xref: /openbmc/u-boot/net/bootp.c (revision ed56fb1d)
1 /*
2  *	Based on LiMon - BOOTP.
3  *
4  *	Copyright 1994, 1995, 2000 Neil Russell.
5  *	(See License)
6  *	Copyright 2000 Roland Borde
7  *	Copyright 2000 Paolo Scaffardi
8  *	Copyright 2000-2004 Wolfgang Denk, wd@denx.de
9  */
10 
11 #include <common.h>
12 #include <command.h>
13 #include <net.h>
14 #include "bootp.h"
15 #include "tftp.h"
16 #include "nfs.h"
17 #ifdef CONFIG_STATUS_LED
18 #include <status_led.h>
19 #endif
20 
21 #define BOOTP_VENDOR_MAGIC	0x63825363	/* RFC1048 Magic Cookie		*/
22 
23 #define TIMEOUT		5000UL	/* Milliseconds before trying BOOTP again */
24 #ifndef CONFIG_NET_RETRY_COUNT
25 # define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
26 #else
27 # define TIMEOUT_COUNT	(CONFIG_NET_RETRY_COUNT)
28 #endif
29 
30 #define PORT_BOOTPS	67		/* BOOTP server UDP port		*/
31 #define PORT_BOOTPC	68		/* BOOTP client UDP port		*/
32 
33 #ifndef CONFIG_DHCP_MIN_EXT_LEN		/* minimal length of extension list	*/
34 #define CONFIG_DHCP_MIN_EXT_LEN 64
35 #endif
36 
37 ulong		BootpID;
38 int		BootpTry;
39 #ifdef CONFIG_BOOTP_RANDOM_DELAY
40 ulong		seed1, seed2;
41 #endif
42 
43 #if defined(CONFIG_CMD_DHCP)
44 dhcp_state_t dhcp_state = INIT;
45 unsigned long dhcp_leasetime = 0;
46 IPaddr_t NetDHCPServerIP = 0;
47 static void DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len);
48 
49 /* For Debug */
50 #if 0
51 static char *dhcpmsg2str(int type)
52 {
53 	switch (type) {
54 	case 1:	 return "DHCPDISCOVER"; break;
55 	case 2:	 return "DHCPOFFER";	break;
56 	case 3:	 return "DHCPREQUEST";	break;
57 	case 4:	 return "DHCPDECLINE";	break;
58 	case 5:	 return "DHCPACK";	break;
59 	case 6:	 return "DHCPNACK";	break;
60 	case 7:	 return "DHCPRELEASE";	break;
61 	default: return "UNKNOWN/INVALID MSG TYPE"; break;
62 	}
63 }
64 #endif
65 
66 #if defined(CONFIG_BOOTP_VENDOREX)
67 extern u8 *dhcp_vendorex_prep (u8 *e); /*rtn new e after add own opts. */
68 extern u8 *dhcp_vendorex_proc (u8 *e); /*rtn next e if mine,else NULL  */
69 #endif
70 
71 #endif
72 
73 static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
74 {
75 	Bootp_t *bp = (Bootp_t *) pkt;
76 	int retval = 0;
77 
78 	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
79 		retval = -1;
80 	else if (len < sizeof (Bootp_t) - OPT_SIZE)
81 		retval = -2;
82 	else if (bp->bp_op != OP_BOOTREQUEST &&
83 	    bp->bp_op != OP_BOOTREPLY &&
84 	    bp->bp_op != DHCP_OFFER &&
85 	    bp->bp_op != DHCP_ACK &&
86 	    bp->bp_op != DHCP_NAK ) {
87 		retval = -3;
88 	}
89 	else if (bp->bp_htype != HWT_ETHER)
90 		retval = -4;
91 	else if (bp->bp_hlen != HWL_ETHER)
92 		retval = -5;
93 	else if (NetReadLong((ulong*)&bp->bp_id) != BootpID) {
94 		retval = -6;
95 	}
96 
97 	debug("Filtering pkt = %d\n", retval);
98 
99 	return retval;
100 }
101 
102 /*
103  * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
104  */
105 static void BootpCopyNetParams(Bootp_t *bp)
106 {
107 	IPaddr_t tmp_ip;
108 
109 	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);
110 #if !defined(CONFIG_BOOTP_SERVERIP)
111 	NetCopyIP(&tmp_ip, &bp->bp_siaddr);
112 	if (tmp_ip != 0)
113 		NetCopyIP(&NetServerIP, &bp->bp_siaddr);
114 	memcpy (NetServerEther, ((Ethernet_t *)NetRxPacket)->et_src, 6);
115 #endif
116 	if (strlen(bp->bp_file) > 0)
117 		copy_filename (BootFile, bp->bp_file, sizeof(BootFile));
118 
119 	debug("Bootfile: %s\n", BootFile);
120 
121 	/* Propagate to environment:
122 	 * don't delete exising entry when BOOTP / DHCP reply does
123 	 * not contain a new value
124 	 */
125 	if (*BootFile) {
126 		setenv ("bootfile", BootFile);
127 	}
128 }
129 
130 static int truncate_sz (const char *name, int maxlen, int curlen)
131 {
132 	if (curlen >= maxlen) {
133 		printf("*** WARNING: %s is too long (%d - max: %d) - truncated\n",
134 			name, curlen, maxlen);
135 		curlen = maxlen - 1;
136 	}
137 	return (curlen);
138 }
139 
140 #if !defined(CONFIG_CMD_DHCP)
141 
142 static void BootpVendorFieldProcess (u8 * ext)
143 {
144 	int size = *(ext + 1);
145 
146 	debug("[BOOTP] Processing extension %d... (%d bytes)\n", *ext,
147 		   *(ext + 1));
148 
149 	NetBootFileSize = 0;
150 
151 	switch (*ext) {
152 		/* Fixed length fields */
153 	case 1:			/* Subnet mask					*/
154 		if (NetOurSubnetMask == 0)
155 			NetCopyIP (&NetOurSubnetMask, (IPaddr_t *) (ext + 2));
156 		break;
157 	case 2:			/* Time offset - Not yet supported		*/
158 		break;
159 		/* Variable length fields */
160 	case 3:			/* Gateways list				*/
161 		if (NetOurGatewayIP == 0) {
162 			NetCopyIP (&NetOurGatewayIP, (IPaddr_t *) (ext + 2));
163 		}
164 		break;
165 	case 4:			/* Time server - Not yet supported		*/
166 		break;
167 	case 5:			/* IEN-116 name server - Not yet supported	*/
168 		break;
169 	case 6:
170 		if (NetOurDNSIP == 0) {
171 			NetCopyIP (&NetOurDNSIP, (IPaddr_t *) (ext + 2));
172 		}
173 #if defined(CONFIG_BOOTP_DNS2)
174 		if ((NetOurDNS2IP == 0) && (size > 4)) {
175 			NetCopyIP (&NetOurDNS2IP, (IPaddr_t *) (ext + 2 + 4));
176 		}
177 #endif
178 		break;
179 	case 7:			/* Log server - Not yet supported		*/
180 		break;
181 	case 8:			/* Cookie/Quote server - Not yet supported	*/
182 		break;
183 	case 9:			/* LPR server - Not yet supported		*/
184 		break;
185 	case 10:		/* Impress server - Not yet supported		*/
186 		break;
187 	case 11:		/* RPL server - Not yet supported		*/
188 		break;
189 	case 12:		/* Host name					*/
190 		if (NetOurHostName[0] == 0) {
191 			size = truncate_sz ("Host Name", sizeof (NetOurHostName), size);
192 			memcpy (&NetOurHostName, ext + 2, size);
193 			NetOurHostName[size] = 0;
194 		}
195 		break;
196 	case 13:		/* Boot file size				*/
197 		if (size == 2)
198 			NetBootFileSize = ntohs (*(ushort *) (ext + 2));
199 		else if (size == 4)
200 			NetBootFileSize = ntohl (*(ulong *) (ext + 2));
201 		break;
202 	case 14:		/* Merit dump file - Not yet supported		*/
203 		break;
204 	case 15:		/* Domain name - Not yet supported		*/
205 		break;
206 	case 16:		/* Swap server - Not yet supported		*/
207 		break;
208 	case 17:		/* Root path					*/
209 		if (NetOurRootPath[0] == 0) {
210 			size = truncate_sz ("Root Path", sizeof (NetOurRootPath), size);
211 			memcpy (&NetOurRootPath, ext + 2, size);
212 			NetOurRootPath[size] = 0;
213 		}
214 		break;
215 	case 18:		/* Extension path - Not yet supported		*/
216 		/*
217 		 * This can be used to send the information of the
218 		 * vendor area in another file that the client can
219 		 * access via TFTP.
220 		 */
221 		break;
222 		/* IP host layer fields */
223 	case 40:		/* NIS Domain name				*/
224 		if (NetOurNISDomain[0] == 0) {
225 			size = truncate_sz ("NIS Domain Name", sizeof (NetOurNISDomain), size);
226 			memcpy (&NetOurNISDomain, ext + 2, size);
227 			NetOurNISDomain[size] = 0;
228 		}
229 		break;
230 		/* Application layer fields */
231 	case 43:		/* Vendor specific info - Not yet supported	*/
232 		/*
233 		 * Binary information to exchange specific
234 		 * product information.
235 		 */
236 		break;
237 		/* Reserved (custom) fields (128..254) */
238 	}
239 }
240 
241 static void BootpVendorProcess (u8 * ext, int size)
242 {
243 	u8 *end = ext + size;
244 
245 	debug("[BOOTP] Checking extension (%d bytes)...\n", size);
246 
247 	while ((ext < end) && (*ext != 0xff)) {
248 		if (*ext == 0) {
249 			ext++;
250 		} else {
251 			u8 *opt = ext;
252 
253 			ext += ext[1] + 2;
254 			if (ext <= end)
255 				BootpVendorFieldProcess (opt);
256 		}
257 	}
258 
259 	debug("[BOOTP] Received fields: \n");
260 	if (NetOurSubnetMask)
261 		debug("NetOurSubnetMask : %pI4\n", &NetOurSubnetMask);
262 
263 	if (NetOurGatewayIP)
264 		debug("NetOurGatewayIP	: %pI4", &NetOurGatewayIP);
265 
266 	if (NetBootFileSize)
267 		debug("NetBootFileSize : %d\n", NetBootFileSize);
268 
269 	if (NetOurHostName[0])
270 		debug("NetOurHostName  : %s\n", NetOurHostName);
271 
272 	if (NetOurRootPath[0])
273 		debug("NetOurRootPath  : %s\n", NetOurRootPath);
274 
275 	if (NetOurNISDomain[0])
276 		debug("NetOurNISDomain : %s\n", NetOurNISDomain);
277 
278 	if (NetBootFileSize)
279 		debug("NetBootFileSize: %d\n", NetBootFileSize);
280 }
281 /*
282  *	Handle a BOOTP received packet.
283  */
284 static void
285 BootpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
286 {
287 	Bootp_t *bp;
288 	char	*s;
289 
290 	debug("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%zu)\n",
291 		src, dest, len, sizeof (Bootp_t));
292 
293 	bp = (Bootp_t *)pkt;
294 
295 	if (BootpCheckPkt(pkt, dest, src, len)) /* Filter out pkts we don't want */
296 		return;
297 
298 	/*
299 	 *	Got a good BOOTP reply.	 Copy the data into our variables.
300 	 */
301 #ifdef CONFIG_STATUS_LED
302 	status_led_set (STATUS_LED_BOOT, STATUS_LED_OFF);
303 #endif
304 
305 	BootpCopyNetParams(bp);		/* Store net parameters from reply */
306 
307 	/* Retrieve extended information (we must parse the vendor area) */
308 	if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
309 		BootpVendorProcess((uchar *)&bp->bp_vend[4], len);
310 
311 	NetSetTimeout(0, (thand_f *)0);
312 
313 	debug("Got good BOOTP\n");
314 
315 	if ((s = getenv("autoload")) != NULL) {
316 		if (*s == 'n') {
317 			/*
318 			 * Just use BOOTP to configure system;
319 			 * Do not use TFTP to load the bootfile.
320 			 */
321 			NetState = NETLOOP_SUCCESS;
322 			return;
323 #if defined(CONFIG_CMD_NFS)
324 		} else if (strcmp(s, "NFS") == 0) {
325 			/*
326 			 * Use NFS to load the bootfile.
327 			 */
328 			NfsStart();
329 			return;
330 #endif
331 		}
332 	}
333 
334 	TftpStart();
335 }
336 #endif
337 
338 /*
339  *	Timeout on BOOTP/DHCP request.
340  */
341 static void
342 BootpTimeout(void)
343 {
344 	if (BootpTry >= TIMEOUT_COUNT) {
345 		puts ("\nRetry count exceeded; starting again\n");
346 		NetStartAgain ();
347 	} else {
348 		NetSetTimeout (TIMEOUT, BootpTimeout);
349 		BootpRequest ();
350 	}
351 }
352 
353 /*
354  *	Initialize BOOTP extension fields in the request.
355  */
356 #if defined(CONFIG_CMD_DHCP)
357 static int DhcpExtended (u8 * e, int message_type, IPaddr_t ServerID, IPaddr_t RequestedIP)
358 {
359 	u8 *start = e;
360 	u8 *cnt;
361 
362 #if defined(CONFIG_BOOTP_VENDOREX)
363 	u8 *x;
364 #endif
365 #if defined(CONFIG_BOOTP_SEND_HOSTNAME)
366 	char *hostname;
367 #endif
368 
369 	*e++ = 99;		/* RFC1048 Magic Cookie */
370 	*e++ = 130;
371 	*e++ = 83;
372 	*e++ = 99;
373 
374 	*e++ = 53;		/* DHCP Message Type */
375 	*e++ = 1;
376 	*e++ = message_type;
377 
378 	*e++ = 57;		/* Maximum DHCP Message Size */
379 	*e++ = 2;
380 	*e++ = (576 - 312 + OPT_SIZE) >> 8;
381 	*e++ = (576 - 312 + OPT_SIZE) & 0xff;
382 
383 	if (ServerID) {
384 		int tmp = ntohl (ServerID);
385 
386 		*e++ = 54;	/* ServerID */
387 		*e++ = 4;
388 		*e++ = tmp >> 24;
389 		*e++ = tmp >> 16;
390 		*e++ = tmp >> 8;
391 		*e++ = tmp & 0xff;
392 	}
393 
394 	if (RequestedIP) {
395 		int tmp = ntohl (RequestedIP);
396 
397 		*e++ = 50;	/* Requested IP */
398 		*e++ = 4;
399 		*e++ = tmp >> 24;
400 		*e++ = tmp >> 16;
401 		*e++ = tmp >> 8;
402 		*e++ = tmp & 0xff;
403 	}
404 #if defined(CONFIG_BOOTP_SEND_HOSTNAME)
405 	if ((hostname = getenv ("hostname"))) {
406 		int hostnamelen = strlen (hostname);
407 
408 		*e++ = 12;	/* Hostname */
409 		*e++ = hostnamelen;
410 		memcpy (e, hostname, hostnamelen);
411 		e += hostnamelen;
412 	}
413 #endif
414 
415 #if defined(CONFIG_BOOTP_VENDOREX)
416 	if ((x = dhcp_vendorex_prep (e)))
417 		return x - start;
418 #endif
419 
420 	*e++ = 55;		/* Parameter Request List */
421 	 cnt = e++;		/* Pointer to count of requested items */
422 	*cnt = 0;
423 #if defined(CONFIG_BOOTP_SUBNETMASK)
424 	*e++  = 1;		/* Subnet Mask */
425 	*cnt += 1;
426 #endif
427 #if defined(CONFIG_BOOTP_TIMEOFFSET)
428 	*e++  = 2;
429 	*cnt += 1;
430 #endif
431 #if defined(CONFIG_BOOTP_GATEWAY)
432 	*e++  = 3;		/* Router Option */
433 	*cnt += 1;
434 #endif
435 #if defined(CONFIG_BOOTP_DNS)
436 	*e++  = 6;		/* DNS Server(s) */
437 	*cnt += 1;
438 #endif
439 #if defined(CONFIG_BOOTP_HOSTNAME)
440 	*e++  = 12;		/* Hostname */
441 	*cnt += 1;
442 #endif
443 #if defined(CONFIG_BOOTP_BOOTFILESIZE)
444 	*e++  = 13;		/* Boot File Size */
445 	*cnt += 1;
446 #endif
447 #if defined(CONFIG_BOOTP_BOOTPATH)
448 	*e++  = 17;		/* Boot path */
449 	*cnt += 1;
450 #endif
451 #if defined(CONFIG_BOOTP_NISDOMAIN)
452 	*e++  = 40;		/* NIS Domain name request */
453 	*cnt += 1;
454 #endif
455 #if defined(CONFIG_BOOTP_NTPSERVER)
456 	*e++  = 42;
457 	*cnt += 1;
458 #endif
459 	*e++  = 255;		/* End of the list */
460 
461 	/* Pad to minimal length */
462 #ifdef	CONFIG_DHCP_MIN_EXT_LEN
463 	while ((e - start) <= CONFIG_DHCP_MIN_EXT_LEN)
464 		*e++ = 0;
465 #endif
466 
467 	return e - start;
468 }
469 
470 #else
471 /*
472  *	Warning: no field size check - change CONFIG_BOOTP_* at your own risk!
473  */
474 static int BootpExtended (u8 * e)
475 {
476 	u8 *start = e;
477 
478 	*e++ = 99;		/* RFC1048 Magic Cookie */
479 	*e++ = 130;
480 	*e++ = 83;
481 	*e++ = 99;
482 
483 #if defined(CONFIG_CMD_DHCP)
484 	*e++ = 53;		/* DHCP Message Type */
485 	*e++ = 1;
486 	*e++ = DHCP_DISCOVER;
487 
488 	*e++ = 57;		/* Maximum DHCP Message Size */
489 	*e++ = 2;
490 	*e++ = (576 - 312 + OPT_SIZE) >> 16;
491 	*e++ = (576 - 312 + OPT_SIZE) & 0xff;
492 #endif
493 
494 #if defined(CONFIG_BOOTP_SUBNETMASK)
495 	*e++ = 1;		/* Subnet mask request */
496 	*e++ = 4;
497 	e   += 4;
498 #endif
499 
500 #if defined(CONFIG_BOOTP_GATEWAY)
501 	*e++ = 3;		/* Default gateway request */
502 	*e++ = 4;
503 	e   += 4;
504 #endif
505 
506 #if defined(CONFIG_BOOTP_DNS)
507 	*e++ = 6;		/* Domain Name Server */
508 	*e++ = 4;
509 	e   += 4;
510 #endif
511 
512 #if defined(CONFIG_BOOTP_HOSTNAME)
513 	*e++ = 12;		/* Host name request */
514 	*e++ = 32;
515 	e   += 32;
516 #endif
517 
518 #if defined(CONFIG_BOOTP_BOOTFILESIZE)
519 	*e++ = 13;		/* Boot file size */
520 	*e++ = 2;
521 	e   += 2;
522 #endif
523 
524 #if defined(CONFIG_BOOTP_BOOTPATH)
525 	*e++ = 17;		/* Boot path */
526 	*e++ = 32;
527 	e   += 32;
528 #endif
529 
530 #if defined(CONFIG_BOOTP_NISDOMAIN)
531 	*e++ = 40;		/* NIS Domain name request */
532 	*e++ = 32;
533 	e   += 32;
534 #endif
535 
536 	*e++ = 255;		/* End of the list */
537 
538 	return e - start;
539 }
540 #endif
541 
542 void
543 BootpRequest (void)
544 {
545 	volatile uchar *pkt, *iphdr;
546 	Bootp_t *bp;
547 	int ext_len, pktlen, iplen;
548 
549 #if defined(CONFIG_CMD_DHCP)
550 	dhcp_state = INIT;
551 #endif
552 
553 #ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */
554 	unsigned char bi_enetaddr[6];
555 	int   reg;
556 	ulong tst1, tst2, sum, m_mask, m_value = 0;
557 
558 	if (BootpTry ==0) {
559 		/* get our mac */
560 		eth_getenv_enetaddr("ethaddr", bi_enetaddr);
561 
562 		debug("BootpRequest => Our Mac: ");
563 		for (reg=0; reg<6; reg++)
564 			debug("%x%c", bi_enetaddr[reg], reg==5 ? '\n' : ':');
565 
566 		/* Mac-Manipulation 2 get seed1 */
567 		tst1=0;
568 		tst2=0;
569 		for (reg=2; reg<6; reg++) {
570 			tst1 = tst1 << 8;
571 			tst1 = tst1 | bi_enetaddr[reg];
572 		}
573 		for (reg=0; reg<2; reg++) {
574 			tst2 = tst2 | bi_enetaddr[reg];
575 			tst2 = tst2 << 8;
576 		}
577 
578 		seed1 = tst1^tst2;
579 
580 		/* Mirror seed1*/
581 		m_mask=0x1;
582 		for (reg=1;reg<=32;reg++) {
583 			m_value |= (m_mask & seed1);
584 			seed1 = seed1 >> 1;
585 			m_value = m_value << 1;
586 		}
587 		seed1 = m_value;
588 		seed2 = 0xB78D0945;
589 	}
590 
591 	/* Random Number Generator */
592 
593 	for (reg=0;reg<=0;reg++) {
594 		sum = seed1 + seed2;
595 		if (sum < seed1 || sum < seed2)
596 			sum++;
597 		seed2 = seed1;
598 		seed1 = sum;
599 
600 		if (BootpTry<=2) {	/* Start with max 1024 * 1ms */
601 			sum = sum >> (22-BootpTry);
602 		} else {		/*After 3rd BOOTP request max 8192 * 1ms */
603 			sum = sum >> 19;
604 		}
605 	}
606 
607 	printf ("Random delay: %ld ms...\n", sum);
608 	for (reg=0; reg <sum; reg++) {
609 		udelay(1000); /*Wait 1ms*/
610 	}
611 #endif	/* CONFIG_BOOTP_RANDOM_DELAY */
612 
613 	printf("BOOTP broadcast %d\n", ++BootpTry);
614 	pkt = NetTxPacket;
615 	memset ((void*)pkt, 0, PKTSIZE);
616 
617 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);
618 
619 	/*
620 	 * Next line results in incorrect packet size being transmitted, resulting
621 	 * in errors in some DHCP servers, reporting missing bytes.  Size must be
622 	 * set in packet header after extension length has been determined.
623 	 * C. Hallinan, DS4.COM, Inc.
624 	 */
625 	/* NetSetIP(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, sizeof (Bootp_t)); */
626 	iphdr = pkt;	/* We need this later for NetSetIP() */
627 	pkt += IP_HDR_SIZE;
628 
629 	bp = (Bootp_t *)pkt;
630 	bp->bp_op = OP_BOOTREQUEST;
631 	bp->bp_htype = HWT_ETHER;
632 	bp->bp_hlen = HWL_ETHER;
633 	bp->bp_hops = 0;
634 	bp->bp_secs = htons(get_timer(0) / 1000);
635 	NetWriteIP(&bp->bp_ciaddr, 0);
636 	NetWriteIP(&bp->bp_yiaddr, 0);
637 	NetWriteIP(&bp->bp_siaddr, 0);
638 	NetWriteIP(&bp->bp_giaddr, 0);
639 	memcpy (bp->bp_chaddr, NetOurEther, 6);
640 	copy_filename (bp->bp_file, BootFile, sizeof(bp->bp_file));
641 
642 	/* Request additional information from the BOOTP/DHCP server */
643 #if defined(CONFIG_CMD_DHCP)
644 	ext_len = DhcpExtended((u8 *)bp->bp_vend, DHCP_DISCOVER, 0, 0);
645 #else
646 	ext_len = BootpExtended((u8 *)bp->bp_vend);
647 #endif
648 
649 	/*
650 	 *	Bootp ID is the lower 4 bytes of our ethernet address
651 	 *	plus the current time in ms.
652 	 */
653 	BootpID = ((ulong)NetOurEther[2] << 24)
654 		| ((ulong)NetOurEther[3] << 16)
655 		| ((ulong)NetOurEther[4] << 8)
656 		| (ulong)NetOurEther[5];
657 	BootpID += get_timer(0);
658 	BootpID	 = htonl(BootpID);
659 	NetCopyLong(&bp->bp_id, &BootpID);
660 
661 	/*
662 	 * Calculate proper packet lengths taking into account the
663 	 * variable size of the options field
664 	 */
665 	pktlen = ((int)(pkt-NetTxPacket)) + BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
666 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
667 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
668 	NetSetTimeout(SELECT_TIMEOUT, BootpTimeout);
669 
670 #if defined(CONFIG_CMD_DHCP)
671 	dhcp_state = SELECTING;
672 	NetSetHandler(DhcpHandler);
673 #else
674 	NetSetHandler(BootpHandler);
675 #endif
676 	NetSendPacket(NetTxPacket, pktlen);
677 }
678 
679 #if defined(CONFIG_CMD_DHCP)
680 static void DhcpOptionsProcess (uchar * popt, Bootp_t *bp)
681 {
682 	uchar *end = popt + BOOTP_HDR_SIZE;
683 	int oplen, size;
684 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
685 	int *to_ptr;
686 #endif
687 
688 	while (popt < end && *popt != 0xff) {
689 		oplen = *(popt + 1);
690 		switch (*popt) {
691 		case 1:
692 			NetCopyIP (&NetOurSubnetMask, (popt + 2));
693 			break;
694 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
695 		case 2:		/* Time offset	*/
696 			to_ptr = &NetTimeOffset;
697 			NetCopyLong ((ulong *)to_ptr, (ulong *)(popt + 2));
698 			NetTimeOffset = ntohl (NetTimeOffset);
699 			break;
700 #endif
701 		case 3:
702 			NetCopyIP (&NetOurGatewayIP, (popt + 2));
703 			break;
704 		case 6:
705 			NetCopyIP (&NetOurDNSIP, (popt + 2));
706 #if defined(CONFIG_BOOTP_DNS2)
707 			if (*(popt + 1) > 4) {
708 				NetCopyIP (&NetOurDNS2IP, (popt + 2 + 4));
709 			}
710 #endif
711 			break;
712 		case 12:
713 			size = truncate_sz ("Host Name", sizeof (NetOurHostName), oplen);
714 			memcpy (&NetOurHostName, popt + 2, size);
715 			NetOurHostName[size] = 0;
716 			break;
717 		case 15:	/* Ignore Domain Name Option */
718 			break;
719 		case 17:
720 			size = truncate_sz ("Root Path", sizeof (NetOurRootPath), oplen);
721 			memcpy (&NetOurRootPath, popt + 2, size);
722 			NetOurRootPath[size] = 0;
723 			break;
724 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)
725 		case 42:	/* NTP server IP */
726 			NetCopyIP (&NetNtpServerIP, (popt + 2));
727 			break;
728 #endif
729 		case 51:
730 			NetCopyLong (&dhcp_leasetime, (ulong *) (popt + 2));
731 			break;
732 		case 53:	/* Ignore Message Type Option */
733 			break;
734 		case 54:
735 			NetCopyIP (&NetDHCPServerIP, (popt + 2));
736 			break;
737 		case 58:	/* Ignore Renewal Time Option */
738 			break;
739 		case 59:	/* Ignore Rebinding Time Option */
740 			break;
741 		case 66:	/* Ignore TFTP server name */
742 			break;
743 		case 67:	/* vendor opt bootfile */
744 			/*
745 			 * I can't use dhcp_vendorex_proc here because I need
746 			 * to write into the bootp packet - even then I had to
747 			 * pass the bootp packet pointer into here as the
748 			 * second arg
749 			 */
750 			size = truncate_sz ("Opt Boot File",
751 					    sizeof(bp->bp_file),
752 					    oplen);
753 			if (bp->bp_file[0] == '\0' && size > 0) {
754 				/*
755 				 * only use vendor boot file if we didn't
756 				 * receive a boot file in the main non-vendor
757 				 * part of the packet - god only knows why
758 				 * some vendors chose not to use this perfectly
759 				 * good spot to store the boot file (join on
760 				 * Tru64 Unix) it seems mind bogglingly crazy
761 				 * to me
762 				 */
763 				printf("*** WARNING: using vendor "
764 					"optional boot file\n");
765 				memcpy(bp->bp_file, popt + 2, size);
766 				bp->bp_file[size] = '\0';
767 			}
768 			break;
769 		default:
770 #if defined(CONFIG_BOOTP_VENDOREX)
771 			if (dhcp_vendorex_proc (popt))
772 				break;
773 #endif
774 			printf ("*** Unhandled DHCP Option in OFFER/ACK: %d\n", *popt);
775 			break;
776 		}
777 		popt += oplen + 2;	/* Process next option */
778 	}
779 }
780 
781 static int DhcpMessageType(unsigned char *popt)
782 {
783 	if (NetReadLong((ulong*)popt) != htonl(BOOTP_VENDOR_MAGIC))
784 		return -1;
785 
786 	popt += 4;
787 	while ( *popt != 0xff ) {
788 		if ( *popt == 53 )	/* DHCP Message Type */
789 			return *(popt + 2);
790 		popt += *(popt + 1) + 2;	/* Scan through all options */
791 	}
792 	return -1;
793 }
794 
795 static void DhcpSendRequestPkt(Bootp_t *bp_offer)
796 {
797 	volatile uchar *pkt, *iphdr;
798 	Bootp_t *bp;
799 	int pktlen, iplen, extlen;
800 	IPaddr_t OfferedIP;
801 
802 	debug("DhcpSendRequestPkt: Sending DHCPREQUEST\n");
803 	pkt = NetTxPacket;
804 	memset ((void*)pkt, 0, PKTSIZE);
805 
806 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);
807 
808 	iphdr = pkt;		/* We'll need this later to set proper pkt size */
809 	pkt += IP_HDR_SIZE;
810 
811 	bp = (Bootp_t *)pkt;
812 	bp->bp_op = OP_BOOTREQUEST;
813 	bp->bp_htype = HWT_ETHER;
814 	bp->bp_hlen = HWL_ETHER;
815 	bp->bp_hops = 0;
816 	bp->bp_secs = htons(get_timer(0) / 1000);
817 	/* Do not set the client IP, your IP, or server IP yet, since it hasn't been ACK'ed by
818 	 * the server yet */
819 
820 	/*
821 	 * RFC3046 requires Relay Agents to discard packets with
822 	 * nonzero and offered giaddr
823 	 */
824 	NetWriteIP(&bp->bp_giaddr, 0);
825 
826 	memcpy (bp->bp_chaddr, NetOurEther, 6);
827 
828 	/*
829 	 * ID is the id of the OFFER packet
830 	 */
831 
832 	NetCopyLong(&bp->bp_id, &bp_offer->bp_id);
833 
834 	/*
835 	 * Copy options from OFFER packet if present
836 	 */
837 
838 	/* Copy offered IP into the parameters request list */
839 	NetCopyIP(&OfferedIP, &bp_offer->bp_yiaddr);
840 	extlen = DhcpExtended((u8 *)bp->bp_vend, DHCP_REQUEST, NetDHCPServerIP, OfferedIP);
841 
842 	pktlen = ((int)(pkt-NetTxPacket)) + BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
843 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
844 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
845 
846 	debug("Transmitting DHCPREQUEST packet: len = %d\n", pktlen);
847 #ifdef CONFIG_BOOTP_DHCP_REQUEST_DELAY
848 	udelay(CONFIG_BOOTP_DHCP_REQUEST_DELAY);
849 #endif	/* CONFIG_BOOTP_DHCP_REQUEST_DELAY */
850 	NetSendPacket(NetTxPacket, pktlen);
851 }
852 
853 /*
854  *	Handle DHCP received packets.
855  */
856 static void
857 DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
858 {
859 	Bootp_t *bp = (Bootp_t *)pkt;
860 
861 	debug("DHCPHandler: got packet: (src=%d, dst=%d, len=%d) state: %d\n",
862 		src, dest, len, dhcp_state);
863 
864 	if (BootpCheckPkt(pkt, dest, src, len)) /* Filter out pkts we don't want */
865 		return;
866 
867 	debug("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: %d\n",
868 		src, dest, len, dhcp_state);
869 
870 	switch (dhcp_state) {
871 	case SELECTING:
872 		/*
873 		 * Wait an appropriate time for any potential DHCPOFFER packets
874 		 * to arrive.  Then select one, and generate DHCPREQUEST response.
875 		 * If filename is in format we recognize, assume it is a valid
876 		 * OFFER from a server we want.
877 		 */
878 		debug("DHCP: state=SELECTING bp_file: \"%s\"\n", bp->bp_file);
879 #ifdef CONFIG_SYS_BOOTFILE_PREFIX
880 		if (strncmp(bp->bp_file,
881 			    CONFIG_SYS_BOOTFILE_PREFIX,
882 			    strlen(CONFIG_SYS_BOOTFILE_PREFIX)) == 0 ) {
883 #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */
884 
885 			debug("TRANSITIONING TO REQUESTING STATE\n");
886 			dhcp_state = REQUESTING;
887 
888 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
889 				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);
890 
891 			NetSetTimeout(TIMEOUT, BootpTimeout);
892 			DhcpSendRequestPkt(bp);
893 #ifdef CONFIG_SYS_BOOTFILE_PREFIX
894 		}
895 #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */
896 
897 		return;
898 		break;
899 	case REQUESTING:
900 		debug("DHCP State: REQUESTING\n");
901 
902 		if ( DhcpMessageType((u8 *)bp->bp_vend) == DHCP_ACK ) {
903 			char *s;
904 
905 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
906 				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);
907 			BootpCopyNetParams(bp); /* Store net params from reply */
908 			dhcp_state = BOUND;
909 			printf ("DHCP client bound to address %pI4\n", &NetOurIP);
910 
911 			/* Obey the 'autoload' setting */
912 			if ((s = getenv("autoload")) != NULL) {
913 				if (*s == 'n') {
914 					/*
915 					 * Just use BOOTP to configure system;
916 					 * Do not use TFTP to load the bootfile.
917 					 */
918 					NetState = NETLOOP_SUCCESS;
919 					return;
920 #if defined(CONFIG_CMD_NFS)
921 				} else if (strcmp(s, "NFS") == 0) {
922 					/*
923 					 * Use NFS to load the bootfile.
924 					 */
925 					NfsStart();
926 					return;
927 #endif
928 				}
929 			}
930 			TftpStart();
931 			return;
932 		}
933 		break;
934 	case BOUND:
935 		/* DHCP client bound to address */
936 		break;
937 	default:
938 		puts ("DHCP: INVALID STATE\n");
939 		break;
940 	}
941 
942 }
943 
944 void DhcpRequest(void)
945 {
946 	BootpRequest();
947 }
948 #endif	/* CONFIG_CMD_DHCP */
949