print-bootp.c revision 1.4 
1/*	$OpenBSD: print-bootp.c,v 1.4 1996/07/13 11:01:16 mickey Exp $	*/
2
3/*
4 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996
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 * Format and print bootp packets.
24 */
25#ifndef lint
26static char rcsid[] =
27    "@(#) Header: print-bootp.c,v 1.38 96/06/23 02:11:45 leres Exp (LBL)";
28#endif
29
30#include <sys/param.h>
31#include <sys/time.h>
32#include <sys/types.h>
33#include <sys/socket.h>
34
35#if __STDC__
36struct mbuf;
37struct rtentry;
38#endif
39#include <net/if.h>
40
41#include <netinet/in.h>
42#include <netinet/if_ether.h>
43
44#include <ctype.h>
45#include <stdio.h>
46#include <string.h>
47
48#include "interface.h"
49#include "addrtoname.h"
50#include "bootp.h"
51
52static void rfc1048_print(const u_char *, int);
53static void cmu_print(const u_char *, int);
54
55static char tstr[] = " [|bootp]";
56
57/*
58 * Print bootp requests
59 */
60void
61bootp_print(register const u_char *cp, int length,
62	    u_short sport, u_short dport)
63{
64	register const struct bootp *bp;
65	static u_char vm_cmu[4] = VM_CMU;
66	static u_char vm_rfc1048[4] = VM_RFC1048;
67	const u_char *ep;
68
69#define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc
70
71	bp = (struct bootp *)cp;
72	/* 'ep' points to the end of available data. */
73	ep = snapend;
74
75	TCHECK(bp->bp_op, sizeof(bp->bp_op));
76	switch (bp->bp_op) {
77
78	case BOOTREQUEST:
79		/* Usually, a request goes from a client to a server */
80		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
81			printf(" (request)");
82		break;
83
84	case BOOTREPLY:
85		/* Usually, a reply goes from a server to a client */
86		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
87			printf(" (reply)");
88		break;
89
90	default:
91		printf(" bootp-#%d", bp->bp_op);
92	}
93
94	TCHECK(bp->bp_secs, sizeof(bp->bp_secs));
95
96	/* The usual hardware address type is 1 (10Mb Ethernet) */
97	if (bp->bp_htype != 1)
98		printf(" htype-#%d", bp->bp_htype);
99
100	/* The usual length for 10Mb Ethernet address is 6 bytes */
101	if (bp->bp_htype != 1 || bp->bp_hlen != 6)
102		printf(" hlen:%d", bp->bp_hlen);
103
104	/* Only print interesting fields */
105	if (bp->bp_hops)
106		printf(" hops:%d", bp->bp_hops);
107	if (bp->bp_xid)
108		printf(" xid:0x%x", (u_int32_t)ntohl(bp->bp_xid));
109	if (bp->bp_secs)
110		printf(" secs:%d", ntohs(bp->bp_secs));
111
112	/* Client's ip address */
113	TCHECK(bp->bp_ciaddr, sizeof(bp->bp_ciaddr));
114	if (bp->bp_ciaddr.s_addr)
115		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
116
117	/* 'your' ip address (bootp client) */
118	TCHECK(bp->bp_yiaddr, sizeof(bp->bp_yiaddr));
119	if (bp->bp_yiaddr.s_addr)
120		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
121
122	/* Server's ip address */
123	TCHECK(bp->bp_siaddr, sizeof(bp->bp_siaddr));
124	if (bp->bp_siaddr.s_addr)
125		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
126
127	/* Gateway's ip address */
128	TCHECK(bp->bp_giaddr, sizeof(bp->bp_giaddr));
129	if (bp->bp_giaddr.s_addr)
130		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
131
132	/* Client's Ethernet address */
133	if (bp->bp_htype == 1 && bp->bp_hlen == 6) {
134		register const struct ether_header *eh;
135		register const char *e;
136
137		TCHECK(bp->bp_chaddr[0], 6);
138		eh = (struct ether_header *)packetp;
139		if (bp->bp_op == BOOTREQUEST)
140			e = (const char *)ESRC(eh);
141		else if (bp->bp_op == BOOTREPLY)
142			e = (const char *)EDST(eh);
143		else
144			e = 0;
145		if (e == 0 || memcmp((char *)bp->bp_chaddr, e, 6) != 0)
146			printf(" ether %s", etheraddr_string(bp->bp_chaddr));
147	}
148
149	TCHECK(bp->bp_sname[0], 1);		/* check first char only */
150	if (*bp->bp_sname) {
151		printf(" sname ");
152		if (fn_print(bp->bp_sname, ep)) {
153			fputs(tstr + 1, stdout);
154			return;
155		}
156	}
157	TCHECK(bp->bp_sname[0], 1);		/* check first char only */
158	if (*bp->bp_file) {
159		printf(" file ");
160		if (fn_print(bp->bp_file, ep)) {
161			fputs(tstr + 1, stdout);
162			return;
163		}
164	}
165
166	/* Decode the vendor buffer */
167	TCHECK(bp->bp_vend[0], sizeof(bp->bp_vend));
168	length -= sizeof(*bp) - sizeof(bp->bp_vend);
169	if (memcmp((char *)bp->bp_vend, (char *)vm_rfc1048,
170		 sizeof(u_int32_t)) == 0)
171		rfc1048_print(bp->bp_vend, length);
172	else if (memcmp((char *)bp->bp_vend, (char *)vm_cmu,
173		      sizeof(u_int32_t)) == 0)
174		cmu_print(bp->bp_vend, length);
175	else {
176		u_int32_t ul;
177
178		memcpy((char *)&ul, (char *)bp->bp_vend, sizeof(ul));
179		if (ul != 0)
180			printf("vend-#0x%x", ul);
181	}
182
183	return;
184trunc:
185	fputs(tstr, stdout);
186#undef TCHECK
187}
188
189/* The first character specifies the format to print */
190static struct tok tag2str[] = {
191/* RFC1048 tags */
192	{ TAG_PAD,		" PAD" },
193	{ TAG_SUBNET_MASK,	"iSM" },	/* subnet mask (RFC950) */
194	{ TAG_TIME_OFFSET,	"lTZ" },	/* seconds from UTC */
195	{ TAG_GATEWAY,		"iDG" },	/* default gateway */
196	{ TAG_TIME_SERVER,	"iTS" },	/* time servers (RFC868) */
197	{ TAG_NAME_SERVER,	"iIEN" },	/* IEN name servers (IEN116) */
198	{ TAG_DOMAIN_SERVER,	"iNS" },	/* domain name (RFC1035) */
199	{ TAG_LOG_SERVER,	"iLOG" },	/* MIT log servers */
200	{ TAG_COOKIE_SERVER,	"iCS" },	/* cookie servers (RFC865) */
201	{ TAG_LPR_SERVER,	"iLPR" },	/* lpr server (RFC1179) */
202	{ TAG_IMPRESS_SERVER,	"iIM" },	/* impress servers (Imagen) */
203	{ TAG_RLP_SERVER,	"iRL" },	/* resource location (RFC887) */
204	{ TAG_HOSTNAME,		"aHN" },	/* ascii hostname */
205	{ TAG_BOOTSIZE,		"sBS" },	/* 512 byte blocks */
206	{ TAG_END,		" END" },
207/* RFC1497 tags */
208	{ TAG_DUMPPATH,		"aDP" },
209	{ TAG_DOMAINNAME,	"aDN" },
210	{ TAG_SWAP_SERVER,	"iSS" },
211	{ TAG_ROOTPATH,		"aRP" },
212	{ TAG_EXTPATH,		"aEP" },
213	{ 0,			NULL }
214};
215
216static void
217rfc1048_print(register const u_char *bp, register int length)
218{
219	register u_char tag;
220	register const u_char *ep;
221	register u_int len, size;
222	register const char *cp;
223	register char c;
224	int first;
225	u_int32_t ul;
226	u_short us;
227
228	printf(" vend-rfc1048");
229
230	/* Setup end pointer */
231	ep = bp + length;
232
233	/* Step over magic cookie */
234	bp += sizeof(int32_t);
235
236	/* Loop while we there is a tag left in the buffer */
237	while (bp + 1 < ep) {
238		tag = *bp++;
239		if (tag == TAG_PAD)
240			continue;
241		if (tag == TAG_END)
242			return;
243		cp = tok2str(tag2str, "?T%d", tag);
244		c = *cp++;
245		printf(" %s:", cp);
246
247		/* Get the length; check for truncation */
248		if (bp + 1 >= ep) {
249			fputs(tstr, stdout);
250			return;
251		}
252		len = *bp++;
253		if (bp + len >= ep) {
254			fputs(tstr, stdout);
255			return;
256		}
257
258		/* Print data */
259		size = len;
260		if (c == '?') {
261			/* Base default formats for unknown tags on data size */
262			if (size & 1)
263				c = 'b';
264			else if (size & 2)
265				c = 's';
266			else
267				c = 'l';
268		}
269		first = 1;
270		switch (c) {
271
272		case 'a':
273			/* ascii strings */
274			(void)fn_printn(bp, size, NULL);
275			bp += size;
276			size = 0;
277			break;
278
279		case 'i':
280		case 'l':
281			/* ip addresses/32-bit words */
282			while (size >= sizeof(ul)) {
283				if (!first)
284					putchar(',');
285				memcpy((char *)&ul, (char *)bp, sizeof(ul));
286				if (c == 'i')
287					printf("%s", ipaddr_string(&ul));
288				else
289					printf("%u", ul);
290				bp += sizeof(ul);
291				size -= sizeof(ul);
292				first = 0;
293			}
294			break;
295
296		case 's':
297			/* shorts */
298			while (size >= sizeof(us)) {
299				if (!first)
300					putchar(',');
301				memcpy((char *)&us, (char *)bp, sizeof(us));
302				printf("%d", us);
303				bp += sizeof(us);
304				size -= sizeof(us);
305				first = 0;
306			}
307			break;
308
309		case 'b':
310		default:
311			/* Bytes */
312			while (size > 0) {
313				if (!first)
314					putchar('.');
315				printf("%d", *bp);
316				++bp;
317				--size;
318				first = 0;
319			}
320			break;
321		}
322		/* Data left over? */
323		if (size)
324			printf("[len %d]", len);
325	}
326}
327
328static void
329cmu_print(register const u_char *bp, register int length)
330{
331	register const struct cmu_vend *cmu;
332	register const u_char *ep;
333	char *fmt = " %s:%s";
334
335#define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc
336#define PRINTCMUADDR(m, s) { TCHECK(cmu->m, sizeof(cmu->m)); \
337    if (cmu->m.s_addr != 0) \
338	printf(fmt, s, ipaddr_string(&cmu->m.s_addr)); }
339
340	/* Setup end pointer */
341	ep = bp + length;
342
343	printf(" vend-cmu");
344	cmu = (struct cmu_vend *)bp;
345
346	/* Only print if there are unknown bits */
347	TCHECK(cmu->v_flags, sizeof(cmu->v_flags));
348	if ((cmu->v_flags & ~(VF_SMASK)) != 0)
349		printf(" F:0x%x", cmu->v_flags);
350	PRINTCMUADDR(v_dgate, "DG");
351	PRINTCMUADDR(v_smask, cmu->v_flags & VF_SMASK ? "SM" : "SM*");
352	PRINTCMUADDR(v_dns1, "NS1");
353	PRINTCMUADDR(v_dns2, "NS2");
354	PRINTCMUADDR(v_ins1, "IEN1");
355	PRINTCMUADDR(v_ins2, "IEN2");
356	PRINTCMUADDR(v_ts1, "TS1");
357	PRINTCMUADDR(v_ts2, "TS2");
358	return;
359
360trunc:
361	fputs(tstr, stdout);
362#undef TCHECK
363#undef PRINTCMUADDR
364}
365