Remove texi2html rule in docs/Makefile.

[tinc] / src / net_socket.c

diff --git a/src/net_socket.c b/src/net_socket.c
index 0ba2bf3..ded9224 100644 (file)
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -45,6 +45,7 @@ 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;
@@ -294,10 +295,7 @@ void retry_outgoing(outgoing_t *outgoing) {
 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);
@@ -352,6 +350,9 @@ static void do_outgoing_pipe(connection_t *c, char *command) {
 }
 
 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) {
@@ -380,7 +381,7 @@ static void handle_meta_io(void *data, int flags) {
 
                int result;
                socklen_t len = sizeof result;
-               getsockopt(c->socket, SOL_SOCKET, SO_ERROR, &result, &len);
+               getsockopt(c->socket, SOL_SOCKET, SO_ERROR, (void *)&result, &len);
 
                if(!result)
                        finish_connecting(c);
@@ -459,6 +460,7 @@ 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) {
@@ -507,7 +509,7 @@ 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);
 
@@ -560,6 +562,47 @@ void handle_new_meta_connection(void *data, int flags) {
 
        sockaddrunmap(&sa);
 
+       // 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) {
+               closesocket(tarpit);
+               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;
+       }
+
+       memcpy(&prev_sa, &sa, sizeof sa);
+       prev_time = now.tv_sec;
+
+       // 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;
@@ -570,7 +613,7 @@ void handle_new_meta_connection(void *data, int flags) {
        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);
 
@@ -609,7 +652,7 @@ void handle_new_unix_connection(void *data, int flags) {
        c->address = sa;
        c->hostname = xstrdup("localhost port unix");
        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);
 
@@ -673,7 +716,7 @@ 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);