print-bootp.c revision 1.6 
1/*
2 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
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 * Format and print bootp packets.
22 */
23#ifndef lint
24static const char rcsid[] =
25    "@(#) $Header: /usr/local/opengrok/home/cvs-mirror/mirrors/openbsd/src/usr.sbin/tcpdump/print-bootp.c,v 1.6 1997/07/25 20:12:22 mickey Exp $ (LBL)";
26#endif
27
28#include <sys/param.h>
29#include <sys/time.h>
30#include <sys/socket.h>
31
32#ifdef __STDC__
33struct mbuf;
34struct rtentry;
35#endif
36#include <net/if.h>
37
38#include <netinet/in.h>
39#include <netinet/if_ether.h>
40
41#include <ctype.h>
42#include <stdio.h>
43#include <string.h>
44
45#include "interface.h"
46#include "addrtoname.h"
47#include "bootp.h"
48
49static void rfc1048_print(const u_char *, u_int);
50static void cmu_print(const u_char *, u_int);
51
52static char tstr[] = " [|bootp]";
53
54/*
55 * Print bootp requests
56 */
57void
58bootp_print(register const u_char *cp, u_int length,
59	    u_short sport, u_short dport)
60{
61	register const struct bootp *bp;
62	static u_char vm_cmu[4] = VM_CMU;
63	static u_char vm_rfc1048[4] = VM_RFC1048;
64
65	bp = (struct bootp *)cp;
66	TCHECK(bp->bp_op);
67	switch (bp->bp_op) {
68
69	case BOOTREQUEST:
70		/* Usually, a request goes from a client to a server */
71		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
72			printf(" (request)");
73		break;
74
75	case BOOTREPLY:
76		/* Usually, a reply goes from a server to a client */
77		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
78			printf(" (reply)");
79		break;
80
81	default:
82		printf(" bootp-#%d", bp->bp_op);
83	}
84
85	TCHECK(bp->bp_secs);
86
87	/* The usual hardware address type is 1 (10Mb Ethernet) */
88	if (bp->bp_htype != 1)
89		printf(" htype-#%d", bp->bp_htype);
90
91	/* The usual length for 10Mb Ethernet address is 6 bytes */
92	if (bp->bp_htype != 1 || bp->bp_hlen != 6)
93		printf(" hlen:%d", bp->bp_hlen);
94
95	/* Only print interesting fields */
96	if (bp->bp_hops)
97		printf(" hops:%d", bp->bp_hops);
98	if (bp->bp_xid)
99		printf(" xid:0x%x", (u_int32_t)ntohl(bp->bp_xid));
100	if (bp->bp_secs)
101		printf(" secs:%d", ntohs(bp->bp_secs));
102
103	/* Client's ip address */
104	TCHECK(bp->bp_ciaddr);
105	if (bp->bp_ciaddr.s_addr)
106		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
107
108	/* 'your' ip address (bootp client) */
109	TCHECK(bp->bp_yiaddr);
110	if (bp->bp_yiaddr.s_addr)
111		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
112
113	/* Server's ip address */
114	TCHECK(bp->bp_siaddr);
115	if (bp->bp_siaddr.s_addr)
116		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
117
118	/* Gateway's ip address */
119	TCHECK(bp->bp_giaddr);
120	if (bp->bp_giaddr.s_addr)
121		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
122
123	/* Client's Ethernet address */
124	if (bp->bp_htype == 1 && bp->bp_hlen == 6) {
125		register const struct ether_header *eh;
126		register const char *e;
127
128		TCHECK2(bp->bp_chaddr[0], 6);
129		eh = (struct ether_header *)packetp;
130		if (bp->bp_op == BOOTREQUEST)
131			e = (const char *)ESRC(eh);
132		else if (bp->bp_op == BOOTREPLY)
133			e = (const char *)EDST(eh);
134		else
135			e = 0;
136		if (e == 0 || memcmp((char *)bp->bp_chaddr, e, 6) != 0)
137			printf(" ether %s", etheraddr_string(bp->bp_chaddr));
138	}
139
140	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
141	if (*bp->bp_sname) {
142		printf(" sname \"");
143		if (fn_print(bp->bp_sname, snapend)) {
144			putchar('"');
145			fputs(tstr + 1, stdout);
146			return;
147		}
148	}
149	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
150	if (*bp->bp_file) {
151		printf(" file \"");
152		if (fn_print(bp->bp_file, snapend)) {
153			putchar('"');
154			fputs(tstr + 1, stdout);
155			return;
156		}
157	}
158
159	/* Decode the vendor buffer */
160	TCHECK(bp->bp_vend[0]);
161	length -= sizeof(*bp) - sizeof(bp->bp_vend);
162	if (memcmp((char *)bp->bp_vend, (char *)vm_rfc1048,
163		 sizeof(u_int32_t)) == 0)
164		rfc1048_print(bp->bp_vend, length);
165	else if (memcmp((char *)bp->bp_vend, (char *)vm_cmu,
166		      sizeof(u_int32_t)) == 0)
167		cmu_print(bp->bp_vend, length);
168	else {
169		u_int32_t ul;
170
171		memcpy((char *)&ul, (char *)bp->bp_vend, sizeof(ul));
172		if (ul != 0)
173			printf("vend-#0x%x", ul);
174	}
175
176	return;
177trunc:
178	fputs(tstr, stdout);
179}
180
181/* The first character specifies the format to print */
182static struct tok tag2str[] = {
183/* RFC1048 tags */
184	{ TAG_PAD,		" PAD" },
185	{ TAG_SUBNET_MASK,	"iSM" },	/* subnet mask (RFC950) */
186	{ TAG_TIME_OFFSET,	"lTZ" },	/* seconds from UTC */
187	{ TAG_GATEWAY,		"iDG" },	/* default gateway */
188	{ TAG_TIME_SERVER,	"iTS" },	/* time servers (RFC868) */
189	{ TAG_NAME_SERVER,	"iIEN" },	/* IEN name servers (IEN116) */
190	{ TAG_DOMAIN_SERVER,	"iNS" },	/* domain name (RFC1035) */
191	{ TAG_LOG_SERVER,	"iLOG" },	/* MIT log servers */
192	{ TAG_COOKIE_SERVER,	"iCS" },	/* cookie servers (RFC865) */
193	{ TAG_LPR_SERVER,	"iLPR" },	/* lpr server (RFC1179) */
194	{ TAG_IMPRESS_SERVER,	"iIM" },	/* impress servers (Imagen) */
195	{ TAG_RLP_SERVER,	"iRL" },	/* resource location (RFC887) */
196	{ TAG_HOSTNAME,		"aHN" },	/* ascii hostname */
197	{ TAG_BOOTSIZE,		"sBS" },	/* 512 byte blocks */
198	{ TAG_END,		" END" },
199/* RFC1497 tags */
200	{ TAG_DUMPPATH,		"aDP" },
201	{ TAG_DOMAINNAME,	"aDN" },
202	{ TAG_SWAP_SERVER,	"iSS" },
203	{ TAG_ROOTPATH,		"aRP" },
204	{ TAG_EXTPATH,		"aEP" },
205	{ 0,			NULL }
206};
207
208static void
209rfc1048_print(register const u_char *bp, register u_int length)
210{
211	register u_char tag;
212	register u_int len, size;
213	register const char *cp;
214	register char c;
215	int first;
216	u_int32_t ul;
217	u_short us;
218
219	printf(" vend-rfc1048");
220
221	/* Step over magic cookie */
222	bp += sizeof(int32_t);
223
224	/* Loop while we there is a tag left in the buffer */
225	while (bp + 1 < snapend) {
226		tag = *bp++;
227		if (tag == TAG_PAD)
228			continue;
229		if (tag == TAG_END)
230			return;
231		cp = tok2str(tag2str, "?T%d", tag);
232		c = *cp++;
233		printf(" %s:", cp);
234
235		/* Get the length; check for truncation */
236		if (bp + 1 >= snapend) {
237			fputs(tstr, stdout);
238			return;
239		}
240		len = *bp++;
241		if (bp + len >= snapend) {
242			fputs(tstr, stdout);
243			return;
244		}
245
246		/* Print data */
247		size = len;
248		if (c == '?') {
249			/* Base default formats for unknown tags on data size */
250			if (size & 1)
251				c = 'b';
252			else if (size & 2)
253				c = 's';
254			else
255				c = 'l';
256		}
257		first = 1;
258		switch (c) {
259
260		case 'a':
261			/* ascii strings */
262			putchar('"');
263			(void)fn_printn(bp, size, NULL);
264			putchar('"');
265			bp += size;
266			size = 0;
267			break;
268
269		case 'i':
270		case 'l':
271			/* ip addresses/32-bit words */
272			while (size >= sizeof(ul)) {
273				if (!first)
274					putchar(',');
275				memcpy((char *)&ul, (char *)bp, sizeof(ul));
276				if (c == 'i')
277					printf("%s", ipaddr_string(&ul));
278				else
279					printf("%u", ul);
280				bp += sizeof(ul);
281				size -= sizeof(ul);
282				first = 0;
283			}
284			break;
285
286		case 's':
287			/* shorts */
288			while (size >= sizeof(us)) {
289				if (!first)
290					putchar(',');
291				memcpy((char *)&us, (char *)bp, sizeof(us));
292				printf("%d", us);
293				bp += sizeof(us);
294				size -= sizeof(us);
295				first = 0;
296			}
297			break;
298
299		case 'b':
300		default:
301			/* Bytes */
302			while (size > 0) {
303				if (!first)
304					putchar('.');
305				printf("%d", *bp);
306				++bp;
307				--size;
308				first = 0;
309			}
310			break;
311		}
312		/* Data left over? */
313		if (size)
314			printf("[len %d]", len);
315	}
316}
317
318static void
319cmu_print(register const u_char *bp, register u_int length)
320{
321	register const struct cmu_vend *cmu;
322	char *fmt = " %s:%s";
323
324#define PRINTCMUADDR(m, s) { TCHECK(cmu->m); \
325    if (cmu->m.s_addr != 0) \
326	printf(fmt, s, ipaddr_string(&cmu->m.s_addr)); }
327
328	printf(" vend-cmu");
329	cmu = (struct cmu_vend *)bp;
330
331	/* Only print if there are unknown bits */
332	TCHECK(cmu->v_flags);
333	if ((cmu->v_flags & ~(VF_SMASK)) != 0)
334		printf(" F:0x%x", cmu->v_flags);
335	PRINTCMUADDR(v_dgate, "DG");
336	PRINTCMUADDR(v_smask, cmu->v_flags & VF_SMASK ? "SM" : "SM*");
337	PRINTCMUADDR(v_dns1, "NS1");
338	PRINTCMUADDR(v_dns2, "NS2");
339	PRINTCMUADDR(v_ins1, "IEN1");
340	PRINTCMUADDR(v_ins2, "IEN2");
341	PRINTCMUADDR(v_ts1, "TS1");
342	PRINTCMUADDR(v_ts2, "TS2");
343	return;
344
345trunc:
346	fputs(tstr, stdout);
347#undef PRINTCMUADDR
348}
349