contrib/bind-9.2.4rc7/bin/named/sortlist.c

   1 /*
   2  * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2000, 2001  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: sortlist.c,v 1.5.2.1 2004/03/09 06:09:20 marka Exp $ */
  19
  20 #include <config.h>
  21
  22 #include <isc/mem.h>
  23 #include <isc/util.h>
  24
  25 #include <dns/acl.h>
  26 #include <dns/result.h>
  27
  28 #include <named/globals.h>
  29 #include <named/server.h>
  30 #include <named/sortlist.h>
  31
  32 ns_sortlisttype_t
  33 ns_sortlist_setup(dns_acl_t *acl, isc_netaddr_t *clientaddr, void **argp) {
  34         unsigned int i;
  35
  36         if (acl == NULL)
  37                 goto dont_sort;
  38
  39         for (i = 0; i < acl->length; i++) {
  40                 /*
  41                  * 'e' refers to the current 'top level statement'
  42                  * in the sortlist (see ARM).
  43                  */
  44                 dns_aclelement_t *e = &acl->elements[i];
  45                 dns_aclelement_t *matchelt = NULL;
  46                 dns_acl_t *inner;
  47
  48                 if (e->type != dns_aclelementtype_nestedacl)
  49                         goto dont_sort;
  50
  51                 inner = e->u.nestedacl;
  52
  53                 if (inner->length < 1 || inner->length > 2)
  54                         goto dont_sort;
  55
  56                 if (inner->elements[0].negative)
  57                         goto dont_sort;
  58
  59                 if (dns_aclelement_match(clientaddr, NULL,
  60                                          &inner->elements[0],
  61                                          &ns_g_server->aclenv,
  62                                          &matchelt)) {
  63                         if (inner->length == 2) {
  64                                 dns_aclelement_t *elt1 = &inner->elements[1];
  65                                 if (elt1->type == dns_aclelementtype_nestedacl)
  66                                         *argp = elt1->u.nestedacl;
  67                                 else if (elt1->type == dns_aclelementtype_localhost &&
  68                                          ns_g_server->aclenv.localhost != NULL)
  69                                         *argp = ns_g_server->aclenv.localhost;
  70                                 else if (elt1->type == dns_aclelementtype_localnets &&
  71                                          ns_g_server->aclenv.localnets != NULL)
  72                                         *argp = ns_g_server->aclenv.localnets;
  73                                 else
  74                                         goto dont_sort;
  75                                 return (NS_SORTLISTTYPE_2ELEMENT);
  76                         } else {
  77                                 INSIST(matchelt != NULL);
  78                                 *argp = matchelt;
  79                                 return (NS_SORTLISTTYPE_1ELEMENT);
  80                         }
  81                 }
  82         }
  83
  84         /* No match; don't sort. */
  85  dont_sort:
  86         *argp = NULL;
  87         return (NS_SORTLISTTYPE_NONE);
  88 }
  89
  90 int
  91 ns_sortlist_addrorder2(isc_netaddr_t *addr, void *arg) {
  92         dns_acl_t *sortacl = (dns_acl_t *) arg;
  93         int match;
  94
  95         (void)dns_acl_match(addr, NULL, sortacl,
  96                             &ns_g_server->aclenv,
  97                             &match, NULL);
  98         if (match > 0)
  99                 return (match);
 100         else if (match < 0)
 101                 return (INT_MAX - (-match));
 102         else
 103                 return (INT_MAX / 2);
 104 }
 105
 106 int
 107 ns_sortlist_addrorder1(isc_netaddr_t *addr, void *arg) {
 108         dns_aclelement_t *matchelt = (dns_aclelement_t *) arg;
 109         if (dns_aclelement_match(addr, NULL, matchelt,
 110                                  &ns_g_server->aclenv,
 111                                  NULL)) {
 112                 return (0);
 113         } else {
 114                 return (INT_MAX);
 115         }
 116 }
 117
 118 void
 119 ns_sortlist_byaddrsetup(dns_acl_t *sortlist_acl, isc_netaddr_t *client_addr,
 120                        dns_addressorderfunc_t *orderp,
 121                        void **argp)
 122 {
 123         ns_sortlisttype_t sortlisttype;
 124
 125         sortlisttype = ns_sortlist_setup(sortlist_acl, client_addr, argp);
 126
 127         switch (sortlisttype) {
 128         case NS_SORTLISTTYPE_1ELEMENT:
 129                 *orderp = ns_sortlist_addrorder1;
 130                 break;
 131         case NS_SORTLISTTYPE_2ELEMENT:
 132                 *orderp = ns_sortlist_addrorder2;
 133                 break;
 134         case NS_SORTLISTTYPE_NONE:
 135                 *orderp = NULL;
 136                 break;
 137         default:
 138                 UNEXPECTED_ERROR(__FILE__, __LINE__,
 139                                  "unexpected return from ns_sortlist_setup(): "
 140                                  "%d", sortlisttype);
 141                 break;
 142         }
 143 }
 144