xref: /rk3399_rockchip-uboot/net/tftp.c (revision 2f09413fd9ca949715d77f31b5a695bbb142e8c6)
1 /*
2  * Copyright 1994, 1995, 2000 Neil Russell.
3  * (See License)
4  * Copyright 2000, 2001 DENX Software Engineering, Wolfgang Denk, wd@denx.de
5  */
6 
7 #include <common.h>
8 #include <command.h>
9 #include <net.h>
10 #include "tftp.h"
11 #include "bootp.h"
12 
13 /* Well known TFTP port # */
14 #define WELL_KNOWN_PORT	69
15 /* Millisecs to timeout for lost pkt */
16 #define TIMEOUT		5000UL
17 #ifndef	CONFIG_NET_RETRY_COUNT
18 /* # of timeouts before giving up */
19 # define TIMEOUT_COUNT	10
20 #else
21 # define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT * 2)
22 #endif
23 /* Number of "loading" hashes per line (for checking the image size) */
24 #define HASHES_PER_LINE	65
25 
26 /*
27  *	TFTP operations.
28  */
29 #define TFTP_RRQ	1
30 #define TFTP_WRQ	2
31 #define TFTP_DATA	3
32 #define TFTP_ACK	4
33 #define TFTP_ERROR	5
34 #define TFTP_OACK	6
35 
36 static ulong TftpTimeoutMSecs = TIMEOUT;
37 static int TftpTimeoutCountMax = TIMEOUT_COUNT;
38 
39 /*
40  * These globals govern the timeout behavior when attempting a connection to a
41  * TFTP server. TftpRRQTimeoutMSecs specifies the number of milliseconds to
42  * wait for the server to respond to initial connection. Second global,
43  * TftpRRQTimeoutCountMax, gives the number of such connection retries.
44  * TftpRRQTimeoutCountMax must be non-negative and TftpRRQTimeoutMSecs must be
45  * positive. The globals are meant to be set (and restored) by code needing
46  * non-standard timeout behavior when initiating a TFTP transfer.
47  */
48 ulong TftpRRQTimeoutMSecs = TIMEOUT;
49 int TftpRRQTimeoutCountMax = TIMEOUT_COUNT;
50 
51 enum {
52 	TFTP_ERR_UNDEFINED           = 0,
53 	TFTP_ERR_FILE_NOT_FOUND      = 1,
54 	TFTP_ERR_ACCESS_DENIED       = 2,
55 	TFTP_ERR_DISK_FULL           = 3,
56 	TFTP_ERR_UNEXPECTED_OPCODE   = 4,
57 	TFTP_ERR_UNKNOWN_TRANSFER_ID  = 5,
58 	TFTP_ERR_FILE_ALREADY_EXISTS = 6,
59 };
60 
61 static IPaddr_t TftpServerIP;
62 /* The UDP port at their end */
63 static int	TftpServerPort;
64 /* The UDP port at our end */
65 static int	TftpOurPort;
66 static int	TftpTimeoutCount;
67 /* packet sequence number */
68 static ulong	TftpBlock;
69 /* last packet sequence number received */
70 static ulong	TftpLastBlock;
71 /* count of sequence number wraparounds */
72 static ulong	TftpBlockWrap;
73 /* memory offset due to wrapping */
74 static ulong	TftpBlockWrapOffset;
75 static int	TftpState;
76 #ifdef CONFIG_TFTP_TSIZE
77 /* The file size reported by the server */
78 static int	TftpTsize;
79 /* The number of hashes we printed */
80 static short	TftpNumchars;
81 #endif
82 
83 #define STATE_RRQ	1
84 #define STATE_DATA	2
85 #define STATE_TOO_LARGE	3
86 #define STATE_BAD_MAGIC	4
87 #define STATE_OACK	5
88 
89 /* default TFTP block size */
90 #define TFTP_BLOCK_SIZE		512
91 /* sequence number is 16 bit */
92 #define TFTP_SEQUENCE_SIZE	((ulong)(1<<16))
93 
94 #define DEFAULT_NAME_LEN	(8 + 4 + 1)
95 static char default_filename[DEFAULT_NAME_LEN];
96 
97 #ifndef CONFIG_TFTP_FILE_NAME_MAX_LEN
98 #define MAX_LEN 128
99 #else
100 #define MAX_LEN CONFIG_TFTP_FILE_NAME_MAX_LEN
101 #endif
102 
103 static char tftp_filename[MAX_LEN];
104 
105 #ifdef CONFIG_SYS_DIRECT_FLASH_TFTP
106 extern flash_info_t flash_info[];
107 #endif
108 
109 /* 512 is poor choice for ethernet, MTU is typically 1500.
110  * Minus eth.hdrs thats 1468.  Can get 2x better throughput with
111  * almost-MTU block sizes.  At least try... fall back to 512 if need be.
112  * (but those using CONFIG_IP_DEFRAG may want to set a larger block in cfg file)
113  */
114 #ifdef CONFIG_TFTP_BLOCKSIZE
115 #define TFTP_MTU_BLOCKSIZE CONFIG_TFTP_BLOCKSIZE
116 #else
117 #define TFTP_MTU_BLOCKSIZE 1468
118 #endif
119 
120 static unsigned short TftpBlkSize=TFTP_BLOCK_SIZE;
121 static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;
122 
123 #ifdef CONFIG_MCAST_TFTP
124 #include <malloc.h>
125 #define MTFTP_BITMAPSIZE	0x1000
126 static unsigned *Bitmap;
127 static int PrevBitmapHole,Mapsize=MTFTP_BITMAPSIZE;
128 static uchar ProhibitMcast=0, MasterClient=0;
129 static uchar Multicast=0;
130 extern IPaddr_t Mcast_addr;
131 static int Mcast_port;
132 static ulong TftpEndingBlock; /* can get 'last' block before done..*/
133 
134 static void parse_multicast_oack(char *pkt,int len);
135 
136 static void
137 mcast_cleanup(void)
138 {
139 	if (Mcast_addr) eth_mcast_join(Mcast_addr, 0);
140 	if (Bitmap) free(Bitmap);
141 	Bitmap=NULL;
142 	Mcast_addr = Multicast = Mcast_port = 0;
143 	TftpEndingBlock = -1;
144 }
145 
146 #endif	/* CONFIG_MCAST_TFTP */
147 
148 static __inline__ void
149 store_block (unsigned block, uchar * src, unsigned len)
150 {
151 	ulong offset = block * TftpBlkSize + TftpBlockWrapOffset;
152 	ulong newsize = offset + len;
153 #ifdef CONFIG_SYS_DIRECT_FLASH_TFTP
154 	int i, rc = 0;
155 
156 	for (i=0; i<CONFIG_SYS_MAX_FLASH_BANKS; i++) {
157 		/* start address in flash? */
158 		if (flash_info[i].flash_id == FLASH_UNKNOWN)
159 			continue;
160 		if (load_addr + offset >= flash_info[i].start[0]) {
161 			rc = 1;
162 			break;
163 		}
164 	}
165 
166 	if (rc) { /* Flash is destination for this packet */
167 		rc = flash_write ((char *)src, (ulong)(load_addr+offset), len);
168 		if (rc) {
169 			flash_perror (rc);
170 			NetState = NETLOOP_FAIL;
171 			return;
172 		}
173 	}
174 	else
175 #endif /* CONFIG_SYS_DIRECT_FLASH_TFTP */
176 	{
177 		(void)memcpy((void *)(load_addr + offset), src, len);
178 	}
179 #ifdef CONFIG_MCAST_TFTP
180 	if (Multicast)
181 		ext2_set_bit(block, Bitmap);
182 #endif
183 
184 	if (NetBootFileXferSize < newsize)
185 		NetBootFileXferSize = newsize;
186 }
187 
188 static void TftpSend (void);
189 static void TftpTimeout (void);
190 
191 /**********************************************************************/
192 
193 static void
194 TftpSend (void)
195 {
196 	volatile uchar *	pkt;
197 	volatile uchar *	xp;
198 	int			len = 0;
199 	volatile ushort *s;
200 
201 #ifdef CONFIG_MCAST_TFTP
202 	/* Multicast TFTP.. non-MasterClients do not ACK data. */
203 	if (Multicast
204 	 && (TftpState == STATE_DATA)
205 	 && (MasterClient == 0))
206 		return;
207 #endif
208 	/*
209 	 *	We will always be sending some sort of packet, so
210 	 *	cobble together the packet headers now.
211 	 */
212 	pkt = NetTxPacket + NetEthHdrSize() + IP_HDR_SIZE;
213 
214 	switch (TftpState) {
215 
216 	case STATE_RRQ:
217 		xp = pkt;
218 		s = (ushort *)pkt;
219 		*s++ = htons(TFTP_RRQ);
220 		pkt = (uchar *)s;
221 		strcpy ((char *)pkt, tftp_filename);
222 		pkt += strlen(tftp_filename) + 1;
223 		strcpy ((char *)pkt, "octet");
224 		pkt += 5 /*strlen("octet")*/ + 1;
225 		strcpy ((char *)pkt, "timeout");
226 		pkt += 7 /*strlen("timeout")*/ + 1;
227 		sprintf((char *)pkt, "%lu", TftpTimeoutMSecs / 1000);
228 		debug("send option \"timeout %s\"\n", (char *)pkt);
229 		pkt += strlen((char *)pkt) + 1;
230 #ifdef CONFIG_TFTP_TSIZE
231 		memcpy((char *)pkt, "tsize\0000\0", 8);
232 		pkt += 8;
233 #endif
234 		/* try for more effic. blk size */
235 		pkt += sprintf((char *)pkt,"blksize%c%d%c",
236 				0,TftpBlkSizeOption,0);
237 #ifdef CONFIG_MCAST_TFTP
238 		/* Check all preconditions before even trying the option */
239 		if (!ProhibitMcast
240 		 && (Bitmap=malloc(Mapsize))
241 		 && eth_get_dev()->mcast) {
242 			free(Bitmap);
243 			Bitmap=NULL;
244 			pkt += sprintf((char *)pkt,"multicast%c%c",0,0);
245 		}
246 #endif /* CONFIG_MCAST_TFTP */
247 		len = pkt - xp;
248 		break;
249 
250 	case STATE_OACK:
251 #ifdef CONFIG_MCAST_TFTP
252 		/* My turn!  Start at where I need blocks I missed.*/
253 		if (Multicast)
254 			TftpBlock=ext2_find_next_zero_bit(Bitmap,(Mapsize*8),0);
255 		/*..falling..*/
256 #endif
257 	case STATE_DATA:
258 		xp = pkt;
259 		s = (ushort *)pkt;
260 		*s++ = htons(TFTP_ACK);
261 		*s++ = htons(TftpBlock);
262 		pkt = (uchar *)s;
263 		len = pkt - xp;
264 		break;
265 
266 	case STATE_TOO_LARGE:
267 		xp = pkt;
268 		s = (ushort *)pkt;
269 		*s++ = htons(TFTP_ERROR);
270 		*s++ = htons(3);
271 		pkt = (uchar *)s;
272 		strcpy ((char *)pkt, "File too large");
273 		pkt += 14 /*strlen("File too large")*/ + 1;
274 		len = pkt - xp;
275 		break;
276 
277 	case STATE_BAD_MAGIC:
278 		xp = pkt;
279 		s = (ushort *)pkt;
280 		*s++ = htons(TFTP_ERROR);
281 		*s++ = htons(2);
282 		pkt = (uchar *)s;
283 		strcpy ((char *)pkt, "File has bad magic");
284 		pkt += 18 /*strlen("File has bad magic")*/ + 1;
285 		len = pkt - xp;
286 		break;
287 	}
288 
289 	NetSendUDPPacket(NetServerEther, TftpServerIP, TftpServerPort,
290 			 TftpOurPort, len);
291 }
292 
293 
294 static void
295 TftpHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
296 	    unsigned len)
297 {
298 	ushort proto;
299 	ushort *s;
300 	int i;
301 
302 	if (dest != TftpOurPort) {
303 #ifdef CONFIG_MCAST_TFTP
304 		if (Multicast
305 		 && (!Mcast_port || (dest != Mcast_port)))
306 #endif
307 		return;
308 	}
309 	if (TftpState != STATE_RRQ && src != TftpServerPort) {
310 		return;
311 	}
312 
313 	if (len < 2) {
314 		return;
315 	}
316 	len -= 2;
317 	/* warning: don't use increment (++) in ntohs() macros!! */
318 	s = (ushort *)pkt;
319 	proto = *s++;
320 	pkt = (uchar *)s;
321 	switch (ntohs(proto)) {
322 
323 	case TFTP_RRQ:
324 	case TFTP_WRQ:
325 	case TFTP_ACK:
326 		break;
327 	default:
328 		break;
329 
330 	case TFTP_OACK:
331 		debug("Got OACK: %s %s\n",
332 			pkt,
333 			pkt + strlen((char *)pkt) + 1);
334 		TftpState = STATE_OACK;
335 		TftpServerPort = src;
336 		/*
337 		 * Check for 'blksize' option.
338 		 * Careful: "i" is signed, "len" is unsigned, thus
339 		 * something like "len-8" may give a *huge* number
340 		 */
341 		for (i=0; i+8<len; i++) {
342 			if (strcmp ((char*)pkt+i,"blksize") == 0) {
343 				TftpBlkSize = (unsigned short)
344 					simple_strtoul((char*)pkt+i+8,NULL,10);
345 				debug("Blocksize ack: %s, %d\n",
346 					(char*)pkt+i+8,TftpBlkSize);
347 			}
348 #ifdef CONFIG_TFTP_TSIZE
349 			if (strcmp ((char*)pkt+i,"tsize") == 0) {
350 				TftpTsize = simple_strtoul((char*)pkt+i+6,
351 							   NULL, 10);
352 				debug("size = %s, %d\n",
353 					 (char*)pkt+i+6, TftpTsize);
354 			}
355 #endif
356 		}
357 #ifdef CONFIG_MCAST_TFTP
358 		parse_multicast_oack((char *)pkt,len-1);
359 		if ((Multicast) && (!MasterClient))
360 			TftpState = STATE_DATA;	/* passive.. */
361 		else
362 #endif
363 		TftpSend (); /* Send ACK */
364 		break;
365 	case TFTP_DATA:
366 		if (len < 2)
367 			return;
368 		len -= 2;
369 		TftpBlock = ntohs(*(ushort *)pkt);
370 
371 		/*
372 		 * RFC1350 specifies that the first data packet will
373 		 * have sequence number 1. If we receive a sequence
374 		 * number of 0 this means that there was a wrap
375 		 * around of the (16 bit) counter.
376 		 */
377 		if (TftpBlock == 0) {
378 			TftpBlockWrap++;
379 			TftpBlockWrapOffset +=
380 				TftpBlkSize * TFTP_SEQUENCE_SIZE;
381 			printf ("\n\t %lu MB received\n\t ",
382 				TftpBlockWrapOffset>>20);
383 		}
384 #ifdef CONFIG_TFTP_TSIZE
385 		else if (TftpTsize) {
386 			while (TftpNumchars <
387 			       NetBootFileXferSize * 50 / TftpTsize) {
388 				putc('#');
389 				TftpNumchars++;
390 			}
391 		}
392 #endif
393 		else {
394 			if (((TftpBlock - 1) % 10) == 0) {
395 				putc ('#');
396 			} else if ((TftpBlock % (10 * HASHES_PER_LINE)) == 0) {
397 				puts ("\n\t ");
398 			}
399 		}
400 
401 		if (TftpState == STATE_RRQ)
402 			debug("Server did not acknowledge timeout option!\n");
403 
404 		if (TftpState == STATE_RRQ || TftpState == STATE_OACK) {
405 			/* first block received */
406 			TftpState = STATE_DATA;
407 			TftpServerPort = src;
408 			TftpLastBlock = 0;
409 			TftpBlockWrap = 0;
410 			TftpBlockWrapOffset = 0;
411 
412 #ifdef CONFIG_MCAST_TFTP
413 			if (Multicast) { /* start!=1 common if mcast */
414 				TftpLastBlock = TftpBlock - 1;
415 			} else
416 #endif
417 			if (TftpBlock != 1) {	/* Assertion */
418 				printf ("\nTFTP error: "
419 					"First block is not block 1 (%ld)\n"
420 					"Starting again\n\n",
421 					TftpBlock);
422 				NetStartAgain ();
423 				break;
424 			}
425 		}
426 
427 		if (TftpBlock == TftpLastBlock) {
428 			/*
429 			 *	Same block again; ignore it.
430 			 */
431 			break;
432 		}
433 
434 		TftpLastBlock = TftpBlock;
435 		TftpTimeoutCountMax = TIMEOUT_COUNT;
436 		NetSetTimeout (TftpTimeoutMSecs, TftpTimeout);
437 
438 		store_block (TftpBlock - 1, pkt + 2, len);
439 
440 		/*
441 		 *	Acknoledge the block just received, which will prompt
442 		 *	the server for the next one.
443 		 */
444 #ifdef CONFIG_MCAST_TFTP
445 		/* if I am the MasterClient, actively calculate what my next
446 		 * needed block is; else I'm passive; not ACKING
447 		 */
448 		if (Multicast) {
449 			if (len < TftpBlkSize)  {
450 				TftpEndingBlock = TftpBlock;
451 			} else if (MasterClient) {
452 				TftpBlock = PrevBitmapHole =
453 					ext2_find_next_zero_bit(
454 						Bitmap,
455 						(Mapsize*8),
456 						PrevBitmapHole);
457 				if (TftpBlock > ((Mapsize*8) - 1)) {
458 					printf ("tftpfile too big\n");
459 					/* try to double it and retry */
460 					Mapsize<<=1;
461 					mcast_cleanup();
462 					NetStartAgain ();
463 					return;
464 				}
465 				TftpLastBlock = TftpBlock;
466 			}
467 		}
468 #endif
469 		TftpSend ();
470 
471 #ifdef CONFIG_MCAST_TFTP
472 		if (Multicast) {
473 			if (MasterClient && (TftpBlock >= TftpEndingBlock)) {
474 				puts ("\nMulticast tftp done\n");
475 				mcast_cleanup();
476 				NetState = NETLOOP_SUCCESS;
477 			}
478 		}
479 		else
480 #endif
481 		if (len < TftpBlkSize) {
482 			/*
483 			 *	We received the whole thing.  Try to
484 			 *	run it.
485 			 */
486 #ifdef CONFIG_TFTP_TSIZE
487 			/* Print hash marks for the last packet received */
488 			while (TftpTsize && TftpNumchars < 49) {
489 				putc('#');
490 				TftpNumchars++;
491 			}
492 #endif
493 			puts ("\ndone\n");
494 			NetState = NETLOOP_SUCCESS;
495 		}
496 		break;
497 
498 	case TFTP_ERROR:
499 		printf ("\nTFTP error: '%s' (%d)\n",
500 					pkt + 2, ntohs(*(ushort *)pkt));
501 
502 		switch (ntohs(*(ushort *)pkt)) {
503 		case TFTP_ERR_FILE_NOT_FOUND:
504 		case TFTP_ERR_ACCESS_DENIED:
505 			puts("Not retrying...\n");
506 			eth_halt();
507 			NetState = NETLOOP_FAIL;
508 			break;
509 		case TFTP_ERR_UNDEFINED:
510 		case TFTP_ERR_DISK_FULL:
511 		case TFTP_ERR_UNEXPECTED_OPCODE:
512 		case TFTP_ERR_UNKNOWN_TRANSFER_ID:
513 		case TFTP_ERR_FILE_ALREADY_EXISTS:
514 		default:
515 			puts("Starting again\n\n");
516 #ifdef CONFIG_MCAST_TFTP
517 			mcast_cleanup();
518 #endif
519 			NetStartAgain();
520 			break;
521 		}
522 		break;
523 	}
524 }
525 
526 
527 static void
528 TftpTimeout (void)
529 {
530 	if (++TftpTimeoutCount > TftpTimeoutCountMax) {
531 		puts ("\nRetry count exceeded; starting again\n");
532 #ifdef CONFIG_MCAST_TFTP
533 		mcast_cleanup();
534 #endif
535 		NetStartAgain ();
536 	} else {
537 		puts ("T ");
538 		NetSetTimeout (TftpTimeoutMSecs, TftpTimeout);
539 		TftpSend ();
540 	}
541 }
542 
543 
544 void
545 TftpStart (void)
546 {
547 	char *ep;             /* Environment pointer */
548 
549 	/*
550 	 * Allow the user to choose TFTP blocksize and timeout.
551 	 * TFTP protocol has a minimal timeout of 1 second.
552 	 */
553 	if ((ep = getenv("tftpblocksize")) != NULL)
554 		TftpBlkSizeOption = simple_strtol(ep, NULL, 10);
555 
556 	if ((ep = getenv("tftptimeout")) != NULL)
557 		TftpTimeoutMSecs = simple_strtol(ep, NULL, 10);
558 
559 	if (TftpTimeoutMSecs < 1000) {
560 		printf("TFTP timeout (%ld ms) too low, "
561 			"set minimum = 1000 ms\n",
562 			TftpTimeoutMSecs);
563 		TftpTimeoutMSecs = 1000;
564 	}
565 
566 	debug("TFTP blocksize = %i, timeout = %ld ms\n",
567 		TftpBlkSizeOption, TftpTimeoutMSecs);
568 
569 	TftpServerIP = NetServerIP;
570 	if (BootFile[0] == '\0') {
571 		sprintf(default_filename, "%02lX%02lX%02lX%02lX.img",
572 			NetOurIP & 0xFF,
573 			(NetOurIP >>  8) & 0xFF,
574 			(NetOurIP >> 16) & 0xFF,
575 			(NetOurIP >> 24) & 0xFF	);
576 
577 		strncpy(tftp_filename, default_filename, MAX_LEN);
578 		tftp_filename[MAX_LEN-1] = 0;
579 
580 		printf ("*** Warning: no boot file name; using '%s'\n",
581 			tftp_filename);
582 	} else {
583 		char *p = strchr (BootFile, ':');
584 
585 		if (p == NULL) {
586 			strncpy(tftp_filename, BootFile, MAX_LEN);
587 			tftp_filename[MAX_LEN-1] = 0;
588 		} else {
589 			TftpServerIP = string_to_ip (BootFile);
590 			strncpy(tftp_filename, p + 1, MAX_LEN);
591 			tftp_filename[MAX_LEN-1] = 0;
592 		}
593 	}
594 
595 #if defined(CONFIG_NET_MULTI)
596 	printf ("Using %s device\n", eth_get_name());
597 #endif
598 	printf("TFTP from server %pI4"
599 		"; our IP address is %pI4", &TftpServerIP, &NetOurIP);
600 
601 	/* Check if we need to send across this subnet */
602 	if (NetOurGatewayIP && NetOurSubnetMask) {
603 	    IPaddr_t OurNet	= NetOurIP    & NetOurSubnetMask;
604 	    IPaddr_t ServerNet	= TftpServerIP & NetOurSubnetMask;
605 
606 	    if (OurNet != ServerNet)
607 		printf("; sending through gateway %pI4", &NetOurGatewayIP);
608 	}
609 	putc ('\n');
610 
611 	printf ("Filename '%s'.", tftp_filename);
612 
613 	if (NetBootFileSize) {
614 		printf (" Size is 0x%x Bytes = ", NetBootFileSize<<9);
615 		print_size (NetBootFileSize<<9, "");
616 	}
617 
618 	putc ('\n');
619 
620 	printf ("Load address: 0x%lx\n", load_addr);
621 
622 	puts ("Loading: *\b");
623 
624 	TftpTimeoutCountMax = TftpRRQTimeoutCountMax;
625 
626 	NetSetTimeout (TftpTimeoutMSecs, TftpTimeout);
627 	NetSetHandler (TftpHandler);
628 
629 	TftpServerPort = WELL_KNOWN_PORT;
630 	TftpTimeoutCount = 0;
631 	TftpState = STATE_RRQ;
632 	/* Use a pseudo-random port unless a specific port is set */
633 	TftpOurPort = 1024 + (get_timer(0) % 3072);
634 
635 #ifdef CONFIG_TFTP_PORT
636 	if ((ep = getenv("tftpdstp")) != NULL) {
637 		TftpServerPort = simple_strtol(ep, NULL, 10);
638 	}
639 	if ((ep = getenv("tftpsrcp")) != NULL) {
640 		TftpOurPort= simple_strtol(ep, NULL, 10);
641 	}
642 #endif
643 	TftpBlock = 0;
644 
645 	/* zero out server ether in case the server ip has changed */
646 	memset(NetServerEther, 0, 6);
647 	/* Revert TftpBlkSize to dflt */
648 	TftpBlkSize = TFTP_BLOCK_SIZE;
649 #ifdef CONFIG_MCAST_TFTP
650 	mcast_cleanup();
651 #endif
652 #ifdef CONFIG_TFTP_TSIZE
653 	TftpTsize = 0;
654 	TftpNumchars = 0;
655 #endif
656 
657 	TftpSend ();
658 }
659 
660 #ifdef CONFIG_MCAST_TFTP
661 /* Credits: atftp project.
662  */
663 
664 /* pick up BcastAddr, Port, and whether I am [now] the master-client. *
665  * Frame:
666  *    +-------+-----------+---+-------~~-------+---+
667  *    |  opc  | multicast | 0 | addr, port, mc | 0 |
668  *    +-------+-----------+---+-------~~-------+---+
669  * The multicast addr/port becomes what I listen to, and if 'mc' is '1' then
670  * I am the new master-client so must send ACKs to DataBlocks.  If I am not
671  * master-client, I'm a passive client, gathering what DataBlocks I may and
672  * making note of which ones I got in my bitmask.
673  * In theory, I never go from master->passive..
674  * .. this comes in with pkt already pointing just past opc
675  */
676 static void parse_multicast_oack(char *pkt, int len)
677 {
678  int i;
679  IPaddr_t addr;
680  char *mc_adr, *port,  *mc;
681 
682 	mc_adr=port=mc=NULL;
683 	/* march along looking for 'multicast\0', which has to start at least
684 	 * 14 bytes back from the end.
685 	 */
686 	for (i=0;i<len-14;i++)
687 		if (strcmp (pkt+i,"multicast") == 0)
688 			break;
689 	if (i >= (len-14)) /* non-Multicast OACK, ign. */
690 		return;
691 
692 	i+=10; /* strlen multicast */
693 	mc_adr = pkt+i;
694 	for (;i<len;i++) {
695 		if (*(pkt+i) == ',') {
696 			*(pkt+i) = '\0';
697 			if (port) {
698 				mc = pkt+i+1;
699 				break;
700 			} else {
701 				port = pkt+i+1;
702 			}
703 		}
704 	}
705 	if (!port || !mc_adr || !mc ) return;
706 	if (Multicast && MasterClient) {
707 		printf ("I got a OACK as master Client, WRONG!\n");
708 		return;
709 	}
710 	/* ..I now accept packets destined for this MCAST addr, port */
711 	if (!Multicast) {
712 		if (Bitmap) {
713 			printf ("Internal failure! no mcast.\n");
714 			free(Bitmap);
715 			Bitmap=NULL;
716 			ProhibitMcast=1;
717 			return ;
718 		}
719 		/* I malloc instead of pre-declare; so that if the file ends
720 		 * up being too big for this bitmap I can retry
721 		 */
722 		if (!(Bitmap = malloc (Mapsize))) {
723 			printf ("No Bitmap, no multicast. Sorry.\n");
724 			ProhibitMcast=1;
725 			return;
726 		}
727 		memset (Bitmap,0,Mapsize);
728 		PrevBitmapHole = 0;
729 		Multicast = 1;
730 	}
731 	addr = string_to_ip(mc_adr);
732 	if (Mcast_addr != addr) {
733 		if (Mcast_addr)
734 			eth_mcast_join(Mcast_addr, 0);
735 		if (eth_mcast_join(Mcast_addr=addr, 1)) {
736 			printf ("Fail to set mcast, revert to TFTP\n");
737 			ProhibitMcast=1;
738 			mcast_cleanup();
739 			NetStartAgain();
740 		}
741 	}
742 	MasterClient = (unsigned char)simple_strtoul((char *)mc,NULL,10);
743 	Mcast_port = (unsigned short)simple_strtoul(port,NULL,10);
744 	printf ("Multicast: %s:%d [%d]\n", mc_adr, Mcast_port, MasterClient);
745 	return;
746 }
747 
748 #endif /* Multicast TFTP */
749