return;
(void)dns_cache_store(qstate->env, &qstate->qinfo,
qstate->return_msg->rep, 0, qstate->prefetch_leeway, 0,
- qstate->region, store_flags);
+ qstate->region, store_flags, qstate->qstarttime);
}
/**
if(!go_on)
return 1; /* skip this one, not all references satisfied */
- if(!dns_cache_store(&worker->env, &qinf, &rep, 0, 0, 0, NULL, flags)) {
+ if(!dns_cache_store(&worker->env, &qinf, &rep, 0, 0, 0, NULL, flags,
+ *worker->env.now)) {
log_warn("error out of memory");
return 0;
}
while(1) {
dp = dns_cache_find_delegation(&worker->env, nm, nmlen,
qinfo.qtype, qinfo.qclass, region, &msg,
- *worker->env.now);
+ *worker->env.now, 0, NULL, 0);
if(!dp) {
return ssl_printf(ssl, "no delegation from "
"cache; goes to configured roots\n");
dp = dns_cache_find_delegation(&worker->env, qinfo->qname,
qinfo->qname_len, qinfo->qtype, qinfo->qclass,
- worker->scratchpad, &msg, timenow);
+ worker->scratchpad, &msg, timenow, 0, NULL, 0);
if(!dp) { /* no delegation, need to reprime */
return 0;
}
if ( (!iq || !iq->started_no_cache_store) &&
qstate->return_msg && qstate->return_msg->rep &&
!dns_cache_store(qstate->env, &qstate->qinfo, qstate->return_msg->rep,
- 0, 0, 0, NULL, qstate->query_flags))
+ 0, 0, 0, NULL, qstate->query_flags, qstate->qstarttime))
log_err("out of memory");
/* do nothing */
/* Store the generated response in cache. */
if ( (!super_dq || !super_dq->started_no_cache_store) &&
!dns_cache_store(super->env, &super->qinfo, super->return_msg->rep,
- 0, 0, 0, NULL, super->query_flags))
+ 0, 0, 0, NULL, super->query_flags, qstate->qstarttime))
log_err("out of memory");
}
+1 August 2022: Wouter
+ - Fix the novel ghost domain issues CVE-2022-30698 and CVE-2022-30699.
+
19 July 2022: George
- Update documentation for 'outbound-msg-retry:'.
/* Store A/AAAA in cache. */
if(!dns_cache_store(qstate->env, &qstate->qinfo,
qstate->return_msg->rep, 0, qstate->prefetch_leeway,
- 0, qstate->region, qstate->query_flags)) {
+ 0, qstate->region, qstate->query_flags, qstate->qstarttime)) {
log_err("ipsecmod: out of memory caching record");
}
qstate->ext_state[id] = module_finished;
void
iter_dns_store(struct module_env* env, struct query_info* msgqinf,
struct reply_info* msgrep, int is_referral, time_t leeway, int pside,
- struct regional* region, uint16_t flags)
+ struct regional* region, uint16_t flags, time_t qstarttime)
{
if(!dns_cache_store(env, msgqinf, msgrep, is_referral, leeway,
- pside, region, flags))
+ pside, region, flags, qstarttime))
log_err("out of memory: cannot store data in cache");
}
* can be prefetch-updates.
* @param region: to copy modified (cache is better) rrs back to.
* @param flags: with BIT_CD for dns64 AAAA translated queries.
+ * @param qstarttime: time of query start.
* return void, because we are not interested in alloc errors,
* the iterator and validator can operate on the results in their
* scratch space (the qstate.region) and are not dependent on the cache.
*/
void iter_dns_store(struct module_env* env, struct query_info* qinf,
struct reply_info* rep, int is_referral, time_t leeway, int pside,
- struct regional* region, uint16_t flags);
+ struct regional* region, uint16_t flags, time_t qstarttime);
/**
* Select randomly with n/m probability.
err.security = sec_status_indeterminate;
verbose(VERB_ALGO, "store error response in message cache");
iter_dns_store(qstate->env, &qstate->qinfo, &err, 0, 0, 0, NULL,
- qstate->query_flags);
+ qstate->query_flags, qstate->qstarttime);
}
return error_response(qstate, id, rcode);
}
iq->dp = dns_cache_find_delegation(qstate->env, delname,
delnamelen, iq->qchase.qtype, iq->qchase.qclass,
qstate->region, &iq->deleg_msg,
- *qstate->env->now+qstate->prefetch_leeway);
+ *qstate->env->now+qstate->prefetch_leeway, 1,
+ dpname, dpnamelen);
else iq->dp = NULL;
/* If the cache has returned nothing, then we have a
subiq->dp = dns_cache_find_delegation(qstate->env,
name, namelen, qtype, qclass, subq->region,
&subiq->deleg_msg,
- *qstate->env->now+subq->prefetch_leeway);
+ *qstate->env->now+subq->prefetch_leeway,
+ 1, NULL, 0);
/* if no dp, then it's from root, refetch unneeded */
if(subiq->dp) {
subiq->dnssec_expected = iter_indicates_dnssec(
iq->qchase.qtype != iq->response->qinfo.qtype,
qstate->prefetch_leeway,
iq->dp&&iq->dp->has_parent_side_NS,
- qstate->region, qstate->query_flags);
+ qstate->region, qstate->query_flags,
+ qstate->qstarttime);
/* close down outstanding requests to be discarded */
outbound_list_clear(&iq->outlist);
iq->num_current_queries = 0;
/* Store the referral under the current query */
/* no prefetch-leeway, since its not the answer */
iter_dns_store(qstate->env, &iq->response->qinfo,
- iq->response->rep, 1, 0, 0, NULL, 0);
+ iq->response->rep, 1, 0, 0, NULL, 0,
+ qstate->qstarttime);
if(iq->store_parent_NS)
iter_store_parentside_NS(qstate->env,
iq->response->rep);
iter_dns_store(qstate->env, &iq->response->qinfo,
iq->response->rep, 1, qstate->prefetch_leeway,
iq->dp&&iq->dp->has_parent_side_NS, NULL,
- qstate->query_flags);
+ qstate->query_flags, qstate->qstarttime);
/* set the current request's qname to the new value. */
iq->qchase.qname = sname;
iq->qchase.qname_len = snamelen;
iter_dns_store(qstate->env, &qstate->qinfo,
iq->response->rep, 0, qstate->prefetch_leeway,
iq->dp&&iq->dp->has_parent_side_NS,
- qstate->region, qstate->query_flags);
+ qstate->region, qstate->query_flags,
+ qstate->qstarttime);
}
}
qstate->return_rcode = LDNS_RCODE_NOERROR;
/* Functions which we will need to lookup delegations */
struct delegpt* dns_cache_find_delegation(struct module_env* env,
uint8_t* qname, size_t qnamelen, uint16_t qtype, uint16_t qclass,
- struct regional* region, struct dns_msg** msg, uint32_t timenow);
+ struct regional* region, struct dns_msg** msg, uint32_t timenow,
+ int noexpiredabove, uint8_t* expiretop, size_t expiretoplen);
int iter_dp_is_useless(struct query_info* qinfo, uint16_t qflags,
struct delegpt* dp, int supports_ipv4, int supports_ipv6);
struct iter_hints_stub* hints_lookup_stub(struct iter_hints* hints,
qinfo.qclass = LDNS_RR_CLASS_IN;
while(1) {
- dp = dns_cache_find_delegation(qstate->env, (uint8_t*)nm, nmlen, qinfo.qtype, qinfo.qclass, region, &msg, timenow);
+ dp = dns_cache_find_delegation(qstate->env, (uint8_t*)nm, nmlen, qinfo.qtype, qinfo.qclass, region, &msg, timenow, 0, NULL, 0);
if(!dp)
return NULL;
if(iter_dp_is_useless(&qinfo, BIT_RD, dp,
}
return dns_cache_store(qstate->env, qinfo, msgrep, is_referral,
- qstate->prefetch_leeway, 0, NULL, qstate->query_flags);
+ qstate->prefetch_leeway, 0, NULL, qstate->query_flags,
+ qstate->qstarttime);
}
/* Invalidate the message associated with query_info stored in message cache */
* in a prefetch situation to be updated (without becoming sticky).
* @param qrep: update rrsets here if cache is better
* @param region: for qrep allocs.
+ * @param qstarttime: time when delegations were looked up, this is perhaps
+ * earlier than the time in now. The time is used to determine if RRsets
+ * of type NS have expired, so that they can only be updated using
+ * lookups of delegation points that did not use them, since they had
+ * expired then.
*/
static void
store_rrsets(struct module_env* env, struct reply_info* rep, time_t now,
time_t leeway, int pside, struct reply_info* qrep,
- struct regional* region)
+ struct regional* region, time_t qstarttime)
{
size_t i;
/* see if rrset already exists in cache, if not insert it. */
rep->ref[i].id = rep->rrsets[i]->id;
/* update ref if it was in the cache */
switch(rrset_cache_update(env->rrset_cache, &rep->ref[i],
- env->alloc, now + ((ntohs(rep->ref[i].key->rk.type)==
- LDNS_RR_TYPE_NS && !pside)?0:leeway))) {
+ env->alloc, ((ntohs(rep->ref[i].key->rk.type)==
+ LDNS_RR_TYPE_NS && !pside)?qstarttime:now + leeway))) {
case 0: /* ref unchanged, item inserted */
break;
case 2: /* ref updated, cache is superior */
void
dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
hashvalue_type hash, struct reply_info* rep, time_t leeway, int pside,
- struct reply_info* qrep, uint32_t flags, struct regional* region)
+ struct reply_info* qrep, uint32_t flags, struct regional* region,
+ time_t qstarttime)
{
struct msgreply_entry* e;
time_t ttl = rep->ttl;
/* there was a reply_info_sortref(rep) here but it seems to be
* unnecessary, because the cache gets locked per rrset. */
reply_info_set_ttls(rep, *env->now);
- store_rrsets(env, rep, *env->now, leeway, pside, qrep, region);
+ store_rrsets(env, rep, *env->now, leeway, pside, qrep, region,
+ qstarttime);
if(ttl == 0 && !(flags & DNSCACHE_STORE_ZEROTTL)) {
/* we do not store the message, but we did store the RRs,
* which could be useful for delegation information */
slabhash_insert(env->msg_cache, hash, &e->entry, rep, env->alloc);
}
+/** see if an rrset is expired above the qname, return upper qname. */
+static int
+rrset_expired_above(struct module_env* env, uint8_t** qname, size_t* qnamelen,
+ uint16_t searchtype, uint16_t qclass, time_t now, uint8_t* expiretop,
+ size_t expiretoplen)
+{
+ struct ub_packed_rrset_key *rrset;
+ uint8_t lablen;
+
+ while(*qnamelen > 0) {
+ /* look one label higher */
+ lablen = **qname;
+ *qname += lablen + 1;
+ *qnamelen -= lablen + 1;
+ if(*qnamelen <= 0)
+ break;
+
+ /* looks up with a time of 0, to see expired entries */
+ if((rrset = rrset_cache_lookup(env->rrset_cache, *qname,
+ *qnamelen, searchtype, qclass, 0, 0, 0))) {
+ struct packed_rrset_data* data =
+ (struct packed_rrset_data*)rrset->entry.data;
+ if(now > data->ttl) {
+ /* it is expired, this is not wanted */
+ lock_rw_unlock(&rrset->entry.lock);
+ log_nametypeclass(VERB_ALGO, "this rrset is expired", *qname, searchtype, qclass);
+ return 1;
+ }
+ /* it is not expired, continue looking */
+ lock_rw_unlock(&rrset->entry.lock);
+ }
+
+ /* do not look above the expiretop. */
+ if(expiretop && *qnamelen == expiretoplen &&
+ query_dname_compare(*qname, expiretop)==0)
+ break;
+ }
+ return 0;
+}
+
/** find closest NS or DNAME and returns the rrset (locked) */
static struct ub_packed_rrset_key*
find_closest_of_type(struct module_env* env, uint8_t* qname, size_t qnamelen,
- uint16_t qclass, time_t now, uint16_t searchtype, int stripfront)
+ uint16_t qclass, time_t now, uint16_t searchtype, int stripfront,
+ int noexpiredabove, uint8_t* expiretop, size_t expiretoplen)
{
struct ub_packed_rrset_key *rrset;
uint8_t lablen;
/* snip off front part of qname until the type is found */
while(qnamelen > 0) {
if((rrset = rrset_cache_lookup(env->rrset_cache, qname,
- qnamelen, searchtype, qclass, 0, now, 0)))
- return rrset;
+ qnamelen, searchtype, qclass, 0, now, 0))) {
+ uint8_t* origqname = qname;
+ size_t origqnamelen = qnamelen;
+ if(!noexpiredabove)
+ return rrset;
+ /* if expiretop set, do not look above it, but
+ * qname is equal, so the just found result is also
+ * the nonexpired above part. */
+ if(expiretop && qnamelen == expiretoplen &&
+ query_dname_compare(qname, expiretop)==0)
+ return rrset;
+ /* check for expiry, but we have to let go of the rrset
+ * for the lock ordering */
+ lock_rw_unlock(&rrset->entry.lock);
+ /* the expired_above function always takes off one
+ * label (if qnamelen>0) and returns the final qname
+ * where it searched, so we can continue from there
+ * turning the O N*N search into O N. */
+ if(!rrset_expired_above(env, &qname, &qnamelen,
+ searchtype, qclass, now, expiretop,
+ expiretoplen)) {
+ /* we want to return rrset, but it may be
+ * gone from cache, if so, just loop like
+ * it was not in the cache in the first place.
+ */
+ if((rrset = rrset_cache_lookup(env->
+ rrset_cache, origqname, origqnamelen,
+ searchtype, qclass, 0, now, 0))) {
+ return rrset;
+ }
+ }
+ log_nametypeclass(VERB_ALGO, "ignoring rrset because expired rrsets exist above it", origqname, searchtype, qclass);
+ continue;
+ }
/* snip off front label */
lablen = *qname;
struct delegpt*
dns_cache_find_delegation(struct module_env* env, uint8_t* qname,
size_t qnamelen, uint16_t qtype, uint16_t qclass,
- struct regional* region, struct dns_msg** msg, time_t now)
+ struct regional* region, struct dns_msg** msg, time_t now,
+ int noexpiredabove, uint8_t* expiretop, size_t expiretoplen)
{
/* try to find closest NS rrset */
struct ub_packed_rrset_key* nskey;
struct delegpt* dp;
nskey = find_closest_of_type(env, qname, qnamelen, qclass, now,
- LDNS_RR_TYPE_NS, 0);
+ LDNS_RR_TYPE_NS, 0, noexpiredabove, expiretop, expiretoplen);
if(!nskey) /* hope the caller has hints to prime or something */
return NULL;
nsdata = (struct packed_rrset_data*)nskey->entry.data;
* consistent with the DNAME */
if(!no_partial &&
(rrset=find_closest_of_type(env, qname, qnamelen, qclass, now,
- LDNS_RR_TYPE_DNAME, 1))) {
+ LDNS_RR_TYPE_DNAME, 1, 0, NULL, 0))) {
/* synthesize a DNAME+CNAME message based on this */
enum sec_status sec_status = sec_status_unchecked;
struct dns_msg* msg = synth_dname_msg(rrset, region, now, &k,
int
dns_cache_store(struct module_env* env, struct query_info* msgqinf,
struct reply_info* msgrep, int is_referral, time_t leeway, int pside,
- struct regional* region, uint32_t flags)
+ struct regional* region, uint32_t flags, time_t qstarttime)
{
struct reply_info* rep = NULL;
/* alloc, malloc properly (not in region, like msg is) */
/*ignore ret: it was in the cache, ref updated */
/* no leeway for typeNS */
(void)rrset_cache_update(env->rrset_cache, &ref,
- env->alloc, *env->now +
+ env->alloc,
((ntohs(ref.key->rk.type)==LDNS_RR_TYPE_NS
- && !pside) ? 0:leeway));
+ && !pside) ? qstarttime:*env->now + leeway));
}
free(rep);
return 1;
rep->flags &= ~(BIT_AA | BIT_CD);
h = query_info_hash(&qinf, (uint16_t)flags);
dns_cache_store_msg(env, &qinf, h, rep, leeway, pside, msgrep,
- flags, region);
+ flags, region, qstarttime);
/* qname is used inside query_info_entrysetup, and set to
* NULL. If it has not been used, free it. free(0) is safe. */
free(qinf.qname);
* @param flags: flags with BIT_CD for AAAA queries in dns64 translation.
* The higher 16 bits are used internally to customize the cache policy.
* (See DNSCACHE_STORE_xxx flags).
+ * @param qstarttime: time when the query was started, and thus when the
+ * delegations were looked up.
* @return 0 on alloc error (out of memory).
*/
int dns_cache_store(struct module_env* env, struct query_info* qinf,
struct reply_info* rep, int is_referral, time_t leeway, int pside,
- struct regional* region, uint32_t flags);
+ struct regional* region, uint32_t flags, time_t qstarttime);
/**
* Store message in the cache. Stores in message cache and rrset cache.
* can be updated to full TTL even in prefetch situations.
* @param qrep: message that can be altered with better rrs from cache.
* @param flags: customization flags for the cache policy.
+ * @param qstarttime: time when the query was started, and thus when the
+ * delegations were looked up.
* @param region: to allocate into for qmsg.
*/
void dns_cache_store_msg(struct module_env* env, struct query_info* qinfo,
hashvalue_type hash, struct reply_info* rep, time_t leeway, int pside,
- struct reply_info* qrep, uint32_t flags, struct regional* region);
+ struct reply_info* qrep, uint32_t flags, struct regional* region,
+ time_t qstarttime);
/**
* Find a delegation from the cache.
* @param msg: if not NULL, delegation message is returned here, synthesized
* from the cache.
* @param timenow: the time now, for checking if TTL on cache entries is OK.
+ * @param noexpiredabove: if set, no expired NS rrsets above the one found
+ * are tolerated. It only returns delegations where the delegations above
+ * it are valid.
+ * @param expiretop: if not NULL, name where check for expiry ends for
+ * noexpiredabove.
+ * @param expiretoplen: length of expiretop dname.
* @return new delegation or NULL on error or if not found in cache.
*/
struct delegpt* dns_cache_find_delegation(struct module_env* env,
uint8_t* qname, size_t qnamelen, uint16_t qtype, uint16_t qclass,
- struct regional* region, struct dns_msg** msg, time_t timenow);
+ struct regional* region, struct dns_msg** msg, time_t timenow,
+ int noexpiredabove, uint8_t* expiretop, size_t expiretoplen);
/**
* generate dns_msg from cached message
mstate->s.no_cache_store = 0;
mstate->s.need_refetch = 0;
mstate->s.was_ratelimited = 0;
+ mstate->s.qstarttime = *env->now;
/* init modules */
for(i=0; i<env->mesh->mods.num; i++) {
SECTION QUESTION
. IN NS
SECTION ANSWER
-. IN NS K.ROOT-SERVERS.NET.
+. 86400 IN NS K.ROOT-SERVERS.NET.
SECTION ADDITIONAL
-K.ROOT-SERVERS.NET. IN A 193.0.14.129
+K.ROOT-SERVERS.NET. 86400 IN A 193.0.14.129
ENTRY_END
ENTRY_BEGIN
SECTION QUESTION
com. IN A
SECTION AUTHORITY
-com. IN NS a.gtld-servers.net.
+com. 86400 IN NS a.gtld-servers.net.
SECTION ADDITIONAL
-a.gtld-servers.net. IN A 192.5.6.30
+a.gtld-servers.net. 86400 IN A 192.5.6.30
ENTRY_END
RANGE_END
SECTION QUESTION
com. IN NS
SECTION ANSWER
-com. IN NS a.gtld-servers.net.
+com. 86400 IN NS a.gtld-servers.net.
SECTION ADDITIONAL
-a.gtld-servers.net. IN A 192.5.6.30
+a.gtld-servers.net. 86400 IN A 192.5.6.30
ENTRY_END
ENTRY_BEGIN
SECTION QUESTION
com. IN NS
SECTION ANSWER
-com. IN NS a.gtld-servers.net.
+com. 86400 IN NS a.gtld-servers.net.
SECTION ADDITIONAL
-a.gtld-servers.net. IN A 192.5.6.30
+a.gtld-servers.net. 86400 IN A 192.5.6.30
ENTRY_END
ENTRY_BEGIN
int need_refetch;
/** whether the query (or a subquery) was ratelimited */
int was_ratelimited;
+ /** time when query was started. This is when the qstate is created.
+ * This is used so that type NS data cannot be overwritten by them
+ * expiring while the lookup is in progress, using data fetched from
+ * those servers. By comparing expiry time with qstarttime for type NS.
+ */
+ time_t qstarttime;
/**
* Attributes of clients that share the qstate that may affect IP-based
if(!qstate->no_cache_store) {
if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo,
vq->orig_msg->rep, 0, qstate->prefetch_leeway, 0, NULL,
- qstate->query_flags)) {
+ qstate->query_flags, qstate->qstarttime)) {
log_err("out of memory caching validator results");
}
}
/* and this does not get prefetched, so no leeway */
if(!dns_cache_store(qstate->env, &vq->orig_msg->qinfo,
vq->orig_msg->rep, 1, 0, 0, NULL,
- qstate->query_flags)) {
+ qstate->query_flags, qstate->qstarttime)) {
log_err("out of memory caching validator results");
}
}
projects / thirdparty / unbound.git / commitdiff
