The Tcpdump Group git mirrors - tcpdump/blob - print-lldp.c

   1 /*
   2  * Copyright (c) 1998-2007 The TCPDUMP project
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that: (1) source code
   6  * distributions retain the above copyright notice and this paragraph
   7  * in its entirety, and (2) distributions including binary code include
   8  * the above copyright notice and this paragraph in its entirety in
   9  * the documentation or other materials provided with the distribution.
  10  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  11  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  12  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  13  * FOR A PARTICULAR PURPOSE.
  14  *
  15  * support for the IEEE Link Discovery Protocol as per 802.1ab
  16  *
  17  * Original code by Hannes Gredler (hannes@juniper.net)
  18  */
  19
  20 #ifndef lint
  21 static const char rcsid[] _U_ =
  22     "@(#) $Header: /tcpdump/master/tcpdump/print-lldp.c,v 1.1 2007-08-03 11:03:19 hannes Exp $";
  23 #endif
  24
  25 #ifdef HAVE_CONFIG_H
  26 #include "config.h"
  27 #endif
  28
  29 #include <tcpdump-stdinc.h>
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34
  35 #include "interface.h"
  36 #include "extract.h"
  37 #include "addrtoname.h"
  38
  39 #define LLDP_EXTRACT_TYPE(x) (((x)&0xfe00)>>9)
  40 #define LLDP_EXTRACT_LEN(x) ((x)&0x01ff)
  41
  42 #define LLDP_END_TLV             0
  43 #define LLDP_CHASSIS_ID_TLV      1
  44 #define LLDP_PORT_ID_TLV         2
  45 #define LLDP_TTL_TLV             3
  46 #define LLDP_PORT_DESCR_TLV      4
  47 #define LLDP_SYSTEM_NAME_TLV     5
  48 #define LLDP_SYSTEM_DESCR_TLV    6
  49 #define LLDP_SYSTEM_CAP_TLV      7
  50 #define LLDP_MGMT_ADDR_TLV       8
  51 #define LLDP_PRIVATE_TLV       127
  52
  53
  54 static const struct tok lldp_tlv_values[] = {
  55     { LLDP_END_TLV, "End" },
  56     { LLDP_CHASSIS_ID_TLV, "Chassis ID" },
  57     { LLDP_PORT_ID_TLV, "Port ID" },
  58     { LLDP_TTL_TLV, "Time to Live" },
  59     { LLDP_PORT_DESCR_TLV, "Port Description" },
  60     { LLDP_SYSTEM_NAME_TLV, "System Name" },
  61     { LLDP_SYSTEM_DESCR_TLV, "System Description" },
  62     { LLDP_SYSTEM_CAP_TLV, "System Capabilities" },
  63     { LLDP_MGMT_ADDR_TLV, "Management Address" },
  64     { LLDP_PRIVATE_TLV, "Organization specific" },
  65     { 0, NULL}
  66 };
  67
  68 void lldp_print(register const u_char *pptr, register u_int len) {
  69
  70     u_int16_t tlv;
  71     u_int tlen, hexdump, tlv_type, tlv_len;
  72     const u_char *tptr;
  73
  74     tptr = pptr;
  75     tlen = len;
  76
  77     printf("LLDP, length %u", len);
  78
  79     if (!vflag) {
  80         return;
  81     }
  82
  83     while (tlen >= sizeof(tlv)) {
  84
  85         TCHECK2(*tptr, sizeof(tlv));
  86
  87         tlv = EXTRACT_16BITS(tptr);
  88
  89         tlv_type = LLDP_EXTRACT_TYPE(tlv);
  90         tlv_len = LLDP_EXTRACT_LEN(tlv);
  91         hexdump = FALSE;
  92
  93         tlen -= sizeof(tlv);
  94         tptr += sizeof(tlv);
  95
  96         printf("\n\t%s TLV (%u), length %u",
  97                tok2str(lldp_tlv_values, "Unknown", tlv_type),
  98                tlv_type, tlv_len);
  99
 100         /* infinite loop check */
 101         if (!tlv_type || !tlv_len) {
 102             break;
 103         }
 104
 105         TCHECK2(*tptr, tlv_len);
 106
 107         switch (tlv_type) {
 108         case LLDP_TTL_TLV:
 109             printf(", TTL %us", EXTRACT_16BITS(tptr));
 110             break;
 111
 112         case LLDP_SYSTEM_NAME_TLV:
 113         case LLDP_PORT_DESCR_TLV:
 114             printf(", ");
 115             safeputs((const char *)tptr, tlv_len);
 116             break;
 117
 118         case LLDP_SYSTEM_DESCR_TLV:
 119             printf("\n\t  ");
 120             safeputs((const char *)tptr, tlv_len);
 121             break;
 122
 123         default:
 124             hexdump = TRUE;
 125         }
 126
 127         /* do we also want to see a hex dump ? */
 128         if (vflag > 1 || hexdump) {
 129             print_unknown_data(tptr,"\n\t  ", tlv_len);
 130         }
 131
 132         tlen -= tlv_len;
 133         tptr += tlv_len;
 134     }
 135     return;
 136  trunc:
 137     printf("\n\t[|LLDP]");
 138 }