summaryrefslogtreecommitdiff
path: root/usr.sbin/tcpdump/print-cdp.c
blob: d5d7979b89a7713a006507a0af7d386be66bf3ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
/*	$Id	*/

/*
 * Copyright (c) 1992, 1993, 1994, 1995, 1996, 1997
 *	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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Code by Gert Doering, SpaceNet GmbH, gert@space.net
 *
 * Reference documentation:
 *    http://www.cisco.com/univercd/cc/td/doc/product/lan/trsrb/frames.htm
 */

#ifndef lint
static const char rcsid[] =
    "@(#) $Header: /cvs/OpenBSD/src/usr.sbin/tcpdump/print-cdp.c,v 1.1 2001/04/08 22:45:53 jakob Exp $";
#endif

#include <sys/param.h>
#include <sys/time.h>

#include <netinet/in.h>

#include <ctype.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>

#include "interface.h"
#include "addrtoname.h"
#include "extract.h"			/* must come after interface.h */

static void cdp_print_addr( const u_char * p, int l );
static void cdp_print_prefixes( const u_char * p, int l );

/*
 * Returns non-zero IFF it succeeds in printing the header
 */
void
cdp_print(const u_char *p, u_int length, u_int caplen,
	  const u_char *esrc, const u_char *edst)
{
	int i;
	int type, len;

	/* Cisco Discovery Protocol */


	if ( caplen < 12 ) {
		(void)printf("[|cdp]");
		return;
	}

	i=8;		/* CDP data starts at offset 8 */
	printf ("CDP v%d, ttl=%ds", p[i], p[i+1] );
	i+=4;		/* skip version, TTL and chksum */

	while (i < length) {
	    if ( i+4 > caplen ) {
		printf("[!cdp]");
		return;
	    }
	    type = (p[i]<<8) + p[i+1];
	    len  = (p[i+2]<<8) + p[i+3];

	    if ( vflag )
		printf( "\n\t%02x/%02x", type, len );
	    else
		printf( "\n\t" );

	    if ( i+len > caplen ) {
		printf("[!cdp]");
		return;
	    }

	    switch( type )
	    {
	    case 0x01:
		printf( " DevID '%.*s'", len-4, p+i+4 );
		break;
	    case 0x02:
		printf( " Addr" );
		cdp_print_addr( p+i+4, len-4 );
		break;
	    case 0x03:
		printf( " PortID '%.*s'", len-4, p+i+4 );
		break;
	    case 0x04:
		printf( " CAP 0x%02x", (unsigned) p[i+7] );
		break;
	    case 0x05:
		if ( vflag )
		    printf( " Version:\n%.*s", len-4, p+i+4 );
		else
		    printf( " Version: (suppressed)" );
		break;
	    case 0x06:
		printf( " Platform: '%.*s'", len-4, p+i+4 );
		break;
	    case 0x07:
	        cdp_print_prefixes( p+i+4, len-4 );
		break;
	    case 0x09:		/* guess - not documented */
		printf( " VTP Management Domain: '%.*s'", len-4, p+i+4 );
		break;
	    case 0x0a:		/* guess - not documented */
		printf( " Native VLAN ID: %d", (p[i+4]<<8) + p[i+4+1] - 1 );
		break;
	    case 0x0b:		/* guess - not documented */
		printf( " Duplex: %s", p[i+4] ? "full": "half" );
		break;
	    default:
		printf( " unknown field type %02x, len %d", type, len );
	    }

	    /* avoid infinite loop */
	    if (len == 0)
		break;
	    i+=len;
	}
}

static void
cdp_print_addr( const u_char * p, int l )
{
	int pl, al, num;
	const u_char * endp = p+l;

	num = (p[0] << 24) + (p[1]<<16) + (p[2]<<8)+ p[3];
	p+=4;

	printf(" (%d): ", num );

	while( p < endp && num >= 0) {
		pl=*(p+1);
		p+=2; 

		/* special case: IPv4, protocol type=0xcc, addr. length=4 */
		if ( pl == 1 && *p == 0xcc && 
		     p[1] == 0 && p[2] == 4 ) {
			p+=3;

			printf( "IPv4 %d.%d.%d.%d ", p[0], p[1], p[2], p[3] );
			p+=4;
		} else {	/* generic case: just print raw data */
			printf("pt=0x%02x, pl=%d, pb=", *(p-2), pl);
			while( pl-- > 0 )
				printf( " %02x", *p++);
			al=(*p << 8) + *(p+1);
			printf( ", al=%d, a=", al );
			p+=2; 
			while( al-- > 0 )
				printf( " %02x", *p++);
		}
		printf("  ");
		num--;
	}
}


static void
cdp_print_prefixes( const u_char * p, int l )
{
    printf( " IPv4 Prefixes (%d):", l/5 );

    while(l > 0) {
	printf( " %d.%d.%d.%d/%d", p[0], p[1], p[2], p[3], p[4] );
	l-=5; p+=5;
    }
}