print-bootp.c revision 1.8 
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 1.8 1999/07/28 20:41:36 jakob 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 <memory.h>
43#include <stdio.h>
44#include <string.h>
45
46#include "interface.h"
47#include "addrtoname.h"
48#include "bootp.h"
49
50static void rfc1048_print(const u_char *, u_int);
51static void cmu_print(const u_char *, u_int);
52
53static char tstr[] = " [|bootp]";
54
55/*
56 * Print bootp requests
57 */
58void
59bootp_print(register const u_char *cp, u_int length,
60	    u_short sport, u_short dport)
61{
62	register const struct bootp *bp;
63	static u_char vm_cmu[4] = VM_CMU;
64	static u_char vm_rfc1048[4] = VM_RFC1048;
65
66	bp = (struct bootp *)cp;
67	TCHECK(bp->bp_op);
68	switch (bp->bp_op) {
69
70	case BOOTREQUEST:
71		/* Usually, a request goes from a client to a server */
72		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
73			printf(" (request)");
74		break;
75
76	case BOOTREPLY:
77		/* Usually, a reply goes from a server to a client */
78		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
79			printf(" (reply)");
80		break;
81
82	default:
83		printf(" bootp-#%d", bp->bp_op);
84	}
85
86	TCHECK(bp->bp_secs);
87
88	/* The usual hardware address type is 1 (10Mb Ethernet) */
89	if (bp->bp_htype != 1)
90		printf(" htype-#%d", bp->bp_htype);
91
92	/* The usual length for 10Mb Ethernet address is 6 bytes */
93	if (bp->bp_htype != 1 || bp->bp_hlen != 6)
94		printf(" hlen:%d", bp->bp_hlen);
95
96	/* Only print interesting fields */
97	if (bp->bp_hops)
98		printf(" hops:%d", bp->bp_hops);
99	if (bp->bp_xid)
100		printf(" xid:0x%x", (u_int32_t)ntohl(bp->bp_xid));
101	if (bp->bp_secs)
102		printf(" secs:%d", ntohs(bp->bp_secs));
103
104	/* Client's ip address */
105	TCHECK(bp->bp_ciaddr);
106	if (bp->bp_ciaddr.s_addr)
107		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
108
109	/* 'your' ip address (bootp client) */
110	TCHECK(bp->bp_yiaddr);
111	if (bp->bp_yiaddr.s_addr)
112		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
113
114	/* Server's ip address */
115	TCHECK(bp->bp_siaddr);
116	if (bp->bp_siaddr.s_addr)
117		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
118
119	/* Gateway's ip address */
120	TCHECK(bp->bp_giaddr);
121	if (bp->bp_giaddr.s_addr)
122		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
123
124	/* Client's Ethernet address */
125	if (bp->bp_htype == 1 && bp->bp_hlen == 6) {
126		register const struct ether_header *eh;
127		register const char *e;
128
129		TCHECK2(bp->bp_chaddr[0], 6);
130		eh = (struct ether_header *)packetp;
131		if (bp->bp_op == BOOTREQUEST)
132			e = (const char *)ESRC(eh);
133		else if (bp->bp_op == BOOTREPLY)
134			e = (const char *)EDST(eh);
135		else
136			e = 0;
137		if (e == 0 || memcmp((char *)bp->bp_chaddr, e, 6) != 0)
138			printf(" ether %s", etheraddr_string(bp->bp_chaddr));
139	}
140
141	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
142	if (*bp->bp_sname) {
143		printf(" sname \"");
144		if (fn_print(bp->bp_sname, snapend)) {
145			putchar('"');
146			fputs(tstr + 1, stdout);
147			return;
148		}
149		putchar('"');
150	}
151	TCHECK2(bp->bp_file[0], 1);		/* check first char only */
152	if (*bp->bp_file) {
153		printf(" file \"");
154		if (fn_print(bp->bp_file, snapend)) {
155			putchar('"');
156			fputs(tstr + 1, stdout);
157			return;
158		}
159		putchar('"');
160	}
161
162	/* Decode the vendor buffer */
163	TCHECK(bp->bp_vend[0]);
164	length -= sizeof(*bp) - sizeof(bp->bp_vend);
165	if (memcmp((char *)bp->bp_vend, (char *)vm_rfc1048,
166		 sizeof(u_int32_t)) == 0)
167		rfc1048_print(bp->bp_vend, length);
168	else if (memcmp((char *)bp->bp_vend, (char *)vm_cmu,
169		      sizeof(u_int32_t)) == 0)
170		cmu_print(bp->bp_vend, length);
171	else {
172		u_int32_t ul;
173
174		memcpy((char *)&ul, (char *)bp->bp_vend, sizeof(ul));
175		if (ul != 0)
176			printf("vend-#0x%x", ul);
177	}
178
179	return;
180trunc:
181	fputs(tstr, stdout);
182}
183
184/* The first character specifies the format to print */
185static struct tok tag2str[] = {
186/* RFC1048 tags */
187	{ TAG_PAD,		" PAD" },
188	{ TAG_SUBNET_MASK,	"iSM" },	/* subnet mask (RFC950) */
189	{ TAG_TIME_OFFSET,	"lTZ" },	/* seconds from UTC */
190	{ TAG_GATEWAY,		"iDG" },	/* default gateway */
191	{ TAG_TIME_SERVER,	"iTS" },	/* time servers (RFC868) */
192	{ TAG_NAME_SERVER,	"iIEN" },	/* IEN name servers (IEN116) */
193	{ TAG_DOMAIN_SERVER,	"iNS" },	/* domain name (RFC1035) */
194	{ TAG_LOG_SERVER,	"iLOG" },	/* MIT log servers */
195	{ TAG_COOKIE_SERVER,	"iCS" },	/* cookie servers (RFC865) */
196	{ TAG_LPR_SERVER,	"iLPR" },	/* lpr server (RFC1179) */
197	{ TAG_IMPRESS_SERVER,	"iIM" },	/* impress servers (Imagen) */
198	{ TAG_RLP_SERVER,	"iRL" },	/* resource location (RFC887) */
199	{ TAG_HOSTNAME,		"aHN" },	/* ascii hostname */
200	{ TAG_BOOTSIZE,		"sBS" },	/* 512 byte blocks */
201	{ TAG_END,		" END" },
202/* RFC1497 tags */
203	{ TAG_DUMPPATH,		"aDP" },
204	{ TAG_DOMAINNAME,	"aDN" },
205	{ TAG_SWAP_SERVER,	"iSS" },
206	{ TAG_ROOTPATH,		"aRP" },
207	{ TAG_EXTPATH,		"aEP" },
208	{ 0,			NULL }
209};
210
211static void
212rfc1048_print(register const u_char *bp, register u_int length)
213{
214	register u_char tag;
215	register u_int len, size;
216	register const char *cp;
217	register char c;
218	int first;
219	u_int32_t ul;
220	u_short us;
221
222	printf(" vend-rfc1048");
223
224	/* Step over magic cookie */
225	bp += sizeof(int32_t);
226
227	/* Loop while we there is a tag left in the buffer */
228	while (bp + 1 < snapend) {
229		tag = *bp++;
230		if (tag == TAG_PAD)
231			continue;
232		if (tag == TAG_END)
233			return;
234		cp = tok2str(tag2str, "?T%d", tag);
235		c = *cp++;
236		printf(" %s:", cp);
237
238		/* Get the length; check for truncation */
239		if (bp + 1 >= snapend) {
240			fputs(tstr, stdout);
241			return;
242		}
243		len = *bp++;
244		if (bp + len >= snapend) {
245			fputs(tstr, stdout);
246			return;
247		}
248
249		/* Print data */
250		size = len;
251		if (c == '?') {
252			/* Base default formats for unknown tags on data size */
253			if (size & 1)
254				c = 'b';
255			else if (size & 2)
256				c = 's';
257			else
258				c = 'l';
259		}
260		first = 1;
261		switch (c) {
262
263		case 'a':
264			/* ascii strings */
265			putchar('"');
266			(void)fn_printn(bp, size, NULL);
267			putchar('"');
268			bp += size;
269			size = 0;
270			break;
271
272		case 'i':
273		case 'l':
274			/* ip addresses/32-bit words */
275			while (size >= sizeof(ul)) {
276				if (!first)
277					putchar(',');
278				memcpy((char *)&ul, (char *)bp, sizeof(ul));
279				if (c == 'i')
280					printf("%s", ipaddr_string(&ul));
281				else
282					printf("%u", ul);
283				bp += sizeof(ul);
284				size -= sizeof(ul);
285				first = 0;
286			}
287			break;
288
289		case 's':
290			/* shorts */
291			while (size >= sizeof(us)) {
292				if (!first)
293					putchar(',');
294				memcpy((char *)&us, (char *)bp, sizeof(us));
295				printf("%d", us);
296				bp += sizeof(us);
297				size -= sizeof(us);
298				first = 0;
299			}
300			break;
301
302		case 'b':
303		default:
304			/* Bytes */
305			while (size > 0) {
306				if (!first)
307					putchar('.');
308				printf("%d", *bp);
309				++bp;
310				--size;
311				first = 0;
312			}
313			break;
314		}
315		/* Data left over? */
316		if (size)
317			printf("[len %d]", len);
318	}
319}
320
321static void
322cmu_print(register const u_char *bp, register u_int length)
323{
324	register const struct cmu_vend *cmu;
325	char *fmt = " %s:%s";
326
327#define PRINTCMUADDR(m, s) { TCHECK(cmu->m); \
328    if (cmu->m.s_addr != 0) \
329	printf(fmt, s, ipaddr_string(&cmu->m.s_addr)); }
330
331	printf(" vend-cmu");
332	cmu = (struct cmu_vend *)bp;
333
334	/* Only print if there are unknown bits */
335	TCHECK(cmu->v_flags);
336	if ((cmu->v_flags & ~(VF_SMASK)) != 0)
337		printf(" F:0x%x", cmu->v_flags);
338	PRINTCMUADDR(v_dgate, "DG");
339	PRINTCMUADDR(v_smask, cmu->v_flags & VF_SMASK ? "SM" : "SM*");
340	PRINTCMUADDR(v_dns1, "NS1");
341	PRINTCMUADDR(v_dns2, "NS2");
342	PRINTCMUADDR(v_ins1, "IEN1");
343	PRINTCMUADDR(v_ins2, "IEN2");
344	PRINTCMUADDR(v_ts1, "TS1");
345	PRINTCMUADDR(v_ts2, "TS2");
346	return;
347
348trunc:
349	fputs(tstr, stdout);
350#undef PRINTCMUADDR
351}
352