main.c

早期freebsd实现

/*-
 * Copyright (c) 1993 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Bill Jolitz.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1993 The Regents of the University of California.\n\
 All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)main.c	5.2 (Berkeley) 5/29/93";
#endif /* not lint */

#include "main.h"
#include <sys/time.h>
#include <sys/ioctl.h>

#include <signal.h>
#include <sys/types.h>
#include <utmp.h>
#include <setjmp.h>
#include <sys/reboot.h>
#include <errno.h>
#include <sys/file.h>
#include <ttyent.h>
#include <sys/syslog.h>
#include <sys/stat.h>

#define	LINSIZ	sizeof(wtmp.ut_line)
#define	CMDSIZ	200	/* max string length for getty or window command*/
#define	ALL	p = itab; p ; p = p->next
#define	EVER	;;
#define SCPYN(a, b)	strncpy(a, b, sizeof(a))
#define SCMPN(a, b)	strncmp(a, b, sizeof(a))

char	shell[]	= "/bin/sh";
char	minus[]	= "-";
char	runc[]	= "/etc/rc";
char	utmpf[]	= "/etc/utmp";
char	wtmpf[]	= "/usr/adm/wtmp";
char	ctty[]	= "/dev/console";


struct utmp wtmp;
struct	tab
{
	char	line[LINSIZ];
	char	comn[CMDSIZ];
	int		baud;		/* outgoing baud rate */
	int		sock;		/* socket if outgoing connected */
	int		fd;		/* file desc if we have, else -1 */
	int		errfd;		/* error file desc if we have, else -1 */
	char	xflag;
	int		gpid;		/* pid of getty or connector */
	time_t	gettytime;
	int	gettycnt;
	struct	tab *next;
} *itab;

char	tty3[LINSIZ] = { "tty3" } ;
char	tty2[LINSIZ] = { "tty2" } ;
int	fi;
int	mergflag;
char	tty[20];
jmp_buf	sjbuf, shutpass;
time_t	time0;

int	reset();
int	idle();
char	*strcpy(), *strcat();
long	lseek();

struct conversation  convers[MAXCONNECTS] ;
jmp_buf terminate;

fd_set rd_fdset, wr_fdset ;
int term(), sigpipe();
int debug;
extern int errno;
struct timeval tv_2th = { 0, 500000 } ;
main (argc,argv) char *argv[]; {
	int sock, msgsock, rval, rv ;
	struct sockaddr_un rqsts;
	int err;
	struct iovec iov[4];
	int constatus, rqst, resp;
	int optlen ;
	char *optp;
	struct connectdomain *cdp;
	int i,n,afd ;
	struct conversation *cd ;
	struct tab *p ;

	/* initialize */
	n = 0;
	FD_ZERO(&rd_fdset) ;
	FD_ZERO(&wr_fdset) ;
	signal (SIGTTOU, SIG_IGN) ;
	signal (SIGTTIN, SIG_IGN) ;
	signal (SIGINT, term) ;
	signal (SIGTERM, term) ;
	signal (SIGPIPE, sigpipe) ;
	if(setjmp(terminate)) goto on_error;
	openlog("connectd", LOG_CONS|LOG_ODELAY, LOG_AUTH);
	/* disassociate from tty pgrp */
	n = open ("/dev/tty", 2) ;
	ioctl(n,TIOCNOTTY, 0) ;
	close(n) ;

	/* make incoming request socket */
	sock = socket (AF_UNIX, SOCK_STREAM, 0) ;
	if (sock < 0) {
		perror("stream socket") ;
		exit(1) ;
	}
	rqsts.sun_family = AF_UNIX ;
	strcpy (rqsts.sun_path,"/dev/connect") ;
	if (bind (sock, &rqsts, sizeof (rqsts))) {
		perror ("bind /dev/connect") ;
		exit (1) ;
	}

	/* debugging ? */
	if ((argc <= 1) || strcmp(argv[1],"-d") != 0) {
		if (fork()) exit(0) ;
		close (0); close (1); close (2);
	} else debug = 1;

	/* build tables */
	itab = (struct tab *)calloc(1, sizeof(*itab));
	SCPYN(itab->line, tty3);
	itab->fd = -1;	/* do we have a fd open */
	itab->sock = -1; /* does someone else have this fd? */
	itab->gpid = 0; /* does getty have this fd? */

	itab->next = (struct tab *)calloc(1, sizeof(*itab));
	itab->next->fd = -1;	/* do we have a fd open */
	itab->next->sock = -1; /* does someone else have this fd? */
	itab->next->gpid = 0; /* does getty else have this fd? */
	SCPYN(itab->next->line, tty2);
	p = itab ;

	/* accept connection requests on socket */
	listen (sock, 5) ;
	FD_SET (sock, &rd_fdset) ;

	/* add requests from other lines */
	for (ALL) openline(p) ;

	/* service requests as they come in */
	for (;;) {
	    int s, ctrl, n;
	    fd_set readable, writeable;

	    readable = rd_fdset;
	    writeable = wr_fdset;
#ifdef notdef
for (i=0; i <20 ; i++) {
if (FD_ISSET(i,&readable)) fprintf(stderr, "rd%d ", i) ;
if (FD_ISSET(i,&writeable)) fprintf(stderr, "wr%d ", i) ;
}
fprintf(stderr, "?\n") ;
#endif
	    if ((n = select(21, &readable, &writeable,
		(fd_set *)0, &tv_2th )) <= 0) {
		    if (n < 0 && errno != EINTR)
				if (debug)
					perror ("select") ;
				else
					syslog(LOG_WARNING, "select: %m\n");
		    sleep(1);
		    continue;
	    }

		/* got a request, see who it is */
fprintf(stderr, "select %d\n", n) ;
for (i=0; i <20 ; i++) {
if (FD_ISSET(i,&readable))
fprintf(stderr, "rdsel%d ", i) ;
if (FD_ISSET(i,&writeable))
fprintf(stderr, "wrsel%d ", i) ;
}
fprintf(stderr, "\n") ;

		/* have we a new connection request? */
	    if (FD_ISSET(sock, &readable)) {
		msgsock = accept(sock, 0, 0) ;
		if (msgsock == -1) {
			perror ("accept") ;
			continue ;
		}
/*allocate a connection */
		convers[msgsock].co_sock = msgsock ;
		FD_SET (msgsock, &rd_fdset) ;
fprintf(stderr, "accept %d\n", msgsock) ;
	    }
		/* have we a incoming request */
for (p = itab; p ; p = p->next)
	    if (FD_ISSET(p->fd, &writeable)) {
		/* fork off getty after setting up line */
printf("do a getty on fd%d\n", p->fd) ;
if(p->sock >= 0) {  printf("on a conn?\n") ; continue; }
			i = fork ();
			if (i < 0) {
				perror("cd:fork") ;
				exit(1);
			}
			if (!i) {
				dup2(p->fd, 0);
				dup2(p->fd, 1);
				dup2(p->fd, 2);
				i = getdtablesize();
				for (n=3 ; n < i ; n++) close (n) ;
ioctl(0,TIOCYESTTY, 0) ;
			execl("/etc/getty", "getty", "std.1200", "-", 0) ;
				perror("exec");
				exit(1);
			} else {
p->gpid = i ;
				i = wait(&n) ;
printf("cd: waitgetty %d %d\n", i, n) ;
p->gpid = 0 ;
	closeline (p, 0) ;
rmut(p) ;
	sleep (1) ;
	openline (p) ;
			}
	    } ;
		;
		/* have we an existing socket request */
	    for (cd = convers; cd - convers < MAXCONNECTS ; cd++) {
		cdp = &cd->co_cd ;
	    	if (FD_ISSET(cd->co_sock, &readable)) {
fprintf(stderr, "recv %d\n", cd->co_sock) ;
			/* recieve connnection request message */
			rqst = rcvrequest(cd->co_sock, cd, &optp,
					&optlen, &afd) ;

/*fprintf(stderr, "rqst %d\n", rqst) ;*/
			if (rqst < 0) goto end_session ;

/*printf("cd:request %d ", rqst) ;*/

			/* process request */
			switch (rqst) {
		case CDNEWREQUEST:
				cd->co_rqst = rqst ;
/*printf("cd_family %d, cd_address %s, cd_alen %d\n",
	cdp->cd_family, cdp->cd_address, cdp->cd_alen) ;*/
/*if (optlen)
	printf("option:%s\n", optp);*/
			if (afd>= 0) {
				cd->co_errfd = afd ;
			} else cd->co_errfd = -1 ;

			cd->co_constatus = -1;
for (p = itab; p ; p = p->next)
	if (p->gpid == 0 && p->fd >= 0 && p->sock < 0) break;
if (!p) exit(0); /* return error can't find a line */
fprintf(stderr, "allocate fd%d line %s\n", p->fd, p->line) ;
ioctl(p->fd, TIOCSIGNCAR, 0) ;
p->errfd = cd->co_errfd;
p->sock = cd->co_sock ;
			i = fork ();
			if (i < 0) {
				perror("cd:fork") ;
				exit(1);
			}
			if (!i) {
				dup2(p->fd, 0);
				dup2(p->fd, 1);
				if (cd->co_errfd) dup2(cd->co_errfd,2);
				else close(2) ;
				i = getdtablesize();
				for (n=3 ; n < i ; n++) close (n) ;
				execl("con", "con", cdp->cd_address, 0) ;
				perror("exec");
				exit(1);
			} else {
				cd->co_pid = i ;
				i = wait(&n) ;
/*printf("cd: wait %d %d\n", i, n) ;*/
				if (n == 0) cd->co_constatus = n;
				else	{
	fprintf(stderr, "cd: con fails status %d\n", n) ;
					cd->co_constatus = (-1 <<16) | n ;
					closeline (p, 0) ;
				}
			}
if (p->fd >= 0) {
	fprintf(stderr, "cd: sending fd %d \n", p->fd) ;
	ioctl(p->fd, TIOCCIGNCAR, 0) ;
}
optlen = 0;

			resp = CDNEWRESPONSE ;
		/* send connnection response message */
		err = sendrequest(cd->co_sock, resp, cd, optp, optlen, p->fd) ;
		if(p->fd >= 0) closeline (p, 1) ;
		if (cd->co_constatus) goto end_session ;
		break ;

	case CDFINISHREQUEST:
for (p = itab; p ; p = p->next)
	if (p->sock == cd->co_sock) break;
if(!p) exit(0); /* return no such connection */
		p->fd = afd ;
fprintf(stderr, "cd: received fd %d \n", p->fd) ;
			cd->co_constatus = -1;
ioctl(p->fd, TIOCSIGNCAR, 0) ;
			i = fork ();
			if (i < 0) {
				perror("cd:fork") ;
				exit(1);
			}
			if (!i) {
				dup2(p->fd, 0);
				dup2(p->fd, 1);
				if (cd->co_errfd <= 0) dup2(cd->co_errfd,2);
				else close(2) ;
				i = getdtablesize();
				for (n=3 ; n < i ; n++) close (n) ;
				execl("con", "con", "drop" , 0) ;
				perror("exec");
				exit(1);
			} else {
				cd->co_pid = i ;
				i = wait(&n) ;
fprintf(stderr,"cd: wait %d %d\n", i, n) ;
				if (n == 0) cd->co_constatus = n;
				else	cd->co_constatus = (-1 <<16) | n ;
			}
fprintf(stderr,"cd: dropped \n") ;

		cd->co_rqst = resp = CDFINISHRESPONSE ;
		/* send connnection response message */
		err = sendrequest(cd->co_sock, resp, cd, 0, 0, 0) ;
		goto end_session;
		} 	/* end of switch */
		} ;  continue; 	/* end of if */

	end_session:
/*fprintf(stderr, "end_session\n") ;*/
		close (cd->co_errfd) ;
		FD_CLR (cd->co_sock, &rd_fdset) ;
		close (cd->co_sock) ;
		cd->co_sock = 0 ;
		if (p->fd >= 0) closeline (p, 0) ;
		sleep(1) ;
		openline (p) ;
	} /* end of conv for */
	}	/*end of foerever */
on_error:
	close (sock) ;
	unlink ("/dev/connect") ;
}

term() { struct tab *p;

	for (p = itab ; p ; p = p->next)
		if (p->gpid) kill (p->gpid, SIGHUP);
	longjmp (terminate);
}

sigpipe() { printf("SIGPIPE\n") ; fflush (stdout) ; longjmp (terminate); }

/*
 * open and prepare line for connectd
 */
openline(p) struct tab *p; {
	char ttyn[32]; int n;
	
	/* open the bastard */
	strcpy (ttyn, "/dev/");
	strcat (ttyn, p->line) ;
	p->fd = open (ttyn, O_RDWR|O_NDELAY) ;

	/* disassociate from our pgrp */
	n = open ("/dev/tty", O_RDWR|O_NDELAY) ;
	ioctl (n, TIOCNOTTY, 0) ;
	close(n) ;

	/* mark 'em to be watched for carrier */
	FD_SET (p->fd, &wr_fdset) ;

	/* if set in a still open state */
	ioctl(p->fd, TIOCCIGNCAR, 0) ;

	if (debug) fprintf(stderr, "openline: %s: fd %d\n", p->line,  p->fd) ;
}

closeline(p, i) struct tab *p; {

	if (debug) fprintf(stderr, "closeline: %s: fd %d ", p->line,  p->fd) ;

	close (p->fd) ;
	FD_CLR (p->fd, &wr_fdset) ;
	p->fd = -1 ;
	if (i) {
		if (debug) fprintf(stderr, "remove from use\n") ;
		return ;
	}

	if (debug) fprintf(stderr, "entirely\n") ;
	if (p->gpid) kill (p->gpid, SIGKILL); /* no mercy */
	p->gpid = 0 ;

	if(p->sock >= 0) close (p->sock);
	p->sock = -1 ;
}

#ifdef notdef
struct	sigvec rvec = { reset, sigmask(SIGHUP), 0 };


main(argc, argv)
	char **argv;
{
	int howto, oldhowto;

	time0 = time(0);
	if (argc > 1 && argv[1][0] == '-') {
		char *cp;

		howto = 0;
		cp = &argv[1][1];
		while (*cp) switch (*cp++) {
		case 'a':
			howto |= RB_ASKNAME;
			break;
		case 's':
			howto |= RB_SINGLE;
			break;
		}
	} else {
		howto = RB_SINGLE;
	}
	openlog("connectd", LOG_CONS|LOG_ODELAY, LOG_AUTH);
	sigvec(SIGTERM, &rvec, (struct sigvec *)0);
	signal(SIGTSTP, idle);
	signal(SIGSTOP, SIG_IGN);
	signal(SIGTTIN, SIG_IGN);
	signal(SIGTTOU, SIG_IGN);
	(void) setjmp(sjbuf);
	for (EVER) {
		oldhowto = howto;
		howto = RB_SINGLE;
		if (setjmp(shutpass) == 0)
			shutdown();
		if (oldhowto & RB_SINGLE)
			single();
		if (runcom(oldhowto) == 0) 
			continue;
		merge();
		multiple();
	}
}

int	shutreset();

shutdown()
{