Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1988-1990
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that:
 * 1. Source code distributions retain the above copyright
 *    notice and this paragraph in its entirety
 * 2. Distributions including binary code include the above copyright
 *    notice and this paragraph in its entirety in the documentation
 *    or other materials provided with the distribution, and 
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 *
 * Format and print bootp packets.
 *
 * This file was copied from tcpdump-2.1.1 and modified.
 * There is an e-mail list for tcpdump: <tcpdump@ee.lbl.gov>
 *
 * $FreeBSD$
 */

#include <stdio.h>

#include <sys/param.h>
#include <sys/types.h>
#include <sys/socket.h>

#include <sys/time.h>	/* for struct timeval in net/if.h */
#include <net/if.h>
#include <netinet/in.h>

#include <string.h>
#include <ctype.h>

#include "bootp.h"
#include "bootptest.h"

/* These decode the vendor data. */
static void rfc1048_print(u_char *bp, int length);
static void cmu_print(u_char *bp, int length);
static void other_print(u_char *bp, int length);
static void dump_hex(u_char *bp, int len);

/*
 * Print bootp requests
 */
void
bootp_print(bp, length, sport, dport)
	struct bootp *bp;
	int length;
	u_short sport, dport;
{
	static char tstr[] = " [|bootp]";
	static unsigned char vm_cmu[4] = VM_CMU;
	static unsigned char vm_rfc1048[4] = VM_RFC1048;
	u_char *ep;
	int vdlen;

#define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc

	/* Note funny sized packets */
	if (length != sizeof(struct bootp))
		(void) printf(" [len=%d]", length);

	/* 'ep' points to the end of avaible data. */
	ep = (u_char *) snapend;

	switch (bp->bp_op) {

	case BOOTREQUEST:
		/* Usually, a request goes from a client to a server */
		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
			printf(" (request)");
		break;

	case BOOTREPLY:
		/* Usually, a reply goes from a server to a client */
		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
			printf(" (reply)");
		break;

	default:
		printf(" bootp-#%d", bp->bp_op);
	}

	/* The usual hardware address type is 1 (10Mb Ethernet) */
	if (bp->bp_htype != 1)
		printf(" htype:%d", bp->bp_htype);

	/* The usual length for 10Mb Ethernet address is 6 bytes */
	if (bp->bp_hlen != 6)
		printf(" hlen:%d", bp->bp_hlen);

	/* Client's Hardware address */
	if (bp->bp_hlen) {
		struct ether_header *eh;
		char *e;

		TCHECK(bp->bp_chaddr[0], 6);
		eh = (struct ether_header *) packetp;
		if (bp->bp_op == BOOTREQUEST)
			e = (char *) ESRC(eh);
		else if (bp->bp_op == BOOTREPLY)
			e = (char *) EDST(eh);
		else
			e = NULL;
		if (e == NULL || bcmp((char *) bp->bp_chaddr, e, 6))
			dump_hex(bp->bp_chaddr, bp->bp_hlen);
	}
	/* Only print interesting fields */
	if (bp->bp_hops)
		printf(" hops:%d", bp->bp_hops);

	if (bp->bp_xid)
		printf(" xid:%ld", (long)ntohl(bp->bp_xid));

	if (bp->bp_secs)
		printf(" secs:%d", ntohs(bp->bp_secs));

	/* Client's ip address */
	TCHECK(bp->bp_ciaddr, sizeof(bp->bp_ciaddr));
	if (bp->bp_ciaddr.s_addr)
		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));

	/* 'your' ip address (bootp client) */
	TCHECK(bp->bp_yiaddr, sizeof(bp->bp_yiaddr));
	if (bp->bp_yiaddr.s_addr)
		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));

	/* Server's ip address */
	TCHECK(bp->bp_siaddr, sizeof(bp->bp_siaddr));
	if (bp->bp_siaddr.s_addr)
		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));

	/* Gateway's ip address */
	TCHECK(bp->bp_giaddr, sizeof(bp->bp_giaddr));
	if (bp->bp_giaddr.s_addr)
		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));

	TCHECK(bp->bp_sname[0], sizeof(bp->bp_sname));
	if (*bp->bp_sname) {
		printf(" sname:");
		if (printfn(bp->bp_sname, ep)) {
			fputs(tstr + 1, stdout);
			return;
		}
	}
	TCHECK(bp->bp_file[0], sizeof(bp->bp_file));
	if (*bp->bp_file) {
		printf(" file:");
		if (printfn(bp->bp_file, ep)) {
			fputs(tstr + 1, stdout);
			return;
		}
	}
	/* Don't try to decode the vendor buffer unless we're verbose */
	if (vflag <= 0)
		return;

	vdlen = sizeof(bp->bp_vend);
	/* Vendor data can extend to the end of the packet. */
	if (vdlen < (ep - bp->bp_vend))
		vdlen = (ep - bp->bp_vend);

	TCHECK(bp->bp_vend[0], vdlen);
	printf(" vend");
	if (!bcmp(bp->bp_vend, vm_rfc1048, sizeof(u_int32)))
		rfc1048_print(bp->bp_vend, vdlen);
	else if (!bcmp(bp->bp_vend, vm_cmu, sizeof(u_int32)))
		cmu_print(bp->bp_vend, vdlen);
	else
		other_print(bp->bp_vend, vdlen);

	return;
 trunc:
	fputs(tstr, stdout);
#undef TCHECK
}

/*
 * Option description data follows.
 * These are described in: RFC-1048, RFC-1395, RFC-1497, RFC-1533
 *
 * The first char of each option string encodes the data format:
 * ?: unknown
 * a: ASCII
 * b: byte (8-bit)
 * i: inet address
 * l: int32
 * s: short (16-bit)
 */
char *
rfc1048_opts[] = {
	/* Originally from RFC-1048: */
	"?PAD",				/*  0: Padding - special, no data. */
	"iSM",				/*  1: subnet mask (RFC950)*/
	"lTZ",				/*  2: time offset, seconds from UTC */
	"iGW",				/*  3: gateways (or routers) */
	"iTS",				/*  4: time servers (RFC868) */
	"iINS",				/*  5: IEN name servers (IEN116) */
	"iDNS",				/*  6: domain name servers (RFC1035)(1034?) */
	"iLOG",				/*  7: MIT log servers */
	"iCS",				/*  8: cookie servers (RFC865) */
	"iLPR",				/*  9: lpr server (RFC1179) */
	"iIPS",				/* 10: impress servers (Imagen) */
	"iRLP",				/* 11: resource location servers (RFC887) */
	"aHN",				/* 12: host name (ASCII) */
	"sBFS",				/* 13: boot file size (in 512 byte blocks) */

	/* Added by RFC-1395: */
	"aDUMP",			/* 14: Merit Dump File */
	"aDNAM",			/* 15: Domain Name (for DNS) */
	"iSWAP",			/* 16: Swap Server */
	"aROOT",			/* 17: Root Path */

	/* Added by RFC-1497: */
	"aEXTF",			/* 18: Extensions Path (more options) */

	/* Added by RFC-1533: (many, many options...) */
#if 1	/* These might not be worth recognizing by name. */

	/* IP Layer Parameters, per-host (RFC-1533, sect. 4) */
	"bIP-forward",		/* 19: IP Forwarding flag */
	"bIP-srcroute",		/* 20: IP Source Routing Enable flag */
	"iIP-filters",		/* 21: IP Policy Filter (addr pairs) */
	"sIP-maxudp",		/* 22: IP Max-UDP reassembly size */
	"bIP-ttlive",		/* 23: IP Time to Live */
	"lIP-pmtuage",		/* 24: IP Path MTU aging timeout */
	"sIP-pmtutab",		/* 25: IP Path MTU plateau table */

	/* IP parameters, per-interface (RFC-1533, sect. 5) */
	"sIP-mtu-sz",		/* 26: IP MTU size */
	"bIP-mtu-sl",		/* 27: IP MTU all subnets local */
	"bIP-bcast1",		/* 28: IP Broadcast Addr ones flag */
	"bIP-mask-d",		/* 29: IP do mask discovery */
	"bIP-mask-s",		/* 30: IP do mask supplier */
	"bIP-rt-dsc",		/* 31: IP do router discovery */
	"iIP-rt-sa",		/* 32: IP router solicitation addr */
	"iIP-routes",		/* 33: IP static routes (dst,router) */

	/* Link Layer parameters, per-interface (RFC-1533, sect. 6) */
	"bLL-trailer",		/* 34: do tralier encapsulation */
	"lLL-arp-tmo",		/* 35: ARP cache timeout */
	"bLL-ether2",		/* 36: Ethernet version 2 (IEEE 802.3) */

	/* TCP parameters (RFC-1533, sect. 7) */
	"bTCP-def-ttl",		/* 37: default time to live */
	"lTCP-KA-tmo",		/* 38: keepalive time interval */
	"bTCP-KA-junk",		/* 39: keepalive sends extra junk */

	/* Application and Service Parameters (RFC-1533, sect. 8) */
	"aNISDOM",			/* 40: NIS Domain (Sun YP) */
	"iNISSRV",			/* 41: NIS Servers */
	"iNTPSRV",			/* 42: NTP (time) Servers (RFC 1129) */
	"?VSINFO",			/* 43: Vendor Specific Info (encapsulated) */
	"iNBiosNS",			/* 44: NetBIOS Name Server (RFC-1001,1..2) */
	"iNBiosDD",			/* 45: NetBIOS Datagram Dist. Server. */
	"bNBiosNT",			/* 46: NetBIOS Note Type */
	"?NBiosS",			/* 47: NetBIOS Scope */
	"iXW-FS",			/* 48: X Window System Font Servers */
	"iXW-DM",			/* 49: X Window System Display Managers */

	/* DHCP extensions (RFC-1533, sect. 9) */
#endif
};
#define	KNOWN_OPTIONS (sizeof(rfc1048_opts) / sizeof(rfc1048_opts[0]))

static void
rfc1048_print(bp, length)
	u_char *bp;
	int length;
{
	u_char tag;
	u_char *ep;
	int len;
	u_int32 ul;
	u_short us;
	struct in_addr ia;
	char *optstr;

	printf("-rfc1395");

	/* Step over magic cookie */
	bp += sizeof(int32);
	/* Setup end pointer */
	ep = bp + length;
	while (bp < ep) {
		tag = *bp++;
		/* Check for tags with no data first. */
		if (tag == TAG_PAD)
			continue;
		if (tag == TAG_END)
			return;
		if (tag < KNOWN_OPTIONS) {
			optstr = rfc1048_opts[tag];
			printf(" %s:", optstr + 1);
		} else {
			printf(" T%d:", tag);
			optstr = "?";
		}
		/* Now scan the length byte. */
		len = *bp++;
		if (bp + len > ep) {
			/* truncated option */
			printf(" |(%d>%td)", len, ep - bp);
			return;
		}
		/* Print the option value(s). */
		switch (optstr[0]) {

		case 'a':				/* ASCII string */
			printfn(bp, bp + len);
			bp += len;
			len = 0;
			break;

		case 's':				/* Word formats */
			while (len >= 2) {
				bcopy((char *) bp, (char *) &us, 2);
				printf("%d", ntohs(us));
				bp += 2;
				len -= 2;
				if (len) printf(",");
			}
			if (len) printf("(junk=%d)", len);
			break;

		case 'l':				/* Long words */
			while (len >= 4) {
				bcopy((char *) bp, (char *) &ul, 4);
				printf("%ld", (long)ntohl(ul));
				bp += 4;
				len -= 4;
				if (len) printf(",");
			}
			if (len) printf("(junk=%d)", len);
			break;

		case 'i':				/* INET addresses */
			while (len >= 4) {
				bcopy((char *) bp, (char *) &ia, 4);
				printf("%s", ipaddr_string(&ia));
				bp += 4;
				len -= 4;
				if (len) printf(",");
			}
			if (len) printf("(junk=%d)", len);
			break;

		case 'b':
		default:
			break;

		}						/* switch */

		/* Print as characters, if appropriate. */
		if (len) {
			dump_hex(bp, len);
			if (isascii(*bp) && isprint(*bp)) {
				printf("(");
				printfn(bp, bp + len);
				printf(")");
			}
			bp += len;
			len = 0;
		}
	} /* while bp < ep */
}

static void
cmu_print(bp, length)
	u_char *bp;
	int length;
{
	struct cmu_vend *v;

	printf("-cmu");

	v = (struct cmu_vend *) bp;
	if (length < sizeof(*v)) {
		printf(" |L=%d", length);
		return;
	}

	/* Subnet mask */
	if (v->v_flags & VF_SMASK) {
		printf(" SM:%s", ipaddr_string(&v->v_smask));
	}
	/* Default gateway */
	if (v->v_dgate.s_addr)
		printf(" GW:%s", ipaddr_string(&v->v_dgate));

	/* Domain name servers */
	if (v->v_dns1.s_addr)
		printf(" DNS1:%s", ipaddr_string(&v->v_dns1));
	if (v->v_dns2.s_addr)
		printf(" DNS2:%s", ipaddr_string(&v->v_dns2));

	/* IEN-116 name servers */
	if (v->v_ins1.s_addr)
		printf(" INS1:%s", ipaddr_string(&v->v_ins1));
	if (v->v_ins2.s_addr)
		printf(" INS2:%s", ipaddr_string(&v->v_ins2));

	/* Time servers */
	if (v->v_ts1.s_addr)
		printf(" TS1:%s", ipaddr_string(&v->v_ts1));
	if (v->v_ts2.s_addr)
		printf(" TS2:%s", ipaddr_string(&v->v_ts2));

}


/*
 * Print out arbitrary, unknown vendor data.
 */

static void
other_print(bp, length)
	u_char *bp;
	int length;
{
	u_char *ep;					/* end pointer */
	u_char *zp;					/* points one past last non-zero byte */

	/* Setup end pointer */
	ep = bp + length;

	/* Find the last non-zero byte. */
	for (zp = ep; zp > bp; zp--) {
		if (zp[-1] != 0)
			break;
	}

	/* Print the all-zero case in a compact representation. */
	if (zp == bp) {
		printf("-all-zero");
		return;
	}
	printf("-unknown");

	/* Are there enough trailing zeros to make "00..." worthwhile? */
	if (zp + 2 > ep)
		zp = ep;				/* print them all normally */

	/* Now just print all the non-zero data. */
	while (bp < zp) {
		printf(".%02X", *bp);
		bp++;
	}

	if (zp < ep)
		printf(".00...");

	return;
}

static void
dump_hex(bp, len)
	u_char *bp;
	int len;
{
	while (len > 0) {
		printf("%02X", *bp);
		bp++;
		len--;
		if (len) printf(".");
	}
}

/*
 * Local Variables:
 * tab-width: 4
 * c-indent-level: 4
 * c-argdecl-indent: 4
 * c-continued-statement-offset: 4
 * c-continued-brace-offset: -4
 * c-label-offset: -4
 * c-brace-offset: 0
 * End:
 */