f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering#include "af-list.h"

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering#include "alloc-util.h"

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering#include "dns-domain.h"

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering#include "fd-util.h"

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering#include "random-util.h"

4f5dd3943bef8a04be7e3b838b822bb9a7ad6cb3Lennart Poettering#include "resolved-dns-transaction.h"

a5c32cff1f56afe6f0c6c70d91a88a7a8238b2d7Harald Hoyer#include "resolved-llmnr.h"

6482f6269c87d2249e52e889a63adbdd50f2d691Ronny Chevalier#include "string-table.h"

4f5dd3943bef8a04be7e3b838b822bb9a7ad6cb3Lennart Poettering

07630cea1f3a845c09309f197ac7c4f11edd3b62Lennart PoetteringDnsTransaction* dns_transaction_free(DnsTransaction *t) {

4f5dd3943bef8a04be7e3b838b822bb9a7ad6cb3Lennart Poettering DnsQueryCandidate *c;

4f5dd3943bef8a04be7e3b838b822bb9a7ad6cb3Lennart Poettering DnsZoneItem *i;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (!t)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering sd_event_source_unref(t->timeout_event_source);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_packet_unref(t->sent);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_packet_unref(t->received);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_answer_unref(t->answer);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering sd_event_source_unref(t->dns_udp_event_source);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering safe_close(t->dns_udp_fd);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_server_unref(t->server);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_stream_free(t->stream);

2b6bf07dd23bb467099d213c97b3875c5e453491Zbigniew Jędrzejewski-Szmek

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (t->scope) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering hashmap_remove(t->scope->transactions, t->key);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (t->id != 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering hashmap_remove(t->scope->manager->dns_transactions, UINT_TO_PTR(t->id));

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_resource_key_unref(t->key);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering while ((c = set_steal_first(t->query_candidates)))

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering set_remove(c->transactions, t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering set_free(t->query_candidates);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering while ((i = set_steal_first(t->zone_items)))

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering i->probe_transaction = NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering set_free(t->zone_items);

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering free(t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return NULL;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering}

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart PoetteringDEFINE_TRIVIAL_CLEANUP_FUNC(DnsTransaction*, dns_transaction_free);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringvoid dns_transaction_gc(DnsTransaction *t) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (t->block_gc > 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (set_isempty(t->query_candidates) && set_isempty(t->zone_items))

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_transaction_free(t);

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering}

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringint dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering _cleanup_(dns_transaction_freep) DnsTransaction *t = NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering int r;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

d2e54fae5ca7a0f71b5ac8b356a589ff0a09ea0aKay Sievers assert(ret);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(s);

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering assert(key);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = hashmap_ensure_allocated(&s->manager->dns_transactions, NULL);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0)

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering return r;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = hashmap_ensure_allocated(&s->transactions, &dns_resource_key_hash_ops);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return r;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t = new0(DnsTransaction, 1);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering if (!t)

90b2de37b80603168f4e9c9c81cff7eea4efa21aZbigniew Jędrzejewski-Szmek return -ENOMEM;

90b2de37b80603168f4e9c9c81cff7eea4efa21aZbigniew Jędrzejewski-Szmek

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->dns_udp_fd = -1;

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering t->key = dns_resource_key_ref(key);

90b2de37b80603168f4e9c9c81cff7eea4efa21aZbigniew Jędrzejewski-Szmek

90b2de37b80603168f4e9c9c81cff7eea4efa21aZbigniew Jędrzejewski-Szmek /* Find a fresh, unused transaction id */

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering do

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering random_bytes(&t->id, sizeof(t->id));

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering while (t->id == 0 ||

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering hashmap_get(s->manager->dns_transactions, UINT_TO_PTR(t->id)));

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen r = hashmap_put(s->manager->dns_transactions, UINT_TO_PTR(t->id), t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0) {

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen t->id = 0;

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen return r;

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen }

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = hashmap_put(s->transactions, t->key, t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering hashmap_remove(s->manager->dns_transactions, UINT_TO_PTR(t->id));

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering return r;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen t->scope = s;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen if (ret)

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen *ret = t;

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen

88231eb62cafc8bb51406919c8cf6019dc1ac916Thomas Hindoe Paaboel Andersen t = NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return 0;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringstatic void dns_transaction_stop(DnsTransaction *t) {

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering assert(t);

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering t->timeout_event_source = sd_event_source_unref(t->timeout_event_source);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->stream = dns_stream_free(t->stream);

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* Note that we do not drop the UDP socket here, as we want to

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poetteringstatic void dns_transaction_tentative(DnsTransaction *t, DnsPacket *p) {

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering _cleanup_free_ char *pretty = NULL;

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering DnsZoneItem *z;

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering assert(t);

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering assert(p);

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (manager_our_packet(t->scope->manager, p) != 0)

dacd6cee76a08331b8c8616c5f30f70ee49aa2f9Lennart Poettering return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering in_addr_to_string(p->family, &p->sender, &pretty);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering log_debug("Transaction on scope %s on %s/%s got tentative packet from %s",

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_protocol_to_string(t->scope->protocol),

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->scope->link ? t->scope->link->name : "*",

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->scope->family == AF_UNSPEC ? "*" : af_to_name(t->scope->family),

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering pretty);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering /* RFC 4795, Section 4.1 says that the peer with the

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (memcmp(&p->sender, &p->destination, FAMILY_ADDRESS_SIZE(p->family)) >= 0) {

de0671ee7fe465e108f62dcbbbe9366f81dd9e9aZbigniew Jędrzejewski-Szmek log_debug("Peer has lexicographically larger IP address and thus lost in the conflict.");

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering log_debug("We have the lexicographically larger IP address and thus lost in the conflict.");

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->block_gc++;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering while ((z = set_first(t->zone_items))) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* First, make sure the zone item drops the reference

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_zone_item_probe_stop(z);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* Secondly, report this as conflict, so that we might

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_zone_item_conflict(z);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

de0671ee7fe465e108f62dcbbbe9366f81dd9e9aZbigniew Jędrzejewski-Szmek t->block_gc--;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

de0671ee7fe465e108f62dcbbbe9366f81dd9e9aZbigniew Jędrzejewski-Szmek dns_transaction_gc(t);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringvoid dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering DnsQueryCandidate *c;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering DnsZoneItem *z;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering Iterator i;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering assert(t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(!IN_SET(state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING));

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* Note that this call might invalidate the query. Callers

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering log_debug("Transaction on scope %s on %s/%s now complete with <%s>",

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_protocol_to_string(t->scope->protocol),

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->scope->link ? t->scope->link->name : "*",

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->scope->family == AF_UNSPEC ? "*" : af_to_name(t->scope->family),

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_transaction_state_to_string(state));

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering t->state = state;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering dns_transaction_stop(t);

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering /* Notify all queries that are interested, but make sure the

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering t->block_gc++;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering SET_FOREACH(c, t->query_candidates, i)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_query_candidate_ready(c);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering SET_FOREACH(z, t->zone_items, i)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_zone_item_ready(z);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->block_gc--;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering dns_transaction_gc(t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringstatic int on_stream_complete(DnsStream *s, int error) {

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering DnsTransaction *t;

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(s);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(s->transaction);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering /* Copy the data we care about out of the stream before we

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering t = s->transaction;

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering p = dns_packet_ref(s->read_packet);

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn t->stream = dns_stream_free(t->stream);

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering if (error != 0) {

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering return 0;

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn }

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn if (dns_packet_validate_reply(p) <= 0) {

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering log_debug("Invalid LLMNR TCP packet.");

a34faf579d2be139b0b9e8cd0c73ad4d918ef736Lukas Nykryn dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return 0;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering dns_scope_check_conflicts(t->scope, p);

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->block_gc++;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_transaction_process_reply(t, p);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->block_gc--;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* If the response wasn't useful, then complete the transition now */

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (t->state == DNS_TRANSACTION_PENDING)

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering

527b7a421ff3927d4f3f170b1b143452e88ae1dcLennart Poettering return 0;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringstatic int dns_transaction_open_tcp(DnsTransaction *t) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering DnsServer *server = NULL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering _cleanup_close_ int fd = -1;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering int r;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

03e334a1c7dc8c20c38902aa039440763acc9b17Lennart Poettering if (t->stream)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return 0;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering switch (t->scope->protocol) {

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering case DNS_PROTOCOL_DNS:

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering fd = dns_scope_tcp_socket(t->scope, AF_UNSPEC, NULL, 53, &server);

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering break;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering case DNS_PROTOCOL_LLMNR:

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering /* When we already received a reply to this (but it was truncated), send to its sender address */

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering if (t->received)

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering fd = dns_scope_tcp_socket(t->scope, t->received->family, &t->received->sender, t->received->sender_port, NULL);

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering else {

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering union in_addr_union address;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering int family = AF_UNSPEC;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering /* Otherwise, try to talk to the owner of a

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = dns_name_address(DNS_RESOURCE_KEY_NAME(t->key), &family, &address);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return r;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r == 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return -EINVAL;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (family != t->scope->family)

d2e54fae5ca7a0f71b5ac8b356a589ff0a09ea0aKay Sievers return -ESRCH;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering fd = dns_scope_tcp_socket(t->scope, family, &address, LLMNR_PORT, NULL);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering break;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering default:

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return -EAFNOSUPPORT;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (fd < 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return fd;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = dns_stream_new(t->scope->manager, &t->stream, t->scope->protocol, fd);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return r;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering fd = -1;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

151b9b9662a90455262ce575a8a8ae74bf4ff336Lennart Poettering r = dns_stream_write_packet(t->stream, t->sent);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (r < 0) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->stream = dns_stream_free(t->stream);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return r;

718db96199eb307751264e4163555662c9a389faLennart Poettering }

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering dns_server_unref(t->server);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->server = dns_server_ref(server);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->received = dns_packet_unref(t->received);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->answer = dns_answer_unref(t->answer);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->answer_rcode = 0;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->stream->complete = on_stream_complete;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->stream->transaction = t;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* The interface index is difficult to determine if we are

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering if (t->scope->link)

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->stream->ifindex = t->scope->link->ifindex;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

03e334a1c7dc8c20c38902aa039440763acc9b17Lennart Poettering return 0;

03e334a1c7dc8c20c38902aa039440763acc9b17Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringstatic void dns_transaction_next_dns_server(DnsTransaction *t) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t);

a1e58e8ee1c84b633d6d6d651d5328d4dd4eba5bLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->server = dns_server_unref(t->server);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->dns_udp_event_source = sd_event_source_unref(t->dns_udp_event_source);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering t->dns_udp_fd = safe_close(t->dns_udp_fd);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_scope_next_dns_server(t->scope);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering}

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poetteringvoid dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering usec_t ts;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering int r;

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering assert(t);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering assert(p);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t->state == DNS_TRANSACTION_PENDING);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t->scope);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering assert(t->scope->manager);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* Note that this call might invalidate the query. Callers

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering switch (t->scope->protocol) {

2c4f86c1298f402220965682ab0e7729e150a562Lennart Poettering case DNS_PROTOCOL_LLMNR:

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering assert(t->scope->link);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

2c4f86c1298f402220965682ab0e7729e150a562Lennart Poettering /* For LLMNR we will not accept any packets from other

2c4f86c1298f402220965682ab0e7729e150a562Lennart Poettering

2c4f86c1298f402220965682ab0e7729e150a562Lennart Poettering if (p->ifindex != t->scope->link->ifindex)

2c4f86c1298f402220965682ab0e7729e150a562Lennart Poettering return;

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (p->family != t->scope->family)

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering return;

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* Tentative packets are not full responses but still

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (DNS_PACKET_LLMNR_T(p)) {

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering dns_transaction_tentative(t, p);

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering return;

85a428c69465b047731b6abb5005f01824f1444eLennart Poettering }

85a428c69465b047731b6abb5005f01824f1444eLennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering break;

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering case DNS_PROTOCOL_DNS:

5cb14b3742038b28551b161635a0cba3559404b2Lennart Poettering break;

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering default:

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering assert_not_reached("Invalid DNS protocol.");

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering }

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

cc3773810855956bad92337cee8fa193584ab62eLennart Poettering if (t->received != p) {

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering dns_packet_unref(t->received);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering t->received = dns_packet_ref(p);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering }

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering if (p->ipproto == IPPROTO_TCP) {

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering if (DNS_PACKET_TC(p)) {

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering /* Truncated via TCP? Somebody must be fucking with us */

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering return;

409133be63387fc04d927e8aecd2f6ba03d2f143Lennart Poettering }

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (DNS_PACKET_ID(p) != t->id) {

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering /* Not the reply to our query? Somebody must be fucking with us */

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering return;

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering }

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering }

85a428c69465b047731b6abb5005f01824f1444eLennart Poettering

85a428c69465b047731b6abb5005f01824f1444eLennart Poettering assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);

85a428c69465b047731b6abb5005f01824f1444eLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering switch (t->scope->protocol) {

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering case DNS_PROTOCOL_DNS:

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering assert(t->server);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering dns_server_packet_received(t->server, ts - t->start_usec);

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering break;

c7b5eb98e8eeafe63a079ee3c51e9670872437aeLennart Poettering case DNS_PROTOCOL_LLMNR:

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering case DNS_PROTOCOL_MDNS:

ec202eae8e84a4c99f054f771cb832046cb8769fShawn Landden dns_scope_packet_received(t->scope, ts - t->start_usec);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering break;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering default:

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering break;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (DNS_PACKET_TC(p)) {

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* Response was truncated, let's try again with good old TCP */

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering r = dns_transaction_open_tcp(t);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (r == -ESRCH) {

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* No servers found? Damn! */

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering return;

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering }

8e7fd6ade44ce5dde0867ba748c7978ed1206865Lennart Poettering if (r < 0) {

8e7fd6ade44ce5dde0867ba748c7978ed1206865Lennart Poettering /* On LLMNR, if we cannot connect to the host,

8e7fd6ade44ce5dde0867ba748c7978ed1206865Lennart Poettering if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering return;

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering }

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* On DNS, couldn't send? Try immediately again, with a new server */

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering dns_transaction_next_dns_server(t);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering r = dns_transaction_go(t);

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (r < 0) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek /* Parse and update the cache */

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering r = dns_packet_extract(p);

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek if (r < 0) {

4943c1c94ba751c98763f4232b4350481b22c90aLennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering /* Install the answer as answer to the transaction */

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek dns_answer_unref(t->answer);

8e7fd6ade44ce5dde0867ba748c7978ed1206865Lennart Poettering t->answer = dns_answer_ref(p->answer);

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek t->answer_rcode = DNS_PACKET_RCODE(p);

8e7fd6ade44ce5dde0867ba748c7978ed1206865Lennart Poettering

a2a5291b3f5ab6ed4c92f51d0fd10a03047380d8Zbigniew Jędrzejewski-Szmek /* Only consider responses with equivalent query section to the request */

beaafb2ea6be591882aef21fe19b88e3b2461087Lennart Poettering if (p->question->n_keys != 1 || dns_resource_key_equal(p->question->keys[0], t->key) <= 0) {

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering return;

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering }

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering /* According to RFC 4795, section 2.9. only the RRs from the answer section shall be cached */

f8e2fb7b14e53f5a4bcfd66d26910af1dee185c6Lennart Poettering dns_cache_put(&t->scope->cache, t->key, DNS_PACKET_RCODE(p), p->answer, DNS_PACKET_ANCOUNT(p), 0, p->family, &p->sender);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering if (DNS_PACKET_RCODE(p) == DNS_RCODE_SUCCESS)

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering else

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering dns_transaction_complete(t, DNS_TRANSACTION_FAILURE);

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering}

eecd1362f7f4de432483b5d77c56726c3621a83aLennart Poettering

static int on_dns_packet(sd_event_source *s, int fd, uint32_t revents, void *userdata) {

_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;

DnsTransaction *t = userdata;

int r;

assert(t);

assert(t->scope);

r = manager_recv(t->scope->manager, fd, DNS_PROTOCOL_DNS, &p);

if (r <= 0)

return r;

if (dns_packet_validate_reply(p) > 0 &&

DNS_PACKET_ID(p) == t->id)

dns_transaction_process_reply(t, p);

else

log_debug("Invalid DNS packet.");

return 0;

}

static int dns_transaction_emit(DnsTransaction *t) {

int r;

assert(t);

if (t->scope->protocol == DNS_PROTOCOL_DNS && !t->server) {

DnsServer *server = NULL;

_cleanup_close_ int fd = -1;

fd = dns_scope_udp_dns_socket(t->scope, &server);

if (fd < 0)

return fd;

r = sd_event_add_io(t->scope->manager->event, &t->dns_udp_event_source, fd, EPOLLIN, on_dns_packet, t);

if (r < 0)

return r;

t->dns_udp_fd = fd;

fd = -1;

t->server = dns_server_ref(server);

}

r = dns_scope_emit(t->scope, t->dns_udp_fd, t->sent);

if (r < 0)

return r;

return 0;

}

static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdata) {

DnsTransaction *t = userdata;

int r;

assert(s);

assert(t);

/* Timeout reached? Try again, with a new server */

dns_transaction_next_dns_server(t);

/* ... and possibly increased timeout */

if (t->server)

dns_server_packet_lost(t->server, usec - t->start_usec);

else

dns_scope_packet_lost(t->scope, usec - t->start_usec);

r = dns_transaction_go(t);

if (r < 0)

dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);

return 0;

}

static int dns_transaction_make_packet(DnsTransaction *t) {

_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;

int r;

assert(t);

if (t->sent)

return 0;

r = dns_packet_new_query(&p, t->scope->protocol, 0);

if (r < 0)

return r;

r = dns_scope_good_key(t->scope, t->key);

if (r < 0)

return r;

if (r == 0)

return -EDOM;

r = dns_packet_append_key(p, t->key, NULL);

if (r < 0)

return r;

DNS_PACKET_HEADER(p)->qdcount = htobe16(1);

DNS_PACKET_HEADER(p)->id = t->id;

t->sent = p;

p = NULL;

return 0;

}

static usec_t transaction_get_resend_timeout(DnsTransaction *t) {

assert(t);

assert(t->scope);

switch (t->scope->protocol) {

case DNS_PROTOCOL_DNS:

assert(t->server);

return t->server->resend_timeout;

case DNS_PROTOCOL_LLMNR:

case DNS_PROTOCOL_MDNS:

return t->scope->resend_timeout;

default:

assert_not_reached("Invalid DNS protocol.");

}

}

int dns_transaction_go(DnsTransaction *t) {

bool had_stream;

usec_t ts;

int r;

assert(t);

had_stream = !!t->stream;

dns_transaction_stop(t);

log_debug("Excercising transaction on scope %s on %s/%s",

dns_protocol_to_string(t->scope->protocol),

t->scope->link ? t->scope->link->name : "*",

t->scope->family == AF_UNSPEC ? "*" : af_to_name(t->scope->family));

if (t->n_attempts >= TRANSACTION_ATTEMPTS_MAX(t->scope->protocol)) {

dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);

return 0;

}

if (t->scope->protocol == DNS_PROTOCOL_LLMNR && had_stream) {

/* If we already tried via a stream, then we don't

dns_transaction_complete(t, DNS_TRANSACTION_ATTEMPTS_MAX_REACHED);

return 0;

}

assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);

t->n_attempts++;

t->start_usec = ts;

t->received = dns_packet_unref(t->received);

t->answer = dns_answer_unref(t->answer);

t->answer_rcode = 0;

/* Check the zone, but obly if this transaction is not used

if (set_isempty(t->zone_items)) {

r = dns_zone_lookup(&t->scope->zone, t->key, &t->answer, NULL, NULL);

if (r < 0)

return r;

if (r > 0) {

t->answer_rcode = DNS_RCODE_SUCCESS;

dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);

return 0;

}

}

/* Check the cache, but only if this transaction is not used

if (set_isempty(t->zone_items)) {

/* Before trying the cache, let's make sure we figured out a

dns_scope_get_dns_server(t->scope);

/* Let's then prune all outdated entries */

dns_cache_prune(&t->scope->cache);

r = dns_cache_lookup(&t->scope->cache, t->key, &t->answer_rcode, &t->answer);

if (r < 0)

return r;

if (r > 0) {

if (t->answer_rcode == DNS_RCODE_SUCCESS)

dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);

else

dns_transaction_complete(t, DNS_TRANSACTION_FAILURE);

return 0;

}

}

if (t->scope->protocol == DNS_PROTOCOL_LLMNR && !t->initial_jitter) {

usec_t jitter;

/* RFC 4795 Section 2.7 suggests all queries should be

t->initial_jitter = true;

random_bytes(&jitter, sizeof(jitter));

jitter %= LLMNR_JITTER_INTERVAL_USEC;

r = sd_event_add_time(

t->scope->manager->event,

&t->timeout_event_source,

clock_boottime_or_monotonic(),

ts + jitter,

LLMNR_JITTER_INTERVAL_USEC,

on_transaction_timeout, t);

if (r < 0)

return r;

t->n_attempts = 0;

t->state = DNS_TRANSACTION_PENDING;

log_debug("Delaying LLMNR transaction for " USEC_FMT "us.", jitter);

return 0;

}

/* Otherwise, we need to ask the network */

r = dns_transaction_make_packet(t);

if (r == -EDOM) {

/* Not the right request to make on this network?

dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);

return 0;

}

if (r < 0)

return r;

if (t->scope->protocol == DNS_PROTOCOL_LLMNR &&

(dns_name_endswith(DNS_RESOURCE_KEY_NAME(t->key), "in-addr.arpa") > 0 ||

dns_name_endswith(DNS_RESOURCE_KEY_NAME(t->key), "ip6.arpa") > 0)) {

/* RFC 4795, Section 2.4. says reverse lookups shall

r = dns_transaction_open_tcp(t);

} else {

/* Try via UDP, and if that fails due to large size try via TCP */

r = dns_transaction_emit(t);

if (r == -EMSGSIZE)

r = dns_transaction_open_tcp(t);

}

if (r == -ESRCH) {

/* No servers to send this to? */

dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS);

return 0;

} else if (r < 0) {

if (t->scope->protocol != DNS_PROTOCOL_DNS) {

dns_transaction_complete(t, DNS_TRANSACTION_RESOURCES);

return 0;

}

/* Couldn't send? Try immediately again, with a new server */

dns_transaction_next_dns_server(t);

return dns_transaction_go(t);

}

r = sd_event_add_time(

t->scope->manager->event,

&t->timeout_event_source,

clock_boottime_or_monotonic(),

ts + transaction_get_resend_timeout(t), 0,

on_transaction_timeout, t);

if (r < 0)

return r;

t->state = DNS_TRANSACTION_PENDING;

return 1;

}

static const char* const dns_transaction_state_table[_DNS_TRANSACTION_STATE_MAX] = {

[DNS_TRANSACTION_NULL] = "null",

[DNS_TRANSACTION_PENDING] = "pending",

[DNS_TRANSACTION_FAILURE] = "failure",

[DNS_TRANSACTION_SUCCESS] = "success",

[DNS_TRANSACTION_NO_SERVERS] = "no-servers",

[DNS_TRANSACTION_TIMEOUT] = "timeout",

[DNS_TRANSACTION_ATTEMPTS_MAX_REACHED] = "attempts-max-reached",

[DNS_TRANSACTION_INVALID_REPLY] = "invalid-reply",

[DNS_TRANSACTION_RESOURCES] = "resources",

[DNS_TRANSACTION_ABORTED] = "aborted",

};

DEFINE_STRING_TABLE_LOOKUP(dns_transaction_state, DnsTransactionState);