convm2t.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include <u.h>
#include <libc.h>
#include <authsrv.h>

#define	CHAR(x)		f->x = *p++
#define	SHORT(x)	f->x = (p[0] | (p[1]<<8)); p += 2
#define	VLONG(q)	q = (p[0] | (p[1]<<8) | (p[2]<<16) | (p[3]<<24)); p += 4
#define	LONG(x)		VLONG(f->x)
#define	STRING(x,n)	memmove(f->x, p, n); p += n

void
convM2T(char *ap, Ticket *f, char *key)
{
	uchar *p;

	if(key)
		decrypt(key, ap, TICKETLEN);
	p = (uchar*)ap;
	CHAR(num);
	STRING(chal, CHALLEN);
	STRING(cuid, ANAMELEN);
	f->cuid[ANAMELEN-1] = 0;
	STRING(suid, ANAMELEN);
	f->suid[ANAMELEN-1] = 0;
	STRING(key, DESKEYLEN);
	USED(p);
}