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
39struct 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 outside 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
56struct 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
68static void
69igrp_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
85static const struct tok op2str[] = {
86	{ IGRP_UPDATE,		"update" },
87	{ IGRP_REQUEST,		"request" },
88	{ 0,			NULL }
89};
90
91void
92igrp_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