X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fprotocol_key.c;h=ebc46f32ae3bf57559ecb0d90938d7e8390e66f8;hb=63daebcd1ec2975c0c2ad8e0ee0fced33b1fbbf0;hp=7f6e1653e4e7c71436fda21567d6ab33f2ca1663;hpb=9b9230a0a79c670b86f54fadd2807b864ff9d91f;p=tinc

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 7f6e1653..ebc46f32 100644
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -41,7 +41,7 @@ void send_key_changed(void) {
 	/* Immediately send new keys to directly connected nodes to keep UDP mappings alive */
 
 	for list_each(connection_t, c, connection_list)
-		if(c->status.active && c->node && c->node->status.reachable && !c->node->status.sptps)
+		if(c->edge && c->node && c->node->status.reachable && !c->node->status.sptps)
 			send_ans_key(c->node);
 
 	/* Force key exchange for connections using SPTPS */
@@ -98,7 +98,7 @@ static bool send_initial_sptps_data(void *handle, uint8_t type, const char *data
 bool send_req_key(node_t *to) {
 	if(to->status.sptps) {
 		if(!node_read_ecdsa_public_key(to)) {
-			logger(DEBUG_PROTOCOL, LOG_DEBUG, "No ECDSA key known for %s (%s)", to->name, to->hostname);
+			logger(DEBUG_PROTOCOL, LOG_DEBUG, "No Ed25519 key known for %s (%s)", to->name, to->hostname);
 			send_request(to->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, to->name, REQ_PUBKEY);
 			return true;
 		}
@@ -124,6 +124,11 @@ bool send_req_key(node_t *to) {
 static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, int reqno) {
 	switch(reqno) {
 		case REQ_PUBKEY: {
+			if(!node_read_ecdsa_public_key(from)) {
+				/* Request their key *before* we send our key back. Otherwise the first SPTPS packet from them will get dropped. */
+				logger(DEBUG_PROTOCOL, LOG_DEBUG, "Preemptively requesting Ed25519 key for %s (%s)", from->name, from->hostname);
+				send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
+			}
 			char *pubkey = ecdsa_get_base64_public_key(myself->connection->ecdsa);
 			send_request(from->nexthop->connection, "%d %s %s %d %s", REQ_KEY, myself->name, from->name, ANS_PUBKEY, pubkey);
 			free(pubkey);
@@ -142,14 +147,14 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, in
 				return true;
 			}
 
-			logger(DEBUG_PROTOCOL, LOG_INFO, "Learned ECDSA public key from %s (%s)", from->name, from->hostname);
-			append_config_file(from->name, "ECDSAPublicKey", pubkey);
+			logger(DEBUG_PROTOCOL, LOG_INFO, "Learned Ed25519 public key from %s (%s)", from->name, from->hostname);
+			append_config_file(from->name, "Ed25519PublicKey", pubkey);
 			return true;
 		}
 
 		case REQ_KEY: {
 			if(!node_read_ecdsa_public_key(from)) {
-				logger(DEBUG_PROTOCOL, LOG_DEBUG, "No ECDSA key known for %s (%s)", from->name, from->hostname);
+				logger(DEBUG_PROTOCOL, LOG_DEBUG, "No Ed25519 key known for %s (%s)", from->name, from->hostname);
 				send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
 				return true;
 			}
@@ -158,11 +163,12 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, in
 				logger(DEBUG_ALWAYS, LOG_DEBUG, "Got REQ_KEY from %s while we already started a SPTPS session!", from->name);
 
 			char buf[MAX_STRING_SIZE];
-			if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1) {
+			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_START", from->name, from->hostname, "invalid SPTPS data");
 				return true;
 			}
-			int len = b64decode(buf, buf, strlen(buf));
 
 			char label[25 + strlen(from->name) + strlen(myself->name)];
 			snprintf(label, sizeof label, "tinc UDP key expansion %s %s", from->name, myself->name);
@@ -182,11 +188,11 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, in
 			}
 
 			char buf[MAX_STRING_SIZE];
-			if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1) {
+			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;
 			}
-			int len = b64decode(buf, buf, strlen(buf));
 			sptps_receive_data(&from->sptps, buf, len);
 			return true;
 		}
@@ -249,6 +255,7 @@ 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 */
 		send_request(to->nexthop->connection, "%s", request);
 	}
 
@@ -259,22 +266,31 @@ bool send_ans_key(node_t *to) {
 	if(to->status.sptps)
 		abort();
 
-	size_t keylen = cipher_keylength(myself->incipher);
+	size_t keylen = myself->incipher ? cipher_keylength(myself->incipher) : 1;
 	char key[keylen * 2 + 1];
 
+	randomize(key, keylen);
+
 	cipher_close(to->incipher);
 	digest_close(to->indigest);
 
-	to->incipher = cipher_open_by_nid(cipher_get_nid(myself->incipher));
-	to->indigest = digest_open_by_nid(digest_get_nid(myself->indigest), digest_length(myself->indigest));
-	to->incompression = myself->incompression;
+	if(myself->incipher) {
+		to->incipher = cipher_open_by_nid(cipher_get_nid(myself->incipher));
+		if(!to->incipher)
+			abort();
+		if(!cipher_set_key(to->incipher, key, false))
+			abort();
+	}
 
-	if(!to->incipher || !to->indigest)
-		abort();
+	if(myself->indigest) {
+		to->indigest = digest_open_by_nid(digest_get_nid(myself->indigest), digest_length(myself->indigest));
+		if(!to->indigest)
+			abort();
+		if(!digest_set_key(to->indigest, key, keylen))
+			abort();
+	}
 
-	randomize(key, keylen);
-	cipher_set_key(to->incipher, key, false);
-	digest_set_key(to->indigest, key, keylen);
+	to->incompression = myself->incompression;
 
 	bin2hex(key, key, keylen);
 
@@ -373,7 +389,7 @@ bool ans_key_h(connection_t *c, const char *request) {
 		char buf[strlen(key)];
 		int len = b64decode(key, buf, strlen(key));
 
-		if(!sptps_receive_data(&from->sptps, buf, len))
+		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(from->status.validkey) {
@@ -383,7 +399,9 @@ bool ans_key_h(connection_t *c, const char *request) {
 				update_node_udp(from, &sa);
 			}
 
-			if(from->options & OPTION_PMTU_DISCOVERY)
+			/* Don't send probes if we can't send UDP packets directly to that node.
+			   TODO: the indirect (via) condition can change at any time as edges are added and removed, so this should probably be moved to graph.c. */
+			if((from->via == myself || from->via == from) && from->options & OPTION_PMTU_DISCOVERY && !(from->options & OPTION_TCPONLY))
 				send_mtu_probe(from);
 		}
 
@@ -392,14 +410,22 @@ bool ans_key_h(connection_t *c, const char *request) {
 
 	/* Check and lookup cipher and digest algorithms */
 
-	if(!(from->outcipher = cipher_open_by_nid(cipher))) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
-		return false;
+	if(cipher) {
+		if(!(from->outcipher = cipher_open_by_nid(cipher))) {
+			logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
+			return false;
+		}
+	} else {
+		from->outcipher = NULL;
 	}
 
-	if(!(from->outdigest = digest_open_by_nid(digest, maclength))) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
-		return false;
+	if(digest) {
+		if(!(from->outdigest = digest_open_by_nid(digest, maclength))) {
+			logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
+			return false;
+		}
+	} else {
+		from->outdigest = NULL;
 	}
 
 	if(maclength != digest_length(from->outdigest)) {
@@ -411,15 +437,17 @@ bool ans_key_h(connection_t *c, const char *request) {
 
 	keylen = hex2bin(key, key, sizeof key);
 
-	if(keylen != cipher_keylength(from->outcipher)) {
+	if(keylen != (from->outcipher ? cipher_keylength(from->outcipher) : 1)) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
 		return true;
 	}
 
 	/* Update our copy of the origin's packet key */
 
-	cipher_set_key(from->outcipher, key, true);
-	digest_set_key(from->outdigest, key, keylen);
+	if(from->outcipher && !cipher_set_key(from->outcipher, key, true))
+		return false;
+	if(from->outdigest && !digest_set_key(from->outdigest, key, keylen))
+		return false;
 
 	from->status.validkey = true;
 	from->sent_seqno = 0;
@@ -430,7 +458,7 @@ bool ans_key_h(connection_t *c, const char *request) {
 		update_node_udp(from, &sa);
 	}
 
-	if(from->options & OPTION_PMTU_DISCOVERY)
+	if(from->options & OPTION_PMTU_DISCOVERY && !(from->options & OPTION_TCPONLY))
 		send_mtu_probe(from);
 
 	return true;