diff options
Diffstat (limited to 'src/resolve')
| -rw-r--r-- | src/resolve/resolved-dns-packet.c | 25 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-packet.h | 2 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-server.c | 2 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-server.h | 1 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-stream.c | 51 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-stream.h | 6 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-transaction.c | 149 | ||||
| -rw-r--r-- | src/resolve/resolved-dns-transaction.h | 1 |
8 files changed, 180 insertions, 57 deletions
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c index f5aeb3459c..48c799786c 100644 --- a/src/resolve/resolved-dns-packet.c +++ b/src/resolve/resolved-dns-packet.c @@ -2333,6 +2333,31 @@ int dns_packet_is_reply_for(DnsPacket *p, const DnsResourceKey *key) { return dns_resource_key_equal(p->question->keys[0], key); } +static void dns_packet_hash_func(const void *p, struct siphash *state) { + const DnsPacket *s = p; + + assert(s); + + siphash24_compress(&s->size, sizeof(s->size), state); + siphash24_compress(DNS_PACKET_DATA((DnsPacket*) s), s->size, state); +} + +static int dns_packet_compare_func(const void *a, const void *b) { + const DnsPacket *x = a, *y = b; + + if (x->size < y->size) + return -1; + if (x->size > y->size) + return 1; + + return memcmp(DNS_PACKET_DATA((DnsPacket*) x), DNS_PACKET_DATA((DnsPacket*) y), x->size); +} + +const struct hash_ops dns_packet_hash_ops = { + .hash = dns_packet_hash_func, + .compare = dns_packet_compare_func +}; + static const char* const dns_rcode_table[_DNS_RCODE_MAX_DEFINED] = { [DNS_RCODE_SUCCESS] = "SUCCESS", [DNS_RCODE_FORMERR] = "FORMERR", diff --git a/src/resolve/resolved-dns-packet.h b/src/resolve/resolved-dns-packet.h index df4b972648..3a3a3e2fd5 100644 --- a/src/resolve/resolved-dns-packet.h +++ b/src/resolve/resolved-dns-packet.h @@ -270,6 +270,8 @@ DnsProtocol dns_protocol_from_string(const char *s) _pure_; #define MDNS_MULTICAST_IPV4_ADDRESS ((struct in_addr) { .s_addr = htobe32(224U << 24 | 251U) }) #define MDNS_MULTICAST_IPV6_ADDRESS ((struct in6_addr) { .s6_addr = { 0xFF, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfb } }) +extern const struct hash_ops dns_packet_hash_ops; + static inline uint64_t SD_RESOLVED_FLAGS_MAKE(DnsProtocol protocol, int family, bool authenticated) { uint64_t f; diff --git a/src/resolve/resolved-dns-server.c b/src/resolve/resolved-dns-server.c index 35860e99db..aef853a7d2 100644 --- a/src/resolve/resolved-dns-server.c +++ b/src/resolve/resolved-dns-server.c @@ -123,6 +123,8 @@ DnsServer* dns_server_unref(DnsServer *s) { if (s->n_ref > 0) return NULL; + dns_stream_unref(s->stream); + free(s->server_string); return mfree(s); } diff --git a/src/resolve/resolved-dns-server.h b/src/resolve/resolved-dns-server.h index 36006904bf..e0e713e9ca 100644 --- a/src/resolve/resolved-dns-server.h +++ b/src/resolve/resolved-dns-server.h @@ -53,6 +53,7 @@ struct DnsServer { int ifindex; /* for IPv6 link-local DNS servers */ char *server_string; + DnsStream *stream; usec_t resend_timeout; usec_t max_rtt; diff --git a/src/resolve/resolved-dns-stream.c b/src/resolve/resolved-dns-stream.c index 85745e74ac..f537fe6ab4 100644 --- a/src/resolve/resolved-dns-stream.c +++ b/src/resolve/resolved-dns-stream.c @@ -31,6 +31,13 @@ static int dns_stream_update_io(DnsStream *s) { if (s->write_packet && s->n_written < sizeof(s->write_size) + s->write_packet->size) f |= EPOLLOUT; + else if (!ordered_set_isempty(s->write_queue)) { + dns_packet_unref(s->write_packet); + s->write_packet = ordered_set_steal_first(s->write_queue); + s->write_size = htobe16(s->write_packet->size); + s->n_written = 0; + f |= EPOLLOUT; + } if (!s->read_packet || s->n_read < sizeof(s->read_size) + s->read_packet->size) f |= EPOLLIN; @@ -291,15 +298,18 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use /* Are we done? If so, disable the event source for EPOLLIN */ if (s->n_read >= sizeof(s->read_size) + be16toh(s->read_size)) { - r = dns_stream_update_io(s); - if (r < 0) - return dns_stream_complete(s, -r); - /* If there's a packet handler * installed, call that. Note that * this is optional... */ - if (s->on_packet) - return s->on_packet(s); + if (s->on_packet) { + r = s->on_packet(s); + if (r < 0) + return r; + } + + r = dns_stream_update_io(s); + if (r < 0) + return dns_stream_complete(s, -r); } } } @@ -312,6 +322,9 @@ static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *use } DnsStream *dns_stream_unref(DnsStream *s) { + DnsPacket *p; + Iterator i; + if (!s) return NULL; @@ -323,19 +336,26 @@ DnsStream *dns_stream_unref(DnsStream *s) { dns_stream_stop(s); + if (s->server && s->server->stream == s) + s->server->stream = NULL; + if (s->manager) { LIST_REMOVE(streams, s->manager->dns_streams, s); s->manager->n_dns_streams--; } + ORDERED_SET_FOREACH(p, s->write_queue, i) + dns_packet_unref(ordered_set_remove(s->write_queue, p)); + dns_packet_unref(s->write_packet); dns_packet_unref(s->read_packet); + dns_server_unref(s->server); + + ordered_set_free(s->write_queue); return mfree(s); } -DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref); - DnsStream *dns_stream_ref(DnsStream *s) { if (!s) return NULL; @@ -360,6 +380,10 @@ int dns_stream_new(Manager *m, DnsStream **ret, DnsProtocol protocol, int fd) { if (!s) return -ENOMEM; + r = ordered_set_ensure_allocated(&s->write_queue, &dns_packet_hash_ops); + if (r < 0) + return r; + s->n_ref = 1; s->fd = -1; s->protocol = protocol; @@ -392,14 +416,15 @@ int dns_stream_new(Manager *m, DnsStream **ret, DnsProtocol protocol, int fd) { } int dns_stream_write_packet(DnsStream *s, DnsPacket *p) { + int r; + assert(s); - if (s->write_packet) - return -EBUSY; + r = ordered_set_put(s->write_queue, p); + if (r < 0) + return r; - s->write_packet = dns_packet_ref(p); - s->write_size = htobe16(p->size); - s->n_written = 0; + dns_packet_ref(p); return dns_stream_update_io(s); } diff --git a/src/resolve/resolved-dns-stream.h b/src/resolve/resolved-dns-stream.h index 148ef9af9d..f392c13b0b 100644 --- a/src/resolve/resolved-dns-stream.h +++ b/src/resolve/resolved-dns-stream.h @@ -43,11 +43,13 @@ struct DnsStream { be16_t write_size, read_size; DnsPacket *write_packet, *read_packet; size_t n_written, n_read; + OrderedSet *write_queue; int (*on_packet)(DnsStream *s); int (*complete)(DnsStream *s, int error); - DnsTransaction *transaction; /* when used by the transaction logic */ + LIST_HEAD(DnsTransaction, transactions); /* when used by the transaction logic */ + DnsServer *server; /* when used by the transaction logic */ DnsQuery *query; /* when used by the DNS stub logic */ LIST_FIELDS(DnsStream, streams); @@ -57,6 +59,8 @@ int dns_stream_new(Manager *m, DnsStream **s, DnsProtocol protocol, int fd); DnsStream *dns_stream_unref(DnsStream *s); DnsStream *dns_stream_ref(DnsStream *s); +DEFINE_TRIVIAL_CLEANUP_FUNC(DnsStream*, dns_stream_unref); + int dns_stream_write_packet(DnsStream *s, DnsPacket *p); static inline bool DNS_STREAM_QUEUED(DnsStream *s) { diff --git a/src/resolve/resolved-dns-transaction.c b/src/resolve/resolved-dns-transaction.c index acfe987cbe..5d3f6bae27 100644 --- a/src/resolve/resolved-dns-transaction.c +++ b/src/resolve/resolved-dns-transaction.c @@ -51,9 +51,11 @@ static void dns_transaction_close_connection(DnsTransaction *t) { if (t->stream) { /* Let's detach the stream from our transaction, in case something else keeps a reference to it. */ - t->stream->complete = NULL; - t->stream->on_packet = NULL; - t->stream->transaction = NULL; + LIST_REMOVE(transactions_by_stream, t->stream->transactions, t); + + /* Remove packet in case it's still in the queue */ + dns_packet_unref(ordered_set_remove(t->stream->write_queue, t->sent)); + t->stream = dns_stream_unref(t->stream); } @@ -448,42 +450,31 @@ static int dns_transaction_maybe_restart(DnsTransaction *t) { return 1; } -static int on_stream_complete(DnsStream *s, int error) { - _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; - DnsTransaction *t; - - assert(s); - assert(s->transaction); - - /* Copy the data we care about out of the stream before we - * destroy it. */ - t = s->transaction; - p = dns_packet_ref(s->read_packet); +static void on_transaction_stream_error(DnsTransaction *t, int error) { + assert(t); dns_transaction_close_connection(t); if (ERRNO_IS_DISCONNECT(error)) { - usec_t usec; - if (t->scope->protocol == DNS_PROTOCOL_LLMNR) { /* If the LLMNR/TCP connection failed, the host doesn't support LLMNR, and we cannot answer the * question on this scope. */ dns_transaction_complete(t, DNS_TRANSACTION_NOT_FOUND); - return 0; } - log_debug_errno(error, "Connection failure for DNS TCP stream: %m"); - assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &usec) >= 0); - dns_server_packet_lost(t->server, IPPROTO_TCP, t->current_feature_level, usec - t->start_usec); - dns_transaction_retry(t, true); - return 0; } if (error != 0) { t->answer_errno = error; dns_transaction_complete(t, DNS_TRANSACTION_ERRNO); - return 0; } +} + +static int dns_transaction_on_stream_packet(DnsTransaction *t, DnsPacket *p) { + assert(t); + assert(p); + + dns_transaction_close_connection(t); if (dns_packet_validate_reply(p) <= 0) { log_debug("Invalid TCP reply packet."); @@ -508,8 +499,64 @@ static int on_stream_complete(DnsStream *s, int error) { return 0; } -static int dns_transaction_open_tcp(DnsTransaction *t) { +static int on_stream_complete(DnsStream *s, int error) { + DnsTransaction *t, *n; + int r = 0; + + /* Do not let new transactions use this stream */ + if (s->server && s->server->stream == s) + s->server->stream = dns_stream_unref(s->server->stream); + + if (ERRNO_IS_DISCONNECT(error) && s->protocol != DNS_PROTOCOL_LLMNR) { + usec_t usec; + + log_debug_errno(error, "Connection failure for DNS TCP stream: %m"); + + if (s->transactions) { + t = s->transactions; + assert_se(sd_event_now(t->scope->manager->event, clock_boottime_or_monotonic(), &usec) >= 0); + dns_server_packet_lost(t->server, IPPROTO_UDP, t->current_feature_level, usec - t->start_usec); + } + } + + LIST_FOREACH_SAFE(transactions_by_stream, t, n, s->transactions) + if (error != 0) + on_transaction_stream_error(t, error); + else if (DNS_PACKET_ID(s->read_packet) == t->id) + /* As each transaction have a unique id the return code is only set once */ + r = dns_transaction_on_stream_packet(t, s->read_packet); + + return r; +} + +static int dns_stream_on_packet(DnsStream *s) { + _cleanup_(dns_packet_unrefp) DnsPacket *p = NULL; + int r = 0; + DnsTransaction *t; + + /* Take ownership of packet to be able to receive new packets */ + p = TAKE_PTR(s->read_packet); + s->n_read = 0; + + t = hashmap_get(s->manager->dns_transactions, UINT_TO_PTR(DNS_PACKET_ID(p))); + + /* Ignore incorrect transaction id as transaction can have been canceled */ + if (t) + r = dns_transaction_on_stream_packet(t, p); + else { + if (dns_packet_validate_reply(p) <= 0) { + log_debug("Invalid TCP reply packet."); + on_stream_complete(s, 0); + } + return 0; + } + + return r; +} + +static int dns_transaction_emit_tcp(DnsTransaction *t) { _cleanup_close_ int fd = -1; + _cleanup_(dns_stream_unrefp) DnsStream *s = NULL; int r; assert(t); @@ -530,7 +577,11 @@ static int dns_transaction_open_tcp(DnsTransaction *t) { if (r < 0) return r; - fd = dns_scope_socket_tcp(t->scope, AF_UNSPEC, NULL, t->server, 53); + if (t->server->stream) + s = dns_stream_ref(t->server->stream); + else + fd = dns_scope_socket_tcp(t->scope, AF_UNSPEC, NULL, t->server, 53); + break; case DNS_PROTOCOL_LLMNR: @@ -562,28 +613,40 @@ static int dns_transaction_open_tcp(DnsTransaction *t) { return -EAFNOSUPPORT; } - if (fd < 0) - return fd; + if (!s) { + if (fd < 0) + return fd; - r = dns_stream_new(t->scope->manager, &t->stream, t->scope->protocol, fd); - if (r < 0) - return r; - fd = -1; + r = dns_stream_new(t->scope->manager, &s, t->scope->protocol, fd); + if (r < 0) + return r; + + fd = -1; + + if (t->server) { + dns_stream_unref(t->server->stream); + t->server->stream = dns_stream_ref(s); + s->server = dns_server_ref(t->server); + } + + s->complete = on_stream_complete; + s->on_packet = dns_stream_on_packet; + + /* The interface index is difficult to determine if we are + * connecting to the local host, hence fill this in right away + * instead of determining it from the socket */ + s->ifindex = dns_scope_ifindex(t->scope); + } + + t->stream = TAKE_PTR(s); + LIST_PREPEND(transactions_by_stream, t->stream->transactions, t); r = dns_stream_write_packet(t->stream, t->sent); if (r < 0) { - t->stream = dns_stream_unref(t->stream); + dns_transaction_close_connection(t); return r; } - t->stream->complete = on_stream_complete; - t->stream->transaction = t; - - /* The interface index is difficult to determine if we are - * connecting to the local host, hence fill this in right away - * instead of determining it from the socket */ - t->stream->ifindex = dns_scope_ifindex(t->scope); - dns_transaction_reset_answer(t); t->tried_stream = true; @@ -971,7 +1034,7 @@ void dns_transaction_process_reply(DnsTransaction *t, DnsPacket *p) { log_debug("Reply truncated, retrying via TCP."); /* Response was truncated, let's try again with good old TCP */ - r = dns_transaction_open_tcp(t); + r = dns_transaction_emit_tcp(t); if (r == -ESRCH) { /* No servers found? Damn! */ dns_transaction_complete(t, DNS_TRANSACTION_NO_SERVERS); @@ -1627,7 +1690,7 @@ int dns_transaction_go(DnsTransaction *t) { /* RFC 4795, Section 2.4. says reverse lookups shall * always be made via TCP on LLMNR */ - r = dns_transaction_open_tcp(t); + r = dns_transaction_emit_tcp(t); } else { /* Try via UDP, and if that fails due to large size or lack of * support try via TCP */ @@ -1637,7 +1700,7 @@ int dns_transaction_go(DnsTransaction *t) { else if (r == -EAGAIN) log_debug("Sending query via TCP since server doesn't support UDP."); if (IN_SET(r, -EMSGSIZE, -EAGAIN)) - r = dns_transaction_open_tcp(t); + r = dns_transaction_emit_tcp(t); } if (r == -ESRCH) { diff --git a/src/resolve/resolved-dns-transaction.h b/src/resolve/resolved-dns-transaction.h index ae6d402306..8b44f65f9a 100644 --- a/src/resolve/resolved-dns-transaction.h +++ b/src/resolve/resolved-dns-transaction.h @@ -136,6 +136,7 @@ struct DnsTransaction { unsigned block_gc; LIST_FIELDS(DnsTransaction, transactions_by_scope); + LIST_FIELDS(DnsTransaction, transactions_by_stream); }; int dns_transaction_new(DnsTransaction **ret, DnsScope *s, DnsResourceKey *key); |