X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fprotocol_auth.c;h=65e96342f7f3504ab840f2b85080f9f8acb1aa97;hb=36623e15a1c8685e5d8730345c1a7f9c93710fef;hp=d38814c69d6d3bc40fcf927ab3c73f3801587822;hpb=8132be8fbd6c45be309c63a117f418ad12ced094;p=tinc

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index d38814c6..65e96342 100644
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -31,20 +31,30 @@
 #include "edge.h"
 #include "graph.h"
 #include "logger.h"
+#include "meta.h"
 #include "net.h"
 #include "netutl.h"
 #include "node.h"
 #include "prf.h"
 #include "protocol.h"
 #include "rsa.h"
+#include "sptps.h"
 #include "utils.h"
 #include "xalloc.h"
 
 bool send_id(connection_t *c) {
 	gettimeofday(&c->start, NULL);
 
-	return send_request(c, "%d %s %d.%d", ID, myself->connection->name,
-						myself->connection->protocol_major, myself->connection->protocol_minor);
+	int minor = 0;
+
+	if(experimental) {
+		if(c->config_tree && !read_ecdsa_public_key(c))
+			minor = 1;
+		else
+			minor = myself->connection->protocol_minor;
+	}
+
+	return send_request(c, "%d %s %d.%d", ID, myself->connection->name, myself->connection->protocol_major, minor);
 }
 
 bool id_h(connection_t *c, char *request) {
@@ -102,6 +112,9 @@ bool id_h(connection_t *c, char *request) {
 		return send_ack(c);
 	}
 
+	if(!experimental)
+		c->protocol_minor = 0;
+
 	if(!c->config_tree) {
 		init_configuration(&c->config_tree);
 
@@ -110,50 +123,34 @@ bool id_h(connection_t *c, char *request) {
 				   c->name);
 			return false;
 		}
+
+		if(experimental && c->protocol_minor >= 2) {
+			if(!read_ecdsa_public_key(c))
+				return false;
+		}
+	} else {
+		if(c->protocol_minor && !ecdsa_active(&c->ecdsa))
+			c->protocol_minor = 1;
 	}
 
 	c->allow_request = METAKEY;
 
-	if(c->protocol_minor >= 2)
-		return send_metakey_ec(c);
-	else
-		return send_metakey(c);
-}
-
-bool send_metakey_ec(connection_t *c) {
-	if(!read_ecdsa_public_key(c))
-		return false;
-
-	logger(LOG_DEBUG, "Sending ECDH metakey to %s", c->name);
-
-	size_t siglen = ecdsa_size(&myself->connection->ecdsa);
-
-	char key[ECDH_SIZE];
-	char sig[siglen];
-
-	// TODO: include nonce? Use relevant parts of SSH or TLS protocol
-
-	if(!ecdh_generate_public(&c->ecdh, key))
-		return false;
-
-	if(!ecdsa_sign(&myself->connection->ecdsa, key, ECDH_SIZE, sig))
-		return false;
+	if(c->protocol_minor >= 2) {
+		c->allow_request = ACK;
+		char label[25 + strlen(myself->name) + strlen(c->name)];
 
-	char out[MAX_STRING_SIZE];
+		if(c->outgoing)
+			snprintf(label, sizeof label, "tinc TCP key expansion %s %s", myself->name, c->name);
+		else
+			snprintf(label, sizeof label, "tinc TCP key expansion %s %s", c->name, myself->name);
 
-	bin2hex(key, out, ECDH_SIZE);
-	bin2hex(sig, out + ECDH_SIZE * 2, siglen);
-	out[(ECDH_SIZE + siglen) * 2] = 0;
-	
-	bool result = send_request(c, "%d %s", METAKEY, out);
+		return start_sptps(&c->sptps, c, c->outgoing, myself->connection->ecdsa, c->ecdsa, label, sizeof label, send_meta_sptps, receive_meta_sptps);
+	} else {
+		return send_metakey(c);
+	}
 }
 
 bool send_metakey(connection_t *c) {
-	size_t len = rsa_size(&c->rsa);
-	char key[len];
-	char enckey[len];
-	char hexkey[2 * len + 1];
-
 	if(!read_rsa_public_key(c))
 		return false;
 
@@ -163,6 +160,11 @@ bool send_metakey(connection_t *c) {
 	if(!digest_open_sha1(&c->outdigest, -1))
 		return false;
 
+	size_t len = rsa_size(&c->rsa);
+	char key[len];
+	char enckey[len];
+	char hexkey[2 * len + 1];
+
 	/* Create a random key */
 
 	randomize(key, len);
@@ -183,7 +185,6 @@ bool send_metakey(connection_t *c) {
 
 	ifdebug(SCARY_THINGS) {
 		bin2hex(key, hexkey, len);
-		hexkey[len * 2] = '\0';
 		logger(LOG_DEBUG, "Generated random meta key (unencrypted): %s", hexkey);
 	}
 
@@ -202,7 +203,6 @@ bool send_metakey(connection_t *c) {
 	/* Convert the encrypted random data to a hexadecimal formatted string */
 
 	bin2hex(enckey, hexkey, len);
-	hexkey[len * 2] = '\0';
 
 	/* Send the meta key */
 
@@ -215,91 +215,7 @@ bool send_metakey(connection_t *c) {
 	return result;
 }
 
-static bool metakey_ec_h(connection_t *c, const char *request) {
-	size_t siglen = ecdsa_size(&c->ecdsa);
-	char in[MAX_STRING_SIZE];
-	char key[MAX_STRING_SIZE];
-	char sig[siglen];
-
-	logger(LOG_DEBUG, "Got ECDH metakey from %s", c->name);
-
-	if(sscanf(request, "%*d " MAX_STRING, in) != 1) {
-		logger(LOG_ERR, "Got bad %s from %s (%s)", "METAKEY", c->name, c->hostname);
-		return false;
-	}
-
-	if(strlen(in) != (ECDH_SIZE + siglen) * 2) {
-		logger(LOG_ERR, "Possible intruder %s (%s): %s %d != %d", c->name, c->hostname, "wrong keylength", strlen(in) / 2, (ECDH_SIZE + siglen));
-		return false;
-	}
-
-	hex2bin(in, key, ECDH_SIZE);
-	hex2bin(in + ECDH_SIZE * 2, sig, siglen);
-
-	if(!ecdsa_verify(&c->ecdsa, key, ECDH_SIZE, sig)) {
-		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "invalid ECDSA signature");
-		return false;
-	}
-
-	char shared[ECDH_SHARED_SIZE * 2 + 1];
-
-	if(!ecdh_compute_shared(&c->ecdh, key, shared))
-		return false;
-
-	/* Update our crypto end */
-
-	if(!cipher_open_by_name(&c->incipher, "aes-256-ofb"))
-		return false;
-	if(!digest_open_by_name(&c->indigest, "sha512", -1))
-		return false;
-	if(!cipher_open_by_name(&c->outcipher, "aes-256-ofb"))
-		return false;
-	if(!digest_open_by_name(&c->outdigest, "sha512", -1))
-		return false;
-
-	size_t mykeylen = cipher_keylength(&c->incipher);
-	size_t hiskeylen = cipher_keylength(&c->outcipher);
-
-	char *mykey;
-	char *hiskey;
-	char *seed;
-	
-	if(strcmp(myself->name, c->name) < 0) {
-		mykey = key;
-		hiskey = key + mykeylen * 2;
-		xasprintf(&seed, "tinc TCP key expansion %s %s", myself->name, c->name);
-	} else {
-		mykey = key + hiskeylen * 2;
-		hiskey = key;
-		xasprintf(&seed, "tinc TCP key expansion %s %s", c->name, myself->name);
-	}
-
-	if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, hiskeylen * 2 + mykeylen * 2))
-		return false;
-
-	free(seed);
-
-	bin2hex(shared, shared, ECDH_SHARED_SIZE);
-	shared[ECDH_SHARED_SIZE * 2] = 0;
-	logger(LOG_DEBUG, "Shared secret is %s", shared);
-
-	cipher_set_key(&c->incipher, mykey, true);
-	digest_set_key(&c->indigest, mykey + mykeylen, mykeylen);
-
-	cipher_set_key(&c->outcipher, hiskey, false);
-	digest_set_key(&c->outdigest, hiskey + hiskeylen, hiskeylen);
-
-	c->status.decryptin = true;
-	c->status.encryptout = true;
-	c->allow_request = CHALLENGE;
-
-	return send_challenge(c);
-}
-
 bool metakey_h(connection_t *c, char *request) {
-	if(c->protocol_minor >= 2)
-		return metakey_ec_h(c, request);
-
 	char hexkey[MAX_STRING_SIZE];
 	int cipher, digest, maclength, compression;
 	size_t len = rsa_size(&myself->connection->rsa);
@@ -311,17 +227,17 @@ bool metakey_h(connection_t *c, char *request) {
 		return false;
 	}
 
+	/* Convert the challenge from hexadecimal back to binary */
+
+	int inlen = hex2bin(hexkey, enckey, sizeof enckey);
+
 	/* Check if the length of the meta key is all right */
 
-	if(strlen(hexkey) != len * 2) {
+	if(inlen != len) {
 		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong keylength");
 		return false;
 	}
 
-	/* Convert the challenge from hexadecimal back to binary */
-
-	hex2bin(hexkey, enckey, len);
-
 	/* Decrypt the meta key */
 
 	if(!rsa_private_decrypt(&myself->connection->rsa, enckey, len, key)) {
@@ -331,7 +247,6 @@ bool metakey_h(connection_t *c, char *request) {
 
 	ifdebug(SCARY_THINGS) {
 		bin2hex(key, hexkey, len);
-		hexkey[len * 2] = '\0';
 		logger(LOG_DEBUG, "Received random meta key (unencrypted): %s", hexkey);
 	}
 
@@ -355,7 +270,7 @@ bool metakey_h(connection_t *c, char *request) {
 }
 
 bool send_challenge(connection_t *c) {
-	size_t len = c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&c->rsa);
+	size_t len = rsa_size(&c->rsa);
 	char buffer[len * 2 + 1];
 
 	if(!c->hischallenge)
@@ -368,7 +283,6 @@ bool send_challenge(connection_t *c) {
 	/* Convert to hex */
 
 	bin2hex(c->hischallenge, buffer, len);
-	buffer[len * 2] = '\0';
 
 	/* Send the challenge */
 
@@ -377,7 +291,7 @@ bool send_challenge(connection_t *c) {
 
 bool challenge_h(connection_t *c, char *request) {
 	char buffer[MAX_STRING_SIZE];
-	size_t len = c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&myself->connection->rsa);
+	size_t len = rsa_size(&myself->connection->rsa);
 	size_t digestlen = digest_length(&c->indigest);
 	char digest[digestlen];
 
@@ -386,17 +300,17 @@ bool challenge_h(connection_t *c, char *request) {
 		return false;
 	}
 
+	/* Convert the challenge from hexadecimal back to binary */
+
+	int inlen = hex2bin(buffer, buffer, sizeof buffer);
+
 	/* Check if the length of the challenge is all right */
 
-	if(strlen(buffer) != len * 2) {
+	if(inlen != len) {
 		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge length");
 		return false;
 	}
 
-	/* Convert the challenge from hexadecimal back to binary */
-
-	hex2bin(buffer, buffer, len);
-
 	c->allow_request = CHAL_REPLY;
 
 	/* Calculate the hash from the challenge we received */
@@ -406,7 +320,6 @@ bool challenge_h(connection_t *c, char *request) {
 	/* Convert the hash to a hexadecimal formatted string */
 
 	bin2hex(digest, buffer, digestlen);
-	buffer[digestlen * 2] = '\0';
 
 	/* Send the reply */
 
@@ -422,20 +335,21 @@ bool chal_reply_h(connection_t *c, char *request) {
 		return false;
 	}
 
+	/* Convert the hash to binary format */
+
+	int inlen = hex2bin(hishash, hishash, sizeof hishash);
+
 	/* Check if the length of the hash is all right */
 
-	if(strlen(hishash) != digest_length(&c->outdigest) * 2) {
+	if(inlen != digest_length(&c->outdigest)) {
 		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply length");
 		return false;
 	}
 
-	/* Convert the hash to binary format */
-
-	hex2bin(hishash, hishash, digest_length(&c->outdigest));
 
 	/* Verify the hash */
 
-	if(!digest_verify(&c->outdigest, c->hischallenge, c->protocol_minor >= 2 ? ECDH_SIZE : rsa_size(&c->rsa), hishash)) {
+	if(!digest_verify(&c->outdigest, c->hischallenge, rsa_size(&c->rsa), hishash)) {
 		logger(LOG_ERR, "Possible intruder %s (%s): %s", c->name, c->hostname, "wrong challenge reply");
 		return false;
 	}
@@ -451,7 +365,24 @@ bool chal_reply_h(connection_t *c, char *request) {
 	return send_ack(c);
 }
 
+static bool send_upgrade(connection_t *c) {
+	/* Special case when protocol_minor is 1: the other end is ECDSA capable,
+	 * but doesn't know our key yet. So send it now. */
+
+	char *pubkey = ecdsa_get_base64_public_key(&myself->connection->ecdsa);
+
+	if(!pubkey)
+		return false;
+
+	bool result = send_request(c, "%d %s", ACK, pubkey);
+	free(pubkey);
+	return result;
+}
+
 bool send_ack(connection_t *c) {
+	if(c->protocol_minor == 1)
+		return send_upgrade(c);
+
 	/* ACK message contains rest of the information the other end needs
 	   to create node_t and edge_t structures. */
 
@@ -516,7 +447,29 @@ static void send_everything(connection_t *c) {
 	}
 }
 
+static bool upgrade_h(connection_t *c, char *request) {
+	char pubkey[MAX_STRING_SIZE];
+
+	if(sscanf(request, "%*d " MAX_STRING, pubkey) != 1) {
+		logger(LOG_ERR, "Got bad %s from %s (%s)", "ACK", c->name, c->hostname);
+		return false;
+	}
+
+	if(ecdsa_active(&c->ecdsa) || read_ecdsa_public_key(c)) {
+		logger(LOG_INFO, "Already have ECDSA public key from %s (%s), not upgrading.", c->name, c->hostname);
+		return false;
+	}
+
+	logger(LOG_INFO, "Got ECDSA public key from %s (%s), upgrading!", c->name, c->hostname);
+	append_config_file(c->name, "ECDSAPublicKey", pubkey);
+	c->allow_request = TERMREQ;
+	return send_termreq(c);
+}
+
 bool ack_h(connection_t *c, char *request) {
+	if(c->protocol_minor == 1)
+		return upgrade_h(c, request);
+
 	char hisport[MAX_STRING_SIZE];
 	char *hisaddress;
 	int weight, mtu;
@@ -613,7 +566,7 @@ bool ack_h(connection_t *c, char *request) {
 	if(tunnelserver)
 		send_add_edge(c, c->edge);
 	else
-		send_add_edge(broadcast, c->edge);
+		send_add_edge(everyone, c->edge);
 
 	/* Run MST and SSSP algorithms */