SSH2_MSG_KEX_DH_GEX_REPLY
ssh_dispatch_set(ssh, SSH2_MSG_KEX_DH_GEX_REPLY, &input_kex_dh_gex_reply);
ssh_dispatch_set(ssh, SSH2_MSG_KEX_DH_GEX_REPLY, &kex_protocol_error);
if ((r = sshpkt_start(ssh, SSH2_MSG_KEX_DH_GEX_REPLY)) != 0 ||