LDP_HDR_PDU_LEN
size = LDP_HDR_PDU_LEN;
if ((pdu_len < (LDP_HDR_PDU_LEN + LDP_MSG_SIZE)) ||
if (pdu_len < (LDP_HDR_PDU_LEN + LDP_MSG_SIZE) ||
pdu_len -= LDP_HDR_PDU_LEN;