tinc-gui: Reformat codebase according to PEP8
[tinc] / src / protocol_key.c
index aaf0f33..b409a35 100644 (file)
@@ -36,6 +36,7 @@
 static bool mykeyused = false;
 
 void send_key_changed(void) {
+#ifndef DISABLE_LEGACY
        send_request(everyone, "%d %x %s", KEY_CHANGED, rand(), myself->name);
 
        /* Immediately send new keys to directly connected nodes to keep UDP mappings alive */
@@ -43,6 +44,7 @@ void send_key_changed(void) {
        for list_each(connection_t, c, connection_list)
                if(c->edge && c->node && c->node->status.reachable && !c->node->status.sptps)
                        send_ans_key(c->node);
+#endif
 
        /* Force key exchange for connections using SPTPS */
 
@@ -87,9 +89,13 @@ bool key_changed_h(connection_t *c, const char *request) {
        return true;
 }
 
+static bool send_sptps_data_myself(void *handle, uint8_t type, const void *data, size_t len) {
+       return send_sptps_data(handle, myself, type, data, len);
+}
+
 static bool send_initial_sptps_data(void *handle, uint8_t type, const void *data, size_t len) {
        node_t *to = handle;
-       to->sptps.send_data = send_sptps_data;
+       to->sptps.send_data = send_sptps_data_myself;
        char buf[len * 4 / 3 + 5];
        b64encode(data, buf, len);
        return send_request(to->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, to->name, REQ_KEY, buf);
@@ -103,9 +109,6 @@ bool send_req_key(node_t *to) {
                        return true;
                }
 
-               if(to->sptps.label)
-                       logger(DEBUG_ALWAYS, LOG_DEBUG, "send_req_key(%s) called while sptps->label != NULL!", to->name);
-
                char label[25 + strlen(myself->name) + strlen(to->name)];
                snprintf(label, sizeof label, "tinc UDP key expansion %s %s", myself->name, to->name);
                sptps_stop(&to->sptps);
@@ -121,7 +124,52 @@ bool send_req_key(node_t *to) {
 
 /* REQ_KEY is overloaded to allow arbitrary requests to be routed between two nodes. */
 
-static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, int reqno) {
+static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, node_t *to, int reqno) {
+       /* If this is a SPTPS packet, see if sending UDP info helps.
+          Note that we only do this if we're the destination or the static relay;
+          otherwise every hop would initiate its own UDP info message, resulting in elevated chatter. */
+       if((reqno == REQ_KEY || reqno == SPTPS_PACKET) && to->via == myself)
+               send_udp_info(myself, from);
+
+       if(reqno == SPTPS_PACKET) {
+               /* This is a SPTPS data packet. */
+
+               char buf[MAX_STRING_SIZE];
+               int len;
+               if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
+                       logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s) to %s (%s): %s", "SPTPS_PACKET", from->name, from->hostname, to->name, to->hostname, "invalid SPTPS data");
+                       return true;
+               }
+
+               if(to != myself) {
+                       /* We don't just forward the request, because we want to use UDP if it's available. */
+                       send_sptps_data(to, from, 0, buf, len);
+                       try_tx(to, true);
+               } else {
+                       /* The packet is for us */
+                       if(!sptps_receive_data(&from->sptps, buf, len)) {
+                               /* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+                                  so let's restart SPTPS in case that helps. But don't do that too often
+                                  to prevent storms. */
+                               if(from->last_req_key < now.tv_sec - 10) {
+                                       logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+                                       send_req_key(from);
+                               }
+                               return true;
+                       }
+                       send_mtu_info(myself, from, MTU);
+               }
+
+               return true;
+       }
+
+       /* Requests that are not SPTPS data packets are forwarded as-is. */
+
+       if (to != myself)
+               return send_request(to->nexthop->connection, "%s", request);
+
+       /* The request is for us */
+
        switch(reqno) {
                case REQ_PUBKEY: {
                        if(!node_read_ecdsa_public_key(from)) {
@@ -176,24 +224,9 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, in
                        from->status.validkey = false;
                        from->status.waitingforkey = true;
                        from->last_req_key = now.tv_sec;
-                       sptps_start(&from->sptps, from, false, true, myself->connection->ecdsa, from->ecdsa, label, sizeof label, send_sptps_data, receive_sptps_record);
-                       sptps_receive_data(&from->sptps, buf, len);
-                       return true;
-               }
-
-               case REQ_SPTPS: {
-                       if(!from->status.validkey) {
-                               logger(DEBUG_PROTOCOL, LOG_ERR, "Got REQ_SPTPS from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
-                               return true;
-                       }
-
-                       char buf[MAX_STRING_SIZE];
-                       int len;
-                       if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1 || !(len = b64decode(buf, buf, strlen(buf)))) {
-                               logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_SPTPS", from->name, from->hostname, "invalid SPTPS data");
-                               return true;
-                       }
+                       sptps_start(&from->sptps, from, false, true, myself->connection->ecdsa, from->ecdsa, label, sizeof label, send_sptps_data_myself, receive_sptps_record);
                        sptps_receive_data(&from->sptps, buf, len);
+                       send_mtu_info(myself, from, MTU);
                        return true;
                }
 
@@ -241,7 +274,7 @@ bool req_key_h(connection_t *c, const char *request) {
        if(to == myself) {                      /* Yes */
                /* Is this an extended REQ_KEY message? */
                if(experimental && reqno)
-                       return req_key_ext_h(c, request, from, reqno);
+                       return req_key_ext_h(c, request, from, to, reqno);
 
                /* No, just send our key back */
                send_ans_key(from);
@@ -255,7 +288,10 @@ bool req_key_h(connection_t *c, const char *request) {
                        return true;
                }
 
-               /* TODO: forwarding SPTPS packets in this way is inefficient because we send them over TCP without checking for UDP connectivity */
+               /* Is this an extended REQ_KEY message? */
+               if(experimental && reqno)
+                       return req_key_ext_h(c, request, from, to, reqno);
+
                send_request(to->nexthop->connection, "%s", request);
        }
 
@@ -303,6 +339,8 @@ bool send_ans_key(node_t *to) {
        to->received = 0;
        if(replaywin) memset(to->late, 0, replaywin);
 
+       to->status.validkey_in = true;
+
        return send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
                                                myself->name, to->name, key,
                                                cipher_get_nid(to->incipher),
@@ -394,9 +432,18 @@ bool ans_key_h(connection_t *c, const char *request) {
        if(from->status.sptps) {
                char buf[strlen(key)];
                int len = b64decode(key, buf, strlen(key));
-
-               if(!len || !sptps_receive_data(&from->sptps, buf, len))
-                       logger(DEBUG_ALWAYS, LOG_ERR, "Error processing SPTPS data from %s (%s)", from->name, from->hostname);
+               if(!len || !sptps_receive_data(&from->sptps, buf, len)) {
+                       /* Uh-oh. It might be that the tunnel is stuck in some corrupted state,
+                          so let's restart SPTPS in case that helps. But don't do that too often
+                          to prevent storms.
+                          Note that simply relying on handshake timeout is not enough, because
+                          that doesn't apply to key regeneration. */
+                       if(from->last_req_key < now.tv_sec - 10) {
+                               logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode handshake TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+                               send_req_key(from);
+                       }
+                       return true;
+               }
 
                if(from->status.validkey) {
                        if(*address && *port) {
@@ -406,11 +453,13 @@ bool ans_key_h(connection_t *c, const char *request) {
                        }
                }
 
+               send_mtu_info(myself, from, MTU);
+
                return true;
        }
 
 #ifdef DISABLE_LEGACY
-       logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%) uses legacy protocol!", from->name, from->hostname);
+       logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses legacy protocol!", from->name, from->hostname);
        return false;
 #else
        /* Check and lookup cipher and digest algorithms */