Fix compiler warnings.

[tinc] / src / protocol_key.c

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 8bbb6ad..dac1362 100644 (file)
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -84,7 +84,7 @@ bool key_changed_h(connection_t *c, char *request) {
 }
 
 bool send_req_key(node_t *to) {
-       return send_request(to->nexthop->connection, "%d %s %s 1", REQ_KEY, myself->name, to->name);
+       return send_request(to->nexthop->connection, "%d %s %s %d", REQ_KEY, myself->name, to->name, experimental ? 1 : 0);
 }
 
 bool req_key_h(connection_t *c, char *request) {
@@ -123,7 +123,7 @@ bool req_key_h(connection_t *c, char *request) {
        /* Check if this key request is for us */
 
        if(to == myself) {                      /* Yes, send our own key back */
-               if(kx_version > 0) {
+               if(experimental && kx_version >= 1) {
                        logger(LOG_DEBUG, "Got ECDH key request from %s", from->name);
                        from->status.ecdh = true;
                }
@@ -149,8 +149,7 @@ bool send_ans_key_ecdh(node_t *to) {
 
        ecdh_generate_public(&to->ecdh, key);
 
-       bin2hex(key, key, ECDH_SIZE);
-       key[ECDH_SIZE * 2] = '\0';
+       b64encode(key, key, ECDH_SIZE);
 
        return send_request(to->nexthop->connection, "%d %s %s ECDH:%s %d %d %zu %d", ANS_KEY,
                                                myself->name, to->name, key,
@@ -161,7 +160,7 @@ bool send_ans_key_ecdh(node_t *to) {
 }
 
 bool send_ans_key(node_t *to) {
-       if(to->status.ecdh)
+       if(experimental && to->status.ecdh)
                return send_ans_key_ecdh(to);
 
        size_t keylen = cipher_keylength(&myself->incipher);
@@ -176,7 +175,6 @@ bool send_ans_key(node_t *to) {
        digest_set_key(&to->indigest, key, keylen);
 
        bin2hex(key, key, keylen);
-       key[keylen * 2] = '\0';
 
        // Reset sequence number and late packet window
        mykeyused = true;
@@ -200,7 +198,7 @@ bool ans_key_h(connection_t *c, char *request) {
        int cipher, digest, maclength, compression, keylen;
        node_t *from, *to;
 
-       if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" %d %d %d %d "MAX_STRING" "MAX_STRING" %d",
+       if(sscanf(request, "%*d "MAX_STRING" "MAX_STRING" "MAX_STRING" %d %d %d %d "MAX_STRING" "MAX_STRING,
                from_name, to_name, key, &cipher, &digest, &maclength,
                &compression, address, port) < 7) {
                logger(LOG_ERR, "Got bad %s from %s (%s)", "ANS_KEY", c->name,
@@ -279,12 +277,9 @@ bool ans_key_h(connection_t *c, char *request) {
        from->outcompression = compression;
 
        /* ECDH or old-style key exchange? */
-       /* TODO: look at SSH and TLS to see how they derive cipher and HMAC keys from shared secret properly */
        
-       if(!strncmp(key, "ECDH:", 5)) {
-               logger(LOG_DEBUG, "Got ECDH key from %s", from->name);
-
-               keylen = (strlen(key) - 5) / 2;
+       if(experimental && !strncmp(key, "ECDH:", 5)) {
+               int keylen = b64decode(key + 5, key + 5, sizeof key - 5);
 
                if(keylen != ECDH_SIZE) {
                        logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
@@ -297,15 +292,12 @@ bool ans_key_h(connection_t *c, char *request) {
                }
 
                if(!from->ecdh) {
-                       logger(LOG_DEBUG, "Woops, we didn't generate our public key yet");
                        from->status.ecdh = true;
                        if(!send_ans_key(from))
                                return false;
                }
 
                char shared[ECDH_SHARED_SIZE * 2 + 1];
-               char hex[ECDH_SHARED_SIZE * 2 + 1];
-               hex2bin(key + 5, key + 5, keylen);
 
                if(!ecdh_compute_shared(&from->ecdh, key + 5, shared))
                        return false;
@@ -313,22 +305,23 @@ bool ans_key_h(connection_t *c, char *request) {
                /* Update our crypto end */
 
                size_t mykeylen = cipher_keylength(&myself->incipher);
-               keylen = cipher_keylength(&from->outcipher);
+               size_t hiskeylen = cipher_keylength(&from->outcipher);
 
                char *mykey;
-               char *seed = NULL;
+               char *hiskey;
+               char *seed;
                
                if(strcmp(myself->name, from->name) < 0) {
-                       logger(LOG_DEBUG, "Using left half of shared secret");
                        mykey = key;
-                       xasprintf(&seed, "tinc key expansion %s %s", myself->name, from->name);
+                       hiskey = key + mykeylen * 2;
+                       xasprintf(&seed, "tinc UDP key expansion %s %s", myself->name, from->name);
                } else {
-                       logger(LOG_DEBUG, "Using right half of shared secret");
-                       mykey = key + keylen;
-                       xasprintf(&seed, "tinc key expansion %s %s", from->name, myself->name);
+                       mykey = key + hiskeylen * 2;
+                       hiskey = key;
+                       xasprintf(&seed, "tinc UDP key expansion %s %s", from->name, myself->name);
                }
 
-               if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, keylen + mykeylen))
+               if(!prf(shared, ECDH_SHARED_SIZE, seed, strlen(seed), key, hiskeylen * 2 + mykeylen * 2))
                        return false;
 
                free(seed);
@@ -338,7 +331,10 @@ bool ans_key_h(connection_t *c, char *request) {
                from->incompression = myself->incompression;
 
                cipher_set_key(&from->incipher, mykey, true);
-               digest_set_key(&from->indigest, mykey, mykeylen);
+               digest_set_key(&from->indigest, mykey + mykeylen, mykeylen);
+
+               cipher_set_key(&from->outcipher, hiskey, false);
+               digest_set_key(&from->outdigest, hiskey + hiskeylen, hiskeylen);
 
                // Reset sequence number and late packet window
                mykeyused = true;
@@ -347,21 +343,20 @@ bool ans_key_h(connection_t *c, char *request) {
                        memset(from->late, 0, replaywin);
 
                if(strcmp(myself->name, from->name) < 0)
-                       memmove(key, key + mykeylen, keylen);
+                       memmove(key, key + mykeylen * 2, hiskeylen * 2);
        } else {
-               keylen = strlen(key) / 2;
-               hex2bin(key, key, keylen);
-       }
+               keylen = hex2bin(key, key, sizeof key);
 
-       /* Update our copy of the origin's packet key */
+               if(keylen != cipher_keylength(&from->outcipher)) {
+                       logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
+                       return false;
+               }
 
-       if(keylen != cipher_keylength(&from->outcipher)) {
-               logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name, from->hostname);
-               return false;
-       }
+               /* Update our copy of the origin's packet key */
 
-       cipher_set_key(&from->outcipher, key, false);
-       digest_set_key(&from->outdigest, key, keylen);
+               cipher_set_key(&from->outcipher, key, false);
+               digest_set_key(&from->outdigest, key, keylen);
+       }
 
        from->status.validkey = true;
        from->sent_seqno = 0;