sec_svc_getcred
if (sec_svc_getcred(req, cr, &cs->principal, &cs->nfsflavor) == 0) {
stat = sec_svc_getcred(req, cr, &principal, &nfsflavor);
extern int sec_svc_getcred(struct svc_req *, cred_t *, caddr_t *, int *);