usr.bin/telnet/commands.c

#pragma ident	"%Z%%M%	%I%	%E% SMI"

/*
 * Copyright (c) 1988, 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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.
 *
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#ifndef lint
static char sccsid[] = "@(#)commands.c	8.1 (Berkeley) 6/6/93";
#endif /* not lint */

#include <sys/param.h>
#include <sys/file.h>
#include <sys/socket.h>
#include <sys/sysmacros.h>
#include <netinet/in.h>

#include <signal.h>
#include <netdb.h>
#include <ctype.h>
#include <pwd.h>
#include <errno.h>
#include <strings.h>

#include <arpa/telnet.h>
#include <arpa/inet.h>

#include "general.h"

#include "ring.h"

#include "externs.h"
#include "defines.h"
#include "types.h"

extern	char *telnet_krb5_realm;
extern	void krb5_profile_get_options(char *, char *,
		profile_options_boolean*);

#include <k5-int.h>
#include <profile/prof_int.h>

profile_options_boolean config_file_options[] = {
	{ "forwardable", &forwardable_flag, 0},
	{ "forward", &forward_flag, 0},
	{ "encrypt", &encrypt_flag, 0 },
	{ "autologin", &autologin, 0 },
	{ NULL, NULL, 0}
};

#include <netinet/ip.h>

/*
 * Number of maximum IPv4 gateways user can specify. This number is limited by
 * the maximum size of the IPv4 options in the IPv4 header.
 */
#define	MAX_GATEWAY	8
/*
 * Number of maximum IPv6 gateways user can specify. This number is limited by
 * the maximum header extension length of the IPv6 routing header.
 */
#define	MAX_GATEWAY6	127
#define	MAXMAX_GATEWAY	MAX(MAX_GATEWAY, MAX_GATEWAY6)

/*
 * Depending on the address resolutions of the target and gateways,
 * we determine which addresses of the target we'll try connecting to.
 */
#define	ALL_ADDRS	0	/* try all addrs of target */
#define	ONLY_V4		1	/* try only IPv4 addrs of target */
#define	ONLY_V6		2	/* try only IPv6 addrs of target */

#if defined(USE_TOS)
int tos = -1;
#endif

char	*hostname;
static char _hostname[MAXHOSTNAMELEN];

static int send_tncmd(void (*func)(), char *, char *);
static void call(int n_ptrs, ...);
static int cmdrc(char *, char *);

typedef struct {
	char	*name;		/* command name */
	char	*help;		/* help string (NULL for no help) */
	int	(*handler)();	/* routine which executes command */
	int	needconnect;	/* Do we need to be connected to execute? */
} Command;

/*
 * storage for IPv6 and/or IPv4 addresses of gateways
 */
struct gateway {
	struct in6_addr	gw_addr6;
	struct in_addr	gw_addr;
};

/*
 * IPv4 source routing option.
 * In order to avoid padding for the alignment of IPv4 addresses, ipsr_addrs
 * is defined as a 2-D array of uint8_t, instead of 1-D array of struct in_addr.
 * If it were defined as "struct in_addr ipsr_addrs[1]", "ipsr_ptr" would be
 * followed by one byte of padding to avoid misaligned struct in_addr.
 */
struct ip_sourceroute {
	uint8_t ipsr_code;
	uint8_t ipsr_len;
	uint8_t ipsr_ptr;
	/* up to 9 IPv4 addresses */
	uint8_t ipsr_addrs[1][sizeof (struct in_addr)];
};

static char *line = NULL;
static unsigned linesize = 0;
static int margc;
static char **margv = NULL;
static unsigned margvlen = 0;
static int doing_rc = 0;   /* .telnetrc file is being read and processed */

static void
Close(int *fd)
{
	if (*fd != -1) {
		(void) close(*fd);
		*fd = -1;
	}
}

static void
Free(char **p)
{
	if (*p != NULL) {
		free(*p);
		*p = NULL;
	}
}

static void
FreeHostnameList(char *list[])
{
	unsigned i;
	for (i = 0; i <= MAXMAX_GATEWAY && list[i] != NULL; i++)
		Free(&list[i]);
}

#define	MARGV_CHUNK_SIZE 8

static void
set_argv(str)
char *str;
{
	if (margc == margvlen) {
		char **newmargv;

		margvlen += MARGV_CHUNK_SIZE;

		if ((newmargv = realloc(margv, margvlen * sizeof (char *)))
			== NULL)
			ExitString("telnet: no space for arguments",
				EXIT_FAILURE);

		margv = newmargv;
	}

	margv[margc] = str;
	if (str != NULL)
		margc++;
}

static void
makeargv()
{
	char *cp, *cp2, c;
	boolean_t shellcmd = B_FALSE;

	margc = 0;
	cp = line;
	if (*cp == '!') {		/* Special case shell escape */
		set_argv("!");		/* No room in string to get this */
		cp++;
		shellcmd = B_TRUE;
	}
	while ((c = *cp) != '\0') {
		register int inquote = 0;
		while (isspace(c))
			c = *++cp;
		if (c == '\0')
			break;
		set_argv(cp);
		/*
		 * For the shell escape, put the rest of the line, less
		 * leading space, into a single argument, breaking out from
		 * the loop to prevent the rest of the line being split up
		 * into smaller arguments.
		 */
		if (shellcmd)
			break;
		for (cp2 = cp; c != '\0'; c = *++cp) {
			if (inquote) {
				if (c == inquote) {
					inquote = 0;
					continue;
				}
			} else {
				if (c == '\\') {
					if ((c = *++cp) == '\0')
						break;
				} else if (c == '"') {
					inquote = '"';
					continue;
				} else if (c == '\'') {
					inquote = '\'';
					continue;
				} else if (isspace(c))
					break;
			}
			*cp2++ = c;
		}
		*cp2 = '\0';
		if (c == '\0')
			break;
		cp++;
	}
	set_argv((char *)NULL);
}

/*
 * Make a character string into a number.
 *
 * Todo:  1.  Could take random integers (12, 0x12, 012, 0b1).
 */

	static int
special(s)
	register char *s;
{
	register char c;
	char b;

	switch (*s) {
	case '^':
		b = *++s;
		if (b == '?') {
		    c = b | 0x40;		/* DEL */
		} else {
		    c = b & 0x1f;
		}
		break;
	default:
		c = *s;
		break;
	}
	return (c);
}

/*
 * Construct a control character sequence
 * for a special character.
 */
	static char *
control(c)
	register cc_t c;
{
	static char buf[5];
	/*
	 * The only way I could get the Sun 3.5 compiler
	 * to shut up about
	 *	if ((unsigned int)c >= 0x80)
	 * was to assign "c" to an unsigned int variable...
	 * Arggg....
	 */
	register unsigned int uic = (unsigned int)c;

	if (uic == 0x7f)
		return ("^?");
	if (c == (cc_t)_POSIX_VDISABLE) {
		return ("off");
	}
	if (uic >= 0x80) {
		buf[0] = '\\';
		buf[1] = ((c>>6)&07) + '0';
		buf[2] = ((c>>3)&07) + '0';
		buf[3] = (c&07) + '0';
		buf[4] = 0;
	} else if (uic >= 0x20) {
		buf[0] = c;
		buf[1] = 0;
	} else {
		buf[0] = '^';
		buf[1] = '@'+c;
		buf[2] = 0;
	}
	return (buf);
}

/*
 * Same as control() except that its only used for escape handling, which uses
 * _POSIX_VDISABLE differently and is aided by the use of the state variable
 * escape_valid.
 */
	static char *
esc_control(c)
	register cc_t c;
{
	static char buf[5];
	/*
	 * The only way I could get the Sun 3.5 compiler
	 * to shut up about
	 *	if ((unsigned int)c >= 0x80)
	 * was to assign "c" to an unsigned int variable...
	 * Arggg....
	 */
	register unsigned int uic = (unsigned int)c;

	if (escape_valid == B_FALSE)
		return ("off");
	if (uic == 0x7f)
		return ("^?");
	if (uic >= 0x80) {
		buf[0] = '\\';
		buf[1] = ((c>>6)&07) + '0';
		buf[2] = ((c>>3)&07) + '0';
		buf[3] = (c&07) + '0';
		buf[4] = 0;
	} else if (uic >= 0x20) {
		buf[0] = c;
		buf[1] = 0;
	} else {
		buf[0] = '^';
		buf[1] = '@'+c;
		buf[2] = 0;
	}
	return (buf);
}

/*
 *	The following are data structures and routines for
 *	the "send" command.
 *
 */

struct sendlist {
	char	*name;		/* How user refers to it (case independent) */
	char	*help;		/* Help information (0 ==> no help) */
	int	needconnect;	/* Need to be connected */
	int	narg;		/* Number of arguments */
	int	(*handler)();	/* Routine to perform (for special ops) */
	int	nbyte;		/* Number of bytes to send this command */
	int	what;		/* Character to be sent (<0 ==> special) */
};


static int send_esc(void);
static int send_help(void);
static int send_docmd(char *);
static int send_dontcmd(char *);
static int send_willcmd(char *);
static int send_wontcmd(char *);

static struct sendlist Sendlist[] = {
	{ "ao",	"Send Telnet Abort output",		1, 0, 0, 2, AO },
	{ "ayt", "Send Telnet 'Are You There'",		1, 0, 0, 2, AYT },
	{ "b", 0,					1, 0, 0, 2, BREAK },
	{ "br", 0,					1, 0, 0, 2, BREAK },
	{ "break", 0,					1, 0, 0, 2, BREAK },
	{ "brk", "Send Telnet Break",			1, 0, 0, 2, BREAK },
	{ "ec",	"Send Telnet Erase Character",		1, 0, 0, 2, EC },
	{ "el",	"Send Telnet Erase Line",		1, 0, 0, 2, EL },
	{ "escape", "Send current escape character",	1, 0, send_esc, 1, 0 },
	{ "ga",	"Send Telnet 'Go Ahead' sequence",	1, 0, 0, 2, GA },
	{ "ip",	"Send Telnet Interrupt Process",	1, 0, 0, 2, IP },
	{ "intp", 0,					1, 0, 0, 2, IP },
	{ "interrupt", 0,				1, 0, 0, 2, IP },
	{ "intr",	0,				1, 0, 0, 2, IP },
	{ "nop", "Send Telnet 'No operation'",		1, 0, 0, 2, NOP },
	{ "eor", "Send Telnet 'End of Record'",		1, 0, 0, 2, EOR },
	{ "abort", "Send Telnet 'Abort Process'",	1, 0, 0, 2, ABORT },
	{ "susp", "Send Telnet 'Suspend Process'",	1, 0, 0, 2, SUSP },
	{ "eof", "Send Telnet End of File Character",	1, 0, 0, 2, xEOF },
	{ "synch", "Perform Telnet 'Synch operation'",	1, 0, dosynch, 2, 0 },
	{ "getstatus", "Send request for STATUS", 1, 0, get_status, 6, 0 },
	{ "?",	"Display send options",			0, 0, send_help, 0, 0 },
	{ "help",	0,				0, 0, send_help, 0, 0 },
	{ "do",	0,				0, 1, send_docmd, 3, 0 },
	{ "dont", 0,				0, 1, send_dontcmd, 3, 0 },
	{ "will", 0,				0, 1, send_willcmd, 3, 0 },
	{ "wont", 0,				0, 1, send_wontcmd, 3, 0 },
	{ 0 }
};

#define	GETSEND(name) ((struct sendlist *)genget(name, (char **)Sendlist, \
				sizeof (struct sendlist)))

static int
sendcmd(argc, argv)
	int  argc;
	char **argv;
{
	int count;	/* how many bytes we are going to need to send */
	int i;
	struct sendlist *s;	/* pointer to current command */
	int success = 0;
	int needconnect = 0;

	if (argc < 2) {
		(void) printf(
		    "need at least one argument for 'send' command\n");
		(void) printf("'send ?' for help\n");
		return (0);
	}
	/*
	 * First, validate all the send arguments.
	 * In addition, we see how much space we are going to need, and
	 * whether or not we will be doing a "SYNCH" operation (which
	 * flushes the network queue).
	 */
	count = 0;
	for (i = 1; i < argc; i++) {
		s = GETSEND(argv[i]);
		if (s == 0) {
			(void) printf("Unknown send argument '%s'\n'send ?' "
			    "for help.\n", argv[i]);
			return (0);
		} else if (Ambiguous(s)) {
			(void) printf("Ambiguous send argument '%s'\n'send ?' "
			    "for help.\n", argv[i]);
			return (0);
		}
		if (i + s->narg >= argc) {
			(void) fprintf(stderr,
			    "Need %d argument%s to 'send %s' "
			    "command.  'send %s ?' for help.\n",
			    s->narg, s->narg == 1 ? "" : "s", s->name, s->name);
			return (0);
		}
		count += s->nbyte;
		if (s->handler == send_help) {
			(void) send_help();
			return (0);
		}

		i += s->narg;
		needconnect += s->needconnect;
	}
	if (!connected && needconnect) {
		(void) printf("?Need to be connected first.\n");
		(void) printf("'send ?' for help\n");
		return (0);
	}
	/* Now, do we have enough room? */
	if (NETROOM() < count) {
		(void) printf("There is not enough room in the buffer "
		    "TO the network\n");
		(void) printf(
		    "to process your request.  Nothing will be done.\n");
		(void) printf("('send synch' will throw away most "
		    "data in the network\n");
		(void) printf("buffer, if this might help.)\n");
		return (0);
	}
	/* OK, they are all OK, now go through again and actually send */
	count = 0;
	for (i = 1; i < argc; i++) {
		if ((s = GETSEND(argv[i])) == 0) {
			(void) fprintf(stderr,
			    "Telnet 'send' error - argument disappeared!\n");
			(void) quit();
			/*NOTREACHED*/
		}
		if (s->handler) {
			count++;
			success += (*s->handler)((s->narg > 0) ? argv[i+1] : 0,
			    (s->narg > 1) ? argv[i+2] : 0);
			i += s->narg;
		} else {
			NET2ADD(IAC, s->what);
			printoption("SENT", IAC, s->what);
		}
	}
	return (count == success);
}

static int
send_esc()
{
	NETADD(escape);
	return (1);
}

static int
send_docmd(name)
	char *name;
{
	return (send_tncmd(send_do, "do", name));
}

static int
send_dontcmd(name)
	char *name;
{
	return (send_tncmd(send_dont, "dont", name));
}

static int
send_willcmd(name)
	char *name;
{
	return (send_tncmd(send_will, "will", name));
}

static int
send_wontcmd(name)
	char *name;
{
	return (send_tncmd(send_wont, "wont", name));
}

int
send_tncmd(func, cmd, name)
	void	(*func)();
	char	*cmd, *name;
{
	char **cpp;
	extern char *telopts[];
	register int val = 0;

	if (isprefix(name, "help") || isprefix(name, "?")) {
		register int col, len;

		(void) printf("Usage: send %s <value|option>\n", cmd);
		(void) printf("\"value\" must be from 0 to 255\n");
		(void) printf("Valid options are:\n\t");

		col = 8;
		for (cpp = telopts; *cpp; cpp++) {
			len = strlen(*cpp) + 3;
			if (col + len > 65) {
				(void) printf("\n\t");
				col = 8;
			}
			(void) printf(" \"%s\"", *cpp);
			col += len;
		}
		(void) printf("\n");
		return (0);
	}
	cpp = (char **)genget(name, telopts, sizeof (char *));
	if (Ambiguous(cpp)) {
		(void) fprintf(stderr,
		    "'%s': ambiguous argument ('send %s ?' for help).\n",
		    name, cmd);
		return (0);
	}
	if (cpp) {
		val = cpp - telopts;
	} else {
		register char *cp = name;

		while (*cp >= '0' && *cp <= '9') {
			val *= 10;
			val += *cp - '0';
			cp++;
		}
		if (*cp != 0) {
			(void) fprintf(stderr,
			    "'%s': unknown argument ('send %s ?' for help).\n",
			    name, cmd);
			return (0);
		} else if (val < 0 || val > 255) {
			(void) fprintf(stderr,
			    "'%s': bad value ('send %s ?' for help).\n",
			    name, cmd);
			return (0);
		}
	}
	if (!connected) {
		(void) printf("?Need to be connected first.\n");
		return (0);
	}
	(*func)(val, 1);
	return (1);
}

static int
send_help()
{
	struct sendlist *s;	/* pointer to current command */
	for (s = Sendlist; s->name; s++) {
		if (s->help)
			(void) printf("%-15s %s\n", s->name, s->help);
	}
	return (0);
}

/*
 * The following are the routines and data structures referred
 * to by the arguments to the "toggle" command.
 */

static int
lclchars()
{
	donelclchars = 1;
	return (1);
}

static int
togdebug()
{
	if (net > 0 &&
	    (SetSockOpt(net, SOL_SOCKET, SO_DEBUG, debug)) < 0) {
		perror("setsockopt (SO_DEBUG)");
	}
	return (1);
}


static int
togcrlf()
{
	if (crlf) {
		(void) printf(
		    "Will send carriage returns as telnet <CR><LF>.\n");
	} else {
		(void) printf(
		    "Will send carriage returns as telnet <CR><NUL>.\n");
	}
	return (1);
}

static int binmode;

static int
togbinary(val)
	int val;
{
	donebinarytoggle = 1;

	if (val >= 0) {
		binmode = val;
	} else {
		if (my_want_state_is_will(TELOPT_BINARY) &&
		    my_want_state_is_do(TELOPT_BINARY)) {
			binmode = 1;
		} else if (my_want_state_is_wont(TELOPT_BINARY) &&
		    my_want_state_is_dont(TELOPT_BINARY)) {
			binmode = 0;
		}
		val = binmode ? 0 : 1;
	}

	if (val == 1) {
		if (my_want_state_is_will(TELOPT_BINARY) &&
		    my_want_state_is_do(TELOPT_BINARY)) {
			(void) printf("Already operating in binary mode "
			    "with remote host.\n");
		} else {
			(void) printf(
			    "Negotiating binary mode with remote host.\n");
			tel_enter_binary(3);
		}
	} else {
		if (my_want_state_is_wont(TELOPT_BINARY) &&
		    my_want_state_is_dont(TELOPT_BINARY)) {
			(void) printf("Already in network ascii mode "
			    "with remote host.\n");
		} else {
			(void) printf("Negotiating network ascii mode "
			    "with remote host.\n");
			tel_leave_binary(3);
		}
	}
	return (1);
}

static int
togrbinary(val)
	int val;
{
	donebinarytoggle = 1;

	if (val == -1)
		val = my_want_state_is_do(TELOPT_BINARY) ? 0 : 1;

	if (val == 1) {
		if (my_want_state_is_do(TELOPT_BINARY)) {
			(void) printf("Already receiving in binary mode.\n");
		} else {
			(void) printf("Negotiating binary mode on input.\n");
			tel_enter_binary(1);
		}
	} else {
		if (my_want_state_is_dont(TELOPT_BINARY)) {
			(void) printf(
			    "Already receiving in network ascii mode.\n");
		} else {
			(void) printf(
			    "Negotiating network ascii mode on input.\n");
			    tel_leave_binary(1);
		}
	}
	return (1);
}

static int
togxbinary(val)
	int val;
{
	donebinarytoggle = 1;

	if (val == -1)
		val = my_want_state_is_will(TELOPT_BINARY) ? 0 : 1;

	if (val == 1) {
		if (my_want_state_is_will(TELOPT_BINARY)) {
			(void) printf("Already transmitting in binary mode.\n");
		} else {
			(void) printf("Negotiating binary mode on output.\n");
			tel_enter_binary(2);
		}
	} else {
		if (my_want_state_is_wont(TELOPT_BINARY)) {
			(void) printf(
			    "Already transmitting in network ascii mode.\n");
		} else {
			(void) printf(
			    "Negotiating network ascii mode on output.\n");
			tel_leave_binary(2);
		}
	}
	return (1);
}


static int togglehelp(void);
extern int auth_togdebug(int);

struct togglelist {
	char	*name;		/* name of toggle */
	char	*help;		/* help message */
	int	(*handler)();	/* routine to do actual setting */
	int	*variable;
	char	*actionexplanation;
};

static struct togglelist Togglelist[] = {
	{ "autoflush",
	"flushing of output when sending interrupt characters",
	    0,
		&autoflush,
		    "flush output when sending interrupt characters" },
	{ "autosynch",
	"automatic sending of interrupt characters in urgent mode",
	    0,
		&autosynch,
		    "send interrupt characters in urgent mode" },
	{ "autologin",
	"automatic sending of login and/or authentication info",
	    0,
		&autologin,
		    "send login name and/or authentication information" },
	{ "authdebug",
	"authentication debugging",
	    auth_togdebug,
		0,
		    "print authentication debugging information" },
	{ "autoencrypt",
	"automatic encryption of data stream",
	    EncryptAutoEnc,
		0,
		    "automatically encrypt output" },
	{ "autodecrypt",
	"automatic decryption of data stream",
	    EncryptAutoDec,
		0,
		    "automatically decrypt input" },
	{ "verbose_encrypt",
	"verbose encryption output",
	    EncryptVerbose,
		0,
		    "print verbose encryption output" },
	{ "encdebug",
	"encryption debugging",
	    EncryptDebug,
		0,
		    "print encryption debugging information" },
	{ "skiprc",
	"don't read ~/.telnetrc file",
	    0,
		&skiprc,
		    "skip reading of ~/.telnetrc file" },
	{ "binary",
	"sending and receiving of binary data",
	    togbinary,
		0,
		    0 },
	{ "inbinary",
	"receiving of binary data",
	    togrbinary,
		0,
		    0 },
	{ "outbinary",
	"sending of binary data",
	    togxbinary,
		0,
		    0 },
	{ "crlf",
	"sending carriage returns as telnet <CR><LF>",
	    togcrlf,
		&crlf,
		    0 },
	{ "crmod",
	"mapping of received carriage returns",
	    0,
		&crmod,
		    "map carriage return on output" },
	{ "localchars",
	"local recognition of certain control characters",
	    lclchars,
		&localchars,
		    "recognize certain control characters" },
	{ " ", "", 0 },		/* empty line */
	{ "debug",
	"debugging",
	    togdebug,
		&debug,
		    "turn on socket level debugging" },
	{ "netdata",
	"printing of hexadecimal network data (debugging)",
	    0,
		&netdata,
		    "print hexadecimal representation of network traffic" },
	{ "prettydump",
	"output of \"netdata\" to user readable format (debugging)",
	    0,
		&prettydump,
		    "print user readable output for \"netdata\"" },
	{ "options",
	"viewing of options processing (debugging)",
	    0,
		&showoptions,
		    "show option processing" },
	{ "termdata",
	"(debugging) toggle printing of hexadecimal terminal data",
	    0,
		&termdata,
		    "print hexadecimal representation of terminal traffic" },
	{ "?",
	0,
	    togglehelp },
	{ "help",
	0,
	    togglehelp },
	{ 0 }
};

static int
togglehelp()
{
	struct togglelist *c;

	for (c = Togglelist; c->name; c++) {
		if (c->help) {
			if (*c->help)
				(void) printf(
					"%-15s toggle %s\n", c->name, c->help);
			else
				(void) printf("\n");
		}
	}
	(void) printf("\n");
	(void) printf("%-15s %s\n", "?", "display help information");
	return (0);
}

static void
settogglehelp(set)
	int set;
{
	struct togglelist *c;

	for (c = Togglelist; c->name; c++) {
		if (c->help) {
			if (*c->help)
				(void) printf("%-15s %s %s\n", c->name,
				    set ? "enable" : "disable", c->help);
			else
				(void) printf("\n");
		}
	}
}

#define	GETTOGGLE(name) (struct togglelist *) \
		genget(name, (char **)Togglelist, sizeof (struct togglelist))

static int
toggle(argc, argv)
	int  argc;
	char *argv[];
{
	int retval = 1;
	char *name;
	struct togglelist *c;

	if (argc < 2) {
		(void) fprintf(stderr,
		    "Need an argument to 'toggle' command.  "
		    "'toggle ?' for help.\n");
		return (0);
	}
	argc--;
	argv++;
	while (argc--) {
		name = *argv++;
		c = GETTOGGLE(name);
		if (Ambiguous(c)) {
			(void) fprintf(stderr, "'%s': ambiguous argument "
			    "('toggle ?' for help).\n", name);
			return (0);
		} else if (c == 0) {
			(void) fprintf(stderr, "'%s': unknown argument "
			    "('toggle ?' for help).\n", name);
			return (0);
		} else {
			if (c->variable) {
				*c->variable = !*c->variable;	/* invert it */
				if (c->actionexplanation) {
			(void) printf("%s %s.\n",
				*c->variable ? "Will" : "Won't",
							c->actionexplanation);
				}
			}
			if (c->handler) {
				retval &= (*c->handler)(-1);
			}
		}
	}
	return (retval);
}

/*
 * The following perform the "set" command.
 */

#ifdef	USE_TERMIO
struct termio new_tc = { 0 };
#endif

struct setlist {
	char *name;		/* name */
	char *help;		/* help information */
	void (*handler)();
	cc_t *charp;		/* where it is located at */
};

static struct setlist Setlist[] = {
#ifdef	KLUDGELINEMODE
	{ "echo",  "character to toggle local echoing on/off", 0, &echoc },
#endif
	{ "escape", "character to escape back to telnet command mode", 0,
	    &escape },
	{ "rlogin", "rlogin escape character", 0, &rlogin },
	{ "tracefile", "file to write trace information to", SetNetTrace,
	    (cc_t *)NetTraceFile},
	{ " ", "" },
	{ " ", "The following need 'localchars' to be toggled true", 0, 0 },
	{ "flushoutput", "character to cause an Abort Output", 0,
	    termFlushCharp },
	{ "interrupt", "character to cause an Interrupt Process", 0,
	    termIntCharp },
	{ "quit", "character to cause an Abort process", 0, termQuitCharp },
	{ "eof", "character to cause an EOF ", 0, termEofCharp },
	{ " ", "" },
	{ " ", "The following are for local editing in linemode", 0, 0 },
	{ "erase", "character to use to erase a character", 0, termEraseCharp },
	{ "kill", "character to use to erase a line", 0, termKillCharp },
	{ "lnext", "character to use for literal next", 0,
	    termLiteralNextCharp },
	{ "susp", "character to cause a Suspend Process", 0, termSuspCharp },
	{ "reprint", "character to use for line reprint", 0, termRprntCharp },
	{ "worderase", "character to use to erase a word", 0, termWerasCharp },
	{ "start",	"character to use for XON", 0, termStartCharp },
	{ "stop",	"character to use for XOFF", 0, termStopCharp },
	{ "forw1",	"alternate end of line character", 0, termForw1Charp },
	{ "forw2",	"alternate end of line character", 0, termForw2Charp },
	{ "ayt",	"alternate AYT character", 0, termAytCharp },
	{ 0 }
};

static struct setlist *
getset(name)
    char *name;
{
	return ((struct setlist *)
	    genget(name, (char **)Setlist, sizeof (struct setlist)));
}

    void
set_escape_char(s)
    char *s;
{
	if (rlogin != _POSIX_VDISABLE) {
		rlogin = (s && *s) ? special(s) : _POSIX_VDISABLE;
		(void) printf("Telnet rlogin escape character is '%s'.\n",
					control(rlogin));
	} else {
		escape = (s && *s) ? special(s) : _POSIX_VDISABLE;
		(void) printf("Telnet escape character is '%s'.\n",
		    esc_control(escape));
	}
}

static int
setcmd(argc, argv)
	int  argc;
	char *argv[];
{
	int value;
	struct setlist *ct;
	struct togglelist *c;

	if (argc < 2 || argc > 3) {
		(void) printf(
			"Format is 'set Name Value'\n'set ?' for help.\n");
		return (0);
	}
	if ((argc == 2) &&
	    (isprefix(argv[1], "?") || isprefix(argv[1], "help"))) {
		for (ct = Setlist; ct->name; ct++)
			(void) printf("%-15s %s\n", ct->name, ct->help);
		(void) printf("\n");
		settogglehelp(1);
		(void) printf("%-15s %s\n", "?", "display help information");
		return (0);
	}

	ct = getset(argv[1]);
	if (ct == 0) {
		c = GETTOGGLE(argv[1]);
		if (c == 0) {
			(void) fprintf(stderr, "'%s': unknown argument "
			    "('set ?' for help).\n", argv[1]);
			return (0);
		} else if (Ambiguous(c)) {
			(void) fprintf(stderr, "'%s': ambiguous argument "
			    "('set ?' for help).\n", argv[1]);
			return (0);
		}
		if (c->variable) {
			if ((argc == 2) || (strcmp("on", argv[2]) == 0))
				*c->variable = 1;
			else if (strcmp("off", argv[2]) == 0)
				*c->variable = 0;
			else {
				(void) printf(
				    "Format is 'set togglename [on|off]'\n"
				    "'set ?' for help.\n");
				return (0);
			}
			if (c->actionexplanation) {
				(void) printf("%s %s.\n",
				    *c->variable? "Will" : "Won't",
				    c->actionexplanation);
			}
		}
		if (c->handler)
			(*c->handler)(1);
	} else if (argc != 3) {
		(void) printf(
			"Format is 'set Name Value'\n'set ?' for help.\n");
		return (0);
	} else if (Ambiguous(ct)) {
		(void) fprintf(stderr,
		    "'%s': ambiguous argument ('set ?' for help).\n", argv[1]);
		return (0);
	} else if (ct->handler) {
		(*ct->handler)(argv[2]);
		(void) printf(
		    "%s set to \"%s\".\n", ct->name, (char *)ct->charp);
	} else {
		if (strcmp("off", argv[2])) {
			value = special(argv[2]);
		} else {
			value = _POSIX_VDISABLE;
		}
		*(ct->charp) = (cc_t)value;
		(void) printf("%s character is '%s'.\n", ct->name,
		    control(*(ct->charp)));
	}
	slc_check();
	return (1);
}

static int
unsetcmd(argc, argv)
	int  argc;
	char *argv[];
{
	struct setlist *ct;
	struct togglelist *c;
	register char *name;

	if (argc < 2) {
		(void) fprintf(stderr, "Need an argument to 'unset' command.  "
		    "'unset ?' for help.\n");
		return (0);
	}
	if (isprefix(argv[1], "?") || isprefix(argv[1], "help")) {
		for (ct = Setlist; ct->name; ct++)
			(void) printf("%-15s %s\n", ct->name, ct->help);
		(void) printf("\n");
		settogglehelp(0);
		(void) printf("%-15s %s\n", "?", "display help information");
		return (0);
	}

	argc--;
	argv++;
	while (argc--) {
		name = *argv++;
		ct = getset(name);
		if (ct == 0) {
			c = GETTOGGLE(name);
			if (c == 0) {
				(void) fprintf(stderr, "'%s': unknown argument "
				    "('unset ?' for help).\n", name);
				return (0);
			} else if (Ambiguous(c)) {
				(void) fprintf(stderr,
				    "'%s': ambiguous argument "
				    "('unset ?' for help).\n", name);
				return (0);
			}
			if (c->variable) {
				*c->variable = 0;
				if (c->actionexplanation) {
					(void) printf("%s %s.\n",
					    *c->variable? "Will" : "Won't",
					    c->actionexplanation);
				}
			}
			if (c->handler)
				(*c->handler)(0);
		} else if (Ambiguous(ct)) {
			(void) fprintf(stderr, "'%s': ambiguous argument "
			    "('unset ?' for help).\n", name);
			return (0);
		} else if (ct->handler) {
			(*ct->handler)(0);
			(void) printf("%s reset to \"%s\".\n", ct->name,
			    (char *)ct->charp);
		} else {
			*(ct->charp) = _POSIX_VDISABLE;
			(void) printf("%s character is '%s'.\n", ct->name,
			    control(*(ct->charp)));
		}
	}
	return (1);
}

/*
 * The following are the data structures and routines for the
 * 'mode' command.
 */
extern int reqd_linemode;

#ifdef	KLUDGELINEMODE
extern int kludgelinemode;

static int