/* SPDX-License-Identifier: LGPL-2.1+ */
-/***
- This file is part of systemd.
-
- Copyright 2014 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
#include <netinet/tcp.h>
#define DNS_STREAM_TIMEOUT_USEC (10 * USEC_PER_SEC)
#define DNS_STREAMS_MAX 128
+#define DNS_QUERIES_PER_STREAM 32
+
static void dns_stream_stop(DnsStream *s) {
assert(s);
s->io_event_source = sd_event_source_unref(s->io_event_source);
s->timeout_event_source = sd_event_source_unref(s->timeout_event_source);
s->fd = safe_close(s->fd);
+
+ /* Disconnect us from the server object if we are now not usable anymore */
+ dns_stream_detach(s);
}
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;
- if (!s->read_packet || s->n_read < sizeof(s->read_size) + s->read_packet->size)
+ 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;
+ }
+
+ /* Let's read a packet if we haven't queued any yet. Except if we already hit a limit of parallel
+ * queries for this connection. */
+ if ((!s->read_packet || s->n_read < sizeof(s->read_size) + s->read_packet->size) &&
+ set_size(s->queries) < DNS_QUERIES_PER_STREAM)
f |= EPOLLIN;
+#if ENABLE_DNS_OVER_TLS
+ /* For handshake and clean closing purposes, TLS can override requested events */
+ if (s->dnstls_events != 0)
+ f = s->dnstls_events;
+#endif
+
return sd_event_source_set_io_events(s->io_event_source, f);
}
static int dns_stream_complete(DnsStream *s, int error) {
+ _cleanup_(dns_stream_unrefp) _unused_ DnsStream *ref = dns_stream_ref(s); /* Protect stream while we process it */
+
assert(s);
+ assert(error >= 0);
- dns_stream_stop(s);
+ /* Error is > 0 when the connection failed for some reason in the network stack. It's == 0 if we sent
+ * and received exactly one packet each (in the LLMNR client case). */
+
+#if ENABLE_DNS_OVER_TLS
+ if (s->encrypted) {
+ int r;
+
+ r = dnstls_stream_shutdown(s, error);
+ if (r != -EAGAIN)
+ dns_stream_stop(s);
+ } else
+#endif
+ dns_stream_stop(s);
+
+ dns_stream_detach(s);
if (s->complete)
s->complete(s, error);
return 0;
}
+ssize_t dns_stream_writev(DnsStream *s, const struct iovec *iov, size_t iovcnt, int flags) {
+ ssize_t m;
+
+ assert(s);
+ assert(iov);
+
+#if ENABLE_DNS_OVER_TLS
+ if (s->encrypted && !(flags & DNS_STREAM_WRITE_TLS_DATA)) {
+ ssize_t ss;
+ size_t i;
+
+ m = 0;
+ for (i = 0; i < iovcnt; i++) {
+ ss = dnstls_stream_write(s, iov[i].iov_base, iov[i].iov_len);
+ if (ss < 0)
+ return ss;
+
+ m += ss;
+ if (ss != (ssize_t) iov[i].iov_len)
+ continue;
+ }
+ } else
+#endif
+ if (s->tfo_salen > 0) {
+ struct msghdr hdr = {
+ .msg_iov = (struct iovec*) iov,
+ .msg_iovlen = iovcnt,
+ .msg_name = &s->tfo_address.sa,
+ .msg_namelen = s->tfo_salen
+ };
+
+ m = sendmsg(s->fd, &hdr, MSG_FASTOPEN);
+ if (m < 0) {
+ if (errno == EOPNOTSUPP) {
+ s->tfo_salen = 0;
+ if (connect(s->fd, &s->tfo_address.sa, s->tfo_salen) < 0)
+ return -errno;
+
+ return -EAGAIN;
+ }
+ if (errno == EINPROGRESS)
+ return -EAGAIN;
+
+ return -errno;
+ } else
+ s->tfo_salen = 0; /* connection is made */
+ } else {
+ m = writev(s->fd, iov, iovcnt);
+ if (m < 0)
+ return -errno;
+ }
+
+ return m;
+}
+
+static ssize_t dns_stream_read(DnsStream *s, void *buf, size_t count) {
+ ssize_t ss;
+
+#if ENABLE_DNS_OVER_TLS
+ if (s->encrypted)
+ ss = dnstls_stream_read(s, buf, count);
+ else
+#endif
+ {
+ ss = read(s->fd, buf, count);
+ if (ss < 0)
+ return -errno;
+ }
+
+ return ss;
+}
+
static int on_stream_timeout(sd_event_source *es, usec_t usec, void *userdata) {
DnsStream *s = userdata;
}
static int on_stream_io(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
- DnsStream *s = userdata;
+ _cleanup_(dns_stream_unrefp) DnsStream *s = dns_stream_ref(userdata); /* Protect stream while we process it */
+ bool progressed = false;
int r;
assert(s);
- r = dns_stream_identify(s);
- if (r < 0)
- return dns_stream_complete(s, -r);
+#if ENABLE_DNS_OVER_TLS
+ if (s->encrypted) {
+ r = dnstls_stream_on_io(s, revents);
+ if (r == DNSTLS_STREAM_CLOSED)
+ return 0;
+ if (r == -EAGAIN)
+ return dns_stream_update_io(s);
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+
+ r = dns_stream_update_io(s);
+ if (r < 0)
+ return r;
+ }
+#endif
+
+ /* only identify after connecting */
+ if (s->tfo_salen == 0) {
+ r = dns_stream_identify(s);
+ if (r < 0)
+ return dns_stream_complete(s, -r);
+ }
if ((revents & EPOLLOUT) &&
s->write_packet &&
struct iovec iov[2];
ssize_t ss;
- iov[0].iov_base = &s->write_size;
- iov[0].iov_len = sizeof(s->write_size);
- iov[1].iov_base = DNS_PACKET_DATA(s->write_packet);
- iov[1].iov_len = s->write_packet->size;
+ iov[0] = IOVEC_MAKE(&s->write_size, sizeof(s->write_size));
+ iov[1] = IOVEC_MAKE(DNS_PACKET_DATA(s->write_packet), s->write_packet->size);
IOVEC_INCREMENT(iov, 2, s->n_written);
- ss = writev(fd, iov, 2);
+ ss = dns_stream_writev(s, iov, 2, 0);
if (ss < 0) {
- if (!IN_SET(errno, EINTR, EAGAIN))
- return dns_stream_complete(s, errno);
- } else
+ if (!IN_SET(-ss, EINTR, EAGAIN))
+ return dns_stream_complete(s, -ss);
+ } else {
+ progressed = true;
s->n_written += ss;
+ }
/* Are we done? If so, disable the event source for EPOLLOUT */
if (s->n_written >= sizeof(s->write_size) + s->write_packet->size) {
if (s->n_read < sizeof(s->read_size)) {
ssize_t ss;
- ss = read(fd, (uint8_t*) &s->read_size + s->n_read, sizeof(s->read_size) - s->n_read);
+ ss = dns_stream_read(s, (uint8_t*) &s->read_size + s->n_read, sizeof(s->read_size) - s->n_read);
if (ss < 0) {
- if (!IN_SET(errno, EINTR, EAGAIN))
- return dns_stream_complete(s, errno);
+ if (!IN_SET(-ss, EINTR, EAGAIN))
+ return dns_stream_complete(s, -ss);
} else if (ss == 0)
return dns_stream_complete(s, ECONNRESET);
- else
+ else {
+ progressed = true;
s->n_read += ss;
+ }
}
if (s->n_read >= sizeof(s->read_size)) {
}
}
- ss = read(fd,
+ ss = dns_stream_read(s,
(uint8_t*) DNS_PACKET_DATA(s->read_packet) + s->n_read - sizeof(s->read_size),
sizeof(s->read_size) + be16toh(s->read_size) - s->n_read);
if (ss < 0) {
- if (!IN_SET(errno, EINTR, EAGAIN))
- return dns_stream_complete(s, errno);
+ if (!IN_SET(-ss, EINTR, EAGAIN))
+ return dns_stream_complete(s, -ss);
} else if (ss == 0)
return dns_stream_complete(s, ECONNRESET);
else
/* 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);
}
}
}
- if ((s->write_packet && s->n_written >= sizeof(s->write_size) + s->write_packet->size) &&
+ /* Call "complete" callback if finished reading and writing one packet, and there's nothing else left
+ * to write. */
+ if (s->type == DNS_STREAM_LLMNR_SEND &&
+ (s->write_packet && s->n_written >= sizeof(s->write_size) + s->write_packet->size) &&
+ ordered_set_isempty(s->write_queue) &&
(s->read_packet && s->n_read >= sizeof(s->read_size) + s->read_packet->size))
return dns_stream_complete(s, 0);
+ /* If we did something, let's restart the timeout event source */
+ if (progressed && s->timeout_event_source) {
+ r = sd_event_source_set_time(s->timeout_event_source, now(clock_boottime_or_monotonic()) + DNS_STREAM_TIMEOUT_USEC);
+ if (r < 0)
+ log_warning_errno(errno, "Couldn't restart TCP connection timeout, ignoring: %m");
+ }
+
return 0;
}
-DnsStream *dns_stream_unref(DnsStream *s) {
- if (!s)
- return NULL;
-
- assert(s->n_ref > 0);
- s->n_ref--;
+static DnsStream *dns_stream_free(DnsStream *s) {
+ DnsPacket *p;
+ Iterator i;
- if (s->n_ref > 0)
- return NULL;
+ assert(s);
dns_stream_stop(s);
if (s->manager) {
LIST_REMOVE(streams, s->manager->dns_streams, s);
- s->manager->n_dns_streams--;
+ s->manager->n_dns_streams[s->type]--;
}
+#if ENABLE_DNS_OVER_TLS
+ if (s->encrypted)
+ dnstls_stream_free(s);
+#endif
+
+ 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);
+DEFINE_TRIVIAL_REF_UNREF_FUNC(DnsStream, dns_stream, dns_stream_free);
-DnsStream *dns_stream_ref(DnsStream *s) {
- if (!s)
- return NULL;
-
- assert(s->n_ref > 0);
- s->n_ref++;
-
- return s;
-}
+int dns_stream_new(
+ Manager *m,
+ DnsStream **ret,
+ DnsStreamType type,
+ DnsProtocol protocol,
+ int fd,
+ const union sockaddr_union *tfo_address) {
-int dns_stream_new(Manager *m, DnsStream **ret, DnsProtocol protocol, int fd) {
_cleanup_(dns_stream_unrefp) DnsStream *s = NULL;
int r;
assert(m);
+ assert(ret);
+ assert(type >= 0);
+ assert(type < _DNS_STREAM_TYPE_MAX);
+ assert(protocol >= 0);
+ assert(protocol < _DNS_PROTOCOL_MAX);
assert(fd >= 0);
- if (m->n_dns_streams > DNS_STREAMS_MAX)
+ if (m->n_dns_streams[type] > DNS_STREAMS_MAX)
return -EBUSY;
- s = new0(DnsStream, 1);
+ s = new(DnsStream, 1);
if (!s)
return -ENOMEM;
- s->n_ref = 1;
- s->fd = -1;
- s->protocol = protocol;
+ *s = (DnsStream) {
+ .n_ref = 1,
+ .fd = -1,
+ .protocol = protocol,
+ };
+
+ r = ordered_set_ensure_allocated(&s->write_queue, &dns_packet_hash_ops);
+ if (r < 0)
+ return r;
r = sd_event_add_io(m->event, &s->io_event_source, fd, EPOLLIN, on_stream_io, s);
if (r < 0)
(void) sd_event_source_set_description(s->timeout_event_source, "dns-stream-timeout");
LIST_PREPEND(streams, m->dns_streams, s);
+ m->n_dns_streams[type]++;
s->manager = m;
+
s->fd = fd;
- m->n_dns_streams++;
- *ret = s;
- s = NULL;
+ if (tfo_address) {
+ s->tfo_address = *tfo_address;
+ s->tfo_salen = tfo_address->sa.sa_family == AF_INET6 ? sizeof(tfo_address->in6) : sizeof(tfo_address->in);
+ }
+
+ *ret = TAKE_PTR(s);
return 0;
}
int dns_stream_write_packet(DnsStream *s, DnsPacket *p) {
+ int r;
+
assert(s);
+ assert(p);
- 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);
}
+
+DnsPacket *dns_stream_take_read_packet(DnsStream *s) {
+ assert(s);
+
+ if (!s->read_packet)
+ return NULL;
+
+ if (s->n_read < sizeof(s->read_size))
+ return NULL;
+
+ if (s->n_read < sizeof(s->read_size) + be16toh(s->read_size))
+ return NULL;
+
+ s->n_read = 0;
+ return TAKE_PTR(s->read_packet);
+}
+
+void dns_stream_detach(DnsStream *s) {
+ assert(s);
+
+ if (!s->server)
+ return;
+
+ if (s->server->stream != s)
+ return;
+
+ dns_server_unref_stream(s->server);
+}
projects / thirdparty / systemd.git / blobdiff