Merge remote-tracking branches 'dechamps/sptpsrestart' and 'dechamps/keychanged'...

diff --git a/src/net_packet.c b/src/net_packet.c
index 92a3eb5..8313a54 100644 (file)
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -288,7 +288,14 @@ static bool receive_udppacket(node_t *n, vpn_packet_t *inpkt) {
                n->status.udppacket = false;
 
                if(!result) {
-                       logger(DEBUG_TRAFFIC, LOG_ERR, "Got bad packet from %s (%s)", n->name, n->hostname);
+                       /* 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, and because that would make life a little too easy
+                          for external attackers trying to DoS us. */
+                       if(n->last_req_key < now.tv_sec - 10) {
+                               logger(DEBUG_PROTOCOL, LOG_ERR, "Failed to decode raw TCP packet from %s (%s), restarting SPTPS", n->name, n->hostname);
+                               send_req_key(n);
+                       }
                        return false;
                }
                return true;
@@ -464,11 +471,17 @@ bool receive_tcppacket_sptps(connection_t *c, const char *data, int len) {
 
        /* The packet is for us */
 
-       if(!from->status.validkey) {
-               logger(DEBUG_PROTOCOL, LOG_ERR, "Got SPTPS packet from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
+       if(!sptps_receive_data(&from->sptps, data, 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 raw TCP packet from %s (%s), restarting SPTPS", from->name, from->hostname);
+                       send_req_key(from);
+               }
                return true;
        }
-       sptps_receive_data(&from->sptps, data, len);
+
        send_mtu_info(myself, from, MTU);
        return true;
 }

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 6721aa4..b409a35 100644 (file)
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -109,9 +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);
@@ -150,11 +147,16 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, no
                        try_tx(to, true);
                } else {
                        /* The packet is for us */
-                       if(!from->status.validkey) {
-                               logger(DEBUG_PROTOCOL, LOG_ERR, "Got SPTPS_PACKET from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
+                       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;
                        }
-                       sptps_receive_data(&from->sptps, buf, len);
                        send_mtu_info(myself, from, MTU);
                }
 
@@ -430,9 +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) {

diff --git a/src/sptps.c b/src/sptps.c
index e5946ed..d6e6d41 100644 (file)
--- a/src/sptps.c
+++ b/src/sptps.c
@@ -447,6 +447,7 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
        uint32_t seqno;
        memcpy(&seqno, data, 4);
        seqno = ntohl(seqno);
+       data += 4; len -= 4;
 
        if(!s->instate) {
                if(seqno != s->inseqno)
@@ -454,38 +455,39 @@ static bool sptps_receive_data_datagram(sptps_t *s, const char *data, size_t len
 
                s->inseqno = seqno + 1;
 
-               uint8_t type = data[4];
+               uint8_t type = *(data++); len--;
 
                if(type != SPTPS_HANDSHAKE)
                        return error(s, EIO, "Application record received before handshake finished");
 
-               return receive_handshake(s, data + 5, len - 5);
+               return receive_handshake(s, data, len);
        }
 
        // Decrypt
 
        char buffer[len];
-
        size_t outlen;
-
-       if(!chacha_poly1305_decrypt(s->incipher, seqno, data + 4, len - 4, buffer, &outlen))
+       if(!chacha_poly1305_decrypt(s->incipher, seqno, data, len, buffer, &outlen))
                return error(s, EIO, "Failed to decrypt and verify packet");
 
        if(!sptps_check_seqno(s, seqno, true))
                return false;
 
        // Append a NULL byte for safety.
-       buffer[len - 20] = 0;
+       buffer[outlen] = 0;
+
+       data = buffer;
+       len = outlen;
 
-       uint8_t type = buffer[0];
+       uint8_t type = *(data++); len--;
 
        if(type < SPTPS_HANDSHAKE) {
                if(!s->instate)
                        return error(s, EIO, "Application record received before handshake finished");
-               if(!s->receive_record(s->handle, type, buffer + 1, len - 21))
+               if(!s->receive_record(s->handle, type, data, len))
                        return false;
        } else if(type == SPTPS_HANDSHAKE) {
-               if(!receive_handshake(s, buffer + 1, len - 21))
+               if(!receive_handshake(s, data, len))
                        return false;
        } else {
                return error(s, EIO, "Invalid record type %d", type);