xref: /freebsd/contrib/tcpdump/print-bootp.c (revision 4cf49a43559ed9fdad601bdcccd2c55963008675)
1 /*
2  * Copyright (c) 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  * Format and print bootp packets.
22  */
23 #ifndef lint
24 static const char rcsid[] =
25     "@(#) $Header: print-bootp.c,v 1.46 98/07/18 13:33:58 leres Exp $ (LBL)";
26 #endif
27 
28 #include <sys/param.h>
29 #include <sys/time.h>
30 #include <sys/socket.h>
31 
32 #if __STDC__
33 struct mbuf;
34 struct rtentry;
35 #endif
36 #include <net/if.h>
37 
38 #include <netinet/in.h>
39 #include <net/ethernet.h>
40 
41 #include <ctype.h>
42 #ifdef HAVE_MEMORY_H
43 #include <memory.h>
44 #endif
45 #include <stdio.h>
46 #include <string.h>
47 
48 #include "interface.h"
49 #include "addrtoname.h"
50 #include "bootp.h"
51 
52 static void rfc1048_print(const u_char *, u_int);
53 static void cmu_print(const u_char *, u_int);
54 
55 static char tstr[] = " [|bootp]";
56 
57 /*
58  * Print bootp requests
59  */
60 void
61 bootp_print(register const u_char *cp, u_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 
68 	bp = (struct bootp *)cp;
69 	TCHECK(bp->bp_op);
70 	switch (bp->bp_op) {
71 
72 	case BOOTREQUEST:
73 		/* Usually, a request goes from a client to a server */
74 		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
75 			printf(" (request)");
76 		break;
77 
78 	case BOOTREPLY:
79 		/* Usually, a reply goes from a server to a client */
80 		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
81 			printf(" (reply)");
82 		break;
83 
84 	default:
85 		printf(" bootp-#%d", bp->bp_op);
86 	}
87 
88 	TCHECK(bp->bp_secs);
89 
90 	/* The usual hardware address type is 1 (10Mb Ethernet) */
91 	if (bp->bp_htype != 1)
92 		printf(" htype-#%d", bp->bp_htype);
93 
94 	/* The usual length for 10Mb Ethernet address is 6 bytes */
95 	if (bp->bp_htype != 1 || bp->bp_hlen != 6)
96 		printf(" hlen:%d", bp->bp_hlen);
97 
98 	/* Only print interesting fields */
99 	if (bp->bp_hops)
100 		printf(" hops:%d", bp->bp_hops);
101 	if (bp->bp_xid)
102 		printf(" xid:0x%x", (u_int32_t)ntohl(bp->bp_xid));
103 	if (bp->bp_secs)
104 		printf(" secs:%d", ntohs(bp->bp_secs));
105 
106 	/* Client's ip address */
107 	TCHECK(bp->bp_ciaddr);
108 	if (bp->bp_ciaddr.s_addr)
109 		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
110 
111 	/* 'your' ip address (bootp client) */
112 	TCHECK(bp->bp_yiaddr);
113 	if (bp->bp_yiaddr.s_addr)
114 		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
115 
116 	/* Server's ip address */
117 	TCHECK(bp->bp_siaddr);
118 	if (bp->bp_siaddr.s_addr)
119 		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
120 
121 	/* Gateway's ip address */
122 	TCHECK(bp->bp_giaddr);
123 	if (bp->bp_giaddr.s_addr)
124 		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
125 
126 	/* Client's Ethernet address */
127 	if (bp->bp_htype == 1 && bp->bp_hlen == 6) {
128 		register const struct ether_header *eh;
129 		register const char *e;
130 
131 		TCHECK2(bp->bp_chaddr[0], 6);
132 		eh = (struct ether_header *)packetp;
133 		if (bp->bp_op == BOOTREQUEST)
134 			e = (const char *)ESRC(eh);
135 		else if (bp->bp_op == BOOTREPLY)
136 			e = (const char *)EDST(eh);
137 		else
138 			e = 0;
139 		if (e == 0 || memcmp((char *)bp->bp_chaddr, e, 6) != 0)
140 			printf(" ether %s", etheraddr_string(bp->bp_chaddr));
141 	}
142 
143 	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
144 	if (*bp->bp_sname) {
145 		printf(" sname \"");
146 		if (fn_print(bp->bp_sname, snapend)) {
147 			putchar('"');
148 			fputs(tstr + 1, stdout);
149 			return;
150 		}
151 		putchar('"');
152 	}
153 	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
154 	if (*bp->bp_file) {
155 		printf(" file \"");
156 		if (fn_print(bp->bp_file, snapend)) {
157 			putchar('"');
158 			fputs(tstr + 1, stdout);
159 			return;
160 		}
161 		putchar('"');
162 	}
163 
164 	/* Decode the vendor buffer */
165 	TCHECK(bp->bp_vend[0]);
166 	length -= sizeof(*bp) - sizeof(bp->bp_vend);
167 	if (memcmp((char *)bp->bp_vend, (char *)vm_rfc1048,
168 		 sizeof(u_int32_t)) == 0)
169 		rfc1048_print(bp->bp_vend, length);
170 	else if (memcmp((char *)bp->bp_vend, (char *)vm_cmu,
171 		      sizeof(u_int32_t)) == 0)
172 		cmu_print(bp->bp_vend, length);
173 	else {
174 		u_int32_t ul;
175 
176 		memcpy((char *)&ul, (char *)bp->bp_vend, sizeof(ul));
177 		if (ul != 0)
178 			printf("vend-#0x%x", ul);
179 	}
180 
181 	return;
182 trunc:
183 	fputs(tstr, stdout);
184 }
185 
186 /* The first character specifies the format to print */
187 static struct tok tag2str[] = {
188 /* RFC1048 tags */
189 	{ TAG_PAD,		" PAD" },
190 	{ TAG_SUBNET_MASK,	"iSM" },	/* subnet mask (RFC950) */
191 	{ TAG_TIME_OFFSET,	"lTZ" },	/* seconds from UTC */
192 	{ TAG_GATEWAY,		"iDG" },	/* default gateway */
193 	{ TAG_TIME_SERVER,	"iTS" },	/* time servers (RFC868) */
194 	{ TAG_NAME_SERVER,	"iIEN" },	/* IEN name servers (IEN116) */
195 	{ TAG_DOMAIN_SERVER,	"iNS" },	/* domain name (RFC1035) */
196 	{ TAG_LOG_SERVER,	"iLOG" },	/* MIT log servers */
197 	{ TAG_COOKIE_SERVER,	"iCS" },	/* cookie servers (RFC865) */
198 	{ TAG_LPR_SERVER,	"iLPR" },	/* lpr server (RFC1179) */
199 	{ TAG_IMPRESS_SERVER,	"iIM" },	/* impress servers (Imagen) */
200 	{ TAG_RLP_SERVER,	"iRL" },	/* resource location (RFC887) */
201 	{ TAG_HOSTNAME,		"aHN" },	/* ascii hostname */
202 	{ TAG_BOOTSIZE,		"sBS" },	/* 512 byte blocks */
203 	{ TAG_END,		" END" },
204 /* RFC1497 tags */
205 	{ TAG_DUMPPATH,		"aDP" },
206 	{ TAG_DOMAINNAME,	"aDN" },
207 	{ TAG_SWAP_SERVER,	"iSS" },
208 	{ TAG_ROOTPATH,		"aRP" },
209 	{ TAG_EXTPATH,		"aEP" },
210 	{ 0,			NULL }
211 };
212 
213 static void
214 rfc1048_print(register const u_char *bp, register u_int length)
215 {
216 	register u_char tag;
217 	register u_int len, size;
218 	register const char *cp;
219 	register char c;
220 	int first;
221 	u_int32_t ul;
222 	u_short us;
223 
224 	printf(" vend-rfc1048");
225 
226 	/* Step over magic cookie */
227 	bp += sizeof(int32_t);
228 
229 	/* Loop while we there is a tag left in the buffer */
230 	while (bp + 1 < snapend) {
231 		tag = *bp++;
232 		if (tag == TAG_PAD)
233 			continue;
234 		if (tag == TAG_END)
235 			return;
236 		cp = tok2str(tag2str, "?T%d", tag);
237 		c = *cp++;
238 		printf(" %s:", cp);
239 
240 		/* Get the length; check for truncation */
241 		if (bp + 1 >= snapend) {
242 			fputs(tstr, stdout);
243 			return;
244 		}
245 		len = *bp++;
246 		if (bp + len >= snapend) {
247 			fputs(tstr, stdout);
248 			return;
249 		}
250 
251 		/* Print data */
252 		size = len;
253 		if (c == '?') {
254 			/* Base default formats for unknown tags on data size */
255 			if (size & 1)
256 				c = 'b';
257 			else if (size & 2)
258 				c = 's';
259 			else
260 				c = 'l';
261 		}
262 		first = 1;
263 		switch (c) {
264 
265 		case 'a':
266 			/* ascii strings */
267 			putchar('"');
268 			(void)fn_printn(bp, size, NULL);
269 			putchar('"');
270 			bp += size;
271 			size = 0;
272 			break;
273 
274 		case 'i':
275 		case 'l':
276 			/* ip addresses/32-bit words */
277 			while (size >= sizeof(ul)) {
278 				if (!first)
279 					putchar(',');
280 				memcpy((char *)&ul, (char *)bp, sizeof(ul));
281 				if (c == 'i')
282 					printf("%s", ipaddr_string(&ul));
283 				else
284 					printf("%u", ul);
285 				bp += sizeof(ul);
286 				size -= sizeof(ul);
287 				first = 0;
288 			}
289 			break;
290 
291 		case 's':
292 			/* shorts */
293 			while (size >= sizeof(us)) {
294 				if (!first)
295 					putchar(',');
296 				memcpy((char *)&us, (char *)bp, sizeof(us));
297 				printf("%d", us);
298 				bp += sizeof(us);
299 				size -= sizeof(us);
300 				first = 0;
301 			}
302 			break;
303 
304 		case 'b':
305 		default:
306 			/* Bytes */
307 			while (size > 0) {
308 				if (!first)
309 					putchar('.');
310 				printf("%d", *bp);
311 				++bp;
312 				--size;
313 				first = 0;
314 			}
315 			break;
316 		}
317 		/* Data left over? */
318 		if (size)
319 			printf("[len %d]", len);
320 	}
321 }
322 
323 static void
324 cmu_print(register const u_char *bp, register u_int length)
325 {
326 	register const struct cmu_vend *cmu;
327 	char *fmt = " %s:%s";
328 
329 #define PRINTCMUADDR(m, s) { TCHECK(cmu->m); \
330     if (cmu->m.s_addr != 0) \
331 	printf(fmt, s, ipaddr_string(&cmu->m.s_addr)); }
332 
333 	printf(" vend-cmu");
334 	cmu = (struct cmu_vend *)bp;
335 
336 	/* Only print if there are unknown bits */
337 	TCHECK(cmu->v_flags);
338 	if ((cmu->v_flags & ~(VF_SMASK)) != 0)
339 		printf(" F:0x%x", cmu->v_flags);
340 	PRINTCMUADDR(v_dgate, "DG");
341 	PRINTCMUADDR(v_smask, cmu->v_flags & VF_SMASK ? "SM" : "SM*");
342 	PRINTCMUADDR(v_dns1, "NS1");
343 	PRINTCMUADDR(v_dns2, "NS2");
344 	PRINTCMUADDR(v_ins1, "IEN1");
345 	PRINTCMUADDR(v_ins2, "IEN2");
346 	PRINTCMUADDR(v_ts1, "TS1");
347 	PRINTCMUADDR(v_ts2, "TS2");
348 	return;
349 
350 trunc:
351 	fputs(tstr, stdout);
352 #undef PRINTCMUADDR
353 }
354