xref: /openbmc/u-boot/net/bootp.c (revision a380279b)
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 #if defined(CONFIG_CMD_NET)
24 
25 #define TIMEOUT		5000UL	/* Milliseconds before trying BOOTP again */
26 #ifndef CONFIG_NET_RETRY_COUNT
27 # define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
28 #else
29 # define TIMEOUT_COUNT	(CONFIG_NET_RETRY_COUNT)
30 #endif
31 
32 #define PORT_BOOTPS	67		/* BOOTP server UDP port		*/
33 #define PORT_BOOTPC	68		/* BOOTP client UDP port		*/
34 
35 #ifndef CONFIG_DHCP_MIN_EXT_LEN		/* minimal length of extension list	*/
36 #define CONFIG_DHCP_MIN_EXT_LEN 64
37 #endif
38 
39 ulong		BootpID;
40 int		BootpTry;
41 #ifdef CONFIG_BOOTP_RANDOM_DELAY
42 ulong		seed1, seed2;
43 #endif
44 
45 #if defined(CONFIG_CMD_DHCP)
46 dhcp_state_t dhcp_state = INIT;
47 unsigned long dhcp_leasetime = 0;
48 IPaddr_t NetDHCPServerIP = 0;
49 static void DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len);
50 
51 /* For Debug */
52 #if 0
53 static char *dhcpmsg2str(int type)
54 {
55 	switch (type) {
56 	case 1:	 return "DHCPDISCOVER"; break;
57 	case 2:	 return "DHCPOFFER";	break;
58 	case 3:	 return "DHCPREQUEST";	break;
59 	case 4:	 return "DHCPDECLINE";	break;
60 	case 5:	 return "DHCPACK";	break;
61 	case 6:	 return "DHCPNACK";	break;
62 	case 7:	 return "DHCPRELEASE";	break;
63 	default: return "UNKNOWN/INVALID MSG TYPE"; break;
64 	}
65 }
66 #endif
67 
68 #if defined(CONFIG_BOOTP_VENDOREX)
69 extern u8 *dhcp_vendorex_prep (u8 *e); /*rtn new e after add own opts. */
70 extern u8 *dhcp_vendorex_proc (u8 *e); /*rtn next e if mine,else NULL  */
71 #endif
72 
73 #endif
74 
75 static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
76 {
77 	Bootp_t *bp = (Bootp_t *) pkt;
78 	int retval = 0;
79 
80 	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
81 		retval = -1;
82 	else if (len < sizeof (Bootp_t) - OPT_SIZE)
83 		retval = -2;
84 	else if (bp->bp_op != OP_BOOTREQUEST &&
85 	    bp->bp_op != OP_BOOTREPLY &&
86 	    bp->bp_op != DHCP_OFFER &&
87 	    bp->bp_op != DHCP_ACK &&
88 	    bp->bp_op != DHCP_NAK ) {
89 		retval = -3;
90 	}
91 	else if (bp->bp_htype != HWT_ETHER)
92 		retval = -4;
93 	else if (bp->bp_hlen != HWL_ETHER)
94 		retval = -5;
95 	else if (NetReadLong((ulong*)&bp->bp_id) != BootpID) {
96 		retval = -6;
97 	}
98 
99 	debug("Filtering pkt = %d\n", retval);
100 
101 	return retval;
102 }
103 
104 /*
105  * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
106  */
107 static void BootpCopyNetParams(Bootp_t *bp)
108 {
109 	IPaddr_t tmp_ip;
110 
111 	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);
112 #if !defined(CONFIG_BOOTP_SERVERIP)
113 	NetCopyIP(&tmp_ip, &bp->bp_siaddr);
114 	if (tmp_ip != 0)
115 		NetCopyIP(&NetServerIP, &bp->bp_siaddr);
116 	memcpy (NetServerEther, ((Ethernet_t *)NetRxPacket)->et_src, 6);
117 #endif
118 	if (strlen(bp->bp_file) > 0)
119 		copy_filename (BootFile, bp->bp_file, sizeof(BootFile));
120 
121 	debug("Bootfile: %s\n", BootFile);
122 
123 	/* Propagate to environment:
124 	 * don't delete exising entry when BOOTP / DHCP reply does
125 	 * not contain a new value
126 	 */
127 	if (*BootFile) {
128 		setenv ("bootfile", BootFile);
129 	}
130 }
131 
132 static int truncate_sz (const char *name, int maxlen, int curlen)
133 {
134 	if (curlen >= maxlen) {
135 		printf("*** WARNING: %s is too long (%d - max: %d) - truncated\n",
136 			name, curlen, maxlen);
137 		curlen = maxlen - 1;
138 	}
139 	return (curlen);
140 }
141 
142 #if !defined(CONFIG_CMD_DHCP)
143 
144 static void BootpVendorFieldProcess (u8 * ext)
145 {
146 	int size = *(ext + 1);
147 
148 	debug("[BOOTP] Processing extension %d... (%d bytes)\n", *ext,
149 		   *(ext + 1));
150 
151 	NetBootFileSize = 0;
152 
153 	switch (*ext) {
154 		/* Fixed length fields */
155 	case 1:			/* Subnet mask					*/
156 		if (NetOurSubnetMask == 0)
157 			NetCopyIP (&NetOurSubnetMask, (IPaddr_t *) (ext + 2));
158 		break;
159 	case 2:			/* Time offset - Not yet supported		*/
160 		break;
161 		/* Variable length fields */
162 	case 3:			/* Gateways list				*/
163 		if (NetOurGatewayIP == 0) {
164 			NetCopyIP (&NetOurGatewayIP, (IPaddr_t *) (ext + 2));
165 		}
166 		break;
167 	case 4:			/* Time server - Not yet supported		*/
168 		break;
169 	case 5:			/* IEN-116 name server - Not yet supported	*/
170 		break;
171 	case 6:
172 		if (NetOurDNSIP == 0) {
173 			NetCopyIP (&NetOurDNSIP, (IPaddr_t *) (ext + 2));
174 		}
175 #if defined(CONFIG_BOOTP_DNS2)
176 		if ((NetOurDNS2IP == 0) && (size > 4)) {
177 			NetCopyIP (&NetOurDNS2IP, (IPaddr_t *) (ext + 2 + 4));
178 		}
179 #endif
180 		break;
181 	case 7:			/* Log server - Not yet supported		*/
182 		break;
183 	case 8:			/* Cookie/Quote server - Not yet supported	*/
184 		break;
185 	case 9:			/* LPR server - Not yet supported		*/
186 		break;
187 	case 10:		/* Impress server - Not yet supported		*/
188 		break;
189 	case 11:		/* RPL server - Not yet supported		*/
190 		break;
191 	case 12:		/* Host name					*/
192 		if (NetOurHostName[0] == 0) {
193 			size = truncate_sz ("Host Name", sizeof (NetOurHostName), size);
194 			memcpy (&NetOurHostName, ext + 2, size);
195 			NetOurHostName[size] = 0;
196 		}
197 		break;
198 	case 13:		/* Boot file size				*/
199 		if (size == 2)
200 			NetBootFileSize = ntohs (*(ushort *) (ext + 2));
201 		else if (size == 4)
202 			NetBootFileSize = ntohl (*(ulong *) (ext + 2));
203 		break;
204 	case 14:		/* Merit dump file - Not yet supported		*/
205 		break;
206 	case 15:		/* Domain name - Not yet supported		*/
207 		break;
208 	case 16:		/* Swap server - Not yet supported		*/
209 		break;
210 	case 17:		/* Root path					*/
211 		if (NetOurRootPath[0] == 0) {
212 			size = truncate_sz ("Root Path", sizeof (NetOurRootPath), size);
213 			memcpy (&NetOurRootPath, ext + 2, size);
214 			NetOurRootPath[size] = 0;
215 		}
216 		break;
217 	case 18:		/* Extension path - Not yet supported		*/
218 		/*
219 		 * This can be used to send the information of the
220 		 * vendor area in another file that the client can
221 		 * access via TFTP.
222 		 */
223 		break;
224 		/* IP host layer fields */
225 	case 40:		/* NIS Domain name				*/
226 		if (NetOurNISDomain[0] == 0) {
227 			size = truncate_sz ("NIS Domain Name", sizeof (NetOurNISDomain), size);
228 			memcpy (&NetOurNISDomain, ext + 2, size);
229 			NetOurNISDomain[size] = 0;
230 		}
231 		break;
232 		/* Application layer fields */
233 	case 43:		/* Vendor specific info - Not yet supported	*/
234 		/*
235 		 * Binary information to exchange specific
236 		 * product information.
237 		 */
238 		break;
239 		/* Reserved (custom) fields (128..254) */
240 	}
241 }
242 
243 static void BootpVendorProcess (u8 * ext, int size)
244 {
245 	u8 *end = ext + size;
246 
247 	debug("[BOOTP] Checking extension (%d bytes)...\n", size);
248 
249 	while ((ext < end) && (*ext != 0xff)) {
250 		if (*ext == 0) {
251 			ext++;
252 		} else {
253 			u8 *opt = ext;
254 
255 			ext += ext[1] + 2;
256 			if (ext <= end)
257 				BootpVendorFieldProcess (opt);
258 		}
259 	}
260 
261 	debug("[BOOTP] Received fields: \n");
262 	if (NetOurSubnetMask)
263 		debug("NetOurSubnetMask : %pI4\n", &NetOurSubnetMask);
264 
265 	if (NetOurGatewayIP)
266 		debug("NetOurGatewayIP	: %pI4", &NetOurGatewayIP);
267 
268 	if (NetBootFileSize)
269 		debug("NetBootFileSize : %d\n", NetBootFileSize);
270 
271 	if (NetOurHostName[0])
272 		debug("NetOurHostName  : %s\n", NetOurHostName);
273 
274 	if (NetOurRootPath[0])
275 		debug("NetOurRootPath  : %s\n", NetOurRootPath);
276 
277 	if (NetOurNISDomain[0])
278 		debug("NetOurNISDomain : %s\n", NetOurNISDomain);
279 
280 	if (NetBootFileSize)
281 		debug("NetBootFileSize: %d\n", NetBootFileSize);
282 }
283 /*
284  *	Handle a BOOTP received packet.
285  */
286 static void
287 BootpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
288 {
289 	Bootp_t *bp;
290 	char	*s;
291 
292 	debug("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%zu)\n",
293 		src, dest, len, sizeof (Bootp_t));
294 
295 	bp = (Bootp_t *)pkt;
296 
297 	if (BootpCheckPkt(pkt, dest, src, len)) /* Filter out pkts we don't want */
298 		return;
299 
300 	/*
301 	 *	Got a good BOOTP reply.	 Copy the data into our variables.
302 	 */
303 #ifdef CONFIG_STATUS_LED
304 	status_led_set (STATUS_LED_BOOT, STATUS_LED_OFF);
305 #endif
306 
307 	BootpCopyNetParams(bp);		/* Store net parameters from reply */
308 
309 	/* Retrieve extended information (we must parse the vendor area) */
310 	if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
311 		BootpVendorProcess((uchar *)&bp->bp_vend[4], len);
312 
313 	NetSetTimeout(0, (thand_f *)0);
314 
315 	debug("Got good BOOTP\n");
316 
317 	if ((s = getenv("autoload")) != NULL) {
318 		if (*s == 'n') {
319 			/*
320 			 * Just use BOOTP to configure system;
321 			 * Do not use TFTP to load the bootfile.
322 			 */
323 			NetState = NETLOOP_SUCCESS;
324 			return;
325 #if defined(CONFIG_CMD_NFS)
326 		} else if (strcmp(s, "NFS") == 0) {
327 			/*
328 			 * Use NFS to load the bootfile.
329 			 */
330 			NfsStart();
331 			return;
332 #endif
333 		}
334 	}
335 
336 	TftpStart();
337 }
338 #endif
339 
340 /*
341  *	Timeout on BOOTP/DHCP request.
342  */
343 static void
344 BootpTimeout(void)
345 {
346 	if (BootpTry >= TIMEOUT_COUNT) {
347 		puts ("\nRetry count exceeded; starting again\n");
348 		NetStartAgain ();
349 	} else {
350 		NetSetTimeout (TIMEOUT, BootpTimeout);
351 		BootpRequest ();
352 	}
353 }
354 
355 /*
356  *	Initialize BOOTP extension fields in the request.
357  */
358 #if defined(CONFIG_CMD_DHCP)
359 static int DhcpExtended (u8 * e, int message_type, IPaddr_t ServerID, IPaddr_t RequestedIP)
360 {
361 	u8 *start = e;
362 	u8 *cnt;
363 
364 #if defined(CONFIG_BOOTP_VENDOREX)
365 	u8 *x;
366 #endif
367 #if defined(CONFIG_BOOTP_SEND_HOSTNAME)
368 	char *hostname;
369 #endif
370 
371 	*e++ = 99;		/* RFC1048 Magic Cookie */
372 	*e++ = 130;
373 	*e++ = 83;
374 	*e++ = 99;
375 
376 	*e++ = 53;		/* DHCP Message Type */
377 	*e++ = 1;
378 	*e++ = message_type;
379 
380 	*e++ = 57;		/* Maximum DHCP Message Size */
381 	*e++ = 2;
382 	*e++ = (576 - 312 + OPT_SIZE) >> 8;
383 	*e++ = (576 - 312 + OPT_SIZE) & 0xff;
384 
385 	if (ServerID) {
386 		int tmp = ntohl (ServerID);
387 
388 		*e++ = 54;	/* ServerID */
389 		*e++ = 4;
390 		*e++ = tmp >> 24;
391 		*e++ = tmp >> 16;
392 		*e++ = tmp >> 8;
393 		*e++ = tmp & 0xff;
394 	}
395 
396 	if (RequestedIP) {
397 		int tmp = ntohl (RequestedIP);
398 
399 		*e++ = 50;	/* Requested IP */
400 		*e++ = 4;
401 		*e++ = tmp >> 24;
402 		*e++ = tmp >> 16;
403 		*e++ = tmp >> 8;
404 		*e++ = tmp & 0xff;
405 	}
406 #if defined(CONFIG_BOOTP_SEND_HOSTNAME)
407 	if ((hostname = getenv ("hostname"))) {
408 		int hostnamelen = strlen (hostname);
409 
410 		*e++ = 12;	/* Hostname */
411 		*e++ = hostnamelen;
412 		memcpy (e, hostname, hostnamelen);
413 		e += hostnamelen;
414 	}
415 #endif
416 
417 #if defined(CONFIG_BOOTP_VENDOREX)
418 	if ((x = dhcp_vendorex_prep (e)))
419 		return x - start;
420 #endif
421 
422 	*e++ = 55;		/* Parameter Request List */
423 	 cnt = e++;		/* Pointer to count of requested items */
424 	*cnt = 0;
425 #if defined(CONFIG_BOOTP_SUBNETMASK)
426 	*e++  = 1;		/* Subnet Mask */
427 	*cnt += 1;
428 #endif
429 #if defined(CONFIG_BOOTP_TIMEOFFSET)
430 	*e++  = 2;
431 	*cnt += 1;
432 #endif
433 #if defined(CONFIG_BOOTP_GATEWAY)
434 	*e++  = 3;		/* Router Option */
435 	*cnt += 1;
436 #endif
437 #if defined(CONFIG_BOOTP_DNS)
438 	*e++  = 6;		/* DNS Server(s) */
439 	*cnt += 1;
440 #endif
441 #if defined(CONFIG_BOOTP_HOSTNAME)
442 	*e++  = 12;		/* Hostname */
443 	*cnt += 1;
444 #endif
445 #if defined(CONFIG_BOOTP_BOOTFILESIZE)
446 	*e++  = 13;		/* Boot File Size */
447 	*cnt += 1;
448 #endif
449 #if defined(CONFIG_BOOTP_BOOTPATH)
450 	*e++  = 17;		/* Boot path */
451 	*cnt += 1;
452 #endif
453 #if defined(CONFIG_BOOTP_NISDOMAIN)
454 	*e++  = 40;		/* NIS Domain name request */
455 	*cnt += 1;
456 #endif
457 #if defined(CONFIG_BOOTP_NTPSERVER)
458 	*e++  = 42;
459 	*cnt += 1;
460 #endif
461 	*e++  = 255;		/* End of the list */
462 
463 	/* Pad to minimal length */
464 #ifdef	CONFIG_DHCP_MIN_EXT_LEN
465 	while ((e - start) <= CONFIG_DHCP_MIN_EXT_LEN)
466 		*e++ = 0;
467 #endif
468 
469 	return e - start;
470 }
471 
472 #else
473 /*
474  *	Warning: no field size check - change CONFIG_BOOTP_* at your own risk!
475  */
476 static int BootpExtended (u8 * e)
477 {
478 	u8 *start = e;
479 
480 	*e++ = 99;		/* RFC1048 Magic Cookie */
481 	*e++ = 130;
482 	*e++ = 83;
483 	*e++ = 99;
484 
485 #if defined(CONFIG_CMD_DHCP)
486 	*e++ = 53;		/* DHCP Message Type */
487 	*e++ = 1;
488 	*e++ = DHCP_DISCOVER;
489 
490 	*e++ = 57;		/* Maximum DHCP Message Size */
491 	*e++ = 2;
492 	*e++ = (576 - 312 + OPT_SIZE) >> 16;
493 	*e++ = (576 - 312 + OPT_SIZE) & 0xff;
494 #endif
495 
496 #if defined(CONFIG_BOOTP_SUBNETMASK)
497 	*e++ = 1;		/* Subnet mask request */
498 	*e++ = 4;
499 	e   += 4;
500 #endif
501 
502 #if defined(CONFIG_BOOTP_GATEWAY)
503 	*e++ = 3;		/* Default gateway request */
504 	*e++ = 4;
505 	e   += 4;
506 #endif
507 
508 #if defined(CONFIG_BOOTP_DNS)
509 	*e++ = 6;		/* Domain Name Server */
510 	*e++ = 4;
511 	e   += 4;
512 #endif
513 
514 #if defined(CONFIG_BOOTP_HOSTNAME)
515 	*e++ = 12;		/* Host name request */
516 	*e++ = 32;
517 	e   += 32;
518 #endif
519 
520 #if defined(CONFIG_BOOTP_BOOTFILESIZE)
521 	*e++ = 13;		/* Boot file size */
522 	*e++ = 2;
523 	e   += 2;
524 #endif
525 
526 #if defined(CONFIG_BOOTP_BOOTPATH)
527 	*e++ = 17;		/* Boot path */
528 	*e++ = 32;
529 	e   += 32;
530 #endif
531 
532 #if defined(CONFIG_BOOTP_NISDOMAIN)
533 	*e++ = 40;		/* NIS Domain name request */
534 	*e++ = 32;
535 	e   += 32;
536 #endif
537 
538 	*e++ = 255;		/* End of the list */
539 
540 	return e - start;
541 }
542 #endif
543 
544 void
545 BootpRequest (void)
546 {
547 	volatile uchar *pkt, *iphdr;
548 	Bootp_t *bp;
549 	int ext_len, pktlen, iplen;
550 
551 #if defined(CONFIG_CMD_DHCP)
552 	dhcp_state = INIT;
553 #endif
554 
555 #ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */
556 	unsigned char bi_enetaddr[6];
557 	int   reg;
558 	ulong tst1, tst2, sum, m_mask, m_value = 0;
559 
560 	if (BootpTry ==0) {
561 		/* get our mac */
562 		eth_getenv_enetaddr("ethaddr", bi_enetaddr);
563 
564 		debug("BootpRequest => Our Mac: ");
565 		for (reg=0; reg<6; reg++)
566 			debug("%x%c", bi_enetaddr[reg], reg==5 ? '\n' : ':');
567 
568 		/* Mac-Manipulation 2 get seed1 */
569 		tst1=0;
570 		tst2=0;
571 		for (reg=2; reg<6; reg++) {
572 			tst1 = tst1 << 8;
573 			tst1 = tst1 | bi_enetaddr[reg];
574 		}
575 		for (reg=0; reg<2; reg++) {
576 			tst2 = tst2 | bi_enetaddr[reg];
577 			tst2 = tst2 << 8;
578 		}
579 
580 		seed1 = tst1^tst2;
581 
582 		/* Mirror seed1*/
583 		m_mask=0x1;
584 		for (reg=1;reg<=32;reg++) {
585 			m_value |= (m_mask & seed1);
586 			seed1 = seed1 >> 1;
587 			m_value = m_value << 1;
588 		}
589 		seed1 = m_value;
590 		seed2 = 0xB78D0945;
591 	}
592 
593 	/* Random Number Generator */
594 
595 	for (reg=0;reg<=0;reg++) {
596 		sum = seed1 + seed2;
597 		if (sum < seed1 || sum < seed2)
598 			sum++;
599 		seed2 = seed1;
600 		seed1 = sum;
601 
602 		if (BootpTry<=2) {	/* Start with max 1024 * 1ms */
603 			sum = sum >> (22-BootpTry);
604 		} else {		/*After 3rd BOOTP request max 8192 * 1ms */
605 			sum = sum >> 19;
606 		}
607 	}
608 
609 	printf ("Random delay: %ld ms...\n", sum);
610 	for (reg=0; reg <sum; reg++) {
611 		udelay(1000); /*Wait 1ms*/
612 	}
613 #endif	/* CONFIG_BOOTP_RANDOM_DELAY */
614 
615 	printf("BOOTP broadcast %d\n", ++BootpTry);
616 	pkt = NetTxPacket;
617 	memset ((void*)pkt, 0, PKTSIZE);
618 
619 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);
620 
621 	/*
622 	 * Next line results in incorrect packet size being transmitted, resulting
623 	 * in errors in some DHCP servers, reporting missing bytes.  Size must be
624 	 * set in packet header after extension length has been determined.
625 	 * C. Hallinan, DS4.COM, Inc.
626 	 */
627 	/* NetSetIP(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, sizeof (Bootp_t)); */
628 	iphdr = pkt;	/* We need this later for NetSetIP() */
629 	pkt += IP_HDR_SIZE;
630 
631 	bp = (Bootp_t *)pkt;
632 	bp->bp_op = OP_BOOTREQUEST;
633 	bp->bp_htype = HWT_ETHER;
634 	bp->bp_hlen = HWL_ETHER;
635 	bp->bp_hops = 0;
636 	bp->bp_secs = htons(get_timer(0) / 1000);
637 	NetWriteIP(&bp->bp_ciaddr, 0);
638 	NetWriteIP(&bp->bp_yiaddr, 0);
639 	NetWriteIP(&bp->bp_siaddr, 0);
640 	NetWriteIP(&bp->bp_giaddr, 0);
641 	memcpy (bp->bp_chaddr, NetOurEther, 6);
642 	copy_filename (bp->bp_file, BootFile, sizeof(bp->bp_file));
643 
644 	/* Request additional information from the BOOTP/DHCP server */
645 #if defined(CONFIG_CMD_DHCP)
646 	ext_len = DhcpExtended((u8 *)bp->bp_vend, DHCP_DISCOVER, 0, 0);
647 #else
648 	ext_len = BootpExtended((u8 *)bp->bp_vend);
649 #endif
650 
651 	/*
652 	 *	Bootp ID is the lower 4 bytes of our ethernet address
653 	 *	plus the current time in ms.
654 	 */
655 	BootpID = ((ulong)NetOurEther[2] << 24)
656 		| ((ulong)NetOurEther[3] << 16)
657 		| ((ulong)NetOurEther[4] << 8)
658 		| (ulong)NetOurEther[5];
659 	BootpID += get_timer(0);
660 	BootpID	 = htonl(BootpID);
661 	NetCopyLong(&bp->bp_id, &BootpID);
662 
663 	/*
664 	 * Calculate proper packet lengths taking into account the
665 	 * variable size of the options field
666 	 */
667 	pktlen = ((int)(pkt-NetTxPacket)) + BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
668 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
669 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
670 	NetSetTimeout(SELECT_TIMEOUT, BootpTimeout);
671 
672 #if defined(CONFIG_CMD_DHCP)
673 	dhcp_state = SELECTING;
674 	NetSetHandler(DhcpHandler);
675 #else
676 	NetSetHandler(BootpHandler);
677 #endif
678 	NetSendPacket(NetTxPacket, pktlen);
679 }
680 
681 #if defined(CONFIG_CMD_DHCP)
682 static void DhcpOptionsProcess (uchar * popt, Bootp_t *bp)
683 {
684 	uchar *end = popt + BOOTP_HDR_SIZE;
685 	int oplen, size;
686 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
687 	int *to_ptr;
688 #endif
689 
690 	while (popt < end && *popt != 0xff) {
691 		oplen = *(popt + 1);
692 		switch (*popt) {
693 		case 1:
694 			NetCopyIP (&NetOurSubnetMask, (popt + 2));
695 			break;
696 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_TIMEOFFSET)
697 		case 2:		/* Time offset	*/
698 			to_ptr = &NetTimeOffset;
699 			NetCopyLong ((ulong *)to_ptr, (ulong *)(popt + 2));
700 			NetTimeOffset = ntohl (NetTimeOffset);
701 			break;
702 #endif
703 		case 3:
704 			NetCopyIP (&NetOurGatewayIP, (popt + 2));
705 			break;
706 		case 6:
707 			NetCopyIP (&NetOurDNSIP, (popt + 2));
708 #if defined(CONFIG_BOOTP_DNS2)
709 			if (*(popt + 1) > 4) {
710 				NetCopyIP (&NetOurDNS2IP, (popt + 2 + 4));
711 			}
712 #endif
713 			break;
714 		case 12:
715 			size = truncate_sz ("Host Name", sizeof (NetOurHostName), oplen);
716 			memcpy (&NetOurHostName, popt + 2, size);
717 			NetOurHostName[size] = 0;
718 			break;
719 		case 15:	/* Ignore Domain Name Option */
720 			break;
721 		case 17:
722 			size = truncate_sz ("Root Path", sizeof (NetOurRootPath), oplen);
723 			memcpy (&NetOurRootPath, popt + 2, size);
724 			NetOurRootPath[size] = 0;
725 			break;
726 #if defined(CONFIG_CMD_SNTP) && defined(CONFIG_BOOTP_NTPSERVER)
727 		case 42:	/* NTP server IP */
728 			NetCopyIP (&NetNtpServerIP, (popt + 2));
729 			break;
730 #endif
731 		case 51:
732 			NetCopyLong (&dhcp_leasetime, (ulong *) (popt + 2));
733 			break;
734 		case 53:	/* Ignore Message Type Option */
735 			break;
736 		case 54:
737 			NetCopyIP (&NetDHCPServerIP, (popt + 2));
738 			break;
739 		case 58:	/* Ignore Renewal Time Option */
740 			break;
741 		case 59:	/* Ignore Rebinding Time Option */
742 			break;
743 		case 66:	/* Ignore TFTP server name */
744 			break;
745 		case 67:	/* vendor opt bootfile */
746 			/*
747 			 * I can't use dhcp_vendorex_proc here because I need
748 			 * to write into the bootp packet - even then I had to
749 			 * pass the bootp packet pointer into here as the
750 			 * second arg
751 			 */
752 			size = truncate_sz ("Opt Boot File",
753 					    sizeof(bp->bp_file),
754 					    oplen);
755 			if (bp->bp_file[0] == '\0' && size > 0) {
756 				/*
757 				 * only use vendor boot file if we didn't
758 				 * receive a boot file in the main non-vendor
759 				 * part of the packet - god only knows why
760 				 * some vendors chose not to use this perfectly
761 				 * good spot to store the boot file (join on
762 				 * Tru64 Unix) it seems mind bogglingly crazy
763 				 * to me
764 				 */
765 				printf("*** WARNING: using vendor "
766 					"optional boot file\n");
767 				memcpy(bp->bp_file, popt + 2, size);
768 				bp->bp_file[size] = '\0';
769 			}
770 			break;
771 		default:
772 #if defined(CONFIG_BOOTP_VENDOREX)
773 			if (dhcp_vendorex_proc (popt))
774 				break;
775 #endif
776 			printf ("*** Unhandled DHCP Option in OFFER/ACK: %d\n", *popt);
777 			break;
778 		}
779 		popt += oplen + 2;	/* Process next option */
780 	}
781 }
782 
783 static int DhcpMessageType(unsigned char *popt)
784 {
785 	if (NetReadLong((ulong*)popt) != htonl(BOOTP_VENDOR_MAGIC))
786 		return -1;
787 
788 	popt += 4;
789 	while ( *popt != 0xff ) {
790 		if ( *popt == 53 )	/* DHCP Message Type */
791 			return *(popt + 2);
792 		popt += *(popt + 1) + 2;	/* Scan through all options */
793 	}
794 	return -1;
795 }
796 
797 static void DhcpSendRequestPkt(Bootp_t *bp_offer)
798 {
799 	volatile uchar *pkt, *iphdr;
800 	Bootp_t *bp;
801 	int pktlen, iplen, extlen;
802 	IPaddr_t OfferedIP;
803 
804 	debug("DhcpSendRequestPkt: Sending DHCPREQUEST\n");
805 	pkt = NetTxPacket;
806 	memset ((void*)pkt, 0, PKTSIZE);
807 
808 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_IP);
809 
810 	iphdr = pkt;		/* We'll need this later to set proper pkt size */
811 	pkt += IP_HDR_SIZE;
812 
813 	bp = (Bootp_t *)pkt;
814 	bp->bp_op = OP_BOOTREQUEST;
815 	bp->bp_htype = HWT_ETHER;
816 	bp->bp_hlen = HWL_ETHER;
817 	bp->bp_hops = 0;
818 	bp->bp_secs = htons(get_timer(0) / 1000);
819 	/* Do not set the client IP, your IP, or server IP yet, since it hasn't been ACK'ed by
820 	 * the server yet */
821 
822 	/*
823 	 * RFC3046 requires Relay Agents to discard packets with
824 	 * nonzero and offered giaddr
825 	 */
826 	NetWriteIP(&bp->bp_giaddr, 0);
827 
828 	memcpy (bp->bp_chaddr, NetOurEther, 6);
829 
830 	/*
831 	 * ID is the id of the OFFER packet
832 	 */
833 
834 	NetCopyLong(&bp->bp_id, &bp_offer->bp_id);
835 
836 	/*
837 	 * Copy options from OFFER packet if present
838 	 */
839 
840 	/* Copy offered IP into the parameters request list */
841 	NetCopyIP(&OfferedIP, &bp_offer->bp_yiaddr);
842 	extlen = DhcpExtended((u8 *)bp->bp_vend, DHCP_REQUEST, NetDHCPServerIP, OfferedIP);
843 
844 	pktlen = ((int)(pkt-NetTxPacket)) + BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
845 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
846 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
847 
848 	debug("Transmitting DHCPREQUEST packet: len = %d\n", pktlen);
849 #ifdef CONFIG_BOOTP_DHCP_REQUEST_DELAY
850 	udelay(CONFIG_BOOTP_DHCP_REQUEST_DELAY);
851 #endif	/* CONFIG_BOOTP_DHCP_REQUEST_DELAY */
852 	NetSendPacket(NetTxPacket, pktlen);
853 }
854 
855 /*
856  *	Handle DHCP received packets.
857  */
858 static void
859 DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
860 {
861 	Bootp_t *bp = (Bootp_t *)pkt;
862 
863 	debug("DHCPHandler: got packet: (src=%d, dst=%d, len=%d) state: %d\n",
864 		src, dest, len, dhcp_state);
865 
866 	if (BootpCheckPkt(pkt, dest, src, len)) /* Filter out pkts we don't want */
867 		return;
868 
869 	debug("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: %d\n",
870 		src, dest, len, dhcp_state);
871 
872 	switch (dhcp_state) {
873 	case SELECTING:
874 		/*
875 		 * Wait an appropriate time for any potential DHCPOFFER packets
876 		 * to arrive.  Then select one, and generate DHCPREQUEST response.
877 		 * If filename is in format we recognize, assume it is a valid
878 		 * OFFER from a server we want.
879 		 */
880 		debug("DHCP: state=SELECTING bp_file: \"%s\"\n", bp->bp_file);
881 #ifdef CONFIG_SYS_BOOTFILE_PREFIX
882 		if (strncmp(bp->bp_file,
883 			    CONFIG_SYS_BOOTFILE_PREFIX,
884 			    strlen(CONFIG_SYS_BOOTFILE_PREFIX)) == 0 ) {
885 #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */
886 
887 			debug("TRANSITIONING TO REQUESTING STATE\n");
888 			dhcp_state = REQUESTING;
889 
890 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
891 				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);
892 
893 			NetSetTimeout(TIMEOUT, BootpTimeout);
894 			DhcpSendRequestPkt(bp);
895 #ifdef CONFIG_SYS_BOOTFILE_PREFIX
896 		}
897 #endif	/* CONFIG_SYS_BOOTFILE_PREFIX */
898 
899 		return;
900 		break;
901 	case REQUESTING:
902 		debug("DHCP State: REQUESTING\n");
903 
904 		if ( DhcpMessageType((u8 *)bp->bp_vend) == DHCP_ACK ) {
905 			char *s;
906 
907 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
908 				DhcpOptionsProcess((u8 *)&bp->bp_vend[4], bp);
909 			BootpCopyNetParams(bp); /* Store net params from reply */
910 			dhcp_state = BOUND;
911 			printf ("DHCP client bound to address %pI4\n", &NetOurIP);
912 
913 			/* Obey the 'autoload' setting */
914 			if ((s = getenv("autoload")) != NULL) {
915 				if (*s == 'n') {
916 					/*
917 					 * Just use BOOTP to configure system;
918 					 * Do not use TFTP to load the bootfile.
919 					 */
920 					NetState = NETLOOP_SUCCESS;
921 					return;
922 #if defined(CONFIG_CMD_NFS)
923 				} else if (strcmp(s, "NFS") == 0) {
924 					/*
925 					 * Use NFS to load the bootfile.
926 					 */
927 					NfsStart();
928 					return;
929 #endif
930 				}
931 			}
932 			TftpStart();
933 			return;
934 		}
935 		break;
936 	case BOUND:
937 		/* DHCP client bound to address */
938 		break;
939 	default:
940 		puts ("DHCP: INVALID STATE\n");
941 		break;
942 	}
943 
944 }
945 
946 void DhcpRequest(void)
947 {
948 	BootpRequest();
949 }
950 #endif	/* CONFIG_CMD_DHCP */
951 
952 #endif	/* CONFIG_CMD_NET */
953