/*
net_socket.c -- Handle various kinds of sockets.
Copyright (C) 1998-2005 Ivo Timmermans,
- 2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+ 2000-2016 Guus Sliepen <guus@tinc-vpn.org>
2006 Scott Lamb <slamb@slamb.org>
2009 Florian Forster <octo@verplant.org>
#include "conf.h"
#include "connection.h"
+#include "control_common.h"
#include "list.h"
#include "logger.h"
#include "meta.h"
+#include "names.h"
#include "net.h"
#include "netutl.h"
#include "protocol.h"
#include "utils.h"
#include "xalloc.h"
-/* Needed on Mac OS/X */
-#ifndef SOL_TCP
-#define SOL_TCP IPPROTO_TCP
-#endif
-
int addressfamily = AF_UNSPEC;
int maxtimeout = 900;
int seconds_till_retry = 5;
-int udp_rcvbuf = 0;
-int udp_sndbuf = 0;
+int udp_rcvbuf = 1024 * 1024;
+int udp_sndbuf = 1024 * 1024;
+int max_connection_burst = 100;
listen_socket_t listen_socket[MAXSOCKETS];
int listen_sockets;
+#ifndef HAVE_MINGW
+io_t unix_socket;
+#endif
list_t *outgoing_list = NULL;
/* Setup sockets */
}
#endif
-#if defined(SOL_TCP) && defined(TCP_NODELAY)
+#if defined(IPPROTO_TCP) && defined(TCP_NODELAY)
option = 1;
- setsockopt(c->socket, SOL_TCP, TCP_NODELAY, (void *)&option, sizeof option);
+ setsockopt(c->socket, IPPROTO_TCP, TCP_NODELAY, (void *)&option, sizeof option);
#endif
-#if defined(SOL_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
+#if defined(IPPROTO_IP) && defined(IP_TOS) && defined(IPTOS_LOWDELAY)
option = IPTOS_LOWDELAY;
- setsockopt(c->socket, SOL_IP, IP_TOS, (void *)&option, sizeof option);
+ setsockopt(c->socket, IPPROTO_IP, IP_TOS, (void *)&option, sizeof option);
+#endif
+
+#if defined(IPPROTO_IPV6) && defined(IPV6_TCLASS) && defined(IPTOS_LOWDELAY)
+ option = IPTOS_LOWDELAY;
+ setsockopt(c->socket, IPPROTO_IPV6, IPV6_TCLASS, (void *)&option, sizeof option);
#endif
}
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;
option = 1;
setsockopt(nfd, SOL_SOCKET, SO_REUSEADDR, (void *)&option, sizeof option);
-#if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
+#if defined(IPPROTO_IPV6) && defined(IPV6_V6ONLY)
if(sa->sa.sa_family == AF_INET6)
- setsockopt(nfd, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
#endif
if(get_config_string
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)
#define IP_DONTFRAGMENT IP_DONTFRAG
#endif
-#if defined(SOL_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
+#if defined(IPPROTO_IP) && defined(IP_MTU_DISCOVER) && defined(IP_PMTUDISC_DO)
if(myself->options & OPTION_PMTU_DISCOVERY) {
option = IP_PMTUDISC_DO;
- setsockopt(nfd, SOL_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option));
+ setsockopt(nfd, IPPROTO_IP, IP_MTU_DISCOVER, (void *)&option, sizeof(option));
}
#elif defined(IPPROTO_IP) && defined(IP_DONTFRAGMENT)
if(myself->options & OPTION_PMTU_DISCOVERY) {
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)
+#if defined(IPPROTO_IPV6) && defined(IPV6_MTU_DISCOVER) && defined(IPV6_PMTUDISC_DO)
if(myself->options & OPTION_PMTU_DISCOVERY) {
option = IPV6_PMTUDISC_DO;
- setsockopt(nfd, SOL_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option));
+ setsockopt(nfd, IPPROTO_IPV6, IPV6_MTU_DISCOVER, (void *)&option, sizeof(option));
}
#elif defined(IPPROTO_IPV6) && defined(IPV6_DONTFRAG)
if(myself->options & OPTION_PMTU_DISCOVERY) {
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)) {
return nfd;
} /* int setup_vpn_in_socket */
-static void retry_outgoing_handler(int fd, short events, void *data) {
+static void retry_outgoing_handler(void *data) {
setup_outgoing_connection(data);
}
if(outgoing->timeout > maxtimeout)
outgoing->timeout = maxtimeout;
- timeout_set(&outgoing->ev, retry_outgoing_handler, outgoing);
- event_add(&outgoing->ev, &(struct timeval){outgoing->timeout, 0});
+ timeout_add(&outgoing->ev, retry_outgoing_handler, outgoing, &(struct timeval){outgoing->timeout, rand() % 100000});
- logger(DEBUG_CONNECTIONS, LOG_NOTICE,
- "Trying to re-establish outgoing connection in %d seconds",
- outgoing->timeout);
+ logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Trying to re-establish outgoing connection in %d seconds", outgoing->timeout);
}
void finish_connecting(connection_t *c) {
logger(DEBUG_CONNECTIONS, LOG_INFO, "Connected to %s (%s)", c->name, c->hostname);
- if(proxytype != PROXY_EXEC)
- configure_tcp(c);
-
- c->last_ping_time = time(NULL);
+ c->last_ping_time = now.tv_sec;
c->status.connecting = false;
send_id(c);
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;
}
#endif
}
-static void handle_meta_write(int sock, short events, void *data) {
- connection_t *c = data;
+static void handle_meta_write(connection_t *c) {
+ if(c->outbuf.len <= c->outbuf.offset)
+ 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;
}
buffer_read(&c->outbuf, outlen);
- if(!c->outbuf.len && event_initialized(&c->outevent))
- event_del(&c->outevent);
+ if(!c->outbuf.len)
+ io_set(&c->io, IO_READ);
+}
+
+static void handle_meta_io(void *data, int flags) {
+ connection_t *c = data;
+
+ if(c->status.connecting) {
+ /*
+ 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)
+ handle_meta_write(c);
+ else
+ handle_meta_connection_data(c);
}
+static void free_known_addresses(struct addrinfo *ai) {
+ for(struct addrinfo *aip = ai, *next; aip; aip = next) {
+ next = aip->ai_next;
+ free(aip);
+ }
+}
bool do_outgoing_connection(outgoing_t *outgoing) {
char *address, *port, *space;
int result;
begin:
- if(!outgoing->ai) {
+ if(!outgoing->ai && !outgoing->kai) {
if(!outgoing->cfg) {
logger(DEBUG_CONNECTIONS, LOG_ERR, "Could not set up a meta connection to %s", outgoing->name);
retry_outgoing(outgoing);
if(outgoing->ai)
freeaddrinfo(outgoing->ai);
outgoing->ai = NULL;
+
+ if(outgoing->kai)
+ free_known_addresses(outgoing->kai);
+ outgoing->kai = NULL;
+
goto begin;
}
}
logger(DEBUG_CONNECTIONS, LOG_INFO, "Using proxy at %s port %s", proxyhost, proxyport);
c->socket = socket(proxyai->ai_family, SOCK_STREAM, IPPROTO_TCP);
+ configure_tcp(c);
}
if(c->socket == -1) {
#endif
if(proxytype != PROXY_EXEC) {
-#if defined(SOL_IPV6) && defined(IPV6_V6ONLY)
+#if defined(IPPROTO_IPV6) && defined(IPV6_V6ONLY)
int option = 1;
if(c->address.sa.sa_family == AF_INET6)
- setsockopt(c->socket, SOL_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
+ setsockopt(c->socket, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&option, sizeof option);
#endif
bind_to_interface(c->socket);
+ bind_to_address(c);
}
/* Connect */
} else if(proxytype == PROXY_EXEC) {
result = 0;
} else {
+ if(!proxyai)
+ abort();
result = connect(c->socket, proxyai->ai_addr, proxyai->ai_addrlen);
freeaddrinfo(proxyai);
}
/* Now that there is a working socket, fill in the rest and register this connection. */
+ c->last_ping_time = time(NULL);
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 = time(NULL);
+ c->last_ping_time = now.tv_sec;
connection_add(c);
- event_set(&c->inevent, c->socket, EV_READ | EV_PERSIST, handle_meta_connection_data, c);
- event_set(&c->outevent, c->socket, EV_WRITE | EV_PERSIST, handle_meta_write, c);
- event_add(&c->inevent, NULL);
+ io_add(&c->io, handle_meta_io, c, c->socket, IO_READ|IO_WRITE);
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;
+ struct addrinfo *oai = 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;
+
+ oai = ai;
+ ai = xzalloc(sizeof *ai);
+ 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);
+ ai->ai_next = oai;
+ }
+
+ return ai;
+}
+
void setup_outgoing_connection(outgoing_t *outgoing) {
- if(event_initialized(&outgoing->ev))
- event_del(&outgoing->ev);
+ timeout_del(&outgoing->ev);
node_t *n = lookup_node(outgoing->name);
if(n && n->connection) {
logger(DEBUG_CONNECTIONS, LOG_INFO, "Already connected to %s", outgoing->name);
-
- n->connection->outgoing = outgoing;
- return;
+ if(!n->connection->outgoing) {
+ n->connection->outgoing = outgoing;
+ return;
+ } else {
+ goto remove;
+ }
}
init_configuration(&outgoing->config_tree);
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->kai = get_known_addresses(n);
+ if(!outgoing->kai) {
+ logger(DEBUG_ALWAYS, LOG_DEBUG, "No address known for %s", outgoing->name);
+ goto remove;
+ }
}
do_outgoing_connection(outgoing);
+ return;
+
+remove:
+ list_delete(outgoing_list, outgoing);
}
/*
accept a new tcp connect and create a
new connection
*/
-void handle_new_meta_connection(int sock, short events, void *data) {
+void handle_new_meta_connection(void *data, int flags) {
+ listen_socket_t *l = data;
connection_t *c;
sockaddr_t sa;
int fd;
socklen_t len = sizeof sa;
- fd = accept(sock, &sa.sa, &len);
+ fd = accept(l->tcp.fd, &sa.sa, &len);
if(fd < 0) {
logger(DEBUG_ALWAYS, LOG_ERR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
sockaddrunmap(&sa);
+ // Check if we get many connections from the same host
+
+ static sockaddr_t prev_sa;
+ static int tarpit = -1;
+
+ if(tarpit >= 0) {
+ closesocket(tarpit);
+ tarpit = -1;
+ }
+
+ 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);
+
+ // Check if we get many connections from different hosts
+
+ static int connection_burst;
+ static int connection_burst_time;
+
+ if(now.tv_sec - connection_burst_time > connection_burst)
+ connection_burst = 0;
+ else
+ connection_burst -= now.tv_sec - connection_burst_time;
+
+ connection_burst_time = now.tv_sec;
+ connection_burst++;
+
+ if(connection_burst >= max_connection_burst) {
+ connection_burst = max_connection_burst;
+ tarpit = fd;
+ return;
+ }
+
+ // Accept the new connection
+
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;
c->address = sa;
c->hostname = sockaddr2hostname(&sa);
c->socket = fd;
- c->last_ping_time = time(NULL);
+ c->last_ping_time = now.tv_sec;
logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection from %s", c->hostname);
- event_set(&c->inevent, c->socket, EV_READ | EV_PERSIST, handle_meta_connection_data, c);
- event_set(&c->outevent, c->socket, EV_WRITE | EV_PERSIST, handle_meta_write, c);
- event_add(&c->inevent, NULL);
+ io_add(&c->io, handle_meta_io, c, c->socket, IO_READ);
configure_tcp(c);
send_id(c);
}
+#ifndef HAVE_MINGW
+/*
+ accept a new UNIX socket connection
+*/
+void handle_new_unix_connection(void *data, int flags) {
+ io_t *io = data;
+ connection_t *c;
+ sockaddr_t sa;
+ int fd;
+ socklen_t len = sizeof sa;
+
+ fd = accept(io->fd, &sa.sa, &len);
+
+ if(fd < 0) {
+ logger(DEBUG_ALWAYS, LOG_ERR, "Accepting a new connection failed: %s", sockstrerror(sockerrno));
+ return;
+ }
+
+ sockaddrunmap(&sa);
+
+ c = new_connection();
+ c->name = xstrdup("<control>");
+ c->address = sa;
+ c->hostname = xstrdup("localhost port unix");
+ c->socket = fd;
+ c->last_ping_time = now.tv_sec;
+
+ logger(DEBUG_CONNECTIONS, LOG_NOTICE, "Connection from %s", c->hostname);
+
+ io_add(&c->io, handle_meta_io, c, c->socket, IO_READ);
+
+ connection_add(c);
+
+ c->allow_request = ID;
+
+ send_id(c);
+}
+#endif
+
static void free_outgoing(outgoing_t *outgoing) {
- if(event_initialized(&outgoing->ev))
- event_del(&outgoing->ev);
+ timeout_del(&outgoing->ev);
if(outgoing->ai)
freeaddrinfo(outgoing->ai);
+ if(outgoing->kai)
+ free_known_addresses(outgoing->kai);
+
if(outgoing->config_tree)
exit_configuration(&outgoing->config_tree);
continue;
}
+ if(!strcmp(name, myself->name)) {
+ free(name);
+ continue;
+ }
+
bool found = false;
for list_each(outgoing_t, outgoing, outgoing_list) {
}
if(!found) {
- outgoing_t *outgoing = xmalloc_and_zero(sizeof *outgoing);
+ outgoing_t *outgoing = xzalloc(sizeof *outgoing);
outgoing->name = name;
list_insert_tail(outgoing_list, outgoing);
setup_outgoing_connection(outgoing);
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);
}
}