/*	$NetBSD: print-telnet.c,v 1.2 1999/10/11 12:40:12 sjg Exp $ 	*//*- * Copyright (c) 1997, 1998 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Simon J. Gerraty. * * 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 NetBSD *        Foundation, Inc. and its contributors. * 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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 (c) 1994, Simon J. Gerraty. * *      This is free software.  It comes with NO WARRANTY. *      Permission to use, modify and distribute this source code *      is granted subject to the following conditions. *      1/ that the above copyright notice and this notice *      are preserved in all copies. */#ifdef HAVE_CONFIG_H#include "config.h"#endif#ifndef lintstatic const char rcsid[] _U_ =     "@(#) $Header: /tcpdump/master/tcpdump/print-telnet.c,v 1.24 2003-12-29 11:05:10 hannes Exp $";#endif#include <tcpdump-stdinc.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#include "interface.h"#include "addrtoname.h"#define TELCMDS#define TELOPTS#include "telnet.h"/* normal */static const char *cmds[] = {	"IS", "SEND", "INFO",};/* 37: Authentication */static const char *authcmd[] = {	"IS", "SEND", "REPLY", "NAME",};static const char *authtype[] = {	"NULL", "KERBEROS_V4", "KERBEROS_V5", "SPX", "MINK",	"SRP", "RSA", "SSL", NULL, NULL,	"LOKI", "SSA", "KEA_SJ", "KEA_SJ_INTEG", "DSS",	"NTLM",};/* 38: Encryption */static const char *enccmd[] = {	"IS", "SUPPORT", "REPLY", "START", "END",	"REQUEST-START", "REQUEST-END", "END_KEYID", "DEC_KEYID",};static const char *enctype[] = {	"NULL", "DES_CFB64", "DES_OFB64", "DES3_CFB64", "DES3_OFB64",	NULL, "CAST5_40_CFB64", "CAST5_40_OFB64", "CAST128_CFB64", "CAST128_OFB64",};#define STR_OR_ID(x, tab) \	(((x) < sizeof(tab)/sizeof(tab[0]) && tab[(x)]) ? tab[(x)] : numstr(x))static char *numstr(int x){	static char buf[20];	snprintf(buf, sizeof(buf), "%#x", x);	return buf;}/* sp points to IAC byte */static inttelnet_parse(const u_char *sp, u_int length, int print){	int i, x;	u_int c;	const u_char *osp, *p;#define FETCH(c, sp, length) \	do { \		if (length < 1) \			goto pktend; \		TCHECK(*sp); \		c = *sp++; \		length--; \	} while (0)	osp = sp;	FETCH(c, sp, length);	if (c != IAC)		goto pktend;	FETCH(c, sp, length);	if (c == IAC) {		/* <IAC><IAC>! */		if (print)			printf("IAC IAC");		goto done;	}	i = c - TELCMD_FIRST;	if (i < 0 || i > IAC - TELCMD_FIRST)		goto pktend;	switch (c) {	case DONT:	case DO:	case WONT:	case WILL:	case SB:		/* DONT/DO/WONT/WILL x */		FETCH(x, sp, length);		if (x >= 0 && x < NTELOPTS) {			if (print)				(void)printf("%s %s", telcmds[i], telopts[x]);		} else {			if (print)				(void)printf("%s %#x", telcmds[i], x);		}		if (c != SB)			break;		/* IAC SB .... IAC SE */		p = sp;		while (length > (u_int)(p + 1 - sp)) {			if (p[0] == IAC && p[1] == SE)				break;			p++;		}		if (*p != IAC)			goto pktend;		switch (x) {		case TELOPT_AUTHENTICATION:			if (p <= sp)				break;			FETCH(c, sp, length);			if (print)				(void)printf(" %s", STR_OR_ID(c, authcmd));			if (p <= sp)				break;			FETCH(c, sp, length);			if (print)				(void)printf(" %s", STR_OR_ID(c, authtype));			break;		case TELOPT_ENCRYPT:			if (p <= sp)				break;			FETCH(c, sp, length);			if (print)				(void)printf(" %s", STR_OR_ID(c, enccmd));			if (p <= sp)				break;			FETCH(c, sp, length);			if (print)				(void)printf(" %s", STR_OR_ID(c, enctype));			break;		default:			if (p <= sp)				break;			FETCH(c, sp, length);			if (print)				(void)printf(" %s", STR_OR_ID(c, cmds));			break;		}		while (p > sp) {			FETCH(x, sp, length);			if (print)				(void)printf(" %#x", x);		}		/* terminating IAC SE */		if (print)			(void)printf(" SE");		sp += 2;		length -= 2;		break;	default:		if (print)			(void)printf("%s", telcmds[i]);		goto done;	}done:	return sp - osp;trunc:	(void)printf("[|telnet]");pktend:	return -1;#undef FETCH}voidtelnet_print(const u_char *sp, u_int length){	int first = 1;	const u_char *osp;	int l;	osp = sp;	while (length > 0 && *sp == IAC) {		l = telnet_parse(sp, length, 0);		if (l < 0)			break;		/*		 * now print it		 */		if (Xflag && 2 < vflag) {			if (first)				printf("\nTelnet:");			hex_print_with_offset("\n", sp, l, sp - osp);			if (l > 8)				printf("\n\t\t\t\t");			else				printf("%*s\t", (8 - l) * 3, "");		} else			printf("%s", (first) ? " [telnet " : ", ");		(void)telnet_parse(sp, length, 1);		first = 0;		sp += l;		length -= l;	}	if (!first) {		if (Xflag && 2 < vflag)			printf("\n");		else			printf("]");	}}