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 /* sizeof() is accurate now */
67
68 static void
igrp_entry_print(netdissect_options * ndo,const struct igrprte * igr)69 igrp_entry_print(netdissect_options *ndo, const struct igrprte *igr)
70 {
71 u_int delay, bandwidth;
72 u_int metric, mtu;
73
74 delay = GET_BE_U_3(igr->igr_dly);
75 bandwidth = GET_BE_U_3(igr->igr_bw);
76 metric = ND_MIN(bandwidth + delay, 0xffffff);
77 mtu = GET_BE_U_2(igr->igr_mtu);
78
79 ND_PRINT(" d=%u b=%u r=%u l=%u M=%u mtu=%u in %u hops",
80 10 * delay, bandwidth == 0 ? 0 : 10000000 / bandwidth,
81 GET_U_1(igr->igr_rel), GET_U_1(igr->igr_ld), metric,
82 mtu, GET_U_1(igr->igr_hct));
83 }
84
85 static const struct tok op2str[] = {
86 { IGRP_UPDATE, "update" },
87 { IGRP_REQUEST, "request" },
88 { 0, NULL }
89 };
90
91 void
igrp_print(netdissect_options * ndo,const u_char * bp,u_int length)92 igrp_print(netdissect_options *ndo, const u_char *bp, u_int length)
93 {
94 const struct igrphdr *hdr;
95 const u_char *cp;
96 u_int nint, nsys, next;
97 uint16_t cksum;
98
99 ndo->ndo_protocol = "igrp";
100 hdr = (const struct igrphdr *)bp;
101 cp = (const u_char *)(hdr + 1);
102 ND_PRINT("igrp:");
103
104 /* Header */
105 nint = GET_BE_U_2(hdr->ig_ni);
106 nsys = GET_BE_U_2(hdr->ig_ns);
107 next = GET_BE_U_2(hdr->ig_nx);
108
109 ND_PRINT(" %s V%u edit=%u AS=%u (%u/%u/%u)",
110 tok2str(op2str, "op-#%u", IGRP_OP(GET_U_1(hdr->ig_vop))),
111 IGRP_V(GET_U_1(hdr->ig_vop)),
112 GET_U_1(hdr->ig_ed),
113 GET_BE_U_2(hdr->ig_as),
114 nint,
115 nsys,
116 next);
117 cksum = GET_BE_U_2(hdr->ig_sum);
118 if (ndo->ndo_vflag)
119 ND_PRINT(" checksum=0x%04x", cksum);
120
121 length -= sizeof(*hdr);
122 while (length >= IGRP_RTE_SIZE) {
123 const struct igrprte *igr = (const struct igrprte *)cp;
124 uint8_t net0 = GET_U_1(&igr->igr_net[0]);
125 uint8_t net1 = GET_U_1(&igr->igr_net[1]);
126 uint8_t net2 = GET_U_1(&igr->igr_net[2]);
127
128 if (nint > 0) {
129 ND_PRINT(" *.%u.%u.%u", net0, net1, net2);
130 igrp_entry_print(ndo, igr);
131 --nint;
132 } else if (nsys > 0) {
133 ND_PRINT(" %u.%u.%u.0", net0, net1, net2);
134 igrp_entry_print(ndo, igr);
135 --nsys;
136 } else if (next > 0) {
137 ND_PRINT(" X%u.%u.%u.0", net0, net1, net2);
138 igrp_entry_print(ndo, igr);
139 --next;
140 } else {
141 ND_PRINT(" [extra bytes %u]", length);
142 break;
143 }
144 cp += IGRP_RTE_SIZE;
145 length -= IGRP_RTE_SIZE;
146 }
147 if (nint || nsys || next || length)
148 nd_print_invalid(ndo);
149 }
150