xref: /freebsd/contrib/tcpdump/print-sl.c (revision 380a989b3223d455375b4fae70fd0b9bdd43bafb)
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
23 static const char rcsid[] =
24     "@(#) $Header: print-sl.c,v 1.42 97/06/12 14:21:35 leres Exp $ (LBL)";
25 #endif
26 
27 #ifdef HAVE_NET_SLIP_H
28 #include <sys/param.h>
29 #include <sys/time.h>
30 #include <sys/timeb.h>
31 #include <sys/file.h>
32 #include <sys/ioctl.h>
33 #include <sys/mbuf.h>
34 #include <sys/socket.h>
35 
36 #if __STDC__
37 struct rtentry;
38 #endif
39 #include <net/if.h>
40 
41 #include <netinet/in.h>
42 #include <netinet/in_systm.h>
43 #include <netinet/ip.h>
44 #include <net/ethernet.h>
45 #include <netinet/ip_var.h>
46 #include <netinet/udp.h>
47 #include <netinet/udp_var.h>
48 #include <netinet/tcp.h>
49 #include <netinet/tcpip.h>
50 
51 #include <net/slcompress.h>
52 #include <net/slip.h>
53 
54 #include <ctype.h>
55 #include <netdb.h>
56 #include <pcap.h>
57 #include <stdio.h>
58 
59 #include "interface.h"
60 #include "addrtoname.h"
61 #include "extract.h"			/* must come after interface.h */
62 
63 static u_int lastlen[2][256];
64 static u_int lastconn = 255;
65 
66 static void sliplink_print(const u_char *, const struct ip *, u_int);
67 static void compressed_sl_print(const u_char *, const struct ip *, u_int, int);
68 
69 /* XXX BSD/OS 2.1 compatibility */
70 #if !defined(SLIP_HDRLEN) && defined(SLC_BPFHDR)
71 #define SLIP_HDRLEN SLC_BPFHDR
72 #define SLX_DIR 0
73 #define SLX_CHDR (SLC_BPFHDRLEN - 1)
74 #define CHDR_LEN (SLC_BPFHDR - SLC_BPFHDRLEN)
75 #endif
76 
77 /* XXX needs more hacking to work right */
78 
79 void
80 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
81 {
82 	register u_int caplen = h->caplen;
83 	register u_int length = h->len;
84 	register const struct ip *ip;
85 
86 	ts_print(&h->ts);
87 
88 	if (caplen < SLIP_HDRLEN) {
89 		printf("[|slip]");
90 		goto out;
91 	}
92 	/*
93 	 * Some printers want to get back at the link level addresses,
94 	 * and/or check that they're not walking off the end of the packet.
95 	 * Rather than pass them all the way down, we set these globals.
96 	 */
97 	packetp = p;
98 	snapend = p + caplen;
99 
100 	length -= SLIP_HDRLEN;
101 
102 	ip = (struct ip *)(p + SLIP_HDRLEN);
103 
104 	if (eflag)
105 		sliplink_print(p, ip, length);
106 
107 	ip_print((u_char *)ip, length);
108 
109 	if (xflag)
110 		default_print((u_char *)ip, caplen - SLIP_HDRLEN);
111  out:
112 	putchar('\n');
113 }
114 
115 
116 void
117 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
118 {
119 	register u_int caplen = h->caplen;
120 	register u_int length = h->len;
121 	register const struct ip *ip;
122 
123 	ts_print(&h->ts);
124 
125 	if (caplen < SLIP_HDRLEN) {
126 		printf("[|slip]");
127 		goto out;
128 	}
129 	/*
130 	 * Some printers want to get back at the link level addresses,
131 	 * and/or check that they're not walking off the end of the packet.
132 	 * Rather than pass them all the way down, we set these globals.
133 	 */
134 	packetp = p;
135 	snapend = p + caplen;
136 
137 	length -= SLIP_HDRLEN;
138 
139 	ip = (struct ip *)(p + SLIP_HDRLEN);
140 
141 #ifdef notdef
142 	if (eflag)
143 		sliplink_print(p, ip, length);
144 #endif
145 
146 	ip_print((u_char *)ip, length);
147 
148 	if (xflag)
149 		default_print((u_char *)ip, caplen - SLIP_HDRLEN);
150  out:
151 	putchar('\n');
152 }
153 
154 static void
155 sliplink_print(register const u_char *p, register const struct ip *ip,
156 	       register u_int length)
157 {
158 	int dir;
159 	u_int hlen;
160 
161 	dir = p[SLX_DIR];
162 	putchar(dir == SLIPDIR_IN ? 'I' : 'O');
163 	putchar(' ');
164 
165 	if (nflag) {
166 		/* XXX just dump the header */
167 		register int i;
168 
169 		for (i = SLX_CHDR; i < SLX_CHDR + CHDR_LEN - 1; ++i)
170 			printf("%02x.", p[i]);
171 		printf("%02x: ", p[SLX_CHDR + CHDR_LEN - 1]);
172 		return;
173 	}
174 	switch (p[SLX_CHDR] & 0xf0) {
175 
176 	case TYPE_IP:
177 		printf("ip %d: ", length + SLIP_HDRLEN);
178 		break;
179 
180 	case TYPE_UNCOMPRESSED_TCP:
181 		/*
182 		 * The connection id is stored in the IP protocol field.
183 		 * Get it from the link layer since sl_uncompress_tcp()
184 		 * has restored the IP header copy to IPPROTO_TCP.
185 		 */
186 		lastconn = ((struct ip *)&p[SLX_CHDR])->ip_p;
187 		hlen = ip->ip_hl;
188 		hlen += ((struct tcphdr *)&((int *)ip)[hlen])->th_off;
189 		lastlen[dir][lastconn] = length - (hlen << 2);
190 		printf("utcp %d: ", lastconn);
191 		break;
192 
193 	default:
194 		if (p[SLX_CHDR] & TYPE_COMPRESSED_TCP) {
195 			compressed_sl_print(&p[SLX_CHDR], ip,
196 			    length, dir);
197 			printf(": ");
198 		} else
199 			printf("slip-%d!: ", p[SLX_CHDR]);
200 	}
201 }
202 
203 static const u_char *
204 print_sl_change(const char *str, register const u_char *cp)
205 {
206 	register u_int i;
207 
208 	if ((i = *cp++) == 0) {
209 		i = EXTRACT_16BITS(cp);
210 		cp += 2;
211 	}
212 	printf(" %s%d", str, i);
213 	return (cp);
214 }
215 
216 static const u_char *
217 print_sl_winchange(register const u_char *cp)
218 {
219 	register short i;
220 
221 	if ((i = *cp++) == 0) {
222 		i = EXTRACT_16BITS(cp);
223 		cp += 2;
224 	}
225 	if (i >= 0)
226 		printf(" W+%d", i);
227 	else
228 		printf(" W%d", i);
229 	return (cp);
230 }
231 
232 static void
233 compressed_sl_print(const u_char *chdr, const struct ip *ip,
234 		    u_int length, int dir)
235 {
236 	register const u_char *cp = chdr;
237 	register u_int flags, hlen;
238 
239 	flags = *cp++;
240 	if (flags & NEW_C) {
241 		lastconn = *cp++;
242 		printf("ctcp %d", lastconn);
243 	} else
244 		printf("ctcp *");
245 
246 	/* skip tcp checksum */
247 	cp += 2;
248 
249 	switch (flags & SPECIALS_MASK) {
250 	case SPECIAL_I:
251 		printf(" *SA+%d", lastlen[dir][lastconn]);
252 		break;
253 
254 	case SPECIAL_D:
255 		printf(" *S+%d", lastlen[dir][lastconn]);
256 		break;
257 
258 	default:
259 		if (flags & NEW_U)
260 			cp = print_sl_change("U=", cp);
261 		if (flags & NEW_W)
262 			cp = print_sl_winchange(cp);
263 		if (flags & NEW_A)
264 			cp = print_sl_change("A+", cp);
265 		if (flags & NEW_S)
266 			cp = print_sl_change("S+", cp);
267 		break;
268 	}
269 	if (flags & NEW_I)
270 		cp = print_sl_change("I+", cp);
271 
272 	/*
273 	 * 'hlen' is the length of the uncompressed TCP/IP header (in words).
274 	 * 'cp - chdr' is the length of the compressed header.
275 	 * 'length - hlen' is the amount of data in the packet.
276 	 */
277 	hlen = ip->ip_hl;
278 	hlen += ((struct tcphdr *)&((int32_t *)ip)[hlen])->th_off;
279 	lastlen[dir][lastconn] = length - (hlen << 2);
280 	printf(" %d (%d)", lastlen[dir][lastconn], cp - chdr);
281 }
282 #else
283 #include <sys/types.h>
284 #include <sys/time.h>
285 
286 #include <pcap.h>
287 #include <stdio.h>
288 
289 #include "interface.h"
290 
291 void
292 sl_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
293 {
294 
295 	error("not configured for slip");
296 	/* NOTREACHED */
297 }
298 
299 void
300 sl_bsdos_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
301 {
302 
303 	error("not configured for slip");
304 	/* NOTREACHED */
305 }
306 #endif
307