X-Git-Url: https://tinc-vpn.org/git/browse?p=tinc;a=blobdiff_plain;f=src%2Fprotocol_key.c;h=7e122068edd672c7a8117107675dab425bd6b59b;hp=39643cc34a589eca738ba005e1b0aa7ffa45d568;hb=ff306f0cdaedb50de1472e7c1fb55de922a6ca60;hpb=248d300f1be0d5f2aae39202041699ab2b46c56b

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 39643cc3..7e122068 100644
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -20,34 +20,43 @@
 
 #include "system.h"
 
-#include "splay_tree.h"
 #include "cipher.h"
 #include "connection.h"
 #include "crypto.h"
-#include "ecdh.h"
 #include "logger.h"
 #include "net.h"
 #include "netutl.h"
 #include "node.h"
 #include "prf.h"
 #include "protocol.h"
+#include "sptps.h"
 #include "utils.h"
 #include "xalloc.h"
 
 static bool mykeyused = false;
 
 void send_key_changed(void) {
-	splay_node_t *node;
-	connection_t *c;
-
 	send_request(everyone, "%d %x %s", KEY_CHANGED, rand(), myself->name);
 
 	/* Immediately send new keys to directly connected nodes to keep UDP mappings alive */
 
-	for(node = connection_tree->head; node; node = node->next) {
-		c = node->data;
-		if(c->status.active && c->node && c->node->status.reachable)
-			send_ans_key(c->node);
+	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->node && c->node->status.reachable) {
+			if(!c->node->status.sptps)
+				send_ans_key(c->node);
+		}
+	}
+
+	/* Force key exchange for connections using SPTPS */
+
+	if(experimental) {
+		for(splay_node_t *node = node_tree->head; node; node = node->next) {
+			node_t *n = node->data;
+			if(n->status.reachable && n->status.validkey && n->status.sptps)
+				sptps_force_kex(&n->sptps);
+		}
 	}
 }
 
@@ -72,8 +81,10 @@ bool key_changed_h(connection_t *c, const char *request) {
 		return true;
 	}
 
-	n->status.validkey = false;
-	n->last_req_key = 0;
+	if(!n->status.sptps) {
+		n->status.validkey = false;
+		n->last_req_key = 0;
+	}
 
 	/* Tell the others */
 
@@ -83,11 +94,31 @@ bool key_changed_h(connection_t *c, const char *request) {
 	return true;
 }
 
+static bool send_initial_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
+	node_t *to = handle;
+	to->sptps.send_data = send_sptps_data;
+	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);
+}
+
 bool send_req_key(node_t *to) {
-	if(experimental && OPTION_VERSION(to->options) >= 2) {
-		if(!node_read_ecdsa_public_key(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);
 			send_request(to->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, to->name, REQ_PUBKEY);
+			return true;
+		}
+                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);
+		to->status.validkey = false;
+		to->status.waitingforkey = true;
+		to->last_req_key = time(NULL);
+		to->incompression = myself->incompression;
+		return sptps_start(&to->sptps, to, true, true, myself->connection->ecdsa, to->ecdsa, label, sizeof label, send_initial_sptps_data, receive_sptps_record); 
 	}
+
 	return send_request(to->nexthop->connection, "%d %s %s", REQ_KEY, myself->name, to->name);
 }
 
@@ -104,21 +135,65 @@ static bool req_key_ext_h(connection_t *c, const char *request, node_t *from, in
 
 		case ANS_PUBKEY: {
 			if(node_read_ecdsa_public_key(from)) {
-				logger(DEBUG_ALWAYS, LOG_WARNING, "Got ANS_PUBKEY from %s (%s) even though we already have his pubkey", from->name, from->hostname);
+				logger(DEBUG_PROTOCOL, LOG_WARNING, "Got ANS_PUBKEY from %s (%s) even though we already have his pubkey", from->name, from->hostname);
 				return true;
 			}
 
-			char pubkey[4096];
+			char pubkey[MAX_STRING_SIZE];
 			if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, pubkey) != 1 || !ecdsa_set_base64_public_key(&from->ecdsa, pubkey)) {
 				logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "ANS_PUBKEY", from->name, from->hostname, "invalid pubkey");
 				return true;
 			}
 
-			logger(DEBUG_ALWAYS, LOG_INFO, "Learned ECDSA public key from %s (%s)", from->name, from->hostname);
+			logger(DEBUG_PROTOCOL, LOG_INFO, "Learned ECDSA public key from %s (%s)", from->name, from->hostname);
 			append_config_file(from->name, "ECDSAPublicKey", 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);
+				send_request(from->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, from->name, REQ_PUBKEY);
+				return true;
+			}
+		}
+
+		case REQ_SPTPS: {
+			char buf[MAX_STRING_SIZE];
+			if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1) {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_KEY", 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);
+			sptps_stop(&from->sptps);
+			from->status.validkey = false;
+			from->status.waitingforkey = true;
+			from->last_req_key = time(NULL);
+			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_PACKET: {
+			if(!from->status.validkey) {
+				logger(DEBUG_PROTOCOL, LOG_ERR, "Got REQ_PACKET from %s (%s) but we don't have a valid key yet", from->name, from->hostname);
+				return true;
+			}
+
+			char buf[MAX_STRING_SIZE];
+			if(sscanf(request, "%*d %*s %*s %*d " MAX_STRING, buf) != 1) {
+				logger(DEBUG_ALWAYS, LOG_ERR, "Got bad %s from %s (%s): %s", "REQ_KEY", 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;
+		}
+
 		default:
 			logger(DEBUG_ALWAYS, LOG_ERR, "Unknown extended REQ_KEY request from %s (%s): %s", from->name, from->hostname, request);
 			return true;
@@ -160,17 +235,19 @@ bool req_key_h(connection_t *c, const char *request) {
 
 	/* Check if this key request is for us */
 
-	if(to == myself) {			/* Yes, send our own key back */
+	if(to == myself) {			/* Yes */
+		/* Is this an extended REQ_KEY message? */
 		if(experimental && reqno)
 			return req_key_ext_h(c, request, from, reqno);
 
+		/* No, just send our key back */
 		send_ans_key(from);
 	} else {
 		if(tunnelserver)
 			return true;
 
 		if(!to->status.reachable) {
-			logger(DEBUG_ALWAYS, LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
+			logger(DEBUG_PROTOCOL, LOG_WARNING, "Got %s from %s (%s) destination %s which is not reachable",
 				"REQ_KEY", c->name, c->hostname, to_name);
 			return true;
 		}
@@ -181,31 +258,9 @@ bool req_key_h(connection_t *c, const char *request) {
 	return true;
 }
 
-bool send_ans_key_ecdh(node_t *to) {
-	int siglen = ecdsa_size(&myself->connection->ecdsa);
-	char key[(ECDH_SIZE + siglen) * 2 + 1];
-
-	if(!ecdh_generate_public(&to->ecdh, key))
-		return false;
-
-	if(!ecdsa_sign(&myself->connection->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE))
-		return false;
-
-	b64encode(key, key, ECDH_SIZE + siglen);
-
-	int result = send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
-						myself->name, to->name, key,
-						cipher_get_nid(&myself->incipher),
-						digest_get_nid(&myself->indigest),
-						(int)digest_length(&myself->indigest),
-						myself->incompression);
-
-	return result;
-}
-
 bool send_ans_key(node_t *to) {
-	if(experimental && OPTION_VERSION(to->options) >= 2)
-		return send_ans_key_ecdh(to);
+	if(to->status.sptps)
+		abort();
 
 	size_t keylen = cipher_keylength(&myself->incipher);
 	char key[keylen * 2 + 1];
@@ -296,22 +351,8 @@ bool ans_key_h(connection_t *c, const char *request) {
 		return send_request(to->nexthop->connection, "%s", request);
 	}
 
-	/* Check and lookup cipher and digest algorithms */
-
-	if(!cipher_open_by_nid(&from->outcipher, cipher)) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
-		return false;
-	}
-
-	if(!digest_open_by_nid(&from->outdigest, digest, maclength)) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
-		return false;
-	}
-
-	if(maclength != digest_length(&from->outdigest)) {
-		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus MAC length!", from->name, from->hostname);
-		return false;
-	}
+	/* Don't use key material until every check has passed. */
+	from->status.validkey = false;
 
 	if(compression < 0 || compression > 11) {
 		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus compression level!", from->name, from->hostname);
@@ -320,99 +361,59 @@ bool ans_key_h(connection_t *c, const char *request) {
 
 	from->outcompression = compression;
 
-	/* ECDH or old-style key exchange? */
-	
-	if(experimental && OPTION_VERSION(from->options) >= 2) {
-		/* Check if we already have an ECDSA public key for this node. */
-
-		if(!node_read_ecdsa_public_key(from)) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "No ECDSA public key known for %s (%s), cannot verify ECDH key exchange!", from->name, from->hostname);
-			return true;
-		}
-
-		int siglen = ecdsa_size(&from->ecdsa);
-		int keylen = b64decode(key, key, sizeof key);
-
-		if(keylen != ECDH_SIZE + siglen) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength! %d != %d", from->name, from->hostname, keylen, ECDH_SIZE + siglen);
-			return true;
-		}
-
-		if(ECDH_SHARED_SIZE < cipher_keylength(&from->outcipher)) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "ECDH key too short for cipher of %s!", from->name);
-			return true;
-		}
-
-		if(!ecdsa_verify(&from->ecdsa, key, ECDH_SIZE, key + ECDH_SIZE)) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "Possible intruder %s (%s): %s", from->name, from->hostname, "invalid ECDSA signature");
-			return true;
-		}
+	/* SPTPS or old-style key exchange? */
 
-		if(!from->ecdh) {
-			if(!send_ans_key_ecdh(from))
-				return true;
-		}
+	if(from->status.sptps) {
+		char buf[strlen(key)];
+		int len = b64decode(key, buf, strlen(key));
 
-		char shared[ECDH_SHARED_SIZE * 2 + 1];
+		if(!sptps_receive_data(&from->sptps, buf, len))
+			logger(DEBUG_ALWAYS, LOG_ERR, "Error processing SPTPS data from %s (%s)", from->name, from->hostname);
 
-		if(!ecdh_compute_shared(&from->ecdh, key, shared))
-			return true;
+		if(from->status.validkey) {
+			if(*address && *port) {
+				logger(DEBUG_PROTOCOL, LOG_DEBUG, "Using reflexive UDP address from %s: %s port %s", from->name, address, port);
+				sockaddr_t sa = str2sockaddr(address, port);
+				update_node_udp(from, &sa);
+			}
 
-		/* Update our crypto end */
-
-		size_t mykeylen = cipher_keylength(&myself->incipher);
-		size_t hiskeylen = cipher_keylength(&from->outcipher);
-
-		char *mykey;
-		char *hiskey;
-		char *seed;
-		
-		if(strcmp(myself->name, from->name) < 0) {
-			mykey = key;
-			hiskey = key + mykeylen * 2;
-			xasprintf(&seed, "tinc UDP key expansion %s %s", myself->name, from->name);
-		} else {
-			mykey = key + hiskeylen * 2;
-			hiskey = key;
-			xasprintf(&seed, "tinc UDP key expansion %s %s", from->name, myself->name);
+			if(from->options & OPTION_PMTU_DISCOVERY)
+				send_mtu_probe(from);
 		}
 
-		if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, hiskeylen * 2 + mykeylen * 2))
-			return true;
+		return true;
+	}
 
-		free(seed);
+	/* Check and lookup cipher and digest algorithms */
 
-		cipher_open_by_nid(&from->incipher, cipher_get_nid(&myself->incipher));
-		digest_open_by_nid(&from->indigest, digest_get_nid(&myself->indigest), digest_length(&myself->indigest));
-		from->incompression = myself->incompression;
+	if(!cipher_open_by_nid(&from->outcipher, cipher)) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown cipher!", from->name, from->hostname);
+		return false;
+	}
 
-		cipher_set_key(&from->incipher, mykey, false);
-		digest_set_key(&from->indigest, mykey + mykeylen, mykeylen);
+	if(!digest_open_by_nid(&from->outdigest, digest, maclength)) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses unknown digest!", from->name, from->hostname);
+		return false;
+	}
 
-		cipher_set_key(&from->outcipher, hiskey, true);
-		digest_set_key(&from->outdigest, hiskey + hiskeylen, hiskeylen);
+	if(maclength != digest_length(&from->outdigest)) {
+		logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses bogus MAC length!", from->name, from->hostname);
+		return false;
+	}
 
-		// Reset sequence number and late packet window
-		mykeyused = true;
-		from->received_seqno = 0;
-		if(replaywin)
-			memset(from->late, 0, replaywin);
+	/* Process key */
 
-		if(strcmp(myself->name, from->name) < 0)
-			memmove(key, key + mykeylen * 2, hiskeylen * 2);
-	} else {
-		keylen = hex2bin(key, key, sizeof key);
+	keylen = hex2bin(key, key, sizeof key);
 
-		if(keylen != cipher_keylength(&from->outcipher)) {
-			logger(DEBUG_ALWAYS, LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
-			return true;
-		}
+	if(keylen != cipher_keylength(&from->outcipher)) {
+		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 */
+	/* Update our copy of the origin's packet key */
 
-		cipher_set_key(&from->outcipher, key, true);
-		digest_set_key(&from->outdigest, key, keylen);
-	}
+	cipher_set_key(&from->outcipher, key, true);
+	digest_set_key(&from->outdigest, key, keylen);
 
 	from->status.validkey = true;
 	from->sent_seqno = 0;