contrib/bind-9.3/lib/dns/include/dns/validator.h

   1 /*
   2  * Copyright (C) 2004-2006  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2000-2003  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: validator.h,v 1.18.12.11.6.1 2007/01/11 04:51:39 marka Exp $ */
  19
  20 #ifndef DNS_VALIDATOR_H
  21 #define DNS_VALIDATOR_H 1
  22
  23 /*****
  24  ***** Module Info
  25  *****/
  26
  27 /*! \file
  28  *
  29  * \brief
  30  * DNS Validator
  31  * This is the BIND 9 validator, the module responsible for validating the
  32  * rdatasets and negative responses (messages).  It makes use of zones in
  33  * the view and may fetch RRset to complete trust chains.  It implements
  34  * DNSSEC as specified in RFC 4033, 4034 and 4035.
  35  *
  36  * It can also optionally implement ISC's DNSSEC look-aside validation.
  37  *
  38  * Correct operation is critical to preventing spoofed answers from secure
  39  * zones being accepted.
  40  *
  41  * MP:
  42  *\li   The module ensures appropriate synchronization of data structures it
  43  *      creates and manipulates.
  44  *
  45  * Reliability:
  46  *\li   No anticipated impact.
  47  *
  48  * Resources:
  49  *\li   TBS
  50  *
  51  * Security:
  52  *\li   No anticipated impact.
  53  *
  54  * Standards:
  55  *\li   RFCs:   1034, 1035, 2181, 4033, 4034, 4035.
  56  */
  57
  58 #include <isc/lang.h>
  59 #include <isc/event.h>
  60 #include <isc/mutex.h>
  61
  62 #include <dns/fixedname.h>
  63 #include <dns/types.h>
  64 #include <dns/rdataset.h>
  65 #include <dns/rdatastruct.h> /* for dns_rdata_rrsig_t */
  66
  67 #include <dst/dst.h>
  68
  69 /*%
  70  * A dns_validatorevent_t is sent when a 'validation' completes.
  71  * \brief
  72  * 'name', 'rdataset', 'sigrdataset', and 'message' are the values that were
  73  * supplied when dns_validator_create() was called.  They are returned to the
  74  * caller so that they may be freed.
  75  *
  76  * If the RESULT is ISC_R_SUCCESS and the answer is secure then
  77  * proofs[] will contain the the names of the NSEC records that hold the
  78  * various proofs.  Note the same name may appear multiple times.
  79  */
  80 typedef struct dns_validatorevent {
  81         ISC_EVENT_COMMON(struct dns_validatorevent);
  82         dns_validator_t *               validator;
  83         isc_result_t                    result;
  84         dns_name_t *                    name;
  85         dns_rdatatype_t                 type;
  86         dns_rdataset_t *                rdataset;
  87         dns_rdataset_t *                sigrdataset;
  88         dns_message_t *                 message;
  89         dns_name_t *                    proofs[3];
  90 } dns_validatorevent_t;
  91
  92 #define DNS_VALIDATOR_NOQNAMEPROOF 0
  93 #define DNS_VALIDATOR_NODATAPROOF 1
  94 #define DNS_VALIDATOR_NOWILDCARDPROOF 2
  95
  96 /*%
  97  * A validator object represents a validation in progress.
  98  * \brief
  99  * Clients are strongly discouraged from using this type directly, with
 100  * the exception of the 'link' field, which may be used directly for
 101  * whatever purpose the client desires.
 102  */
 103 struct dns_validator {
 104         /* Unlocked. */
 105         unsigned int                    magic;
 106         isc_mutex_t                     lock;
 107         dns_view_t *                    view;
 108         /* Locked by lock. */
 109         unsigned int                    options;
 110         unsigned int                    attributes;
 111         dns_validatorevent_t *          event;
 112         dns_fetch_t *                   fetch;
 113         dns_validator_t *               subvalidator;
 114         dns_validator_t *               parent;
 115         dns_keytable_t *                keytable;
 116         dns_keynode_t *                 keynode;
 117         dst_key_t *                     key;
 118         dns_rdata_rrsig_t *             siginfo;
 119         isc_task_t *                    task;
 120         isc_taskaction_t                action;
 121         void *                          arg;
 122         unsigned int                    labels;
 123         dns_rdataset_t *                currentset;
 124         isc_boolean_t                   seensig;
 125         dns_rdataset_t *                keyset;
 126         dns_rdataset_t *                dsset;
 127         dns_rdataset_t *                soaset;
 128         dns_rdataset_t *                nsecset;
 129         dns_name_t *                    soaname;
 130         dns_rdataset_t                  frdataset;
 131         dns_rdataset_t                  fsigrdataset;
 132         dns_fixedname_t                 fname;
 133         dns_fixedname_t                 wild;
 134         ISC_LINK(dns_validator_t)       link;
 135         dns_rdataset_t                  dlv;
 136         dns_fixedname_t                 dlvsep;
 137         isc_boolean_t                   havedlvsep;
 138         isc_boolean_t                   mustbesecure;
 139         unsigned int                    dlvlabels;
 140         unsigned int                    depth;
 141 };
 142
 143 /*%
 144  * dns_validator_create() options.
 145  */
 146 #define DNS_VALIDATOR_DLV 1U
 147 #define DNS_VALIDATOR_DEFER 2U
 148
 149 ISC_LANG_BEGINDECLS
 150
 151 isc_result_t
 152 dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
 153                      dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
 154                      dns_message_t *message, unsigned int options,
 155                      isc_task_t *task, isc_taskaction_t action, void *arg,
 156                      dns_validator_t **validatorp);
 157 /*%<
 158  * Start a DNSSEC validation.
 159  *
 160  * This validates a response to the question given by
 161  * 'name' and 'type'.
 162  *
 163  * To validate a positive response, the response data is
 164  * given by 'rdataset' and 'sigrdataset'.  If 'sigrdataset'
 165  * is NULL, the data is presumed insecure and an attempt
 166  * is made to prove its insecurity by finding the appropriate
 167  * null key.
 168  *
 169  * The complete response message may be given in 'message',
 170  * to make available any authority section NSECs that may be
 171  * needed for validation of a response resulting from a
 172  * wildcard expansion (though no such wildcard validation
 173  * is implemented yet).  If the complete response message
 174  * is not available, 'message' is NULL.
 175  *
 176  * To validate a negative response, the complete negative response
 177  * message is given in 'message'.  The 'rdataset', and
 178  * 'sigrdataset' arguments must be NULL, but the 'name' and 'type'
 179  * arguments must be provided.
 180  *
 181  * The validation is performed in the context of 'view'.
 182  *
 183  * When the validation finishes, a dns_validatorevent_t with
 184  * the given 'action' and 'arg' are sent to 'task'.
 185  * Its 'result' field will be ISC_R_SUCCESS iff the
 186  * response was successfully proven to be either secure or
 187  * part of a known insecure domain.
 188  *
 189  * options:
 190  * If DNS_VALIDATOR_DLV is set the caller knows there is not a
 191  * trusted key and the validator should immediately attempt to validate
 192  * the answer by looking for a appopriate DLV RRset.
 193  */
 194
 195 void
 196 dns_validator_send(dns_validator_t *validator);
 197 /*%<
 198  * Send a deferred validation request
 199  *
 200  * Requires:
 201  *      'validator' to points to a valid DNSSEC validator.
 202  */
 203
 204 void
 205 dns_validator_cancel(dns_validator_t *validator);
 206 /*%<
 207  * Cancel a DNSSEC validation in progress.
 208  *
 209  * Requires:
 210  *\li   'validator' points to a valid DNSSEC validator, which
 211  *      may or may not already have completed.
 212  *
 213  * Ensures:
 214  *\li   It the validator has not already sent its completion
 215  *      event, it will send it with result code ISC_R_CANCELED.
 216  */
 217
 218 void
 219 dns_validator_destroy(dns_validator_t **validatorp);
 220 /*%<
 221  * Destroy a DNSSEC validator.
 222  *
 223  * Requires:
 224  *\li   '*validatorp' points to a valid DNSSEC validator.
 225  * \li  The validator must have completed and sent its completion
 226  *      event.
 227  *
 228  * Ensures:
 229  *\li   All resources used by the validator are freed.
 230  */
 231
 232 ISC_LANG_ENDDECLS
 233
 234 #endif /* DNS_VALIDATOR_H */