1/*
2 * Copyright (c) 1989, 1990, 1991, 1993, 1994, 1995, 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
22#ifndef lint
23static const char rcsid[] _U_ =
24    "@(#) $Header: /tcpdump/master/tcpdump/print-sl.c,v 1.65 2005-04-06 21:32:42 mcr Exp $ (LBL)";
25#endif
26
27#ifdef HAVE_CONFIG_H
28#include "config.h"
29#endif
30
31#include <tcpdump-stdinc.h>
32
33#include <pcap.h>
34#include <stdio.h>
35
36#include "interface.h"
37#include "addrtoname.h"
38#include "extract.h"			/* must come after interface.h */
39
40#include "ip.h"
41#include "tcp.h"
42#include "slip.h"
43#include "slcompress.h"
44
45static u_int lastlen[2][256];
46static u_int lastconn = 255;
47
48static void sliplink_print(const u_char *, const struct ip *, u_int);
49static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
50
51u_int
52sl_if_print(const struct pcap_pkthdr *h, const u_char *p)
53{
54	register u_int caplen = h->caplen;
55	register u_int length = h->len;
56	register const struct ip *ip;
57
58	if (caplen < SLIP_HDRLEN) {
59		printf("[|slip]");
60		return (caplen);
61	}
62
63	length -= SLIP_HDRLEN;
64
65	ip = (struct ip *)(p + SLIP_HDRLEN);
66
67	if (eflag)
68		sliplink_print(p, ip, length);
69
70	switch (IP_V(ip)) {
71	case 4:
72	        ip_print(gndo, (u_char *)ip, length);
73		break;
74#ifdef INET6
75	case 6:
76		ip6_print(gndo, (u_char *)ip, length);
77		break;
78#endif
79	default:
80		printf ("ip v%d", IP_V(ip));
81	}
82
83	return (SLIP_HDRLEN);
84}
85
86u_int
87sl_bsdos_if_print(const struct pcap_pkthdr *h, const u_char *p)
88{
89	register u_int caplen = h->caplen;
90	register u_int length = h->len;
91	register const struct ip *ip;
92
93	if (caplen < SLIP_HDRLEN) {
94		printf("[|slip]");
95		return (caplen);
96	}
97
98	length -= SLIP_HDRLEN;
99
100	ip = (struct ip *)(p + SLIP_HDRLEN);
101
102#ifdef notdef
103	if (eflag)
104		sliplink_print(p, ip, length);
105#endif
106
107	ip_print(gndo, (u_char *)ip, length);
108
109	return (SLIP_HDRLEN);
110}
111
112static void
113sliplink_print(register const u_char *p, register const struct ip *ip,
114	       register u_int length)
115{
116	int dir;
117	u_int hlen;
118
119	dir = p[SLX_DIR];
120	putchar(dir == SLIPDIR_IN ? 'I' : 'O');
121	putchar(' ');
122
123	if (nflag) {
124		/* XXX just dump the header */
125		register int i;
126
127		for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
128			printf("%02x.", p[i]);
129		printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
130		return;
131	}
132	switch (p[SLX_CHDR] & 0xf0) {
133
134	case TYPE_IP:
135		printf("ip %d: ", length + SLIP_HDRLEN);
136		break;
137
138	case TYPE_UNCOMPRESSED_TCP:
139		/*
140		 * The connection id is stored in the IP protocol field.
141		 * Get it from the link layer since sl_uncompress_tcp()
142		 * has restored the IP header copy to IPPROTO_TCP.
143		 */
144		lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
145		hlen = IP_HL(ip);
146		hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);
147		lastlen[dir][lastconn] = length - (hlen << 2);
148		printf("utcp %d: ", lastconn);
149		break;
150
151	default:
152		if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
153			compressed_sl_print(&p[SLX_CHDR], ip,
154			    length, dir);
155			printf(": ");
156		} else
157			printf("slip-%d!: ", p[SLX_CHDR]);
158	}
159}
160
161static const u_char *
162print_sl_change(const char *str, register const u_char *cp)
163{
164	register u_int i;
165
166	if ((i = *cp++) == 0) {
167		i = EXTRACT_16BITS(cp);
168		cp += 2;
169	}
170	printf(" %s%d", str, i);
171	return (cp);
172}
173
174static const u_char *
175print_sl_winchange(register const u_char *cp)
176{
177	register short i;
178
179	if ((i = *cp++) == 0) {
180		i = EXTRACT_16BITS(cp);
181		cp += 2;
182	}
183	if (i >= 0)
184		printf(" W+%d", i);
185	else
186		printf(" W%d", i);
187	return (cp);
188}
189
190static void
191compressed_sl_print(const u_char *chdr, const struct ip *ip,
192		    u_int length, int dir)
193{
194	register const u_char *cp = chdr;
195	register u_int flags, hlen;
196
197	flags = *cp++;
198	if (flags & NEW_C) {
199		lastconn = *cp++;
200		printf("ctcp %d", lastconn);
201	} else
202		printf("ctcp *");
203
204	/* skip tcp checksum */
205	cp += 2;
206
207	switch (flags & SPECIALS_MASK) {
208	case SPECIAL_I:
209		printf(" *SA+%d", lastlen[dir][lastconn]);
210		break;
211
212	case SPECIAL_D:
213		printf(" *S+%d", lastlen[dir][lastconn]);
214		break;
215
216	default:
217		if (flags & NEW_U)
218			cp = print_sl_change("U=", cp);
219		if (flags & NEW_W)
220			cp = print_sl_winchange(cp);
221		if (flags & NEW_A)
222			cp = print_sl_change("A+", cp);
223		if (flags & NEW_S)
224			cp = print_sl_change("S+", cp);
225		break;
226	}
227	if (flags & NEW_I)
228		cp = print_sl_change("I+", cp);
229
230	/*
231	 * 'hlen' is the length of the uncompressed TCP/IP header (in words).
232	 * 'cp - chdr' is the length of the compressed header.
233	 * 'length - hlen' is the amount of data in the packet.
234	 */
235	hlen = IP_HL(ip);
236	hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);
237	lastlen[dir][lastconn] = length - (hlen << 2);
238	printf(" %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr));
239}
240