Replace the connection_tree with a connection_list.
[tinc] / src / net_packet.c
index ac3b0cc..c9a6663 100644 (file)
@@ -1,7 +1,7 @@
 /*
     net_packet.c -- Handles in- and outgoing VPN packets
     Copyright (C) 1998-2005 Ivo Timmermans,
-                  2000-2011 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2012 Guus Sliepen <guus@tinc-vpn.org>
                   2010      Timothy Redaelli <timothy@redaelli.eu>
                   2010      Brandon Black <blblack@gmail.com>
 
@@ -36,7 +36,6 @@
 #include LZO1X_H
 #endif
 
-#include "splay_tree.h"
 #include "cipher.h"
 #include "conf.h"
 #include "connection.h"
@@ -252,6 +251,9 @@ static void receive_packet(node_t *n, vpn_packet_t *packet) {
 }
 
 static bool try_mac(node_t *n, const vpn_packet_t *inpkt) {
+       if(n->status.sptps)
+               return sptps_verify_datagram(&n->sptps, (char *)&inpkt->seqno, inpkt->len);
+
        if(!digest_active(&n->indigest) || inpkt->len < sizeof inpkt->seqno + digest_length(&n->indigest))
                return false;
 
@@ -265,6 +267,11 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
        vpn_packet_t *outpkt = pkt[0];
        size_t outlen;
 
+       if(n->status.sptps) {
+               sptps_receive_data(&n->sptps, (char *)&inpkt->seqno, inpkt->len);
+               return;
+       }
+
        if(!cipher_active(&n->incipher)) {
                logger(DEBUG_TRAFFIC, LOG_DEBUG, "Got packet from %s (%s) but he hasn't got our key yet",
                                        n->name, n->hostname);
@@ -380,6 +387,52 @@ void receive_tcppacket(connection_t *c, const char *buffer, int len) {
        receive_packet(c->node, &outpkt);
 }
 
+static void send_sptps_packet(node_t *n, vpn_packet_t *origpkt) {
+       if(!n->status.validkey) {
+               logger(DEBUG_TRAFFIC, LOG_INFO, "No valid key known yet for %s (%s)", n->name, n->hostname);
+               if(!n->status.waitingforkey)
+                       send_req_key(n);
+               else if(n->last_req_key + 10 < time(NULL)) {
+                       sptps_stop(&n->sptps);
+                       n->status.waitingforkey = false;
+                       send_req_key(n);
+               }
+               return;
+       }
+
+       uint8_t type = 0;
+       int offset = 0;
+
+       if(!(origpkt->data[12] | origpkt->data[13])) {
+               sptps_send_record(&n->sptps, PKT_PROBE, (char *)origpkt->data, origpkt->len);
+               return;
+       }
+
+       if(routing_mode == RMODE_ROUTER)
+               offset = 14;
+       else
+               type = PKT_MAC;
+
+       if(origpkt->len < offset)
+               return;
+
+       vpn_packet_t outpkt;
+
+       if(n->outcompression) {
+               int len = compress_packet(outpkt.data + offset, origpkt->data + offset, origpkt->len - offset, n->outcompression);
+               if(len < 0) {
+                       logger(DEBUG_TRAFFIC, LOG_ERR, "Error while compressing packet to %s (%s)", n->name, n->hostname);
+               } else if(len < origpkt->len - offset) {
+                       outpkt.len = len + offset;
+                       origpkt = &outpkt;
+                       type |= PKT_COMPRESSED;
+               }
+       }
+
+       sptps_send_record(&n->sptps, type, (char *)origpkt->data + offset, origpkt->len - offset);
+       return;
+}
+
 static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
        vpn_packet_t pkt1, pkt2;
        vpn_packet_t *pkt[] = { &pkt1, &pkt2, &pkt1, &pkt2 };
@@ -390,14 +443,17 @@ static void send_udppacket(node_t *n, vpn_packet_t *origpkt) {
        size_t outlen;
 #if defined(SOL_IP) && defined(IP_TOS)
        static int priority = 0;
-       int origpriority = origpkt->priority;
 #endif
+       int origpriority = origpkt->priority;
 
        if(!n->status.reachable) {
                logger(DEBUG_TRAFFIC, LOG_INFO, "Trying to send UDP packet to unreachable node %s (%s)", n->name, n->hostname);
                return;
        }
 
+       if(n->status.sptps)
+               return send_sptps_packet(n, origpkt);
+
        /* Make sure we have a valid key */
 
        if(!n->status.validkey) {
@@ -531,6 +587,120 @@ end:
        origpkt->len = origlen;
 }
 
+bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+       node_t *to = handle;
+
+       if(type >= SPTPS_HANDSHAKE
+                       || ((myself->options | to->options) & OPTION_TCPONLY)
+                       || (type != PKT_PROBE && len > to->minmtu)) {
+               char buf[len * 4 / 3 + 5];
+               b64encode(data, buf, len);
+               if(!to->status.validkey)
+                       return send_request(to->nexthop->connection, "%d %s %s %s -1 -1 -1 %d", ANS_KEY, myself->name, to->name, buf, myself->incompression);
+               else
+                       return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, type >= SPTPS_HANDSHAKE ? REQ_SPTPS : REQ_PACKET, buf);
+       }
+
+       /* Send the packet */
+
+       struct sockaddr *sa;
+       socklen_t sl;
+       int sock;
+
+       sa = &(to->address.sa);
+       sl = SALEN(to->address.sa);
+       sock = to->sock;
+
+       if(sendto(listen_socket[sock].udp, data, len, 0, sa, sl) < 0 && !sockwouldblock(sockerrno)) {
+               if(sockmsgsize(sockerrno)) {
+                       if(to->maxmtu >= len)
+                               to->maxmtu = len - 1;
+                       if(to->mtu >= len)
+                               to->mtu = len - 1;
+               } else {
+                       logger(DEBUG_TRAFFIC, LOG_WARNING, "Error sending UDP SPTPS packet to %s (%s): %s", to->name, to->hostname, sockstrerror(sockerrno));
+                       return false;
+               }
+       }
+
+       return true;
+}
+
+bool receive_sptps_record(void *handle, uint8_t type, const char *data, uint16_t len) {
+       node_t *from = handle;
+
+       if(type == SPTPS_HANDSHAKE) {
+               from->status.validkey = true;
+               from->status.waitingforkey = false;
+               logger(DEBUG_META, LOG_INFO, "SPTPS key exchange with %s (%s) succesful", from->name, from->hostname);
+               return true;
+       }
+
+       if(len > MTU) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Packet from %s (%s) larger than maximum supported size (%d > %d)", from->name, from->hostname, len, MTU);
+               return false;
+       }
+
+       vpn_packet_t inpkt;
+
+       if(type == PKT_PROBE) {
+               inpkt.len = len;
+               memcpy(inpkt.data, data, len);
+               mtu_probe_h(from, &inpkt, len);
+               return true;
+       }
+
+       if(type & ~(PKT_COMPRESSED | PKT_MAC)) {
+               logger(DEBUG_ALWAYS, LOG_ERR, "Unexpected SPTPS record type %d len %d from %s (%s)", type, len, from->name, from->hostname);
+               return false;
+       }
+
+       /* Check if we have the headers we need */
+       if(routing_mode != RMODE_ROUTER && !(type & PKT_MAC)) {
+               logger(DEBUG_TRAFFIC, LOG_ERR, "Received packet from %s (%s) without MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+               return false;
+       } else if(routing_mode == RMODE_ROUTER && (type & PKT_MAC)) {
+               logger(DEBUG_TRAFFIC, LOG_WARNING, "Received packet from %s (%s) with MAC header (maybe Mode is not set correctly)", from->name, from->hostname);
+       }
+
+       int offset = (type & PKT_MAC) ? 0 : 14;
+       if(type & PKT_COMPRESSED) {
+               len = uncompress_packet(inpkt.data + offset, (const uint8_t *)data, len, from->incompression);
+               if(len < 0) {
+                       return false;
+               } else {
+                       inpkt.len = len + offset;
+               }
+               if(inpkt.len > MAXSIZE)
+                       abort();
+       } else {
+               memcpy(inpkt.data + offset, data, len);
+               inpkt.len = len + offset;
+       }
+
+       /* Generate the Ethernet packet type if necessary */
+       if(offset) {
+               switch(inpkt.data[14] >> 4) {
+                       case 4:
+                               inpkt.data[12] = 0x08;
+                               inpkt.data[13] = 0x00;
+                               break;
+                       case 6:
+                               inpkt.data[12] = 0x86;
+                               inpkt.data[13] = 0xDD;
+                               break;
+                       default:
+                               logger(DEBUG_TRAFFIC, LOG_ERR,
+                                                  "Unknown IP version %d while reading packet from %s (%s)",
+                                                  inpkt.data[14] >> 4, from->name, from->hostname);
+                               return false;
+               }
+       }
+
+       receive_packet(from, &inpkt);
+       return true;
+}
+
 /*
   send a packet to the given vpn ip.
 */
@@ -558,6 +728,11 @@ void send_packet(node_t *n, vpn_packet_t *packet) {
        n->out_packets++;
        n->out_bytes += packet->len;
 
+       if(n->status.sptps) {
+               send_sptps_packet(n, packet);
+               return;
+       }
+
        via = (packet->priority == -1 || n->via == myself) ? n->nexthop : n->via;
 
        if(via != n)
@@ -574,26 +749,49 @@ void send_packet(node_t *n, vpn_packet_t *packet) {
 /* Broadcast a packet using the minimum spanning tree */
 
 void broadcast_packet(const node_t *from, vpn_packet_t *packet) {
-       splay_node_t *node;
-       connection_t *c;
+       // Always give ourself a copy of the packet.
+       if(from != myself)
+               send_packet(myself, packet);
+
+       // In TunnelServer mode, do not forward broadcast packets.
+        // The MST might not be valid and create loops.
+       if(tunnelserver || broadcast_mode == BMODE_NONE)
+               return;
 
        logger(DEBUG_TRAFFIC, LOG_INFO, "Broadcasting packet of %d bytes from %s (%s)",
                           packet->len, from->name, from->hostname);
 
-       if(from != myself) {
-               send_packet(myself, packet);
+       switch(broadcast_mode) {
+               // In MST mode, broadcast packets travel via the Minimum Spanning Tree.
+               // This guarantees all nodes receive the broadcast packet, and
+               // usually distributes the sending of broadcast packets over all nodes.
+               case BMODE_MST:
+                       for(list_node_t *node = connection_list->head, *next; node; node = next) {
+                               next = node->next;
+                               connection_t *c = node->data;
+
+                               if(c->status.active && c->status.mst && c != from->nexthop->connection)
+                                       send_packet(c->node, packet);
+                       }
+                       break;
 
-               // In TunnelServer mode, do not forward broadcast packets.
-                // The MST might not be valid and create loops.
-               if(tunnelserver)
-                       return;
-       }
+               // In direct mode, we send copies to each node we know of.
+               // However, this only reaches nodes that can be reached in a single hop.
+               // We don't have enough information to forward broadcast packets in this case.
+               case BMODE_DIRECT:
+                       if(from != myself)
+                               break;
 
-       for(node = connection_tree->head; node; node = node->next) {
-               c = node->data;
+                       for(splay_node_t *node = node_tree->head; node; node = node->next) {
+                               node_t *n = node->data;
+
+                               if(n->status.reachable && ((n->via == myself && n->nexthop == n) || n->via == n))
+                                       send_packet(n, packet);
+                       }
+                       break;
 
-               if(c->status.active && c->status.mst && c != from->nexthop->connection)
-                       send_packet(c->node, packet);
+               default:
+                       break;
        }
 }
 
@@ -608,7 +806,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
        for(node = edge_weight_tree->head; node; node = node->next) {
                e = node->data;
 
-               if(e->to == myself)
+               if(!e->to->status.reachable || e->to == myself)
                        continue;
 
                if(sockaddrcmp_noport(from, &e->address)) {
@@ -634,7 +832,7 @@ static node_t *try_harder(const sockaddr_t *from, const vpn_packet_t *pkt) {
 void handle_incoming_vpn_data(int sock, short events, void *data) {
        vpn_packet_t pkt;
        char *hostname;
-       sockaddr_t from;
+       sockaddr_t from = {{0}};
        socklen_t fromlen = sizeof from;
        node_t *n;
        int len;