/*
net_socket.c -- Handle various kinds of sockets.
Copyright (C) 1998-2005 Ivo Timmermans,
- 2000-2013 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2014 Guus Sliepen <guus@tinc-vpn.org>
2006 Scott Lamb <slamb@slamb.org>
2009 Florian Forster <octo@verplant.org>
status = setsockopt(sd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof(ifr));
if(status) {
logger(DEBUG_ALWAYS, LOG_ERR, "Can't bind to interface %s: %s", iface,
- strerror(errno));
+ sockstrerror(sockerrno));
return false;
}
#else /* if !defined(SOL_SOCKET) || !defined(SO_BINDTODEVICE) */
return true;
}
+static bool bind_to_address(connection_t *c) {
+ int s = -1;
+
+ for(int i = 0; i < listen_sockets && listen_socket[i].bindto; i++) {
+ if(listen_socket[i].sa.sa.sa_family != c->address.sa.sa_family)
+ continue;
+ if(s >= 0)
+ return false;
+ s = i;
+ }
+
+ if(s < 0)
+ return false;
+
+ sockaddr_t sa = listen_socket[s].sa;
+ if(sa.sa.sa_family == AF_INET)
+ sa.in.sin_port = 0;
+ else if(sa.sa.sa_family == AF_INET6)
+ sa.in6.sin6_port = 0;
+
+ if(bind(c->socket, &sa.sa, SALEN(sa.sa))) {
+ logger(DEBUG_CONNECTIONS, LOG_WARNING, "Can't bind outgoing socket: %s", sockstrerror(sockerrno));
+ return false;
+ }
+
+ return true;
+}
+
int setup_listen_socket(const sockaddr_t *sa) {
int nfd;
char *addrstr;
if(setsockopt(nfd, SOL_SOCKET, SO_BINDTODEVICE, (void *)&ifr, sizeof ifr)) {
closesocket(nfd);
logger(DEBUG_ALWAYS, LOG_ERR, "Can't bind to interface %s: %s", iface,
- strerror(sockerrno));
+ sockstrerror(sockerrno));
return -1;
}
#else
setsockopt(nfd, SOL_SOCKET, SO_BROADCAST, (void *)&option, sizeof option);
if(udp_rcvbuf && setsockopt(nfd, SOL_SOCKET, SO_RCVBUF, (void *)&udp_rcvbuf, sizeof(udp_rcvbuf)))
- logger(DEBUG_ALWAYS, LOG_WARNING, "Can't set UDP SO_RCVBUF to %i: %s", udp_rcvbuf, strerror(errno));
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Can't set UDP SO_RCVBUF to %i: %s", udp_rcvbuf, sockstrerror(sockerrno));
if(udp_sndbuf && setsockopt(nfd, SOL_SOCKET, SO_SNDBUF, (void *)&udp_sndbuf, sizeof(udp_sndbuf)))
- logger(DEBUG_ALWAYS, LOG_WARNING, "Can't set UDP SO_SNDBUF to %i: %s", udp_sndbuf, strerror(errno));
+ logger(DEBUG_ALWAYS, LOG_WARNING, "Can't set UDP SO_SNDBUF to %i: %s", udp_sndbuf, sockstrerror(sockerrno));
#if defined(IPPROTO_IPV6) && defined(IPV6_V6ONLY)
if(sa->sa.sa_family == AF_INET6)
option = 1;
setsockopt(nfd, IPPROTO_IP, IP_DONTFRAGMENT, (void *)&option, sizeof(option));
}
-#else
-#warning No way to disable IPv4 fragmentation
#endif
#if defined(SOL_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
option = 1;
setsockopt(nfd, IPPROTO_IPV6, IPV6_DONTFRAG, (void *)&option, sizeof(option));
}
-#else
-#warning No way to disable IPv6 fragmentation
#endif
if (!bind_to_interface(nfd)) {
int fd[2];
if(socketpair(AF_UNIX, SOCK_STREAM, 0, fd)) {
- logger(DEBUG_ALWAYS, LOG_ERR, "Could not create socketpair: %s", strerror(errno));
+ logger(DEBUG_ALWAYS, LOG_ERR, "Could not create socketpair: %s", sockstrerror(sockerrno));
return;
}
ssize_t outlen = send(c->socket, c->outbuf.data + c->outbuf.offset, c->outbuf.len - c->outbuf.offset, 0);
if(outlen <= 0) {
- if(!errno || errno == EPIPE) {
+ if(!sockerrno || sockerrno == EPIPE) {
logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection closed by %s (%s)", c->name, c->hostname);
} else if(sockwouldblock(sockerrno)) {
logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Sending %d bytes to %s (%s) would block", c->outbuf.len - c->outbuf.offset, c->name, c->hostname);
return;
} else {
- logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not send %d bytes of data to %s (%s): %s", c->outbuf.len - c->outbuf.offset, c->name, c->hostname, strerror(errno));
+ logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not send %d bytes of data to %s (%s): %s", c->outbuf.len - c->outbuf.offset, c->name, c->hostname, sockstrerror(sockerrno));
}
- terminate_connection(c, c->status.active);
+ terminate_connection(c, c->edge);
return;
}
connection_t *c = data;
if(c->status.connecting) {
- c->status.connecting = false;
-
- int result;
- socklen_t len = sizeof result;
- getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len);
-
- if(!result)
- finish_connecting(c);
- else {
- logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Error while connecting to %s (%s): %s", c->name, c->hostname, sockstrerror(result));
- terminate_connection(c, false);
+ /*
+ The event loop does not protect against spurious events. Verify that we are actually connected
+ by issuing an empty send() call.
+
+ Note that the behavior of send() on potentially unconnected sockets differ between platforms:
+ +------------+-----------+-------------+-----------+
+ | Event | POSIX | Linux | Windows |
+ +------------+-----------+-------------+-----------+
+ | Spurious | ENOTCONN | EWOULDBLOCK | ENOTCONN |
+ | Failed | ENOTCONN | (cause) | ENOTCONN |
+ | Successful | (success) | (success) | (success) |
+ +------------+-----------+-------------+-----------+
+ */
+ if (send(c->socket, NULL, 0, 0) != 0) {
+ if (sockwouldblock(sockerrno))
+ return;
+ int socket_error;
+ if (!socknotconn(sockerrno))
+ socket_error = sockerrno;
+ else {
+ socklen_t len = sizeof socket_error;
+ getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&socket_error, &len);
+ }
+ if (socket_error) {
+ logger(DEBUG_CONNECTIONS, LOG_DEBUG, "Error while connecting to %s (%s): %s", c->name, c->hostname, sockstrerror(socket_error));
+ terminate_connection(c, false);
+ }
return;
}
+
+ c->status.connecting = false;
+ finish_connecting(c);
}
if(flags & IO_WRITE)
#endif
bind_to_interface(c->socket);
+ bind_to_address(c);
}
/* Connect */
c->status.connecting = true;
c->name = xstrdup(outgoing->name);
+#ifndef DISABLE_LEGACY
c->outcipher = myself->connection->outcipher;
c->outdigest = myself->connection->outdigest;
+#endif
c->outmaclength = myself->connection->outmaclength;
c->outcompression = myself->connection->outcompression;
c->last_ping_time = now.tv_sec;
return true;
}
+// Find edges pointing to this node, and use them to build a list of unique, known addresses.
+static struct addrinfo *get_known_addresses(node_t *n) {
+ struct addrinfo *ai = NULL;
+
+ for splay_each(edge_t, e, n->edge_tree) {
+ if(!e->reverse)
+ continue;
+
+ bool found = false;
+ for(struct addrinfo *aip = ai; aip; aip = aip->ai_next) {
+ if(!sockaddrcmp(&e->reverse->address, (sockaddr_t *)aip->ai_addr)) {
+ found = true;
+ break;
+ }
+ }
+ if(found)
+ continue;
+
+ struct addrinfo *nai = xzalloc(sizeof *nai);
+ if(ai)
+ ai->ai_next = nai;
+ ai = nai;
+ ai->ai_family = e->reverse->address.sa.sa_family;
+ ai->ai_socktype = SOCK_STREAM;
+ ai->ai_protocol = IPPROTO_TCP;
+ ai->ai_addrlen = SALEN(e->reverse->address.sa);
+ ai->ai_addr = xmalloc(ai->ai_addrlen);
+ memcpy(ai->ai_addr, &e->reverse->address, ai->ai_addrlen);
+ }
+
+ return ai;
+}
+
void setup_outgoing_connection(outgoing_t *outgoing) {
timeout_del(&outgoing->ev);
outgoing->cfg = lookup_config(outgoing->config_tree, "Address");
if(!outgoing->cfg) {
- logger(DEBUG_ALWAYS, LOG_ERR, "No address specified for %s", outgoing->name);
- return;
+ if(n)
+ outgoing->aip = outgoing->ai = get_known_addresses(n);
+ if(!outgoing->ai) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "No address known for %s", outgoing->name);
+ return;
+ }
}
do_outgoing_connection(outgoing);
// Check if we get many connections from the same host
static sockaddr_t prev_sa;
- static time_t prev_time;
static int tarpit = -1;
if(tarpit >= 0) {
tarpit = -1;
}
- if(prev_time == now.tv_sec && !sockaddrcmp_noport(&sa, &prev_sa)) {
- // if so, keep the connection open but ignore it completely.
- tarpit = fd;
- return;
+ if(!sockaddrcmp_noport(&sa, &prev_sa)) {
+ static int samehost_burst;
+ static int samehost_burst_time;
+
+ if(now.tv_sec - samehost_burst_time > samehost_burst)
+ samehost_burst = 0;
+ else
+ samehost_burst -= now.tv_sec - samehost_burst_time;
+
+ samehost_burst_time = now.tv_sec;
+ samehost_burst++;
+
+ if(samehost_burst > max_connection_burst) {
+ tarpit = fd;
+ return;
+ }
}
memcpy(&prev_sa, &sa, sizeof sa);
- prev_time = now.tv_sec;
// Check if we get many connections from different hosts
c = new_connection();
c->name = xstrdup("<unknown>");
+#ifndef DISABLE_LEGACY
c->outcipher = myself->connection->outcipher;
c->outdigest = myself->connection->outdigest;
+#endif
c->outmaclength = myself->connection->outmaclength;
c->outcompression = myself->connection->outcompression;
if(c->outgoing && c->outgoing->timeout == -1) {
c->outgoing = NULL;
logger(DEBUG_CONNECTIONS, LOG_INFO, "No more outgoing connection to %s", c->name);
- terminate_connection(c, c->status.active);
+ terminate_connection(c, c->edge);
}
}