Check RAND_bytes() return value, fail when getting random fails.

[tinc] / src / protocol_key.c

diff --git a/src/protocol_key.c b/src/protocol_key.c
index f2f317d..b55e830 100644 (file)
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -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;
@@ -156,7 +157,12 @@ bool send_ans_key(node_t *to) {
        to->inkey = xrealloc(to->inkey, to->inkeylength);
 
        // Create a new key
-       RAND_pseudo_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)", "SEND_ANS_KEY", 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);