summaryrefslogtreecommitdiff
path: root/net/bootp.c
blob: 4be0ad586a6b5f3e4de75c395cadab5de677be50 (plain)
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
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
/*
 *	Based on LiMon - BOOTP.
 *
 *	Copyright 1994, 1995, 2000 Neil Russell.
 *	(See License)
 *	Copyright 2000 Roland Borde
 *	Copyright 2000 Paolo Scaffardi
 *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
 */

#if 0
#define	DEBUG		1	/* general debug */
#define DEBUG_BOOTP_EXT	1	/* Debug received vendor fields	*/
#endif

#ifdef DEBUG_BOOTP_EXT
#define debug_ext(fmt,args...)	printf (fmt ,##args)
#else
#define debug_ext(fmt,args...)
#endif

#include <common.h>
#include <command.h>
#include <net.h>
#include "bootp.h"
#include "tftp.h"
#include "arp.h"
#ifdef CONFIG_STATUS_LED
#include <status_led.h>
#endif

#define	BOOTP_VENDOR_MAGIC	0x63825363 	/* RFC1048 Magic Cookie 	*/

#if (CONFIG_COMMANDS & CFG_CMD_NET)

#define TIMEOUT		5		/* Seconds before trying BOOTP again	*/
#ifndef	CONFIG_NET_RETRY_COUNT
# define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
#else
# define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
#endif

#define PORT_BOOTPS	67		/* BOOTP server UDP port		*/
#define PORT_BOOTPC	68		/* BOOTP client UDP port		*/

#ifndef CONFIG_DHCP_MIN_EXT_LEN		/* minimal length of extension list	*/
#define	CONFIG_DHCP_MIN_EXT_LEN	64
#endif

ulong		BootpID;
int		BootpTry;
#ifdef CONFIG_BOOTP_RANDOM_DELAY
ulong		seed1, seed2;
#endif

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
dhcp_state_t dhcp_state = INIT;
unsigned long dhcp_leasetime = 0;
IPaddr_t NetDHCPServerIP = 0;
static void DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len);

/* For Debug */
#if 0
static char *dhcpmsg2str(int type)
{
	switch (type) {
	case 1:  return "DHCPDISCOVER";	break;
	case 2:  return "DHCPOFFER";	break;
	case 3:  return "DHCPREQUEST";	break;
	case 4:  return "DHCPDECLINE";	break;
	case 5:  return "DHCPACK";	break;
	case 6:  return "DHCPNACK";	break;
	case 7:  return "DHCPRELEASE";	break;
	default: return "UNKNOWN/INVALID MSG TYPE"; break;
	}
}
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
extern u8 *dhcp_vendorex_prep (u8 *e); /*rtn new e after add own opts. */
extern u8 *dhcp_vendorex_proc (u8 *e); /*rtn next e if mine,else NULL  */
#endif

#endif	/* CFG_CMD_DHCP */

static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp = (Bootp_t *) pkt;
	int retval = 0;

	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
		retval = -1;
	else if (len < sizeof (Bootp_t) - OPT_SIZE)
		retval = -2;
	else if (bp->bp_op != OP_BOOTREQUEST &&
	    bp->bp_op != OP_BOOTREPLY &&
	    bp->bp_op != DHCP_OFFER &&
	    bp->bp_op != DHCP_ACK &&
	    bp->bp_op != DHCP_NAK ) {
		retval = -3;
	}
	else if (bp->bp_htype != HWT_ETHER)
		retval = -4;
	else if (bp->bp_hlen != HWL_ETHER)
		retval = -5;
	else if (NetReadLong((ulong*)&bp->bp_id) != BootpID) {
		retval = -6;
	}

	debug ("Filtering pkt = %d\n", retval);

	return retval;
}

/*
 * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
 */
static void BootpCopyNetParams(Bootp_t *bp)
{
	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);
	NetCopyIP(&NetServerIP, &bp->bp_siaddr);
	memcpy (NetServerEther, ((Ethernet_t *)NetRxPkt)->et_src, 6);
	copy_filename (BootFile, bp->bp_file, sizeof(BootFile));

	debug ("Bootfile: %s\n", BootFile);

	/* Propagate to environment:
         * don't delete exising entry when BOOTP / DHCP reply does
	 * not contain a new value
	 */
	if (*BootFile) {
		setenv ("bootfile", BootFile);
	}
}

static int truncate_sz (const char *name, int maxlen, int curlen)
{
	if (curlen >= maxlen) {
		printf("*** WARNING: %s is too long (%d - max: %d) - truncated\n",
			name, curlen, maxlen);
		curlen = maxlen - 1;
	}
	return (curlen);
}

#if !(CONFIG_COMMANDS & CFG_CMD_DHCP)

static void BootpVendorFieldProcess(u8 *ext)
{
    int size = *(ext+1) ;

    debug_ext ("[BOOTP] Processing extension %d... (%d bytes)\n", *ext, *(ext+1));

    NetBootFileSize = 0;

    switch (*ext) {
    /* Fixed length fields */
	case 1:		/* Subnet mask					*/
		if (NetOurSubnetMask == 0)
			NetCopyIP(&NetOurSubnetMask, (IPaddr_t*)(ext+2));
		break;
	case 2:		/* Time offset - Not yet supported		*/
		break;
    /* Variable length fields */
	case 3:		/* Gateways list				*/
		if (NetOurGatewayIP == 0) {
			NetCopyIP(&NetOurGatewayIP, (IPaddr_t*)(ext+2));
		}
		break;
	case 4:		/* Time server - Not yet supported		*/
		break;
	case 5:		/* IEN-116 name server - Not yet supported	*/
		break;
	case 6:
		if (NetOurDNSIP == 0) {
			NetCopyIP(&NetOurDNSIP, (IPaddr_t*)(ext+2));
		}
		break;
	case 7:		/* Log server - Not yet supported		*/
		break;
	case 8:		/* Cookie/Quote server - Not yet supported	*/
		break;
	case 9:		/* LPR server - Not yet supported		*/
		break;
	case 10:	/* Impress server - Not yet supported		*/
		break;
	case 11:	/* RPL server - Not yet supported		*/
		break;
	case 12:	/* Host name					*/
		if (NetOurHostName[0] == 0) {
		    size = truncate_sz("Host Name", sizeof(NetOurHostName), size);
		    memcpy(&NetOurHostName, ext+2, size);
		    NetOurHostName[size] = 0 ;
		}
		break;
	case 13:	/* Boot file size				*/
		if (size == 2)
			NetBootFileSize = ntohs(*(ushort*)(ext+2));
		else if (size == 4)
			NetBootFileSize = ntohl(*(ulong*)(ext+2));
		break;
	case 14:	/* Merit dump file - Not yet supported		*/
		break;
	case 15:	/* Domain name - Not yet supported		*/
		break;
	case 16:	/* Swap server - Not yet supported		*/
		break;
	case 17:	/* Root path					*/
		if (NetOurRootPath[0] == 0) {
		    size = truncate_sz("Root Path", sizeof(NetOurRootPath), size);
		    memcpy(&NetOurRootPath, ext+2, size);
		    NetOurRootPath[size] = 0 ;
		}
		break;
	case 18:	/* Extension path - Not yet supported		*/
		/*
                 * This can be used to send the information of the
                 * vendor area in another file that the client can
                 * access via TFTP.
		 */
		break;
    /* IP host layer fields */
	case 40:	/* NIS Domain name				*/
		if (NetOurNISDomain[0] == 0) {
		    size = truncate_sz ("NIS Domain Name",
		    			sizeof(NetOurNISDomain),
					size);
		    memcpy(&NetOurNISDomain, ext+2, size);
		    NetOurNISDomain[size] = 0 ;
		}
		break;
    /* Application layer fields */
	case 43:	/* Vendor specific info - Not yet supported	*/
		/*
                 * Binary information to exchange specific
                 * product information.
		 */
		break;
    /* Reserved (custom) fields (128..254) */
    }
}

static void BootpVendorProcess(u8 *ext, int size)
{
    u8 *end = ext + size ;

    debug_ext ("[BOOTP] Checking extension (%d bytes)...\n", size);

    while ((ext < end) && (*ext != 0xff)) {
	if (*ext == 0) {
	    ext ++ ;
	} else {
		u8 *opt = ext ;
		ext += ext[1] + 2 ;
		if (ext <= end)
		    BootpVendorFieldProcess (opt) ;
	}
    }

#ifdef DEBUG_BOOTP_EXT
    printf("[BOOTP] Received fields: \n");
    if (NetOurSubnetMask) {
	puts ("NetOurSubnetMask	: ");
	print_IPaddr (NetOurSubnetMask);
	putc('\n');
    }

    if (NetOurGatewayIP) {
	puts ("NetOurGatewayIP	: ");
	print_IPaddr (NetOurGatewayIP);
	putc('\n');
    }

    if (NetBootFileSize) {
	printf("NetBootFileSize : %d\n", NetBootFileSize);
    }

    if (NetOurHostName[0]) {
	printf("NetOurHostName  : %s\n", NetOurHostName);
    }

    if (NetOurRootPath[0]) {
	printf("NetOurRootPath  : %s\n", NetOurRootPath);
    }

    if (NetOurNISDomain[0]) {
        printf("NetOurNISDomain : %s\n", NetOurNISDomain);
    }

    if (NetBootFileSize) {
	printf("NetBootFileSize: %d\n", NetBootFileSize);
    }
#endif	/* DEBUG_BOOTP_EXT */
}

/*
 *	Handle a BOOTP received packet.
 */
static void
BootpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp;
	char	*s;

	debug ("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%d)\n",
		src, dest, len, sizeof (Bootp_t));

	bp = (Bootp_t *)pkt;

	if (BootpCheckPkt(pkt, dest, src, len))	/* Filter out pkts we don't want */
		return;

	/*
	 *	Got a good BOOTP reply.  Copy the data into our variables.
	 */
#ifdef CONFIG_STATUS_LED
	status_led_set (STATUS_LED_BOOT, STATUS_LED_OFF);
#endif

	BootpCopyNetParams(bp);		/* Store net parameters from reply */

	/* Retrieve extended information (we must parse the vendor area) */
	if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
		BootpVendorProcess(&bp->bp_vend[4], len);

	NetSetTimeout(0, (thand_f *)0);

	debug ("Got good BOOTP\n");

	if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
		/*
		 * Just use BOOTP to configure system;
		 * Do not use TFTP to load the bootfile.
		 */
		NetState = NETLOOP_SUCCESS;
		return;
	}

	/* Send ARP request to get TFTP server ethernet address.
	 * This automagically starts TFTP, too.
	 */
	ArpRequest();
}
#endif	/* !CFG_CMD_DHCP */

/*
 *	Timeout on BOOTP/DHCP request.
 */
static void
BootpTimeout(void)
{
	if (BootpTry >= TIMEOUT_COUNT) {
		puts ("\nRetry count exceeded; starting again\n");
		NetStartAgain ();
	} else {
		NetSetTimeout (TIMEOUT * CFG_HZ, BootpTimeout);
		BootpRequest ();
	}
}

/*
 *	Initialize BOOTP extension fields in the request.
 */
#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
static int DhcpExtended(u8 *e, int message_type, IPaddr_t ServerID, IPaddr_t RequestedIP)
{
    u8 *start = e ;
    u8 *cnt;
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
    u8 *x;
#endif

    *e++ =  99;		/* RFC1048 Magic Cookie */
    *e++ = 130;
    *e++ =  83;
    *e++ =  99;

    *e++ = 53;		/* DHCP Message Type */
    *e++ = 1;
    *e++ = message_type;

    *e++ = 57;		/* Maximum DHCP Message Size */
    *e++ = 2;
    *e++ = (576-312+OPT_SIZE) >> 8;
    *e++ = (576-312+OPT_SIZE) & 0xff;

    if ( ServerID ) {
    	    int tmp = ntohl(ServerID);

	    *e++ = 54;	/* ServerID */
	    *e++ = 4;
	    *e++ = tmp >> 24;
	    *e++ = tmp >> 16;
	    *e++ = tmp >> 8;
	    *e++ = tmp & 0xff;
    }

    if ( RequestedIP ) {
    	    int tmp = ntohl(RequestedIP);

	    *e++ = 50;	/* Requested IP */
	    *e++ = 4;
	    *e++ = tmp >> 24;
	    *e++ = tmp >> 16;
	    *e++ = tmp >> 8;
	    *e++ = tmp & 0xff;
    }

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
    if ((x = dhcp_vendorex_prep (e)))
    	return x - start ;
#endif

    *e++ = 55;		/* Parameter Request List */
    cnt  = e++;		/* Pointer to count of requested items */
    *cnt = 0;
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
    *e++ = 1;		/* Subnet Mask */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
    *e++ = 3;		/* Router Option */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
    *e++ = 6;		/* DNS Server(s) */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
    *e++ = 12;		/* Hostname */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
    *e++ = 13;		/* Boot File Size */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
    *e++ = 17;		/* Boot path */
    *cnt += 1;
#endif
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
    *e++ = 40;		/* NIS Domain name request */
    *cnt += 1;
#endif
    *e++ = 255;		/* End of the list */

    /* Pad to minimal length */
#ifdef	CONFIG_DHCP_MIN_EXT_LEN
    while ((e - start) <= CONFIG_DHCP_MIN_EXT_LEN)
	*e++ = 0;
#endif

    return e - start ;
}

#else	/* CFG_CMD_DHCP */
/*
 *	Warning: no field size check - change CONFIG_BOOTP_MASK at your own risk!
 */
static int BootpExtended (u8 *e)
{
    u8 *start = e ;

    *e++ =  99;		/* RFC1048 Magic Cookie */
    *e++ = 130;
    *e++ =  83;
    *e++ =  99;

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
    *e++ = 53;		/* DHCP Message Type */
    *e++ = 1;
    *e++ = DHCP_DISCOVER;

    *e++ = 57;		/* Maximum DHCP Message Size */
    *e++ = 2;
    *e++ = (576-312+OPT_SIZE) >> 16;
    *e++ = (576-312+OPT_SIZE) & 0xff;
#endif	/* CFG_CMD_DHCP */

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
    *e++ =  1;		/* Subnet mask request */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
    *e++ =  3;		/* Default gateway request */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
    *e++ =  6;		/* Domain Name Server */
    *e++ =  4;
     e  +=  4;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
    *e++ = 12;		/* Host name request */
    *e++ = 32;
     e  += 32;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
    *e++ = 13;		/* Boot file size */
    *e++ =  2;
     e  +=  2;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
    *e++ = 17;		/* Boot path */
    *e++ = 32;
     e  += 32;
#endif

#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
    *e++ = 40;		/* NIS Domain name request */
    *e++ = 32;
     e  += 32;
#endif

    *e++ = 255;		/* End of the list */

    return e - start ;
}
#endif	/* CFG_CMD_DHCP */

void
BootpRequest (void)
{
	volatile uchar *pkt, *iphdr;
	Bootp_t *bp;
	int ext_len, pktlen, iplen;

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
	dhcp_state = INIT;
#endif

#ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */
	unsigned char bi_enetaddr[6];
	int   reg;
	char  *e,*s;
	uchar tmp[64];
	ulong tst1, tst2, sum, m_mask, m_value = 0;

	if (BootpTry ==0) {
		/* get our mac */
		reg = getenv_r ("ethaddr", tmp, sizeof(tmp));
		s = (reg > 0) ? tmp : NULL;

		for (reg=0; reg<6; ++reg) {
			bi_enetaddr[reg] = s ? simple_strtoul(s, &e, 16) : 0;
			if (s) {
				s = (*e) ? e+1 : e;
			}
		}
#ifdef DEBUG
		printf("BootpRequest => Our Mac: ");
		for (reg=0; reg<6; reg++) {
			printf ("%x%c",
				bi_enetaddr[reg],
				reg==5 ? '\n' : ':');
		}
#endif /* DEBUG */

		/* Mac-Manipulation 2 get seed1 */
		tst1=0;
		tst2=0;
		for (reg=2; reg<6; reg++) {
			tst1 = tst1 << 8;
			tst1 = tst1 | bi_enetaddr[reg];
		}
		for (reg=0; reg<2; reg++) {
			tst2 = tst2 | bi_enetaddr[reg];
			tst2 = tst2 << 8;
		}

		seed1 = tst1^tst2;

		/* Mirror seed1*/
		m_mask=0x1;
		for (reg=1;reg<=32;reg++) {
			m_value |= (m_mask & seed1);
			seed1 = seed1 >> 1;
			m_value = m_value << 1;
		}
		seed1 = m_value;
		seed2 = 0xB78D0945;
	}

	/* Random Number Generator */

	for (reg=0;reg<=0;reg++) {
		sum = seed1 + seed2;
		if (sum < seed1 || sum < seed2)
			sum++;
	        seed2 = seed1;
		seed1 = sum;

		if (BootpTry<=2) {	/* Start with max 1024 * 1ms */
			sum = sum >> (22-BootpTry);
		} else {		/*After 3rd BOOTP request max 8192 * 1ms */
			sum = sum >> 19;
		}
	}

	printf ("Random delay: %ld ms...\n", sum);
	for (reg=0; reg <sum; reg++) {
		udelay(1000); /*Wait 1ms*/
	}
#endif	/* CONFIG_BOOTP_RANDOM_DELAY */

	printf("BOOTP broadcast %d\n", ++BootpTry);
	pkt = NetTxPacket;
	memset ((void*)pkt, 0, PKTSIZE);

	NetSetEther(pkt, NetBcastAddr, PROT_IP);
	pkt += ETHER_HDR_SIZE;

	/*
	 * Next line results in incorrect packet size being transmitted, resulting
	 * in errors in some DHCP servers, reporting missing bytes.  Size must be
	 * set in packet header after extension length has been determined.
	 * C. Hallinan, DS4.COM, Inc.
	 */
	/* NetSetIP(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, sizeof (Bootp_t)); */
	iphdr = pkt;	/* We need this later for NetSetIP() */
	pkt += IP_HDR_SIZE;

	bp = (Bootp_t *)pkt;
	bp->bp_op = OP_BOOTREQUEST;
	bp->bp_htype = HWT_ETHER;
	bp->bp_hlen = HWL_ETHER;
	bp->bp_hops = 0;
	bp->bp_secs = htons(get_timer(0) / CFG_HZ);
	NetWriteIP(&bp->bp_ciaddr, 0);
	NetWriteIP(&bp->bp_yiaddr, 0);
	NetWriteIP(&bp->bp_siaddr, 0);
	NetWriteIP(&bp->bp_giaddr, 0);
	memcpy (bp->bp_chaddr, NetOurEther, 6);
	copy_filename (bp->bp_file, BootFile, sizeof(bp->bp_file));

	/* Request additional information from the BOOTP/DHCP server */
#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
	ext_len = DhcpExtended(bp->bp_vend, DHCP_DISCOVER, 0, 0);
#else
	ext_len = BootpExtended(bp->bp_vend);
#endif	/* CFG_CMD_DHCP */

	/*
	 *	Bootp ID is the lower 4 bytes of our ethernet address
	 *	plus the current time in HZ.
	 */
	BootpID = ((ulong)NetOurEther[2] << 24)
		| ((ulong)NetOurEther[3] << 16)
		| ((ulong)NetOurEther[4] << 8)
		| (ulong)NetOurEther[5];
	BootpID += get_timer(0);
	BootpID  = htonl(BootpID);
	NetCopyLong(&bp->bp_id, &BootpID);

	/*
	 * Calculate proper packet lengths taking into account the
	 * variable size of the options field
	 */
	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + ext_len;
	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
	NetSetTimeout(SELECT_TIMEOUT * CFG_HZ, BootpTimeout);

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
	dhcp_state = SELECTING;
	NetSetHandler(DhcpHandler);
#else
	NetSetHandler(BootpHandler);
#endif	/* CFG_CMD_DHCP */
	NetSendPacket(NetTxPacket, pktlen);
}

#if (CONFIG_COMMANDS & CFG_CMD_DHCP)
static void DhcpOptionsProcess(uchar *popt)
{
	uchar *end = popt + BOOTP_HDR_SIZE;
	int oplen, size;

	while ( popt < end && *popt != 0xff ) {
		oplen = *(popt + 1);
		switch(*popt) {
			case  1:
				NetCopyIP(&NetOurSubnetMask, (popt+2));
				break;
			case  3:
				NetCopyIP(&NetOurGatewayIP, (popt+2));
				break;
			case  6:
				NetCopyIP(&NetOurDNSIP, (popt+2));
				break;
			case 12:
				size = truncate_sz ("Host Name",
						    sizeof(NetOurHostName),
						    oplen);
				memcpy(&NetOurHostName, popt+2, size);
				NetOurHostName[size] = 0 ;
				break;
			case 15:		/* Ignore Domain Name Option */
				break;
			case 17:
				size = truncate_sz ("Root Path",
						    sizeof(NetOurRootPath),
						    oplen);
				memcpy(&NetOurRootPath, popt+2, size);
				NetOurRootPath[size] = 0 ;
				break;
			case 51:
				NetCopyLong (&dhcp_leasetime, (ulong *)(popt + 2));
				break;
			case 53:		/* Ignore Message Type Option */
				break;
			case 54:
				NetCopyIP(&NetDHCPServerIP, (popt+2));
				break;
			case 58:		/* Ignore Renewal Time Option */
				break;
			case 59:		/* Ignore Rebinding Time Option */
				break;
			default:
#if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
			    if (dhcp_vendorex_proc(popt))
        			break;
#endif
				printf("*** Unhandled DHCP Option in OFFER/ACK: %d\n",
					*popt);
				break;
		}
		popt += oplen + 2;	/* Process next option */
	}
}

static int DhcpMessageType(unsigned char *popt)
{
	if (NetReadLong((ulong*)popt) != htonl(BOOTP_VENDOR_MAGIC))
		return -1;

	popt += 4;
	while ( *popt != 0xff ) {
		if ( *popt == 53 )	/* DHCP Message Type */
			return *(popt + 2);
		popt += *(popt + 1) + 2;	/* Scan through all options */
	}
	return -1;
}

static void DhcpSendRequestPkt(Bootp_t *bp_offer)
{
	volatile uchar *pkt, *iphdr;
	Bootp_t *bp;
	int pktlen, iplen, extlen;
	IPaddr_t OfferedIP;

	debug ("DhcpSendRequestPkt: Sending DHCPREQUEST\n");
	pkt = NetTxPacket;
	memset ((void*)pkt, 0, PKTSIZE);

	NetSetEther(pkt, NetBcastAddr, PROT_IP);
	pkt += ETHER_HDR_SIZE;

	iphdr = pkt;		/* We'll need this later to set proper pkt size */
	pkt += IP_HDR_SIZE;

	bp = (Bootp_t *)pkt;
	bp->bp_op = OP_BOOTREQUEST;
	bp->bp_htype = HWT_ETHER;
	bp->bp_hlen = HWL_ETHER;
	bp->bp_hops = 0;
	bp->bp_secs = htons(get_timer(0) / CFG_HZ);
	NetCopyIP(&bp->bp_ciaddr, &bp_offer->bp_ciaddr); /* both in network byte order */
	NetCopyIP(&bp->bp_yiaddr, &bp_offer->bp_yiaddr);
	NetCopyIP(&bp->bp_siaddr, &bp_offer->bp_siaddr);
	NetCopyIP(&bp->bp_giaddr, &bp_offer->bp_giaddr);
	memcpy (bp->bp_chaddr, NetOurEther, 6);

	/*
	 * ID is the id of the OFFER packet
	 */

	NetCopyLong(&bp->bp_id, &bp_offer->bp_id);

	/*
	 * Copy options from OFFER packet if present
	 */
	NetCopyIP(&OfferedIP, &bp->bp_yiaddr);
	extlen = DhcpExtended(bp->bp_vend, DHCP_REQUEST, NetDHCPServerIP, OfferedIP);

	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + extlen;
	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);

	debug ("Transmitting DHCPREQUEST packet: len = %d\n", pktlen);
	NetSendPacket(NetTxPacket, pktlen);
}

/*
 *	Handle DHCP received packets.
 */
static void
DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
{
	Bootp_t *bp = (Bootp_t *)pkt;

	debug ("DHCPHandler: got packet: (src=%d, dst=%d, len=%d) state: %d\n",
		src, dest, len, dhcp_state);

	if (BootpCheckPkt(pkt, dest, src, len))	/* Filter out pkts we don't want */
		return;

	debug ("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: %d\n",
		src, dest, len, dhcp_state);

	switch (dhcp_state) {
	case SELECTING:
		/*
		 * Wait an appropriate time for any potential DHCPOFFER packets
		 * to arrive.  Then select one, and generate DHCPREQUEST response.
		 * If filename is in format we recognize, assume it is a valid
		 * OFFER from a server we want.
		 */
		debug ("DHCP: state=SELECTING bp_file: \"%s\"\n", bp->bp_file);
#ifdef CFG_BOOTFILE_PREFIX
		if (strncmp(bp->bp_file,
			    CFG_BOOTFILE_PREFIX,
			    strlen(CFG_BOOTFILE_PREFIX)) == 0 ) {
#endif	/* CFG_BOOTFILE_PREFIX */

			debug ("TRANSITIONING TO REQUESTING STATE\n");
			dhcp_state = REQUESTING;

			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
				DhcpOptionsProcess(&bp->bp_vend[4]);

			BootpCopyNetParams(bp);	/* Store net params from reply */

			NetSetTimeout(TIMEOUT * CFG_HZ, BootpTimeout);
			DhcpSendRequestPkt(bp);
#ifdef CFG_BOOTFILE_PREFIX
		}
#endif	/* CFG_BOOTFILE_PREFIX */

		return;
		break;
	case REQUESTING:
		debug ("DHCP State: REQUESTING\n");

		if ( DhcpMessageType(bp->bp_vend) == DHCP_ACK ) {
			char *s;

			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
				DhcpOptionsProcess(&bp->bp_vend[4]);
			BootpCopyNetParams(bp);	/* Store net params from reply */
			dhcp_state = BOUND;
			printf("DHCP client bound to address ");
			print_IPaddr(NetOurIP);
			printf("\n");

			/* Obey the 'autoload' setting */
			if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
				NetState = NETLOOP_SUCCESS;
				return;
			}
			/* Send ARP request to get TFTP server ethernet address.
			 * This automagically starts TFTP, too.
			 */
			ArpRequest();
			return;
		}
		break;
	default:
		printf("DHCP: INVALID STATE\n");
		break;
	}

}

void DhcpRequest(void)
{
	BootpRequest();
}
#endif	/* CFG_CMD_DHCP */

#endif /* CFG_CMD_NET */