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

   1 /*
   2  * Copyright (c) 1998-2004  Hannes Gredler <hannes@tcpdump.org>
   3  *      The TCPDUMP project
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code
   7  * distributions retain the above copyright notice and this paragraph
   8  * in its entirety, and (2) distributions including binary code include
   9  * the above copyright notice and this paragraph in its entirety in
  10  * the documentation or other materials provided with the distribution.
  11  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  12  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  13  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  14  * FOR A PARTICULAR PURPOSE.
  15  */
  16
  17 #ifndef lint
  18 static const char rcsid[] _U_ =
  19     "@(#) $Header: /tcpdump/master/tcpdump/print-eigrp.c,v 1.1 2004-04-30 22:22:04 hannes Exp $";
  20 #endif
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <tcpdump-stdinc.h>
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31
  32 #include "interface.h"
  33 #include "extract.h"
  34 #include "addrtoname.h"
  35
  36 /*
  37  * packet format documented at
  38  * http://www.rhyshaden.com/eigrp.htm
  39  */
  40
  41 struct eigrp_common_header {
  42     u_int8_t version;
  43     u_int8_t opcode;
  44     u_int8_t checksum[2];
  45     u_int8_t flags[4];
  46     u_int8_t seq[4];
  47     u_int8_t ack[4];
  48     u_int8_t asn[4];
  49 };
  50
  51 #define EIGRP_VERSION                        2
  52
  53 #define EIGRP_OPCODE_UPDATE                  1
  54 #define EIGRP_OPCODE_QUERY                   3
  55 #define EIGRP_OPCODE_REPLY                   4
  56 #define EIGRP_OPCODE_HELLO                   5
  57 #define EIGRP_OPCODE_IPXSAP                  6
  58 #define EIGRP_OPCODE_PROBE                   7
  59
  60 static const struct tok eigrp_opcode_values[] = {
  61     { EIGRP_OPCODE_UPDATE, "Update" },
  62     { EIGRP_OPCODE_QUERY, "Query" },
  63     { EIGRP_OPCODE_REPLY, "Reply" },
  64     { EIGRP_OPCODE_HELLO, "Hello" },
  65     { EIGRP_OPCODE_IPXSAP, "IPX SAP" },
  66     { EIGRP_OPCODE_PROBE, "Probe" },
  67     { 0, NULL}
  68 };
  69
  70 struct eigrp_tlv_header {
  71     u_int8_t type[2];
  72     u_int8_t length[2];
  73 };
  74
  75 #define EIGRP_TLV_GENERAL_PARM   0x0001
  76 #define EIGRP_TLV_SEQ            0x0003
  77 #define EIGRP_TLV_SW_VERSION     0x0004
  78 #define EIGRP_TLV_MCAST_SEQ      0x0005
  79 #define EIGRP_TLV_IP_INT         0x0102
  80 #define EIGRP_TLV_IP_EXT         0x0103
  81 #define EIGRP_TLV_AT_INT         0x0202
  82 #define EIGRP_TLV_AT_EXT         0x0203
  83 #define EIGRP_TLV_AT_CABLE_SETUP 0x0204
  84 #define EIGRP_TLV_IPX_INT        0x0302
  85 #define EIGRP_TLV_IPX_EXT        0x0303
  86
  87 static const struct tok eigrp_tlv_values[] = {
  88     { EIGRP_TLV_GENERAL_PARM, "General Parameters"},
  89     { EIGRP_TLV_SEQ, "Sequence"},
  90     { EIGRP_TLV_SW_VERSION, "Software Version"},
  91     { EIGRP_TLV_MCAST_SEQ, "Next Multicast Sequence"},
  92     { EIGRP_TLV_IP_INT, "IP Internal routes"},
  93     { EIGRP_TLV_IP_EXT, "IP External routes"},
  94     { EIGRP_TLV_AT_INT, "AppleTalk Internal routes"},
  95     { EIGRP_TLV_AT_EXT, "AppleTalk External routes"},
  96     { EIGRP_TLV_AT_CABLE_SETUP, "AppleTalk Cable setup"},
  97     { EIGRP_TLV_IPX_INT, "IPX Internal routes"},
  98     { EIGRP_TLV_IPX_EXT, "IPX External routes"},
  99     { 0, NULL}
 100 };
 101
 102 void
 103 eigrp_print(register const u_char *pptr, register u_int len) {
 104
 105     const struct eigrp_common_header *eigrp_com_header;
 106     const struct eigrp_tlv_header *eigrp_tlv_header;
 107     const u_char *tptr,*obj_tptr;
 108     int tlen,eigrp_tlv_len,eigrp_tlv_type,obj_tlen;
 109
 110     tptr=pptr;
 111     eigrp_com_header = (const struct eigrp_common_header *)pptr;
 112     TCHECK(*eigrp_com_header);
 113
 114     /*
 115      * Sanity checking of the header.
 116      */
 117     if (eigrp_com_header->version != EIGRP_VERSION) {
 118         printf("EIGRP version %u packet not supported",eigrp_com_header->version);
 119         return;
 120     }
 121
 122     /* in non-verbose mode just lets print the basic Message Type*/
 123     if (vflag < 1) {
 124         printf("EIGRP %s, length: %u",
 125                tok2str(eigrp_opcode_values, "unknown (%u)",eigrp_com_header->opcode),
 126                len);
 127         return;
 128     }
 129
 130     /* ok they seem to want to know everything - lets fully decode it */
 131
 132     tlen=len-sizeof(struct eigrp_common_header);
 133
 134     /* FIXME print other header info */
 135     printf("\n\tEIGRP v%u, opcode: %s (%u), chksum: 0x%04x, Flags: [0x%08x]\n\tseq: 0x%08x, ack: 0x%08x, AS: %u, length: %u",
 136            eigrp_com_header->version,
 137            tok2str(eigrp_opcode_values, "unknown, type: %u",eigrp_com_header->opcode),
 138            eigrp_com_header->opcode,
 139            EXTRACT_16BITS(&eigrp_com_header->checksum),
 140            EXTRACT_32BITS(&eigrp_com_header->flags),
 141            EXTRACT_32BITS(&eigrp_com_header->seq),
 142            EXTRACT_32BITS(&eigrp_com_header->ack),
 143            EXTRACT_32BITS(&eigrp_com_header->asn),
 144            tlen);
 145
 146     tptr+=sizeof(const struct eigrp_common_header);
 147
 148     while(tlen>0) {
 149         /* did we capture enough for fully decoding the object header ? */
 150         if (!TTEST2(*tptr, sizeof(struct eigrp_tlv_header)))
 151             goto trunc;
 152
 153         eigrp_tlv_header = (const struct eigrp_tlv_header *)tptr;
 154         eigrp_tlv_len=EXTRACT_16BITS(&eigrp_tlv_header->length);
 155         eigrp_tlv_type=EXTRACT_16BITS(&eigrp_tlv_header->type);
 156
 157
 158         if (eigrp_tlv_len == 0 || eigrp_tlv_len > tlen) {
 159             print_unknown_data(tptr+sizeof(sizeof(struct eigrp_tlv_header)),"\n\t    ",tlen);
 160             return;
 161         }
 162
 163         printf("\n\t  %s TLV (0x%04x), length: %u",
 164                tok2str(eigrp_tlv_values,
 165                        "Unknown",
 166                        eigrp_tlv_type),
 167                eigrp_tlv_type,
 168                eigrp_tlv_len);
 169
 170         obj_tptr=tptr+sizeof(struct eigrp_tlv_header);
 171         obj_tlen=eigrp_tlv_len-sizeof(struct eigrp_tlv_header);
 172
 173         /* did we capture enough for fully decoding the object ? */
 174         if (!TTEST2(*tptr, eigrp_tlv_len))
 175             goto trunc;
 176
 177         switch(eigrp_tlv_type) {
 178
 179             /*
 180              * FIXME those are the defined TLVs that lack a decoder
 181              * you are welcome to contribute code ;-)
 182              */
 183
 184         case EIGRP_TLV_GENERAL_PARM:
 185         case EIGRP_TLV_SEQ:
 186         case EIGRP_TLV_SW_VERSION:
 187         case EIGRP_TLV_MCAST_SEQ:
 188         case EIGRP_TLV_IP_INT:
 189         case EIGRP_TLV_IP_EXT:
 190         case EIGRP_TLV_AT_INT:
 191         case EIGRP_TLV_AT_EXT:
 192         case EIGRP_TLV_AT_CABLE_SETUP:
 193         case EIGRP_TLV_IPX_INT:
 194         case EIGRP_TLV_IPX_EXT:
 195
 196         default:
 197             if (vflag <= 1)
 198                 print_unknown_data(obj_tptr,"\n\t    ",obj_tlen);
 199             break;
 200         }
 201         /* do we want to see an additionally hexdump ? */
 202         if (vflag > 1)
 203             print_unknown_data(tptr+sizeof(sizeof(struct eigrp_tlv_header)),"\n\t    ",
 204                                eigrp_tlv_len-sizeof(struct eigrp_tlv_header));
 205
 206         tptr+=eigrp_tlv_len;
 207         tlen-=eigrp_tlv_len;
 208     }
 209     return;
 210 trunc:
 211     printf("\n\t\t packet exceeded snapshot");
 212 }