xref: /rk3399_rockchip-uboot/net/bootp.c (revision 759a51b4f3ab43c9d845eb1968d20e2a697c2184)
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 2000-2002 Wolfgang Denk, wd@denx.de
9  */
10 
11 #if 0
12 #define	DEBUG		1	/* general debug */
13 #define DEBUG_BOOTP_EXT	1	/* Debug received vendor fields	*/
14 #endif
15 
16 #ifdef DEBUG_BOOTP_EXT
17 #define debug_ext(fmt,args...)	printf (fmt ,##args)
18 #else
19 #define debug_ext(fmt,args...)
20 #endif
21 
22 #include <common.h>
23 #include <command.h>
24 #include <net.h>
25 #include "bootp.h"
26 #include "tftp.h"
27 #include "arp.h"
28 #ifdef CONFIG_STATUS_LED
29 #include <status_led.h>
30 #endif
31 
32 #define	BOOTP_VENDOR_MAGIC	0x63825363 	/* RFC1048 Magic Cookie 	*/
33 
34 #if (CONFIG_COMMANDS & CFG_CMD_NET)
35 
36 #define TIMEOUT		5		/* Seconds before trying BOOTP again	*/
37 #ifndef	CONFIG_NET_RETRY_COUNT
38 # define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
39 #else
40 # define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
41 #endif
42 
43 #define PORT_BOOTPS	67		/* BOOTP server UDP port		*/
44 #define PORT_BOOTPC	68		/* BOOTP client UDP port		*/
45 
46 #ifndef CONFIG_DHCP_MIN_EXT_LEN		/* minimal length of extension list	*/
47 #define	CONFIG_DHCP_MIN_EXT_LEN	64
48 #endif
49 
50 ulong		BootpID;
51 int		BootpTry;
52 #ifdef CONFIG_BOOTP_RANDOM_DELAY
53 ulong		seed1, seed2;
54 #endif
55 
56 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
57 dhcp_state_t dhcp_state = INIT;
58 unsigned int dhcp_leasetime = 0;
59 IPaddr_t NetDHCPServerIP = 0;
60 static void DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len);
61 
62 /* For Debug */
63 #if 0
64 static char *dhcpmsg2str(int type)
65 {
66 	switch (type) {
67 	case 1:  return "DHCPDISCOVER";	break;
68 	case 2:  return "DHCPOFFER";	break;
69 	case 3:  return "DHCPREQUEST";	break;
70 	case 4:  return "DHCPDECLINE";	break;
71 	case 5:  return "DHCPACK";	break;
72 	case 6:  return "DHCPNACK";	break;
73 	case 7:  return "DHCPRELEASE";	break;
74 	default: return "UNKNOWN/INVALID MSG TYPE"; break;
75 	}
76 }
77 #endif
78 
79 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
80 extern u8 *dhcp_vendorex_prep (u8 *e); /*rtn new e after add own opts. */
81 extern u8 *dhcp_vendorex_proc (u8 *e); /*rtn next e if mine,else NULL  */
82 #endif
83 
84 #endif	/* CFG_CMD_DHCP */
85 
86 static int BootpCheckPkt(uchar *pkt, unsigned dest, unsigned src, unsigned len)
87 {
88 	Bootp_t *bp = (Bootp_t *) pkt;
89 	int retval = 0;
90 
91 	if (dest != PORT_BOOTPC || src != PORT_BOOTPS)
92 		retval = -1;
93 	else if (len < sizeof (Bootp_t) - OPT_SIZE)
94 		retval = -2;
95 	else if (bp->bp_op != OP_BOOTREQUEST &&
96 	    bp->bp_op != OP_BOOTREPLY &&
97 	    bp->bp_op != DHCP_OFFER &&
98 	    bp->bp_op != DHCP_ACK &&
99 	    bp->bp_op != DHCP_NAK ) {
100 		retval = -3;
101 	}
102 	else if (bp->bp_htype != HWT_ETHER)
103 		retval = -4;
104 	else if (bp->bp_hlen != HWL_ETHER)
105 		retval = -5;
106 	else if (NetReadLong((ulong*)&bp->bp_id) != BootpID) {
107 		retval = -6;
108 	}
109 
110 	debug ("Filtering pkt = %d\n", retval);
111 
112 	return retval;
113 }
114 
115 /*
116  * Copy parameters of interest from BOOTP_REPLY/DHCP_OFFER packet
117  */
118 static void BootpCopyNetParams(Bootp_t *bp)
119 {
120 	NetCopyIP(&NetOurIP, &bp->bp_yiaddr);
121 	NetCopyIP(&NetServerIP, &bp->bp_siaddr);
122 	memcpy (NetServerEther, ((Ethernet_t *)NetRxPkt)->et_src, 6);
123 	copy_filename (BootFile, bp->bp_file, sizeof(BootFile));
124 
125 	debug ("Bootfile: %s\n", BootFile);
126 
127 	/* Propagate to environment:
128          * don't delete exising entry when BOOTP / DHCP reply does
129 	 * not contain a new value
130 	 */
131 	if (*BootFile) {
132 		setenv ("bootfile", BootFile);
133 	}
134 }
135 
136 static int truncate_sz (const char *name, int maxlen, int curlen)
137 {
138 	if (curlen >= maxlen) {
139 		printf("*** WARNING: %s is too long (%d - max: %d) - truncated\n",
140 			name, curlen, maxlen);
141 		curlen = maxlen - 1;
142 	}
143 	return (curlen);
144 }
145 
146 #if !(CONFIG_COMMANDS & CFG_CMD_DHCP)
147 
148 static void BootpVendorFieldProcess(u8 *ext)
149 {
150     int size = *(ext+1) ;
151 
152     debug_ext ("[BOOTP] Processing extension %d... (%d bytes)\n", *ext, *(ext+1));
153 
154     NetBootFileSize = 0;
155 
156     switch (*ext) {
157     /* Fixed length fields */
158 	case 1:		/* Subnet mask					*/
159 		if (NetOurSubnetMask == 0)
160 			NetCopyIP(&NetOurSubnetMask, (IPaddr_t*)(ext+2));
161 		break;
162 	case 2:		/* Time offset - Not yet supported		*/
163 		break;
164     /* Variable length fields */
165 	case 3:		/* Gateways list				*/
166 		if (NetOurGatewayIP == 0) {
167 			NetCopyIP(&NetOurGatewayIP, (IPaddr_t*)(ext+2));
168 		}
169 		break;
170 	case 4:		/* Time server - Not yet supported		*/
171 		break;
172 	case 5:		/* IEN-116 name server - Not yet supported	*/
173 		break;
174 	case 6:
175 		if (NetOurDNSIP == 0) {
176 			NetCopyIP(&NetOurDNSIP, (IPaddr_t*)(ext+2));
177 		}
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",
226 		    			sizeof(NetOurNISDomain),
227 					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_ext ("[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 		ext += ext[1] + 2 ;
255 		if (ext <= end)
256 		    BootpVendorFieldProcess (opt) ;
257 	}
258     }
259 
260 #ifdef DEBUG_BOOTP_EXT
261     printf("[BOOTP] Received fields: \n");
262     if (NetOurSubnetMask) {
263 	puts ("NetOurSubnetMask	: ");
264 	print_IPaddr (NetOurSubnetMask);
265 	putc('\n');
266     }
267 
268     if (NetOurGatewayIP) {
269 	puts ("NetOurGatewayIP	: ");
270 	print_IPaddr (NetOurGatewayIP);
271 	putc('\n');
272     }
273 
274     if (NetBootFileSize) {
275 	printf("NetBootFileSize : %d\n", NetBootFileSize);
276     }
277 
278     if (NetOurHostName[0]) {
279 	printf("NetOurHostName  : %s\n", NetOurHostName);
280     }
281 
282     if (NetOurRootPath[0]) {
283 	printf("NetOurRootPath  : %s\n", NetOurRootPath);
284     }
285 
286     if (NetOurNISDomain[0]) {
287         printf("NetOurNISDomain : %s\n", NetOurNISDomain);
288     }
289 
290     if (NetBootFileSize) {
291 	printf("NetBootFileSize: %d\n", NetBootFileSize);
292     }
293 #endif	/* DEBUG_BOOTP_EXT */
294 }
295 
296 /*
297  *	Handle a BOOTP received packet.
298  */
299 static void
300 BootpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
301 {
302 	Bootp_t *bp;
303 	char	*s;
304 
305 	debug ("got BOOTP packet (src=%d, dst=%d, len=%d want_len=%d)\n",
306 		src, dest, len, sizeof (Bootp_t));
307 
308 	bp = (Bootp_t *)pkt;
309 
310 	if (BootpCheckPkt(pkt, dest, src, len))	/* Filter out pkts we don't want */
311 		return;
312 
313 	/*
314 	 *	Got a good BOOTP reply.  Copy the data into our variables.
315 	 */
316 #ifdef CONFIG_STATUS_LED
317 	status_led_set (STATUS_LED_BOOT, STATUS_LED_OFF);
318 #endif
319 
320 	BootpCopyNetParams(bp);		/* Store net parameters from reply */
321 
322 	/* Retrieve extended information (we must parse the vendor area) */
323 	if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
324 		BootpVendorProcess(&bp->bp_vend[4], len);
325 
326 	NetSetTimeout(0, (thand_f *)0);
327 
328 	debug ("Got good BOOTP\n");
329 
330 	if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
331 		/*
332 		 * Just use BOOTP to configure system;
333 		 * Do not use TFTP to load the bootfile.
334 		 */
335 		NetState = NETLOOP_SUCCESS;
336 		return;
337 	}
338 
339 	/* Send ARP request to get TFTP server ethernet address.
340 	 * This automagically starts TFTP, too.
341 	 */
342 	ArpRequest();
343 }
344 #endif	/* !CFG_CMD_DHCP */
345 
346 /*
347  *	Timeout on BOOTP/DHCP request.
348  */
349 static void
350 BootpTimeout(void)
351 {
352 	if (BootpTry >= TIMEOUT_COUNT) {
353 		puts ("\nRetry count exceeded; starting again\n");
354 		NetStartAgain ();
355 	} else {
356 		NetSetTimeout (TIMEOUT * CFG_HZ, BootpTimeout);
357 		BootpRequest ();
358 	}
359 }
360 
361 /*
362  *	Initialize BOOTP extension fields in the request.
363  */
364 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
365 static int DhcpExtended(u8 *e, int message_type, IPaddr_t ServerID, IPaddr_t RequestedIP)
366 {
367     u8 *start = e ;
368     u8 *cnt;
369 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
370     u8 *x;
371 #endif
372 
373     *e++ =  99;		/* RFC1048 Magic Cookie */
374     *e++ = 130;
375     *e++ =  83;
376     *e++ =  99;
377 
378     *e++ = 53;		/* DHCP Message Type */
379     *e++ = 1;
380     *e++ = message_type;
381 
382     *e++ = 57;		/* Maximum DHCP Message Size */
383     *e++ = 2;
384     *e++ = (576-312+OPT_SIZE) >> 8;
385     *e++ = (576-312+OPT_SIZE) & 0xff;
386 
387     if ( ServerID ) {
388     	    int tmp = ntohl(ServerID);
389 
390 	    *e++ = 54;	/* ServerID */
391 	    *e++ = 4;
392 	    *e++ = tmp >> 24;
393 	    *e++ = tmp >> 16;
394 	    *e++ = tmp >> 8;
395 	    *e++ = tmp & 0xff;
396     }
397 
398     if ( RequestedIP ) {
399     	    int tmp = ntohl(RequestedIP);
400 
401 	    *e++ = 50;	/* Requested IP */
402 	    *e++ = 4;
403 	    *e++ = tmp >> 24;
404 	    *e++ = tmp >> 16;
405 	    *e++ = tmp >> 8;
406 	    *e++ = tmp & 0xff;
407     }
408 
409 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
410     if ((x = dhcp_vendorex_prep (e)))
411     	return x - start ;
412 #endif
413 
414     *e++ = 55;		/* Parameter Request List */
415     cnt  = e++;		/* Pointer to count of requested items */
416     *cnt = 0;
417 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
418     *e++ = 1;		/* Subnet Mask */
419     *cnt += 1;
420 #endif
421 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
422     *e++ = 3;		/* Router Option */
423     *cnt += 1;
424 #endif
425 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
426     *e++ = 6;		/* DNS Server(s) */
427     *cnt += 1;
428 #endif
429 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
430     *e++ = 12;		/* Hostname */
431     *cnt += 1;
432 #endif
433 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
434     *e++ = 13;		/* Boot File Size */
435     *cnt += 1;
436 #endif
437 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
438     *e++ = 17;		/* Boot path */
439     *cnt += 1;
440 #endif
441 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
442     *e++ = 40;		/* NIS Domain name request */
443     *cnt += 1;
444 #endif
445     *e++ = 255;		/* End of the list */
446 
447     /* Pad to minimal length */
448 #ifdef	CONFIG_DHCP_MIN_EXT_LEN
449     while ((e - start) <= CONFIG_DHCP_MIN_EXT_LEN)
450 	*e++ = 0;
451 #endif
452 
453     return e - start ;
454 }
455 
456 #else	/* CFG_CMD_DHCP */
457 /*
458  *	Warning: no field size check - change CONFIG_BOOTP_MASK at your own risk!
459  */
460 static int BootpExtended (u8 *e)
461 {
462     u8 *start = e ;
463 
464     *e++ =  99;		/* RFC1048 Magic Cookie */
465     *e++ = 130;
466     *e++ =  83;
467     *e++ =  99;
468 
469 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
470     *e++ = 53;		/* DHCP Message Type */
471     *e++ = 1;
472     *e++ = DHCP_DISCOVER;
473 
474     *e++ = 57;		/* Maximum DHCP Message Size */
475     *e++ = 2;
476     *e++ = (576-312+OPT_SIZE) >> 16;
477     *e++ = (576-312+OPT_SIZE) & 0xff;
478 #endif	/* CFG_CMD_DHCP */
479 
480 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_SUBNETMASK)
481     *e++ =  1;		/* Subnet mask request */
482     *e++ =  4;
483      e  +=  4;
484 #endif
485 
486 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_GATEWAY)
487     *e++ =  3;		/* Default gateway request */
488     *e++ =  4;
489      e  +=  4;
490 #endif
491 
492 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_DNS)
493     *e++ =  6;		/* Domain Name Server */
494     *e++ =  4;
495      e  +=  4;
496 #endif
497 
498 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_HOSTNAME)
499     *e++ = 12;		/* Host name request */
500     *e++ = 32;
501      e  += 32;
502 #endif
503 
504 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTFILESIZE)
505     *e++ = 13;		/* Boot file size */
506     *e++ =  2;
507      e  +=  2;
508 #endif
509 
510 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_BOOTPATH)
511     *e++ = 17;		/* Boot path */
512     *e++ = 32;
513      e  += 32;
514 #endif
515 
516 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_NISDOMAIN)
517     *e++ = 40;		/* NIS Domain name request */
518     *e++ = 32;
519      e  += 32;
520 #endif
521 
522     *e++ = 255;		/* End of the list */
523 
524     return e - start ;
525 }
526 #endif	/* CFG_CMD_DHCP */
527 
528 void
529 BootpRequest (void)
530 {
531 	volatile uchar *pkt, *iphdr;
532 	Bootp_t *bp;
533 	int ext_len, pktlen, iplen;
534 
535 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
536 	dhcp_state = INIT;
537 #endif
538 
539 #ifdef CONFIG_BOOTP_RANDOM_DELAY		/* Random BOOTP delay */
540 	unsigned char bi_enetaddr[6];
541 	int   reg;
542 	char  *e,*s;
543 	uchar tmp[64];
544 	ulong tst1, tst2, sum, m_mask, m_value = 0;
545 
546 	if (BootpTry ==0) {
547 		/* get our mac */
548 		reg = getenv_r ("ethaddr", tmp, sizeof(tmp));
549 		s = (reg > 0) ? tmp : NULL;
550 
551 		for (reg=0; reg<6; ++reg) {
552 			bi_enetaddr[reg] = s ? simple_strtoul(s, &e, 16) : 0;
553 			if (s) {
554 				s = (*e) ? e+1 : e;
555 			}
556 		}
557 #ifdef DEBUG
558 		printf("BootpRequest => Our Mac: ");
559 		for (reg=0; reg<6; reg++) {
560 			printf ("%x%c",
561 				bi_enetaddr[reg],
562 				reg==5 ? '\n' : ':');
563 		}
564 #endif /* DEBUG */
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 	NetSetEther(pkt, NetBcastAddr, PROT_IP);
618 	pkt += ETHER_HDR_SIZE;
619 
620 	/*
621 	 * Next line results in incorrect packet size being transmitted, resulting
622 	 * in errors in some DHCP servers, reporting missing bytes.  Size must be
623 	 * set in packet header after extension length has been determined.
624 	 * C. Hallinan, DS4.COM, Inc.
625 	 */
626 	/* NetSetIP(pkt, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, sizeof (Bootp_t)); */
627 	iphdr = pkt;	/* We need this later for NetSetIP() */
628 	pkt += IP_HDR_SIZE;
629 
630 	bp = (Bootp_t *)pkt;
631 	bp->bp_op = OP_BOOTREQUEST;
632 	bp->bp_htype = HWT_ETHER;
633 	bp->bp_hlen = HWL_ETHER;
634 	bp->bp_hops = 0;
635 	bp->bp_secs = htons(get_timer(0) / CFG_HZ);
636 	NetWriteIP(&bp->bp_ciaddr, 0);
637 	NetWriteIP(&bp->bp_yiaddr, 0);
638 	NetWriteIP(&bp->bp_siaddr, 0);
639 	NetWriteIP(&bp->bp_giaddr, 0);
640 	memcpy (bp->bp_chaddr, NetOurEther, 6);
641 	copy_filename (bp->bp_file, BootFile, sizeof(bp->bp_file));
642 
643 	/* Request additional information from the BOOTP/DHCP server */
644 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
645 	ext_len = DhcpExtended(bp->bp_vend, DHCP_DISCOVER, 0, 0);
646 #else
647 	ext_len = BootpExtended(bp->bp_vend);
648 #endif	/* CFG_CMD_DHCP */
649 
650 	/*
651 	 *	Bootp ID is the lower 4 bytes of our ethernet address
652 	 *	plus the current time in HZ.
653 	 */
654 	BootpID = ((ulong)NetOurEther[2] << 24)
655 		| ((ulong)NetOurEther[3] << 16)
656 		| ((ulong)NetOurEther[4] << 8)
657 		| (ulong)NetOurEther[5];
658 	BootpID += get_timer(0);
659 	BootpID  = htonl(BootpID);
660 	NetCopyLong(&bp->bp_id, &BootpID);
661 
662 	/*
663 	 * Calculate proper packet lengths taking into account the
664 	 * variable size of the options field
665 	 */
666 	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + ext_len;
667 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + ext_len;
668 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
669 	NetSetTimeout(SELECT_TIMEOUT * CFG_HZ, BootpTimeout);
670 
671 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
672 	dhcp_state = SELECTING;
673 	NetSetHandler(DhcpHandler);
674 #else
675 	NetSetHandler(BootpHandler);
676 #endif	/* CFG_CMD_DHCP */
677 	NetSendPacket(NetTxPacket, pktlen);
678 }
679 
680 #if (CONFIG_COMMANDS & CFG_CMD_DHCP)
681 static void DhcpOptionsProcess(uchar *popt)
682 {
683 	uchar *end = popt + BOOTP_HDR_SIZE;
684 	int oplen, size;
685 
686 	while ( popt < end && *popt != 0xff ) {
687 		oplen = *(popt + 1);
688 		switch(*popt) {
689 			case  1:
690 				NetCopyIP(&NetOurSubnetMask, (popt+2));
691 				break;
692 			case  3:
693 				NetCopyIP(&NetOurGatewayIP, (popt+2));
694 				break;
695 			case  6:
696 				NetCopyIP(&NetOurDNSIP, (popt+2));
697 				break;
698 			case 12:
699 				size = truncate_sz ("Host Name",
700 						    sizeof(NetOurHostName),
701 						    oplen);
702 				memcpy(&NetOurHostName, popt+2, size);
703 				NetOurHostName[size] = 0 ;
704 				break;
705 			case 15:		/* Ignore Domain Name Option */
706 				break;
707 			case 17:
708 				size = truncate_sz ("Root Path",
709 						    sizeof(NetOurRootPath),
710 						    oplen);
711 				memcpy(&NetOurRootPath, popt+2, size);
712 				NetOurRootPath[size] = 0 ;
713 				break;
714 			case 51:
715 				dhcp_leasetime = *(unsigned int *)(popt + 2);
716 				break;
717 			case 53:		/* Ignore Message Type Option */
718 				break;
719 			case 54:
720 				NetCopyIP(&NetDHCPServerIP, (popt+2));
721 				break;
722 			case 58:		/* Ignore Renewal Time Option */
723 				break;
724 			case 59:		/* Ignore Rebinding Time Option */
725 				break;
726 			default:
727 #if (CONFIG_BOOTP_MASK & CONFIG_BOOTP_VENDOREX)
728 			    if (dhcp_vendorex_proc(popt))
729         			break;
730 #endif
731 				printf("*** Unhandled DHCP Option in OFFER/ACK: %d\n",
732 					*popt);
733 				break;
734 		}
735 		popt += oplen + 2;	/* Process next option */
736 	}
737 }
738 
739 static int DhcpMessageType(unsigned char *popt)
740 {
741 	if (NetReadLong((ulong*)popt) != htonl(BOOTP_VENDOR_MAGIC))
742 		return -1;
743 
744 	popt += 4;
745 	while ( *popt != 0xff ) {
746 		if ( *popt == 53 )	/* DHCP Message Type */
747 			return *(popt + 2);
748 		popt += *(popt + 1) + 2;	/* Scan through all options */
749 	}
750 	return -1;
751 }
752 
753 static void DhcpSendRequestPkt(Bootp_t *bp_offer)
754 {
755 	volatile uchar *pkt, *iphdr;
756 	Bootp_t *bp;
757 	int pktlen, iplen, extlen;
758 	IPaddr_t OfferedIP;
759 
760 	debug ("DhcpSendRequestPkt: Sending DHCPREQUEST\n");
761 	pkt = NetTxPacket;
762 	memset ((void*)pkt, 0, PKTSIZE);
763 
764 	NetSetEther(pkt, NetBcastAddr, PROT_IP);
765 	pkt += ETHER_HDR_SIZE;
766 
767 	iphdr = pkt;		/* We'll need this later to set proper pkt size */
768 	pkt += IP_HDR_SIZE;
769 
770 	bp = (Bootp_t *)pkt;
771 	bp->bp_op = OP_BOOTREQUEST;
772 	bp->bp_htype = HWT_ETHER;
773 	bp->bp_hlen = HWL_ETHER;
774 	bp->bp_hops = 0;
775 	bp->bp_secs = htons(get_timer(0) / CFG_HZ);
776 	NetCopyIP(&bp->bp_ciaddr, &bp_offer->bp_ciaddr); /* both in network byte order */
777 	NetCopyIP(&bp->bp_yiaddr, &bp_offer->bp_yiaddr);
778 	NetCopyIP(&bp->bp_siaddr, &bp_offer->bp_siaddr);
779 	NetCopyIP(&bp->bp_giaddr, &bp_offer->bp_giaddr);
780 	memcpy (bp->bp_chaddr, NetOurEther, 6);
781 
782 	/*
783 	 * ID is the id of the OFFER packet
784 	 */
785 
786 	NetCopyLong(&bp->bp_id, &bp_offer->bp_id);
787 
788 	/*
789 	 * Copy options from OFFER packet if present
790 	 */
791 	NetCopyIP(&OfferedIP, &bp->bp_yiaddr);
792 	extlen = DhcpExtended(bp->bp_vend, DHCP_REQUEST, NetDHCPServerIP, OfferedIP);
793 
794 	pktlen = BOOTP_SIZE - sizeof(bp->bp_vend) + extlen;
795 	iplen = BOOTP_HDR_SIZE - sizeof(bp->bp_vend) + extlen;
796 	NetSetIP(iphdr, 0xFFFFFFFFL, PORT_BOOTPS, PORT_BOOTPC, iplen);
797 
798 	debug ("Transmitting DHCPREQUEST packet: len = %d\n", pktlen);
799 	NetSendPacket(NetTxPacket, pktlen);
800 }
801 
802 /*
803  *	Handle DHCP received packets.
804  */
805 static void
806 DhcpHandler(uchar * pkt, unsigned dest, unsigned src, unsigned len)
807 {
808 	Bootp_t *bp = (Bootp_t *)pkt;
809 
810 	debug ("DHCPHandler: got packet: (src=%d, dst=%d, len=%d) state: %d\n",
811 		src, dest, len, dhcp_state);
812 
813 	if (BootpCheckPkt(pkt, dest, src, len))	/* Filter out pkts we don't want */
814 		return;
815 
816 	debug ("DHCPHandler: got DHCP packet: (src=%d, dst=%d, len=%d) state: %d\n",
817 		src, dest, len, dhcp_state);
818 
819 	switch (dhcp_state) {
820 	case SELECTING:
821 		/*
822 		 * Wait an appropriate time for any potential DHCPOFFER packets
823 		 * to arrive.  Then select one, and generate DHCPREQUEST response.
824 		 * If filename is in format we recognize, assume it is a valid
825 		 * OFFER from a server we want.
826 		 */
827 		debug ("DHCP: state=SELECTING bp_file: \"%s\"\n", bp->bp_file);
828 #ifdef CFG_BOOTFILE_PREFIX
829 		if (strncmp(bp->bp_file,
830 			    CFG_BOOTFILE_PREFIX,
831 			    strlen(CFG_BOOTFILE_PREFIX)) == 0 ) {
832 #endif	/* CFG_BOOTFILE_PREFIX */
833 
834 			debug ("TRANSITIONING TO REQUESTING STATE\n");
835 			dhcp_state = REQUESTING;
836 
837 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
838 				DhcpOptionsProcess(&bp->bp_vend[4]);
839 
840 			BootpCopyNetParams(bp);	/* Store net params from reply */
841 
842 			NetSetTimeout(TIMEOUT * CFG_HZ, BootpTimeout);
843 			DhcpSendRequestPkt(bp);
844 #ifdef CFG_BOOTFILE_PREFIX
845 		}
846 #endif	/* CFG_BOOTFILE_PREFIX */
847 
848 		return;
849 		break;
850 	case REQUESTING:
851 		debug ("DHCP State: REQUESTING\n");
852 
853 		if ( DhcpMessageType(bp->bp_vend) == DHCP_ACK ) {
854 			char *s;
855 
856 			if (NetReadLong((ulong*)&bp->bp_vend[0]) == htonl(BOOTP_VENDOR_MAGIC))
857 				DhcpOptionsProcess(&bp->bp_vend[4]);
858 			BootpCopyNetParams(bp);	/* Store net params from reply */
859 			dhcp_state = BOUND;
860 			printf("DHCP client bound to address ");
861 			print_IPaddr(NetOurIP);
862 			printf("\n");
863 
864 			/* Obey the 'autoload' setting */
865 			if (((s = getenv("autoload")) != NULL) && (*s == 'n')) {
866 				NetState = NETLOOP_SUCCESS;
867 				return;
868 			}
869 			/* Send ARP request to get TFTP server ethernet address.
870 			 * This automagically starts TFTP, too.
871 			 */
872 			ArpRequest();
873 			return;
874 		}
875 		break;
876 	default:
877 		printf("DHCP: INVALID STATE\n");
878 		break;
879 	}
880 
881 }
882 
883 void DhcpRequest(void)
884 {
885 	BootpRequest();
886 }
887 #endif	/* CFG_CMD_DHCP */
888 
889 #endif /* CFG_CMD_NET */
890