x29d.c

早期freebsd实现

/*
 * X.29 server
 *
 * Frank Pronk (...!ubc-vision!pronk)
 * April, September 1984
 *
 * Laboratory for Computational Vision
 * University of British Columbia
 * Copyright (c)
 */

#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <netccitt/x25.h>

#include <errno.h>
#include <netdb.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/termios.h>
#include <paths.h>

#include "../h/x29.h"

#define BUFSIZ		1024
#define MAXARGS		10	/* maximum size of server argument list */

#define X25NET		0	/* no ITI parameters */
#define CCITT1978	1	/* 1978 CCITT standard parameter set */
#define CCITT1980	2	/* 1980 CCITT standard parameter set */


char	pibuf[BUFSIZ], fibuf[BUFSIZ];
int	pty, net;
extern	char **environ;
extern	int errno;
char	line[MAXPATHLEN];
char	console[] = "/dev/console";
short	packet_size;
short	debug;
char	*tracefn;		/* trace file name */
char	*server;
short	send_banner;
struct	termios pt, old_pt;
struct	sockaddr_x25 sock;

int	reapchild();
struct	net *lookup ();

char	ccitt1978_prof[] = {		/* initial profile */
	Q_BIT,	X29_SET_AND_READ_PARMS,
	X29_ECHO_CODE,			1,	/* echo on */
	X29_FORWARDING_SIGNAL_CODE,	126,	/* forward on all cntl */
	X29_IDLE_TIMER_CODE,		0,	/* off */
	X29_AUX_DEV_CONTROL_CODE,	0,	/* off */
	X29_RECEIVE_NET_MSGS_CODE,	1,	/* xmit network msgs */
	X29_BREAK_PROCEDURE_CODE,	21,
	X29_PADDING_CODE,		0,	/* off */
	X29_LINE_FOLDING_CODE,		0,	/* off */
	X29_TRANSMISSION_SPEED_CODE,	0,
	X29_XON_XOFF_CODE,		1,	/* enable XON/XOFF */
};

char	ccitt1980_prof[] = {		/* initial profile */
	Q_BIT,	X29_SET_AND_READ_PARMS,
	X29_ECHO_CODE,			1,	/* echo on */
	X29_FORWARDING_SIGNAL_CODE,	126,	/* forward on all cntl */
	X29_IDLE_TIMER_CODE,		0,	/* off */
	X29_AUX_DEV_CONTROL_CODE,	0,	/* off */
	X29_RECEIVE_NET_MSGS_CODE,	1,	/* xmit network msgs */
	X29_BREAK_PROCEDURE_CODE,	21,
	X29_PADDING_CODE,		0,	/* off */
	X29_LINE_FOLDING_CODE,		0,	/* off */
	X29_TRANSMISSION_SPEED_CODE,	0,
	X29_XON_XOFF_CODE,		1,	/* enable XON/XOFF */

	X29_LF_AFTER_CR,		4,	/* lf after cr from terminal */
	X29_EDITING,			1,	/* on */
	X29_CHARACTER_DELETE,		CERASE,
	X29_LINE_DELETE,		CKILL,
	X29_LINE_DISPLAY,		CRPRNT,
};

char	datapac_prof[] = {		/* Canadian X.25 network */
	Q_BIT,	X29_SET_AND_READ_PARMS,
	X29_ECHO_CODE,			1,	/* echo on */
	X29_FORWARDING_SIGNAL_CODE,	126,	/* forward on all cntl */
	X29_IDLE_TIMER_CODE,		0,	/* off */
	X29_AUX_DEV_CONTROL_CODE,	0,	/* off */
	X29_RECEIVE_NET_MSGS_CODE,	1,	/* xmit network msgs */
	X29_BREAK_PROCEDURE_CODE,	21,
	X29_PADDING_CODE,		0,	/* off */
	X29_LINE_FOLDING_CODE,		0,	/* off */
	X29_TRANSMISSION_SPEED_CODE,	0,
	X29_XON_XOFF_CODE,		1,	/* enable XON/XOFF */

	X29_LF_AFTER_CR,		4,	/* lf after cr from terminal */
	X29_EDITING,			1,	/* on */
	X29_CHARACTER_DELETE,		CERASE,
	X29_LINE_DELETE,		CKILL,
	X29_LINE_DISPLAY,		CRPRNT,

	/*
	 * This rubbish can be removed when Datapac
	 * adopts the 1980 standard parameter set.
	 */

	0,				0,	/* national parameter marker */
	123,				0,	/* parity off */
};

struct	net {
	char	*n_name;	/* generic name */
	short	n_type;		/* see defines above */
	char	*n_profile;	/* initial profile */
	short	n_proflen;	/* length of n_profile */
} *netp, nets[] = {
	"x.25",		X25NET,		0,		0,
	"1978",		CCITT1978,	ccitt1978_prof,	sizeof(ccitt1978_prof),
	"ccitt1978",	CCITT1978,	ccitt1978_prof,	sizeof(ccitt1978_prof),
	"1980",		CCITT1980,	ccitt1980_prof,	sizeof(ccitt1980_prof),
	"ccitt1980",	CCITT1980,	ccitt1980_prof,	sizeof(ccitt1980_prof),
	"datapac",	CCITT1980,	datapac_prof,	sizeof(datapac_prof),
	0,		0,		0,		0
};

main(argc, argv)
register char **argv;
{
	register int s, pid;
	register char *p;

	/*
	 * If this host doesn't support X.25, give up.
	 */
	s = socket(AF_CCITT, SOCK_STREAM, 0);
	if (s < 0 && errno == EPROTONOSUPPORT)
		fatal(2, "X.25 is not supported on this machine");
	close(s);
	netp = lookup ("ccitt1978");
	sock.x25_family = AF_CCITT;
	sock.x25_len = sizeof(sock);
	sock.x25_opts.op_flags = X25_MQBIT;
	sock.x25_udata[0] = ITI_CALL;
	sock.x25_udlen = 4;

	for (argv++; argc > 1; argc--, argv++)
		if (**argv == '-')
			for (p = *argv+1; *p; p++)
			switch (*p) {
			case 'b':
				send_banner++;
				break;

			case 'c':
				if (argc > 1) {
					argc--; argv++;
					if ((netp = lookup (*argv)) == 0)
						fatal(1, "Unknown network type");
				}
				break;

			case 'p':
				if (argc > 1) {
					argc--; argv++;
					strcpy (sock.x25_udata, *argv);
				}
				break;

			case 'r':
				sock.x25_opts.op_flags |= X25_REVERSE_CHARGE;
				break;

			case 'd':
				debug++;
				break;

			case 't':
				if (argc > 1) {
					argc--; argv++;
					tracefn = *argv;
				}
				else fatal(1, "missing trace file");
				break;

			default:
				fatal (1, "usage: x29d -b -c nettype -p protocol -r -t trace_file server");
			}
		else
			server = *argv;
	if (server == 0)
		fatal (1, "no server specified");
	if (debug == 0)
		daemon(0, 0);

	while ((s = socket(AF_CCITT, SOCK_STREAM, 0)) < 0)
		sleep(60);
	while (bind(s, (caddr_t)&sock, sizeof (sock)) < 0)
		sleep(60);
	signal(SIGCHLD, reapchild);
	listen(s, 5);

	for (;;) {
		struct sockaddr_x25 from;
		int fromlen = sizeof (from);

		if ((net = accept(s, (caddr_t)&from, &fromlen)) < 0) {
			if (errno != EINTR)
				sleep (60);
			continue;
		}
		while ((pid = fork()) < 0)
			sleep(60);
		if (pid == 0) {
			signal(SIGCHLD, SIG_DFL);
			doit(&from);
		}
		close(net);
	}
	/*NOTREACHED*/
}

struct net *
lookup (name)
char *name;
{
	register struct net *np;

	for (np = nets; np->n_name; np++)
		if (strcmp (np->n_name, name) == 0)
			return (np);
	return (0);
}

reapchild()
{
	union wait status;

	while (wait3(&status, WNOHANG, 0) > 0)
		;
}

char	*envinit[] = { "TERM=ccitt", 0 };
int	cleanup();
struct termios term;

/*
 * Get a pty, scan input lines.
 */
doit(who)
struct sockaddr_x25 *who;
{
	register char *cp;
	int i, p, t;

	packet_size = 1 << who->x25_opts.op_psize;
	i = forkpty(&pty, line, &term, 0);
	if (i > 0)
		x29d();
	if (i < 0)
		fatalperror("fork", errno);
	environ = envinit;
	call_server (who);
	/*NOTREACHED*/
}

call_server (who)
struct sockaddr_x25 *who;
{
	register struct hostent *hp = 0;
	register char *p, **ap;
	char *args[MAXARGS];
	struct stat st;
	struct hostent *getx25hostbyaddr();
	int ccitt = 0;

	p = server;
	while (*p && *p != ' ' && *p != '\t')	/* split program from args */
		p++;
	if (*p)
		*p++ = '\0';
	ap = args;
	while (*p) {
		while (*p == ' ' || *p == '\t')
			p++;
		if (ap < &args[MAXARGS-2])
			*ap++ = p;
		if (strcmp(p, "-ccitt") == 0)
			ccitt = 1;
		while (*p && *p != ' ' && *p != '\t')
			p++;
		if (*p)
			*p++ = '\0';
	}
	if (stat (server, &st) < 0)
		fatalperror (server, errno);
	/*
	 * For security: if running as root, switch to user
	 * and group id of server.  This prevents privately
	 * maintainted or bogus servers from getting super-
	 * user permissions.
	 */
	if (getuid() == 0) {
		setgid (st.st_gid);
		setuid (st.st_uid);
	}
	if (hp = getx25hostbyaddr (who->x25_addr))
		*ap++ = hp->h_name;
	else
		*ap++ = (char *)who->x25_addr;
	/*
	 * If the -ccitt flag was given, add another argument
	 * to tell login if charging is being reversed or not.
	 */
	if (ccitt)
		*ap++ = (who->x25_opts.op_flags & X25_REVERSE_CHARGE) ? "y" : "n";
	*ap = 0;
	execv (server, args);
	fatalperror (server, errno);
	/*NOTREACHED*/
}

fatal(f, msg)
	int f;
	char *msg;
{
	register char *p;
	char buf[BUFSIZ], *index();

	p = buf;
	if (f == net)
		*p++ = 0;
	strcpy(p, "x29d: ");
	strcat(p, msg);
	strcat(p, "\n");
	(void) write(f, p, (index(p, '\n')-p)+1);
	exit(1);
}

fatalperror(msg, err)
char *msg;
{
	char buf[BUFSIZ];
	extern char *sys_errlist[];

	strcpy(buf, msg);
	strcat(buf, ": ");
	strcat(buf, sys_errlist[err]);
	fatal(net, buf);
}

/*
 * Main loop.  Select from pty and network, and
 * hand data to iti receiver.
 */
x29d()
{
	register int pcc, fcc, cc;
	register char *fbp;
	int pgrp, x25_interrupt(), on = 1;
	char hostname[32];

	ioctl(net, FIONBIO, (char *)&on);
	ioctl(pty, FIONBIO, (char *)&on);
	/*ioctl(pty, TIOCREMECHO, (char *)&on);	/* enable special pty mode */
	/* new equivalent is no processing in pty, no echo, but let
	   user set modes and have either remote end do line mode processing
	   or do it in daemon */
	ioctl(pty, TIOCEXT, (char *)&on);
	ioctl(pty, TIOCPKT, (char *)&on);