This source file includes following definitions.
  1. pf_anchor_compare
  2. pf_get_ruleset_number
  3. pf_init_ruleset
  4. pf_find_anchor
  5. pf_find_ruleset
  6. pf_find_or_create_ruleset
  7. pf_remove_if_empty_ruleset
  8. pf_anchor_setup
  9. pf_anchor_copyout
  10. pf_anchor_remove

    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 #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)
   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)            malloc(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 int                      pf_get_ruleset_number(u_int8_t);
   89 void                     pf_init_ruleset(struct pf_ruleset *);
   90 int                      pf_anchor_setup(struct pf_rule *,
   91                             const struct pf_ruleset *, const char *);
   92 int                      pf_anchor_copyout(const struct pf_ruleset *,
   93                             const struct pf_rule *, struct pfioc_rule *);
   94 void                     pf_anchor_remove(struct pf_rule *);
   95 
   96 static __inline int pf_anchor_compare(struct pf_anchor *, struct pf_anchor *);
   97 
   98 RB_GENERATE(pf_anchor_global, pf_anchor, entry_global, pf_anchor_compare);
   99 RB_GENERATE(pf_anchor_node, pf_anchor, entry_node, pf_anchor_compare);
  100 
  101 static __inline int
  102 pf_anchor_compare(struct pf_anchor *a, struct pf_anchor *b)
  103 {
  104         int c = strcmp(a->path, b->path);
  105 
  106         return (c ? (c < 0 ? -1 : 1) : 0);
  107 }
  108 
  109 int
  110 pf_get_ruleset_number(u_int8_t action)
  111 {
  112         switch (action) {
  113         case PF_SCRUB:
  114         case PF_NOSCRUB:
  115                 return (PF_RULESET_SCRUB);
  116                 break;
  117         case PF_PASS:
  118         case PF_DROP:
  119                 return (PF_RULESET_FILTER);
  120                 break;
  121         case PF_NAT:
  122         case PF_NONAT:
  123                 return (PF_RULESET_NAT);
  124                 break;
  125         case PF_BINAT:
  126         case PF_NOBINAT:
  127                 return (PF_RULESET_BINAT);
  128                 break;
  129         case PF_RDR:
  130         case PF_NORDR:
  131                 return (PF_RULESET_RDR);
  132                 break;
  133         default:
  134                 return (PF_RULESET_MAX);
  135                 break;
  136         }
  137 }
  138 
  139 void
  140 pf_init_ruleset(struct pf_ruleset *ruleset)
  141 {
  142         int     i;
  143 
  144         memset(ruleset, 0, sizeof(struct pf_ruleset));
  145         for (i = 0; i < PF_RULESET_MAX; i++) {
  146                 TAILQ_INIT(&ruleset->rules[i].queues[0]);
  147                 TAILQ_INIT(&ruleset->rules[i].queues[1]);
  148                 ruleset->rules[i].active.ptr = &ruleset->rules[i].queues[0];
  149                 ruleset->rules[i].inactive.ptr = &ruleset->rules[i].queues[1];
  150         }
  151 }
  152 
  153 struct pf_anchor *
  154 pf_find_anchor(const char *path)
  155 {
  156         struct pf_anchor        *key, *found;
  157 
  158         key = (struct pf_anchor *)rs_malloc(sizeof(*key));
  159         memset(key, 0, sizeof(*key));
  160         strlcpy(key->path, path, sizeof(key->path));
  161         found = RB_FIND(pf_anchor_global, &pf_anchors, key);
  162         rs_free(key);
  163         return (found);
  164 }
  165 
  166 struct pf_ruleset *
  167 pf_find_ruleset(const char *path)
  168 {
  169         struct pf_anchor        *anchor;
  170 
  171         while (*path == '/')
  172                 path++;
  173         if (!*path)
  174                 return (&pf_main_ruleset);
  175         anchor = pf_find_anchor(path);
  176         if (anchor == NULL)
  177                 return (NULL);
  178         else
  179                 return (&anchor->ruleset);
  180 }
  181 
  182 struct pf_ruleset *
  183 pf_find_or_create_ruleset(const char *path)
  184 {
  185         char                    *p, *q, *r;
  186         struct pf_ruleset       *ruleset;
  187         struct pf_anchor        *anchor, *dup, *parent = NULL;
  188 
  189         if (path[0] == 0)
  190                 return (&pf_main_ruleset);
  191         while (*path == '/')
  192                 path++;
  193         ruleset = pf_find_ruleset(path);
  194         if (ruleset != NULL)
  195                 return (ruleset);
  196         p = (char *)rs_malloc(MAXPATHLEN);
  197         bzero(p, MAXPATHLEN);
  198         strlcpy(p, path, MAXPATHLEN);
  199         while (parent == NULL && (q = strrchr(p, '/')) != NULL) {
  200                 *q = 0;
  201                 if ((ruleset = pf_find_ruleset(p)) != NULL) {
  202                         parent = ruleset->anchor;
  203                         break;
  204                 }
  205         }
  206         if (q == NULL)
  207                 q = p;
  208         else
  209                 q++;
  210         strlcpy(p, path, MAXPATHLEN);
  211         if (!*q) {
  212                 rs_free(p);
  213                 return (NULL);
  214         }
  215         while ((r = strchr(q, '/')) != NULL || *q) {
  216                 if (r != NULL)
  217                         *r = 0;
  218                 if (!*q || strlen(q) >= PF_ANCHOR_NAME_SIZE ||
  219                     (parent != NULL && strlen(parent->path) >=
  220                     MAXPATHLEN - PF_ANCHOR_NAME_SIZE - 1)) {
  221                         rs_free(p);
  222                         return (NULL);
  223                 }
  224                 anchor = (struct pf_anchor *)rs_malloc(sizeof(*anchor));
  225                 if (anchor == NULL) {
  226                         rs_free(p);
  227                         return (NULL);
  228                 }
  229                 memset(anchor, 0, sizeof(*anchor));
  230                 RB_INIT(&anchor->children);
  231                 strlcpy(anchor->name, q, sizeof(anchor->name));
  232                 if (parent != NULL) {
  233                         strlcpy(anchor->path, parent->path,
  234                             sizeof(anchor->path));
  235                         strlcat(anchor->path, "/", sizeof(anchor->path));
  236                 }
  237                 strlcat(anchor->path, anchor->name, sizeof(anchor->path));
  238                 if ((dup = RB_INSERT(pf_anchor_global, &pf_anchors, anchor)) !=
  239                     NULL) {
  240                         printf("pf_find_or_create_ruleset: RB_INSERT1 "
  241                             "'%s' '%s' collides with '%s' '%s'\n",
  242                             anchor->path, anchor->name, dup->path, dup->name);
  243                         rs_free(anchor);
  244                         rs_free(p);
  245                         return (NULL);
  246                 }
  247                 if (parent != NULL) {
  248                         anchor->parent = parent;
  249                         if ((dup = RB_INSERT(pf_anchor_node, &parent->children,
  250                             anchor)) != NULL) {
  251                                 printf("pf_find_or_create_ruleset: "
  252                                     "RB_INSERT2 '%s' '%s' collides with "
  253                                     "'%s' '%s'\n", anchor->path, anchor->name,
  254                                     dup->path, dup->name);
  255                                 RB_REMOVE(pf_anchor_global, &pf_anchors,
  256                                     anchor);
  257                                 rs_free(anchor);
  258                                 rs_free(p);
  259                                 return (NULL);
  260                         }
  261                 }
  262                 pf_init_ruleset(&anchor->ruleset);
  263                 anchor->ruleset.anchor = anchor;
  264                 parent = anchor;
  265                 if (r != NULL)
  266                         q = r + 1;
  267                 else
  268                         *q = 0;
  269         }
  270         rs_free(p);
  271         return (&anchor->ruleset);
  272 }
  273 
  274 void
  275 pf_remove_if_empty_ruleset(struct pf_ruleset *ruleset)
  276 {
  277         struct pf_anchor        *parent;
  278         int                      i;
  279 
  280         while (ruleset != NULL) {
  281                 if (ruleset == &pf_main_ruleset || ruleset->anchor == NULL ||
  282                     !RB_EMPTY(&ruleset->anchor->children) ||
  283                     ruleset->anchor->refcnt > 0 || ruleset->tables > 0 ||
  284                     ruleset->topen)
  285                         return;
  286                 for (i = 0; i < PF_RULESET_MAX; ++i)
  287                         if (!TAILQ_EMPTY(ruleset->rules[i].active.ptr) ||
  288                             !TAILQ_EMPTY(ruleset->rules[i].inactive.ptr) ||
  289                             ruleset->rules[i].inactive.open)
  290                                 return;
  291                 RB_REMOVE(pf_anchor_global, &pf_anchors, ruleset->anchor);
  292                 if ((parent = ruleset->anchor->parent) != NULL)
  293                         RB_REMOVE(pf_anchor_node, &parent->children,
  294                             ruleset->anchor);
  295                 rs_free(ruleset->anchor);
  296                 if (parent == NULL)
  297                         return;
  298                 ruleset = &parent->ruleset;
  299         }
  300 }
  301 
  302 int
  303 pf_anchor_setup(struct pf_rule *r, const struct pf_ruleset *s,
  304     const char *name)
  305 {
  306         char                    *p, *path;
  307         struct pf_ruleset       *ruleset;
  308 
  309         r->anchor = NULL;
  310         r->anchor_relative = 0;
  311         r->anchor_wildcard = 0;
  312         if (!name[0])
  313                 return (0);
  314         path = (char *)rs_malloc(MAXPATHLEN);
  315         bzero(path, MAXPATHLEN);
  316         if (name[0] == '/')
  317                 strlcpy(path, name + 1, MAXPATHLEN);
  318         else {
  319                 /* relative path */
  320                 r->anchor_relative = 1;
  321                 if (s->anchor == NULL || !s->anchor->path[0])
  322                         path[0] = 0;
  323                 else
  324                         strlcpy(path, s->anchor->path, MAXPATHLEN);
  325                 while (name[0] == '.' && name[1] == '.' && name[2] == '/') {
  326                         if (!path[0]) {
  327                                 printf("pf_anchor_setup: .. beyond root\n");
  328                                 rs_free(path);
  329                                 return (1);
  330                         }
  331                         if ((p = strrchr(path, '/')) != NULL)
  332                                 *p = 0;
  333                         else
  334                                 path[0] = 0;
  335                         r->anchor_relative++;
  336                         name += 3;
  337                 }
  338                 if (path[0])
  339                         strlcat(path, "/", MAXPATHLEN);
  340                 strlcat(path, name, MAXPATHLEN);
  341         }
  342         if ((p = strrchr(path, '/')) != NULL && !strcmp(p, "/*")) {
  343                 r->anchor_wildcard = 1;
  344                 *p = 0;
  345         }
  346         ruleset = pf_find_or_create_ruleset(path);
  347         rs_free(path);
  348         if (ruleset == NULL || ruleset->anchor == NULL) {
  349                 printf("pf_anchor_setup: ruleset\n");
  350                 return (1);
  351         }
  352         r->anchor = ruleset->anchor;
  353         r->anchor->refcnt++;
  354         return (0);
  355 }
  356 
  357 int
  358 pf_anchor_copyout(const struct pf_ruleset *rs, const struct pf_rule *r,
  359     struct pfioc_rule *pr)
  360 {
  361         pr->anchor_call[0] = 0;
  362         if (r->anchor == NULL)
  363                 return (0);
  364         if (!r->anchor_relative) {
  365                 strlcpy(pr->anchor_call, "/", sizeof(pr->anchor_call));
  366                 strlcat(pr->anchor_call, r->anchor->path,
  367                     sizeof(pr->anchor_call));
  368         } else {
  369                 char    *a, *p;
  370                 int      i;
  371 
  372                 a = (char *)rs_malloc(MAXPATHLEN);
  373                 bzero(a, MAXPATHLEN);
  374                 if (rs->anchor == NULL)
  375                         a[0] = 0;
  376                 else
  377                         strlcpy(a, rs->anchor->path, MAXPATHLEN);
  378                 for (i = 1; i < r->anchor_relative; ++i) {
  379                         if ((p = strrchr(a, '/')) == NULL)
  380                                 p = a;
  381                         *p = 0;
  382                         strlcat(pr->anchor_call, "../",
  383                             sizeof(pr->anchor_call));
  384                 }
  385                 if (strncmp(a, r->anchor->path, strlen(a))) {
  386                         printf("pf_anchor_copyout: '%s' '%s'\n", a,
  387                             r->anchor->path);
  388                         rs_free(a);
  389                         return (1);
  390                 }
  391                 if (strlen(r->anchor->path) > strlen(a))
  392                         strlcat(pr->anchor_call, r->anchor->path + (a[0] ?
  393                             strlen(a) + 1 : 0), sizeof(pr->anchor_call));
  394                 rs_free(a);
  395         }
  396         if (r->anchor_wildcard)
  397                 strlcat(pr->anchor_call, pr->anchor_call[0] ? "/*" : "*",
  398                     sizeof(pr->anchor_call));
  399         return (0);
  400 }
  401 
  402 void
  403 pf_anchor_remove(struct pf_rule *r)
  404 {
  405         if (r->anchor == NULL)
  406                 return;
  407         if (r->anchor->refcnt <= 0) {
  408                 printf("pf_anchor_remove: broken refcount\n");
  409                 r->anchor = NULL;
  410                 return;
  411         }
  412         if (!--r->anchor->refcnt)
  413                 pf_remove_if_empty_ruleset(&r->anchor->ruleset);
  414         r->anchor = NULL;
  415 }

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