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   1 /*
   2  * Copyright (c) 1996, 1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  *
  21  * Initial contribution from Francis Dupont (francis.dupont@inria.fr)
  22  */
  23
  24 /* \summary: Interior Gateway Routing Protocol (IGRP) printer */
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include <config.h>
  28 #endif
  29
  30 #include "netdissect-stdinc.h"
  31
  32 #include "netdissect.h"
  33 #include "extract.h"
  34
  35 /* Cisco IGRP definitions */
  36
  37 /* IGRP Header */
  38
  39 struct igrphdr {
  40         nd_uint8_t ig_vop;      /* protocol version number / opcode */
  41 #define IGRP_V(x)       (((x) & 0xf0) >> 4)
  42 #define IGRP_OP(x)      ((x) & 0x0f)
  43         nd_uint8_t ig_ed;       /* edition number */
  44         nd_uint16_t ig_as;      /* autonomous system number */
  45         nd_uint16_t ig_ni;      /* number of subnet in local net */
  46         nd_uint16_t ig_ns;      /* number of networks in AS */
  47         nd_uint16_t ig_nx;      /* number of networks ouside AS */
  48         nd_uint16_t ig_sum;     /* checksum of IGRP header & data */
  49 };
  50
  51 #define IGRP_UPDATE     1
  52 #define IGRP_REQUEST    2
  53
  54 /* IGRP routing entry */
  55
  56 struct igrprte {
  57         nd_byte igr_net[3];     /* 3 significant octets of IP address */
  58         nd_uint24_t igr_dly;    /* delay in tens of microseconds */
  59         nd_uint24_t igr_bw;     /* bandwidth in units of 1 kb/s */
  60         nd_uint16_t igr_mtu;    /* MTU in octets */
  61         nd_uint8_t igr_rel;     /* percent packets successfully tx/rx */
  62         nd_uint8_t igr_ld;      /* percent of channel occupied */
  63         nd_uint8_t igr_hct;     /* hop count */
  64 };
  65
  66 #define IGRP_RTE_SIZE   14      /* don't believe sizeof ! */
  67
  68 static void
  69 igrp_entry_print(netdissect_options *ndo, const struct igrprte *igr,
  70     int is_interior, int is_exterior)
  71 {
  72         u_int delay, bandwidth;
  73         u_int metric, mtu;
  74
  75         if (is_interior)
  76                 ND_PRINT(" *.%u.%u.%u", igr->igr_net[0],
  77                     igr->igr_net[1], igr->igr_net[2]);
  78         else if (is_exterior)
  79                 ND_PRINT(" X%u.%u.%u.0", igr->igr_net[0],
  80                     igr->igr_net[1], igr->igr_net[2]);
  81         else
  82                 ND_PRINT(" %u.%u.%u.0", igr->igr_net[0],
  83                     igr->igr_net[1], igr->igr_net[2]);
  84
  85         delay = GET_BE_U_3(igr->igr_dly);
  86         bandwidth = GET_BE_U_3(igr->igr_bw);
  87         metric = bandwidth + delay;
  88         if (metric > 0xffffff)
  89                 metric = 0xffffff;
  90         mtu = GET_BE_U_2(igr->igr_mtu);
  91
  92         ND_PRINT(" d=%u b=%u r=%u l=%u M=%u mtu=%u in %u hops",
  93             10 * delay, bandwidth == 0 ? 0 : 10000000 / bandwidth,
  94             GET_U_1(igr->igr_rel), GET_U_1(igr->igr_ld), metric,
  95             mtu, GET_U_1(igr->igr_hct));
  96 }
  97
  98 static const struct tok op2str[] = {
  99         { IGRP_UPDATE,          "update" },
 100         { IGRP_REQUEST,         "request" },
 101         { 0,                    NULL }
 102 };
 103
 104 void
 105 igrp_print(netdissect_options *ndo, const u_char *bp, u_int length)
 106 {
 107         const struct igrphdr *hdr;
 108         const u_char *cp;
 109         u_int nint, nsys, next;
 110
 111         ndo->ndo_protocol = "igrp";
 112         hdr = (const struct igrphdr *)bp;
 113         cp = (const u_char *)(hdr + 1);
 114         ND_PRINT("igrp:");
 115
 116         /* Header */
 117         ND_TCHECK_SIZE(hdr);
 118         nint = GET_BE_U_2(hdr->ig_ni);
 119         nsys = GET_BE_U_2(hdr->ig_ns);
 120         next = GET_BE_U_2(hdr->ig_nx);
 121
 122         ND_PRINT(" %s V%u edit=%u AS=%u (%u/%u/%u)",
 123             tok2str(op2str, "op-#%u", IGRP_OP(GET_U_1(hdr->ig_vop))),
 124             IGRP_V(GET_U_1(hdr->ig_vop)),
 125             GET_U_1(hdr->ig_ed),
 126             GET_BE_U_2(hdr->ig_as),
 127             nint,
 128             nsys,
 129             next);
 130
 131         length -= sizeof(*hdr);
 132         while (length >= IGRP_RTE_SIZE) {
 133                 if (nint > 0) {
 134                         ND_TCHECK_LEN(cp, IGRP_RTE_SIZE);
 135                         igrp_entry_print(ndo, (const struct igrprte *)cp, 1, 0);
 136                         --nint;
 137                 } else if (nsys > 0) {
 138                         ND_TCHECK_LEN(cp, IGRP_RTE_SIZE);
 139                         igrp_entry_print(ndo, (const struct igrprte *)cp, 0, 0);
 140                         --nsys;
 141                 } else if (next > 0) {
 142                         ND_TCHECK_LEN(cp, IGRP_RTE_SIZE);
 143                         igrp_entry_print(ndo, (const struct igrprte *)cp, 0, 1);
 144                         --next;
 145                 } else {
 146                         ND_PRINT(" [extra bytes %u]", length);
 147                         break;
 148                 }
 149                 cp += IGRP_RTE_SIZE;
 150                 length -= IGRP_RTE_SIZE;
 151         }
 152         if (nint == 0 && nsys == 0 && next == 0)
 153                 return;
 154 trunc:
 155         nd_print_trunc(ndo);
 156 }