Add --disable-zlib configure option
[tinc] / src / net_packet.c
index 63e3592..a438d3e 100644 (file)
@@ -1,7 +1,7 @@
 /*
     net_packet.c -- Handles in- and outgoing VPN packets
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2009 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2010 Guus Sliepen <guus@tinc-vpn.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
 #include <openssl/pem.h>
 #include <openssl/hmac.h>
 
+#ifdef HAVE_ZLIB
 #include <zlib.h>
+#endif
+
+#ifdef HAVE_LZO
 #include LZO1X_H
+#endif
 
 #include "avl_tree.h"
 #include "conf.h"
 #include "utils.h"
 #include "xalloc.h"
 
-#ifdef WSAEMSGSIZE
-#define EMSGSIZE WSAEMSGSIZE
-#endif
-
 int keylifetime = 0;
 int keyexpires = 0;
+#ifdef HAVE_LZO
 static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
+#endif
 
 static void send_udppacket(node_t *, vpn_packet_t *);
 
 #define MAX_SEQNO 1073741824
 
+// mtuprobes == 1..30: initial discovery, send bursts with 1 second interval
+// mtuprobes ==    31: sleep pinginterval seconds
+// mtuprobes ==    32: send 1 burst, sleep pingtimeout second
+// mtuprobes ==    33: no response from other side, restart PMTU discovery process
+
 void send_mtu_probe(node_t *n) {
        vpn_packet_t packet;
        int len, i;
+       int timeout = 1;
        
        n->mtuprobes++;
        n->mtuevent = NULL;
 
-       if(!n->status.reachable) {
-               logger(LOG_DEBUG, "Trying to send MTU probe to unreachable node %s (%s)", n->name, n->hostname);
+       if(!n->status.reachable || !n->status.validkey) {
+               ifdebug(TRAFFIC) logger(LOG_INFO, "Trying to send MTU probe to unreachable or rekeying node %s (%s)", n->name, n->hostname);
+               n->mtuprobes = 0;
                return;
        }
 
+       if(n->mtuprobes > 32) {
+               ifdebug(TRAFFIC) logger(LOG_INFO, "%s (%s) did not respond to UDP ping, restarting PMTU discovery", n->name, n->hostname);
+               n->mtuprobes = 1;
+               n->minmtu = 0;
+               n->maxmtu = MTU;
+       }
+
        if(n->mtuprobes >= 10 && !n->minmtu) {
                ifdebug(TRAFFIC) logger(LOG_INFO, "No response to MTU probes from %s (%s)", n->name, n->hostname);
+               n->mtuprobes = 0;
                return;
        }
 
+       if(n->mtuprobes == 30 || (n->mtuprobes < 30 && n->minmtu >= n->maxmtu)) {
+               if(n->minmtu > n->maxmtu)
+                       n->minmtu = n->maxmtu;
+               else
+                       n->maxmtu = n->minmtu;
+               n->mtu = n->minmtu;
+               ifdebug(TRAFFIC) logger(LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
+               n->mtuprobes = 31;
+       }
+
+       if(n->mtuprobes == 31) {
+               timeout = pinginterval;
+               goto end;
+       } else if(n->mtuprobes == 32) {
+               timeout = pingtimeout;
+       }
+
        for(i = 0; i < 3; i++) {
-               if(n->mtuprobes >= 30 || n->minmtu >= n->maxmtu) {
-                       n->mtu = n->minmtu;
-                       ifdebug(TRAFFIC) logger(LOG_INFO, "Fixing MTU of %s (%s) to %d after %d probes", n->name, n->hostname, n->mtu, n->mtuprobes);
-                       return;
-               }
+               if(n->maxmtu <= n->minmtu)
+                       len = n->maxmtu;
+               else
+                       len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
 
-               len = n->minmtu + 1 + rand() % (n->maxmtu - n->minmtu);
                if(len < 64)
                        len = 64;
                
@@ -96,10 +129,11 @@ void send_mtu_probe(node_t *n) {
                send_udppacket(n, &packet);
        }
 
+end:
        n->mtuevent = new_event();
        n->mtuevent->handler = (event_handler_t)send_mtu_probe;
        n->mtuevent->data = n;
-       n->mtuevent->time = now + 1;
+       n->mtuevent->time = now + timeout;
        event_add(n->mtuevent);
 }
 
@@ -108,48 +142,73 @@ void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 
        if(!packet->data[0]) {
                packet->data[0] = 1;
-               send_packet(n, packet);
+               send_udppacket(n, packet);
        } else {
+               if(len > n->maxmtu)
+                       len = n->maxmtu;
                if(n->minmtu < len)
                        n->minmtu = len;
+               if(n->mtuprobes > 30)
+                       n->mtuprobes = 30;
        }
 }
 
 static length_t compress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
-       if(level == 10) {
+       if(level == 0) {
+               memcpy(dest, source, len);
+               return len;
+       } else if(level == 10) {
+#ifdef HAVE_LZO
                lzo_uint lzolen = MAXSIZE;
                lzo1x_1_compress(source, len, dest, &lzolen, lzo_wrkmem);
                return lzolen;
+#else
+               return -1;
+#endif
        } else if(level < 10) {
+#ifdef HAVE_ZLIB
                unsigned long destlen = MAXSIZE;
                if(compress2(dest, &destlen, source, len, level) == Z_OK)
                        return destlen;
                else
+#endif
                        return -1;
        } else {
+#ifdef HAVE_LZO
                lzo_uint lzolen = MAXSIZE;
                lzo1x_999_compress(source, len, dest, &lzolen, lzo_wrkmem);
                return lzolen;
+#else
+               return -1;
+#endif
        }
        
        return -1;
 }
 
 static length_t uncompress_packet(uint8_t *dest, const uint8_t *source, length_t len, int level) {
-       if(level > 9) {
+       if(level == 0) {
+               memcpy(dest, source, len);
+               return len;
+       } else if(level > 9) {
+#ifdef HAVE_LZO
                lzo_uint lzolen = MAXSIZE;
                if(lzo1x_decompress_safe(source, len, dest, &lzolen, NULL) == LZO_E_OK)
                        return lzolen;
                else
+#endif
                        return -1;
-       } else {
+       }
+#ifdef HAVE_ZLIB
+       else {
                unsigned long destlen = MAXSIZE;
                if(uncompress(dest, &destlen, source, len) == Z_OK)
                        return destlen;
                else
                        return -1;
        }
-       
+#endif
+
        return -1;
 }
 
@@ -279,9 +338,6 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
 
        inpkt->priority = 0;
 
-       if(n->connection)
-               n->connection->last_ping_time = now;
-
        if(!inpkt->data[12] && !inpkt->data[13])
                mtu_probe_h(n, inpkt, origlen);
        else
@@ -325,10 +381,10 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
                                   "No valid key known yet for %s (%s), forwarding via TCP",
                                   n->name, n->hostname);
 
-               if(!n->status.waitingforkey)
+               if(n->last_req_key + 10 < now) {
                        send_req_key(n);
-
-               n->status.waitingforkey = true;
+                       n->last_req_key = now;
+               }
 
                send_tcppacket(n->nexthop->connection, origpkt);
 
@@ -337,10 +393,13 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
 
        if(n->options & OPTION_PMTU_DISCOVERY && inpkt->len > n->minmtu && (inpkt->data[12] | inpkt->data[13])) {
                ifdebug(TRAFFIC) logger(LOG_INFO,
-                               "Packet for %s (%s) larger than minimum MTU, forwarding via TCP",
-                               n->name, n->hostname);
+                               "Packet for %s (%s) larger than minimum MTU, forwarding via %s",
+                               n->name, n->hostname, n != n->nexthop ? n->nexthop->name : "TCP");
 
-               send_tcppacket(n->nexthop->connection, origpkt);
+               if(n != n->nexthop)
+                       send_packet(n->nexthop, origpkt);
+               else
+                       send_tcppacket(n->nexthop->connection, origpkt);
 
                return;
        }
@@ -414,14 +473,14 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
        }
 #endif
 
-       if((sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa))) < 0) {
-               if(errno == EMSGSIZE) {
+       if(sendto(listen_socket[sock].udp, (char *) &inpkt->seqno, inpkt->len, 0, &(n->address.sa), SALEN(n->address.sa)) < 0 && !sockwouldblock(sockerrno)) {
+               if(sockmsgsize(sockerrno)) {
                        if(n->maxmtu >= origlen)
                                n->maxmtu = origlen - 1;
                        if(n->mtu >= origlen)
                                n->mtu = origlen - 1;
                } else
-                       logger(LOG_ERR, "Error sending packet to %s (%s): %s", n->name, n->hostname, strerror(errno));
+                       logger(LOG_ERR, "Error sending packet to %s (%s): %s", n->name, n->hostname, sockstrerror(sockerrno));
        }
 
 end:
@@ -493,12 +552,16 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
        avl_node_t *node;
        edge_t *e;
        node_t *n = NULL;
+       static time_t last_hard_try = 0;
 
        for(node = edge_weight_tree->head; node; node = node->next) {
                e = node->data;
 
-               if(sockaddrcmp_noport(from, &e->address))
-                       continue;
+               if(sockaddrcmp_noport(from, &e->address)) {
+                       if(last_hard_try == now)
+                               continue;
+                       last_hard_try = now;
+               }
 
                if(!n)
                        n = e->to;
@@ -523,8 +586,8 @@ void handle_incoming_vpn_data(int sock) {
        pkt.len = recvfrom(sock, (char *) &pkt.seqno, MAXSIZE, 0, &from.sa, &fromlen);
 
        if(pkt.len < 0) {
-               if(errno != EAGAIN && errno != EINTR)
-                       logger(LOG_ERR, "Receiving packet failed: %s", strerror(errno));
+               if(!sockwouldblock(sockerrno))
+                       logger(LOG_ERR, "Receiving packet failed: %s", sockstrerror(sockerrno));
                return;
        }