#include <u.h>#include <libc.h>#include <auth.h>#include "authlocal.h" static char *badreq = "bad ticket request";static char *ccmsg = "can't connect to AS";static char *srmsg = "server refused authentication";static char *sgmsg = "server gave up"; intauth(int fd){	int n, afd;	int rv;	char trbuf[TICKREQLEN];	char tbuf[2*TICKETLEN+AUTHENTLEN];	Ticketreq tr; 	/* add uid and local hostid to ticket request */	if(_asreadn(fd, trbuf, TICKREQLEN) < 0){		werrstr(badreq);		return -1;	}	convM2TR(trbuf, &tr);	if(tr.type != AuthTreq){		werrstr(badreq);		return -1;	}	memset(tr.uid, 0, sizeof(tr.uid));	strcpy(tr.uid, getuser());	memset(tr.hostid, 0, sizeof(tr.hostid));	_asrdfile("/dev/hostowner", tr.hostid, NAMELEN);	convTR2M(&tr, trbuf); 	/* get ticket */	afd = authdial();	if(afd < 0){		werrstr(ccmsg);		return -1;	}	rv = _asgetticket(afd, trbuf, tbuf);	close(afd);	if(rv)		return -1; 	/* get authenticator */	afd = open("/dev/authenticator", ORDWR);	if(afd < 0){		werrstr("/dev/authenticator: %r");		return -1;	}	if(write(afd, tbuf, TICKETLEN) < 0){		werrstr("writing /dev/authenticator: %r");		return -1;	}	if(read(afd, tbuf+2*TICKETLEN, AUTHENTLEN) < 0){		werrstr("reading /dev/authenticator: %r");		return -1;	} 	/* write server ticket to server */	if(write(fd, tbuf+TICKETLEN, TICKETLEN+AUTHENTLEN) < 0){		werrstr("%s:%r", srmsg);		return -1;	} 	/* get authenticator from server and check */	if(_asreadn(fd, tbuf+TICKETLEN, AUTHENTLEN) < 0){		werrstr(sgmsg);		return -1;	}	afd = open("/dev/authcheck", ORDWR);	if(afd < 0){		werrstr("authcheck: %r");		return -1;	}	n = write(afd, tbuf, TICKETLEN+AUTHENTLEN);	close(afd);	if(n < 0){		memset(tbuf, 0, AUTHENTLEN);		if(memcmp(tbuf, tbuf+TICKETLEN, AUTHENTLEN) == 0)			werrstr("refused by server");		else			werrstr("server lies");		return -1;	}	return 0;}