print-bootp.c revision 1.10 1 /*
2 * Copyright (c) 1988-1990 The Regents of the University of California.
3 * 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 * This file was copied from tcpdump-2.1.1 and modified.
24 * There is an e-mail list for tcpdump: <tcpdump (at) ee.lbl.gov>
25 */
26
27 #include <sys/cdefs.h>
28 #ifndef lint
29 __RCSID("$NetBSD: print-bootp.c,v 1.10 2009/04/15 00:23:29 lukem Exp $");
30 /* 93/10/10 <gwr (at) mc.com> New data-driven option print routine. */
31 #endif
32
33 #include <stdio.h>
34
35 #include <sys/param.h>
36 #include <sys/types.h>
37 #include <sys/socket.h>
38 #include <net/if.h>
39 #include <netinet/in.h>
40 #include <string.h>
41 #include <strings.h>
42 #include <ctype.h>
43
44 #include "bootp.h"
45 #include "bootptest.h"
46
47 /* These decode the vendor data. */
48 static void cmu_print(u_char *, int);
49 static void dump_hex(u_char *, int);
50 static void other_print(u_char *, int);
51 static void rfc1048_print(u_char *, int);
52
53 /*
54 * Print bootp requests
55 */
56 void
57 bootp_print(struct bootp *bp, int length, u_short sport, u_short dport)
58 {
59 static char tstr[] = " [|bootp]";
60 static unsigned char vm_cmu[4] = VM_CMU;
61 static unsigned char vm_rfc1048[4] = VM_RFC1048;
62 u_char *ep;
63 int vdlen;
64
65 #define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc
66
67 /* Note funny sized packets */
68 if (length != sizeof(struct bootp))
69 (void) printf(" [len=%d]", length);
70
71 /* 'ep' points to the end of avaible data. */
72 ep = (u_char *) snapend;
73
74 switch (bp->bp_op) {
75
76 case BOOTREQUEST:
77 /* Usually, a request goes from a client to a server */
78 if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
79 printf(" (request)");
80 break;
81
82 case BOOTREPLY:
83 /* Usually, a reply goes from a server to a client */
84 if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
85 printf(" (reply)");
86 break;
87
88 default:
89 printf(" bootp-#%d", bp->bp_op);
90 }
91
92 /* The usual hardware address type is 1 (10Mb Ethernet) */
93 if (bp->bp_htype != 1)
94 printf(" htype:%d", bp->bp_htype);
95
96 /* The usual length for 10Mb Ethernet address is 6 bytes */
97 if (bp->bp_hlen != 6)
98 printf(" hlen:%d", bp->bp_hlen);
99
100 /* Client's Hardware address */
101 if (bp->bp_hlen) {
102 struct ether_header *eh;
103 char *e;
104
105 TCHECK(bp->bp_chaddr[0], 6);
106 eh = (struct ether_header *) packetp;
107 if (bp->bp_op == BOOTREQUEST)
108 e = (char *) ESRC(eh);
109 else if (bp->bp_op == BOOTREPLY)
110 e = (char *) EDST(eh);
111 else
112 e = 0;
113 if (e == 0 || bcmp((char *) bp->bp_chaddr, e, 6))
114 dump_hex(bp->bp_chaddr, bp->bp_hlen);
115 }
116 /* Only print interesting fields */
117 if (bp->bp_hops)
118 printf(" hops:%d", bp->bp_hops);
119
120 if (bp->bp_xid)
121 printf(" xid:%d", ntohl(bp->bp_xid));
122
123 if (bp->bp_secs)
124 printf(" secs:%d", ntohs(bp->bp_secs));
125
126 /* Client's ip address */
127 TCHECK(bp->bp_ciaddr, sizeof(bp->bp_ciaddr));
128 if (bp->bp_ciaddr.s_addr)
129 printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
130
131 /* 'your' ip address (bootp client) */
132 TCHECK(bp->bp_yiaddr, sizeof(bp->bp_yiaddr));
133 if (bp->bp_yiaddr.s_addr)
134 printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
135
136 /* Server's ip address */
137 TCHECK(bp->bp_siaddr, sizeof(bp->bp_siaddr));
138 if (bp->bp_siaddr.s_addr)
139 printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
140
141 /* Gateway's ip address */
142 TCHECK(bp->bp_giaddr, sizeof(bp->bp_giaddr));
143 if (bp->bp_giaddr.s_addr)
144 printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
145
146 TCHECK(bp->bp_sname[0], sizeof(bp->bp_sname));
147 if (*bp->bp_sname) {
148 printf(" sname:");
149 if (printfn(bp->bp_sname, ep)) {
150 fputs(tstr + 1, stdout);
151 return;
152 }
153 }
154 TCHECK(bp->bp_file[0], sizeof(bp->bp_file));
155 if (*bp->bp_file) {
156 printf(" file:");
157 if (printfn(bp->bp_file, ep)) {
158 fputs(tstr + 1, stdout);
159 return;
160 }
161 }
162 /* Don't try to decode the vendor buffer unless we're verbose */
163 if (vflag <= 0)
164 return;
165
166 vdlen = sizeof(bp->bp_vend);
167 /* Vendor data can extend to the end of the packet. */
168 if (vdlen < (ep - bp->bp_vend))
169 vdlen = (ep - bp->bp_vend);
170
171 TCHECK(bp->bp_vend[0], vdlen);
172 printf(" vend");
173 if (!bcmp(bp->bp_vend, vm_rfc1048, sizeof(u_int32)))
174 rfc1048_print(bp->bp_vend, vdlen);
175 else if (!bcmp(bp->bp_vend, vm_cmu, sizeof(u_int32)))
176 cmu_print(bp->bp_vend, vdlen);
177 else
178 other_print(bp->bp_vend, vdlen);
179
180 return;
181 trunc:
182 fputs(tstr, stdout);
183 #undef TCHECK
184 }
185
186 /*
188 * Option description data follows.
189 * These are decribed in: RFC-1048, RFC-1395, RFC-1497, RFC-1533
190 *
191 * The first char of each option string encodes the data format:
192 * ?: unknown
193 * a: ASCII
194 * b: byte (8-bit)
195 * i: inet address
196 * l: int32
197 * s: short (16-bit)
198 */
199 const char *
200 rfc1048_opts[] = {
201 /* Originally from RFC-1048: */
202 "?PAD", /* 0: Padding - special, no data. */
203 "iSM", /* 1: subnet mask (RFC950)*/
204 "lTZ", /* 2: time offset, seconds from UTC */
205 "iGW", /* 3: gateways (or routers) */
206 "iTS", /* 4: time servers (RFC868) */
207 "iINS", /* 5: IEN name servers (IEN116) */
208 "iDNS", /* 6: domain name servers (RFC1035)(1034?) */
209 "iLOG", /* 7: MIT log servers */
210 "iCS", /* 8: cookie servers (RFC865) */
211 "iLPR", /* 9: lpr server (RFC1179) */
212 "iIPS", /* 10: impress servers (Imagen) */
213 "iRLP", /* 11: resource location servers (RFC887) */
214 "aHN", /* 12: host name (ASCII) */
215 "sBFS", /* 13: boot file size (in 512 byte blocks) */
216
217 /* Added by RFC-1395: */
218 "aDUMP", /* 14: Merit Dump File */
219 "aDNAM", /* 15: Domain Name (for DNS) */
220 "iSWAP", /* 16: Swap Server */
221 "aROOT", /* 17: Root Path */
222
223 /* Added by RFC-1497: */
224 "aEXTF", /* 18: Extensions Path (more options) */
225
226 /* Added by RFC-1533: (many, many options...) */
227 #if 1 /* These might not be worth recognizing by name. */
228
229 /* IP Layer Parameters, per-host (RFC-1533, sect. 4) */
230 "bIP-forward", /* 19: IP Forwarding flag */
231 "bIP-srcroute", /* 20: IP Source Routing Enable flag */
232 "iIP-filters", /* 21: IP Policy Filter (addr pairs) */
233 "sIP-maxudp", /* 22: IP Max-UDP reassembly size */
234 "bIP-ttlive", /* 23: IP Time to Live */
235 "lIP-pmtuage", /* 24: IP Path MTU aging timeout */
236 "sIP-pmtutab", /* 25: IP Path MTU plateau table */
237
238 /* IP parameters, per-interface (RFC-1533, sect. 5) */
239 "sIP-mtu-sz", /* 26: IP MTU size */
240 "bIP-mtu-sl", /* 27: IP MTU all subnets local */
241 "bIP-bcast1", /* 28: IP Broadcast Addr ones flag */
242 "bIP-mask-d", /* 29: IP do mask discovery */
243 "bIP-mask-s", /* 30: IP do mask supplier */
244 "bIP-rt-dsc", /* 31: IP do router discovery */
245 "iIP-rt-sa", /* 32: IP router solicitation addr */
246 "iIP-routes", /* 33: IP static routes (dst,router) */
247
248 /* Link Layer parameters, per-interface (RFC-1533, sect. 6) */
249 "bLL-trailer", /* 34: do tralier encapsulation */
250 "lLL-arp-tmo", /* 35: ARP cache timeout */
251 "bLL-ether2", /* 36: Ethernet version 2 (IEEE 802.3) */
252
253 /* TCP parameters (RFC-1533, sect. 7) */
254 "bTCP-def-ttl", /* 37: default time to live */
255 "lTCP-KA-tmo", /* 38: keepalive time interval */
256 "bTCP-KA-junk", /* 39: keepalive sends extra junk */
257
258 /* Application and Service Parameters (RFC-1533, sect. 8) */
259 "aNISDOM", /* 40: NIS Domain (Sun YP) */
260 "iNISSRV", /* 41: NIS Servers */
261 "iNTPSRV", /* 42: NTP (time) Servers (RFC 1129) */
262 "?VSINFO", /* 43: Vendor Specific Info (encapsulated) */
263 "iNBiosNS", /* 44: NetBIOS Name Server (RFC-1001,1..2) */
264 "iNBiosDD", /* 45: NetBIOS Datagram Dist. Server. */
265 "bNBiosNT", /* 46: NetBIOS Note Type */
266 "?NBiosS", /* 47: NetBIOS Scope */
267 "iXW-FS", /* 48: X Window System Font Servers */
268 "iXW-DM", /* 49: X Window System Display Managers */
269
270 /* DHCP extensions (RFC-1533, sect. 9) */
271 #endif
272 };
273 #define KNOWN_OPTIONS (sizeof(rfc1048_opts) / sizeof(rfc1048_opts[0]))
274
275 static void
276 rfc1048_print(u_char *bp, int length)
277 {
278 u_char tag;
279 u_char *ep;
280 int len;
281 u_int32 ul;
282 u_short us;
283 struct in_addr ia;
284 const char *optstr;
285
286 printf("-rfc1395");
287
288 /* Step over magic cookie */
289 bp += sizeof(int32);
290 /* Setup end pointer */
291 ep = bp + length;
292 while (bp < ep) {
293 tag = *bp++;
294 /* Check for tags with no data first. */
295 if (tag == TAG_PAD)
296 continue;
297 if (tag == TAG_END)
298 return;
299 if (tag < KNOWN_OPTIONS) {
300 optstr = rfc1048_opts[tag];
301 printf(" %s:", optstr + 1);
302 } else {
303 printf(" T%d:", tag);
304 optstr = "?";
305 }
306 /* Now scan the length byte. */
307 len = *bp++;
308 if (bp + len > ep) {
309 /* truncated option */
310 printf(" |(%d>%ld)", len, (long)(ep - bp));
311 return;
312 }
313 /* Print the option value(s). */
314 switch (optstr[0]) {
315
316 case 'a': /* ASCII string */
317 printfn(bp, bp + len);
318 bp += len;
319 len = 0;
320 break;
321
322 case 's': /* Word formats */
323 while (len >= 2) {
324 bcopy((char *) bp, (char *) &us, 2);
325 printf("%d", ntohs(us));
326 bp += 2;
327 len -= 2;
328 if (len) printf(",");
329 }
330 if (len) printf("(junk=%d)", len);
331 break;
332
333 case 'l': /* Long words */
334 while (len >= 4) {
335 bcopy((char *) bp, (char *) &ul, 4);
336 printf("%d", ntohl(ul));
337 bp += 4;
338 len -= 4;
339 if (len) printf(",");
340 }
341 if (len) printf("(junk=%d)", len);
342 break;
343
344 case 'i': /* INET addresses */
345 while (len >= 4) {
346 bcopy((char *) bp, (char *) &ia, 4);
347 printf("%s", ipaddr_string(&ia));
348 bp += 4;
349 len -= 4;
350 if (len) printf(",");
351 }
352 if (len) printf("(junk=%d)", len);
353 break;
354
355 case 'b':
356 default:
357 break;
358
359 } /* switch */
360
361 /* Print as characters, if appropriate. */
362 if (len) {
363 dump_hex(bp, len);
364 if (isascii(*bp) && isprint(*bp)) {
365 printf("(");
366 printfn(bp, bp + len);
367 printf(")");
368 }
369 bp += len;
370 len = 0;
371 }
372 } /* while bp < ep */
373 }
374
375 static void
376 cmu_print(u_char *bp, int length)
377 {
378 struct cmu_vend *v;
379 u_char *ep;
380
381 printf("-cmu");
382
383 v = (struct cmu_vend *) bp;
384 if (length < (int)sizeof(*v)) {
385 printf(" |L=%d", length);
386 return;
387 }
388 /* Setup end pointer */
389 ep = bp + length;
390
391 /* Subnet mask */
392 if (v->v_flags & VF_SMASK) {
393 printf(" SM:%s", ipaddr_string(&v->v_smask));
394 }
395 /* Default gateway */
396 if (v->v_dgate.s_addr)
397 printf(" GW:%s", ipaddr_string(&v->v_dgate));
398
399 /* Domain name servers */
400 if (v->v_dns1.s_addr)
401 printf(" DNS1:%s", ipaddr_string(&v->v_dns1));
402 if (v->v_dns2.s_addr)
403 printf(" DNS2:%s", ipaddr_string(&v->v_dns2));
404
405 /* IEN-116 name servers */
406 if (v->v_ins1.s_addr)
407 printf(" INS1:%s", ipaddr_string(&v->v_ins1));
408 if (v->v_ins2.s_addr)
409 printf(" INS2:%s", ipaddr_string(&v->v_ins2));
410
411 /* Time servers */
412 if (v->v_ts1.s_addr)
413 printf(" TS1:%s", ipaddr_string(&v->v_ts1));
414 if (v->v_ts2.s_addr)
415 printf(" TS2:%s", ipaddr_string(&v->v_ts2));
416
417 }
418
419
420 /*
421 * Print out arbitrary, unknown vendor data.
422 */
423
424 static void
425 other_print(u_char *bp, int length)
426 {
427 u_char *ep; /* end pointer */
428 u_char *zp; /* points one past last non-zero byte */
429
430 /* Setup end pointer */
431 ep = bp + length;
432
433 /* Find the last non-zero byte. */
434 for (zp = ep; zp > bp; zp--) {
435 if (zp[-1] != 0)
436 break;
437 }
438
439 /* Print the all-zero case in a compact representation. */
440 if (zp == bp) {
441 printf("-all-zero");
442 return;
443 }
444 printf("-unknown");
445
446 /* Are there enough trailing zeros to make "00..." worthwhile? */
447 if (zp + 2 > ep)
448 zp = ep; /* print them all normally */
449
450 /* Now just print all the non-zero data. */
451 while (bp < zp) {
452 printf(".%02X", *bp);
453 bp++;
454 }
455
456 if (zp < ep)
457 printf(".00...");
458
459 return;
460 }
461
462 static void
463 dump_hex(u_char *bp, int len)
464 {
465 while (len > 0) {
466 printf("%02X", *bp);
467 bp++;
468 len--;
469 if (len) printf(".");
470 }
471 }
472
473 /*
474 * Local Variables:
475 * tab-width: 4
476 * c-indent-level: 4
477 * c-argdecl-indent: 4
478 * c-continued-statement-offset: 4
479 * c-continued-brace-offset: -4
480 * c-label-offset: -4
481 * c-brace-offset: 0
482 * End:
483 */
484