Use AES256 and SHA256 by default, also for the meta-connections.

[tinc] / src / protocol_key.c

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 0ba5ad3..5f71d1c 100644 (file)
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -1,7 +1,7 @@
 /*
     protocol_key.c -- handle the meta-protocol, key exchange
     Copyright (C) 1999-2005 Ivo Timmermans,
-                  2000-2012 Guus Sliepen <guus@tinc-vpn.org>
+                  2000-2016 Guus Sliepen <guus@tinc-vpn.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -127,7 +127,8 @@ bool req_key_h(connection_t *c) {
        /* Check if this key request is for us */
 
        if(to == myself) {                      /* Yes, send our own key back */
-               send_ans_key(from);
+               if (!send_ans_key(from))
+                       return false;
        } else {
                if(tunnelserver)
                        return true;
@@ -156,9 +157,14 @@ bool send_ans_key(node_t *to) {
        to->inkey = xrealloc(to->inkey, to->inkeylength);
 
        // Create a new key
-       RAND_bytes((unsigned char *)to->inkey, to->inkeylength);
+       if (1 != RAND_bytes((unsigned char *)to->inkey, to->inkeylength)) {
+               int err = ERR_get_error();
+               logger(LOG_ERR, "Failed to generate random for key (%s)", ERR_error_string(err, NULL));
+               return false; // Do not send insecure keys, let connection attempt fail.
+       }
+
        if(to->incipher)
-               EVP_DecryptInit_ex(&to->inctx, to->incipher, NULL, (unsigned char *)to->inkey, (unsigned char *)to->inkey + to->incipher->key_len);
+               EVP_DecryptInit_ex(to->inctx, to->incipher, NULL, (unsigned char *)to->inkey, (unsigned char *)to->inkey + EVP_CIPHER_key_length(to->incipher));
 
        // Reset sequence number and late packet window
        mykeyused = true;
@@ -172,8 +178,8 @@ bool send_ans_key(node_t *to) {
 
        return send_request(to->nexthop->connection, "%d %s %s %s %d %d %d %d", ANS_KEY,
                        myself->name, to->name, key,
-                       to->incipher ? to->incipher->nid : 0,
-                       to->indigest ? to->indigest->type : 0, to->inmaclength,
+                       to->incipher ? EVP_CIPHER_nid(to->incipher) : 0,
+                       to->indigest ? EVP_MD_type(to->indigest) : 0, to->inmaclength,
                        to->incompression);
 }
 
@@ -227,7 +233,7 @@ bool ans_key_h(connection_t *c) {
                        return true;
                }
 
-               if(!*address && from->address.sa.sa_family != AF_UNSPEC) {
+               if(!*address && from->address.sa.sa_family != AF_UNSPEC && to->minmtu) {
                        char *address, *port;
                        ifdebug(PROTOCOL) logger(LOG_DEBUG, "Appending reflexive UDP address to ANS_KEY from %s to %s", from->name, to->name);
                        sockaddr2str(&from->address, &address, &port);
@@ -262,7 +268,7 @@ bool ans_key_h(connection_t *c) {
                        return true;
                }
 
-               if(from->outkeylength != from->outcipher->key_len + from->outcipher->iv_len) {
+               if(from->outkeylength != EVP_CIPHER_key_length(from->outcipher) + EVP_CIPHER_iv_length(from->outcipher)) {
                        logger(LOG_ERR, "Node %s (%s) uses wrong keylength!", from->name,
                                   from->hostname);
                        return true;
@@ -282,7 +288,7 @@ bool ans_key_h(connection_t *c) {
                        return true;
                }
 
-               if(from->outmaclength > from->outdigest->md_size || from->outmaclength < 0) {
+               if(from->outmaclength > EVP_MD_size(from->outdigest) || from->outmaclength < 0) {
                        logger(LOG_ERR, "Node %s (%s) uses bogus MAC length!",
                                   from->name, from->hostname);
                        return true;
@@ -299,7 +305,7 @@ bool ans_key_h(connection_t *c) {
        from->outcompression = compression;
 
        if(from->outcipher)
-               if(!EVP_EncryptInit_ex(&from->outctx, from->outcipher, NULL, (unsigned char *)from->outkey, (unsigned char *)from->outkey + from->outcipher->key_len)) {
+               if(!EVP_EncryptInit_ex(from->outctx, from->outcipher, NULL, (unsigned char *)from->outkey, (unsigned char *)from->outkey + EVP_CIPHER_key_length(from->outcipher))) {
                        logger(LOG_ERR, "Error during initialisation of key from %s (%s): %s",
                                        from->name, from->hostname, ERR_error_string(ERR_get_error(), NULL));
                        return true;