xref: /rk3399_rockchip-uboot/net/net.c (revision d280d3f430a4056e7baf66dc4be705dc8cc9bd37)
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 #ifdef CONFIG_CMD_RARP
86 #include "rarp.h"
87 #endif
88 #include "nfs.h"
89 #ifdef CONFIG_STATUS_LED
90 #include <status_led.h>
91 #include <miiphy.h>
92 #endif
93 #if defined(CONFIG_CMD_SNTP)
94 #include "sntp.h"
95 #endif
96 #include "cdp.h"
97 #if defined(CONFIG_CMD_DNS)
98 #include "dns.h"
99 #endif
100 
101 DECLARE_GLOBAL_DATA_PTR;
102 
103 /** BOOTP EXTENTIONS **/
104 
105 /* Our subnet mask (0=unknown) */
106 IPaddr_t	NetOurSubnetMask;
107 /* Our gateways IP address */
108 IPaddr_t	NetOurGatewayIP;
109 /* Our DNS IP address */
110 IPaddr_t	NetOurDNSIP;
111 #if defined(CONFIG_BOOTP_DNS2)
112 /* Our 2nd DNS IP address */
113 IPaddr_t	NetOurDNS2IP;
114 #endif
115 /* Our NIS domain */
116 char		NetOurNISDomain[32] = {0,};
117 /* Our hostname */
118 char		NetOurHostName[32] = {0,};
119 /* Our bootpath */
120 char		NetOurRootPath[64] = {0,};
121 /* Our bootfile size in blocks */
122 ushort		NetBootFileSize;
123 
124 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
125 IPaddr_t Mcast_addr;
126 #endif
127 
128 /** END OF BOOTP EXTENTIONS **/
129 
130 /* The actual transferred size of the bootfile (in bytes) */
131 ulong		NetBootFileXferSize;
132 /* Our ethernet address */
133 uchar		NetOurEther[6];
134 /* Boot server enet address */
135 uchar		NetServerEther[6];
136 /* Our IP addr (0 = unknown) */
137 IPaddr_t	NetOurIP;
138 /* Server IP addr (0 = unknown) */
139 IPaddr_t	NetServerIP;
140 /* Current receive packet */
141 uchar *NetRxPacket;
142 /* Current rx packet length */
143 int		NetRxPacketLen;
144 /* IP packet ID */
145 unsigned	NetIPID;
146 /* Ethernet bcast address */
147 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
148 uchar		NetEtherNullAddr[6];
149 #ifdef CONFIG_API
150 void		(*push_packet)(void *, int len) = 0;
151 #endif
152 /* Network loop state */
153 int		NetState;
154 /* Tried all network devices */
155 int		NetRestartWrap;
156 /* Network loop restarted */
157 static int	NetRestarted;
158 /* At least one device configured */
159 static int	NetDevExists;
160 
161 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
162 /* default is without VLAN */
163 ushort		NetOurVLAN = 0xFFFF;
164 /* ditto */
165 ushort		NetOurNativeVLAN = 0xFFFF;
166 
167 /* Boot File name */
168 char		BootFile[128];
169 
170 #if defined(CONFIG_CMD_PING)
171 /* the ip address to ping */
172 IPaddr_t	NetPingIP;
173 
174 static void PingStart(void);
175 #endif
176 
177 #if defined(CONFIG_CMD_SNTP)
178 /* NTP server IP address */
179 IPaddr_t	NetNtpServerIP;
180 /* offset time from UTC */
181 int		NetTimeOffset;
182 #endif
183 
184 uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
185 
186 /* Receive packet */
187 uchar *NetRxPackets[PKTBUFSRX];
188 
189 /* Current RX packet handler */
190 static rxhand_f *packetHandler;
191 #ifdef CONFIG_CMD_TFTPPUT
192 static rxhand_icmp_f *packet_icmp_handler;	/* Current ICMP rx handler */
193 #endif
194 /* Current timeout handler */
195 static thand_f *timeHandler;
196 /* Time base value */
197 static ulong	timeStart;
198 /* Current timeout value */
199 static ulong	timeDelta;
200 /* THE transmit packet */
201 uchar *NetTxPacket;
202 
203 static int net_check_prereq(enum proto_t protocol);
204 
205 static int NetTryCount;
206 
207 /**********************************************************************/
208 
209 /*
210  * Check if autoload is enabled. If so, use either NFS or TFTP to download
211  * the boot file.
212  */
213 void net_auto_load(void)
214 {
215 	const char *s = getenv("autoload");
216 
217 	if (s != NULL) {
218 		if (*s == 'n') {
219 			/*
220 			 * Just use BOOTP/RARP to configure system;
221 			 * Do not use TFTP to load the bootfile.
222 			 */
223 			NetState = NETLOOP_SUCCESS;
224 			return;
225 		}
226 #if defined(CONFIG_CMD_NFS)
227 		if (strcmp(s, "NFS") == 0) {
228 			/*
229 			 * Use NFS to load the bootfile.
230 			 */
231 			NfsStart();
232 			return;
233 		}
234 #endif
235 	}
236 	TftpStart(TFTPGET);
237 }
238 
239 static void NetInitLoop(enum proto_t protocol)
240 {
241 	static int env_changed_id;
242 	int env_id = get_env_id();
243 
244 	/* update only when the environment has changed */
245 	if (env_changed_id != env_id) {
246 		NetOurIP = getenv_IPaddr("ipaddr");
247 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
248 		NetOurSubnetMask = getenv_IPaddr("netmask");
249 		NetServerIP = getenv_IPaddr("serverip");
250 		NetOurNativeVLAN = getenv_VLAN("nvlan");
251 		NetOurVLAN = getenv_VLAN("vlan");
252 #if defined(CONFIG_CMD_DNS)
253 		NetOurDNSIP = getenv_IPaddr("dnsip");
254 #endif
255 		env_changed_id = env_id;
256 	}
257 
258 	return;
259 }
260 
261 /**********************************************************************/
262 /*
263  *	Main network processing loop.
264  */
265 
266 int NetLoop(enum proto_t protocol)
267 {
268 	bd_t *bd = gd->bd;
269 	int ret = -1;
270 
271 	NetRestarted = 0;
272 	NetDevExists = 0;
273 
274 	NetTxPacket = NULL;
275 	NetTryCount = 1;
276 
277 	ArpInit();
278 
279 	if (!NetTxPacket) {
280 		int	i;
281 		/*
282 		 *	Setup packet buffers, aligned correctly.
283 		 */
284 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
285 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
286 		for (i = 0; i < PKTBUFSRX; i++)
287 			NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
288 	}
289 
290 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
291 	eth_halt();
292 	eth_set_current();
293 	if (eth_init(bd) < 0) {
294 		eth_halt();
295 		return -1;
296 	}
297 
298 restart:
299 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
300 
301 	NetState = NETLOOP_CONTINUE;
302 
303 	/*
304 	 *	Start the ball rolling with the given start function.  From
305 	 *	here on, this code is a state machine driven by received
306 	 *	packets and timer events.
307 	 */
308 	NetInitLoop(protocol);
309 
310 	switch (net_check_prereq(protocol)) {
311 	case 1:
312 		/* network not configured */
313 		eth_halt();
314 		return -1;
315 
316 	case 2:
317 		/* network device not configured */
318 		break;
319 
320 	case 0:
321 		NetDevExists = 1;
322 		NetBootFileXferSize = 0;
323 		switch (protocol) {
324 		case TFTPGET:
325 #ifdef CONFIG_CMD_TFTPPUT
326 		case TFTPPUT:
327 #endif
328 			/* always use ARP to get server ethernet address */
329 			TftpStart(protocol);
330 			break;
331 #ifdef CONFIG_CMD_TFTPSRV
332 		case TFTPSRV:
333 			TftpStartServer();
334 			break;
335 #endif
336 #if defined(CONFIG_CMD_DHCP)
337 		case DHCP:
338 			BootpTry = 0;
339 			NetOurIP = 0;
340 			DhcpRequest();		/* Basically same as BOOTP */
341 			break;
342 #endif
343 
344 		case BOOTP:
345 			BootpTry = 0;
346 			NetOurIP = 0;
347 			BootpRequest();
348 			break;
349 
350 #if defined(CONFIG_CMD_RARP)
351 		case RARP:
352 			RarpTry = 0;
353 			NetOurIP = 0;
354 			RarpRequest();
355 			break;
356 #endif
357 #if defined(CONFIG_CMD_PING)
358 		case PING:
359 			PingStart();
360 			break;
361 #endif
362 #if defined(CONFIG_CMD_NFS)
363 		case NFS:
364 			NfsStart();
365 			break;
366 #endif
367 #if defined(CONFIG_CMD_CDP)
368 		case CDP:
369 			CDPStart();
370 			break;
371 #endif
372 #ifdef CONFIG_NETCONSOLE
373 		case NETCONS:
374 			NcStart();
375 			break;
376 #endif
377 #if defined(CONFIG_CMD_SNTP)
378 		case SNTP:
379 			SntpStart();
380 			break;
381 #endif
382 #if defined(CONFIG_CMD_DNS)
383 		case DNS:
384 			DnsStart();
385 			break;
386 #endif
387 		default:
388 			break;
389 		}
390 
391 		break;
392 	}
393 
394 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
395 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
396 	defined(CONFIG_STATUS_LED)			&& \
397 	defined(STATUS_LED_RED)
398 	/*
399 	 * Echo the inverted link state to the fault LED.
400 	 */
401 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
402 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
403 	else
404 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
405 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
406 #endif /* CONFIG_MII, ... */
407 
408 	/*
409 	 *	Main packet reception loop.  Loop receiving packets until
410 	 *	someone sets `NetState' to a state that terminates.
411 	 */
412 	for (;;) {
413 		WATCHDOG_RESET();
414 #ifdef CONFIG_SHOW_ACTIVITY
415 		show_activity(1);
416 #endif
417 		/*
418 		 *	Check the ethernet for a new packet.  The ethernet
419 		 *	receive routine will process it.
420 		 */
421 		eth_rx();
422 
423 		/*
424 		 *	Abort if ctrl-c was pressed.
425 		 */
426 		if (ctrlc()) {
427 			eth_halt();
428 			puts("\nAbort\n");
429 			goto done;
430 		}
431 
432 		ArpTimeoutCheck();
433 
434 		/*
435 		 *	Check for a timeout, and run the timeout handler
436 		 *	if we have one.
437 		 */
438 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
439 			thand_f *x;
440 
441 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
442 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
443 	defined(CONFIG_STATUS_LED)			&& \
444 	defined(STATUS_LED_RED)
445 			/*
446 			 * Echo the inverted link state to the fault LED.
447 			 */
448 			if (miiphy_link(eth_get_dev()->name,
449 				       CONFIG_SYS_FAULT_MII_ADDR)) {
450 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
451 			} else {
452 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
453 			}
454 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
455 #endif /* CONFIG_MII, ... */
456 			x = timeHandler;
457 			timeHandler = (thand_f *)0;
458 			(*x)();
459 		}
460 
461 
462 		switch (NetState) {
463 
464 		case NETLOOP_RESTART:
465 			NetRestarted = 1;
466 			goto restart;
467 
468 		case NETLOOP_SUCCESS:
469 			if (NetBootFileXferSize > 0) {
470 				char buf[20];
471 				printf("Bytes transferred = %ld (%lx hex)\n",
472 					NetBootFileXferSize,
473 					NetBootFileXferSize);
474 				sprintf(buf, "%lX", NetBootFileXferSize);
475 				setenv("filesize", buf);
476 
477 				sprintf(buf, "%lX", (unsigned long)load_addr);
478 				setenv("fileaddr", buf);
479 			}
480 			eth_halt();
481 			ret = NetBootFileXferSize;
482 			goto done;
483 
484 		case NETLOOP_FAIL:
485 			goto done;
486 		}
487 	}
488 
489 done:
490 #ifdef CONFIG_CMD_TFTPPUT
491 	/* Clear out the handlers */
492 	NetSetHandler(NULL);
493 	net_set_icmp_handler(NULL);
494 #endif
495 	return ret;
496 }
497 
498 /**********************************************************************/
499 
500 static void
501 startAgainTimeout(void)
502 {
503 	NetState = NETLOOP_RESTART;
504 }
505 
506 static void
507 startAgainHandler(uchar *pkt, unsigned dest, IPaddr_t sip,
508 		  unsigned src, unsigned len)
509 {
510 	/* Totally ignore the packet */
511 }
512 
513 void NetStartAgain(void)
514 {
515 	char *nretry;
516 	int retry_forever = 0;
517 	unsigned long retrycnt = 0;
518 
519 	nretry = getenv("netretry");
520 	if (nretry) {
521 		if (!strcmp(nretry, "yes"))
522 			retry_forever = 1;
523 		else if (!strcmp(nretry, "no"))
524 			retrycnt = 0;
525 		else if (!strcmp(nretry, "once"))
526 			retrycnt = 1;
527 		else
528 			retrycnt = simple_strtoul(nretry, NULL, 0);
529 	} else
530 		retry_forever = 1;
531 
532 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
533 		eth_halt();
534 		NetState = NETLOOP_FAIL;
535 		return;
536 	}
537 
538 	NetTryCount++;
539 
540 	eth_halt();
541 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
542 	eth_try_another(!NetRestarted);
543 #endif
544 	eth_init(gd->bd);
545 	if (NetRestartWrap) {
546 		NetRestartWrap = 0;
547 		if (NetDevExists) {
548 			NetSetTimeout(10000UL, startAgainTimeout);
549 			NetSetHandler(startAgainHandler);
550 		} else {
551 			NetState = NETLOOP_FAIL;
552 		}
553 	} else {
554 		NetState = NETLOOP_RESTART;
555 	}
556 }
557 
558 /**********************************************************************/
559 /*
560  *	Miscelaneous bits.
561  */
562 
563 rxhand_f *
564 NetGetHandler(void)
565 {
566 	return packetHandler;
567 }
568 
569 
570 void
571 NetSetHandler(rxhand_f *f)
572 {
573 	packetHandler = f;
574 }
575 
576 #ifdef CONFIG_CMD_TFTPPUT
577 void net_set_icmp_handler(rxhand_icmp_f *f)
578 {
579 	packet_icmp_handler = f;
580 }
581 #endif
582 
583 void
584 NetSetTimeout(ulong iv, thand_f *f)
585 {
586 	if (iv == 0) {
587 		timeHandler = (thand_f *)0;
588 	} else {
589 		timeHandler = f;
590 		timeStart = get_timer(0);
591 		timeDelta = iv;
592 	}
593 }
594 
595 
596 void
597 NetSendPacket(uchar *pkt, int len)
598 {
599 	(void) eth_send(pkt, len);
600 }
601 
602 int
603 NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport, int len)
604 {
605 	uchar *pkt;
606 
607 	/* convert to new style broadcast */
608 	if (dest == 0)
609 		dest = 0xFFFFFFFF;
610 
611 	/* if broadcast, make the ether address a broadcast and don't do ARP */
612 	if (dest == 0xFFFFFFFF)
613 		ether = NetBcastAddr;
614 
615 	/*
616 	 * if MAC address was not discovered yet, save the packet and do
617 	 * an ARP request
618 	 */
619 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
620 
621 		debug("sending ARP for %08x\n", dest);
622 
623 		NetArpWaitPacketIP = dest;
624 		NetArpWaitPacketMAC = ether;
625 
626 		pkt = NetArpWaitTxPacket;
627 		pkt += NetSetEther(pkt, NetArpWaitPacketMAC, PROT_IP);
628 
629 		NetSetIP(pkt, dest, dport, sport, len);
630 		memcpy(pkt + IP_HDR_SIZE, (uchar *)NetTxPacket +
631 		       (pkt - (uchar *)NetArpWaitTxPacket) + IP_HDR_SIZE, len);
632 
633 		/* size of the waiting packet */
634 		NetArpWaitTxPacketSize = (pkt - NetArpWaitTxPacket) +
635 			IP_HDR_SIZE + len;
636 
637 		/* and do the ARP request */
638 		NetArpWaitTry = 1;
639 		NetArpWaitTimerStart = get_timer(0);
640 		ArpRequest();
641 		return 1;	/* waiting */
642 	}
643 
644 	debug("sending UDP to %08x/%pM\n", dest, ether);
645 
646 	pkt = (uchar *)NetTxPacket;
647 	pkt += NetSetEther(pkt, ether, PROT_IP);
648 	NetSetIP(pkt, dest, dport, sport, len);
649 	(void) eth_send(NetTxPacket, (pkt - NetTxPacket) + IP_HDR_SIZE + len);
650 
651 	return 0;	/* transmitted */
652 }
653 
654 #if defined(CONFIG_CMD_PING)
655 static ushort PingSeqNo;
656 
657 int PingSend(void)
658 {
659 	static uchar mac[6];
660 	IP_t *ip;
661 	ushort *s;
662 	uchar *pkt;
663 
664 	/* XXX always send arp request */
665 
666 	memcpy(mac, NetEtherNullAddr, 6);
667 
668 	debug("sending ARP for %08x\n", NetPingIP);
669 
670 	NetArpWaitPacketIP = NetPingIP;
671 	NetArpWaitPacketMAC = mac;
672 
673 	pkt = NetArpWaitTxPacket;
674 	pkt += NetSetEther(pkt, mac, PROT_IP);
675 
676 	ip = (IP_t *)pkt;
677 
678 	/*
679 	 * Construct an IP and ICMP header.
680 	 * (need to set no fragment bit - XXX)
681 	 */
682 	/* IP_HDR_SIZE / 4 (not including UDP) */
683 	ip->ip_hl_v  = 0x45;
684 	ip->ip_tos   = 0;
685 	ip->ip_len   = htons(IP_HDR_SIZE_NO_UDP + 8);
686 	ip->ip_id    = htons(NetIPID++);
687 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
688 	ip->ip_ttl   = 255;
689 	ip->ip_p     = 0x01;		/* ICMP */
690 	ip->ip_sum   = 0;
691 	/* already in network byte order */
692 	NetCopyIP((void *)&ip->ip_src, &NetOurIP);
693 	/* - "" - */
694 	NetCopyIP((void *)&ip->ip_dst, &NetPingIP);
695 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
696 
697 	s = &ip->udp_src;		/* XXX ICMP starts here */
698 	s[0] = htons(0x0800);		/* echo-request, code */
699 	s[1] = 0;			/* checksum */
700 	s[2] = 0;			/* identifier */
701 	s[3] = htons(PingSeqNo++);	/* sequence number */
702 	s[1] = ~NetCksum((uchar *)s, 8/2);
703 
704 	/* size of the waiting packet */
705 	NetArpWaitTxPacketSize =
706 		(pkt - NetArpWaitTxPacket) + IP_HDR_SIZE_NO_UDP + 8;
707 
708 	/* and do the ARP request */
709 	NetArpWaitTry = 1;
710 	NetArpWaitTimerStart = get_timer(0);
711 	ArpRequest();
712 	return 1;	/* waiting */
713 }
714 
715 static void
716 PingTimeout(void)
717 {
718 	eth_halt();
719 	NetState = NETLOOP_FAIL;	/* we did not get the reply */
720 }
721 
722 static void
723 PingHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
724 	    unsigned len)
725 {
726 	if (sip != NetPingIP)
727 		return;
728 
729 	NetState = NETLOOP_SUCCESS;
730 }
731 
732 static void PingStart(void)
733 {
734 	printf("Using %s device\n", eth_get_name());
735 	NetSetTimeout(10000UL, PingTimeout);
736 	NetSetHandler(PingHandler);
737 
738 	PingSend();
739 }
740 #endif
741 
742 #ifdef CONFIG_IP_DEFRAG
743 /*
744  * This function collects fragments in a single packet, according
745  * to the algorithm in RFC815. It returns NULL or the pointer to
746  * a complete packet, in static storage
747  */
748 #ifndef CONFIG_NET_MAXDEFRAG
749 #define CONFIG_NET_MAXDEFRAG 16384
750 #endif
751 /*
752  * MAXDEFRAG, above, is chosen in the config file and  is real data
753  * so we need to add the NFS overhead, which is more than TFTP.
754  * To use sizeof in the internal unnamed structures, we need a real
755  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
756  * The compiler doesn't complain nor allocates the actual structure
757  */
758 static struct rpc_t rpc_specimen;
759 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
760 
761 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE_NO_UDP)
762 
763 /*
764  * this is the packet being assembled, either data or frag control.
765  * Fragments go by 8 bytes, so this union must be 8 bytes long
766  */
767 struct hole {
768 	/* first_byte is address of this structure */
769 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
770 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
771 	u16 prev_hole;	/* index of prev, 0 == none */
772 	u16 unused;
773 };
774 
775 static IP_t *__NetDefragment(IP_t *ip, int *lenp)
776 {
777 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
778 	static u16 first_hole, total_len;
779 	struct hole *payload, *thisfrag, *h, *newh;
780 	IP_t *localip = (IP_t *)pkt_buff;
781 	uchar *indata = (uchar *)ip;
782 	int offset8, start, len, done = 0;
783 	u16 ip_off = ntohs(ip->ip_off);
784 
785 	/* payload starts after IP header, this fragment is in there */
786 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE_NO_UDP);
787 	offset8 =  (ip_off & IP_OFFS);
788 	thisfrag = payload + offset8;
789 	start = offset8 * 8;
790 	len = ntohs(ip->ip_len) - IP_HDR_SIZE_NO_UDP;
791 
792 	if (start + len > IP_MAXUDP) /* fragment extends too far */
793 		return NULL;
794 
795 	if (!total_len || localip->ip_id != ip->ip_id) {
796 		/* new (or different) packet, reset structs */
797 		total_len = 0xffff;
798 		payload[0].last_byte = ~0;
799 		payload[0].next_hole = 0;
800 		payload[0].prev_hole = 0;
801 		first_hole = 0;
802 		/* any IP header will work, copy the first we received */
803 		memcpy(localip, ip, IP_HDR_SIZE_NO_UDP);
804 	}
805 
806 	/*
807 	 * What follows is the reassembly algorithm. We use the payload
808 	 * array as a linked list of hole descriptors, as each hole starts
809 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
810 	 * so it is represented as byte count, not as 8-byte blocks.
811 	 */
812 
813 	h = payload + first_hole;
814 	while (h->last_byte < start) {
815 		if (!h->next_hole) {
816 			/* no hole that far away */
817 			return NULL;
818 		}
819 		h = payload + h->next_hole;
820 	}
821 
822 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
823 	if (offset8 + ((len + 7) / 8) <= h - payload) {
824 		/* no overlap with holes (dup fragment?) */
825 		return NULL;
826 	}
827 
828 	if (!(ip_off & IP_FLAGS_MFRAG)) {
829 		/* no more fragmentss: truncate this (last) hole */
830 		total_len = start + len;
831 		h->last_byte = start + len;
832 	}
833 
834 	/*
835 	 * There is some overlap: fix the hole list. This code doesn't
836 	 * deal with a fragment that overlaps with two different holes
837 	 * (thus being a superset of a previously-received fragment).
838 	 */
839 
840 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
841 		/* complete overlap with hole: remove hole */
842 		if (!h->prev_hole && !h->next_hole) {
843 			/* last remaining hole */
844 			done = 1;
845 		} else if (!h->prev_hole) {
846 			/* first hole */
847 			first_hole = h->next_hole;
848 			payload[h->next_hole].prev_hole = 0;
849 		} else if (!h->next_hole) {
850 			/* last hole */
851 			payload[h->prev_hole].next_hole = 0;
852 		} else {
853 			/* in the middle of the list */
854 			payload[h->next_hole].prev_hole = h->prev_hole;
855 			payload[h->prev_hole].next_hole = h->next_hole;
856 		}
857 
858 	} else if (h->last_byte <= start + len) {
859 		/* overlaps with final part of the hole: shorten this hole */
860 		h->last_byte = start;
861 
862 	} else if (h >= thisfrag) {
863 		/* overlaps with initial part of the hole: move this hole */
864 		newh = thisfrag + (len / 8);
865 		*newh = *h;
866 		h = newh;
867 		if (h->next_hole)
868 			payload[h->next_hole].prev_hole = (h - payload);
869 		if (h->prev_hole)
870 			payload[h->prev_hole].next_hole = (h - payload);
871 		else
872 			first_hole = (h - payload);
873 
874 	} else {
875 		/* fragment sits in the middle: split the hole */
876 		newh = thisfrag + (len / 8);
877 		*newh = *h;
878 		h->last_byte = start;
879 		h->next_hole = (newh - payload);
880 		newh->prev_hole = (h - payload);
881 		if (newh->next_hole)
882 			payload[newh->next_hole].prev_hole = (newh - payload);
883 	}
884 
885 	/* finally copy this fragment and possibly return whole packet */
886 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE_NO_UDP, len);
887 	if (!done)
888 		return NULL;
889 
890 	localip->ip_len = htons(total_len);
891 	*lenp = total_len + IP_HDR_SIZE_NO_UDP;
892 	return localip;
893 }
894 
895 static inline IP_t *NetDefragment(IP_t *ip, int *lenp)
896 {
897 	u16 ip_off = ntohs(ip->ip_off);
898 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
899 		return ip; /* not a fragment */
900 	return __NetDefragment(ip, lenp);
901 }
902 
903 #else /* !CONFIG_IP_DEFRAG */
904 
905 static inline IP_t *NetDefragment(IP_t *ip, int *lenp)
906 {
907 	u16 ip_off = ntohs(ip->ip_off);
908 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
909 		return ip; /* not a fragment */
910 	return NULL;
911 }
912 #endif
913 
914 /**
915  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
916  * drop others.
917  *
918  * @parma ip	IP packet containing the ICMP
919  */
920 static void receive_icmp(IP_t *ip, int len, IPaddr_t src_ip, Ethernet_t *et)
921 {
922 	ICMP_t *icmph = (ICMP_t *)&ip->udp_src;
923 
924 	switch (icmph->type) {
925 	case ICMP_REDIRECT:
926 		if (icmph->code != ICMP_REDIR_HOST)
927 			return;
928 		printf(" ICMP Host Redirect to %pI4 ",
929 			&icmph->un.gateway);
930 		break;
931 #if defined(CONFIG_CMD_PING)
932 	case ICMP_ECHO_REPLY:
933 		/*
934 			* IP header OK.  Pass the packet to the
935 			* current handler.
936 			*/
937 		/*
938 		 * XXX point to ip packet - should this use
939 		 * packet_icmp_handler?
940 		 */
941 		(*packetHandler)((uchar *)ip, 0, src_ip, 0, 0);
942 		break;
943 	case ICMP_ECHO_REQUEST:
944 		debug("Got ICMP ECHO REQUEST, return %d bytes\n",
945 			ETHER_HDR_SIZE + len);
946 
947 		memcpy(&et->et_dest[0], &et->et_src[0], 6);
948 		memcpy(&et->et_src[0], NetOurEther, 6);
949 
950 		ip->ip_sum = 0;
951 		ip->ip_off = 0;
952 		NetCopyIP((void *)&ip->ip_dst, &ip->ip_src);
953 		NetCopyIP((void *)&ip->ip_src, &NetOurIP);
954 		ip->ip_sum = ~NetCksum((uchar *)ip,
955 					IP_HDR_SIZE_NO_UDP >> 1);
956 
957 		icmph->type = ICMP_ECHO_REPLY;
958 		icmph->checksum = 0;
959 		icmph->checksum = ~NetCksum((uchar *)icmph,
960 			(len - IP_HDR_SIZE_NO_UDP) >> 1);
961 		(void) eth_send((uchar *)et,
962 				ETHER_HDR_SIZE + len);
963 		break;
964 #endif
965 	default:
966 #ifdef CONFIG_CMD_TFTPPUT
967 		if (packet_icmp_handler)
968 			packet_icmp_handler(icmph->type, icmph->code,
969 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
970 				icmph->un.data, ntohs(ip->udp_len));
971 #endif
972 		break;
973 	}
974 }
975 
976 void
977 NetReceive(uchar *inpkt, int len)
978 {
979 	Ethernet_t *et;
980 	IP_t	*ip;
981 #ifdef CONFIG_CMD_RARP
982 	ARP_t	*arp;
983 #endif
984 	IPaddr_t tmp;
985 	IPaddr_t src_ip;
986 	int	x;
987 #if defined(CONFIG_CMD_CDP)
988 	int iscdp;
989 #endif
990 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
991 
992 	debug("packet received\n");
993 
994 	NetRxPacket = inpkt;
995 	NetRxPacketLen = len;
996 	et = (Ethernet_t *)inpkt;
997 
998 	/* too small packet? */
999 	if (len < ETHER_HDR_SIZE)
1000 		return;
1001 
1002 #ifdef CONFIG_API
1003 	if (push_packet) {
1004 		(*push_packet)(inpkt, len);
1005 		return;
1006 	}
1007 #endif
1008 
1009 #if defined(CONFIG_CMD_CDP)
1010 	/* keep track if packet is CDP */
1011 	iscdp = is_cdp_packet(et->et_dest);
1012 #endif
1013 
1014 	myvlanid = ntohs(NetOurVLAN);
1015 	if (myvlanid == (ushort)-1)
1016 		myvlanid = VLAN_NONE;
1017 	mynvlanid = ntohs(NetOurNativeVLAN);
1018 	if (mynvlanid == (ushort)-1)
1019 		mynvlanid = VLAN_NONE;
1020 
1021 	x = ntohs(et->et_protlen);
1022 
1023 	debug("packet received\n");
1024 
1025 	if (x < 1514) {
1026 		/*
1027 		 *	Got a 802 packet.  Check the other protocol field.
1028 		 */
1029 		x = ntohs(et->et_prot);
1030 
1031 		ip = (IP_t *)(inpkt + E802_HDR_SIZE);
1032 		len -= E802_HDR_SIZE;
1033 
1034 	} else if (x != PROT_VLAN) {	/* normal packet */
1035 		ip = (IP_t *)(inpkt + ETHER_HDR_SIZE);
1036 		len -= ETHER_HDR_SIZE;
1037 
1038 	} else {			/* VLAN packet */
1039 		VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)et;
1040 
1041 		debug("VLAN packet received\n");
1042 
1043 		/* too small packet? */
1044 		if (len < VLAN_ETHER_HDR_SIZE)
1045 			return;
1046 
1047 		/* if no VLAN active */
1048 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1049 #if defined(CONFIG_CMD_CDP)
1050 				&& iscdp == 0
1051 #endif
1052 				)
1053 			return;
1054 
1055 		cti = ntohs(vet->vet_tag);
1056 		vlanid = cti & VLAN_IDMASK;
1057 		x = ntohs(vet->vet_type);
1058 
1059 		ip = (IP_t *)(inpkt + VLAN_ETHER_HDR_SIZE);
1060 		len -= VLAN_ETHER_HDR_SIZE;
1061 	}
1062 
1063 	debug("Receive from protocol 0x%x\n", x);
1064 
1065 #if defined(CONFIG_CMD_CDP)
1066 	if (iscdp) {
1067 		CDPHandler((uchar *)ip, len);
1068 		return;
1069 	}
1070 #endif
1071 
1072 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1073 		if (vlanid == VLAN_NONE)
1074 			vlanid = (mynvlanid & VLAN_IDMASK);
1075 		/* not matched? */
1076 		if (vlanid != (myvlanid & VLAN_IDMASK))
1077 			return;
1078 	}
1079 
1080 	switch (x) {
1081 
1082 	case PROT_ARP:
1083 		ArpReceive(et, ip, len);
1084 		break;
1085 
1086 #ifdef CONFIG_CMD_RARP
1087 	case PROT_RARP:
1088 		debug("Got RARP\n");
1089 		arp = (ARP_t *)ip;
1090 		if (len < ARP_HDR_SIZE) {
1091 			printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
1092 			return;
1093 		}
1094 
1095 		if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
1096 			(ntohs(arp->ar_hrd) != ARP_ETHER)   ||
1097 			(ntohs(arp->ar_pro) != PROT_IP)     ||
1098 			(arp->ar_hln != 6) || (arp->ar_pln != 4)) {
1099 
1100 			puts("invalid RARP header\n");
1101 		} else {
1102 			NetCopyIP(&NetOurIP, &arp->ar_data[16]);
1103 			if (NetServerIP == 0)
1104 				NetCopyIP(&NetServerIP, &arp->ar_data[6]);
1105 			memcpy(NetServerEther, &arp->ar_data[0], 6);
1106 
1107 			(*packetHandler)(0, 0, 0, 0, 0);
1108 		}
1109 		break;
1110 #endif
1111 	case PROT_IP:
1112 		debug("Got IP\n");
1113 		/* Before we start poking the header, make sure it is there */
1114 		if (len < IP_HDR_SIZE) {
1115 			debug("len bad %d < %lu\n", len, (ulong)IP_HDR_SIZE);
1116 			return;
1117 		}
1118 		/* Check the packet length */
1119 		if (len < ntohs(ip->ip_len)) {
1120 			printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
1121 			return;
1122 		}
1123 		len = ntohs(ip->ip_len);
1124 		debug("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
1125 
1126 		/* Can't deal with anything except IPv4 */
1127 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1128 			return;
1129 		/* Can't deal with IP options (headers != 20 bytes) */
1130 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1131 			return;
1132 		/* Check the Checksum of the header */
1133 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2)) {
1134 			puts("checksum bad\n");
1135 			return;
1136 		}
1137 		/* If it is not for us, ignore it */
1138 		tmp = NetReadIP(&ip->ip_dst);
1139 		if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) {
1140 #ifdef CONFIG_MCAST_TFTP
1141 			if (Mcast_addr != tmp)
1142 #endif
1143 				return;
1144 		}
1145 		/* Read source IP address for later use */
1146 		src_ip = NetReadIP(&ip->ip_src);
1147 		/*
1148 		 * The function returns the unchanged packet if it's not
1149 		 * a fragment, and either the complete packet or NULL if
1150 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1151 		 */
1152 		ip = NetDefragment(ip, &len);
1153 		if (!ip)
1154 			return;
1155 		/*
1156 		 * watch for ICMP host redirects
1157 		 *
1158 		 * There is no real handler code (yet). We just watch
1159 		 * for ICMP host redirect messages. In case anybody
1160 		 * sees these messages: please contact me
1161 		 * (wd@denx.de), or - even better - send me the
1162 		 * necessary fixes :-)
1163 		 *
1164 		 * Note: in all cases where I have seen this so far
1165 		 * it was a problem with the router configuration,
1166 		 * for instance when a router was configured in the
1167 		 * BOOTP reply, but the TFTP server was on the same
1168 		 * subnet. So this is probably a warning that your
1169 		 * configuration might be wrong. But I'm not really
1170 		 * sure if there aren't any other situations.
1171 		 *
1172 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1173 		 * we send a tftp packet to a dead connection, or when
1174 		 * there is no server at the other end.
1175 		 */
1176 		if (ip->ip_p == IPPROTO_ICMP) {
1177 			receive_icmp(ip, len, src_ip, et);
1178 			return;
1179 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1180 			return;
1181 		}
1182 
1183 #ifdef CONFIG_UDP_CHECKSUM
1184 		if (ip->udp_xsum != 0) {
1185 			ulong   xsum;
1186 			ushort *sumptr;
1187 			ushort  sumlen;
1188 
1189 			xsum  = ip->ip_p;
1190 			xsum += (ntohs(ip->udp_len));
1191 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1192 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1193 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1194 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1195 
1196 			sumlen = ntohs(ip->udp_len);
1197 			sumptr = (ushort *) &(ip->udp_src);
1198 
1199 			while (sumlen > 1) {
1200 				ushort sumdata;
1201 
1202 				sumdata = *sumptr++;
1203 				xsum += ntohs(sumdata);
1204 				sumlen -= 2;
1205 			}
1206 			if (sumlen > 0) {
1207 				ushort sumdata;
1208 
1209 				sumdata = *(unsigned char *) sumptr;
1210 				sumdata = (sumdata << 8) & 0xff00;
1211 				xsum += sumdata;
1212 			}
1213 			while ((xsum >> 16) != 0) {
1214 				xsum = (xsum & 0x0000ffff) +
1215 				       ((xsum >> 16) & 0x0000ffff);
1216 			}
1217 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1218 				printf(" UDP wrong checksum %08lx %08x\n",
1219 					xsum, ntohs(ip->udp_xsum));
1220 				return;
1221 			}
1222 		}
1223 #endif
1224 
1225 
1226 #ifdef CONFIG_NETCONSOLE
1227 		nc_input_packet((uchar *)ip + IP_HDR_SIZE,
1228 						ntohs(ip->udp_dst),
1229 						ntohs(ip->udp_src),
1230 						ntohs(ip->udp_len) - 8);
1231 #endif
1232 		/*
1233 		 *	IP header OK.  Pass the packet to the current handler.
1234 		 */
1235 		(*packetHandler)((uchar *)ip + IP_HDR_SIZE,
1236 						ntohs(ip->udp_dst),
1237 						src_ip,
1238 						ntohs(ip->udp_src),
1239 						ntohs(ip->udp_len) - 8);
1240 		break;
1241 	}
1242 }
1243 
1244 
1245 /**********************************************************************/
1246 
1247 static int net_check_prereq(enum proto_t protocol)
1248 {
1249 	switch (protocol) {
1250 		/* Fall through */
1251 #if defined(CONFIG_CMD_PING)
1252 	case PING:
1253 		if (NetPingIP == 0) {
1254 			puts("*** ERROR: ping address not given\n");
1255 			return 1;
1256 		}
1257 		goto common;
1258 #endif
1259 #if defined(CONFIG_CMD_SNTP)
1260 	case SNTP:
1261 		if (NetNtpServerIP == 0) {
1262 			puts("*** ERROR: NTP server address not given\n");
1263 			return 1;
1264 		}
1265 		goto common;
1266 #endif
1267 #if defined(CONFIG_CMD_DNS)
1268 	case DNS:
1269 		if (NetOurDNSIP == 0) {
1270 			puts("*** ERROR: DNS server address not given\n");
1271 			return 1;
1272 		}
1273 		goto common;
1274 #endif
1275 #if defined(CONFIG_CMD_NFS)
1276 	case NFS:
1277 #endif
1278 	case TFTPGET:
1279 	case TFTPPUT:
1280 		if (NetServerIP == 0) {
1281 			puts("*** ERROR: `serverip' not set\n");
1282 			return 1;
1283 		}
1284 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1285 	defined(CONFIG_CMD_DNS)
1286 common:
1287 #endif
1288 		/* Fall through */
1289 
1290 	case NETCONS:
1291 	case TFTPSRV:
1292 		if (NetOurIP == 0) {
1293 			puts("*** ERROR: `ipaddr' not set\n");
1294 			return 1;
1295 		}
1296 		/* Fall through */
1297 
1298 #ifdef CONFIG_CMD_RARP
1299 	case RARP:
1300 #endif
1301 	case BOOTP:
1302 	case CDP:
1303 	case DHCP:
1304 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1305 			int num = eth_get_dev_index();
1306 
1307 			switch (num) {
1308 			case -1:
1309 				puts("*** ERROR: No ethernet found.\n");
1310 				return 1;
1311 			case 0:
1312 				puts("*** ERROR: `ethaddr' not set\n");
1313 				break;
1314 			default:
1315 				printf("*** ERROR: `eth%daddr' not set\n",
1316 					num);
1317 				break;
1318 			}
1319 
1320 			NetStartAgain();
1321 			return 2;
1322 		}
1323 		/* Fall through */
1324 	default:
1325 		return 0;
1326 	}
1327 	return 0;		/* OK */
1328 }
1329 /**********************************************************************/
1330 
1331 int
1332 NetCksumOk(uchar *ptr, int len)
1333 {
1334 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1335 }
1336 
1337 
1338 unsigned
1339 NetCksum(uchar *ptr, int len)
1340 {
1341 	ulong	xsum;
1342 	ushort *p = (ushort *)ptr;
1343 
1344 	xsum = 0;
1345 	while (len-- > 0)
1346 		xsum += *p++;
1347 	xsum = (xsum & 0xffff) + (xsum >> 16);
1348 	xsum = (xsum & 0xffff) + (xsum >> 16);
1349 	return xsum & 0xffff;
1350 }
1351 
1352 int
1353 NetEthHdrSize(void)
1354 {
1355 	ushort myvlanid;
1356 
1357 	myvlanid = ntohs(NetOurVLAN);
1358 	if (myvlanid == (ushort)-1)
1359 		myvlanid = VLAN_NONE;
1360 
1361 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1362 		VLAN_ETHER_HDR_SIZE;
1363 }
1364 
1365 int
1366 NetSetEther(uchar *xet, uchar * addr, uint prot)
1367 {
1368 	Ethernet_t *et = (Ethernet_t *)xet;
1369 	ushort myvlanid;
1370 
1371 	myvlanid = ntohs(NetOurVLAN);
1372 	if (myvlanid == (ushort)-1)
1373 		myvlanid = VLAN_NONE;
1374 
1375 	memcpy(et->et_dest, addr, 6);
1376 	memcpy(et->et_src, NetOurEther, 6);
1377 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1378 		et->et_protlen = htons(prot);
1379 		return ETHER_HDR_SIZE;
1380 	} else {
1381 		VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)xet;
1382 
1383 		vet->vet_vlan_type = htons(PROT_VLAN);
1384 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1385 		vet->vet_type = htons(prot);
1386 		return VLAN_ETHER_HDR_SIZE;
1387 	}
1388 }
1389 
1390 void
1391 NetSetIP(uchar *xip, IPaddr_t dest, int dport, int sport, int len)
1392 {
1393 	IP_t *ip = (IP_t *)xip;
1394 
1395 	/*
1396 	 *	If the data is an odd number of bytes, zero the
1397 	 *	byte after the last byte so that the checksum
1398 	 *	will work.
1399 	 */
1400 	if (len & 1)
1401 		xip[IP_HDR_SIZE + len] = 0;
1402 
1403 	/*
1404 	 *	Construct an IP and UDP header.
1405 	 *	(need to set no fragment bit - XXX)
1406 	 */
1407 	/* IP_HDR_SIZE / 4 (not including UDP) */
1408 	ip->ip_hl_v  = 0x45;
1409 	ip->ip_tos   = 0;
1410 	ip->ip_len   = htons(IP_HDR_SIZE + len);
1411 	ip->ip_id    = htons(NetIPID++);
1412 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1413 	ip->ip_ttl   = 255;
1414 	ip->ip_p     = 17;		/* UDP */
1415 	ip->ip_sum   = 0;
1416 	/* already in network byte order */
1417 	NetCopyIP((void *)&ip->ip_src, &NetOurIP);
1418 	/* - "" - */
1419 	NetCopyIP((void *)&ip->ip_dst, &dest);
1420 	ip->udp_src  = htons(sport);
1421 	ip->udp_dst  = htons(dport);
1422 	ip->udp_len  = htons(8 + len);
1423 	ip->udp_xsum = 0;
1424 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
1425 }
1426 
1427 void copy_filename(char *dst, const char *src, int size)
1428 {
1429 	if (*src && (*src == '"')) {
1430 		++src;
1431 		--size;
1432 	}
1433 
1434 	while ((--size > 0) && *src && (*src != '"'))
1435 		*dst++ = *src++;
1436 	*dst = '\0';
1437 }
1438 
1439 #if	defined(CONFIG_CMD_NFS)		|| \
1440 	defined(CONFIG_CMD_SNTP)	|| \
1441 	defined(CONFIG_CMD_DNS)
1442 /*
1443  * make port a little random (1024-17407)
1444  * This keeps the math somewhat trivial to compute, and seems to work with
1445  * all supported protocols/clients/servers
1446  */
1447 unsigned int random_port(void)
1448 {
1449 	return 1024 + (get_timer(0) % 0x4000);
1450 }
1451 #endif
1452 
1453 void ip_to_string(IPaddr_t x, char *s)
1454 {
1455 	x = ntohl(x);
1456 	sprintf(s, "%d.%d.%d.%d",
1457 		(int) ((x >> 24) & 0xff),
1458 		(int) ((x >> 16) & 0xff),
1459 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1460 	);
1461 }
1462 
1463 void VLAN_to_string(ushort x, char *s)
1464 {
1465 	x = ntohs(x);
1466 
1467 	if (x == (ushort)-1)
1468 		x = VLAN_NONE;
1469 
1470 	if (x == VLAN_NONE)
1471 		strcpy(s, "none");
1472 	else
1473 		sprintf(s, "%d", x & VLAN_IDMASK);
1474 }
1475 
1476 ushort string_to_VLAN(const char *s)
1477 {
1478 	ushort id;
1479 
1480 	if (s == NULL)
1481 		return htons(VLAN_NONE);
1482 
1483 	if (*s < '0' || *s > '9')
1484 		id = VLAN_NONE;
1485 	else
1486 		id = (ushort)simple_strtoul(s, NULL, 10);
1487 
1488 	return htons(id);
1489 }
1490 
1491 ushort getenv_VLAN(char *var)
1492 {
1493 	return string_to_VLAN(getenv(var));
1494 }
1495