tcpsig_signature
if (tcpsig_signature(mp->b_cont, tcp, tcpha, tcplen, digest,
if (tcpsig_signature(mp1->b_cont, tcp, tcpha, tcplen, digest,
if (!tcpsig_signature(mp, tcp, tcpha,
extern bool tcpsig_signature(mblk_t *, tcp_t *, tcpha_t *, int, uint8_t *,