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authorTom Gundersen <teg@jklm.no>2015-12-11 18:38:14 +0100
committerTom Gundersen <teg@jklm.no>2015-12-11 18:38:14 +0100
commita0361331758dbdb2375d6f871bc959116b699e31 (patch)
tree5a874c08bd80fc886c9481e59037df246a87c0f8
parentc57d67f718077aadee4e2d0940fb87f513b98671 (diff)
parent29c1519ed4899d139fa7b2079311cff6c4fb64a8 (diff)
Merge pull request #2143 from poettering/dnssec4
Another batch of DNSSEC fixes
-rw-r--r--src/resolve/dns-type.c43
-rw-r--r--src/resolve/dns-type.h5
-rw-r--r--src/resolve/resolved-bus.c3
-rw-r--r--src/resolve/resolved-dns-answer.c16
-rw-r--r--src/resolve/resolved-dns-cache.c8
-rw-r--r--src/resolve/resolved-dns-dnssec.c66
-rw-r--r--src/resolve/resolved-dns-dnssec.h10
-rw-r--r--src/resolve/resolved-dns-packet.c26
-rw-r--r--src/resolve/resolved-dns-transaction.c169
-rw-r--r--src/resolve/resolved-dns-transaction.h1
10 files changed, 238 insertions, 109 deletions
diff --git a/src/resolve/dns-type.c b/src/resolve/dns-type.c
index a626ecf01a..8281da3b7c 100644
--- a/src/resolve/dns-type.c
+++ b/src/resolve/dns-type.c
@@ -44,7 +44,44 @@ int dns_type_from_string(const char *s) {
return sc->id;
}
-/* XXX: find an authoritative list of all pseudo types? */
-bool dns_type_is_pseudo(uint16_t n) {
- return IN_SET(n, DNS_TYPE_ANY, DNS_TYPE_AXFR, DNS_TYPE_IXFR, DNS_TYPE_OPT);
+bool dns_type_is_pseudo(uint16_t type) {
+
+ /* Checks whether the specified type is a "pseudo-type". What
+ * a "pseudo-type" precisely is, is defined only very weakly,
+ * but apparently entails all RR types that are not actually
+ * stored as RRs on the server and should hence also not be
+ * cached. We use this list primarily to validate NSEC type
+ * bitfields, and to verify what to cache. */
+
+ return IN_SET(type,
+ 0, /* A Pseudo RR type, according to RFC 2931 */
+ DNS_TYPE_ANY,
+ DNS_TYPE_AXFR,
+ DNS_TYPE_IXFR,
+ DNS_TYPE_OPT,
+ DNS_TYPE_TSIG,
+ DNS_TYPE_TKEY
+ );
+}
+
+bool dns_type_is_valid_query(uint16_t type) {
+
+ /* The types valid as questions in packets */
+
+ return !IN_SET(type,
+ 0,
+ DNS_TYPE_OPT,
+ DNS_TYPE_TSIG,
+ DNS_TYPE_TKEY);
+}
+
+bool dns_type_is_valid_rr(uint16_t type) {
+
+ /* The types valid as RR in packets (but not necessarily
+ * stored on servers). */
+
+ return !IN_SET(type,
+ DNS_TYPE_ANY,
+ DNS_TYPE_AXFR,
+ DNS_TYPE_IXFR);
}
diff --git a/src/resolve/dns-type.h b/src/resolve/dns-type.h
index 2868025ad7..038a0d0e54 100644
--- a/src/resolve/dns-type.h
+++ b/src/resolve/dns-type.h
@@ -25,7 +25,10 @@
const char *dns_type_to_string(int type);
int dns_type_from_string(const char *s);
-bool dns_type_is_pseudo(uint16_t n);
+
+bool dns_type_is_pseudo(uint16_t type);
+bool dns_type_is_valid_query(uint16_t type);
+bool dns_type_is_valid_rr(uint16_t type);
/* DNS record types, taken from
* http://www.iana.org/assignments/dns-parameters/dns-parameters.xhtml.
diff --git a/src/resolve/resolved-bus.c b/src/resolve/resolved-bus.c
index 1427638233..c8c0d3d9b8 100644
--- a/src/resolve/resolved-bus.c
+++ b/src/resolve/resolved-bus.c
@@ -553,6 +553,9 @@ static int bus_method_resolve_record(sd_bus_message *message, void *userdata, sd
if (r == 0)
return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid name '%s'", name);
+ if (!dns_type_is_valid_query(type))
+ return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid RR type for query %" PRIu16, type);
+
r = check_ifindex_flags(ifindex, &flags, 0, error);
if (r < 0)
return r;
diff --git a/src/resolve/resolved-dns-answer.c b/src/resolve/resolved-dns-answer.c
index 55e6ffbad7..6a37345e7e 100644
--- a/src/resolve/resolved-dns-answer.c
+++ b/src/resolve/resolved-dns-answer.c
@@ -228,9 +228,9 @@ int dns_answer_contains_rr(DnsAnswer *a, DnsResourceRecord *rr) {
int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) {
DnsResourceRecord *rr;
+ int r;
assert(key);
- assert(ret);
if (!a)
return 0;
@@ -240,8 +240,12 @@ int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceReco
return 0;
DNS_ANSWER_FOREACH(rr, a) {
- if (dns_resource_key_match_soa(key, rr->key)) {
- *ret = rr;
+ r = dns_resource_key_match_soa(key, rr->key);
+ if (r < 0)
+ return r;
+ if (r > 0) {
+ if (ret)
+ *ret = rr;
return 1;
}
}
@@ -251,6 +255,7 @@ int dns_answer_find_soa(DnsAnswer *a, const DnsResourceKey *key, DnsResourceReco
int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsResourceRecord **ret) {
DnsResourceRecord *rr;
+ int r;
assert(key);
@@ -262,7 +267,10 @@ int dns_answer_find_cname_or_dname(DnsAnswer *a, const DnsResourceKey *key, DnsR
return 0;
DNS_ANSWER_FOREACH(rr, a) {
- if (dns_resource_key_match_cname_or_dname(key, rr->key, NULL)) {
+ r = dns_resource_key_match_cname_or_dname(key, rr->key, NULL);
+ if (r < 0)
+ return r;
+ if (r > 0) {
if (ret)
*ret = rr;
return 1;
diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c
index 9ab44400bd..676fa08ffb 100644
--- a/src/resolve/resolved-dns-cache.c
+++ b/src/resolve/resolved-dns-cache.c
@@ -302,7 +302,7 @@ static int dns_cache_put_positive(
if (rr->key->class == DNS_CLASS_ANY)
return 0;
- if (rr->key->type == DNS_TYPE_ANY)
+ if (dns_type_is_pseudo(rr->key->type))
return 0;
/* Entry exists already? Update TTL and timestamp */
@@ -370,9 +370,9 @@ static int dns_cache_put_negative(
if (key->class == DNS_CLASS_ANY)
return 0;
- if (key->type == DNS_TYPE_ANY)
- /* This is particularly important to filter out as we use this as a
- * pseudo-type for NXDOMAIN entries */
+ if (dns_type_is_pseudo(key->type))
+ /* ANY is particularly important to filter out as we
+ * use this as a pseudo-type for NXDOMAIN entries */
return 0;
if (soa_ttl <= 0) {
if (log_get_max_level() >= LOG_DEBUG) {
diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c
index df12e86167..792c9d8692 100644
--- a/src/resolve/resolved-dns-dnssec.c
+++ b/src/resolve/resolved-dns-dnssec.c
@@ -295,8 +295,10 @@ int dnssec_verify_rrset(
* using the signature "rrsig" and the key "dnskey". It's
* assumed the RRSIG and DNSKEY match. */
- if (!dnssec_algorithm_supported(rrsig->rrsig.algorithm))
- return -EOPNOTSUPP;
+ if (!dnssec_algorithm_supported(rrsig->rrsig.algorithm)) {
+ *result = DNSSEC_UNSUPPORTED_ALGORITHM;
+ return 0;
+ }
if (a->n_rrs > VERIFY_RRS_MAX)
return -E2BIG;
@@ -508,7 +510,7 @@ int dnssec_verify_rrset_search(
usec_t realtime,
DnssecResult *result) {
- bool found_rrsig = false, found_dnskey = false;
+ bool found_rrsig = false, found_invalid = false, found_expired_rrsig = false, found_unsupported_algorithm = false;
DnsResourceRecord *rrsig;
int r;
@@ -524,6 +526,7 @@ int dnssec_verify_rrset_search(
DNS_ANSWER_FOREACH(rrsig, a) {
DnsResourceRecord *dnskey;
+ /* Is this an RRSIG RR that applies to RRs matching our key? */
r = dnssec_key_match_rrsig(key, rrsig);
if (r < 0)
return r;
@@ -536,14 +539,13 @@ int dnssec_verify_rrset_search(
DNS_ANSWER_FOREACH(dnskey, validated_dnskeys) {
DnssecResult one_result;
+ /* Is this a DNSKEY RR that matches they key of our RRSIG? */
r = dnssec_rrsig_match_dnskey(rrsig, dnskey);
if (r < 0)
return r;
if (r == 0)
continue;
- found_dnskey = true;
-
/* Take the time here, if it isn't set yet, so
* that we do all validations with the same
* time. */
@@ -556,22 +558,53 @@ int dnssec_verify_rrset_search(
* combination. */
r = dnssec_verify_rrset(a, key, rrsig, dnskey, realtime, &one_result);
- if (r < 0 && r != EOPNOTSUPP)
+ if (r < 0)
return r;
- if (one_result == DNSSEC_VALIDATED) {
+
+ switch (one_result) {
+
+ case DNSSEC_VALIDATED:
+ /* Yay, the RR has been validated,
+ * return immediately. */
*result = DNSSEC_VALIDATED;
return 0;
- }
- /* If the signature is invalid, or done using
- an unsupported algorithm, let's try another
- key and/or signature. After all they
- key_tags and stuff are not unique, and
- might be shared by multiple keys. */
+ case DNSSEC_INVALID:
+ /* If the signature is invalid, let's try another
+ key and/or signature. After all they
+ key_tags and stuff are not unique, and
+ might be shared by multiple keys. */
+ found_invalid = true;
+ continue;
+
+ case DNSSEC_UNSUPPORTED_ALGORITHM:
+ /* If the key algorithm is
+ unsupported, try another
+ RRSIG/DNSKEY pair, but remember we
+ encountered this, so that we can
+ return a proper error when we
+ encounter nothing better. */
+ found_unsupported_algorithm = true;
+ continue;
+
+ case DNSSEC_SIGNATURE_EXPIRED:
+ /* If the signature is expired, try
+ another one, but remember it, so
+ that we can return this */
+ found_expired_rrsig = true;
+ continue;
+
+ default:
+ assert_not_reached("Unexpected DNSSEC validation result");
+ }
}
}
- if (found_dnskey)
+ if (found_expired_rrsig)
+ *result = DNSSEC_SIGNATURE_EXPIRED;
+ else if (found_unsupported_algorithm)
+ *result = DNSSEC_UNSUPPORTED_ALGORITHM;
+ else if (found_invalid)
*result = DNSSEC_INVALID;
else if (found_rrsig)
*result = DNSSEC_MISSING_KEY;
@@ -756,10 +789,11 @@ DEFINE_STRING_TABLE_LOOKUP(dnssec_mode, DnssecMode);
static const char* const dnssec_result_table[_DNSSEC_RESULT_MAX] = {
[DNSSEC_VALIDATED] = "validated",
[DNSSEC_INVALID] = "invalid",
- [DNSSEC_UNSIGNED] = "unsigned",
+ [DNSSEC_SIGNATURE_EXPIRED] = "signature-expired",
+ [DNSSEC_UNSUPPORTED_ALGORITHM] = "unsupported-algorithm",
[DNSSEC_NO_SIGNATURE] = "no-signature",
[DNSSEC_MISSING_KEY] = "missing-key",
- [DNSSEC_SIGNATURE_EXPIRED] = "signature-expired",
+ [DNSSEC_UNSIGNED] = "unsigned",
[DNSSEC_FAILED_AUXILIARY] = "failed-auxiliary",
};
DEFINE_STRING_TABLE_LOOKUP(dnssec_result, DnssecResult);
diff --git a/src/resolve/resolved-dns-dnssec.h b/src/resolve/resolved-dns-dnssec.h
index f0825ba23f..f33abe3e11 100644
--- a/src/resolve/resolved-dns-dnssec.h
+++ b/src/resolve/resolved-dns-dnssec.h
@@ -43,12 +43,18 @@ enum DnssecMode {
};
enum DnssecResult {
+ /* These four are returned by dnssec_verify_rrset() */
DNSSEC_VALIDATED,
DNSSEC_INVALID,
- DNSSEC_UNSIGNED,
+ DNSSEC_SIGNATURE_EXPIRED,
+ DNSSEC_UNSUPPORTED_ALGORITHM,
+
+ /* These two are added by dnssec_verify_rrset_search() */
DNSSEC_NO_SIGNATURE,
DNSSEC_MISSING_KEY,
- DNSSEC_SIGNATURE_EXPIRED,
+
+ /* These two are added by the DnsTransaction logic */
+ DNSSEC_UNSIGNED,
DNSSEC_FAILED_AUXILIARY,
_DNSSEC_RESULT_MAX,
_DNSSEC_RESULT_INVALID = -1
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index e90500ce70..4e069ab4cb 100644
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -171,8 +171,7 @@ DnsPacket *dns_packet_unref(DnsPacket *p) {
assert(p->n_ref > 0);
- if (p->more)
- dns_packet_unref(p->more);
+ dns_packet_unref(p->more);
if (p->n_ref == 1)
dns_packet_free(p);
@@ -1526,9 +1525,7 @@ int dns_packet_read_rr(DnsPacket *p, DnsResourceRecord **ret, size_t *start) {
goto fail;
if (key->class == DNS_CLASS_ANY ||
- key->type == DNS_TYPE_ANY ||
- key->type == DNS_TYPE_AXFR ||
- key->type == DNS_TYPE_IXFR) {
+ !dns_type_is_valid_rr(key->type)) {
r = -EBADMSG;
goto fail;
}
@@ -1972,6 +1969,11 @@ int dns_packet_extract(DnsPacket *p) {
if (r < 0)
goto finish;
+ if (!dns_type_is_valid_query(key->type)) {
+ r = -EBADMSG;
+ goto finish;
+ }
+
r = dns_question_add(question, key);
if (r < 0)
goto finish;
@@ -1994,8 +1996,18 @@ int dns_packet_extract(DnsPacket *p) {
goto finish;
if (rr->key->type == DNS_TYPE_OPT) {
- if (p->opt)
- return -EBADMSG;
+
+ /* The OPT RR is only valid in the Additional section */
+ if (i < DNS_PACKET_ANCOUNT(p) + DNS_PACKET_NSCOUNT(p)) {
+ r = -EBADMSG;
+ goto finish;
+ }
+
+ /* Two OPT RRs? */
+ if (p->opt) {
+ r = -EBADMSG;
+ goto finish;
+ }
p->opt = dns_resource_record_ref(rr);
} else {
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index bcf6d5c810..8b3e59a1ea 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -107,11 +107,11 @@ int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key)
assert(key);
/* Don't allow looking up invalid or pseudo RRs */
- if (IN_SET(key->type, DNS_TYPE_OPT, 0, DNS_TYPE_TSIG, DNS_TYPE_TKEY))
+ if (!dns_type_is_valid_query(key->type))
return -EINVAL;
/* We only support the IN class */
- if (key->class != DNS_CLASS_IN)
+ if (key->class != DNS_CLASS_IN && key->class != DNS_CLASS_ANY)
return -EOPNOTSUPP;
r = hashmap_ensure_allocated(&s->manager->dns_transactions, NULL);
@@ -351,6 +351,7 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
t->server = dns_server_ref(server);
t->received = dns_packet_unref(t->received);
t->answer = dns_answer_unref(t->answer);
+ t->n_answer_cacheable = 0;
t->answer_rcode = 0;
t->stream->complete = on_stream_complete;
t->stream->transaction = t;
@@ -375,8 +376,6 @@ static void dns_transaction_next_dns_server(DnsTransaction *t) {
}
static void dns_transaction_cache_answer(DnsTransaction *t) {
- unsigned n_cache;
-
assert(t);
/* For mDNS we cache whenever we get the packet, rather than
@@ -391,20 +390,11 @@ static void dns_transaction_cache_answer(DnsTransaction *t) {
if (!DNS_PACKET_SHALL_CACHE(t->received))
return;
- /* According to RFC 4795, section 2.9. only the RRs from the
- * answer section shall be cached. However, if we know the
- * message is authenticated, we might as well cache
- * everything. */
- if (t->answer_authenticated)
- n_cache = dns_answer_size(t->answer);
- else
- n_cache = DNS_PACKET_ANCOUNT(t->received);
-
dns_cache_put(&t->scope->cache,
t->key,
t->answer_rcode,
t->answer,
- n_cache,
+ t->n_answer_cacheable,
t->answer_authenticated,
0,
t->received->family,
@@ -618,6 +608,15 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
t->answer_rcode = DNS_PACKET_RCODE(p);
t->answer_authenticated = t->scope->dnssec_mode == DNSSEC_TRUST && DNS_PACKET_AD(p);
+ /* According to RFC 4795, section 2.9. only the RRs
+ * from the answer section shall be cached. However,
+ * if we know the message is authenticated, we might
+ * as well cache everything. */
+ if (t->answer_authenticated)
+ t->n_answer_cacheable = (unsigned) -1; /* everything! */
+ else
+ t->n_answer_cacheable = DNS_PACKET_ANCOUNT(t->received); /* only the answer section */
+
r = dns_transaction_request_dnssec_keys(t);
if (r < 0) {
dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);
@@ -770,6 +769,7 @@ static int dns_transaction_prepare(DnsTransaction *t, usec_t ts) {
t->start_usec = ts;
t->received = dns_packet_unref(t->received);
t->answer = dns_answer_unref(t->answer);
+ t->n_answer_cacheable = 0;
t->answer_rcode = 0;
t->answer_source = _DNS_TRANSACTION_SOURCE_INVALID;
@@ -1280,10 +1280,59 @@ void dns_transaction_notify(DnsTransaction *t, DnsTransaction *source) {
dns_transaction_process_dnssec(t);
}
+static int dns_transaction_is_primary_response(DnsTransaction *t, DnsResourceRecord *rr) {
+ int r;
+
+ assert(t);
+ assert(rr);
+
+ /* Check if the specified RR is the "primary" response,
+ * i.e. either matches the question precisely or is a
+ * CNAME/DNAME for it */
+
+ r = dns_resource_key_match_rr(t->key, rr, NULL);
+ if (r != 0)
+ return r;
+
+ r = dns_resource_key_match_cname_or_dname(t->key, rr->key, NULL);
+ if (r != 0)
+ return r;
+
+ return 0;
+}
+
+static int dns_transaction_validate_dnskey_by_ds(DnsTransaction *t) {
+ DnsResourceRecord *rr;
+ int ifindex, r;
+
+ assert(t);
+
+ /* Add all DNSKEY RRs from the answer that are validated by DS
+ * RRs from the list of validated keys to the lis of validated
+ * keys. */
+
+ DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, t->answer) {
+
+ r = dnssec_verify_dnskey_search(rr, t->validated_keys);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ continue;
+
+ /* If so, the DNSKEY is validated too. */
+ r = dns_answer_add_extend(&t->validated_keys, rr, ifindex);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
int dns_transaction_validate_dnssec(DnsTransaction *t) {
_cleanup_(dns_answer_unrefp) DnsAnswer *validated = NULL;
+ bool dnskeys_finalized = false;
DnsResourceRecord *rr;
- int ifindex, r;
+ int r;
assert(t);
@@ -1312,22 +1361,12 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
}
/* First see if there are DNSKEYs we already known a validated DS for. */
- DNS_ANSWER_FOREACH_IFINDEX(rr, ifindex, t->answer) {
-
- r = dnssec_verify_dnskey_search(rr, t->validated_keys);
- if (r < 0)
- return r;
- if (r == 0)
- continue;
-
- /* If so, the DNSKEY is validated too. */
- r = dns_answer_add_extend(&t->validated_keys, rr, ifindex);
- if (r < 0)
- return r;
- }
+ r = dns_transaction_validate_dnskey_by_ds(t);
+ if (r < 0)
+ return r;
for (;;) {
- bool changed = false, missing_key_for_transaction = false;
+ bool changed = false;
DNS_ANSWER_FOREACH(rr, t->answer) {
DnssecResult result;
@@ -1346,9 +1385,7 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
log_debug("Looking at %s: %s", rrs ? strstrip(rrs) : "???", dnssec_result_to_string(result));
}
- switch (result) {
-
- case DNSSEC_VALIDATED:
+ if (result == DNSSEC_VALIDATED) {
/* Add the validated RRset to the new list of validated RRsets */
r = dns_answer_copy_by_key(&validated, t->answer, rr->key);
@@ -1372,71 +1409,56 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
if (r < 0)
return r;
+ /* Exit the loop, we dropped something from the answer, start from the beginning */
changed = true;
break;
- case DNSSEC_INVALID:
- case DNSSEC_NO_SIGNATURE:
- case DNSSEC_SIGNATURE_EXPIRED:
-
- /* Is this the RRset that we were looking for? If so, this is fatal for the whole transaction */
- r = dns_resource_key_match_rr(t->key, rr, NULL);
- if (r < 0)
- return r;
- if (r > 0) {
- t->dnssec_result = result;
- return 0;
- }
+ } else if (dnskeys_finalized) {
+ /* If we haven't read all DNSKEYs yet
+ * a negative result of the validation
+ * is irrelevant, as there might be
+ * more DNSKEYs coming. */
- /* Is this a CNAME for a record we were looking for? If so, it's also fatal for the whole transaction */
- r = dns_resource_key_match_cname_or_dname(t->key, rr->key, NULL);
+ r = dns_transaction_is_primary_response(t, rr);
if (r < 0)
return r;
if (r > 0) {
+ /* This is a primary response
+ * to our question, and it
+ * failed validation. That's
+ * fatal. */
t->dnssec_result = result;
return 0;
}
- /* This is just something auxiliary. Just remove the RRset and continue. */
+ /* This is just some auxiliary
+ * data. Just remove the RRset and
+ * continue. */
r = dns_answer_remove_by_key(&t->answer, rr->key);
if (r < 0)
return r;
+ /* Exit the loop, we dropped something from the answer, start from the beginning */
changed = true;
break;
-
- case DNSSEC_MISSING_KEY:
- /* They key is missing? Let's continue
- * with the next iteration, maybe
- * we'll find it in an DNSKEY RRset
- * later on. */
-
- r = dns_resource_key_equal(rr->key, t->key);
- if (r < 0)
- return r;
- if (r > 0)
- missing_key_for_transaction = true;
-
- break;
-
- default:
- assert_not_reached("Unexpected DNSSEC result");
}
-
- if (changed)
- break;
}
if (changed)
continue;
- /* This didn't work either, there's no point in
- * continuing. */
- if (missing_key_for_transaction) {
- t->dnssec_result = DNSSEC_MISSING_KEY;
- return 0;
+ if (!dnskeys_finalized) {
+ /* OK, now we know we have added all DNSKEYs
+ * we possibly could to our validated
+ * list. Now run the whole thing once more,
+ * and strip everything we still cannot
+ * validate.
+ */
+ dnskeys_finalized = true;
+ continue;
}
+ /* We're done */
break;
}
@@ -1444,6 +1466,9 @@ int dns_transaction_validate_dnssec(DnsTransaction *t) {
t->answer = validated;
validated = NULL;
+ /* Everything that's now in t->answer is known to be good, hence cacheable. */
+ t->n_answer_cacheable = (unsigned) -1; /* everything! */
+
t->answer_authenticated = true;
t->dnssec_result = DNSSEC_VALIDATED;
return 1;
diff --git a/src/resolve/resolved-dns-transaction.h b/src/resolve/resolved-dns-transaction.h
index 2328e7937c..1f35a4dd8f 100644
--- a/src/resolve/resolved-dns-transaction.h
+++ b/src/resolve/resolved-dns-transaction.h
@@ -74,6 +74,7 @@ struct DnsTransaction {
DnsPacket *sent, *received;
DnsAnswer *answer;
+ unsigned n_answer_cacheable; /* Specifies how many RRs of the answer shall be cached, from the beginning */
int answer_rcode;
DnsTransactionSource answer_source;
bool answer_authenticated;