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Diffstat (limited to 'src/resolve/resolved-dns-transaction.c')
-rw-r--r--src/resolve/resolved-dns-transaction.c335
1 files changed, 174 insertions, 161 deletions
diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c
index e468f245f7..b30473dd7e 100644
--- a/src/resolve/resolved-dns-transaction.c
+++ b/src/resolve/resolved-dns-transaction.c
@@ -24,6 +24,7 @@
#include "resolved-llmnr.h"
#include "resolved-dns-transaction.h"
#include "random-util.h"
+#include "dns-domain.h"
DnsTransaction* dns_transaction_free(DnsTransaction *t) {
DnsQuery *q;
@@ -34,26 +35,25 @@ DnsTransaction* dns_transaction_free(DnsTransaction *t) {
sd_event_source_unref(t->timeout_event_source);
- dns_question_unref(t->question);
dns_packet_unref(t->sent);
dns_packet_unref(t->received);
dns_answer_unref(t->cached);
- sd_event_source_unref(t->dns_ipv4_event_source);
- sd_event_source_unref(t->dns_ipv6_event_source);
- safe_close(t->dns_ipv4_fd);
- safe_close(t->dns_ipv6_fd);
+ sd_event_source_unref(t->dns_udp_event_source);
+ safe_close(t->dns_udp_fd);
dns_server_unref(t->server);
dns_stream_free(t->stream);
if (t->scope) {
- LIST_REMOVE(transactions_by_scope, t->scope->transactions, t);
+ hashmap_remove(t->scope->transactions, t->key);
if (t->id != 0)
hashmap_remove(t->scope->manager->dns_transactions, UINT_TO_PTR(t->id));
}
+ dns_resource_key_unref(t->key);
+
while ((q = set_steal_first(t->queries)))
set_remove(q->transactions, t);
set_free(t->queries);
@@ -78,26 +78,30 @@ void dns_transaction_gc(DnsTransaction *t) {
dns_transaction_free(t);
}
-int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsQuestion *q) {
+int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key) {
_cleanup_(dns_transaction_freep) DnsTransaction *t = NULL;
int r;
assert(ret);
assert(s);
- assert(q);
+ assert(key);
r = hashmap_ensure_allocated(&s->manager->dns_transactions, NULL);
if (r < 0)
return r;
+ r = hashmap_ensure_allocated(&s->transactions, &dns_resource_key_hash_ops);
+ if (r < 0)
+ return r;
+
t = new0(DnsTransaction, 1);
if (!t)
return -ENOMEM;
- t->dns_ipv4_fd = t->dns_ipv6_fd = -1;
-
- t->question = dns_question_ref(q);
+ t->dns_udp_fd = -1;
+ t->key = dns_resource_key_ref(key);
+ /* Find a fresh, unused transaction id */
do
random_bytes(&t->id, sizeof(t->id));
while (t->id == 0 ||
@@ -109,7 +113,12 @@ int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsQuestion *q) {
return r;
}
- LIST_PREPEND(transactions_by_scope, s->transactions, t);
+ r = hashmap_put(s->transactions, t->key, t);
+ if (r < 0) {
+ hashmap_remove(s->manager->dns_transactions, UINT_TO_PTR(t->id));
+ return r;
+ }
+
t->scope = s;
if (ret)
@@ -177,9 +186,6 @@ void dns_transaction_complete(DnsTransaction *t, DnsTransactionState state) {
assert(t);
assert(!IN_SET(state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING));
- if (!IN_SET(t->state, DNS_TRANSACTION_NULL, DNS_TRANSACTION_PENDING))
- return;
-
/* Note that this call might invalidate the query. Callers
* should hence not attempt to access the query or transaction
* after calling this function. */
@@ -245,7 +251,7 @@ static int on_stream_complete(DnsStream *s, int error) {
}
static int dns_transaction_open_tcp(DnsTransaction *t) {
- _cleanup_(dns_server_unrefp) DnsServer *server = NULL;
+ DnsServer *server = NULL;
_cleanup_close_ int fd = -1;
int r;
@@ -254,11 +260,13 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
if (t->stream)
return 0;
- if (t->scope->protocol == DNS_PROTOCOL_DNS)
+ switch (t->scope->protocol) {
+ case DNS_PROTOCOL_DNS:
fd = dns_scope_tcp_socket(t->scope, AF_UNSPEC, NULL, 53, &server);
- else if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
+ break;
- /* When we already received a query to this (but it was truncated), send to its sender address */
+ case DNS_PROTOCOL_LLMNR:
+ /* When we already received a reply to this (but it was truncated), send to its sender address */
if (t->received)
fd = dns_scope_tcp_socket(t->scope, t->received->family, &t->received->sender, t->received->sender_port, NULL);
else {
@@ -268,16 +276,23 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
/* Otherwise, try to talk to the owner of a
* the IP address, in case this is a reverse
* PTR lookup */
- r = dns_question_extract_reverse_address(t->question, &family, &address);
+
+ r = dns_name_address(DNS_RESOURCE_KEY_NAME(t->key), &family, &address);
if (r < 0)
return r;
if (r == 0)
return -EINVAL;
+ if (family != t->scope->family)
+ return -ESRCH;
fd = dns_scope_tcp_socket(t->scope, family, &address, LLMNR_PORT, NULL);
}
- } else
+
+ break;
+
+ default:
return -EAFNOSUPPORT;
+ }
if (fd < 0)
return fd;
@@ -294,7 +309,6 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
return r;
}
-
dns_server_unref(t->server);
t->server = dns_server_ref(server);
t->received = dns_packet_unref(t->received);
@@ -310,18 +324,32 @@ static int dns_transaction_open_tcp(DnsTransaction *t) {
return 0;
}
+static void dns_transaction_next_dns_server(DnsTransaction *t) {
+ assert(t);
+
+ t->server = dns_server_unref(t->server);
+ t->dns_udp_event_source = sd_event_source_unref(t->dns_udp_event_source);
+ t->dns_udp_fd = safe_close(t->dns_udp_fd);
+
+ dns_scope_next_dns_server(t->scope);
+}
+
void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
+ usec_t ts;
int r;
assert(t);
assert(p);
assert(t->state == DNS_TRANSACTION_PENDING);
+ assert(t->scope);
+ assert(t->scope->manager);
/* Note that this call might invalidate the query. Callers
* should hence not attempt to access the query or transaction
* after calling this function. */
- if (t->scope->protocol == DNS_PROTOCOL_LLMNR) {
+ switch (t->scope->protocol) {
+ case DNS_PROTOCOL_LLMNR:
assert(t->scope->link);
/* For LLMNR we will not accept any packets from other
@@ -340,24 +368,14 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
dns_transaction_tentative(t, p);
return;
}
- }
-
- if (t->scope->protocol == DNS_PROTOCOL_DNS) {
-
- /* For DNS we are fine with accepting packets on any
- * interface, but the source IP address must be the
- * one of the DNS server we queried */
-
- assert(t->server);
- if (t->server->family != p->family)
- return;
+ break;
- if (!in_addr_equal(p->family, &p->sender, &t->server->address))
- return;
+ case DNS_PROTOCOL_DNS:
+ break;
- if (p->sender_port != 53)
- return;
+ default:
+ assert_not_reached("Invalid DNS protocol.");
}
if (t->received != p) {
@@ -379,6 +397,24 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
}
}
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
+ switch (t->scope->protocol) {
+ case DNS_PROTOCOL_DNS:
+ assert(t->server);
+
+ dns_server_packet_received(t->server, ts - t->start_usec);
+
+ break;
+ case DNS_PROTOCOL_LLMNR:
+ case DNS_PROTOCOL_MDNS:
+ dns_scope_packet_received(t->scope, ts - t->start_usec);
+
+ break;
+ default:
+ break;
+ }
+
if (DNS_PACKET_TC(p)) {
/* Response was truncated, let's try again with good old TCP */
r = dns_transaction_open_tcp(t);
@@ -396,7 +432,7 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
}
/* On DNS, couldn't send? Try immediately again, with a new server */
- dns_scope_next_dns_server(t->scope);
+ dns_transaction_next_dns_server(t);
r = dns_transaction_go(t);
if (r < 0) {
@@ -416,12 +452,13 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
}
/* Only consider responses with equivalent query section to the request */
- if (!dns_question_is_superset(p->question, t->question) ||
- !dns_question_is_superset(t->question, p->question))
+ if (p->question->n_keys != 1 || dns_resource_key_equal(p->question->keys[0], t->key) <= 0) {
dns_transaction_complete(t, DNS_TRANSACTION_INVALID_REPLY);
+ return;
+ }
/* According to RFC 4795, section 2.9. only the RRs from the answer section shall be cached */
- dns_cache_put(&t->scope->cache, p->question, DNS_PACKET_RCODE(p), p->answer, DNS_PACKET_ANCOUNT(p), 0, p->family, &p->sender);
+ dns_cache_put(&t->scope->cache, t->key, DNS_PACKET_RCODE(p), p->answer, DNS_PACKET_ANCOUNT(p), 0, p->family, &p->sender);
if (DNS_PACKET_RCODE(p) == DNS_RCODE_SUCCESS)
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
@@ -429,6 +466,56 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) {
dns_transaction_complete(t, DNS_TRANSACTION_FAILURE);
}
+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;
@@ -437,7 +524,13 @@ static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdat
assert(t);
/* Timeout reached? Try again, with a new server */
- dns_scope_next_dns_server(t->scope);
+ 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)
@@ -448,7 +541,6 @@ static int on_transaction_timeout(sd_event_source *s, usec_t usec, void *userdat
static int dns_transaction_make_packet(DnsTransaction *t) {
_cleanup_(dns_packet_unrefp) DnsPacket *p = NULL;
- unsigned n, added = 0;
int r;
assert(t);
@@ -460,24 +552,17 @@ static int dns_transaction_make_packet(DnsTransaction *t) {
if (r < 0)
return r;
- for (n = 0; n < t->question->n_keys; n++) {
- r = dns_scope_good_key(t->scope, t->question->keys[n]);
- if (r < 0)
- return r;
- if (r == 0)
- continue;
-
- r = dns_packet_append_key(p, t->question->keys[n], NULL);
- if (r < 0)
- return r;
-
- added++;
- }
-
- if (added <= 0)
+ r = dns_scope_good_key(t->scope, t->key);
+ if (r < 0)
+ return r;
+ if (r == 0)
return -EDOM;
- DNS_PACKET_HEADER(p)->qdcount = htobe16(added);
+ 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;
@@ -486,8 +571,26 @@ static int dns_transaction_make_packet(DnsTransaction *t) {
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);
@@ -513,8 +616,10 @@ int dns_transaction_go(DnsTransaction *t) {
return 0;
}
+ assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &ts) >= 0);
+
t->n_attempts++;
- t->server = dns_server_unref(t->server);
+ t->start_usec = ts;
t->received = dns_packet_unref(t->received);
t->cached = dns_answer_unref(t->cached);
t->cached_rcode = 0;
@@ -531,11 +636,10 @@ int dns_transaction_go(DnsTransaction *t) {
/* Let's then prune all outdated entries */
dns_cache_prune(&t->scope->cache);
- r = dns_cache_lookup(&t->scope->cache, t->question, &t->cached_rcode, &t->cached);
+ r = dns_cache_lookup(&t->scope->cache, t->key, &t->cached_rcode, &t->cached);
if (r < 0)
return r;
if (r > 0) {
- log_debug("Cache hit!");
if (t->cached_rcode == DNS_RCODE_SUCCESS)
dns_transaction_complete(t, DNS_TRANSACTION_SUCCESS);
else
@@ -559,7 +663,7 @@ int dns_transaction_go(DnsTransaction *t) {
t->scope->manager->event,
&t->timeout_event_source,
clock_boottime_or_monotonic(),
- now(clock_boottime_or_monotonic()) + jitter,
+ ts + jitter,
LLMNR_JITTER_INTERVAL_USEC,
on_transaction_timeout, t);
if (r < 0)
@@ -572,8 +676,6 @@ int dns_transaction_go(DnsTransaction *t) {
return 0;
}
- log_debug("Cache miss!");
-
/* Otherwise, we need to ask the network */
r = dns_transaction_make_packet(t);
if (r == -EDOM) {
@@ -587,20 +689,16 @@ int dns_transaction_go(DnsTransaction *t) {
return r;
if (t->scope->protocol == DNS_PROTOCOL_LLMNR &&
- (dns_question_endswith(t->question, "in-addr.arpa") > 0 ||
- dns_question_endswith(t->question, "ip6.arpa") > 0)) {
+ (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
* always be made via TCP on LLMNR */
r = dns_transaction_open_tcp(t);
} else {
- DnsServer *server;
-
/* Try via UDP, and if that fails due to large size try via TCP */
- r = dns_scope_emit(t->scope, t, t->sent, &server);
- if (r >= 0)
- t->server = dns_server_ref(server);
- else if (r == -EMSGSIZE)
+ r = dns_transaction_emit(t);
+ if (r == -EMSGSIZE)
r = dns_transaction_open_tcp(t);
}
if (r == -ESRCH) {
@@ -614,7 +712,7 @@ int dns_transaction_go(DnsTransaction *t) {
}
/* Couldn't send? Try immediately again, with a new server */
- dns_scope_next_dns_server(t->scope);
+ dns_transaction_next_dns_server(t);
return dns_transaction_go(t);
}
@@ -623,7 +721,7 @@ int dns_transaction_go(DnsTransaction *t) {
t->scope->manager->event,
&t->timeout_event_source,
clock_boottime_or_monotonic(),
- now(clock_boottime_or_monotonic()) + TRANSACTION_TIMEOUT_USEC(t->scope->protocol), 0,
+ ts + transaction_get_resend_timeout(t), 0,
on_transaction_timeout, t);
if (r < 0)
return r;
@@ -632,91 +730,6 @@ int dns_transaction_go(DnsTransaction *t) {
return 1;
}
-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;
-}
-
-int transaction_dns_ipv4_fd(DnsTransaction *t) {
- const int one = 1;
- int r;
-
- assert(t);
- assert(t->scope);
- assert(t->scope->manager);
-
- if (t->dns_ipv4_fd >= 0)
- return t->dns_ipv4_fd;
-
- t->dns_ipv4_fd = socket(AF_INET, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
- if (t->dns_ipv4_fd < 0)
- return -errno;
-
- r = setsockopt(t->dns_ipv4_fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
-
- r = sd_event_add_io(t->scope->manager->event, &t->dns_ipv4_event_source, t->dns_ipv4_fd, EPOLLIN, on_dns_packet, t);
- if (r < 0)
- goto fail;
-
- return t->dns_ipv4_fd;
-
-fail:
- t->dns_ipv4_fd = safe_close(t->dns_ipv4_fd);
- return r;
-}
-
-int transaction_dns_ipv6_fd(DnsTransaction *t) {
- const int one = 1;
- int r;
-
- assert(t);
- assert(t->scope);
- assert(t->scope->manager);
-
- if (t->dns_ipv6_fd >= 0)
- return t->dns_ipv6_fd;
-
- t->dns_ipv6_fd = socket(AF_INET6, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
- if (t->dns_ipv6_fd < 0)
- return -errno;
-
- r = setsockopt(t->dns_ipv6_fd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &one, sizeof(one));
- if (r < 0) {
- r = -errno;
- goto fail;
- }
-
- r = sd_event_add_io(t->scope->manager->event, &t->dns_ipv6_event_source, t->dns_ipv6_fd, EPOLLIN, on_dns_packet, t);
- if (r < 0)
- goto fail;
-
- return t->dns_ipv6_fd;
-
-fail:
- t->dns_ipv6_fd = safe_close(t->dns_ipv6_fd);
- return r;
-}
-
static const char* const dns_transaction_state_table[_DNS_TRANSACTION_STATE_MAX] = {
[DNS_TRANSACTION_NULL] = "null",
[DNS_TRANSACTION_PENDING] = "pending",
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2025-04-03 11:10:03 +0000