#include <u.h>#include <libc.h>#include <authsrv.h> extern int form1M2B(char *ap, int n, uchar key[32]); intconvM2A(char *ap, int n, Authenticator *f, Ticket *t){	uchar buf[MAXAUTHENTLEN], *p;	int m; 	memset(f, 0, sizeof(Authenticator));	if(t->form == 0){		m = 1+CHALLEN+4;		if(n < m)			return -m;		memmove(buf, ap, m);		decrypt(t->key, buf, m);	} else {		m = 12+CHALLEN+NONCELEN+16;		if(n < m)			return -m;		memmove(buf, ap, m);		if(form1M2B((char*)buf, m, t->key) < 0)			return m;	}	p = buf;	f->num = *p++;	memmove(f->chal, p, CHALLEN);	p += CHALLEN;	if(t->form == 1)		memmove(f->rand, p, NONCELEN); 	return m;}