silently ignore additional keytag options

(cherry picked from commit 36158e6c96e982768bd33d4090cbe563718534f2)

diff --git a/lib/ns/client.c b/lib/ns/client.c
index 5dae36ad70cecbce58bd9ac5b57ffc8b0ddb9f82..bc1cf7395a8f1ec294f3fd9f1f6e321e5fbf98f0 100644 (file)
--- a/lib/ns/client.c
+++ b/lib/ns/client.c
@@ -2120,6 +2120,12 @@ process_keytag(ns_client_t *client, isc_buffer_t *buf, size_t optlen) {
                return (DNS_R_OPTERR);
        }
 
+       /* Silently drop additional keytag options. */
+       if (client->keytag != NULL) {
+               isc_buffer_forward(buf, (unsigned int)optlen);
+               return (ISC_R_SUCCESS);
+       }
+
        client->keytag = isc_mem_get(client->mctx, optlen);
        if (client->keytag != NULL) {
                client->keytag_len = (uint16_t)optlen;