xref: /rk3399_rockchip-uboot/net/net.c (revision c68cca35b33c3a7c9fbcfc08de7e91dbdc8cf51f)
1 /*
2  *	Copied from Linux Monitor (LiMon) - Networking.
3  *
4  *	Copyright 1994 - 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 /*
12  * General Desription:
13  *
14  * The user interface supports commands for BOOTP, RARP, and TFTP.
15  * Also, we support ARP internally. Depending on available data,
16  * these interact as follows:
17  *
18  * BOOTP:
19  *
20  *	Prerequisites:	- own ethernet address
21  *	We want:	- own IP address
22  *			- TFTP server IP address
23  *			- name of bootfile
24  *	Next step:	ARP
25  *
26  * RARP:
27  *
28  *	Prerequisites:	- own ethernet address
29  *	We want:	- own IP address
30  *			- TFTP server IP address
31  *	Next step:	ARP
32  *
33  * ARP:
34  *
35  *	Prerequisites:	- own ethernet address
36  *			- own IP address
37  *			- TFTP server IP address
38  *	We want:	- TFTP server ethernet address
39  *	Next step:	TFTP
40  *
41  * DHCP:
42  *
43  *     Prerequisites:	- own ethernet address
44  *     We want:		- IP, Netmask, ServerIP, Gateway IP
45  *			- bootfilename, lease time
46  *     Next step:	- TFTP
47  *
48  * TFTP:
49  *
50  *	Prerequisites:	- own ethernet address
51  *			- own IP address
52  *			- TFTP server IP address
53  *			- TFTP server ethernet address
54  *			- name of bootfile (if unknown, we use a default name
55  *			  derived from our own IP address)
56  *	We want:	- load the boot file
57  *	Next step:	none
58  *
59  * NFS:
60  *
61  *	Prerequisites:	- own ethernet address
62  *			- own IP address
63  *			- name of bootfile (if unknown, we use a default name
64  *			  derived from our own IP address)
65  *	We want:	- load the boot file
66  *	Next step:	none
67  *
68  * SNTP:
69  *
70  *	Prerequisites:	- own ethernet address
71  *			- own IP address
72  *	We want:	- network time
73  *	Next step:	none
74  */
75 
76 
77 #include <common.h>
78 #include <watchdog.h>
79 #include <command.h>
80 #include <linux/compiler.h>
81 #include <net.h>
82 #include "arp.h"
83 #include "bootp.h"
84 #include "tftp.h"
85 #include "rarp.h"
86 #include "nfs.h"
87 #ifdef CONFIG_STATUS_LED
88 #include <status_led.h>
89 #include <miiphy.h>
90 #endif
91 #if defined(CONFIG_CMD_SNTP)
92 #include "sntp.h"
93 #endif
94 #include "cdp.h"
95 #if defined(CONFIG_CMD_DNS)
96 #include "dns.h"
97 #endif
98 #include "ping.h"
99 
100 DECLARE_GLOBAL_DATA_PTR;
101 
102 /** BOOTP EXTENTIONS **/
103 
104 /* Our subnet mask (0=unknown) */
105 IPaddr_t	NetOurSubnetMask;
106 /* Our gateways IP address */
107 IPaddr_t	NetOurGatewayIP;
108 /* Our DNS IP address */
109 IPaddr_t	NetOurDNSIP;
110 #if defined(CONFIG_BOOTP_DNS2)
111 /* Our 2nd DNS IP address */
112 IPaddr_t	NetOurDNS2IP;
113 #endif
114 /* Our NIS domain */
115 char		NetOurNISDomain[32] = {0,};
116 /* Our hostname */
117 char		NetOurHostName[32] = {0,};
118 /* Our bootpath */
119 char		NetOurRootPath[64] = {0,};
120 /* Our bootfile size in blocks */
121 ushort		NetBootFileSize;
122 
123 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
124 IPaddr_t Mcast_addr;
125 #endif
126 
127 /** END OF BOOTP EXTENTIONS **/
128 
129 /* The actual transferred size of the bootfile (in bytes) */
130 ulong		NetBootFileXferSize;
131 /* Our ethernet address */
132 uchar		NetOurEther[6];
133 /* Boot server enet address */
134 uchar		NetServerEther[6];
135 /* Our IP addr (0 = unknown) */
136 IPaddr_t	NetOurIP;
137 /* Server IP addr (0 = unknown) */
138 IPaddr_t	NetServerIP;
139 /* Current receive packet */
140 uchar *NetRxPacket;
141 /* Current rx packet length */
142 int		NetRxPacketLen;
143 /* IP packet ID */
144 unsigned	NetIPID;
145 /* Ethernet bcast address */
146 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
147 uchar		NetEtherNullAddr[6];
148 #ifdef CONFIG_API
149 void		(*push_packet)(void *, int len) = 0;
150 #endif
151 /* Network loop state */
152 int		NetState;
153 /* Tried all network devices */
154 int		NetRestartWrap;
155 /* Network loop restarted */
156 static int	NetRestarted;
157 /* At least one device configured */
158 static int	NetDevExists;
159 
160 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
161 /* default is without VLAN */
162 ushort		NetOurVLAN = 0xFFFF;
163 /* ditto */
164 ushort		NetOurNativeVLAN = 0xFFFF;
165 
166 /* Boot File name */
167 char		BootFile[128];
168 
169 #if defined(CONFIG_CMD_SNTP)
170 /* NTP server IP address */
171 IPaddr_t	NetNtpServerIP;
172 /* offset time from UTC */
173 int		NetTimeOffset;
174 #endif
175 
176 uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
177 
178 /* Receive packet */
179 uchar *NetRxPackets[PKTBUFSRX];
180 
181 /* Current RX packet handler */
182 static rxhand_f *packetHandler;
183 #ifdef CONFIG_CMD_TFTPPUT
184 static rxhand_icmp_f *packet_icmp_handler;	/* Current ICMP rx handler */
185 #endif
186 /* Current timeout handler */
187 static thand_f *timeHandler;
188 /* Time base value */
189 static ulong	timeStart;
190 /* Current timeout value */
191 static ulong	timeDelta;
192 /* THE transmit packet */
193 uchar *NetTxPacket;
194 
195 static int net_check_prereq(enum proto_t protocol);
196 
197 static int NetTryCount;
198 
199 /**********************************************************************/
200 
201 /*
202  * Check if autoload is enabled. If so, use either NFS or TFTP to download
203  * the boot file.
204  */
205 void net_auto_load(void)
206 {
207 	const char *s = getenv("autoload");
208 
209 	if (s != NULL) {
210 		if (*s == 'n') {
211 			/*
212 			 * Just use BOOTP/RARP to configure system;
213 			 * Do not use TFTP to load the bootfile.
214 			 */
215 			NetState = NETLOOP_SUCCESS;
216 			return;
217 		}
218 #if defined(CONFIG_CMD_NFS)
219 		if (strcmp(s, "NFS") == 0) {
220 			/*
221 			 * Use NFS to load the bootfile.
222 			 */
223 			NfsStart();
224 			return;
225 		}
226 #endif
227 	}
228 	TftpStart(TFTPGET);
229 }
230 
231 static void NetInitLoop(enum proto_t protocol)
232 {
233 	static int env_changed_id;
234 	int env_id = get_env_id();
235 
236 	/* update only when the environment has changed */
237 	if (env_changed_id != env_id) {
238 		NetOurIP = getenv_IPaddr("ipaddr");
239 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
240 		NetOurSubnetMask = getenv_IPaddr("netmask");
241 		NetServerIP = getenv_IPaddr("serverip");
242 		NetOurNativeVLAN = getenv_VLAN("nvlan");
243 		NetOurVLAN = getenv_VLAN("vlan");
244 #if defined(CONFIG_CMD_DNS)
245 		NetOurDNSIP = getenv_IPaddr("dnsip");
246 #endif
247 		env_changed_id = env_id;
248 	}
249 
250 	return;
251 }
252 
253 /**********************************************************************/
254 /*
255  *	Main network processing loop.
256  */
257 
258 int NetLoop(enum proto_t protocol)
259 {
260 	bd_t *bd = gd->bd;
261 	int ret = -1;
262 
263 	NetRestarted = 0;
264 	NetDevExists = 0;
265 
266 	NetTxPacket = NULL;
267 	NetTryCount = 1;
268 
269 	ArpInit();
270 
271 	if (!NetTxPacket) {
272 		int	i;
273 		/*
274 		 *	Setup packet buffers, aligned correctly.
275 		 */
276 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
277 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
278 		for (i = 0; i < PKTBUFSRX; i++)
279 			NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
280 	}
281 
282 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
283 	eth_halt();
284 	eth_set_current();
285 	if (eth_init(bd) < 0) {
286 		eth_halt();
287 		return -1;
288 	}
289 
290 restart:
291 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
292 
293 	NetState = NETLOOP_CONTINUE;
294 
295 	/*
296 	 *	Start the ball rolling with the given start function.  From
297 	 *	here on, this code is a state machine driven by received
298 	 *	packets and timer events.
299 	 */
300 	NetInitLoop(protocol);
301 
302 	switch (net_check_prereq(protocol)) {
303 	case 1:
304 		/* network not configured */
305 		eth_halt();
306 		return -1;
307 
308 	case 2:
309 		/* network device not configured */
310 		break;
311 
312 	case 0:
313 		NetDevExists = 1;
314 		NetBootFileXferSize = 0;
315 		switch (protocol) {
316 		case TFTPGET:
317 #ifdef CONFIG_CMD_TFTPPUT
318 		case TFTPPUT:
319 #endif
320 			/* always use ARP to get server ethernet address */
321 			TftpStart(protocol);
322 			break;
323 #ifdef CONFIG_CMD_TFTPSRV
324 		case TFTPSRV:
325 			TftpStartServer();
326 			break;
327 #endif
328 #if defined(CONFIG_CMD_DHCP)
329 		case DHCP:
330 			BootpTry = 0;
331 			NetOurIP = 0;
332 			DhcpRequest();		/* Basically same as BOOTP */
333 			break;
334 #endif
335 
336 		case BOOTP:
337 			BootpTry = 0;
338 			NetOurIP = 0;
339 			BootpRequest();
340 			break;
341 
342 #if defined(CONFIG_CMD_RARP)
343 		case RARP:
344 			RarpTry = 0;
345 			NetOurIP = 0;
346 			RarpRequest();
347 			break;
348 #endif
349 #if defined(CONFIG_CMD_PING)
350 		case PING:
351 			ping_start();
352 			break;
353 #endif
354 #if defined(CONFIG_CMD_NFS)
355 		case NFS:
356 			NfsStart();
357 			break;
358 #endif
359 #if defined(CONFIG_CMD_CDP)
360 		case CDP:
361 			CDPStart();
362 			break;
363 #endif
364 #ifdef CONFIG_NETCONSOLE
365 		case NETCONS:
366 			NcStart();
367 			break;
368 #endif
369 #if defined(CONFIG_CMD_SNTP)
370 		case SNTP:
371 			SntpStart();
372 			break;
373 #endif
374 #if defined(CONFIG_CMD_DNS)
375 		case DNS:
376 			DnsStart();
377 			break;
378 #endif
379 		default:
380 			break;
381 		}
382 
383 		break;
384 	}
385 
386 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
387 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
388 	defined(CONFIG_STATUS_LED)			&& \
389 	defined(STATUS_LED_RED)
390 	/*
391 	 * Echo the inverted link state to the fault LED.
392 	 */
393 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
394 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
395 	else
396 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
397 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
398 #endif /* CONFIG_MII, ... */
399 
400 	/*
401 	 *	Main packet reception loop.  Loop receiving packets until
402 	 *	someone sets `NetState' to a state that terminates.
403 	 */
404 	for (;;) {
405 		WATCHDOG_RESET();
406 #ifdef CONFIG_SHOW_ACTIVITY
407 		show_activity(1);
408 #endif
409 		/*
410 		 *	Check the ethernet for a new packet.  The ethernet
411 		 *	receive routine will process it.
412 		 */
413 		eth_rx();
414 
415 		/*
416 		 *	Abort if ctrl-c was pressed.
417 		 */
418 		if (ctrlc()) {
419 			eth_halt();
420 			puts("\nAbort\n");
421 			goto done;
422 		}
423 
424 		ArpTimeoutCheck();
425 
426 		/*
427 		 *	Check for a timeout, and run the timeout handler
428 		 *	if we have one.
429 		 */
430 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
431 			thand_f *x;
432 
433 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
434 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
435 	defined(CONFIG_STATUS_LED)			&& \
436 	defined(STATUS_LED_RED)
437 			/*
438 			 * Echo the inverted link state to the fault LED.
439 			 */
440 			if (miiphy_link(eth_get_dev()->name,
441 				       CONFIG_SYS_FAULT_MII_ADDR)) {
442 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
443 			} else {
444 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
445 			}
446 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
447 #endif /* CONFIG_MII, ... */
448 			x = timeHandler;
449 			timeHandler = (thand_f *)0;
450 			(*x)();
451 		}
452 
453 
454 		switch (NetState) {
455 
456 		case NETLOOP_RESTART:
457 			NetRestarted = 1;
458 			goto restart;
459 
460 		case NETLOOP_SUCCESS:
461 			if (NetBootFileXferSize > 0) {
462 				char buf[20];
463 				printf("Bytes transferred = %ld (%lx hex)\n",
464 					NetBootFileXferSize,
465 					NetBootFileXferSize);
466 				sprintf(buf, "%lX", NetBootFileXferSize);
467 				setenv("filesize", buf);
468 
469 				sprintf(buf, "%lX", (unsigned long)load_addr);
470 				setenv("fileaddr", buf);
471 			}
472 			eth_halt();
473 			ret = NetBootFileXferSize;
474 			goto done;
475 
476 		case NETLOOP_FAIL:
477 			goto done;
478 		}
479 	}
480 
481 done:
482 #ifdef CONFIG_CMD_TFTPPUT
483 	/* Clear out the handlers */
484 	NetSetHandler(NULL);
485 	net_set_icmp_handler(NULL);
486 #endif
487 	return ret;
488 }
489 
490 /**********************************************************************/
491 
492 static void
493 startAgainTimeout(void)
494 {
495 	NetState = NETLOOP_RESTART;
496 }
497 
498 static void
499 startAgainHandler(uchar *pkt, unsigned dest, IPaddr_t sip,
500 		  unsigned src, unsigned len)
501 {
502 	/* Totally ignore the packet */
503 }
504 
505 void NetStartAgain(void)
506 {
507 	char *nretry;
508 	int retry_forever = 0;
509 	unsigned long retrycnt = 0;
510 
511 	nretry = getenv("netretry");
512 	if (nretry) {
513 		if (!strcmp(nretry, "yes"))
514 			retry_forever = 1;
515 		else if (!strcmp(nretry, "no"))
516 			retrycnt = 0;
517 		else if (!strcmp(nretry, "once"))
518 			retrycnt = 1;
519 		else
520 			retrycnt = simple_strtoul(nretry, NULL, 0);
521 	} else
522 		retry_forever = 1;
523 
524 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
525 		eth_halt();
526 		NetState = NETLOOP_FAIL;
527 		return;
528 	}
529 
530 	NetTryCount++;
531 
532 	eth_halt();
533 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
534 	eth_try_another(!NetRestarted);
535 #endif
536 	eth_init(gd->bd);
537 	if (NetRestartWrap) {
538 		NetRestartWrap = 0;
539 		if (NetDevExists) {
540 			NetSetTimeout(10000UL, startAgainTimeout);
541 			NetSetHandler(startAgainHandler);
542 		} else {
543 			NetState = NETLOOP_FAIL;
544 		}
545 	} else {
546 		NetState = NETLOOP_RESTART;
547 	}
548 }
549 
550 /**********************************************************************/
551 /*
552  *	Miscelaneous bits.
553  */
554 
555 rxhand_f *
556 NetGetHandler(void)
557 {
558 	return packetHandler;
559 }
560 
561 
562 void
563 NetSetHandler(rxhand_f *f)
564 {
565 	packetHandler = f;
566 }
567 
568 #ifdef CONFIG_CMD_TFTPPUT
569 void net_set_icmp_handler(rxhand_icmp_f *f)
570 {
571 	packet_icmp_handler = f;
572 }
573 #endif
574 
575 void
576 NetSetTimeout(ulong iv, thand_f *f)
577 {
578 	if (iv == 0) {
579 		timeHandler = (thand_f *)0;
580 	} else {
581 		timeHandler = f;
582 		timeStart = get_timer(0);
583 		timeDelta = iv;
584 	}
585 }
586 
587 
588 void
589 NetSendPacket(uchar *pkt, int len)
590 {
591 	(void) eth_send(pkt, len);
592 }
593 
594 int
595 NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport, int len)
596 {
597 	uchar *pkt;
598 
599 	/* convert to new style broadcast */
600 	if (dest == 0)
601 		dest = 0xFFFFFFFF;
602 
603 	/* if broadcast, make the ether address a broadcast and don't do ARP */
604 	if (dest == 0xFFFFFFFF)
605 		ether = NetBcastAddr;
606 
607 	/*
608 	 * if MAC address was not discovered yet, save the packet and do
609 	 * an ARP request
610 	 */
611 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
612 
613 		debug("sending ARP for %08x\n", dest);
614 
615 		NetArpWaitPacketIP = dest;
616 		NetArpWaitPacketMAC = ether;
617 
618 		pkt = NetArpWaitTxPacket;
619 		pkt += NetSetEther(pkt, NetArpWaitPacketMAC, PROT_IP);
620 
621 		NetSetIP(pkt, dest, dport, sport, len);
622 		memcpy(pkt + IP_UDP_HDR_SIZE, (uchar *)NetTxPacket +
623 		       (pkt - (uchar *)NetArpWaitTxPacket) +
624 		       IP_UDP_HDR_SIZE, len);
625 
626 		/* size of the waiting packet */
627 		NetArpWaitTxPacketSize = (pkt - NetArpWaitTxPacket) +
628 			IP_UDP_HDR_SIZE + len;
629 
630 		/* and do the ARP request */
631 		NetArpWaitTry = 1;
632 		NetArpWaitTimerStart = get_timer(0);
633 		ArpRequest();
634 		return 1;	/* waiting */
635 	}
636 
637 	debug("sending UDP to %08x/%pM\n", dest, ether);
638 
639 	pkt = (uchar *)NetTxPacket;
640 	pkt += NetSetEther(pkt, ether, PROT_IP);
641 	NetSetIP(pkt, dest, dport, sport, len);
642 	eth_send(NetTxPacket, (pkt - NetTxPacket) + IP_UDP_HDR_SIZE + len);
643 
644 	return 0;	/* transmitted */
645 }
646 
647 #ifdef CONFIG_IP_DEFRAG
648 /*
649  * This function collects fragments in a single packet, according
650  * to the algorithm in RFC815. It returns NULL or the pointer to
651  * a complete packet, in static storage
652  */
653 #ifndef CONFIG_NET_MAXDEFRAG
654 #define CONFIG_NET_MAXDEFRAG 16384
655 #endif
656 /*
657  * MAXDEFRAG, above, is chosen in the config file and  is real data
658  * so we need to add the NFS overhead, which is more than TFTP.
659  * To use sizeof in the internal unnamed structures, we need a real
660  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
661  * The compiler doesn't complain nor allocates the actual structure
662  */
663 static struct rpc_t rpc_specimen;
664 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
665 
666 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
667 
668 /*
669  * this is the packet being assembled, either data or frag control.
670  * Fragments go by 8 bytes, so this union must be 8 bytes long
671  */
672 struct hole {
673 	/* first_byte is address of this structure */
674 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
675 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
676 	u16 prev_hole;	/* index of prev, 0 == none */
677 	u16 unused;
678 };
679 
680 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
681 {
682 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
683 	static u16 first_hole, total_len;
684 	struct hole *payload, *thisfrag, *h, *newh;
685 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
686 	uchar *indata = (uchar *)ip;
687 	int offset8, start, len, done = 0;
688 	u16 ip_off = ntohs(ip->ip_off);
689 
690 	/* payload starts after IP header, this fragment is in there */
691 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
692 	offset8 =  (ip_off & IP_OFFS);
693 	thisfrag = payload + offset8;
694 	start = offset8 * 8;
695 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
696 
697 	if (start + len > IP_MAXUDP) /* fragment extends too far */
698 		return NULL;
699 
700 	if (!total_len || localip->ip_id != ip->ip_id) {
701 		/* new (or different) packet, reset structs */
702 		total_len = 0xffff;
703 		payload[0].last_byte = ~0;
704 		payload[0].next_hole = 0;
705 		payload[0].prev_hole = 0;
706 		first_hole = 0;
707 		/* any IP header will work, copy the first we received */
708 		memcpy(localip, ip, IP_HDR_SIZE);
709 	}
710 
711 	/*
712 	 * What follows is the reassembly algorithm. We use the payload
713 	 * array as a linked list of hole descriptors, as each hole starts
714 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
715 	 * so it is represented as byte count, not as 8-byte blocks.
716 	 */
717 
718 	h = payload + first_hole;
719 	while (h->last_byte < start) {
720 		if (!h->next_hole) {
721 			/* no hole that far away */
722 			return NULL;
723 		}
724 		h = payload + h->next_hole;
725 	}
726 
727 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
728 	if (offset8 + ((len + 7) / 8) <= h - payload) {
729 		/* no overlap with holes (dup fragment?) */
730 		return NULL;
731 	}
732 
733 	if (!(ip_off & IP_FLAGS_MFRAG)) {
734 		/* no more fragmentss: truncate this (last) hole */
735 		total_len = start + len;
736 		h->last_byte = start + len;
737 	}
738 
739 	/*
740 	 * There is some overlap: fix the hole list. This code doesn't
741 	 * deal with a fragment that overlaps with two different holes
742 	 * (thus being a superset of a previously-received fragment).
743 	 */
744 
745 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
746 		/* complete overlap with hole: remove hole */
747 		if (!h->prev_hole && !h->next_hole) {
748 			/* last remaining hole */
749 			done = 1;
750 		} else if (!h->prev_hole) {
751 			/* first hole */
752 			first_hole = h->next_hole;
753 			payload[h->next_hole].prev_hole = 0;
754 		} else if (!h->next_hole) {
755 			/* last hole */
756 			payload[h->prev_hole].next_hole = 0;
757 		} else {
758 			/* in the middle of the list */
759 			payload[h->next_hole].prev_hole = h->prev_hole;
760 			payload[h->prev_hole].next_hole = h->next_hole;
761 		}
762 
763 	} else if (h->last_byte <= start + len) {
764 		/* overlaps with final part of the hole: shorten this hole */
765 		h->last_byte = start;
766 
767 	} else if (h >= thisfrag) {
768 		/* overlaps with initial part of the hole: move this hole */
769 		newh = thisfrag + (len / 8);
770 		*newh = *h;
771 		h = newh;
772 		if (h->next_hole)
773 			payload[h->next_hole].prev_hole = (h - payload);
774 		if (h->prev_hole)
775 			payload[h->prev_hole].next_hole = (h - payload);
776 		else
777 			first_hole = (h - payload);
778 
779 	} else {
780 		/* fragment sits in the middle: split the hole */
781 		newh = thisfrag + (len / 8);
782 		*newh = *h;
783 		h->last_byte = start;
784 		h->next_hole = (newh - payload);
785 		newh->prev_hole = (h - payload);
786 		if (newh->next_hole)
787 			payload[newh->next_hole].prev_hole = (newh - payload);
788 	}
789 
790 	/* finally copy this fragment and possibly return whole packet */
791 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
792 	if (!done)
793 		return NULL;
794 
795 	localip->ip_len = htons(total_len);
796 	*lenp = total_len + IP_HDR_SIZE;
797 	return localip;
798 }
799 
800 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
801 {
802 	u16 ip_off = ntohs(ip->ip_off);
803 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
804 		return ip; /* not a fragment */
805 	return __NetDefragment(ip, lenp);
806 }
807 
808 #else /* !CONFIG_IP_DEFRAG */
809 
810 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
811 {
812 	u16 ip_off = ntohs(ip->ip_off);
813 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
814 		return ip; /* not a fragment */
815 	return NULL;
816 }
817 #endif
818 
819 /**
820  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
821  * drop others.
822  *
823  * @parma ip	IP packet containing the ICMP
824  */
825 static void receive_icmp(struct ip_udp_hdr *ip, int len,
826 			IPaddr_t src_ip, struct ethernet_hdr *et)
827 {
828 	ICMP_t *icmph = (ICMP_t *)&ip->udp_src;
829 
830 	switch (icmph->type) {
831 	case ICMP_REDIRECT:
832 		if (icmph->code != ICMP_REDIR_HOST)
833 			return;
834 		printf(" ICMP Host Redirect to %pI4 ",
835 			&icmph->un.gateway);
836 		break;
837 	default:
838 #if defined(CONFIG_CMD_PING)
839 		ping_receive(et, ip, len);
840 #endif
841 #ifdef CONFIG_CMD_TFTPPUT
842 		if (packet_icmp_handler)
843 			packet_icmp_handler(icmph->type, icmph->code,
844 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
845 				icmph->un.data, ntohs(ip->udp_len));
846 #endif
847 		break;
848 	}
849 }
850 
851 void
852 NetReceive(uchar *inpkt, int len)
853 {
854 	struct ethernet_hdr *et;
855 	struct ip_udp_hdr *ip;
856 	IPaddr_t tmp;
857 	IPaddr_t src_ip;
858 	int	x;
859 #if defined(CONFIG_CMD_CDP)
860 	int iscdp;
861 #endif
862 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
863 
864 	debug("packet received\n");
865 
866 	NetRxPacket = inpkt;
867 	NetRxPacketLen = len;
868 	et = (struct ethernet_hdr *)inpkt;
869 
870 	/* too small packet? */
871 	if (len < ETHER_HDR_SIZE)
872 		return;
873 
874 #ifdef CONFIG_API
875 	if (push_packet) {
876 		(*push_packet)(inpkt, len);
877 		return;
878 	}
879 #endif
880 
881 #if defined(CONFIG_CMD_CDP)
882 	/* keep track if packet is CDP */
883 	iscdp = is_cdp_packet(et->et_dest);
884 #endif
885 
886 	myvlanid = ntohs(NetOurVLAN);
887 	if (myvlanid == (ushort)-1)
888 		myvlanid = VLAN_NONE;
889 	mynvlanid = ntohs(NetOurNativeVLAN);
890 	if (mynvlanid == (ushort)-1)
891 		mynvlanid = VLAN_NONE;
892 
893 	x = ntohs(et->et_protlen);
894 
895 	debug("packet received\n");
896 
897 	if (x < 1514) {
898 		struct e802_hdr *et802 = (struct e802_hdr *)et;
899 		/*
900 		 *	Got a 802 packet.  Check the other protocol field.
901 		 */
902 		x = ntohs(et802->et_prot);
903 
904 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
905 		len -= E802_HDR_SIZE;
906 
907 	} else if (x != PROT_VLAN) {	/* normal packet */
908 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
909 		len -= ETHER_HDR_SIZE;
910 
911 	} else {			/* VLAN packet */
912 		struct vlan_ethernet_hdr *vet =
913 			(struct vlan_ethernet_hdr *)et;
914 
915 		debug("VLAN packet received\n");
916 
917 		/* too small packet? */
918 		if (len < VLAN_ETHER_HDR_SIZE)
919 			return;
920 
921 		/* if no VLAN active */
922 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
923 #if defined(CONFIG_CMD_CDP)
924 				&& iscdp == 0
925 #endif
926 				)
927 			return;
928 
929 		cti = ntohs(vet->vet_tag);
930 		vlanid = cti & VLAN_IDMASK;
931 		x = ntohs(vet->vet_type);
932 
933 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
934 		len -= VLAN_ETHER_HDR_SIZE;
935 	}
936 
937 	debug("Receive from protocol 0x%x\n", x);
938 
939 #if defined(CONFIG_CMD_CDP)
940 	if (iscdp) {
941 		CDPHandler((uchar *)ip, len);
942 		return;
943 	}
944 #endif
945 
946 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
947 		if (vlanid == VLAN_NONE)
948 			vlanid = (mynvlanid & VLAN_IDMASK);
949 		/* not matched? */
950 		if (vlanid != (myvlanid & VLAN_IDMASK))
951 			return;
952 	}
953 
954 	switch (x) {
955 
956 	case PROT_ARP:
957 		ArpReceive(et, ip, len);
958 		break;
959 
960 #ifdef CONFIG_CMD_RARP
961 	case PROT_RARP:
962 		rarp_receive(ip, len);
963 		break;
964 #endif
965 	case PROT_IP:
966 		debug("Got IP\n");
967 		/* Before we start poking the header, make sure it is there */
968 		if (len < IP_UDP_HDR_SIZE) {
969 			debug("len bad %d < %lu\n", len,
970 				(ulong)IP_UDP_HDR_SIZE);
971 			return;
972 		}
973 		/* Check the packet length */
974 		if (len < ntohs(ip->ip_len)) {
975 			printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
976 			return;
977 		}
978 		len = ntohs(ip->ip_len);
979 		debug("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
980 
981 		/* Can't deal with anything except IPv4 */
982 		if ((ip->ip_hl_v & 0xf0) != 0x40)
983 			return;
984 		/* Can't deal with IP options (headers != 20 bytes) */
985 		if ((ip->ip_hl_v & 0x0f) > 0x05)
986 			return;
987 		/* Check the Checksum of the header */
988 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
989 			puts("checksum bad\n");
990 			return;
991 		}
992 		/* If it is not for us, ignore it */
993 		tmp = NetReadIP(&ip->ip_dst);
994 		if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) {
995 #ifdef CONFIG_MCAST_TFTP
996 			if (Mcast_addr != tmp)
997 #endif
998 				return;
999 		}
1000 		/* Read source IP address for later use */
1001 		src_ip = NetReadIP(&ip->ip_src);
1002 		/*
1003 		 * The function returns the unchanged packet if it's not
1004 		 * a fragment, and either the complete packet or NULL if
1005 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1006 		 */
1007 		ip = NetDefragment(ip, &len);
1008 		if (!ip)
1009 			return;
1010 		/*
1011 		 * watch for ICMP host redirects
1012 		 *
1013 		 * There is no real handler code (yet). We just watch
1014 		 * for ICMP host redirect messages. In case anybody
1015 		 * sees these messages: please contact me
1016 		 * (wd@denx.de), or - even better - send me the
1017 		 * necessary fixes :-)
1018 		 *
1019 		 * Note: in all cases where I have seen this so far
1020 		 * it was a problem with the router configuration,
1021 		 * for instance when a router was configured in the
1022 		 * BOOTP reply, but the TFTP server was on the same
1023 		 * subnet. So this is probably a warning that your
1024 		 * configuration might be wrong. But I'm not really
1025 		 * sure if there aren't any other situations.
1026 		 *
1027 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1028 		 * we send a tftp packet to a dead connection, or when
1029 		 * there is no server at the other end.
1030 		 */
1031 		if (ip->ip_p == IPPROTO_ICMP) {
1032 			receive_icmp(ip, len, src_ip, et);
1033 			return;
1034 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1035 			return;
1036 		}
1037 
1038 #ifdef CONFIG_UDP_CHECKSUM
1039 		if (ip->udp_xsum != 0) {
1040 			ulong   xsum;
1041 			ushort *sumptr;
1042 			ushort  sumlen;
1043 
1044 			xsum  = ip->ip_p;
1045 			xsum += (ntohs(ip->udp_len));
1046 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1047 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1048 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1049 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1050 
1051 			sumlen = ntohs(ip->udp_len);
1052 			sumptr = (ushort *) &(ip->udp_src);
1053 
1054 			while (sumlen > 1) {
1055 				ushort sumdata;
1056 
1057 				sumdata = *sumptr++;
1058 				xsum += ntohs(sumdata);
1059 				sumlen -= 2;
1060 			}
1061 			if (sumlen > 0) {
1062 				ushort sumdata;
1063 
1064 				sumdata = *(unsigned char *) sumptr;
1065 				sumdata = (sumdata << 8) & 0xff00;
1066 				xsum += sumdata;
1067 			}
1068 			while ((xsum >> 16) != 0) {
1069 				xsum = (xsum & 0x0000ffff) +
1070 				       ((xsum >> 16) & 0x0000ffff);
1071 			}
1072 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1073 				printf(" UDP wrong checksum %08lx %08x\n",
1074 					xsum, ntohs(ip->udp_xsum));
1075 				return;
1076 			}
1077 		}
1078 #endif
1079 
1080 
1081 #ifdef CONFIG_NETCONSOLE
1082 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1083 					ntohs(ip->udp_dst),
1084 					ntohs(ip->udp_src),
1085 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1086 #endif
1087 		/*
1088 		 *	IP header OK.  Pass the packet to the current handler.
1089 		 */
1090 		(*packetHandler)((uchar *)ip + IP_UDP_HDR_SIZE,
1091 					ntohs(ip->udp_dst),
1092 					src_ip,
1093 					ntohs(ip->udp_src),
1094 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1095 		break;
1096 	}
1097 }
1098 
1099 
1100 /**********************************************************************/
1101 
1102 static int net_check_prereq(enum proto_t protocol)
1103 {
1104 	switch (protocol) {
1105 		/* Fall through */
1106 #if defined(CONFIG_CMD_PING)
1107 	case PING:
1108 		if (NetPingIP == 0) {
1109 			puts("*** ERROR: ping address not given\n");
1110 			return 1;
1111 		}
1112 		goto common;
1113 #endif
1114 #if defined(CONFIG_CMD_SNTP)
1115 	case SNTP:
1116 		if (NetNtpServerIP == 0) {
1117 			puts("*** ERROR: NTP server address not given\n");
1118 			return 1;
1119 		}
1120 		goto common;
1121 #endif
1122 #if defined(CONFIG_CMD_DNS)
1123 	case DNS:
1124 		if (NetOurDNSIP == 0) {
1125 			puts("*** ERROR: DNS server address not given\n");
1126 			return 1;
1127 		}
1128 		goto common;
1129 #endif
1130 #if defined(CONFIG_CMD_NFS)
1131 	case NFS:
1132 #endif
1133 	case TFTPGET:
1134 	case TFTPPUT:
1135 		if (NetServerIP == 0) {
1136 			puts("*** ERROR: `serverip' not set\n");
1137 			return 1;
1138 		}
1139 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1140 	defined(CONFIG_CMD_DNS)
1141 common:
1142 #endif
1143 		/* Fall through */
1144 
1145 	case NETCONS:
1146 	case TFTPSRV:
1147 		if (NetOurIP == 0) {
1148 			puts("*** ERROR: `ipaddr' not set\n");
1149 			return 1;
1150 		}
1151 		/* Fall through */
1152 
1153 #ifdef CONFIG_CMD_RARP
1154 	case RARP:
1155 #endif
1156 	case BOOTP:
1157 	case CDP:
1158 	case DHCP:
1159 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1160 			int num = eth_get_dev_index();
1161 
1162 			switch (num) {
1163 			case -1:
1164 				puts("*** ERROR: No ethernet found.\n");
1165 				return 1;
1166 			case 0:
1167 				puts("*** ERROR: `ethaddr' not set\n");
1168 				break;
1169 			default:
1170 				printf("*** ERROR: `eth%daddr' not set\n",
1171 					num);
1172 				break;
1173 			}
1174 
1175 			NetStartAgain();
1176 			return 2;
1177 		}
1178 		/* Fall through */
1179 	default:
1180 		return 0;
1181 	}
1182 	return 0;		/* OK */
1183 }
1184 /**********************************************************************/
1185 
1186 int
1187 NetCksumOk(uchar *ptr, int len)
1188 {
1189 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1190 }
1191 
1192 
1193 unsigned
1194 NetCksum(uchar *ptr, int len)
1195 {
1196 	ulong	xsum;
1197 	ushort *p = (ushort *)ptr;
1198 
1199 	xsum = 0;
1200 	while (len-- > 0)
1201 		xsum += *p++;
1202 	xsum = (xsum & 0xffff) + (xsum >> 16);
1203 	xsum = (xsum & 0xffff) + (xsum >> 16);
1204 	return xsum & 0xffff;
1205 }
1206 
1207 int
1208 NetEthHdrSize(void)
1209 {
1210 	ushort myvlanid;
1211 
1212 	myvlanid = ntohs(NetOurVLAN);
1213 	if (myvlanid == (ushort)-1)
1214 		myvlanid = VLAN_NONE;
1215 
1216 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1217 		VLAN_ETHER_HDR_SIZE;
1218 }
1219 
1220 int
1221 NetSetEther(uchar *xet, uchar * addr, uint prot)
1222 {
1223 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1224 	ushort myvlanid;
1225 
1226 	myvlanid = ntohs(NetOurVLAN);
1227 	if (myvlanid == (ushort)-1)
1228 		myvlanid = VLAN_NONE;
1229 
1230 	memcpy(et->et_dest, addr, 6);
1231 	memcpy(et->et_src, NetOurEther, 6);
1232 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1233 		et->et_protlen = htons(prot);
1234 		return ETHER_HDR_SIZE;
1235 	} else {
1236 		struct vlan_ethernet_hdr *vet =
1237 			(struct vlan_ethernet_hdr *)xet;
1238 
1239 		vet->vet_vlan_type = htons(PROT_VLAN);
1240 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1241 		vet->vet_type = htons(prot);
1242 		return VLAN_ETHER_HDR_SIZE;
1243 	}
1244 }
1245 
1246 void NetSetIP(uchar *xip, IPaddr_t dest, int dport, int sport, int len)
1247 {
1248 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)xip;
1249 
1250 	/*
1251 	 *	If the data is an odd number of bytes, zero the
1252 	 *	byte after the last byte so that the checksum
1253 	 *	will work.
1254 	 */
1255 	if (len & 1)
1256 		xip[IP_UDP_HDR_SIZE + len] = 0;
1257 
1258 	/*
1259 	 *	Construct an IP and UDP header.
1260 	 *	(need to set no fragment bit - XXX)
1261 	 */
1262 	/* IP_HDR_SIZE / 4 (not including UDP) */
1263 	ip->ip_hl_v  = 0x45;
1264 	ip->ip_tos   = 0;
1265 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1266 	ip->ip_id    = htons(NetIPID++);
1267 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1268 	ip->ip_ttl   = 255;
1269 	ip->ip_p     = 17;		/* UDP */
1270 	ip->ip_sum   = 0;
1271 	/* already in network byte order */
1272 	NetCopyIP((void *)&ip->ip_src, &NetOurIP);
1273 	/* - "" - */
1274 	NetCopyIP((void *)&ip->ip_dst, &dest);
1275 	ip->udp_src  = htons(sport);
1276 	ip->udp_dst  = htons(dport);
1277 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1278 	ip->udp_xsum = 0;
1279 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE / 2);
1280 }
1281 
1282 void copy_filename(char *dst, const char *src, int size)
1283 {
1284 	if (*src && (*src == '"')) {
1285 		++src;
1286 		--size;
1287 	}
1288 
1289 	while ((--size > 0) && *src && (*src != '"'))
1290 		*dst++ = *src++;
1291 	*dst = '\0';
1292 }
1293 
1294 #if	defined(CONFIG_CMD_NFS)		|| \
1295 	defined(CONFIG_CMD_SNTP)	|| \
1296 	defined(CONFIG_CMD_DNS)
1297 /*
1298  * make port a little random (1024-17407)
1299  * This keeps the math somewhat trivial to compute, and seems to work with
1300  * all supported protocols/clients/servers
1301  */
1302 unsigned int random_port(void)
1303 {
1304 	return 1024 + (get_timer(0) % 0x4000);
1305 }
1306 #endif
1307 
1308 void ip_to_string(IPaddr_t x, char *s)
1309 {
1310 	x = ntohl(x);
1311 	sprintf(s, "%d.%d.%d.%d",
1312 		(int) ((x >> 24) & 0xff),
1313 		(int) ((x >> 16) & 0xff),
1314 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1315 	);
1316 }
1317 
1318 void VLAN_to_string(ushort x, char *s)
1319 {
1320 	x = ntohs(x);
1321 
1322 	if (x == (ushort)-1)
1323 		x = VLAN_NONE;
1324 
1325 	if (x == VLAN_NONE)
1326 		strcpy(s, "none");
1327 	else
1328 		sprintf(s, "%d", x & VLAN_IDMASK);
1329 }
1330 
1331 ushort string_to_VLAN(const char *s)
1332 {
1333 	ushort id;
1334 
1335 	if (s == NULL)
1336 		return htons(VLAN_NONE);
1337 
1338 	if (*s < '0' || *s > '9')
1339 		id = VLAN_NONE;
1340 	else
1341 		id = (ushort)simple_strtoul(s, NULL, 10);
1342 
1343 	return htons(id);
1344 }
1345 
1346 ushort getenv_VLAN(char *var)
1347 {
1348 	return string_to_VLAN(getenv(var));
1349 }
1350