Add strict checks to hex to binary conversions.

[tinc] / src / protocol_key.c

diff --git a/src/protocol_key.c b/src/protocol_key.c
index 1a184fb..f2f317d 100644 (file)
--- a/src/protocol_key.c
+++ b/src/protocol_key.c
@@ -240,10 +240,16 @@ bool ans_key_h(connection_t *c) {
                return send_request(to->nexthop->connection, "%s", c->buffer);
        }
 
+       /* Don't use key material until every check has passed. */
+       from->status.validkey = false;
+
        /* Update our copy of the origin's packet key */
        from->outkey = xrealloc(from->outkey, strlen(key) / 2);
        from->outkeylength = strlen(key) / 2;
-       hex2bin(key, from->outkey, from->outkeylength);
+       if(!hex2bin(key, from->outkey, from->outkeylength)) {
+               logger(LOG_ERR, "Got bad %s from %s(%s): %s", "ANS_KEY", from->name, from->hostname, "invalid key");
+               return true;
+       }
 
        /* Check and lookup cipher and digest algorithms */