xref: /openbsd-src/usr.sbin/tcpdump/print-sl.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e) 
1 /*	$OpenBSD: print-sl.c,v 1.11 2000/10/13 08:32:17 jakob Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1990, 1991, 1993, 1994, 1995, 1996, 1997
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that: (1) source code distributions
9  * retain the above copyright notice and this paragraph in its entirety, (2)
10  * distributions including binary code include the above copyright notice and
11  * this paragraph in its entirety in the documentation or other materials
12  * provided with the distribution, and (3) all advertising materials mentioning
13  * features or use of this software display the following acknowledgement:
14  * ``This product includes software developed by the University of California,
15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16  * the University nor the names of its contributors may be used to endorse
17  * or promote products derived from this software without specific prior
18  * written permission.
19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22  */
23 
24 #ifndef lint
25 static const char rcsid[] =
26     "@(#) $Header: /home/cvs/src/usr.sbin/tcpdump/print-sl.c,v 1.11 2000/10/13 08:32:17 jakob Exp $ (LBL)";
27 #endif
28 
29 #ifdef HAVE_NET_SLIP_H
30 #include <sys/param.h>
31 #include <sys/time.h>
32 #include <sys/timeb.h>
33 #include <sys/file.h>
34 #include <sys/ioctl.h>
35 #include <sys/mbuf.h>
36 #include <sys/socket.h>
37 
38 #ifdef __STDC__
39 struct rtentry;
40 #endif
41 #include <net/if.h>
42 
43 #include <netinet/in.h>
44 #include <netinet/in_systm.h>
45 #include <netinet/ip.h>
46 #include <netinet/if_ether.h>
47 #include <netinet/udp.h>
48 #include <netinet/tcp.h>
49 
50 #include <net/slcompress.h>
51 #include <net/slip.h>
52 
53 #include <ctype.h>
54 #include <netdb.h>
55 #include <pcap.h>
56 #include <stdio.h>
57 
58 #include "interface.h"
59 #include "addrtoname.h"
60 #include "extract.h"			/* must come after interface.h */
61 
62 static u_int lastlen[2][256];
63 static u_int lastconn = 255;
64 
65 static void sliplink_print(const u_char *, const struct ip *, u_int);
66 static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
67 
68 /* XXX BSD/OS 2.1 compatibility */
69 #if !defined(SLIP_HDRLEN) && defined(SLC_BPFHDR)
70 #define SLIP_HDRLEN SLC_BPFHDR
71 #define SLX_DIR 0
72 #define SLX_CHDR (SLC_BPFHDRLEN - 1)
73 #define CHDR_LEN (SLC_BPFHDR - SLC_BPFHDRLEN)
74 #endif
75 
76 /* XXX needs more hacking to work right */
77 
78 void
79 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
80 {
81 	register u_int caplen = h->caplen;
82 	register u_int length = h->len;
83 	register const struct ip *ip;
84 
85 	ts_print(&h->ts);
86 
87 	if (caplen < SLIP_HDRLEN) {
88 		printf("[|slip]");
89 		goto out;
90 	}
91 	/*
92 	 * Some printers want to get back at the link level addresses,
93 	 * and/or check that they're not walking off the end of the packet.
94 	 * Rather than pass them all the way down, we set these globals.
95 	 */
96 	packetp = p;
97 	snapend = p + caplen;
98 
99 	length -= SLIP_HDRLEN;
100 
101 	ip = (struct ip *)(p + SLIP_HDRLEN);
102 
103 	if (eflag)
104 		sliplink_print(p, ip, length);
105 
106 	switch (ip->ip_v) {
107 	case 4:
108 		ip_print((u_char *)ip, length);
109 		break;
110 #ifdef INET6
111 	case 6:
112 		ip6_print((u_char *)ip, length);
113 		break;
114 #endif
115 	default:
116 		printf ("ip v%d", ip->ip_v);
117 	}
118 
119 	if (xflag)
120 		default_print((u_char *)ip, caplen - SLIP_HDRLEN);
121  out:
122 	putchar('\n');
123 }
124 
125 
126 void
127 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
128 {
129 	register u_int caplen = h->caplen;
130 	register u_int length = h->len;
131 	register const struct ip *ip;
132 
133 	ts_print(&h->ts);
134 
135 	if (caplen < SLIP_HDRLEN) {
136 		printf("[|slip]");
137 		goto out;
138 	}
139 	/*
140 	 * Some printers want to get back at the link level addresses,
141 	 * and/or check that they're not walking off the end of the packet.
142 	 * Rather than pass them all the way down, we set these globals.
143 	 */
144 	packetp = p;
145 	snapend = p + caplen;
146 
147 	length -= SLIP_HDRLEN;
148 
149 	ip = (struct ip *)(p + SLIP_HDRLEN);
150 
151 #ifdef notdef
152 	if (eflag)
153 		sliplink_print(p, ip, length);
154 #endif
155 
156 	ip_print((u_char *)ip, length);
157 
158 	if (xflag)
159 		default_print((u_char *)ip, caplen - SLIP_HDRLEN);
160  out:
161 	putchar('\n');
162 }
163 
164 static void
165 sliplink_print(register const u_char *p, register const struct ip *ip,
166 	       register u_int length)
167 {
168 	int dir;
169 	u_int hlen;
170 
171 	dir = p[SLX_DIR];
172 	putchar(dir == SLIPDIR_IN ? 'I' : 'O');
173 	putchar(' ');
174 
175 	if (nflag) {
176 		/* XXX just dump the header */
177 		register int i;
178 
179 		for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
180 			printf("%02x.", p[i]);
181 		printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
182 		return;
183 	}
184 	switch (p[SLX_CHDR] & 0xf0) {
185 
186 	case TYPE_IP:
187 		printf("ip %d: ", length + SLIP_HDRLEN);
188 		break;
189 
190 	case TYPE_UNCOMPRESSED_TCP:
191 		/*
192 		 * The connection id is stored in the IP protocol field.
193 		 * Get it from the link layer since sl_uncompress_tcp()
194 		 * has restored the IP header copy to IPPROTO_TCP.
195 		 */
196 		lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
197 		hlen = ip->ip_hl;
198 		hlen += ((struct tcphdr *)&((int *)ip)[hlen])->th_off;
199 		lastlen[dir][lastconn] = length - (hlen << 2);
200 		printf("utcp %d: ", lastconn);
201 		break;
202 
203 	default:
204 		if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
205 			compressed_sl_print(&p[SLX_CHDR], ip,
206 			    length, dir);
207 			printf(": ");
208 		} else
209 			printf("slip-%d!: ", p[SLX_CHDR]);
210 	}
211 }
212 
213 static const u_char *
214 print_sl_change(const char *str, register const u_char *cp)
215 {
216 	register u_int i;
217 
218 	if ((i = *cp++) == 0) {
219 		i = EXTRACT_16BITS(cp);
220 		cp += 2;
221 	}
222 	printf(" %s%d", str, i);
223 	return (cp);
224 }
225 
226 static const u_char *
227 print_sl_winchange(register const u_char *cp)
228 {
229 	register short i;
230 
231 	if ((i = *cp++) == 0) {
232 		i = EXTRACT_16BITS(cp);
233 		cp += 2;
234 	}
235 	if (i >= 0)
236 		printf(" W+%d", i);
237 	else
238 		printf(" W%d", i);
239 	return (cp);
240 }
241 
242 static void
243 compressed_sl_print(const u_char *chdr, const struct ip *ip,
244 		    u_int length, int dir)
245 {
246 	register const u_char *cp = chdr;
247 	register u_int flags, hlen;
248 
249 	flags = *cp++;
250 	if (flags & NEW_C) {
251 		lastconn = *cp++;
252 		printf("ctcp %d", lastconn);
253 	} else
254 		printf("ctcp *");
255 
256 	/* skip tcp checksum */
257 	cp += 2;
258 
259 	switch (flags & SPECIALS_MASK) {
260 	case SPECIAL_I:
261 		printf(" *SA+%d", lastlen[dir][lastconn]);
262 		break;
263 
264 	case SPECIAL_D:
265 		printf(" *S+%d", lastlen[dir][lastconn]);
266 		break;
267 
268 	default:
269 		if (flags & NEW_U)
270 			cp = print_sl_change("U=", cp);
271 		if (flags & NEW_W)
272 			cp = print_sl_winchange(cp);
273 		if (flags & NEW_A)
274 			cp = print_sl_change("A+", cp);
275 		if (flags & NEW_S)
276 			cp = print_sl_change("S+", cp);
277 		break;
278 	}
279 	if (flags & NEW_I)
280 		cp = print_sl_change("I+", cp);
281 
282 	/*
283 	 * 'hlen' is the length of the uncompressed TCP/IP header (in words).
284 	 * 'cp - chdr' is the length of the compressed header.
285 	 * 'length - hlen' is the amount of data in the packet.
286 	 */
287 	hlen = ip->ip_hl;
288 	hlen += ((struct tcphdr *)&((int32_t *)ip)[hlen])->th_off;
289 	lastlen[dir][lastconn] = length - (hlen << 2);
290 	printf(" %d (%d)", lastlen[dir][lastconn], (int)(cp - chdr));
291 }
292 #else
293 #include <sys/types.h>
294 #include <sys/time.h>
295 
296 #include <pcap.h>
297 #include <stdio.h>
298 
299 #include "interface.h"
300 
301 void
302 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
303 {
304 
305 	error("not configured for slip");
306 	/* NOTREACHED */
307 }
308 
309 void
310 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
311 {
312 
313 	error("not configured for slip");
314 	/* NOTREACHED */
315 }
316 #endif
317