contrib/bind-9.5.2/lib/dns/include/dns/acl.h

   1 /*
   2  * Copyright (C) 2004-2007, 2009  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2002  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and/or 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: acl.h,v 1.31.2.2 2009/01/19 23:47:03 tbox Exp $ */
  19
  20 #ifndef DNS_ACL_H
  21 #define DNS_ACL_H 1
  22
  23 /*****
  24  ***** Module Info
  25  *****/
  26
  27 /*! \file dns/acl.h
  28  * \brief
  29  * Address match list handling.
  30  */
  31
  32 /***
  33  *** Imports
  34  ***/
  35
  36 #include <isc/lang.h>
  37 #include <isc/magic.h>
  38 #include <isc/netaddr.h>
  39 #include <isc/refcount.h>
  40
  41 #include <dns/name.h>
  42 #include <dns/types.h>
  43 #include <dns/iptable.h>
  44
  45 /***
  46  *** Types
  47  ***/
  48
  49 typedef enum {
  50         dns_aclelementtype_ipprefix,
  51         dns_aclelementtype_keyname,
  52         dns_aclelementtype_nestedacl,
  53         dns_aclelementtype_localhost,
  54         dns_aclelementtype_localnets,
  55         dns_aclelementtype_any
  56 } dns_aclelemettype_t;
  57
  58 typedef struct dns_aclipprefix dns_aclipprefix_t;
  59
  60 struct dns_aclipprefix {
  61         isc_netaddr_t address; /* IP4/IP6 */
  62         unsigned int prefixlen;
  63 };
  64
  65 struct dns_aclelement {
  66         dns_aclelemettype_t     type;
  67         isc_boolean_t           negative;
  68         dns_name_t              keyname;
  69         dns_acl_t               *nestedacl;
  70         int                     node_num;
  71 };
  72
  73 struct dns_acl {
  74         unsigned int            magic;
  75         isc_mem_t               *mctx;
  76         isc_refcount_t          refcount;
  77         dns_iptable_t           *iptable;
  78 #define node_count              iptable->radix->num_added_node
  79         dns_aclelement_t        *elements;
  80         isc_boolean_t           has_negatives;
  81         unsigned int            alloc;          /*%< Elements allocated */
  82         unsigned int            length;         /*%< Elements initialized */
  83         char                    *name;          /*%< Temporary use only */
  84         ISC_LINK(dns_acl_t)     nextincache;    /*%< Ditto */
  85 };
  86
  87 struct dns_aclenv {
  88         dns_acl_t *localhost;
  89         dns_acl_t *localnets;
  90         isc_boolean_t match_mapped;
  91 };
  92
  93 #define DNS_ACL_MAGIC           ISC_MAGIC('D','a','c','l')
  94 #define DNS_ACL_VALID(a)        ISC_MAGIC_VALID(a, DNS_ACL_MAGIC)
  95
  96 /***
  97  *** Functions
  98  ***/
  99
 100 ISC_LANG_BEGINDECLS
 101
 102 isc_result_t
 103 dns_acl_create(isc_mem_t *mctx, int n, dns_acl_t **target);
 104 /*%<
 105  * Create a new ACL, including an IP table and an array with room
 106  * for 'n' ACL elements.  The elements are uninitialized and the
 107  * length is 0.
 108  */
 109
 110 isc_result_t
 111 dns_acl_any(isc_mem_t *mctx, dns_acl_t **target);
 112 /*%<
 113  * Create a new ACL that matches everything.
 114  */
 115
 116 isc_result_t
 117 dns_acl_none(isc_mem_t *mctx, dns_acl_t **target);
 118 /*%<
 119  * Create a new ACL that matches nothing.
 120  */
 121
 122 isc_boolean_t
 123 dns_acl_isany(dns_acl_t *acl);
 124 /*%<
 125  * Test whether ACL is set to "{ any; }"
 126  */
 127
 128 isc_boolean_t
 129 dns_acl_isnone(dns_acl_t *acl);
 130 /*%<
 131  * Test whether ACL is set to "{ none; }"
 132  */
 133
 134 isc_result_t
 135 dns_acl_merge(dns_acl_t *dest, dns_acl_t *source, isc_boolean_t pos);
 136 /*%<
 137  * Merge the contents of one ACL into another.  Call dns_iptable_merge()
 138  * for the IP tables, then concatenate the element arrays.
 139  *
 140  * If pos is set to false, then the nested ACL is to be negated.  This
 141  * means reverse the sense of each *positive* element or IP table node,
 142  * but leave negatives alone, so as to prevent a double-negative causing
 143  * an unexpected positive match in the parent ACL.
 144  */
 145
 146 void
 147 dns_acl_attach(dns_acl_t *source, dns_acl_t **target);
 148
 149 void
 150 dns_acl_detach(dns_acl_t **aclp);
 151
 152 isc_boolean_t
 153 dns_acl_isinsecure(const dns_acl_t *a);
 154 /*%<
 155  * Return #ISC_TRUE iff the acl 'a' is considered insecure, that is,
 156  * if it contains IP addresses other than those of the local host.
 157  * This is intended for applications such as printing warning
 158  * messages for suspect ACLs; it is not intended for making access
 159  * control decisions.  We make no guarantee that an ACL for which
 160  * this function returns #ISC_FALSE is safe.
 161  */
 162
 163 isc_result_t
 164 dns_aclenv_init(isc_mem_t *mctx, dns_aclenv_t *env);
 165 /*%<
 166  * Initialize ACL environment, setting up localhost and localnets ACLs
 167  */
 168
 169 void
 170 dns_aclenv_copy(dns_aclenv_t *t, dns_aclenv_t *s);
 171
 172 void
 173 dns_aclenv_destroy(dns_aclenv_t *env);
 174
 175 isc_result_t
 176 dns_acl_match(const isc_netaddr_t *reqaddr,
 177               const dns_name_t *reqsigner,
 178               const dns_acl_t *acl,
 179               const dns_aclenv_t *env,
 180               int *match,
 181               const dns_aclelement_t **matchelt);
 182 /*%<
 183  * General, low-level ACL matching.  This is expected to
 184  * be useful even for weird stuff like the topology and sortlist statements.
 185  *
 186  * Match the address 'reqaddr', and optionally the key name 'reqsigner',
 187  * against 'acl'.  'reqsigner' may be NULL.
 188  *
 189  * If there is a match, '*match' will be set to an integer whose absolute
 190  * value corresponds to the order in which the matching value was inserted
 191  * into the ACL.  For a positive match, this value will be positive; for a
 192  * negative match, it will be negative.
 193  *
 194  * If there is no match, *match will be set to zero.
 195  *
 196  * If there is a match in the element list (either positive or negative)
 197  * and 'matchelt' is non-NULL, *matchelt will be pointed to the matching
 198  * element.
 199  *
 200  * Returns:
 201  *\li   #ISC_R_SUCCESS          Always succeeds.
 202  */
 203
 204 isc_boolean_t
 205 dns_aclelement_match(const isc_netaddr_t *reqaddr,
 206                      const dns_name_t *reqsigner,
 207                      const dns_aclelement_t *e,
 208                      const dns_aclenv_t *env,
 209                      const dns_aclelement_t **matchelt);
 210 /*%<
 211  * Like dns_acl_match, but matches against the single ACL element 'e'
 212  * rather than a complete ACL, and returns ISC_TRUE iff it matched.
 213  *
 214  * To determine whether the match was positive or negative, the
 215  * caller should examine e->negative.  Since the element 'e' may be
 216  * a reference to a named ACL or a nested ACL, a matching element
 217  * returned through 'matchelt' is not necessarily 'e' itself.
 218  */
 219
 220 ISC_LANG_ENDDECLS
 221
 222 #endif /* DNS_ACL_H */