Applied Martin Kihlgren's IdentityGenerosity patch,

simplified and renamed to StrictSource.

diff --git a/src/graph.c b/src/graph.c
index 3ed1d7213b3c7d35b3373eecdeaee9d3c03dbc55..3870c7090db9bc70894bbc6be30716223974f573 100644 (file)
--- a/src/graph.c
+++ b/src/graph.c
@@ -219,25 +219,8 @@ void sssp_bfs(void)
                                e->to->via = indirect ? n->via : e->to;
                                e->to->options = e->options;
 
-                               if(sockaddrcmp(&e->to->address, &e->address)) {
-                                       node = avl_unlink(node_udp_tree, e->to);
-                                       sockaddrfree(&e->to->address);
-                                       sockaddrcpy(&e->to->address, &e->address);
-
-                                       if(e->to->hostname)
-                                               free(e->to->hostname);
-
-                                       e->to->hostname = sockaddr2hostname(&e->to->address);
-                                       avl_insert_node(node_udp_tree, node);
-
-                                       if(e->to->options & OPTION_PMTU_DISCOVERY) {
-                                               e->to->mtuprobes = 0;
-                                               e->to->minmtu = 0;
-                                               e->to->maxmtu = MTU;
-                                               if(e->to->status.validkey)
-                                                       send_mtu_probe(e->to);
-                                       }
-                               }
+                               if(sockaddrcmp(&e->to->address, &e->address))
+                                       update_node_address(e->to, &e->address);
 
                                node = avl_alloc_node();
                                node->data = e->to;

diff --git a/src/net.h b/src/net.h
index 5b14553856ef52e8ffd890a380cbb6a5078e4036..90463eb225eaa8d708c5bce684b44d61911aa5d7 100644 (file)
--- a/src/net.h
+++ b/src/net.h
@@ -122,6 +122,7 @@ extern listen_socket_t listen_socket[MAXSOCKETS];
 extern int listen_sockets;
 extern int keyexpires;
 extern int keylifetime;
+extern bool strictsource;
 extern bool do_prune;
 extern bool do_purge;
 extern char *myport;

diff --git a/src/net_packet.c b/src/net_packet.c
index 255453e9b5cd23ecd7c62599b78bbf495575db46..ae5a8402a7af159ad3873b877854c2b286a0c485 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -54,6 +54,7 @@
 
 int keylifetime = 0;
 int keyexpires = 0;
+bool strictsource = true;
 EVP_CIPHER_CTX packet_ctx;
 static char lzo_wrkmem[LZO1X_999_MEM_COMPRESS > LZO1X_1_MEM_COMPRESS ? LZO1X_999_MEM_COMPRESS : LZO1X_1_MEM_COMPRESS];
 
@@ -167,6 +168,25 @@ static void receive_packet(node_t *n, vpn_packet_t *packet)
        route(n, packet);
 }
 
+static bool authenticate_udppacket(node_t *n, vpn_packet_t *inpkt) {
+       char hmac[EVP_MAX_MD_SIZE];
+
+       if(inpkt->len < sizeof(inpkt->seqno) + (myself->digest ? myself->maclength : 0))
+               return false;
+
+       /* Check the message authentication code */
+
+       if(myself->digest && myself->maclength) {
+               HMAC(myself->digest, myself->key, myself->keylength,
+                        (char *) &inpkt->seqno, inpkt->len - myself->maclength, hmac, NULL);
+
+               if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len - myself->maclength, myself->maclength))
+                       return false;
+       }
+
+       return true;
+}
+
 static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
 {
        vpn_packet_t pkt1, pkt2;
@@ -174,32 +194,17 @@ static void receive_udppacket(node_t *n, vpn_packet_t *inpkt)
        int nextpkt = 0;
        vpn_packet_t *outpkt = pkt[0];
        int outlen, outpad;
-       char hmac[EVP_MAX_MD_SIZE];
        int i;
 
        cp();
 
-       /* Check packet length */
-
-       if(inpkt->len < sizeof(inpkt->seqno) + myself->maclength) {
-               ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got too short packet from %s (%s)"),
-                                       n->name, n->hostname);
+       if(!authenticate_udppacket(n, inpkt)) {
+               ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"),
+                                          n->name, n->hostname);
                return;
        }
 
-       /* Check the message authentication code */
-
-       if(myself->digest && myself->maclength) {
-               inpkt->len -= myself->maclength;
-               HMAC(myself->digest, myself->key, myself->keylength,
-                        (char *) &inpkt->seqno, inpkt->len, hmac, NULL);
-
-               if(memcmp(hmac, (char *) &inpkt->seqno + inpkt->len, myself->maclength)) {
-                       ifdebug(TRAFFIC) logger(LOG_DEBUG, _("Got unauthenticated packet from %s (%s)"),
-                                          n->name, n->hostname);
-                       return;
-               }
-       }
+       inpkt->len -= myself->digest ? myself->maclength : 0;
 
        /* Decrypt the packet */
 
@@ -483,6 +488,7 @@ void handle_incoming_vpn_data(int sock)
        sockaddr_t from;
        socklen_t fromlen = sizeof(from);
        node_t *n;
+       static time_t lasttime = 0;
 
        cp();
 
@@ -497,10 +503,25 @@ void handle_incoming_vpn_data(int sock)
 
        n = lookup_node_udp(&from);
 
+       if(!n && !strictsource && myself->digest && myself->maclength && lasttime != now) {
+               avl_node_t *node;
+
+               lasttime = now;
+
+               for(node = node_tree->head; node; node = node->next) {
+                       n = node->data;
+
+                       if(authenticate_udppacket(n, &pkt)) {
+                               update_node_address(n, &from);
+                               logger(LOG_DEBUG, _("Updated address of node %s to %s"), n->name, n->hostname);
+                               break;
+                       }
+               }
+       }
+
        if(!n) {
                hostname = sockaddr2hostname(&from);
-               logger(LOG_WARNING, _("Received UDP packet from unknown source %s"),
-                          hostname);
+               logger(LOG_WARNING, _("Received UDP packet from unknown source %s"), hostname);
                free(hostname);
                return;
        }

diff --git a/src/net_setup.c b/src/net_setup.c
index aa2fbfbe9264b921b56553aca7fc150846c751e4..502e7b20b1dddc8a29f63ae78993f19677056707 100644 (file)
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -343,6 +343,8 @@ bool setup_myself(void)
 
        get_config_bool(lookup_config(config_tree, "Hostnames"), &hostnames);
 
+       get_config_bool(lookup_config(config_tree, "StrictSource"), &strictsource);
+
        /* Generate packet encryption key */
 
        if(get_config_string

diff --git a/src/node.c b/src/node.c
index 351991611b2cd2a3d692213b6866cb50df7c4a25..79320e7101f6f5a098d6957d349a3197e4d05f50 100644 (file)
--- a/src/node.c
+++ b/src/node.c
@@ -150,6 +150,28 @@ void node_del(node_t *n)
        avl_delete(node_udp_tree, n);
 }
 
+void update_node_address(node_t *n, const sockaddr_t address) {
+       avl_node_t *node;
+
+       node = avl_unlink(node_udp_tree, n);
+       sockaddrfree(&n->address);
+       sockaddrcpy(&n->address, &address);
+
+       if(n->hostname)
+               free(n->hostname);
+
+       n->hostname = sockaddr2hostname(&n->address);
+       avl_insert_node(node_udp_tree, node);
+
+       if(n->options & OPTION_PMTU_DISCOVERY) {
+               n->mtuprobes = 0;
+               n->minmtu = 0;
+               n->maxmtu = MTU;
+               if(n->status.validkey)
+                       send_mtu_probe(n);
+       }
+}
+
 node_t *lookup_node(char *name)
 {
        node_t n = {0};

diff --git a/src/node.h b/src/node.h
index dd9c7a12f1ace0858b1a24c28b91d3599fe8dd17..6dc7338baabb03a7500f51f3eab983b0138d9d23 100644 (file)
--- a/src/node.h
+++ b/src/node.h
@@ -90,6 +90,7 @@ extern node_t *new_node(void) __attribute__ ((__malloc__));
 extern void free_node(node_t *);
 extern void node_add(node_t *);
 extern void node_del(node_t *);
+extern void update_node_udpaddress(node_t *, const sockaddr_t *);
 extern node_t *lookup_node(char *);
 extern node_t *lookup_node_udp(const sockaddr_t *);
 extern void dump_nodes(void);