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 * $FreeBSD$
22 */
23
24#ifndef lint
25static const char rcsid[] _U_ =
26    "@(#) $Header: /tcpdump/master/tcpdump/print-sl.c,v 1.65 2005-04-06 21:32:42 mcr Exp $ (LBL)";
27#endif
28
29#ifdef HAVE_CONFIG_H
30#include "config.h"
31#endif
32
33#include <tcpdump-stdinc.h>
34
35#include <pcap.h>
36#include <stdio.h>
37
38#include "interface.h"
39#include "addrtoname.h"
40#include "extract.h"			/* must come after interface.h */
41
42#include "ip.h"
43#include "tcp.h"
44#include "slip.h"
45#include "slcompress.h"
46
47static u_int lastlen[2][256];
48static u_int lastconn = 255;
49
50static void sliplink_print(const u_char *, const struct ip *, u_int);
51static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
52
53u_int
54sl_if_print(const struct pcap_pkthdr *h, const u_char *p)
55{
56	register u_int caplen = h->caplen;
57	register u_int length = h->len;
58	register const struct ip *ip;
59
60	if (caplen < SLIP_HDRLEN) {
61		printf("[|slip]");
62		return (caplen);
63	}
64
65	length -= SLIP_HDRLEN;
66
67	ip = (struct ip *)(p + SLIP_HDRLEN);
68
69	if (eflag)
70		sliplink_print(p, ip, length);
71
72	switch (IP_V(ip)) {
73	case 4:
74	        ip_print(gndo, (u_char *)ip, length);
75		break;
76#ifdef INET6
77	case 6:
78		ip6_print(gndo, (u_char *)ip, length);
79		break;
80#endif
81	default:
82		printf ("ip v%d", IP_V(ip));
83	}
84
85	return (SLIP_HDRLEN);
86}
87
88u_int
89sl_bsdos_if_print(const struct pcap_pkthdr *h, const u_char *p)
90{
91	register u_int caplen = h->caplen;
92	register u_int length = h->len;
93	register const struct ip *ip;
94
95	if (caplen < SLIP_HDRLEN) {
96		printf("[|slip]");
97		return (caplen);
98	}
99
100	length -= SLIP_HDRLEN;
101
102	ip = (struct ip *)(p + SLIP_HDRLEN);
103
104#ifdef notdef
105	if (eflag)
106		sliplink_print(p, ip, length);
107#endif
108
109	ip_print(gndo, (u_char *)ip, length);
110
111	return (SLIP_HDRLEN);
112}
113
114static void
115sliplink_print(register const u_char *p, register const struct ip *ip,
116	       register u_int length)
117{
118	int dir;
119	u_int hlen;
120
121	dir = p[SLX_DIR];
122	putchar(dir == SLIPDIR_IN ? 'I' : 'O');
123	putchar(' ');
124
125	if (nflag) {
126		/* XXX just dump the header */
127		register int i;
128
129		for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
130			printf("%02x.", p[i]);
131		printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
132		return;
133	}
134	switch (p[SLX_CHDR] & 0xf0) {
135
136	case TYPE_IP:
137		printf("ip %d: ", length + SLIP_HDRLEN);
138		break;
139
140	case TYPE_UNCOMPRESSED_TCP:
141		/*
142		 * The connection id is stored in the IP protocol field.
143		 * Get it from the link layer since sl_uncompress_tcp()
144		 * has restored the IP header copy to IPPROTO_TCP.
145		 */
146		lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
147		hlen = IP_HL(ip);
148		hlen += TH_OFF((struct tcphdr *)&((int *)ip)[hlen]);
149		lastlen[dir][lastconn] = length - (hlen << 2);
150		printf("utcp %d: ", lastconn);
151		break;
152
153	default:
154		if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
155			compressed_sl_print(&p[SLX_CHDR], ip,
156			    length, dir);
157			printf(": ");
158		} else
159			printf("slip-%d!: ", p[SLX_CHDR]);
160	}
161}
162
163static const u_char *
164print_sl_change(const char *str, register const u_char *cp)
165{
166	register u_int i;
167
168	if ((i = *cp++) == 0) {
169		i = EXTRACT_16BITS(cp);
170		cp += 2;
171	}
172	printf(" %s%d", str, i);
173	return (cp);
174}
175
176static const u_char *
177print_sl_winchange(register const u_char *cp)
178{
179	register short i;
180
181	if ((i = *cp++) == 0) {
182		i = EXTRACT_16BITS(cp);
183		cp += 2;
184	}
185	if (i >= 0)
186		printf(" W+%d", i);
187	else
188		printf(" W%d", i);
189	return (cp);
190}
191
192static void
193compressed_sl_print(const u_char *chdr, const struct ip *ip,
194		    u_int length, int dir)
195{
196	register const u_char *cp = chdr;
197	register u_int flags, hlen;
198
199	flags = *cp++;
200	if (flags & NEW_C) {
201		lastconn = *cp++;
202		printf("ctcp %d", lastconn);
203	} else
204		printf("ctcp *");
205
206	/* skip tcp checksum */
207	cp += 2;
208
209	switch (flags & SPECIALS_MASK) {
210	case SPECIAL_I:
211		printf(" *SA+%d", lastlen[dir][lastconn]);
212		break;
213
214	case SPECIAL_D:
215		printf(" *S+%d", lastlen[dir][lastconn]);
216		break;
217
218	default:
219		if (flags & NEW_U)
220			cp = print_sl_change("U=", cp);
221		if (flags & NEW_W)
222			cp = print_sl_winchange(cp);
223		if (flags & NEW_A)
224			cp = print_sl_change("A+", cp);
225		if (flags & NEW_S)
226			cp = print_sl_change("S+", cp);
227		break;
228	}
229	if (flags & NEW_I)
230		cp = print_sl_change("I+", cp);
231
232	/*
233	 * 'hlen' is the length of the uncompressed TCP/IP header (in words).
234	 * 'cp - chdr' is the length of the compressed header.
235	 * 'length - hlen' is the amount of data in the packet.
236	 */
237	hlen = IP_HL(ip);
238	hlen += TH_OFF((struct tcphdr *)&((int32_t *)ip)[hlen]);
239	lastlen[dir][lastconn] = length - (hlen << 2);
240	printf(" %d (%ld)", lastlen[dir][lastconn], (long)(cp - chdr));
241}
242