/*
* services/cache/dns.c - Cache services for DNS using msg and rrset caches.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** store rrsets in the rrset cache.
* @param env: module environment with caches.
* @param rep: contains list of rrsets to store.
* @param now: current time.
* @param leeway: during prefetch how much leeway to update TTLs.
* This makes rrsets (other than type NS) timeout sooner so they get
* updated with a new full TTL.
* Type NS does not get this, because it must not be refreshed from the
* child domain, but keep counting down properly.
* @param pside: if from parentside discovered NS, so that its NS is okay
* 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, time_t qstarttime)
{
size_t i;
time_t ttl, min_ttl = rep->ttl;
/* see if rrset already exists in cache, if not insert it. */
for(i=0; i<rep->rrset_count; i++) {
rep->ref[i].key = rep->rrsets[i];
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, ((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 */
if(region) {
struct ub_packed_rrset_key* ck;
lock_rw_rdlock(&rep->ref[i].key->entry.lock);
/* if deleted rrset, do not copy it */
if(rep->ref[i].key->id == 0 ||
rep->ref[i].id != rep->ref[i].key->id)
ck = NULL;
else ck = packed_rrset_copy_region(
rep->ref[i].key, region, now);
lock_rw_unlock(&rep->ref[i].key->entry.lock);
if(ck) {
/* use cached copy if memory allows */
qrep->rrsets[i] = ck;
}
}
/* no break: also copy key item */
/* the line below is matched by gcc regex and silences
* the fallthrough warning */
ATTR_FALLTHROUGH
/* fallthrough */
case 1: /* ref updated, item inserted */
rep->rrsets[i] = rep->ref[i].key;
/* ref was updated; make sure the message ttl is
* updated to the minimum of the current rrsets. */
lock_rw_rdlock(&rep->ref[i].key->entry.lock);
/* if deleted, skip ttl update. */
if(rep->ref[i].key->id != 0 &&
rep->ref[i].id == rep->ref[i].key->id) {
ttl = ((struct packed_rrset_data*)
rep->rrsets[i]->entry.data)->ttl;
if(ttl < min_ttl) min_ttl = ttl;
}
lock_rw_unlock(&rep->ref[i].key->entry.lock);
}
}
if(min_ttl < rep->ttl) {
rep->ttl = min_ttl;
rep->prefetch_ttl = PREFETCH_TTL_CALC(rep->ttl);
rep->serve_expired_ttl = rep->ttl + SERVE_EXPIRED_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,
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 */
verbose(VERB_ALGO, "TTL 0: dropped msg from cache");
reply_info_delete(rep, NULL);
/* if the message is in the cache, remove that msg,
* so that the TTL 0 response can be returned for future
* responses (i.e. don't get answered from
* cache, but instead go to recursion to get this TTL0
* response).
* Possible messages that could be in the cache:
* - SERVFAIL
* - NXDOMAIN
* - NODATA
* - an older record that is expired
* - an older record that did not yet expire */
msg_cache_remove(env, qinfo->qname, qinfo->qname_len,
qinfo->qtype, qinfo->qclass, flags);
return;
}
/* store msg in the cache */
reply_info_sortref(rep);
if(!(e = query_info_entrysetup(qinfo, rep, hash))) {
log_err("store_msg: malloc failed");
reply_info_delete(rep, NULL);
return;
}
slabhash_insert(env->msg_cache, hash, &e->entry, rep, env->alloc);
}
/** 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,
int noexpiredabove, uint8_t* expiretop, size_t expiretoplen)
{
struct ub_packed_rrset_key *rrset;
uint8_t lablen;
if(stripfront) {
/* strip off so that DNAMEs have strict subdomain match */
lablen = *qname;
qname += lablen + 1;
qnamelen -= lablen + 1;
}
/* 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))) {
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 rrset_cache_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_cache_expired_above(env->rrset_cache, &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;
}
/** find and add A and AAAA records for nameservers in delegpt */
static int
find_add_addrs(struct module_env* env, uint16_t qclass,
struct regional* region, struct delegpt* dp, time_t now,
struct dns_msg** msg)
{
struct delegpt_ns* ns;
struct msgreply_entry* neg;
struct ub_packed_rrset_key* akey;
for(ns = dp->nslist; ns; ns = ns->next) {
akey = rrset_cache_lookup(env->rrset_cache, ns->name,
ns->namelen, LDNS_RR_TYPE_A, qclass, 0, now, 0);
if(akey) {
if(!delegpt_add_rrset_A(dp, region, akey, 0, NULL)) {
lock_rw_unlock(&akey->entry.lock);
return 0;
}
if(msg)
addr_to_additional(akey, region, *msg, now);
lock_rw_unlock(&akey->entry.lock);
} else {
/* BIT_CD on false because delegpt lookup does
* not use dns64 translation */
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_A, qclass, 0, now, 0);
if(neg) {
delegpt_add_neg_msg(dp, neg);
lock_rw_unlock(&neg->entry.lock);
}
}
akey = rrset_cache_lookup(env->rrset_cache, ns->name,
ns->namelen, LDNS_RR_TYPE_AAAA, qclass, 0, now, 0);
if(akey) {
if(!delegpt_add_rrset_AAAA(dp, region, akey, 0, NULL)) {
lock_rw_unlock(&akey->entry.lock);
return 0;
}
if(msg)
addr_to_additional(akey, region, *msg, now);
lock_rw_unlock(&akey->entry.lock);
} else {
/* BIT_CD on false because delegpt lookup does
* not use dns64 translation */
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_AAAA, qclass, 0, now, 0);
/* Because recursion for lookup uses BIT_CD, check
* for that so it stops the recursion lookup, if a
* negative answer is cached. Because the cache uses
* the CD flag for type AAAA. */
if(!neg)
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_AAAA, qclass, BIT_CD, now, 0);
if(neg) {
delegpt_add_neg_msg(dp, neg);
lock_rw_unlock(&neg->entry.lock);
}
}
}
return 1;
}
/** find and add A and AAAA records for missing nameservers in delegpt */
int
cache_fill_missing(struct module_env* env, uint16_t qclass,
struct regional* region, struct delegpt* dp, uint32_t flags)
{
struct delegpt_ns* ns;
struct msgreply_entry* neg;
struct ub_packed_rrset_key* akey;
time_t now = *env->now;
for(ns = dp->nslist; ns; ns = ns->next) {
if(ns->cache_lookup_count > ITERATOR_NAME_CACHELOOKUP_MAX)
continue;
ns->cache_lookup_count++;
akey = rrset_cache_lookup(env->rrset_cache, ns->name,
ns->namelen, LDNS_RR_TYPE_A, qclass, flags, now, 0);
if(akey) {
if(!delegpt_add_rrset_A(dp, region, akey, ns->lame,
NULL)) {
lock_rw_unlock(&akey->entry.lock);
return 0;
}
log_nametypeclass(VERB_ALGO, "found in cache",
ns->name, LDNS_RR_TYPE_A, qclass);
lock_rw_unlock(&akey->entry.lock);
} else {
/* BIT_CD on false because delegpt lookup does
* not use dns64 translation */
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_A, qclass, 0, now, 0);
if(neg) {
delegpt_add_neg_msg(dp, neg);
lock_rw_unlock(&neg->entry.lock);
}
}
akey = rrset_cache_lookup(env->rrset_cache, ns->name,
ns->namelen, LDNS_RR_TYPE_AAAA, qclass, flags, now, 0);
if(akey) {
if(!delegpt_add_rrset_AAAA(dp, region, akey, ns->lame,
NULL)) {
lock_rw_unlock(&akey->entry.lock);
return 0;
}
log_nametypeclass(VERB_ALGO, "found in cache",
ns->name, LDNS_RR_TYPE_AAAA, qclass);
lock_rw_unlock(&akey->entry.lock);
} else {
/* BIT_CD on false because delegpt lookup does
* not use dns64 translation */
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_AAAA, qclass, 0, now, 0);
/* Because recursion for lookup uses BIT_CD, check
* for that so it stops the recursion lookup, if a
* negative answer is cached. Because the cache uses
* the CD flag for type AAAA. */
if(!neg)
neg = msg_cache_lookup(env, ns->name, ns->namelen,
LDNS_RR_TYPE_AAAA, qclass, BIT_CD, now, 0);
if(neg) {
delegpt_add_neg_msg(dp, neg);
lock_rw_unlock(&neg->entry.lock);
}
}
}
return 1;
}
/** find and add DS or NSEC to delegation msg */
static void
find_add_ds(struct module_env* env, struct regional* region,
struct dns_msg* msg, struct delegpt* dp, time_t now)
{
/* Lookup the DS or NSEC at the delegation point. */
struct ub_packed_rrset_key* rrset = rrset_cache_lookup(
env->rrset_cache, dp->name, dp->namelen, LDNS_RR_TYPE_DS,
msg->qinfo.qclass, 0, now, 0);
if(!rrset) {
/* NOTE: this won't work for alternate NSEC schemes
* (opt-in, NSEC3) */
rrset = rrset_cache_lookup(env->rrset_cache, dp->name,
dp->namelen, LDNS_RR_TYPE_NSEC, msg->qinfo.qclass,
0, now, 0);
/* Note: the PACKED_RRSET_NSEC_AT_APEX flag is not used.
* since this is a referral, we need the NSEC at the parent
* side of the zone cut, not the NSEC at apex side. */
if(rrset && nsec_has_type(rrset, LDNS_RR_TYPE_DS)) {
lock_rw_unlock(&rrset->entry.lock);
rrset = NULL; /* discard wrong NSEC */
}
}
if(rrset) {
/* add it to auth section. This is the second rrset. */
if((msg->rep->rrsets[msg->rep->rrset_count] =
packed_rrset_copy_region(rrset, region, now))) {
msg->rep->ns_numrrsets++;
msg->rep->rrset_count++;
}
lock_rw_unlock(&rrset->entry.lock);
}
}
/* lookup first, this has both NXdomains and ANSWER responses */
k.qname = qname;
k.qname_len = qnamelen;
k.qtype = qtype;
k.qclass = qclass;
k.local_alias = NULL;
h = query_info_hash(&k, flags);
e = slabhash_lookup(env->msg_cache, h, &k, 0);
if(e) {
struct msgreply_entry* key = (struct msgreply_entry*)e->key;
struct reply_info* data = (struct reply_info*)e->data;
struct dns_msg* msg = tomsg(env, &key->key, data, region, now, 0,
scratch);
if(msg) {
lock_rw_unlock(&e->lock);
return msg;
}
/* could be msg==NULL; due to TTL or not all rrsets available */
lock_rw_unlock(&e->lock);
}
/* see if a DNAME exists. Checked for first, to enforce that DNAMEs
* are more important, the CNAME is resynthesized and thus
* consistent with the DNAME */
if(!no_partial &&
(rrset=find_closest_of_type(env, qname, qnamelen, qclass, now,
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,
&sec_status);
if(msg) {
struct ub_packed_rrset_key* cname_rrset;
lock_rw_unlock(&rrset->entry.lock);
/* now, after unlocking the DNAME rrset lock,
* check the sec_status, and see if we need to look
* up the CNAME record associated before it can
* be used */
/* normally, only secure DNAMEs allowed from cache*/
if(sec_status == sec_status_secure)
return msg;
/* but if we have a CNAME cached with this name, then we
* have previously already allowed this name to pass.
* the next cache lookup is going to fetch that CNAME itself,
* but it is better to have the (unsigned)DNAME + CNAME in
* that case */
cname_rrset = rrset_cache_lookup(
env->rrset_cache, qname, qnamelen,
LDNS_RR_TYPE_CNAME, qclass, 0, now, 0);
if(cname_rrset) {
/* CNAME already synthesized by
* synth_dname_msg routine, so we can
* straight up return the msg */
lock_rw_unlock(&cname_rrset->entry.lock);
return msg;
}
} else {
lock_rw_unlock(&rrset->entry.lock);
}
}
/* see if we have CNAME for this domain,
* but not for DS records (which are part of the parent) */
if(!no_partial && qtype != LDNS_RR_TYPE_DS &&
(rrset=rrset_cache_lookup(env->rrset_cache, qname, qnamelen,
LDNS_RR_TYPE_CNAME, qclass, 0, now, 0))) {
uint8_t* wc = NULL;
size_t wl;
/* if the rrset is not a wildcard expansion, with wcname */
/* because, if we return that CNAME rrset on its own, it is
* missing the NSEC or NSEC3 proof */
if(!(val_rrset_wildcard(rrset, &wc, &wl) && wc != NULL)) {
struct dns_msg* msg = rrset_msg(rrset, region, now, &k);
if(msg) {
lock_rw_unlock(&rrset->entry.lock);
return msg;
}
}
lock_rw_unlock(&rrset->entry.lock);
}
/* construct DS, DNSKEY messages from rrset cache. */
if((qtype == LDNS_RR_TYPE_DS || qtype == LDNS_RR_TYPE_DNSKEY) &&
(rrset=rrset_cache_lookup(env->rrset_cache, qname, qnamelen,
qtype, qclass, 0, now, 0))) {
/* if the rrset is from the additional section, and the
* signatures have fallen off, then do not synthesize a msg
* instead, allow a full query for signed results to happen.
* Forego all rrset data from additional section, because
* some signatures may not be present and cause validation
* failure.
*/
struct packed_rrset_data *d = (struct packed_rrset_data*)
rrset->entry.data;
if(d->trust != rrset_trust_add_noAA &&
d->trust != rrset_trust_add_AA &&
(qtype == LDNS_RR_TYPE_DS ||
(d->trust != rrset_trust_auth_noAA
&& d->trust != rrset_trust_auth_AA) )) {
struct dns_msg* msg = rrset_msg(rrset, region, now, &k);
if(msg) {
lock_rw_unlock(&rrset->entry.lock);
return msg;
}
}
lock_rw_unlock(&rrset->entry.lock);
}
/* stop downwards cache search on NXDOMAIN.
* Empty nonterminals are NOERROR, so an NXDOMAIN for foo
* means bla.foo also does not exist. The DNSSEC proofs are
* the same. We search upwards for NXDOMAINs. */
if(env->cfg->harden_below_nxdomain) {
while(!dname_is_root(k.qname)) {
if(dpname && dpnamelen
&& !dname_subdomain_c(k.qname, dpname))
break; /* no synth nxdomain above the stub */
dname_remove_label(&k.qname, &k.qname_len);
h = query_info_hash(&k, flags);
e = slabhash_lookup(env->msg_cache, h, &k, 0);
if(!e && k.qtype != LDNS_RR_TYPE_A &&
env->cfg->qname_minimisation) {
k.qtype = LDNS_RR_TYPE_A;
h = query_info_hash(&k, flags);
e = slabhash_lookup(env->msg_cache, h, &k, 0);
}
if(e) {
struct reply_info* data = (struct reply_info*)e->data;
struct dns_msg* msg;
if(FLAGS_GET_RCODE(data->flags) == LDNS_RCODE_NXDOMAIN
&& data->security == sec_status_secure
&& (data->an_numrrsets == 0 ||
ntohs(data->rrsets[0]->rk.type) != LDNS_RR_TYPE_CNAME)
&& (msg=tomsg(env, &k, data, region, now, 0, scratch))) {
lock_rw_unlock(&e->lock);
msg->qinfo.qname=qname;
msg->qinfo.qname_len=qnamelen;
/* check that DNSSEC really works out */
msg->rep->security = sec_status_unchecked;
iter_scrub_nxdomain(msg);
return msg;
}
lock_rw_unlock(&e->lock);
}
k.qtype = qtype;
}
}
/* fill common RR types for ANY response to avoid requery */
if(qtype == LDNS_RR_TYPE_ANY) {
return fill_any(env, qname, qnamelen, qtype, qclass, region);
}
return NULL;
}
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, time_t qstarttime,
int is_valrec)
{
struct reply_info* rep = NULL;
if(SERVE_EXPIRED) {
/* We are serving expired records. Before caching, check if a
* useful expired record exists. */
struct msgreply_entry* e = msg_cache_lookup(env,
msgqinf->qname, msgqinf->qname_len, msgqinf->qtype,
msgqinf->qclass, flags, 0, 1);
if(e) {
struct reply_info* cached = e->entry.data;
if(cached->ttl < *env->now
&& reply_info_could_use_expired(cached, *env->now)
/* If we are validating make sure only
* validating modules can update such messages.
* In that case don't cache it and let a
* subsequent module handle the caching. For
* example, the iterator should not replace an
* expired secure answer with a fresh unchecked
* one and let the validator manage caching. */
&& cached->security != sec_status_bogus
&& (env->need_to_validate &&
msgrep->security == sec_status_unchecked)
/* Exceptions to that rule are:
* o recursions that don't need validation but
* need to update the cache for coherence
* (delegation information while iterating,
* DNSKEY and DS lookups from validator)
* o explicit RRSIG queries that are not
* validated. */
&& !is_valrec
&& msgqinf->qtype != LDNS_RR_TYPE_RRSIG) {
if((int)FLAGS_GET_RCODE(msgrep->flags) !=
LDNS_RCODE_NOERROR &&
(int)FLAGS_GET_RCODE(msgrep->flags) !=
LDNS_RCODE_NXDOMAIN) {
/* The current response has an
* erroneous rcode. Adjust norec time
* so that additional lookups are not
* performed for some time. */
verbose(VERB_ALGO, "set "
"serve-expired-norec-ttl for "
"response in cache");
cached->serve_expired_norec_ttl =
NORR_TTL + *env->now;
if(env->cfg->serve_expired_ttl_reset &&
cached->serve_expired_ttl
< *env->now +
env->cfg->serve_expired_ttl) {
/* Reset serve-expired-ttl for
* valid response in cache. */
verbose(VERB_ALGO, "reset "
"serve-expired-ttl "
"for response in cache");
cached->serve_expired_ttl =
*env->now +
env->cfg->serve_expired_ttl;
}
}
verbose(VERB_ALGO, "a validated expired entry "
"could be overwritten, skip caching "
"the new message at this stage");
lock_rw_unlock(&e->entry.lock);
return 1;
}
lock_rw_unlock(&e->entry.lock);
}
}
/* alloc, malloc properly (not in region, like msg is) */
rep = reply_info_copy(msgrep, env->alloc, NULL);
if(!rep)
return 0;
/* ttl must be relative ;i.e. 0..86400 not time(0)+86400.
* the env->now is added to message and RRsets in this routine. */
/* the leeway is used to invalidate other rrsets earlier */
if(is_referral) {
/* store rrsets */
struct rrset_ref ref;
size_t i;
for(i=0; i<rep->rrset_count; i++) {
packed_rrset_ttl_add((struct packed_rrset_data*)
rep->rrsets[i]->entry.data, *env->now);
ref.key = rep->rrsets[i];
ref.id = rep->rrsets[i]->id;
/*ignore ret: it was in the cache, ref updated */
/* no leeway for typeNS */
(void)rrset_cache_update(env->rrset_cache, &ref,
env->alloc,
((ntohs(ref.key->rk.type)==LDNS_RR_TYPE_NS
&& !pside) ? qstarttime:*env->now + leeway));
}
reply_info_delete(rep, NULL);
return 1;
} else {
/* store msg, and rrsets */
struct query_info qinf;
hashvalue_type h;
qinf = *msgqinf;
qinf.qname = memdup(msgqinf->qname, msgqinf->qname_len);
if(!qinf.qname) {
reply_info_parsedelete(rep, env->alloc);
return 0;
}
/* fixup flags to be sensible for a reply based on the cache */
/* this module means that RA is available. It is an answer QR.
* Not AA from cache. Not CD in cache (depends on client bit). */
rep->flags |= (BIT_RA | BIT_QR);
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, 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);
}
return 1;
}
