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/* $OpenBSD: print-cdp.c,v 1.8 2019/09/11 15:20:30 martijn Exp $ */
/*
* 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
*/
#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 */
int cdp_print_addr(const u_char * p, int l);
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, int i)
{
int type, len;
/* Cisco Discovery Protocol */
if (caplen < i + 4) {
printf("[|cdp]");
return;
}
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(" %02x/%02x", type, len);
if (len < 4)
goto error;
if (i+len > caplen) {
printf("[|cdp]");
return;
}
/* http://www.cisco.com/c/en/us/support/docs/switches/catalyst-4500-series-switches/13414-103.html#cdp */
switch(type) {
case 0x01:
printf(" DevID '%.*s'", len - 4, p + i + 4);
break;
case 0x02:
printf(" Addr");
if (cdp_print_addr(p + i + 4, len - 4))
goto error;
break;
case 0x03:
printf(" PortID '%.*s'", len - 4, p + i + 4);
break;
case 0x04:
if (len < 8)
goto error;
printf(" CAP 0x%02x", (unsigned) p[i+7]);
break;
case 0x05:
if (vflag)
printf(" Version %.*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:
printf(" VTP-Management-Domain '%.*s'", len-4, p+i+4 );
break;
case 0x0a:
if (len < 6)
goto error;
printf(" Native-VLAN-ID %d", (p[i+4]<<8) + p[i+4+1]);
break;
case 0x0b:
if (len < 5)
goto error;
printf(" Duplex %s", p[i+4] ? "full": "half" );
break;
default:
printf(" unknown-type %02x len %d", type, len );
}
/* avoid infinite loop */
if (len == 0)
break;
i += len;
}
error:
printf("[!cdp]");
}
#define CDP_CHECK_ACCESS(p, s) if ((endp - (p)) < (s)) return 1
int
cdp_print_addr(const u_char * p, int l)
{
int pl, pt, al, num;
const u_char * endp = p+l;
CDP_CHECK_ACCESS(p, 4);
num = (p[0] << 24) + (p[1]<<16) + (p[2]<<8)+ p[3];
p+=4;
printf(" (%d): ", num);
while(p < endp && num >= 0) {
CDP_CHECK_ACCESS(p, 2);
pt=*p;
pl=*(p+1);
p+=2;
CDP_CHECK_ACCESS(p, 3);
/* special case: IPv4, protocol type=0xcc, addr. length=4 */
if (pl == 1 && *p == 0xcc && p[1] == 0 && p[2] == 4) {
p+=3;
CDP_CHECK_ACCESS(p, 4);
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=", pt, pl);
CDP_CHECK_ACCESS(p, pl);
while(pl-- > 0)
printf(" %02x", *p++);
CDP_CHECK_ACCESS(p, 2);
al=(*p << 8) + *(p+1);
printf(", al=%d, a=", al);
p+=2;
CDP_CHECK_ACCESS(p, al);
while(al-- > 0)
printf(" %02x", *p++);
}
printf(" ");
num--;
}
return 0;
}
void
cdp_print_prefixes(const u_char * p, int l)
{
printf(" IPv4 Prefixes (%d):", l/5);
while (l > 0) {
if (l >= 5)
printf(" %d.%d.%d.%d/%d", p[0], p[1], p[2], p[3], p[4] );
l-=5; p+=5;
}
}
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