Add the ListenAddress option.
[tinc] / src / net_socket.c
index ce1e3aa..30b36a7 100644 (file)
@@ -1,7 +1,7 @@
 /*
     net_socket.c -- Handle various kinds of sockets.
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2013 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"
@@ -43,9 +45,13 @@ int maxtimeout = 900;
 int seconds_till_retry = 5;
 int udp_rcvbuf = 0;
 int udp_sndbuf = 0;
+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 */
@@ -107,6 +113,34 @@ static bool bind_to_interface(int sd) {
        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", strerror(errno));
+               return false;
+       }
+
+       return true;
+}
+
 int setup_listen_socket(const sockaddr_t *sa) {
        int nfd;
        char *addrstr;
@@ -271,7 +305,7 @@ int setup_vpn_in_socket(const sockaddr_t *sa) {
        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);
 }
 
@@ -281,21 +315,15 @@ void retry_outgoing(outgoing_t *outgoing) {
        if(outgoing->timeout > maxtimeout)
                outgoing->timeout = maxtimeout;
 
-       timeout_set(&outgoing->ev, retry_outgoing_handler, outgoing);
-       event_add(&outgoing->ev, &(struct timeval){outgoing->timeout, rand() % 100000});
+       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);
@@ -349,8 +377,9 @@ static void do_outgoing_pipe(connection_t *c, char *command) {
 #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) {
@@ -368,10 +397,34 @@ static void handle_meta_write(int sock, short events, void *data) {
        }
 
        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) {
+               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);
+                       return;
+               }
+       }
+
+       if(flags & IO_WRITE)
+               handle_meta_write(c);
+       else
+               handle_meta_connection_data(c);
+}
 
 bool do_outgoing_connection(outgoing_t *outgoing) {
        char *address, *port, *space;
@@ -435,6 +488,7 @@ 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) {
@@ -455,6 +509,7 @@ begin:
 #endif
 
                bind_to_interface(c->socket);
+               bind_to_address(c);
        }
 
        /* Connect */
@@ -483,20 +538,17 @@ begin:
        c->outdigest = myself->connection->outdigest;
        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;
 }
 
 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);
 
@@ -523,13 +575,14 @@ void setup_outgoing_connection(outgoing_t *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));
@@ -538,6 +591,57 @@ void handle_new_meta_connection(int sock, short events, void *data) {
 
        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>");
        c->outcipher = myself->connection->outcipher;
@@ -548,13 +652,11 @@ void handle_new_meta_connection(int sock, short events, void *data) {
        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);
 
@@ -564,9 +666,47 @@ void handle_new_meta_connection(int sock, short events, void *data) {
        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);
@@ -615,7 +755,7 @@ void try_outgoing_connections(void) {
                }
 
                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);