validator.c revision ea8278253210df030a24f0c89342b43fe279a127
/*
* Copyright (C) 2004-2011 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000-2003 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: validator.c,v 1.203 2011/05/26 04:35:02 marka Exp $ */
#include <config.h>
#include <isc/base32.h>
#include <isc/mem.h>
#include <isc/print.h>
#include <isc/sha2.h>
#include <isc/string.h>
#include <isc/task.h>
#include <isc/util.h>
#include <dns/db.h>
#include <dns/dnssec.h>
#include <dns/ds.h>
#include <dns/events.h>
#include <dns/keytable.h>
#include <dns/keyvalues.h>
#include <dns/log.h>
#include <dns/message.h>
#include <dns/ncache.h>
#include <dns/nsec.h>
#include <dns/nsec3.h>
#include <dns/rdata.h>
#include <dns/rdataset.h>
#include <dns/rdatatype.h>
#include <dns/resolver.h>
#include <dns/result.h>
#include <dns/validator.h>
#include <dns/view.h>
/*! \file
* \brief
* Basic processing sequences.
*
* \li When called with rdataset and sigrdataset:
* validator_start -> validate -> proveunsecure -> startfinddlvsep ->
* dlv_validator_start -> validator_start -> validate -> proveunsecure
*
* validator_start -> validate -> nsecvalidate (secure wildcard answer)
*
* \li When called with rdataset, sigrdataset and with DNS_VALIDATOR_DLV:
* validator_start -> startfinddlvsep -> dlv_validator_start ->
* validator_start -> validate -> proveunsecure
*
* \li When called with rdataset:
* validator_start -> proveunsecure -> startfinddlvsep ->
* dlv_validator_start -> validator_start -> proveunsecure
*
* \li When called with rdataset and with DNS_VALIDATOR_DLV:
* validator_start -> startfinddlvsep -> dlv_validator_start ->
* validator_start -> proveunsecure
*
* \li When called without a rdataset:
* validator_start -> nsecvalidate -> proveunsecure -> startfinddlvsep ->
* dlv_validator_start -> validator_start -> nsecvalidate -> proveunsecure
*
* Note: there isn't a case for DNS_VALIDATOR_DLV here as we want nsecvalidate()
* to always validate the authority section even when it does not contain
* signatures.
*
* validator_start: determines what type of validation to do.
* validate: attempts to perform a positive validation.
* proveunsecure: attempts to prove the answer comes from a unsecure zone.
* nsecvalidate: attempts to prove a negative response.
* startfinddlvsep: starts the DLV record lookup.
* dlv_validator_start: resets state and restarts the lookup using the
* DLV RRset found by startfinddlvsep.
*/
#define VALIDATOR_MAGIC ISC_MAGIC('V', 'a', 'l', '?')
#define VALID_VALIDATOR(v) ISC_MAGIC_VALID(v, VALIDATOR_MAGIC)
#define VALATTR_SHUTDOWN 0x0001 /*%< Shutting down. */
#define VALATTR_CANCELED 0x0002 /*%< Canceled. */
#define VALATTR_TRIEDVERIFY 0x0004 /*%< We have found a key and
* have attempted a verify. */
#define VALATTR_INSECURITY 0x0010 /*%< Attempting proveunsecure. */
#define VALATTR_DLVTRIED 0x0020 /*%< Looked for a DLV record. */
/*!
* NSEC proofs to be looked for.
*/
#define VALATTR_NEEDNOQNAME 0x00000100
#define VALATTR_NEEDNOWILDCARD 0x00000200
#define VALATTR_NEEDNODATA 0x00000400
/*!
* NSEC proofs that have been found.
*/
#define VALATTR_FOUNDNOQNAME 0x00001000
#define VALATTR_FOUNDNOWILDCARD 0x00002000
#define VALATTR_FOUNDNODATA 0x00004000
#define VALATTR_FOUNDCLOSEST 0x00008000
/*
*
*/
#define VALATTR_FOUNDOPTOUT 0x00010000
#define VALATTR_FOUNDUNKNOWN 0x00020000
#define NEEDNODATA(val) ((val->attributes & VALATTR_NEEDNODATA) != 0)
#define NEEDNOQNAME(val) ((val->attributes & VALATTR_NEEDNOQNAME) != 0)
#define NEEDNOWILDCARD(val) ((val->attributes & VALATTR_NEEDNOWILDCARD) != 0)
#define DLVTRIED(val) ((val->attributes & VALATTR_DLVTRIED) != 0)
#define FOUNDNODATA(val) ((val->attributes & VALATTR_FOUNDNODATA) != 0)
#define FOUNDNOQNAME(val) ((val->attributes & VALATTR_FOUNDNOQNAME) != 0)
#define FOUNDNOWILDCARD(val) ((val->attributes & VALATTR_FOUNDNOWILDCARD) != 0)
#define FOUNDCLOSEST(val) ((val->attributes & VALATTR_FOUNDCLOSEST) != 0)
#define FOUNDOPTOUT(val) ((val->attributes & VALATTR_FOUNDOPTOUT) != 0)
#define SHUTDOWN(v) (((v)->attributes & VALATTR_SHUTDOWN) != 0)
#define CANCELED(v) (((v)->attributes & VALATTR_CANCELED) != 0)
static void
destroy(dns_validator_t *val);
static isc_result_t
get_dst_key(dns_validator_t *val, dns_rdata_rrsig_t *siginfo,
dns_rdataset_t *rdataset);
static isc_result_t
validate(dns_validator_t *val, isc_boolean_t resume);
static isc_result_t
validatezonekey(dns_validator_t *val);
static isc_result_t
nsecvalidate(dns_validator_t *val, isc_boolean_t resume);
static isc_result_t
proveunsecure(dns_validator_t *val, isc_boolean_t have_ds,
isc_boolean_t resume);
static void
validator_logv(dns_validator_t *val, isc_logcategory_t *category,
isc_logmodule_t *module, int level, const char *fmt, va_list ap)
ISC_FORMAT_PRINTF(5, 0);
static void
validator_log(dns_validator_t *val, int level, const char *fmt, ...)
ISC_FORMAT_PRINTF(3, 4);
static void
validator_logcreate(dns_validator_t *val,
dns_name_t *name, dns_rdatatype_t type,
const char *caller, const char *operation);
static isc_result_t
dlv_validatezonekey(dns_validator_t *val);
static void
dlv_validator_start(dns_validator_t *val);
static isc_result_t
finddlvsep(dns_validator_t *val, isc_boolean_t resume);
static isc_result_t
startfinddlvsep(dns_validator_t *val, dns_name_t *unsecure);
/*%
* Mark the RRsets as a answer.
*/
static inline void
markanswer(dns_validator_t *val, const char *where) {
validator_log(val, ISC_LOG_DEBUG(3), "marking as answer (%s)", where);
if (val->event->rdataset != NULL)
dns_rdataset_settrust(val->event->rdataset, dns_trust_answer);
if (val->event->sigrdataset != NULL)
dns_rdataset_settrust(val->event->sigrdataset,
dns_trust_answer);
}
static inline void
marksecure(dns_validatorevent_t *event) {
dns_rdataset_settrust(event->rdataset, dns_trust_secure);
if (event->sigrdataset != NULL)
dns_rdataset_settrust(event->sigrdataset, dns_trust_secure);
}
static void
validator_done(dns_validator_t *val, isc_result_t result) {
isc_task_t *task;
if (val->event == NULL)
return;
/*
* Caller must be holding the lock.
*/
val->event->result = result;
task = val->event->ev_sender;
val->event->ev_sender = val;
val->event->ev_type = DNS_EVENT_VALIDATORDONE;
val->event->ev_action = val->action;
val->event->ev_arg = val->arg;
isc_task_sendanddetach(&task, (isc_event_t **)&val->event);
}
static inline isc_boolean_t
exit_check(dns_validator_t *val) {
/*
* Caller must be holding the lock.
*/
if (!SHUTDOWN(val))
return (ISC_FALSE);
INSIST(val->event == NULL);
if (val->fetch != NULL || val->subvalidator != NULL)
return (ISC_FALSE);
return (ISC_TRUE);
}
/*
* Check that we have atleast one supported algorithm in the DLV RRset.
*/
static inline isc_boolean_t
dlv_algorithm_supported(dns_validator_t *val) {
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_rdata_dlv_t dlv;
isc_result_t result;
for (result = dns_rdataset_first(&val->dlv);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&val->dlv)) {
dns_rdata_reset(&rdata);
dns_rdataset_current(&val->dlv, &rdata);
result = dns_rdata_tostruct(&rdata, &dlv, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_resolver_algorithm_supported(val->view->resolver,
val->event->name,
dlv.algorithm))
continue;
#ifdef HAVE_OPENSSL_GOST
if (dlv.digest_type != DNS_DSDIGEST_SHA256 &&
dlv.digest_type != DNS_DSDIGEST_SHA1 &&
dlv.digest_type != DNS_DSDIGEST_GOST)
continue;
#else
if (dlv.digest_type != DNS_DSDIGEST_SHA256 &&
dlv.digest_type != DNS_DSDIGEST_SHA1)
continue;
#endif
return (ISC_TRUE);
}
return (ISC_FALSE);
}
/*%
* Look in the NSEC record returned from a DS query to see if there is
* a NS RRset at this name. If it is found we are at a delegation point.
*/
static isc_boolean_t
isdelegation(dns_name_t *name, dns_rdataset_t *rdataset,
isc_result_t dbresult)
{
dns_fixedname_t fixed;
dns_label_t hashlabel;
dns_name_t nsec3name;
dns_rdata_nsec3_t nsec3;
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_rdataset_t set;
int order;
int scope;
isc_boolean_t found;
isc_buffer_t buffer;
isc_result_t result;
unsigned char hash[NSEC3_MAX_HASH_LENGTH];
unsigned char owner[NSEC3_MAX_HASH_LENGTH];
unsigned int length;
REQUIRE(dbresult == DNS_R_NXRRSET || dbresult == DNS_R_NCACHENXRRSET);
dns_rdataset_init(&set);
if (dbresult == DNS_R_NXRRSET)
dns_rdataset_clone(rdataset, &set);
else {
result = dns_ncache_getrdataset(rdataset, name,
dns_rdatatype_nsec, &set);
if (result == ISC_R_NOTFOUND)
goto trynsec3;
if (result != ISC_R_SUCCESS)
return (ISC_FALSE);
}
INSIST(set.type == dns_rdatatype_nsec);
found = ISC_FALSE;
result = dns_rdataset_first(&set);
if (result == ISC_R_SUCCESS) {
dns_rdataset_current(&set, &rdata);
found = dns_nsec_typepresent(&rdata, dns_rdatatype_ns);
dns_rdata_reset(&rdata);
}
dns_rdataset_disassociate(&set);
return (found);
trynsec3:
/*
* Iterate over the ncache entry.
*/
found = ISC_FALSE;
dns_name_init(&nsec3name, NULL);
dns_fixedname_init(&fixed);
dns_name_downcase(name, dns_fixedname_name(&fixed), NULL);
name = dns_fixedname_name(&fixed);
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset))
{
dns_ncache_current(rdataset, &nsec3name, &set);
if (set.type != dns_rdatatype_nsec3) {
dns_rdataset_disassociate(&set);
continue;
}
dns_name_getlabel(&nsec3name, 0, &hashlabel);
isc_region_consume(&hashlabel, 1);
isc_buffer_init(&buffer, owner, sizeof(owner));
result = isc_base32hex_decoderegion(&hashlabel, &buffer);
if (result != ISC_R_SUCCESS) {
dns_rdataset_disassociate(&set);
continue;
}
for (result = dns_rdataset_first(&set);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&set))
{
dns_rdata_reset(&rdata);
dns_rdataset_current(&set, &rdata);
(void)dns_rdata_tostruct(&rdata, &nsec3, NULL);
if (nsec3.hash != 1)
continue;
length = isc_iterated_hash(hash, nsec3.hash,
nsec3.iterations, nsec3.salt,
nsec3.salt_length,
name->ndata, name->length);
if (length != isc_buffer_usedlength(&buffer))
continue;
order = memcmp(hash, owner, length);
if (order == 0) {
found = dns_nsec3_typepresent(&rdata,
dns_rdatatype_ns);
dns_rdataset_disassociate(&set);
return (found);
}
if ((nsec3.flags & DNS_NSEC3FLAG_OPTOUT) == 0)
continue;
/*
* Does this optout span cover the name?
*/
scope = memcmp(owner, nsec3.next, nsec3.next_length);
if ((scope < 0 && order > 0 &&
memcmp(hash, nsec3.next, length) < 0) ||
(scope >= 0 && (order > 0 ||
memcmp(hash, nsec3.next, length) < 0)))
{
dns_rdataset_disassociate(&set);
return (ISC_TRUE);
}
}
dns_rdataset_disassociate(&set);
}
return (found);
}
/*%
* We have been asked to look for a key.
* If found resume the validation process.
* If not found fail the validation process.
*/
static void
fetch_callback_validator(isc_task_t *task, isc_event_t *event) {
dns_fetchevent_t *devent;
dns_validator_t *val;
dns_rdataset_t *rdataset;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
isc_result_t saved_result;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_FETCHDONE);
devent = (dns_fetchevent_t *)event;
val = devent->ev_arg;
rdataset = &val->frdataset;
eresult = devent->result;
/* Free resources which are not of interest. */
if (devent->node != NULL)
dns_db_detachnode(devent->db, &devent->node);
if (devent->db != NULL)
dns_db_detach(&devent->db);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
isc_event_free(&event);
dns_resolver_destroyfetch(&val->fetch);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in fetch_callback_validator");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"keyset with trust %s",
dns_trust_totext(rdataset->trust));
/*
* Only extract the dst key if the keyset is secure.
*/
if (rdataset->trust >= dns_trust_secure) {
result = get_dst_key(val, val->siginfo, rdataset);
if (result == ISC_R_SUCCESS)
val->keyset = &val->frdataset;
}
result = validate(val, ISC_TRUE);
if (result == DNS_R_NOVALIDSIG &&
(val->attributes & VALATTR_TRIEDVERIFY) == 0)
{
saved_result = result;
validator_log(val, ISC_LOG_DEBUG(3),
"falling back to insecurity proof");
val->attributes |= VALATTR_INSECURITY;
result = proveunsecure(val, ISC_FALSE, ISC_FALSE);
if (result == DNS_R_NOTINSECURE)
result = saved_result;
}
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"fetch_callback_validator: got %s",
isc_result_totext(eresult));
if (eresult == ISC_R_CANCELED)
validator_done(val, eresult);
else
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* We were asked to look for a DS record as part of following a key chain
* upwards. If found resume the validation process. If not found fail the
* validation process.
*/
static void
dsfetched(isc_task_t *task, isc_event_t *event) {
dns_fetchevent_t *devent;
dns_validator_t *val;
dns_rdataset_t *rdataset;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_FETCHDONE);
devent = (dns_fetchevent_t *)event;
val = devent->ev_arg;
rdataset = &val->frdataset;
eresult = devent->result;
/* Free resources which are not of interest. */
if (devent->node != NULL)
dns_db_detachnode(devent->db, &devent->node);
if (devent->db != NULL)
dns_db_detach(&devent->db);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
isc_event_free(&event);
dns_resolver_destroyfetch(&val->fetch);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in dsfetched");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"dsset with trust %s",
dns_trust_totext(rdataset->trust));
val->dsset = &val->frdataset;
result = validatezonekey(val);
if (result != DNS_R_WAIT)
validator_done(val, result);
} else if (eresult == DNS_R_CNAME ||
eresult == DNS_R_NXRRSET ||
eresult == DNS_R_NCACHENXRRSET ||
eresult == DNS_R_SERVFAIL) /* RFC 1034 parent? */
{
validator_log(val, ISC_LOG_DEBUG(3),
"falling back to insecurity proof (%s)",
dns_result_totext(eresult));
val->attributes |= VALATTR_INSECURITY;
result = proveunsecure(val, ISC_FALSE, ISC_FALSE);
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"dsfetched: got %s",
isc_result_totext(eresult));
if (eresult == ISC_R_CANCELED)
validator_done(val, eresult);
else
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* We were asked to look for the DS record as part of proving that a
* name is unsecure.
*
* If the DS record doesn't exist and the query name corresponds to
* a delegation point we are transitioning from a secure zone to a
* unsecure zone.
*
* If the DS record exists it will be secure. We can continue looking
* for the break point in the chain of trust.
*/
static void
dsfetched2(isc_task_t *task, isc_event_t *event) {
dns_fetchevent_t *devent;
dns_validator_t *val;
dns_name_t *tname;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_FETCHDONE);
devent = (dns_fetchevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
/* Free resources which are not of interest. */
if (devent->node != NULL)
dns_db_detachnode(devent->db, &devent->node);
if (devent->db != NULL)
dns_db_detach(&devent->db);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
dns_resolver_destroyfetch(&val->fetch);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in dsfetched2: %s",
dns_result_totext(eresult));
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == DNS_R_CNAME ||
eresult == DNS_R_NXRRSET ||
eresult == DNS_R_NCACHENXRRSET)
{
/*
* There is no DS. If this is a delegation, we're done.
*/
tname = dns_fixedname_name(&devent->foundname);
if (eresult != DNS_R_CNAME &&
isdelegation(tname, &val->frdataset, eresult)) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, no DS"
" and this is a delegation");
validator_done(val, DNS_R_MUSTBESECURE);
} else if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "dsfetched2");
validator_done(val, ISC_R_SUCCESS);
} else {
result = startfinddlvsep(val, tname);
if (result != DNS_R_WAIT)
validator_done(val, result);
}
} else {
result = proveunsecure(val, ISC_FALSE, ISC_TRUE);
if (result != DNS_R_WAIT)
validator_done(val, result);
}
} else if (eresult == ISC_R_SUCCESS ||
eresult == DNS_R_NXDOMAIN ||
eresult == DNS_R_NCACHENXDOMAIN)
{
/*
* There is a DS which may or may not be a zone cut.
* In either case we are still in a secure zone resume
* validation.
*/
result = proveunsecure(val, ISC_TF(eresult == ISC_R_SUCCESS),
ISC_TRUE);
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
if (eresult == ISC_R_CANCELED)
validator_done(val, eresult);
else
validator_done(val, DNS_R_NOVALIDDS);
}
isc_event_free(&event);
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Callback from when a DNSKEY RRset has been validated.
*
* Resumes the stalled validation process.
*/
static void
keyvalidated(isc_task_t *task, isc_event_t *event) {
dns_validatorevent_t *devent;
dns_validator_t *val;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
isc_result_t saved_result;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_VALIDATORDONE);
devent = (dns_validatorevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
isc_event_free(&event);
dns_validator_destroy(&val->subvalidator);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in keyvalidated");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"keyset with trust %s",
dns_trust_totext(val->frdataset.trust));
/*
* Only extract the dst key if the keyset is secure.
*/
if (val->frdataset.trust >= dns_trust_secure)
(void) get_dst_key(val, val->siginfo, &val->frdataset);
result = validate(val, ISC_TRUE);
if (result == DNS_R_NOVALIDSIG &&
(val->attributes & VALATTR_TRIEDVERIFY) == 0)
{
saved_result = result;
validator_log(val, ISC_LOG_DEBUG(3),
"falling back to insecurity proof");
val->attributes |= VALATTR_INSECURITY;
result = proveunsecure(val, ISC_FALSE, ISC_FALSE);
if (result == DNS_R_NOTINSECURE)
result = saved_result;
}
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
if (eresult != DNS_R_BROKENCHAIN) {
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_expire(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_expire(&val->fsigrdataset);
}
validator_log(val, ISC_LOG_DEBUG(3),
"keyvalidated: got %s",
isc_result_totext(eresult));
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Callback when the DS record has been validated.
*
* Resumes validation of the zone key or the unsecure zone proof.
*/
static void
dsvalidated(isc_task_t *task, isc_event_t *event) {
dns_validatorevent_t *devent;
dns_validator_t *val;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_VALIDATORDONE);
devent = (dns_validatorevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
isc_event_free(&event);
dns_validator_destroy(&val->subvalidator);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in dsvalidated");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
isc_boolean_t have_dsset;
dns_name_t *name;
validator_log(val, ISC_LOG_DEBUG(3),
"%s with trust %s",
val->frdataset.type == dns_rdatatype_ds ?
"dsset" : "ds non-existance",
dns_trust_totext(val->frdataset.trust));
have_dsset = ISC_TF(val->frdataset.type == dns_rdatatype_ds);
name = dns_fixedname_name(&val->fname);
if ((val->attributes & VALATTR_INSECURITY) != 0 &&
val->frdataset.covers == dns_rdatatype_ds &&
val->frdataset.type == 0 &&
isdelegation(name, &val->frdataset, DNS_R_NCACHENXRRSET)) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, no DS "
"and this is a delegation");
result = DNS_R_MUSTBESECURE;
} else if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "dsvalidated");
result = ISC_R_SUCCESS;;
} else
result = startfinddlvsep(val, name);
} else if ((val->attributes & VALATTR_INSECURITY) != 0) {
result = proveunsecure(val, have_dsset, ISC_TRUE);
} else
result = validatezonekey(val);
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
if (eresult != DNS_R_BROKENCHAIN) {
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_expire(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_expire(&val->fsigrdataset);
}
validator_log(val, ISC_LOG_DEBUG(3),
"dsvalidated: got %s",
isc_result_totext(eresult));
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Callback when the CNAME record has been validated.
*
* Resumes validation of the unsecure zone proof.
*/
static void
cnamevalidated(isc_task_t *task, isc_event_t *event) {
dns_validatorevent_t *devent;
dns_validator_t *val;
isc_boolean_t want_destroy;
isc_result_t result;
isc_result_t eresult;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_VALIDATORDONE);
devent = (dns_validatorevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
isc_event_free(&event);
dns_validator_destroy(&val->subvalidator);
INSIST(val->event != NULL);
INSIST((val->attributes & VALATTR_INSECURITY) != 0);
validator_log(val, ISC_LOG_DEBUG(3), "in cnamevalidated");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3), "cname with trust %s",
dns_trust_totext(val->frdataset.trust));
result = proveunsecure(val, ISC_FALSE, ISC_TRUE);
if (result != DNS_R_WAIT)
validator_done(val, result);
} else {
if (eresult != DNS_R_BROKENCHAIN) {
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_expire(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_expire(&val->fsigrdataset);
}
validator_log(val, ISC_LOG_DEBUG(3),
"cnamevalidated: got %s",
isc_result_totext(eresult));
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Return ISC_R_SUCCESS if we can determine that the name doesn't exist
* or we can determine whether there is data or not at the name.
* If the name does not exist return the wildcard name.
*
* Return ISC_R_IGNORE when the NSEC is not the appropriate one.
*/
static isc_result_t
nsecnoexistnodata(dns_validator_t *val, dns_name_t* name, dns_name_t *nsecname,
dns_rdataset_t *nsecset, isc_boolean_t *exists,
isc_boolean_t *data, dns_name_t *wild)
{
int order;
dns_rdata_t rdata = DNS_RDATA_INIT;
isc_result_t result;
dns_namereln_t relation;
unsigned int olabels, nlabels, labels;
dns_rdata_nsec_t nsec;
isc_boolean_t atparent;
isc_boolean_t ns;
isc_boolean_t soa;
REQUIRE(exists != NULL);
REQUIRE(data != NULL);
REQUIRE(nsecset != NULL &&
nsecset->type == dns_rdatatype_nsec);
result = dns_rdataset_first(nsecset);
if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"failure processing NSEC set");
return (result);
}
dns_rdataset_current(nsecset, &rdata);
validator_log(val, ISC_LOG_DEBUG(3), "looking for relevant nsec");
relation = dns_name_fullcompare(name, nsecname, &order, &olabels);
if (order < 0) {
/*
* The name is not within the NSEC range.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC does not cover name, before NSEC");
return (ISC_R_IGNORE);
}
if (order == 0) {
/*
* The names are the same.
*/
atparent = dns_rdatatype_atparent(val->event->type);
ns = dns_nsec_typepresent(&rdata, dns_rdatatype_ns);
soa = dns_nsec_typepresent(&rdata, dns_rdatatype_soa);
if (ns && !soa) {
if (!atparent) {
/*
* This NSEC record is from somewhere higher in
* the DNS, and at the parent of a delegation.
* It can not be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring parent nsec");
return (ISC_R_IGNORE);
}
} else if (atparent && ns && soa) {
/*
* This NSEC record is from the child.
* It can not be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring child nsec");
return (ISC_R_IGNORE);
}
if (val->event->type == dns_rdatatype_cname ||
val->event->type == dns_rdatatype_nxt ||
val->event->type == dns_rdatatype_nsec ||
val->event->type == dns_rdatatype_key ||
!dns_nsec_typepresent(&rdata, dns_rdatatype_cname)) {
*exists = ISC_TRUE;
*data = dns_nsec_typepresent(&rdata, val->event->type);
validator_log(val, ISC_LOG_DEBUG(3),
"nsec proves name exists (owner) data=%d",
*data);
return (ISC_R_SUCCESS);
}
validator_log(val, ISC_LOG_DEBUG(3), "NSEC proves CNAME exists");
return (ISC_R_IGNORE);
}
if (relation == dns_namereln_subdomain &&
dns_nsec_typepresent(&rdata, dns_rdatatype_ns) &&
!dns_nsec_typepresent(&rdata, dns_rdatatype_soa))
{
/*
* This NSEC record is from somewhere higher in
* the DNS, and at the parent of a delegation.
* It can not be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3), "ignoring parent nsec");
return (ISC_R_IGNORE);
}
result = dns_rdata_tostruct(&rdata, &nsec, NULL);
if (result != ISC_R_SUCCESS)
return (result);
relation = dns_name_fullcompare(&nsec.next, name, &order, &nlabels);
if (order == 0) {
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring nsec matches next name");
return (ISC_R_IGNORE);
}
if (order < 0 && !dns_name_issubdomain(nsecname, &nsec.next)) {
/*
* The name is not within the NSEC range.
*/
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring nsec because name is past end of range");
return (ISC_R_IGNORE);
}
if (order > 0 && relation == dns_namereln_subdomain) {
validator_log(val, ISC_LOG_DEBUG(3),
"nsec proves name exist (empty)");
dns_rdata_freestruct(&nsec);
*exists = ISC_TRUE;
*data = ISC_FALSE;
return (ISC_R_SUCCESS);
}
if (wild != NULL) {
dns_name_t common;
dns_name_init(&common, NULL);
if (olabels > nlabels) {
labels = dns_name_countlabels(nsecname);
dns_name_getlabelsequence(nsecname, labels - olabels,
olabels, &common);
} else {
labels = dns_name_countlabels(&nsec.next);
dns_name_getlabelsequence(&nsec.next, labels - nlabels,
nlabels, &common);
}
result = dns_name_concatenate(dns_wildcardname, &common,
wild, NULL);
if (result != ISC_R_SUCCESS) {
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3),
"failure generating wildcard name");
return (result);
}
}
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3), "nsec range ok");
*exists = ISC_FALSE;
return (ISC_R_SUCCESS);
}
static isc_result_t
nsec3noexistnodata(dns_validator_t *val, dns_name_t* name,
dns_name_t *nsec3name, dns_rdataset_t *nsec3set,
dns_name_t *zonename, isc_boolean_t *exists,
isc_boolean_t *data, isc_boolean_t *optout,
isc_boolean_t *unknown, isc_boolean_t *setclosest,
isc_boolean_t *setnearest, dns_name_t *closest,
dns_name_t *nearest)
{
char namebuf[DNS_NAME_FORMATSIZE];
dns_fixedname_t fzone;
dns_fixedname_t qfixed;
dns_label_t hashlabel;
dns_name_t *qname;
dns_name_t *zone;
dns_rdata_nsec3_t nsec3;
dns_rdata_t rdata = DNS_RDATA_INIT;
int order;
int scope;
isc_boolean_t atparent;
isc_boolean_t first;
isc_boolean_t ns;
isc_boolean_t soa;
isc_buffer_t buffer;
isc_result_t answer = ISC_R_IGNORE;
isc_result_t result;
unsigned char hash[NSEC3_MAX_HASH_LENGTH];
unsigned char owner[NSEC3_MAX_HASH_LENGTH];
unsigned int length;
unsigned int qlabels;
unsigned int zlabels;
REQUIRE((exists == NULL && data == NULL) ||
(exists != NULL && data != NULL));
REQUIRE(nsec3set != NULL && nsec3set->type == dns_rdatatype_nsec3);
REQUIRE((setclosest == NULL && closest == NULL) ||
(setclosest != NULL && closest != NULL));
REQUIRE((setnearest == NULL && nearest == NULL) ||
(setnearest != NULL && nearest != NULL));
result = dns_rdataset_first(nsec3set);
if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"failure processing NSEC3 set");
return (result);
}
dns_rdataset_current(nsec3set, &rdata);
result = dns_rdata_tostruct(&rdata, &nsec3, NULL);
if (result != ISC_R_SUCCESS)
return (result);
validator_log(val, ISC_LOG_DEBUG(3), "looking for relevant NSEC3");
dns_fixedname_init(&fzone);
zone = dns_fixedname_name(&fzone);
zlabels = dns_name_countlabels(nsec3name);
/*
* NSEC3 records must have two or more labels to be valid.
*/
if (zlabels < 2)
return (ISC_R_IGNORE);
/*
* Strip off the NSEC3 hash to get the zone.
*/
zlabels--;
dns_name_split(nsec3name, zlabels, NULL, zone);
/*
* If not below the zone name we can ignore this record.
*/
if (!dns_name_issubdomain(name, zone))
return (ISC_R_IGNORE);
/*
* Is this zone the same or deeper than the current zone?
*/
if (dns_name_countlabels(zonename) == 0 ||
dns_name_issubdomain(zone, zonename))
dns_name_copy(zone, zonename, NULL);
if (!dns_name_equal(zone, zonename))
return (ISC_R_IGNORE);
/*
* Are we only looking for the most enclosing zone?
*/
if (exists == NULL || data == NULL)
return (ISC_R_SUCCESS);
/*
* Only set unknown once we are sure that this NSEC3 is from
* the deepest covering zone.
*/
if (!dns_nsec3_supportedhash(nsec3.hash)) {
if (unknown != NULL)
*unknown = ISC_TRUE;
return (ISC_R_IGNORE);
}
/*
* Recover the hash from the first label.
*/
dns_name_getlabel(nsec3name, 0, &hashlabel);
isc_region_consume(&hashlabel, 1);
isc_buffer_init(&buffer, owner, sizeof(owner));
result = isc_base32hex_decoderegion(&hashlabel, &buffer);
if (result != ISC_R_SUCCESS)
return (result);
/*
* The hash lengths should match. If not ignore the record.
*/
if (isc_buffer_usedlength(&buffer) != nsec3.next_length)
return (ISC_R_IGNORE);
/*
* Work out what this NSEC3 covers.
* Inside (<0) or outside (>=0).
*/
scope = memcmp(owner, nsec3.next, nsec3.next_length);
/*
* Prepare to compute all the hashes.
*/
dns_fixedname_init(&qfixed);
qname = dns_fixedname_name(&qfixed);
dns_name_downcase(name, qname, NULL);
qlabels = dns_name_countlabels(qname);
first = ISC_TRUE;
while (qlabels >= zlabels) {
length = isc_iterated_hash(hash, nsec3.hash, nsec3.iterations,
nsec3.salt, nsec3.salt_length,
qname->ndata, qname->length);
/*
* The computed hash length should match.
*/
if (length != nsec3.next_length) {
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring NSEC bad length %u vs %u",
length, nsec3.next_length);
return (ISC_R_IGNORE);
}
order = memcmp(hash, owner, length);
if (first && order == 0) {
/*
* The hashes are the same.
*/
atparent = dns_rdatatype_atparent(val->event->type);
ns = dns_nsec3_typepresent(&rdata, dns_rdatatype_ns);
soa = dns_nsec3_typepresent(&rdata, dns_rdatatype_soa);
if (ns && !soa) {
if (!atparent) {
/*
* This NSEC3 record is from somewhere
* higher in the DNS, and at the
* parent of a delegation. It can not
* be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring parent NSEC3");
return (ISC_R_IGNORE);
}
} else if (atparent && ns && soa) {
/*
* This NSEC3 record is from the child.
* It can not be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring child NSEC3");
return (ISC_R_IGNORE);
}
if (val->event->type == dns_rdatatype_cname ||
val->event->type == dns_rdatatype_nxt ||
val->event->type == dns_rdatatype_nsec ||
val->event->type == dns_rdatatype_key ||
!dns_nsec3_typepresent(&rdata, dns_rdatatype_cname)) {
*exists = ISC_TRUE;
*data = dns_nsec3_typepresent(&rdata,
val->event->type);
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC3 proves name exists (owner) "
"data=%d", *data);
return (ISC_R_SUCCESS);
}
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC3 proves CNAME exists");
return (ISC_R_IGNORE);
}
if (order == 0 &&
dns_nsec3_typepresent(&rdata, dns_rdatatype_ns) &&
!dns_nsec3_typepresent(&rdata, dns_rdatatype_soa))
{
/*
* This NSEC3 record is from somewhere higher in
* the DNS, and at the parent of a delegation.
* It can not be legitimately used here.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"ignoring parent NSEC3");
return (ISC_R_IGNORE);
}
/*
* Potential closest encloser.
*/
if (order == 0) {
if (closest != NULL &&
(dns_name_countlabels(closest) == 0 ||
dns_name_issubdomain(qname, closest)) &&
!dns_nsec3_typepresent(&rdata, dns_rdatatype_ds) &&
!dns_nsec3_typepresent(&rdata, dns_rdatatype_dname) &&
(dns_nsec3_typepresent(&rdata, dns_rdatatype_soa) ||
!dns_nsec3_typepresent(&rdata, dns_rdatatype_ns)))
{
dns_name_format(qname, namebuf,
sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC3 indicates potential "
"closest encloser: '%s'",
namebuf);
dns_name_copy(qname, closest, NULL);
*setclosest = ISC_TRUE;
}
dns_name_format(qname, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC3 at super-domain %s", namebuf);
return (answer);
}
/*
* Find if the name does not exist.
*
* We continue as we need to find the name closest to the
* closest encloser that doesn't exist.
*
* We also need to continue to ensure that we are not
* proving the non-existence of a record in a sub-zone.
* If that would be the case we will return ISC_R_IGNORE
* above.
*/
if ((scope < 0 && order > 0 &&
memcmp(hash, nsec3.next, length) < 0) ||
(scope >= 0 && (order > 0 ||
memcmp(hash, nsec3.next, length) < 0)))
{
char namebuf[DNS_NAME_FORMATSIZE];
dns_name_format(qname, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3), "NSEC3 proves "
"name does not exist: '%s'", namebuf);
if (nearest != NULL &&
(dns_name_countlabels(nearest) == 0 ||
dns_name_issubdomain(nearest, qname))) {
dns_name_copy(qname, nearest, NULL);
*setnearest = ISC_TRUE;
}
*exists = ISC_FALSE;
*data = ISC_FALSE;
if (optout != NULL) {
if ((nsec3.flags & DNS_NSEC3FLAG_OPTOUT) != 0)
validator_log(val, ISC_LOG_DEBUG(3),
"NSEC3 indicates optout");
*optout =
ISC_TF(nsec3.flags & DNS_NSEC3FLAG_OPTOUT);
}
answer = ISC_R_SUCCESS;
}
qlabels--;
if (qlabels > 0)
dns_name_split(qname, qlabels, NULL, qname);
first = ISC_FALSE;
}
return (answer);
}
/*%
* Callback for when NSEC records have been validated.
*
* Looks for NOQNAME, NODATA and OPTOUT proofs.
*
* Resumes nsecvalidate.
*/
static void
authvalidated(isc_task_t *task, isc_event_t *event) {
dns_validatorevent_t *devent;
dns_validator_t *val;
dns_rdataset_t *rdataset;
isc_boolean_t want_destroy;
isc_result_t result;
isc_boolean_t exists, data;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_VALIDATORDONE);
devent = (dns_validatorevent_t *)event;
rdataset = devent->rdataset;
val = devent->ev_arg;
result = devent->result;
dns_validator_destroy(&val->subvalidator);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in authvalidated");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"authvalidated: got %s",
isc_result_totext(result));
if (result == DNS_R_BROKENCHAIN)
val->authfail++;
if (result == ISC_R_CANCELED)
validator_done(val, result);
else {
result = nsecvalidate(val, ISC_TRUE);
if (result != DNS_R_WAIT)
validator_done(val, result);
}
} else {
dns_name_t **proofs = val->event->proofs;
dns_name_t *wild = dns_fixedname_name(&val->wild);
if (rdataset->trust == dns_trust_secure)
val->seensig = ISC_TRUE;
if (rdataset->type == dns_rdatatype_nsec &&
rdataset->trust == dns_trust_secure &&
(NEEDNODATA(val) || NEEDNOQNAME(val)) &&
!FOUNDNODATA(val) && !FOUNDNOQNAME(val) &&
nsecnoexistnodata(val, val->event->name, devent->name,
rdataset, &exists, &data, wild)
== ISC_R_SUCCESS)
{
if (exists && !data) {
val->attributes |= VALATTR_FOUNDNODATA;
if (NEEDNODATA(val))
proofs[DNS_VALIDATOR_NODATAPROOF] =
devent->name;
}
if (!exists) {
val->attributes |= VALATTR_FOUNDNOQNAME;
val->attributes |= VALATTR_FOUNDCLOSEST;
/*
* The NSEC noqname proof also contains
* the closest encloser.
*/
if (NEEDNOQNAME(val))
proofs[DNS_VALIDATOR_NOQNAMEPROOF] =
devent->name;
}
}
result = nsecvalidate(val, ISC_TRUE);
if (result != DNS_R_WAIT)
validator_done(val, result);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
/*
* Free stuff from the event.
*/
isc_event_free(&event);
}
/*%
* Looks for the requested name and type in the view (zones and cache).
*
* When looking for a DLV record also checks to make sure the NSEC record
* returns covers the query name as part of aggressive negative caching.
*
* Returns:
* \li ISC_R_SUCCESS
* \li ISC_R_NOTFOUND
* \li DNS_R_NCACHENXDOMAIN
* \li DNS_R_NCACHENXRRSET
* \li DNS_R_NXRRSET
* \li DNS_R_NXDOMAIN
* \li DNS_R_BROKENCHAIN
*/
static inline isc_result_t
view_find(dns_validator_t *val, dns_name_t *name, dns_rdatatype_t type) {
dns_fixedname_t fixedname;
dns_name_t *foundname;
dns_rdata_nsec_t nsec;
dns_rdata_t rdata = DNS_RDATA_INIT;
isc_result_t result;
unsigned int options;
isc_time_t now;
char buf1[DNS_NAME_FORMATSIZE];
char buf2[DNS_NAME_FORMATSIZE];
char buf3[DNS_NAME_FORMATSIZE];
char namebuf[DNS_NAME_FORMATSIZE];
char typebuf[DNS_RDATATYPE_FORMATSIZE];
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
if (val->view->zonetable == NULL)
return (ISC_R_CANCELED);
if (isc_time_now(&now) == ISC_R_SUCCESS &&
dns_resolver_getbadcache(val->view->resolver, name, type, &now)) {
dns_name_format(name, namebuf, sizeof(namebuf));
dns_rdatatype_format(type, typebuf, sizeof(typebuf));
validator_log(val, ISC_LOG_INFO, "bad cache hit (%s/%s)",
namebuf, typebuf);
return (DNS_R_BROKENCHAIN);
}
options = DNS_DBFIND_PENDINGOK;
if (type == dns_rdatatype_dlv)
options |= DNS_DBFIND_COVERINGNSEC;
dns_fixedname_init(&fixedname);
foundname = dns_fixedname_name(&fixedname);
result = dns_view_find(val->view, name, type, 0, options,
ISC_FALSE, NULL, NULL, foundname,
&val->frdataset, &val->fsigrdataset);
if (result == DNS_R_NXDOMAIN) {
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
} else if (result == DNS_R_COVERINGNSEC) {
validator_log(val, ISC_LOG_DEBUG(3), "DNS_R_COVERINGNSEC");
/*
* Check if the returned NSEC covers the name.
*/
INSIST(type == dns_rdatatype_dlv);
if (val->frdataset.trust != dns_trust_secure) {
validator_log(val, ISC_LOG_DEBUG(3),
"covering nsec: trust %s",
dns_trust_totext(val->frdataset.trust));
goto notfound;
}
result = dns_rdataset_first(&val->frdataset);
if (result != ISC_R_SUCCESS)
goto notfound;
dns_rdataset_current(&val->frdataset, &rdata);
if (dns_nsec_typepresent(&rdata, dns_rdatatype_ns) &&
!dns_nsec_typepresent(&rdata, dns_rdatatype_soa)) {
/* Parent NSEC record. */
if (dns_name_issubdomain(name, foundname)) {
validator_log(val, ISC_LOG_DEBUG(3),
"covering nsec: for parent");
goto notfound;
}
}
result = dns_rdata_tostruct(&rdata, &nsec, NULL);
if (result != ISC_R_SUCCESS)
goto notfound;
if (dns_name_compare(foundname, &nsec.next) >= 0) {
/* End of zone chain. */
if (!dns_name_issubdomain(name, &nsec.next)) {
/*
* XXXMPA We could look for a parent NSEC
* at nsec.next and if found retest with
* this NSEC.
*/
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3),
"covering nsec: not in zone");
goto notfound;
}
} else if (dns_name_compare(name, &nsec.next) >= 0) {
/*
* XXXMPA We could check if this NSEC is at a zone
* apex and if the qname is not below it and look for
* a parent NSEC with the same name. This requires
* that we can cache both NSEC records which we
* currently don't support.
*/
dns_rdata_freestruct(&nsec);
validator_log(val, ISC_LOG_DEBUG(3),
"covering nsec: not in range");
goto notfound;
}
if (isc_log_wouldlog(dns_lctx,ISC_LOG_DEBUG(3))) {
dns_name_format(name, buf1, sizeof buf1);
dns_name_format(foundname, buf2, sizeof buf2);
dns_name_format(&nsec.next, buf3, sizeof buf3);
validator_log(val, ISC_LOG_DEBUG(3),
"covering nsec found: '%s' '%s' '%s'",
buf1, buf2, buf3);
}
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
dns_rdata_freestruct(&nsec);
result = DNS_R_NCACHENXDOMAIN;
} else if (result != ISC_R_SUCCESS &&
result != DNS_R_NCACHENXDOMAIN &&
result != DNS_R_NCACHENXRRSET &&
result != DNS_R_EMPTYNAME &&
result != DNS_R_NXRRSET &&
result != ISC_R_NOTFOUND) {
goto notfound;
}
return (result);
notfound:
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
return (ISC_R_NOTFOUND);
}
/*%
* Checks to make sure we are not going to loop. As we use a SHARED fetch
* the validation process will stall if looping was to occur.
*/
static inline isc_boolean_t
check_deadlock(dns_validator_t *val, dns_name_t *name, dns_rdatatype_t type,
dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset)
{
dns_validator_t *parent;
for (parent = val; parent != NULL; parent = parent->parent) {
if (parent->event != NULL &&
parent->event->type == type &&
dns_name_equal(parent->event->name, name) &&
/*
* As NSEC3 records are meta data you sometimes
* need to prove a NSEC3 record which says that
* itself doesn't exist.
*/
(parent->event->type != dns_rdatatype_nsec3 ||
rdataset == NULL || sigrdataset == NULL ||
parent->event->message == NULL ||
parent->event->rdataset != NULL ||
parent->event->sigrdataset != NULL))
{
validator_log(val, ISC_LOG_DEBUG(3),
"continuing validation would lead to "
"deadlock: aborting validation");
return (ISC_TRUE);
}
}
return (ISC_FALSE);
}
/*%
* Start a fetch for the requested name and type.
*/
static inline isc_result_t
create_fetch(dns_validator_t *val, dns_name_t *name, dns_rdatatype_t type,
isc_taskaction_t callback, const char *caller)
{
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
if (check_deadlock(val, name, type, NULL, NULL)) {
validator_log(val, ISC_LOG_DEBUG(3),
"deadlock found (create_fetch)");
return (DNS_R_NOVALIDSIG);
}
validator_logcreate(val, name, type, caller, "fetch");
return (dns_resolver_createfetch(val->view->resolver, name, type,
NULL, NULL, NULL, 0,
val->event->ev_sender,
callback, val,
&val->frdataset,
&val->fsigrdataset,
&val->fetch));
}
/*%
* Start a subvalidation process.
*/
static inline isc_result_t
create_validator(dns_validator_t *val, dns_name_t *name, dns_rdatatype_t type,
dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
isc_taskaction_t action, const char *caller)
{
isc_result_t result;
if (check_deadlock(val, name, type, rdataset, sigrdataset)) {
validator_log(val, ISC_LOG_DEBUG(3),
"deadlock found (create_validator)");
return (DNS_R_NOVALIDSIG);
}
validator_logcreate(val, name, type, caller, "validator");
result = dns_validator_create(val->view, name, type,
rdataset, sigrdataset, NULL, 0,
val->task, action, val,
&val->subvalidator);
if (result == ISC_R_SUCCESS) {
val->subvalidator->parent = val;
val->subvalidator->depth = val->depth + 1;
}
return (result);
}
/*%
* Try to find a key that could have signed 'siginfo' among those
* in 'rdataset'. If found, build a dst_key_t for it and point
* val->key at it.
*
* If val->key is non-NULL, this returns the next matching key.
*/
static isc_result_t
get_dst_key(dns_validator_t *val, dns_rdata_rrsig_t *siginfo,
dns_rdataset_t *rdataset)
{
isc_result_t result;
isc_buffer_t b;
dns_rdata_t rdata = DNS_RDATA_INIT;
dst_key_t *oldkey = val->key;
isc_boolean_t foundold;
if (oldkey == NULL)
foundold = ISC_TRUE;
else {
foundold = ISC_FALSE;
val->key = NULL;
}
result = dns_rdataset_first(rdataset);
if (result != ISC_R_SUCCESS)
goto failure;
do {
dns_rdataset_current(rdataset, &rdata);
isc_buffer_init(&b, rdata.data, rdata.length);
isc_buffer_add(&b, rdata.length);
INSIST(val->key == NULL);
result = dst_key_fromdns(&siginfo->signer, rdata.rdclass, &b,
val->view->mctx, &val->key);
if (result != ISC_R_SUCCESS)
goto failure;
if (siginfo->algorithm ==
(dns_secalg_t)dst_key_alg(val->key) &&
siginfo->keyid ==
(dns_keytag_t)dst_key_id(val->key) &&
dst_key_iszonekey(val->key))
{
if (foundold)
/*
* This is the key we're looking for.
*/
return (ISC_R_SUCCESS);
else if (dst_key_compare(oldkey, val->key) == ISC_TRUE)
{
foundold = ISC_TRUE;
dst_key_free(&oldkey);
}
}
dst_key_free(&val->key);
dns_rdata_reset(&rdata);
result = dns_rdataset_next(rdataset);
} while (result == ISC_R_SUCCESS);
if (result == ISC_R_NOMORE)
result = ISC_R_NOTFOUND;
failure:
if (oldkey != NULL)
dst_key_free(&oldkey);
return (result);
}
/*%
* Get the key that generated this signature.
*/
static isc_result_t
get_key(dns_validator_t *val, dns_rdata_rrsig_t *siginfo) {
isc_result_t result;
unsigned int nlabels;
int order;
dns_namereln_t namereln;
/*
* Is the signer name appropriate for this signature?
*
* The signer name must be at the same level as the owner name
* or closer to the DNS root.
*/
namereln = dns_name_fullcompare(val->event->name, &siginfo->signer,
&order, &nlabels);
if (namereln != dns_namereln_subdomain &&
namereln != dns_namereln_equal)
return (DNS_R_CONTINUE);
if (namereln == dns_namereln_equal) {
/*
* If this is a self-signed keyset, it must not be a zone key
* (since get_key is not called from validatezonekey).
*/
if (val->event->rdataset->type == dns_rdatatype_dnskey)
return (DNS_R_CONTINUE);
/*
* Records appearing in the parent zone at delegation
* points cannot be self-signed.
*/
if (dns_rdatatype_atparent(val->event->rdataset->type))
return (DNS_R_CONTINUE);
} else {
/*
* SOA and NS RRsets can only be signed by a key with
* the same name.
*/
if (val->event->rdataset->type == dns_rdatatype_soa ||
val->event->rdataset->type == dns_rdatatype_ns) {
const char *typename;
if (val->event->rdataset->type == dns_rdatatype_soa)
typename = "SOA";
else
typename = "NS";
validator_log(val, ISC_LOG_DEBUG(3),
"%s signer mismatch", typename);
return (DNS_R_CONTINUE);
}
}
/*
* Do we know about this key?
*/
result = view_find(val, &siginfo->signer, dns_rdatatype_dnskey);
if (result == ISC_R_SUCCESS) {
/*
* We have an rrset for the given keyname.
*/
val->keyset = &val->frdataset;
if ((DNS_TRUST_PENDING(val->frdataset.trust) ||
DNS_TRUST_ANSWER(val->frdataset.trust)) &&
dns_rdataset_isassociated(&val->fsigrdataset))
{
/*
* We know the key but haven't validated it yet or
* we have a key of trust answer but a DS/DLV
* record for the zone may have been added.
*/
result = create_validator(val, &siginfo->signer,
dns_rdatatype_dnskey,
&val->frdataset,
&val->fsigrdataset,
keyvalidated,
"get_key");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
} else if (DNS_TRUST_PENDING(val->frdataset.trust)) {
/*
* Having a pending key with no signature means that
* something is broken.
*/
result = DNS_R_CONTINUE;
} else if (val->frdataset.trust < dns_trust_secure) {
/*
* The key is legitimately insecure. There's no
* point in even attempting verification.
*/
val->key = NULL;
result = ISC_R_SUCCESS;
} else {
/*
* See if we've got the key used in the signature.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"keyset with trust %s",
dns_trust_totext(val->frdataset.trust));
result = get_dst_key(val, siginfo, val->keyset);
if (result != ISC_R_SUCCESS) {
/*
* Either the key we're looking for is not
* in the rrset, or something bad happened.
* Give up.
*/
result = DNS_R_CONTINUE;
}
}
} else if (result == ISC_R_NOTFOUND) {
/*
* We don't know anything about this key.
*/
result = create_fetch(val, &siginfo->signer,
dns_rdatatype_dnskey,
fetch_callback_validator, "get_key");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
} else if (result == DNS_R_NCACHENXDOMAIN ||
result == DNS_R_NCACHENXRRSET ||
result == DNS_R_EMPTYNAME ||
result == DNS_R_NXDOMAIN ||
result == DNS_R_NXRRSET)
{
/*
* This key doesn't exist.
*/
result = DNS_R_CONTINUE;
} else if (result == DNS_R_BROKENCHAIN)
return (result);
if (dns_rdataset_isassociated(&val->frdataset) &&
val->keyset != &val->frdataset)
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
return (result);
}
static dns_keytag_t
compute_keytag(dns_rdata_t *rdata, dns_rdata_dnskey_t *key) {
isc_region_t r;
dns_rdata_toregion(rdata, &r);
return (dst_region_computeid(&r, key->algorithm));
}
/*%
* Is this keyset self-signed?
*/
static isc_boolean_t
isselfsigned(dns_validator_t *val) {
dns_fixedname_t fixed;
dns_rdataset_t *rdataset, *sigrdataset;
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_rdata_t sigrdata = DNS_RDATA_INIT;
dns_rdata_dnskey_t key;
dns_rdata_rrsig_t sig;
dns_keytag_t keytag;
dns_name_t *name;
isc_result_t result;
dst_key_t *dstkey;
isc_mem_t *mctx;
isc_boolean_t answer = ISC_FALSE;
rdataset = val->event->rdataset;
sigrdataset = val->event->sigrdataset;
name = val->event->name;
mctx = val->view->mctx;
INSIST(rdataset->type == dns_rdatatype_dnskey);
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset))
{
dns_rdata_reset(&rdata);
dns_rdataset_current(rdataset, &rdata);
result = dns_rdata_tostruct(&rdata, &key, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
keytag = compute_keytag(&rdata, &key);
for (result = dns_rdataset_first(sigrdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(sigrdataset))
{
dns_rdata_reset(&sigrdata);
dns_rdataset_current(sigrdataset, &sigrdata);
result = dns_rdata_tostruct(&sigrdata, &sig, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (sig.algorithm != key.algorithm ||
sig.keyid != keytag ||
!dns_name_equal(name, &sig.signer))
continue;
dstkey = NULL;
result = dns_dnssec_keyfromrdata(name, &rdata, mctx,
&dstkey);
if (result != ISC_R_SUCCESS)
continue;
result = dns_dnssec_verify2(name, rdataset, dstkey,
ISC_TRUE, mctx, &sigrdata,
dns_fixedname_name(&fixed));
dst_key_free(&dstkey);
if (result != ISC_R_SUCCESS)
continue;
if ((key.flags & DNS_KEYFLAG_REVOKE) == 0) {
answer = ISC_TRUE;
continue;
}
dns_view_untrust(val->view, name, &key, mctx);
}
}
return (answer);
}
/*%
* Attempt to verify the rdataset using the given key and rdata (RRSIG).
* The signature was good and from a wildcard record and the QNAME does
* not match the wildcard we need to look for a NOQNAME proof.
*
* Returns:
* \li ISC_R_SUCCESS if the verification succeeds.
* \li Others if the verification fails.
*/
static isc_result_t
verify(dns_validator_t *val, dst_key_t *key, dns_rdata_t *rdata,
isc_uint16_t keyid)
{
isc_result_t result;
dns_fixedname_t fixed;
isc_boolean_t ignore = ISC_FALSE;
val->attributes |= VALATTR_TRIEDVERIFY;
dns_fixedname_init(&fixed);
again:
result = dns_dnssec_verify2(val->event->name, val->event->rdataset,
key, ignore, val->view->mctx, rdata,
dns_fixedname_name(&fixed));
if (result == DNS_R_SIGEXPIRED && val->view->acceptexpired) {
ignore = ISC_TRUE;
goto again;
}
if (ignore && (result == ISC_R_SUCCESS || result == DNS_R_FROMWILDCARD))
validator_log(val, ISC_LOG_INFO,
"accepted expired %sRRSIG (keyid=%u)",
(result == DNS_R_FROMWILDCARD) ?
"wildcard " : "", keyid);
else
validator_log(val, ISC_LOG_DEBUG(3),
"verify rdataset (keyid=%u): %s",
keyid, isc_result_totext(result));
if (result == DNS_R_FROMWILDCARD) {
if (!dns_name_equal(val->event->name,
dns_fixedname_name(&fixed)))
val->attributes |= VALATTR_NEEDNOQNAME;
result = ISC_R_SUCCESS;
}
return (result);
}
/*%
* Attempts positive response validation of a normal RRset.
*
* Returns:
* \li ISC_R_SUCCESS Validation completed successfully
* \li DNS_R_WAIT Validation has started but is waiting
* for an event.
* \li Other return codes are possible and all indicate failure.
*/
static isc_result_t
validate(dns_validator_t *val, isc_boolean_t resume) {
isc_result_t result;
dns_validatorevent_t *event;
dns_rdata_t rdata = DNS_RDATA_INIT;
/*
* Caller must be holding the validator lock.
*/
event = val->event;
if (resume) {
/*
* We already have a sigrdataset.
*/
result = ISC_R_SUCCESS;
validator_log(val, ISC_LOG_DEBUG(3), "resuming validate");
} else {
result = dns_rdataset_first(event->sigrdataset);
}
for (;
result == ISC_R_SUCCESS;
result = dns_rdataset_next(event->sigrdataset))
{
dns_rdata_reset(&rdata);
dns_rdataset_current(event->sigrdataset, &rdata);
if (val->siginfo == NULL) {
val->siginfo = isc_mem_get(val->view->mctx,
sizeof(*val->siginfo));
if (val->siginfo == NULL)
return (ISC_R_NOMEMORY);
}
result = dns_rdata_tostruct(&rdata, val->siginfo, NULL);
if (result != ISC_R_SUCCESS)
return (result);
/*
* At this point we could check that the signature algorithm
* was known and "sufficiently good".
*/
if (!dns_resolver_algorithm_supported(val->view->resolver,
event->name,
val->siginfo->algorithm)) {
resume = ISC_FALSE;
continue;
}
if (!resume) {
result = get_key(val, val->siginfo);
if (result == DNS_R_CONTINUE)
continue; /* Try the next SIG RR. */
if (result != ISC_R_SUCCESS)
return (result);
}
/*
* There isn't a secure DNSKEY for this signature so move
* onto the next RRSIG.
*/
if (val->key == NULL) {
resume = ISC_FALSE;
continue;
}
do {
result = verify(val, val->key, &rdata,
val->siginfo->keyid);
if (result == ISC_R_SUCCESS)
break;
if (val->keynode != NULL) {
dns_keynode_t *nextnode = NULL;
result = dns_keytable_findnextkeynode(
val->keytable,
val->keynode,
&nextnode);
dns_keytable_detachkeynode(val->keytable,
&val->keynode);
val->keynode = nextnode;
if (result != ISC_R_SUCCESS) {
val->key = NULL;
break;
}
val->key = dns_keynode_key(val->keynode);
if (val->key == NULL)
break;
} else {
if (get_dst_key(val, val->siginfo, val->keyset)
!= ISC_R_SUCCESS)
break;
}
} while (1);
if (result != ISC_R_SUCCESS)
validator_log(val, ISC_LOG_DEBUG(3),
"failed to verify rdataset");
else {
isc_uint32_t ttl;
isc_stdtime_t now;
isc_stdtime_get(&now);
ttl = ISC_MIN(event->rdataset->ttl,
ISC_MIN(val->siginfo->originalttl,
val->siginfo->timeexpire - now));
event->rdataset->ttl = ttl;
event->sigrdataset->ttl = ttl;
}
if (val->keynode != NULL)
dns_keytable_detachkeynode(val->keytable,
&val->keynode);
else {
if (val->key != NULL)
dst_key_free(&val->key);
if (val->keyset != NULL) {
dns_rdataset_disassociate(val->keyset);
val->keyset = NULL;
}
}
val->key = NULL;
if (NEEDNOQNAME(val)) {
if (val->event->message == NULL) {
validator_log(val, ISC_LOG_DEBUG(3),
"no message available for noqname proof");
return (DNS_R_NOVALIDSIG);
}
validator_log(val, ISC_LOG_DEBUG(3),
"looking for noqname proof");
return (nsecvalidate(val, ISC_FALSE));
} else if (result == ISC_R_SUCCESS) {
marksecure(event);
validator_log(val, ISC_LOG_DEBUG(3),
"marking as secure, "
"noqname proof not needed");
return (result);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"verify failure: %s",
isc_result_totext(result));
resume = ISC_FALSE;
}
}
if (result != ISC_R_NOMORE) {
validator_log(val, ISC_LOG_DEBUG(3),
"failed to iterate signatures: %s",
isc_result_totext(result));
return (result);
}
validator_log(val, ISC_LOG_INFO, "no valid signature found");
return (DNS_R_NOVALIDSIG);
}
/*%
* Check whether this DNSKEY (keyrdata) signed the DNSKEY RRset
* (val->event->rdataset).
*/
static isc_result_t
checkkey(dns_validator_t *val, dns_rdata_t *keyrdata, isc_uint16_t keyid,
dns_secalg_t algorithm)
{
dns_rdata_rrsig_t sig;
dst_key_t *dstkey = NULL;
isc_result_t result;
for (result = dns_rdataset_first(val->event->sigrdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(val->event->sigrdataset))
{
dns_rdata_t rdata = DNS_RDATA_INIT;
dns_rdataset_current(val->event->sigrdataset, &rdata);
result = dns_rdata_tostruct(&rdata, &sig, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (keyid != sig.keyid || algorithm != sig.algorithm)
continue;
if (dstkey == NULL) {
result = dns_dnssec_keyfromrdata(val->event->name,
keyrdata,
val->view->mctx,
&dstkey);
if (result != ISC_R_SUCCESS)
/*
* This really shouldn't happen, but...
*/
continue;
}
result = verify(val, dstkey, &rdata, sig.keyid);
if (result == ISC_R_SUCCESS)
break;
}
if (dstkey != NULL)
dst_key_free(&dstkey);
return (result);
}
/*%
* Find the DNSKEY that corresponds to the DS.
*/
static isc_result_t
keyfromds(dns_validator_t *val, dns_rdataset_t *rdataset, dns_rdata_t *dsrdata,
isc_uint8_t digest, isc_uint16_t keyid, dns_secalg_t algorithm,
dns_rdata_t *keyrdata)
{
dns_keytag_t keytag;
dns_rdata_dnskey_t key;
isc_result_t result;
unsigned char dsbuf[DNS_DS_BUFFERSIZE];
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset))
{
dns_rdata_t newdsrdata = DNS_RDATA_INIT;
dns_rdata_reset(keyrdata);
dns_rdataset_current(rdataset, keyrdata);
result = dns_rdata_tostruct(keyrdata, &key, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
keytag = compute_keytag(keyrdata, &key);
if (keyid != keytag || algorithm != key.algorithm)
continue;
dns_rdata_reset(&newdsrdata);
result = dns_ds_buildrdata(val->event->name, keyrdata, digest,
dsbuf, &newdsrdata);
if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"dns_ds_buildrdata() -> %s",
dns_result_totext(result));
continue;
}
if (dns_rdata_compare(dsrdata, &newdsrdata) == 0)
break;
}
return (result);
}
/*%
* Validate the DNSKEY RRset by looking for a DNSKEY that matches a
* DLV record and that also verifies the DNSKEY RRset.
*/
static isc_result_t
dlv_validatezonekey(dns_validator_t *val) {
dns_rdata_dlv_t dlv;
dns_rdata_t dlvrdata = DNS_RDATA_INIT;
dns_rdata_t keyrdata = DNS_RDATA_INIT;
dns_rdataset_t trdataset;
isc_boolean_t supported_algorithm;
isc_result_t result;
char digest_types[256];
validator_log(val, ISC_LOG_DEBUG(3), "dlv_validatezonekey");
/*
* Look through the DLV record and find the keys that can sign the
* key set and the matching signature. For each such key, attempt
* verification.
*/
supported_algorithm = ISC_FALSE;
/*
* If DNS_DSDIGEST_SHA256 is present we are required to prefer
* it over DNS_DSDIGEST_SHA1. This in practice means that we
* need to ignore DNS_DSDIGEST_SHA1 if a DNS_DSDIGEST_SHA256
* is present.
*/
memset(digest_types, 1, sizeof(digest_types));
for (result = dns_rdataset_first(&val->dlv);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&val->dlv)) {
dns_rdata_reset(&dlvrdata);
dns_rdataset_current(&val->dlv, &dlvrdata);
result = dns_rdata_tostruct(&dlvrdata, &dlv, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_resolver_algorithm_supported(val->view->resolver,
val->event->name,
dlv.algorithm))
continue;
if (dlv.digest_type == DNS_DSDIGEST_SHA256 &&
dlv.length == ISC_SHA256_DIGESTLENGTH) {
digest_types[DNS_DSDIGEST_SHA1] = 0;
break;
}
}
for (result = dns_rdataset_first(&val->dlv);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&val->dlv))
{
dns_rdata_reset(&dlvrdata);
dns_rdataset_current(&val->dlv, &dlvrdata);
result = dns_rdata_tostruct(&dlvrdata, &dlv, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_resolver_digest_supported(val->view->resolver,
dlv.digest_type))
continue;
if (digest_types[dlv.digest_type] == 0)
continue;
if (!dns_resolver_algorithm_supported(val->view->resolver,
val->event->name,
dlv.algorithm))
continue;
supported_algorithm = ISC_TRUE;
dns_rdataset_init(&trdataset);
dns_rdataset_clone(val->event->rdataset, &trdataset);
/*
* Convert to DLV to DS and find matching DNSKEY.
*/
dlvrdata.type = dns_rdatatype_ds;
result = keyfromds(val, &trdataset, &dlvrdata,
dlv.digest_type, dlv.key_tag,
dlv.algorithm, &keyrdata);
if (result != ISC_R_SUCCESS) {
dns_rdataset_disassociate(&trdataset);
validator_log(val, ISC_LOG_DEBUG(3),
"no DNSKEY matching DLV");
continue;
}
validator_log(val, ISC_LOG_DEBUG(3),
"Found matching DLV record: checking for signature");
/*
* Check that this DNSKEY signed the DNSKEY rrset.
*/
result = checkkey(val, &keyrdata, dlv.key_tag, dlv.algorithm);
dns_rdataset_disassociate(&trdataset);
if (result == ISC_R_SUCCESS)
break;
validator_log(val, ISC_LOG_DEBUG(3),
"no RRSIG matching DLV key");
}
if (result == ISC_R_SUCCESS) {
marksecure(val->event);
validator_log(val, ISC_LOG_DEBUG(3), "marking as secure (dlv)");
return (result);
} else if (result == ISC_R_NOMORE && !supported_algorithm) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure,"
"no supported algorithm/digest (dlv)");
return (DNS_R_MUSTBESECURE);
}
validator_log(val, ISC_LOG_DEBUG(3),
"no supported algorithm/digest (dlv)");
markanswer(val, "dlv_validatezonekey (2)");
return (ISC_R_SUCCESS);
} else
return (DNS_R_NOVALIDSIG);
}
/*%
* Attempts positive response validation of an RRset containing zone keys
* (i.e. a DNSKEY rrset).
*
* Returns:
* \li ISC_R_SUCCESS Validation completed successfully
* \li DNS_R_WAIT Validation has started but is waiting
* for an event.
* \li Other return codes are possible and all indicate failure.
*/
static isc_result_t
validatezonekey(dns_validator_t *val) {
isc_result_t result;
dns_validatorevent_t *event;
dns_rdataset_t trdataset;
dns_rdata_t dsrdata = DNS_RDATA_INIT;
dns_rdata_t keyrdata = DNS_RDATA_INIT;
dns_rdata_t sigrdata = DNS_RDATA_INIT;
char namebuf[DNS_NAME_FORMATSIZE];
dns_rdata_ds_t ds;
dns_rdata_rrsig_t sig;
dst_key_t *dstkey;
isc_boolean_t supported_algorithm;
isc_boolean_t atsep = ISC_FALSE;
char digest_types[256];
/*
* Caller must be holding the validator lock.
*/
event = val->event;
if (val->havedlvsep && val->dlv.trust >= dns_trust_secure &&
dns_name_equal(event->name, dns_fixedname_name(&val->dlvsep)))
return (dlv_validatezonekey(val));
if (val->dsset == NULL) {
/*
* We have a dlv sep. Skip looking up the SEP from
* {trusted,managed}-keys. If the dlv sep is for the
* root then it will have been handled above so we don't
* need to check whether val->event->name is "." prior to
* looking up the DS.
*/
if (val->havedlvsep)
goto find_ds;
/*
* First, see if this key was signed by a trusted key.
*/
for (result = dns_rdataset_first(val->event->sigrdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(val->event->sigrdataset))
{
dns_keynode_t *keynode = NULL;
dns_fixedname_t fixed;
dns_name_t *found;
dns_fixedname_init(&fixed);
found = dns_fixedname_name(&fixed);
dns_rdata_reset(&sigrdata);
dns_rdataset_current(val->event->sigrdataset,
&sigrdata);
result = dns_rdata_tostruct(&sigrdata, &sig, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_name_equal(val->event->name, &sig.signer))
continue;
result = dns_keytable_findkeynode(val->keytable,
val->event->name,
sig.algorithm,
sig.keyid, &keynode);
if (result == ISC_R_NOTFOUND &&
dns_keytable_finddeepestmatch(val->keytable,
val->event->name, found) != ISC_R_SUCCESS) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"not beneath secure root");
return (DNS_R_MUSTBESECURE);
} else
validator_log(val, ISC_LOG_DEBUG(3),
"not beneath secure root");
if (val->view->dlv == NULL) {
markanswer(val, "validatezonekey (1)");
return (ISC_R_SUCCESS);
}
return (startfinddlvsep(val, dns_rootname));
}
if (result == DNS_R_PARTIALMATCH ||
result == ISC_R_SUCCESS)
atsep = ISC_TRUE;
while (result == ISC_R_SUCCESS) {
dns_keynode_t *nextnode = NULL;
dstkey = dns_keynode_key(keynode);
if (dstkey == NULL) {
dns_keytable_detachkeynode(
val->keytable,
&keynode);
break;
}
result = verify(val, dstkey, &sigrdata,
sig.keyid);
if (result == ISC_R_SUCCESS) {
dns_keytable_detachkeynode(
val->keytable,
&keynode);
break;
}
result = dns_keytable_findnextkeynode(
val->keytable,
keynode,
&nextnode);
dns_keytable_detachkeynode(val->keytable,
&keynode);
keynode = nextnode;
}
if (result == ISC_R_SUCCESS) {
marksecure(event);
validator_log(val, ISC_LOG_DEBUG(3),
"signed by trusted key; "
"marking as secure");
return (result);
}
}
if (atsep) {
/*
* We have not found a key to verify this DNSKEY
* RRset. As this is a SEP we have to assume that
* the RRset is invalid.
*/
dns_name_format(val->event->name, namebuf,
sizeof(namebuf));
validator_log(val, ISC_LOG_NOTICE,
"unable to find a DNSKEY which verifies "
"the DNSKEY RRset and also matches a "
"trusted key for '%s'",
namebuf);
validator_log(val, ISC_LOG_NOTICE,
"please check the 'trusted-keys' for "
"'%s' in named.conf.", namebuf);
return (DNS_R_NOVALIDKEY);
}
/*
* If this is the root name and there was no trusted key,
* give up, since there's no DS at the root.
*/
if (dns_name_equal(event->name, dns_rootname)) {
if ((val->attributes & VALATTR_TRIEDVERIFY) != 0) {
validator_log(val, ISC_LOG_DEBUG(3),
"root key failed to validate");
return (DNS_R_NOVALIDSIG);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"no trusted root key");
return (DNS_R_NOVALIDDS);
}
}
find_ds:
/*
* Otherwise, try to find the DS record.
*/
result = view_find(val, val->event->name, dns_rdatatype_ds);
if (result == ISC_R_SUCCESS) {
/*
* We have DS records.
*/
val->dsset = &val->frdataset;
if ((DNS_TRUST_PENDING(val->frdataset.trust) ||
DNS_TRUST_ANSWER(val->frdataset.trust)) &&
dns_rdataset_isassociated(&val->fsigrdataset))
{
result = create_validator(val,
val->event->name,
dns_rdatatype_ds,
&val->frdataset,
&val->fsigrdataset,
dsvalidated,
"validatezonekey");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
} else if (DNS_TRUST_PENDING(val->frdataset.trust)) {
/*
* There should never be an unsigned DS.
*/
dns_rdataset_disassociate(&val->frdataset);
validator_log(val, ISC_LOG_DEBUG(2),
"unsigned DS record");
return (DNS_R_NOVALIDSIG);
} else {
result = ISC_R_SUCCESS;
POST(result);
}
} else if (result == ISC_R_NOTFOUND) {
/*
* We don't have the DS. Find it.
*/
result = create_fetch(val, val->event->name,
dns_rdatatype_ds, dsfetched,
"validatezonekey");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
} else if (result == DNS_R_NCACHENXDOMAIN ||
result == DNS_R_NCACHENXRRSET ||
result == DNS_R_EMPTYNAME ||
result == DNS_R_NXDOMAIN ||
result == DNS_R_NXRRSET ||
result == DNS_R_CNAME)
{
/*
* The DS does not exist.
*/
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
validator_log(val, ISC_LOG_DEBUG(2), "no DS record");
return (DNS_R_NOVALIDSIG);
} else if (result == DNS_R_BROKENCHAIN)
return (result);
}
/*
* We have a DS set.
*/
INSIST(val->dsset != NULL);
if (val->dsset->trust < dns_trust_secure) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure,"
" insecure DS");
return (DNS_R_MUSTBESECURE);
}
if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "validatezonekey (2)");
return (ISC_R_SUCCESS);
}
return (startfinddlvsep(val, val->event->name));
}
/*
* Look through the DS record and find the keys that can sign the
* key set and the matching signature. For each such key, attempt
* verification.
*/
supported_algorithm = ISC_FALSE;
/*
* If DNS_DSDIGEST_SHA256 is present we are required to prefer
* it over DNS_DSDIGEST_SHA1. This in practice means that we
* need to ignore DNS_DSDIGEST_SHA1 if a DNS_DSDIGEST_SHA256
* is present.
*/
memset(digest_types, 1, sizeof(digest_types));
for (result = dns_rdataset_first(val->dsset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(val->dsset)) {
dns_rdata_reset(&dsrdata);
dns_rdataset_current(val->dsset, &dsrdata);
result = dns_rdata_tostruct(&dsrdata, &ds, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_resolver_algorithm_supported(val->view->resolver,
val->event->name,
ds.algorithm))
continue;
if (ds.digest_type == DNS_DSDIGEST_SHA256 &&
ds.length == ISC_SHA256_DIGESTLENGTH) {
digest_types[DNS_DSDIGEST_SHA1] = 0;
break;
}
}
for (result = dns_rdataset_first(val->dsset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(val->dsset))
{
dns_rdata_reset(&dsrdata);
dns_rdataset_current(val->dsset, &dsrdata);
result = dns_rdata_tostruct(&dsrdata, &ds, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (!dns_resolver_digest_supported(val->view->resolver,
ds.digest_type))
continue;
if (digest_types[ds.digest_type] == 0)
continue;
if (!dns_resolver_algorithm_supported(val->view->resolver,
val->event->name,
ds.algorithm))
continue;
supported_algorithm = ISC_TRUE;
dns_rdataset_init(&trdataset);
dns_rdataset_clone(val->event->rdataset, &trdataset);
/*
* Find matching DNSKEY from DS.
*/
result = keyfromds(val, &trdataset, &dsrdata, ds.digest_type,
ds.key_tag, ds.algorithm, &keyrdata);
if (result != ISC_R_SUCCESS) {
dns_rdataset_disassociate(&trdataset);
validator_log(val, ISC_LOG_DEBUG(3),
"no DNSKEY matching DS");
continue;
}
/*
* Check that this DNSKEY signed the DNSKEY rrset.
*/
result = checkkey(val, &keyrdata, ds.key_tag, ds.algorithm);
dns_rdataset_disassociate(&trdataset);
if (result == ISC_R_SUCCESS)
break;
validator_log(val, ISC_LOG_DEBUG(3),
"no RRSIG matching DS key");
}
if (result == ISC_R_SUCCESS) {
marksecure(event);
validator_log(val, ISC_LOG_DEBUG(3), "marking as secure (DS)");
return (result);
} else if (result == ISC_R_NOMORE && !supported_algorithm) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"no supported algorithm/digest (DS)");
return (DNS_R_MUSTBESECURE);
}
validator_log(val, ISC_LOG_DEBUG(3),
"no supported algorithm/digest (DS)");
markanswer(val, "validatezonekey (3)");
return (ISC_R_SUCCESS);
} else {
validator_log(val, ISC_LOG_INFO,
"no valid signature found (DS)");
return (DNS_R_NOVALIDSIG);
}
}
/*%
* Starts a positive response validation.
*
* Returns:
* \li ISC_R_SUCCESS Validation completed successfully
* \li DNS_R_WAIT Validation has started but is waiting
* for an event.
* \li Other return codes are possible and all indicate failure.
*/
static isc_result_t
start_positive_validation(dns_validator_t *val) {
/*
* If this is not a key, go straight into validate().
*/
if (val->event->type != dns_rdatatype_dnskey || !isselfsigned(val))
return (validate(val, ISC_FALSE));
return (validatezonekey(val));
}
/*%
* val_rdataset_first and val_rdataset_next provide iteration methods
* that hide whether we are iterating across a message or a negative
* cache rdataset.
*/
static isc_result_t
val_rdataset_first(dns_validator_t *val, dns_name_t **namep,
dns_rdataset_t **rdatasetp)
{
dns_message_t *message = val->event->message;
isc_result_t result;
REQUIRE(rdatasetp != NULL);
REQUIRE(namep != NULL);
if (message == NULL) {
REQUIRE(*rdatasetp != NULL);
REQUIRE(*namep != NULL);
} else {
REQUIRE(*rdatasetp == NULL);
REQUIRE(*namep == NULL);
}
if (message != NULL) {
result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
if (result != ISC_R_SUCCESS)
return (result);
dns_message_currentname(message, DNS_SECTION_AUTHORITY, namep);
*rdatasetp = ISC_LIST_HEAD((*namep)->list);
INSIST(*rdatasetp != NULL);
} else {
result = dns_rdataset_first(val->event->rdataset);
if (result == ISC_R_SUCCESS)
dns_ncache_current(val->event->rdataset, *namep,
*rdatasetp);
}
return (result);
}
static isc_result_t
val_rdataset_next(dns_validator_t *val, dns_name_t **namep,
dns_rdataset_t **rdatasetp)
{
dns_message_t *message = val->event->message;
isc_result_t result = ISC_R_SUCCESS;
REQUIRE(rdatasetp != NULL && *rdatasetp != NULL);
REQUIRE(namep != NULL && *namep != NULL);
if (message != NULL) {
dns_rdataset_t *rdataset = *rdatasetp;
rdataset = ISC_LIST_NEXT(rdataset, link);
if (rdataset == NULL) {
*namep = NULL;
result = dns_message_nextname(message,
DNS_SECTION_AUTHORITY);
if (result == ISC_R_SUCCESS) {
dns_message_currentname(message,
DNS_SECTION_AUTHORITY,
namep);
rdataset = ISC_LIST_HEAD((*namep)->list);
INSIST(rdataset != NULL);
}
}
*rdatasetp = rdataset;
} else {
dns_rdataset_disassociate(*rdatasetp);
result = dns_rdataset_next(val->event->rdataset);
if (result == ISC_R_SUCCESS)
dns_ncache_current(val->event->rdataset, *namep,
*rdatasetp);
}
return (result);
}
/*%
* Look for NODATA at the wildcard and NOWILDCARD proofs in the
* previously validated NSEC records. As these proofs are mutually
* exclusive we stop when one is found.
*
* Returns
* \li ISC_R_SUCCESS
*/
static isc_result_t
checkwildcard(dns_validator_t *val, dns_rdatatype_t type, dns_name_t *zonename)
{
dns_name_t *name, *wild, tname;
isc_result_t result;
isc_boolean_t exists, data;
char namebuf[DNS_NAME_FORMATSIZE];
dns_rdataset_t *rdataset, trdataset;
dns_name_init(&tname, NULL);
dns_rdataset_init(&trdataset);
wild = dns_fixedname_name(&val->wild);
if (dns_name_countlabels(wild) == 0) {
validator_log(val, ISC_LOG_DEBUG(3),
"in checkwildcard: no wildcard to check");
return (ISC_R_SUCCESS);
}
dns_name_format(wild, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3), "in checkwildcard: %s", namebuf);
if (val->event->message == NULL) {
name = &tname;
rdataset = &trdataset;
} else {
name = NULL;
rdataset = NULL;
}
for (result = val_rdataset_first(val, &name, &rdataset);
result == ISC_R_SUCCESS;
result = val_rdataset_next(val, &name, &rdataset))
{
if (rdataset->type != type ||
rdataset->trust != dns_trust_secure)
continue;
if (rdataset->type == dns_rdatatype_nsec &&
(NEEDNODATA(val) || NEEDNOWILDCARD(val)) &&
!FOUNDNODATA(val) && !FOUNDNOWILDCARD(val) &&
nsecnoexistnodata(val, wild, name, rdataset,
&exists, &data, NULL)
== ISC_R_SUCCESS)
{
dns_name_t **proofs = val->event->proofs;
if (exists && !data)
val->attributes |= VALATTR_FOUNDNODATA;
if (exists && !data && NEEDNODATA(val))
proofs[DNS_VALIDATOR_NODATAPROOF] =
name;
if (!exists)
val->attributes |=
VALATTR_FOUNDNOWILDCARD;
if (!exists && NEEDNOQNAME(val))
proofs[DNS_VALIDATOR_NOWILDCARDPROOF] =
name;
if (dns_rdataset_isassociated(&trdataset))
dns_rdataset_disassociate(&trdataset);
return (ISC_R_SUCCESS);
}
if (rdataset->type == dns_rdatatype_nsec3 &&
(NEEDNODATA(val) || NEEDNOWILDCARD(val)) &&
!FOUNDNODATA(val) && !FOUNDNOWILDCARD(val) &&
nsec3noexistnodata(val, wild, name, rdataset,
zonename, &exists, &data,
NULL, NULL, NULL, NULL, NULL,
NULL) == ISC_R_SUCCESS)
{
dns_name_t **proofs = val->event->proofs;
if (exists && !data)
val->attributes |= VALATTR_FOUNDNODATA;
if (exists && !data && NEEDNODATA(val))
proofs[DNS_VALIDATOR_NODATAPROOF] =
name;
if (!exists)
val->attributes |=
VALATTR_FOUNDNOWILDCARD;
if (!exists && NEEDNOQNAME(val))
proofs[DNS_VALIDATOR_NOWILDCARDPROOF] =
name;
if (dns_rdataset_isassociated(&trdataset))
dns_rdataset_disassociate(&trdataset);
return (ISC_R_SUCCESS);
}
}
if (result == ISC_R_NOMORE)
result = ISC_R_SUCCESS;
if (dns_rdataset_isassociated(&trdataset))
dns_rdataset_disassociate(&trdataset);
return (result);
}
static isc_result_t
findnsec3proofs(dns_validator_t *val) {
dns_name_t *name, tname;
isc_result_t result;
isc_boolean_t exists, data, optout, unknown;
isc_boolean_t setclosest, setnearest;
dns_fixedname_t fclosest, fnearest, fzonename;
dns_name_t *closest, *nearest, *zonename;
dns_name_t **proofs = val->event->proofs;
dns_rdataset_t *rdataset, trdataset;
dns_name_init(&tname, NULL);
dns_rdataset_init(&trdataset);
dns_fixedname_init(&fclosest);
dns_fixedname_init(&fnearest);
dns_fixedname_init(&fzonename);
closest = dns_fixedname_name(&fclosest);
nearest = dns_fixedname_name(&fnearest);
zonename = dns_fixedname_name(&fzonename);
if (val->event->message == NULL) {
name = &tname;
rdataset = &trdataset;
} else {
name = NULL;
rdataset = NULL;
}
for (result = val_rdataset_first(val, &name, &rdataset);
result == ISC_R_SUCCESS;
result = val_rdataset_next(val, &name, &rdataset))
{
if (rdataset->type != dns_rdatatype_nsec3 ||
rdataset->trust != dns_trust_secure)
continue;
result = nsec3noexistnodata(val, val->event->name,
name, rdataset,
zonename, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL);
if (result != ISC_R_IGNORE && result != ISC_R_SUCCESS) {
if (dns_rdataset_isassociated(&trdataset))
dns_rdataset_disassociate(&trdataset);
return (result);
}
}
if (result != ISC_R_NOMORE)
result = ISC_R_SUCCESS;
POST(result);
if (dns_name_countlabels(zonename) == 0)
return (ISC_R_SUCCESS);
for (result = val_rdataset_first(val, &name, &rdataset);
result == ISC_R_SUCCESS;
result = val_rdataset_next(val, &name, &rdataset))
{
if (rdataset->type != dns_rdatatype_nsec3 ||
rdataset->trust != dns_trust_secure)
continue;
/*
* We process all NSEC3 records to find the closest
* encloser and nearest name to the closest encloser.
*/
setclosest = setnearest = ISC_FALSE;
optout = ISC_FALSE;
unknown = ISC_FALSE;
(void)nsec3noexistnodata(val, val->event->name, name, rdataset,
zonename, &exists, &data, &optout,
&unknown, &setclosest, &setnearest,
closest, nearest);
if (setclosest)
proofs[DNS_VALIDATOR_CLOSESTENCLOSER] = name;
if (unknown)
val->attributes |= VALATTR_FOUNDUNKNOWN;
if (result != ISC_R_SUCCESS)
continue;
if (exists && !data && NEEDNODATA(val)) {
val->attributes |= VALATTR_FOUNDNODATA;
proofs[DNS_VALIDATOR_NODATAPROOF] = name;
}
if (!exists && setnearest) {
val->attributes |= VALATTR_FOUNDNOQNAME;
proofs[DNS_VALIDATOR_NOQNAMEPROOF] = name;
if (optout)
val->attributes |= VALATTR_FOUNDOPTOUT;
}
}
if (result == ISC_R_NOMORE)
result = ISC_R_SUCCESS;
/*
* To know we have a valid noqname and optout proofs we need to also
* have a valid closest encloser. Otherwise we could still be looking
* at proofs from the parent zone.
*/
if (dns_name_countlabels(closest) > 0 &&
dns_name_countlabels(nearest) ==
dns_name_countlabels(closest) + 1 &&
dns_name_issubdomain(nearest, closest))
{
val->attributes |= VALATTR_FOUNDCLOSEST;
result = dns_name_concatenate(dns_wildcardname, closest,
dns_fixedname_name(&val->wild),
NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
} else {
val->attributes &= ~VALATTR_FOUNDNOQNAME;
val->attributes &= ~VALATTR_FOUNDOPTOUT;
proofs[DNS_VALIDATOR_NOQNAMEPROOF] = NULL;
}
/*
* Do we need to check for the wildcard?
*/
if (FOUNDNOQNAME(val) && FOUNDCLOSEST(val) &&
((NEEDNODATA(val) && !FOUNDNODATA(val)) || NEEDNOWILDCARD(val))) {
result = checkwildcard(val, dns_rdatatype_nsec3, zonename);
if (result != ISC_R_SUCCESS)
return (result);
}
return (result);
}
/*%
* Validate the authority section records.
*/
static isc_result_t
validate_authority(dns_validator_t *val, isc_boolean_t resume) {
dns_name_t *name;
dns_message_t *message = val->event->message;
isc_result_t result;
if (!resume)
result = dns_message_firstname(message, DNS_SECTION_AUTHORITY);
else
result = ISC_R_SUCCESS;
for (;
result == ISC_R_SUCCESS;
result = dns_message_nextname(message, DNS_SECTION_AUTHORITY))
{
dns_rdataset_t *rdataset = NULL, *sigrdataset = NULL;
name = NULL;
dns_message_currentname(message, DNS_SECTION_AUTHORITY, &name);
if (resume) {
rdataset = ISC_LIST_NEXT(val->currentset, link);
val->currentset = NULL;
resume = ISC_FALSE;
} else
rdataset = ISC_LIST_HEAD(name->list);
for (;
rdataset != NULL;
rdataset = ISC_LIST_NEXT(rdataset, link))
{
if (rdataset->type == dns_rdatatype_rrsig)
continue;
for (sigrdataset = ISC_LIST_HEAD(name->list);
sigrdataset != NULL;
sigrdataset = ISC_LIST_NEXT(sigrdataset,
link))
{
if (sigrdataset->type == dns_rdatatype_rrsig &&
sigrdataset->covers == rdataset->type)
break;
}
/*
* If a signed zone is missing the zone key, bad
* things could happen. A query for data in the zone
* would lead to a query for the zone key, which
* would return a negative answer, which would contain
* an SOA and an NSEC signed by the missing key, which
* would trigger another query for the DNSKEY (since
* the first one is still in progress), and go into an
* infinite loop. Avoid that.
*/
if (val->event->type == dns_rdatatype_dnskey &&
rdataset->type == dns_rdatatype_nsec &&
dns_name_equal(name, val->event->name))
{
dns_rdata_t nsec = DNS_RDATA_INIT;
result = dns_rdataset_first(rdataset);
if (result != ISC_R_SUCCESS)
return (result);
dns_rdataset_current(rdataset, &nsec);
if (dns_nsec_typepresent(&nsec,
dns_rdatatype_soa))
continue;
}
val->currentset = rdataset;
result = create_validator(val, name, rdataset->type,
rdataset, sigrdataset,
authvalidated,
"validate_authority");
if (result != ISC_R_SUCCESS)
return (result);
val->authcount++;
return (DNS_R_WAIT);
}
}
if (result == ISC_R_NOMORE)
result = ISC_R_SUCCESS;
return (result);
}
/*%
* Validate the ncache elements.
*/
static isc_result_t
validate_ncache(dns_validator_t *val, isc_boolean_t resume) {
dns_name_t *name;
isc_result_t result;
if (!resume)
result = dns_rdataset_first(val->event->rdataset);
else
result = dns_rdataset_next(val->event->rdataset);
for (;
result == ISC_R_SUCCESS;
result = dns_rdataset_next(val->event->rdataset))
{
dns_rdataset_t *rdataset, *sigrdataset = NULL;
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
dns_fixedname_init(&val->fname);
name = dns_fixedname_name(&val->fname);
rdataset = &val->frdataset;
dns_ncache_current(val->event->rdataset, name, rdataset);
if (val->frdataset.type == dns_rdatatype_rrsig)
continue;
result = dns_ncache_getsigrdataset(val->event->rdataset, name,
rdataset->type,
&val->fsigrdataset);
if (result == ISC_R_SUCCESS)
sigrdataset = &val->fsigrdataset;
/*
* If a signed zone is missing the zone key, bad
* things could happen. A query for data in the zone
* would lead to a query for the zone key, which
* would return a negative answer, which would contain
* an SOA and an NSEC signed by the missing key, which
* would trigger another query for the DNSKEY (since
* the first one is still in progress), and go into an
* infinite loop. Avoid that.
*/
if (val->event->type == dns_rdatatype_dnskey &&
rdataset->type == dns_rdatatype_nsec &&
dns_name_equal(name, val->event->name))
{
dns_rdata_t nsec = DNS_RDATA_INIT;
result = dns_rdataset_first(rdataset);
if (result != ISC_R_SUCCESS)
return (result);
dns_rdataset_current(rdataset, &nsec);
if (dns_nsec_typepresent(&nsec,
dns_rdatatype_soa))
continue;
}
val->currentset = rdataset;
result = create_validator(val, name, rdataset->type,
rdataset, sigrdataset,
authvalidated,
"validate_ncache");
if (result != ISC_R_SUCCESS)
return (result);
val->authcount++;
return (DNS_R_WAIT);
}
if (result == ISC_R_NOMORE)
result = ISC_R_SUCCESS;
return (result);
}
/*%
* Prove a negative answer is good or that there is a NOQNAME when the
* answer is from a wildcard.
*
* Loop through the authority section looking for NODATA, NOWILDCARD
* and NOQNAME proofs in the NSEC records by calling authvalidated().
*
* If the required proofs are found we are done.
*
* If the proofs are not found attempt to prove this is a unsecure
* response.
*/
static isc_result_t
nsecvalidate(dns_validator_t *val, isc_boolean_t resume) {
isc_result_t result;
if (resume)
validator_log(val, ISC_LOG_DEBUG(3), "resuming nsecvalidate");
if (val->event->message == NULL)
result = validate_ncache(val, resume);
else
result = validate_authority(val, resume);
if (result != ISC_R_SUCCESS)
return (result);
/*
* Do we only need to check for NOQNAME? To get here we must have
* had a secure wildcard answer.
*/
if (!NEEDNODATA(val) && !NEEDNOWILDCARD(val) && NEEDNOQNAME(val)) {
if (!FOUNDNOQNAME(val))
findnsec3proofs(val);
if (FOUNDNOQNAME(val) && FOUNDCLOSEST(val)) {
validator_log(val, ISC_LOG_DEBUG(3),
"marking as secure, noqname proof found");
marksecure(val->event);
return (ISC_R_SUCCESS);
} else if (FOUNDOPTOUT(val) &&
dns_name_countlabels(dns_fixedname_name(&val->wild))
!= 0) {
validator_log(val, ISC_LOG_DEBUG(3),
"optout proof found");
val->event->optout = ISC_TRUE;
markanswer(val, "nsecvalidate (1)");
return (ISC_R_SUCCESS);
} else if ((val->attributes & VALATTR_FOUNDUNKNOWN) != 0) {
validator_log(val, ISC_LOG_DEBUG(3),
"unknown NSEC3 hash algorithm found");
markanswer(val, "nsecvalidate (2)");
return (ISC_R_SUCCESS);
}
validator_log(val, ISC_LOG_DEBUG(3),
"noqname proof not found");
return (DNS_R_NOVALIDNSEC);
}
if (!FOUNDNOQNAME(val) && !FOUNDNODATA(val))
findnsec3proofs(val);
/*
* Do we need to check for the wildcard?
*/
if (FOUNDNOQNAME(val) && FOUNDCLOSEST(val) &&
((NEEDNODATA(val) && !FOUNDNODATA(val)) || NEEDNOWILDCARD(val))) {
result = checkwildcard(val, dns_rdatatype_nsec, NULL);
if (result != ISC_R_SUCCESS)
return (result);
}
if ((NEEDNODATA(val) && (FOUNDNODATA(val) || FOUNDOPTOUT(val))) ||
(NEEDNOQNAME(val) && FOUNDNOQNAME(val) &&
NEEDNOWILDCARD(val) && FOUNDNOWILDCARD(val) &&
FOUNDCLOSEST(val))) {
if ((val->attributes & VALATTR_FOUNDOPTOUT) != 0)
val->event->optout = ISC_TRUE;
validator_log(val, ISC_LOG_DEBUG(3),
"nonexistence proof(s) found");
if (val->event->message == NULL)
marksecure(val->event);
return (ISC_R_SUCCESS);
}
if (val->authfail != 0 && val->authcount == val->authfail)
return (DNS_R_BROKENCHAIN);
validator_log(val, ISC_LOG_DEBUG(3),
"nonexistence proof(s) not found");
val->attributes |= VALATTR_INSECURITY;
return (proveunsecure(val, ISC_FALSE, ISC_FALSE));
}
static isc_boolean_t
check_ds(dns_validator_t *val, dns_name_t *name, dns_rdataset_t *rdataset) {
dns_rdata_t dsrdata = DNS_RDATA_INIT;
dns_rdata_ds_t ds;
isc_result_t result;
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset)) {
dns_rdataset_current(rdataset, &dsrdata);
result = dns_rdata_tostruct(&dsrdata, &ds, NULL);
RUNTIME_CHECK(result == ISC_R_SUCCESS);
if (dns_resolver_digest_supported(val->view->resolver,
ds.digest_type) &&
dns_resolver_algorithm_supported(val->view->resolver,
name, ds.algorithm)) {
dns_rdata_reset(&dsrdata);
return (ISC_TRUE);
}
dns_rdata_reset(&dsrdata);
}
return (ISC_FALSE);
}
static void
dlvvalidated(isc_task_t *task, isc_event_t *event) {
dns_validatorevent_t *devent;
dns_validator_t *val;
isc_result_t eresult;
isc_boolean_t want_destroy;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_VALIDATORDONE);
devent = (dns_validatorevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
isc_event_free(&event);
dns_validator_destroy(&val->subvalidator);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in dlvvalidated");
LOCK(&val->lock);
if (CANCELED(val)) {
validator_done(val, ISC_R_CANCELED);
} else if (eresult == ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3),
"dlvset with trust %s",
dns_trust_totext(val->frdataset.trust));
dns_rdataset_clone(&val->frdataset, &val->dlv);
val->havedlvsep = ISC_TRUE;
if (dlv_algorithm_supported(val))
dlv_validator_start(val);
else {
markanswer(val, "dlvvalidated");
validator_done(val, ISC_R_SUCCESS);
}
} else {
if (eresult != DNS_R_BROKENCHAIN) {
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_expire(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_expire(&val->fsigrdataset);
}
validator_log(val, ISC_LOG_DEBUG(3),
"dlvvalidated: got %s",
isc_result_totext(eresult));
validator_done(val, DNS_R_BROKENCHAIN);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Callback from fetching a DLV record.
*
* Resumes the DLV lookup process.
*/
static void
dlvfetched(isc_task_t *task, isc_event_t *event) {
char namebuf[DNS_NAME_FORMATSIZE];
dns_fetchevent_t *devent;
dns_validator_t *val;
isc_boolean_t want_destroy;
isc_result_t eresult;
isc_result_t result;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_FETCHDONE);
devent = (dns_fetchevent_t *)event;
val = devent->ev_arg;
eresult = devent->result;
/* Free resources which are not of interest. */
if (devent->node != NULL)
dns_db_detachnode(devent->db, &devent->node);
if (devent->db != NULL)
dns_db_detach(&devent->db);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
isc_event_free(&event);
dns_resolver_destroyfetch(&val->fetch);
INSIST(val->event != NULL);
validator_log(val, ISC_LOG_DEBUG(3), "in dlvfetched: %s",
dns_result_totext(eresult));
LOCK(&val->lock);
if (eresult == ISC_R_SUCCESS) {
dns_name_format(dns_fixedname_name(&val->dlvsep), namebuf,
sizeof(namebuf));
dns_rdataset_clone(&val->frdataset, &val->dlv);
val->havedlvsep = ISC_TRUE;
if (dlv_algorithm_supported(val)) {
validator_log(val, ISC_LOG_DEBUG(3), "DLV %s found",
namebuf);
dlv_validator_start(val);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"DLV %s found with no supported algorithms",
namebuf);
markanswer(val, "dlvfetched (1)");
validator_done(val, ISC_R_SUCCESS);
}
} else if (eresult == DNS_R_NXRRSET ||
eresult == DNS_R_NXDOMAIN ||
eresult == DNS_R_NCACHENXRRSET ||
eresult == DNS_R_NCACHENXDOMAIN) {
result = finddlvsep(val, ISC_TRUE);
if (result == ISC_R_SUCCESS) {
if (dlv_algorithm_supported(val)) {
dns_name_format(dns_fixedname_name(&val->dlvsep),
namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3),
"DLV %s found", namebuf);
dlv_validator_start(val);
} else {
validator_log(val, ISC_LOG_DEBUG(3),
"DLV %s found with no supported "
"algorithms", namebuf);
markanswer(val, "dlvfetched (2)");
validator_done(val, ISC_R_SUCCESS);
}
} else if (result == ISC_R_NOTFOUND) {
validator_log(val, ISC_LOG_DEBUG(3), "DLV not found");
markanswer(val, "dlvfetched (3)");
validator_done(val, ISC_R_SUCCESS);
} else {
validator_log(val, ISC_LOG_DEBUG(3), "DLV lookup: %s",
dns_result_totext(result));
if (result != DNS_R_WAIT)
validator_done(val, result);
}
} else {
validator_log(val, ISC_LOG_DEBUG(3), "DLV lookup: %s",
dns_result_totext(eresult));
validator_done(val, eresult);
}
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
/*%
* Start the DLV lookup process.
*
* Returns
* \li ISC_R_SUCCESS
* \li DNS_R_WAIT
* \li Others on validation failures.
*/
static isc_result_t
startfinddlvsep(dns_validator_t *val, dns_name_t *unsecure) {
char namebuf[DNS_NAME_FORMATSIZE];
isc_result_t result;
INSIST(!DLVTRIED(val));
val->attributes |= VALATTR_DLVTRIED;
dns_name_format(unsecure, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3),
"plain DNSSEC returns unsecure (%s): looking for DLV",
namebuf);
if (dns_name_issubdomain(val->event->name, val->view->dlv)) {
validator_log(val, ISC_LOG_WARNING, "must be secure failure, "
" %s is under DLV (startfinddlvsep)", namebuf);
return (DNS_R_MUSTBESECURE);
}
val->dlvlabels = dns_name_countlabels(unsecure) - 1;
result = finddlvsep(val, ISC_FALSE);
if (result == ISC_R_NOTFOUND) {
validator_log(val, ISC_LOG_DEBUG(3), "DLV not found");
markanswer(val, "startfinddlvsep (1)");
return (ISC_R_SUCCESS);
}
if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(3), "DLV lookup: %s",
dns_result_totext(result));
return (result);
}
dns_name_format(dns_fixedname_name(&val->dlvsep), namebuf,
sizeof(namebuf));
if (dlv_algorithm_supported(val)) {
validator_log(val, ISC_LOG_DEBUG(3), "DLV %s found", namebuf);
dlv_validator_start(val);
return (DNS_R_WAIT);
}
validator_log(val, ISC_LOG_DEBUG(3), "DLV %s found with no supported "
"algorithms", namebuf);
markanswer(val, "startfinddlvsep (2)");
validator_done(val, ISC_R_SUCCESS);
return (ISC_R_SUCCESS);
}
/*%
* Continue the DLV lookup process.
*
* Returns
* \li ISC_R_SUCCESS
* \li ISC_R_NOTFOUND
* \li DNS_R_WAIT
* \li Others on validation failure.
*/
static isc_result_t
finddlvsep(dns_validator_t *val, isc_boolean_t resume) {
char namebuf[DNS_NAME_FORMATSIZE];
dns_fixedname_t dlvfixed;
dns_name_t *dlvname;
dns_name_t *dlvsep;
dns_name_t noroot;
isc_result_t result;
unsigned int labels;
INSIST(val->view->dlv != NULL);
if (!resume) {
if (dns_name_issubdomain(val->event->name, val->view->dlv)) {
dns_name_format(val->event->name, namebuf,
sizeof(namebuf));
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"%s is under DLV (finddlvsep)", namebuf);
return (DNS_R_MUSTBESECURE);
}
dns_fixedname_init(&val->dlvsep);
dlvsep = dns_fixedname_name(&val->dlvsep);
dns_name_copy(val->event->name, dlvsep, NULL);
/*
* If this is a response to a DS query, we need to look in
* the parent zone for the trust anchor.
*/
if (val->event->type == dns_rdatatype_ds) {
labels = dns_name_countlabels(dlvsep);
if (labels == 0)
return (ISC_R_NOTFOUND);
dns_name_getlabelsequence(dlvsep, 1, labels - 1,
dlvsep);
}
} else {
dlvsep = dns_fixedname_name(&val->dlvsep);
labels = dns_name_countlabels(dlvsep);
dns_name_getlabelsequence(dlvsep, 1, labels - 1, dlvsep);
}
dns_name_init(&noroot, NULL);
dns_fixedname_init(&dlvfixed);
dlvname = dns_fixedname_name(&dlvfixed);
labels = dns_name_countlabels(dlvsep);
if (labels == 0)
return (ISC_R_NOTFOUND);
dns_name_getlabelsequence(dlvsep, 0, labels - 1, &noroot);
result = dns_name_concatenate(&noroot, val->view->dlv, dlvname, NULL);
while (result == ISC_R_NOSPACE) {
labels = dns_name_countlabels(dlvsep);
dns_name_getlabelsequence(dlvsep, 1, labels - 1, dlvsep);
dns_name_getlabelsequence(dlvsep, 0, labels - 2, &noroot);
result = dns_name_concatenate(&noroot, val->view->dlv,
dlvname, NULL);
}
if (result != ISC_R_SUCCESS) {
validator_log(val, ISC_LOG_DEBUG(2), "DLV concatenate failed");
return (DNS_R_NOVALIDSIG);
}
while (dns_name_countlabels(dlvname) >=
dns_name_countlabels(val->view->dlv) + val->dlvlabels) {
dns_name_format(dlvname, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3), "looking for DLV %s",
namebuf);
result = view_find(val, dlvname, dns_rdatatype_dlv);
if (result == ISC_R_SUCCESS) {
if (DNS_TRUST_PENDING(val->frdataset.trust) &&
dns_rdataset_isassociated(&val->fsigrdataset))
{
dns_fixedname_init(&val->fname);
dns_name_copy(dlvname,
dns_fixedname_name(&val->fname),
NULL);
result = create_validator(val,
dns_fixedname_name(&val->fname),
dns_rdatatype_dlv,
&val->frdataset,
&val->fsigrdataset,
dlvvalidated,
"finddlvsep");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
}
if (val->frdataset.trust < dns_trust_secure) {
validator_log(val, ISC_LOG_DEBUG(3),
"DLV not validated");
return (DNS_R_NOVALIDSIG);
}
val->havedlvsep = ISC_TRUE;
dns_rdataset_clone(&val->frdataset, &val->dlv);
return (ISC_R_SUCCESS);
}
if (result == ISC_R_NOTFOUND) {
result = create_fetch(val, dlvname, dns_rdatatype_dlv,
dlvfetched, "finddlvsep");
if (result != ISC_R_SUCCESS)
return (result);
return (DNS_R_WAIT);
}
if (result != DNS_R_NXRRSET &&
result != DNS_R_NXDOMAIN &&
result != DNS_R_EMPTYNAME &&
result != DNS_R_NCACHENXRRSET &&
result != DNS_R_NCACHENXDOMAIN)
return (result);
/*
* Strip first labels from both dlvsep and dlvname.
*/
labels = dns_name_countlabels(dlvsep);
if (labels == 0)
break;
dns_name_getlabelsequence(dlvsep, 1, labels - 1, dlvsep);
labels = dns_name_countlabels(dlvname);
dns_name_getlabelsequence(dlvname, 1, labels - 1, dlvname);
}
return (ISC_R_NOTFOUND);
}
/*%
* proveunsecure walks down from the SEP looking for a break in the
* chain of trust. That occurs when we can prove the DS record does
* not exist at a delegation point or the DS exists at a delegation
* but we don't support the algorithm/digest.
*
* If DLV is active and we look for a DLV record at or below the
* point we go insecure. If found we restart the validation process.
* If not found or DLV isn't active we mark the response as a answer.
*
* Returns:
* \li ISC_R_SUCCESS val->event->name is in a unsecure zone
* \li DNS_R_WAIT validation is in progress.
* \li DNS_R_MUSTBESECURE val->event->name is supposed to be secure
* (policy) but we proved that it is unsecure.
* \li DNS_R_NOVALIDSIG
* \li DNS_R_NOVALIDNSEC
* \li DNS_R_NOTINSECURE
* \li DNS_R_BROKENCHAIN
*/
static isc_result_t
proveunsecure(dns_validator_t *val, isc_boolean_t have_ds, isc_boolean_t resume)
{
isc_result_t result;
dns_fixedname_t fixedsecroot;
dns_name_t *secroot;
dns_name_t *tname;
char namebuf[DNS_NAME_FORMATSIZE];
dns_name_t *found;
dns_fixedname_t fixedfound;
dns_fixedname_init(&fixedsecroot);
secroot = dns_fixedname_name(&fixedsecroot);
dns_fixedname_init(&fixedfound);
found = dns_fixedname_name(&fixedfound);
if (val->havedlvsep)
dns_name_copy(dns_fixedname_name(&val->dlvsep), secroot, NULL);
else {
unsigned int labels;
dns_name_copy(val->event->name, secroot, NULL);
/*
* If this is a response to a DS query, we need to look in
* the parent zone for the trust anchor.
*/
labels = dns_name_countlabels(secroot);
if (val->event->type == dns_rdatatype_ds && labels > 1U)
dns_name_getlabelsequence(secroot, 1, labels - 1,
secroot);
result = dns_keytable_finddeepestmatch(val->keytable,
secroot, secroot);
if (result == ISC_R_NOTFOUND) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"not beneath secure root");
result = DNS_R_MUSTBESECURE;
goto out;
} else
validator_log(val, ISC_LOG_DEBUG(3),
"not beneath secure root");
if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "proveunsecure (1)");
return (ISC_R_SUCCESS);
}
return (startfinddlvsep(val, dns_rootname));
} else if (result != ISC_R_SUCCESS)
return (result);
}
if (!resume) {
/*
* We are looking for breaks below the SEP so add a label.
*/
val->labels = dns_name_countlabels(secroot) + 1;
} else {
validator_log(val, ISC_LOG_DEBUG(3), "resuming proveunsecure");
/*
* If we have a DS rdataset and it is secure then check if
* the DS rdataset has a supported algorithm combination.
* If not this is an insecure delegation as far as this
* resolver is concerned. Fall back to DLV if available.
*/
if (have_ds && val->frdataset.trust >= dns_trust_secure &&
!check_ds(val, dns_fixedname_name(&val->fname),
&val->frdataset)) {
dns_name_format(dns_fixedname_name(&val->fname),
namebuf, sizeof(namebuf));
if ((val->view->dlv == NULL || DLVTRIED(val)) &&
val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure at '%s', "
"can't fall back to DLV",
namebuf);
result = DNS_R_MUSTBESECURE;
goto out;
}
validator_log(val, ISC_LOG_DEBUG(3),
"no supported algorithm/digest (%s/DS)",
namebuf);
if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "proveunsecure (2)");
result = ISC_R_SUCCESS;
goto out;
}
result = startfinddlvsep(val,
dns_fixedname_name(&val->fname));
goto out;
}
val->labels++;
}
for (;
val->labels <= dns_name_countlabels(val->event->name);
val->labels++)
{
dns_fixedname_init(&val->fname);
tname = dns_fixedname_name(&val->fname);
if (val->labels == dns_name_countlabels(val->event->name))
dns_name_copy(val->event->name, tname, NULL);
else
dns_name_split(val->event->name, val->labels,
NULL, tname);
dns_name_format(tname, namebuf, sizeof(namebuf));
validator_log(val, ISC_LOG_DEBUG(3),
"checking existence of DS at '%s'",
namebuf);
result = view_find(val, tname, dns_rdatatype_ds);
if (result == DNS_R_NXRRSET || result == DNS_R_NCACHENXRRSET) {
/*
* There is no DS. If this is a delegation,
* we may be done.
*/
/*
* If we have "trust == answer" then this namespace
* has switched from insecure to should be secure.
*/
if (DNS_TRUST_PENDING(val->frdataset.trust) ||
DNS_TRUST_ANSWER(val->frdataset.trust)) {
result = create_validator(val, tname,
dns_rdatatype_ds,
&val->frdataset,
NULL, dsvalidated,
"proveunsecure");
if (result != ISC_R_SUCCESS)
goto out;
return (DNS_R_WAIT);
}
/*
* Zones using NSEC3 don't return a NSEC RRset so
* we need to use dns_view_findzonecut2 to find
* the zone cut.
*/
if (result == DNS_R_NXRRSET &&
!dns_rdataset_isassociated(&val->frdataset) &&
dns_view_findzonecut2(val->view, tname, found,
0, 0, ISC_FALSE, ISC_FALSE,
NULL, NULL) == ISC_R_SUCCESS &&
dns_name_equal(tname, found)) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"no DS at zone cut");
return (DNS_R_MUSTBESECURE);
}
if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "proveunsecure (3)");
return (ISC_R_SUCCESS);
}
return (startfinddlvsep(val, tname));
}
if (val->frdataset.trust < dns_trust_secure) {
/*
* This shouldn't happen, since the negative
* response should have been validated. Since
* there's no way of validating existing
* negative response blobs, give up.
*/
validator_log(val, ISC_LOG_WARNING,
"can't validate existing "
"negative responses (no DS)");
result = DNS_R_NOVALIDSIG;
goto out;
}
if (isdelegation(tname, &val->frdataset, result)) {
if (val->mustbesecure) {
validator_log(val, ISC_LOG_WARNING,
"must be secure failure, "
"%s is a delegation",
namebuf);
return (DNS_R_MUSTBESECURE);
}
if (val->view->dlv == NULL || DLVTRIED(val)) {
markanswer(val, "proveunsecure (4)");
return (ISC_R_SUCCESS);
}
return (startfinddlvsep(val, tname));
}
continue;
} else if (result == DNS_R_CNAME) {
if (DNS_TRUST_PENDING(val->frdataset.trust) ||
DNS_TRUST_ANSWER(val->frdataset.trust)) {
result = create_validator(val, tname,
dns_rdatatype_cname,
&val->frdataset,
NULL, cnamevalidated,
"proveunsecure "
"(cname)");
if (result != ISC_R_SUCCESS)
goto out;
return (DNS_R_WAIT);
}
continue;
} else if (result == ISC_R_SUCCESS) {
/*
* There is a DS here. Verify that it's secure and
* continue.
*/
if (val->frdataset.trust >= dns_trust_secure) {
if (!check_ds(val, tname, &val->frdataset)) {
validator_log(val, ISC_LOG_DEBUG(3),
"no supported algorithm/"
"digest (%s/DS)", namebuf);
if (val->mustbesecure) {
validator_log(val,
ISC_LOG_WARNING,
"must be secure failure, "
"no supported algorithm/"
"digest (%s/DS)",
namebuf);
result = DNS_R_MUSTBESECURE;
goto out;
}
if (val->view->dlv == NULL ||
DLVTRIED(val)) {
markanswer(val,
"proveunsecure (5)");
result = ISC_R_SUCCESS;
goto out;
}
result = startfinddlvsep(val, tname);
goto out;
}
continue;
}
else if (!dns_rdataset_isassociated(&val->fsigrdataset))
{
validator_log(val, ISC_LOG_DEBUG(3),
"DS is unsigned");
result = DNS_R_NOVALIDSIG;
goto out;
}
/*
* Validate / re-validate answer.
*/
result = create_validator(val, tname, dns_rdatatype_ds,
&val->frdataset,
&val->fsigrdataset,
dsvalidated,
"proveunsecure");
if (result != ISC_R_SUCCESS)
goto out;
return (DNS_R_WAIT);
} else if (result == DNS_R_NXDOMAIN ||
result == DNS_R_NCACHENXDOMAIN) {
/*
* This is not a zone cut. Assuming things are
* as expected, continue.
*/
if (!dns_rdataset_isassociated(&val->frdataset)) {
/*
* There should be an NSEC here, since we
* are still in a secure zone.
*/
result = DNS_R_NOVALIDNSEC;
goto out;
} else if (DNS_TRUST_PENDING(val->frdataset.trust) ||
DNS_TRUST_ANSWER(val->frdataset.trust)) {
/*
* If we have "trust == answer" then this namespace
* has switched from insecure to should be secure.
*/
result = create_validator(val, tname,
dns_rdatatype_ds,
&val->frdataset,
NULL, dsvalidated,
"proveunsecure");
if (result != ISC_R_SUCCESS)
goto out;
return (DNS_R_WAIT);
} else if (val->frdataset.trust < dns_trust_secure) {
/*
* This shouldn't happen, since the negative
* response should have been validated. Since
* there's no way of validating existing
* negative response blobs, give up.
*/
validator_log(val, ISC_LOG_WARNING,
"can't validate existing "
"negative responses "
"(not a zone cut)");
result = DNS_R_NOVALIDSIG;
goto out;
}
continue;
} else if (result == ISC_R_NOTFOUND) {
/*
* We don't know anything about the DS. Find it.
*/
result = create_fetch(val, tname, dns_rdatatype_ds,
dsfetched2, "proveunsecure");
if (result != ISC_R_SUCCESS)
goto out;
return (DNS_R_WAIT);
} else if (result == DNS_R_BROKENCHAIN)
return (result);
}
/* Couldn't complete insecurity proof */
validator_log(val, ISC_LOG_DEBUG(3), "insecurity proof failed");
return (DNS_R_NOTINSECURE);
out:
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
return (result);
}
/*%
* Reset state and revalidate the answer using DLV.
*/
static void
dlv_validator_start(dns_validator_t *val) {
isc_event_t *event;
validator_log(val, ISC_LOG_DEBUG(3), "dlv_validator_start");
/*
* Reset state and try again.
*/
val->attributes &= VALATTR_DLVTRIED;
val->options &= ~DNS_VALIDATOR_DLV;
event = (isc_event_t *)val->event;
isc_task_send(val->task, &event);
}
/*%
* Start the validation process.
*
* Attempt to validate the answer based on the category it appears to
* fall in.
* \li 1. secure positive answer.
* \li 2. unsecure positive answer.
* \li 3. a negative answer (secure or unsecure).
*
* Note a answer that appears to be a secure positive answer may actually
* be an unsecure positive answer.
*/
static void
validator_start(isc_task_t *task, isc_event_t *event) {
dns_validator_t *val;
dns_validatorevent_t *vevent;
isc_boolean_t want_destroy = ISC_FALSE;
isc_result_t result = ISC_R_FAILURE;
UNUSED(task);
REQUIRE(event->ev_type == DNS_EVENT_VALIDATORSTART);
vevent = (dns_validatorevent_t *)event;
val = vevent->validator;
/* If the validator has been canceled, val->event == NULL */
if (val->event == NULL)
return;
if (DLVTRIED(val))
validator_log(val, ISC_LOG_DEBUG(3), "restarting using DLV");
else
validator_log(val, ISC_LOG_DEBUG(3), "starting");
LOCK(&val->lock);
if ((val->options & DNS_VALIDATOR_DLV) != 0 &&
val->event->rdataset != NULL) {
validator_log(val, ISC_LOG_DEBUG(3), "looking for DLV");
result = startfinddlvsep(val, dns_rootname);
} else if (val->event->rdataset != NULL &&
val->event->sigrdataset != NULL) {
isc_result_t saved_result;
/*
* This looks like a simple validation. We say "looks like"
* because it might end up requiring an insecurity proof.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"attempting positive response validation");
INSIST(dns_rdataset_isassociated(val->event->rdataset));
INSIST(dns_rdataset_isassociated(val->event->sigrdataset));
result = start_positive_validation(val);
if (result == DNS_R_NOVALIDSIG &&
(val->attributes & VALATTR_TRIEDVERIFY) == 0)
{
saved_result = result;
validator_log(val, ISC_LOG_DEBUG(3),
"falling back to insecurity proof");
val->attributes |= VALATTR_INSECURITY;
result = proveunsecure(val, ISC_FALSE, ISC_FALSE);
if (result == DNS_R_NOTINSECURE)
result = saved_result;
}
} else if (val->event->rdataset != NULL &&
val->event->rdataset->type != 0) {
/*
* This is either an unsecure subdomain or a response from
* a broken server.
*/
INSIST(dns_rdataset_isassociated(val->event->rdataset));
validator_log(val, ISC_LOG_DEBUG(3),
"attempting insecurity proof");
val->attributes |= VALATTR_INSECURITY;
result = proveunsecure(val, ISC_FALSE, ISC_FALSE);
if (result == DNS_R_NOTINSECURE)
validator_log(val, ISC_LOG_INFO,
"got insecure response; "
"parent indicates it should be secure");
} else if (val->event->rdataset == NULL &&
val->event->sigrdataset == NULL)
{
/*
* This is a nonexistence validation.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"attempting negative response validation");
if (val->event->message->rcode == dns_rcode_nxdomain) {
val->attributes |= VALATTR_NEEDNOQNAME;
val->attributes |= VALATTR_NEEDNOWILDCARD;
} else
val->attributes |= VALATTR_NEEDNODATA;
result = nsecvalidate(val, ISC_FALSE);
} else if (val->event->rdataset != NULL &&
val->event->rdataset->type == 0)
{
/*
* This is a nonexistence validation.
*/
validator_log(val, ISC_LOG_DEBUG(3),
"attempting negative response validation");
if (val->event->rdataset->covers == dns_rdatatype_any) {
val->attributes |= VALATTR_NEEDNOQNAME;
val->attributes |= VALATTR_NEEDNOWILDCARD;
} else
val->attributes |= VALATTR_NEEDNODATA;
result = nsecvalidate(val, ISC_FALSE);
} else {
/*
* This shouldn't happen.
*/
INSIST(0);
}
if (result != DNS_R_WAIT) {
want_destroy = exit_check(val);
validator_done(val, result);
}
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
}
isc_result_t
dns_validator_create(dns_view_t *view, dns_name_t *name, dns_rdatatype_t type,
dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset,
dns_message_t *message, unsigned int options,
isc_task_t *task, isc_taskaction_t action, void *arg,
dns_validator_t **validatorp)
{
isc_result_t result = ISC_R_FAILURE;
dns_validator_t *val;
isc_task_t *tclone = NULL;
dns_validatorevent_t *event;
REQUIRE(name != NULL);
REQUIRE(rdataset != NULL ||
(rdataset == NULL && sigrdataset == NULL && message != NULL));
REQUIRE(validatorp != NULL && *validatorp == NULL);
val = isc_mem_get(view->mctx, sizeof(*val));
if (val == NULL)
return (ISC_R_NOMEMORY);
val->view = NULL;
dns_view_weakattach(view, &val->view);
event = (dns_validatorevent_t *)
isc_event_allocate(view->mctx, task,
DNS_EVENT_VALIDATORSTART,
validator_start, NULL,
sizeof(dns_validatorevent_t));
if (event == NULL) {
result = ISC_R_NOMEMORY;
goto cleanup_val;
}
isc_task_attach(task, &tclone);
event->validator = val;
event->result = ISC_R_FAILURE;
event->name = name;
event->type = type;
event->rdataset = rdataset;
event->sigrdataset = sigrdataset;
event->message = message;
memset(event->proofs, 0, sizeof(event->proofs));
event->optout = ISC_FALSE;
result = isc_mutex_init(&val->lock);
if (result != ISC_R_SUCCESS)
goto cleanup_event;
val->event = event;
val->options = options;
val->attributes = 0;
val->fetch = NULL;
val->subvalidator = NULL;
val->parent = NULL;
val->keytable = NULL;
result = dns_view_getsecroots(val->view, &val->keytable);
if (result != ISC_R_SUCCESS)
return (result);
val->keynode = NULL;
val->key = NULL;
val->siginfo = NULL;
val->task = task;
val->action = action;
val->arg = arg;
val->labels = 0;
val->currentset = NULL;
val->keyset = NULL;
val->dsset = NULL;
dns_rdataset_init(&val->dlv);
val->seensig = ISC_FALSE;
val->havedlvsep = ISC_FALSE;
val->depth = 0;
val->authcount = 0;
val->authfail = 0;
val->mustbesecure = dns_resolver_getmustbesecure(view->resolver, name);
dns_rdataset_init(&val->frdataset);
dns_rdataset_init(&val->fsigrdataset);
dns_fixedname_init(&val->wild);
dns_fixedname_init(&val->nearest);
dns_fixedname_init(&val->closest);
ISC_LINK_INIT(val, link);
val->magic = VALIDATOR_MAGIC;
if ((options & DNS_VALIDATOR_DEFER) == 0)
isc_task_send(task, ISC_EVENT_PTR(&event));
*validatorp = val;
return (ISC_R_SUCCESS);
cleanup_event:
isc_task_detach(&tclone);
isc_event_free(ISC_EVENT_PTR(&event));
cleanup_val:
dns_view_weakdetach(&val->view);
isc_mem_put(view->mctx, val, sizeof(*val));
return (result);
}
void
dns_validator_send(dns_validator_t *validator) {
isc_event_t *event;
REQUIRE(VALID_VALIDATOR(validator));
LOCK(&validator->lock);
INSIST((validator->options & DNS_VALIDATOR_DEFER) != 0);
event = (isc_event_t *)validator->event;
validator->options &= ~DNS_VALIDATOR_DEFER;
UNLOCK(&validator->lock);
isc_task_send(validator->task, ISC_EVENT_PTR(&event));
}
void
dns_validator_cancel(dns_validator_t *validator) {
REQUIRE(VALID_VALIDATOR(validator));
LOCK(&validator->lock);
validator_log(validator, ISC_LOG_DEBUG(3), "dns_validator_cancel");
if ((validator->attributes & VALATTR_CANCELED) == 0) {
validator->attributes |= VALATTR_CANCELED;
if (validator->event != NULL) {
if (validator->fetch != NULL)
dns_resolver_cancelfetch(validator->fetch);
if (validator->subvalidator != NULL)
dns_validator_cancel(validator->subvalidator);
if ((validator->options & DNS_VALIDATOR_DEFER) != 0) {
validator->options &= ~DNS_VALIDATOR_DEFER;
validator_done(validator, ISC_R_CANCELED);
}
}
}
UNLOCK(&validator->lock);
}
static void
destroy(dns_validator_t *val) {
isc_mem_t *mctx;
REQUIRE(SHUTDOWN(val));
REQUIRE(val->event == NULL);
REQUIRE(val->fetch == NULL);
if (val->keynode != NULL)
dns_keytable_detachkeynode(val->keytable, &val->keynode);
else if (val->key != NULL)
dst_key_free(&val->key);
if (val->keytable != NULL)
dns_keytable_detach(&val->keytable);
if (val->subvalidator != NULL)
dns_validator_destroy(&val->subvalidator);
if (val->havedlvsep)
dns_rdataset_disassociate(&val->dlv);
if (dns_rdataset_isassociated(&val->frdataset))
dns_rdataset_disassociate(&val->frdataset);
if (dns_rdataset_isassociated(&val->fsigrdataset))
dns_rdataset_disassociate(&val->fsigrdataset);
mctx = val->view->mctx;
if (val->siginfo != NULL)
isc_mem_put(mctx, val->siginfo, sizeof(*val->siginfo));
DESTROYLOCK(&val->lock);
dns_view_weakdetach(&val->view);
val->magic = 0;
isc_mem_put(mctx, val, sizeof(*val));
}
void
dns_validator_destroy(dns_validator_t **validatorp) {
dns_validator_t *val;
isc_boolean_t want_destroy = ISC_FALSE;
REQUIRE(validatorp != NULL);
val = *validatorp;
REQUIRE(VALID_VALIDATOR(val));
LOCK(&val->lock);
val->attributes |= VALATTR_SHUTDOWN;
validator_log(val, ISC_LOG_DEBUG(3), "dns_validator_destroy");
want_destroy = exit_check(val);
UNLOCK(&val->lock);
if (want_destroy)
destroy(val);
*validatorp = NULL;
}
static void
validator_logv(dns_validator_t *val, isc_logcategory_t *category,
isc_logmodule_t *module, int level, const char *fmt, va_list ap)
{
char msgbuf[2048];
static const char spaces[] = " *";
int depth = val->depth * 2;
vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap);
if ((unsigned int) depth >= sizeof spaces)
depth = sizeof spaces - 1;
if (val->event != NULL && val->event->name != NULL) {
char namebuf[DNS_NAME_FORMATSIZE];
char typebuf[DNS_RDATATYPE_FORMATSIZE];
dns_name_format(val->event->name, namebuf, sizeof(namebuf));
dns_rdatatype_format(val->event->type, typebuf,
sizeof(typebuf));
isc_log_write(dns_lctx, category, module, level,
"%.*svalidating @%p: %s %s: %s", depth, spaces,
val, namebuf, typebuf, msgbuf);
} else {
isc_log_write(dns_lctx, category, module, level,
"%.*svalidator @%p: %s", depth, spaces,
val, msgbuf);
}
}
static void
validator_log(dns_validator_t *val, int level, const char *fmt, ...) {
va_list ap;
if (! isc_log_wouldlog(dns_lctx, level))
return;
va_start(ap, fmt);
validator_logv(val, DNS_LOGCATEGORY_DNSSEC,
DNS_LOGMODULE_VALIDATOR, level, fmt, ap);
va_end(ap);
}
static void
validator_logcreate(dns_validator_t *val,
dns_name_t *name, dns_rdatatype_t type,
const char *caller, const char *operation)
{
char namestr[DNS_NAME_FORMATSIZE];
char typestr[DNS_RDATATYPE_FORMATSIZE];
dns_name_format(name, namestr, sizeof(namestr));
dns_rdatatype_format(type, typestr, sizeof(typestr));
validator_log(val, ISC_LOG_DEBUG(9), "%s: creating %s for %s %s",
caller, operation, namestr, typestr);
}