/* $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 lint
static 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 int
telnet_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
}
void
telnet_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("]");
}
}