/** test dname_is_root */
static void
dname_test_isroot(void)
{
unit_show_func("util/data/dname.c", "dname_isroot");
unit_assert(dname_is_root((uint8_t*)"\000"));
unit_assert(!dname_is_root((uint8_t*)"\001a\000"));
unit_assert(!dname_is_root((uint8_t*)"\005abvcd\003com\000"));
/* malformed dname in this test, but should work */
unit_assert(!dname_is_root((uint8_t*)"\077a\000"));
unit_assert(dname_is_root((uint8_t*)"\000"));
}
int
forwards_next_root(struct iter_forwards* fwd, uint16_t* dclass)
{
struct iter_forward_zone key;
rbnode_t* n;
struct iter_forward_zone* p;
if(*dclass == 0) {
/* first root item is first item in tree */
n = rbtree_first(fwd->tree);
if(n == RBTREE_NULL)
return 0;
p = (struct iter_forward_zone*)n;
if(dname_is_root(p->name)) {
*dclass = p->dclass;
return 1;
}
/* root not first item? search for higher items */
*dclass = p->dclass + 1;
return forwards_next_root(fwd, dclass);
}
/* find class n in tree, we may get a direct hit, or if we don't
* this is the last item of the previous class so rbtree_next() takes
* us to the next root (if any) */
key.node.key = &key;
key.name = (uint8_t*)"\000";
key.namelen = 1;
key.namelabs = 0;
key.dclass = *dclass;
n = NULL;
if(rbtree_find_less_equal(fwd->tree, &key, &n)) {
/* exact */
return 1;
} else {
/* smaller element */
if(!n || n == RBTREE_NULL)
return 0; /* nothing found */
n = rbtree_next(n);
if(n == RBTREE_NULL)
return 0; /* no higher */
p = (struct iter_forward_zone*)n;
if(dname_is_root(p->name)) {
*dclass = p->dclass;
return 1;
}
/* not a root node, return next higher item */
*dclass = p->dclass+1;
return forwards_next_root(fwd, dclass);
}
}
struct key_entry_key*
key_cache_obtain(struct key_cache* kcache, uint8_t* name, size_t namelen,
uint16_t key_class, struct regional* region, uint32_t now)
{
/* keep looking until we find a nonexpired entry */
while(1) {
struct key_entry_key* k = key_cache_search(kcache, name,
namelen, key_class, 0);
if(k) {
/* see if TTL is OK */
struct key_entry_data* d = (struct key_entry_data*)
k->entry.data;
if(now <= d->ttl) {
/* copy and return it */
struct key_entry_key* retkey =
key_entry_copy_toregion(k, region);
lock_rw_unlock(&k->entry.lock);
return retkey;
}
lock_rw_unlock(&k->entry.lock);
}
/* snip off first label to continue */
if(dname_is_root(name))
break;
dname_remove_label(&name, &namelen);
}
return NULL;
}
/**
* Calculate space needed for zone and all its parents
* @param d: name of zone
* @param len: length of name
* @return size.
*/
static size_t calc_zone_need(uint8_t* d, size_t len)
{
size_t res = sizeof(struct val_neg_zone) + len;
while(!dname_is_root(d)) {
log_assert(len > 1); /* not root label */
dname_remove_label(&d, &len);
res += sizeof(struct val_neg_zone) + len;
}
return res;
}
/** delete empty terminals from tree when final data is deleted */
static void
del_empty_term(struct local_zone* z, struct local_data* d,
uint8_t* name, size_t len, int labs)
{
while(d && d->rrsets == NULL && is_terminal(d)) {
/* is this empty nonterminal? delete */
/* note, no memory recycling in zone region */
(void)rbtree_delete(&z->data, d);
/* go up and to the next label */
if(dname_is_root(name))
return;
dname_remove_label(&name, &len);
labs--;
d = lz_find_node(z, name, len, labs);
}
}
/**
* Calculate space needed for the data and all its parents
* @param rep: NSEC entries.
* @return size.
*/
static size_t calc_data_need(struct reply_info* rep)
{
uint8_t* d;
size_t i, len, res = 0;
for(i=rep->an_numrrsets; i<rep->an_numrrsets+rep->ns_numrrsets; i++) {
if(ntohs(rep->rrsets[i]->rk.type) == LDNS_RR_TYPE_NSEC) {
d = rep->rrsets[i]->rk.dname;
len = rep->rrsets[i]->rk.dname_len;
res = sizeof(struct val_neg_data) + len;
while(!dname_is_root(d)) {
log_assert(len > 1); /* not root label */
dname_remove_label(&d, &len);
res += sizeof(struct val_neg_data) + len;
}
}
}
return res;
}
/** check if negative cache is still valid */
static void check_zone_invariants(struct val_neg_cache* neg,
struct val_neg_zone* zone)
{
unit_assert(zone->nsec3_hash == 0);
unit_assert(zone->tree.cmp == &val_neg_data_compare);
unit_assert(zone->count != 0);
if(zone->tree.count == 0)
unit_assert(!zone->in_use);
else {
if(!zone->in_use) {
/* details on error */
log_nametypeclass(0, "zone", zone->name, 0, 0);
log_err("inuse %d count=%d tree.count=%d",
zone->in_use, zone->count,
(int)zone->tree.count);
if(negverbose)
print_neg_cache(neg);
}
unit_assert(zone->in_use);
}
if(zone->parent) {
unit_assert(zone->parent->count >= zone->count);
if(zone->parent->in_use) {
unit_assert(zone->parent->count > zone->count);
}
unit_assert(zone->parent->labs == zone->labs-1);
/* and parent must be one label shorter */
unit_assert(zone->name[0] == (zone->len-zone->parent->len-1));
unit_assert(query_dname_compare(zone->name + zone->name[0]+1,
zone->parent->name) == 0);
} else {
/* must be apex */
unit_assert(dname_is_root(zone->name));
}
/* tree property: */
unit_assert(zone->count == sum_zone_subtree_inuse(neg, zone));
/* check structure of zone data tree */
checkzonetree(zone);
}
/** check point in data tree */
static void check_data(struct val_neg_zone* zone, struct val_neg_data* data)
{
unit_assert(data->count > 0);
if(data->parent) {
unit_assert(data->parent->count >= data->count);
if(data->parent->in_use) {
unit_assert(data->parent->count > data->count);
}
unit_assert(data->parent->labs == data->labs-1);
/* and parent must be one label shorter */
unit_assert(data->name[0] == (data->len-data->parent->len-1));
unit_assert(query_dname_compare(data->name + data->name[0]+1,
data->parent->name) == 0);
} else {
/* must be apex */
unit_assert(dname_is_root(data->name));
}
/* tree property: */
unit_assert(data->count == sum_subtree_inuse(zone, data));
}
/**
* Initialize the filter structure.
* Finds the zone by looking at available NSEC3 records and best match.
* (skips the unknown flag and unknown algo NSEC3s).
*
* @param filter: nsec3 filter structure.
* @param list: list of rrsets, an array of them.
* @param num: number of rrsets in list.
* @param qinfo:
* query name to match a zone for.
* query type (if DS a higher zone must be chosen)
* qclass, to filter NSEC3s with.
*/
static void
filter_init(struct nsec3_filter* filter, struct ub_packed_rrset_key** list,
size_t num, struct query_info* qinfo)
{
size_t i;
uint8_t* nm;
size_t nmlen;
filter->zone = NULL;
filter->zone_len = 0;
filter->list = list;
filter->num = num;
filter->fclass = qinfo->qclass;
for(i=0; i<num; i++) {
/* ignore other stuff in the list */
if(ntohs(list[i]->rk.type) != LDNS_RR_TYPE_NSEC3 ||
ntohs(list[i]->rk.rrset_class) != qinfo->qclass)
continue;
/* skip unknown flags, algo */
if(!nsec3_rrset_has_known(list[i]))
continue;
/* since NSEC3s are base32.zonename, we can find the zone
* name by stripping off the first label of the record */
nm = list[i]->rk.dname;
nmlen = list[i]->rk.dname_len;
dname_remove_label(&nm, &nmlen);
/* if we find a domain that can prove about the qname,
* and if this domain is closer to the qname */
if(dname_subdomain_c(qinfo->qname, nm) && (!filter->zone ||
dname_subdomain_c(nm, filter->zone))) {
/* for a type DS do not accept a zone equal to qname*/
if(qinfo->qtype == LDNS_RR_TYPE_DS &&
query_dname_compare(qinfo->qname, nm) == 0 &&
!dname_is_root(qinfo->qname))
continue;
filter->zone = nm;
filter->zone_len = nmlen;
}
}
}
int print_deleg_lookup(SSL* ssl, struct worker* worker, uint8_t* nm,
size_t nmlen, int ATTR_UNUSED(nmlabs))
{
/* deep links into the iterator module */
struct delegpt* dp;
struct dns_msg* msg;
struct regional* region = worker->scratchpad;
char b[260];
struct query_info qinfo;
struct iter_hints_stub* stub;
regional_free_all(region);
qinfo.qname = nm;
qinfo.qname_len = nmlen;
qinfo.qtype = LDNS_RR_TYPE_A;
qinfo.qclass = LDNS_RR_CLASS_IN;
qinfo.local_alias = NULL;
dname_str(nm, b);
if(!ssl_printf(ssl, "The following name servers are used for lookup "
"of %s\n", b))
return 0;
dp = forwards_lookup(worker->env.fwds, nm, qinfo.qclass);
if(dp) {
if(!ssl_printf(ssl, "forwarding request:\n"))
return 0;
print_dp_main(ssl, dp, NULL);
print_dp_details(ssl, worker, dp);
return 1;
}
while(1) {
dp = dns_cache_find_delegation(&worker->env, nm, nmlen,
qinfo.qtype, qinfo.qclass, region, &msg,
*worker->env.now);
if(!dp) {
return ssl_printf(ssl, "no delegation from "
"cache; goes to configured roots\n");
}
/* go up? */
if(iter_dp_is_useless(&qinfo, BIT_RD, dp)) {
print_dp_main(ssl, dp, msg);
print_dp_details(ssl, worker, dp);
if(!ssl_printf(ssl, "cache delegation was "
"useless (no IP addresses)\n"))
return 0;
if(dname_is_root(nm)) {
/* goes to root config */
return ssl_printf(ssl, "no delegation from "
"cache; goes to configured roots\n");
} else {
/* useless, goes up */
nm = dp->name;
nmlen = dp->namelen;
dname_remove_label(&nm, &nmlen);
dname_str(nm, b);
if(!ssl_printf(ssl, "going up, lookup %s\n", b))
return 0;
continue;
}
}
stub = hints_lookup_stub(worker->env.hints, nm, qinfo.qclass,
dp);
if(stub) {
if(stub->noprime) {
if(!ssl_printf(ssl, "The noprime stub servers "
"are used:\n"))
return 0;
} else {
if(!ssl_printf(ssl, "The stub is primed "
"with servers:\n"))
return 0;
}
print_dp_main(ssl, stub->dp, NULL);
print_dp_details(ssl, worker, stub->dp);
} else {
print_dp_main(ssl, dp, msg);
print_dp_details(ssl, worker, dp);
}
break;
}
return 1;
}
/** Do the nodata proof */
static enum sec_status
nsec3_do_prove_nodata(struct module_env* env, struct nsec3_filter* flt,
rbtree_t* ct, struct query_info* qinfo)
{
struct ce_response ce;
uint8_t* wc;
size_t wclen;
struct ub_packed_rrset_key* rrset;
int rr;
enum sec_status sec;
if(find_matching_nsec3(env, flt, ct, qinfo->qname, qinfo->qname_len,
&rrset, &rr)) {
/* cases 1 and 2 */
if(nsec3_has_type(rrset, rr, qinfo->qtype)) {
verbose(VERB_ALGO, "proveNodata: Matching NSEC3 "
"proved that type existed, bogus");
return sec_status_bogus;
} else if(nsec3_has_type(rrset, rr, LDNS_RR_TYPE_CNAME)) {
verbose(VERB_ALGO, "proveNodata: Matching NSEC3 "
"proved that a CNAME existed, bogus");
return sec_status_bogus;
}
/*
* If type DS: filter_init zone find already found a parent
* zone, so this nsec3 is from a parent zone.
* o can be not a delegation (unusual query for normal name,
* no DS anyway, but we can verify that).
* o can be a delegation (which is the usual DS check).
* o may not have the SOA bit set (only the top of the
* zone, which must have been above the name, has that).
* Except for the root; which is checked by itself.
*
* If not type DS: matching nsec3 must not be a delegation.
*/
if(qinfo->qtype == LDNS_RR_TYPE_DS && qinfo->qname_len != 1
&& nsec3_has_type(rrset, rr, LDNS_RR_TYPE_SOA) &&
!dname_is_root(qinfo->qname)) {
verbose(VERB_ALGO, "proveNodata: apex NSEC3 "
"abused for no DS proof, bogus");
return sec_status_bogus;
} else if(qinfo->qtype != LDNS_RR_TYPE_DS &&
nsec3_has_type(rrset, rr, LDNS_RR_TYPE_NS) &&
!nsec3_has_type(rrset, rr, LDNS_RR_TYPE_SOA)) {
if(!nsec3_has_type(rrset, rr, LDNS_RR_TYPE_DS)) {
verbose(VERB_ALGO, "proveNodata: matching "
"NSEC3 is insecure delegation");
return sec_status_insecure;
}
verbose(VERB_ALGO, "proveNodata: matching "
"NSEC3 is a delegation, bogus");
return sec_status_bogus;
}
return sec_status_secure;
}
/* For cases 3 - 5, we need the proven closest encloser, and it
* can't match qname. Although, at this point, we know that it
* won't since we just checked that. */
sec = nsec3_prove_closest_encloser(env, flt, ct, qinfo, 1, &ce);
if(sec == sec_status_bogus) {
verbose(VERB_ALGO, "proveNodata: did not match qname, "
"nor found a proven closest encloser.");
return sec_status_bogus;
} else if(sec==sec_status_insecure && qinfo->qtype!=LDNS_RR_TYPE_DS){
verbose(VERB_ALGO, "proveNodata: closest nsec3 is insecure "
"delegation.");
return sec_status_insecure;
}
/* Case 3: removed */
/* Case 4: */
log_assert(ce.ce);
wc = nsec3_ce_wildcard(env->scratch, ce.ce, ce.ce_len, &wclen);
if(wc && find_matching_nsec3(env, flt, ct, wc, wclen, &rrset, &rr)) {
/* found wildcard */
if(nsec3_has_type(rrset, rr, qinfo->qtype)) {
verbose(VERB_ALGO, "nsec3 nodata proof: matching "
"wildcard had qtype, bogus");
return sec_status_bogus;
} else if(nsec3_has_type(rrset, rr, LDNS_RR_TYPE_CNAME)) {
verbose(VERB_ALGO, "nsec3 nodata proof: matching "
"wildcard had a CNAME, bogus");
return sec_status_bogus;
}
if(qinfo->qtype == LDNS_RR_TYPE_DS && qinfo->qname_len != 1
&& nsec3_has_type(rrset, rr, LDNS_RR_TYPE_SOA)) {
verbose(VERB_ALGO, "nsec3 nodata proof: matching "
"wildcard for no DS proof has a SOA, bogus");
return sec_status_bogus;
} else if(qinfo->qtype != LDNS_RR_TYPE_DS &&
nsec3_has_type(rrset, rr, LDNS_RR_TYPE_NS) &&
!nsec3_has_type(rrset, rr, LDNS_RR_TYPE_SOA)) {
verbose(VERB_ALGO, "nsec3 nodata proof: matching "
"wilcard is a delegation, bogus");
return sec_status_bogus;
}
/* everything is peachy keen, except for optout spans */
if(ce.nc_rrset && nsec3_has_optout(ce.nc_rrset, ce.nc_rr)) {
verbose(VERB_ALGO, "nsec3 nodata proof: matching "
"wildcard is in optout range, insecure");
return sec_status_insecure;
}
return sec_status_secure;
}
/* Case 5: */
/* Due to forwarders, cnames, and other collating effects, we
* can see the ordinary unsigned data from a zone beneath an
* insecure delegation under an optout here */
if(!ce.nc_rrset) {
verbose(VERB_ALGO, "nsec3 nodata proof: no next closer nsec3");
return sec_status_bogus;
}
/* We need to make sure that the covering NSEC3 is opt-out. */
log_assert(ce.nc_rrset);
if(!nsec3_has_optout(ce.nc_rrset, ce.nc_rr)) {
if(qinfo->qtype == LDNS_RR_TYPE_DS)
verbose(VERB_ALGO, "proveNodata: covering NSEC3 was not "
"opt-out in an opt-out DS NOERROR/NODATA case.");
else verbose(VERB_ALGO, "proveNodata: could not find matching "
"NSEC3, nor matching wildcard, nor optout NSEC3 "
"-- no more options, bogus.");
return sec_status_bogus;
}
/* RFC5155 section 9.2: if nc has optout then no AD flag set */
return sec_status_insecure;
}
struct dns_msg*
dns_cache_lookup(struct module_env* env,
uint8_t* qname, size_t qnamelen, uint16_t qtype, uint16_t qclass,
uint16_t flags, struct regional* region, struct regional* scratch,
int no_partial)
{
struct lruhash_entry* e;
struct query_info k;
hashvalue_type h;
time_t now = *env->now;
struct ub_packed_rrset_key* rrset;
/* 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,
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))) {
/* 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, DLV messages from rrset cache. */
if((qtype == LDNS_RR_TYPE_DS || qtype == LDNS_RR_TYPE_DNSKEY ||
qtype == LDNS_RR_TYPE_DLV) &&
(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)) {
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
&& (msg=tomsg(env, &k, data, region, now, 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;
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;
}
struct dns_msg*
dns_cache_lookup(struct module_env* env,
uint8_t* qname, size_t qnamelen, uint16_t qtype, uint16_t qclass,
uint16_t flags, struct regional* region, struct regional* scratch)
{
struct lruhash_entry* e;
struct query_info k;
hashvalue_t h;
time_t now = *env->now;
struct ub_packed_rrset_key* rrset;
/* lookup first, this has both NXdomains and ANSWER responses */
k.qname = qname;
k.qname_len = qnamelen;
k.qtype = qtype;
k.qclass = qclass;
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,
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( (rrset=find_closest_of_type(env, qname, qnamelen, qclass, now,
LDNS_RR_TYPE_DNAME, 1))) {
/* synthesize a DNAME+CNAME message based on this */
struct dns_msg* msg = synth_dname_msg(rrset, region, now, &k);
if(msg) {
lock_rw_unlock(&rrset->entry.lock);
return msg;
}
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( qtype != LDNS_RR_TYPE_DS &&
(rrset=rrset_cache_lookup(env->rrset_cache, qname, qnamelen,
LDNS_RR_TYPE_CNAME, qclass, 0, now, 0))) {
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, DLV messages from rrset cache. */
if((qtype == LDNS_RR_TYPE_DS || qtype == LDNS_RR_TYPE_DNSKEY ||
qtype == LDNS_RR_TYPE_DLV) &&
(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)) {
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) {
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
&& (msg=tomsg(env, &k, data, region, now, 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;
return msg;
}
lock_rw_unlock(&e->lock);
}
}
return NULL;
}
