xref: /openbmc/u-boot/net/net.c (revision ae03661f)
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 <net.h>
81 #include "bootp.h"
82 #include "tftp.h"
83 #ifdef CONFIG_CMD_RARP
84 #include "rarp.h"
85 #endif
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 #if defined(CONFIG_CDP_VERSION)
95 #include <timestamp.h>
96 #endif
97 #if defined(CONFIG_CMD_DNS)
98 #include "dns.h"
99 #endif
100 
101 DECLARE_GLOBAL_DATA_PTR;
102 
103 #ifndef	CONFIG_ARP_TIMEOUT
104 /* Milliseconds before trying ARP again */
105 # define ARP_TIMEOUT		5000UL
106 #else
107 # define ARP_TIMEOUT		CONFIG_ARP_TIMEOUT
108 #endif
109 
110 
111 #ifndef	CONFIG_NET_RETRY_COUNT
112 # define ARP_TIMEOUT_COUNT	5	/* # of timeouts before giving up  */
113 #else
114 # define ARP_TIMEOUT_COUNT	CONFIG_NET_RETRY_COUNT
115 #endif
116 
117 /** BOOTP EXTENTIONS **/
118 
119 /* Our subnet mask (0=unknown) */
120 IPaddr_t	NetOurSubnetMask;
121 /* Our gateways IP address */
122 IPaddr_t	NetOurGatewayIP;
123 /* Our DNS IP address */
124 IPaddr_t	NetOurDNSIP;
125 #if defined(CONFIG_BOOTP_DNS2)
126 /* Our 2nd DNS IP address */
127 IPaddr_t	NetOurDNS2IP;
128 #endif
129 /* Our NIS domain */
130 char		NetOurNISDomain[32] = {0,};
131 /* Our hostname */
132 char		NetOurHostName[32] = {0,};
133 /* Our bootpath */
134 char		NetOurRootPath[64] = {0,};
135 /* Our bootfile size in blocks */
136 ushort		NetBootFileSize;
137 
138 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
139 IPaddr_t Mcast_addr;
140 #endif
141 
142 /** END OF BOOTP EXTENTIONS **/
143 
144 /* The actual transferred size of the bootfile (in bytes) */
145 ulong		NetBootFileXferSize;
146 /* Our ethernet address */
147 uchar		NetOurEther[6];
148 /* Boot server enet address */
149 uchar		NetServerEther[6];
150 /* Our IP addr (0 = unknown) */
151 IPaddr_t	NetOurIP;
152 /* Server IP addr (0 = unknown) */
153 IPaddr_t	NetServerIP;
154 /* Current receive packet */
155 volatile uchar *NetRxPacket;
156 /* Current rx packet length */
157 int		NetRxPacketLen;
158 /* IP packet ID */
159 unsigned	NetIPID;
160 /* Ethernet bcast address */
161 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
162 uchar		NetEtherNullAddr[6];
163 #ifdef CONFIG_API
164 void		(*push_packet)(volatile void *, int len) = 0;
165 #endif
166 #if defined(CONFIG_CMD_CDP)
167 /* Ethernet bcast address */
168 uchar		NetCDPAddr[6] = { 0x01, 0x00, 0x0c, 0xcc, 0xcc, 0xcc };
169 #endif
170 /* Network loop state */
171 int		NetState;
172 /* Tried all network devices */
173 int		NetRestartWrap;
174 /* Network loop restarted */
175 static int	NetRestarted;
176 /* At least one device configured */
177 static int	NetDevExists;
178 
179 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
180 /* default is without VLAN */
181 ushort		NetOurVLAN = 0xFFFF;
182 /* ditto */
183 ushort		NetOurNativeVLAN = 0xFFFF;
184 
185 /* Boot File name */
186 char		BootFile[128];
187 
188 #if defined(CONFIG_CMD_PING)
189 /* the ip address to ping */
190 IPaddr_t	NetPingIP;
191 
192 static void PingStart(void);
193 #endif
194 
195 #if defined(CONFIG_CMD_CDP)
196 static void CDPStart(void);
197 #endif
198 
199 #if defined(CONFIG_CMD_SNTP)
200 /* NTP server IP address */
201 IPaddr_t	NetNtpServerIP;
202 /* offset time from UTC */
203 int		NetTimeOffset;
204 #endif
205 
206 #ifdef CONFIG_NETCONSOLE
207 void NcStart(void);
208 int nc_input_packet(uchar *pkt, unsigned dest, unsigned src, unsigned len);
209 #endif
210 
211 volatile uchar	PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
212 
213 /* Receive packet */
214 volatile uchar *NetRxPackets[PKTBUFSRX];
215 
216 /* Current RX packet handler */
217 static rxhand_f *packetHandler;
218 #ifdef CONFIG_CMD_TFTPPUT
219 static rxhand_icmp_f *packet_icmp_handler;	/* Current ICMP rx handler */
220 #endif
221 /* Current timeout handler */
222 static thand_f *timeHandler;
223 /* Time base value */
224 static ulong	timeStart;
225 /* Current timeout value */
226 static ulong	timeDelta;
227 /* THE transmit packet */
228 volatile uchar *NetTxPacket;
229 
230 static int net_check_prereq(enum proto_t protocol);
231 
232 static int NetTryCount;
233 
234 /**********************************************************************/
235 
236 IPaddr_t	NetArpWaitPacketIP;
237 IPaddr_t	NetArpWaitReplyIP;
238 /* MAC address of waiting packet's destination */
239 uchar	       *NetArpWaitPacketMAC;
240 /* THE transmit packet */
241 uchar	       *NetArpWaitTxPacket;
242 int		NetArpWaitTxPacketSize;
243 uchar		NetArpWaitPacketBuf[PKTSIZE_ALIGN + PKTALIGN];
244 ulong		NetArpWaitTimerStart;
245 int		NetArpWaitTry;
246 
247 void ArpRequest(void)
248 {
249 	volatile uchar *pkt;
250 	ARP_t *arp;
251 
252 	debug("ARP broadcast %d\n", NetArpWaitTry);
253 
254 	pkt = NetTxPacket;
255 
256 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_ARP);
257 
258 	arp = (ARP_t *) pkt;
259 
260 	arp->ar_hrd = htons(ARP_ETHER);
261 	arp->ar_pro = htons(PROT_IP);
262 	arp->ar_hln = 6;
263 	arp->ar_pln = 4;
264 	arp->ar_op = htons(ARPOP_REQUEST);
265 
266 	/* source ET addr */
267 	memcpy(&arp->ar_data[0], NetOurEther, 6);
268 	/* source IP addr */
269 	NetWriteIP((uchar *) &arp->ar_data[6], NetOurIP);
270 	/* dest ET addr = 0 */
271 	memset(&arp->ar_data[10], '\0', 6);
272 	if ((NetArpWaitPacketIP & NetOurSubnetMask) !=
273 	    (NetOurIP & NetOurSubnetMask)) {
274 		if (NetOurGatewayIP == 0) {
275 			puts("## Warning: gatewayip needed but not set\n");
276 			NetArpWaitReplyIP = NetArpWaitPacketIP;
277 		} else {
278 			NetArpWaitReplyIP = NetOurGatewayIP;
279 		}
280 	} else {
281 		NetArpWaitReplyIP = NetArpWaitPacketIP;
282 	}
283 
284 	NetWriteIP((uchar *) &arp->ar_data[16], NetArpWaitReplyIP);
285 	(void) eth_send(NetTxPacket, (pkt - NetTxPacket) + ARP_HDR_SIZE);
286 }
287 
288 void ArpTimeoutCheck(void)
289 {
290 	ulong t;
291 
292 	if (!NetArpWaitPacketIP)
293 		return;
294 
295 	t = get_timer(0);
296 
297 	/* check for arp timeout */
298 	if ((t - NetArpWaitTimerStart) > ARP_TIMEOUT) {
299 		NetArpWaitTry++;
300 
301 		if (NetArpWaitTry >= ARP_TIMEOUT_COUNT) {
302 			puts("\nARP Retry count exceeded; starting again\n");
303 			NetArpWaitTry = 0;
304 			NetStartAgain();
305 		} else {
306 			NetArpWaitTimerStart = t;
307 			ArpRequest();
308 		}
309 	}
310 }
311 
312 /*
313  * Check if autoload is enabled. If so, use either NFS or TFTP to download
314  * the boot file.
315  */
316 void net_auto_load(void)
317 {
318 	const char *s = getenv("autoload");
319 
320 	if (s != NULL) {
321 		if (*s == 'n') {
322 			/*
323 			 * Just use BOOTP/RARP to configure system;
324 			 * Do not use TFTP to load the bootfile.
325 			 */
326 			NetState = NETLOOP_SUCCESS;
327 			return;
328 		}
329 #if defined(CONFIG_CMD_NFS)
330 		if (strcmp(s, "NFS") == 0) {
331 			/*
332 			 * Use NFS to load the bootfile.
333 			 */
334 			NfsStart();
335 			return;
336 		}
337 #endif
338 	}
339 	TftpStart(TFTPGET);
340 }
341 
342 static void NetInitLoop(enum proto_t protocol)
343 {
344 	static int env_changed_id;
345 	bd_t *bd = gd->bd;
346 	int env_id = get_env_id();
347 
348 	/* update only when the environment has changed */
349 	if (env_changed_id != env_id) {
350 		NetOurIP = getenv_IPaddr("ipaddr");
351 		NetCopyIP(&bd->bi_ip_addr, &NetOurIP);
352 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
353 		NetOurSubnetMask = getenv_IPaddr("netmask");
354 		NetServerIP = getenv_IPaddr("serverip");
355 		NetOurNativeVLAN = getenv_VLAN("nvlan");
356 		NetOurVLAN = getenv_VLAN("vlan");
357 #if defined(CONFIG_CMD_DNS)
358 		NetOurDNSIP = getenv_IPaddr("dnsip");
359 #endif
360 		env_changed_id = env_id;
361 	}
362 
363 	return;
364 }
365 
366 /**********************************************************************/
367 /*
368  *	Main network processing loop.
369  */
370 
371 int NetLoop(enum proto_t protocol)
372 {
373 	bd_t *bd = gd->bd;
374 	int ret = -1;
375 
376 	NetRestarted = 0;
377 	NetDevExists = 0;
378 
379 	/* XXX problem with bss workaround */
380 	NetArpWaitPacketMAC = NULL;
381 	NetArpWaitTxPacket = NULL;
382 	NetArpWaitPacketIP = 0;
383 	NetArpWaitReplyIP = 0;
384 	NetArpWaitTxPacket = NULL;
385 	NetTxPacket = NULL;
386 	NetTryCount = 1;
387 
388 	if (!NetTxPacket) {
389 		int	i;
390 		/*
391 		 *	Setup packet buffers, aligned correctly.
392 		 */
393 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
394 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
395 		for (i = 0; i < PKTBUFSRX; i++)
396 			NetRxPackets[i] = NetTxPacket + (i+1)*PKTSIZE_ALIGN;
397 	}
398 
399 	if (!NetArpWaitTxPacket) {
400 		NetArpWaitTxPacket = &NetArpWaitPacketBuf[0] + (PKTALIGN - 1);
401 		NetArpWaitTxPacket -= (ulong)NetArpWaitTxPacket % PKTALIGN;
402 		NetArpWaitTxPacketSize = 0;
403 	}
404 
405 	eth_halt();
406 	eth_set_current();
407 	if (eth_init(bd) < 0) {
408 		eth_halt();
409 		return -1;
410 	}
411 
412 restart:
413 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
414 
415 	NetState = NETLOOP_CONTINUE;
416 
417 	/*
418 	 *	Start the ball rolling with the given start function.  From
419 	 *	here on, this code is a state machine driven by received
420 	 *	packets and timer events.
421 	 */
422 	NetInitLoop(protocol);
423 
424 	switch (net_check_prereq(protocol)) {
425 	case 1:
426 		/* network not configured */
427 		eth_halt();
428 		return -1;
429 
430 	case 2:
431 		/* network device not configured */
432 		break;
433 
434 	case 0:
435 		NetDevExists = 1;
436 		NetBootFileXferSize = 0;
437 		switch (protocol) {
438 		case TFTPGET:
439 #ifdef CONFIG_CMD_TFTPPUT
440 		case TFTPPUT:
441 #endif
442 			/* always use ARP to get server ethernet address */
443 			TftpStart(protocol);
444 			break;
445 #ifdef CONFIG_CMD_TFTPSRV
446 		case TFTPSRV:
447 			TftpStartServer();
448 			break;
449 #endif
450 #if defined(CONFIG_CMD_DHCP)
451 		case DHCP:
452 			BootpTry = 0;
453 			NetOurIP = 0;
454 			DhcpRequest();		/* Basically same as BOOTP */
455 			break;
456 #endif
457 
458 		case BOOTP:
459 			BootpTry = 0;
460 			NetOurIP = 0;
461 			BootpRequest();
462 			break;
463 
464 #if defined(CONFIG_CMD_RARP)
465 		case RARP:
466 			RarpTry = 0;
467 			NetOurIP = 0;
468 			RarpRequest();
469 			break;
470 #endif
471 #if defined(CONFIG_CMD_PING)
472 		case PING:
473 			PingStart();
474 			break;
475 #endif
476 #if defined(CONFIG_CMD_NFS)
477 		case NFS:
478 			NfsStart();
479 			break;
480 #endif
481 #if defined(CONFIG_CMD_CDP)
482 		case CDP:
483 			CDPStart();
484 			break;
485 #endif
486 #ifdef CONFIG_NETCONSOLE
487 		case NETCONS:
488 			NcStart();
489 			break;
490 #endif
491 #if defined(CONFIG_CMD_SNTP)
492 		case SNTP:
493 			SntpStart();
494 			break;
495 #endif
496 #if defined(CONFIG_CMD_DNS)
497 		case DNS:
498 			DnsStart();
499 			break;
500 #endif
501 		default:
502 			break;
503 		}
504 
505 		break;
506 	}
507 
508 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
509 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
510 	defined(CONFIG_STATUS_LED)			&& \
511 	defined(STATUS_LED_RED)
512 	/*
513 	 * Echo the inverted link state to the fault LED.
514 	 */
515 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
516 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
517 	else
518 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
519 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
520 #endif /* CONFIG_MII, ... */
521 
522 	/*
523 	 *	Main packet reception loop.  Loop receiving packets until
524 	 *	someone sets `NetState' to a state that terminates.
525 	 */
526 	for (;;) {
527 		WATCHDOG_RESET();
528 #ifdef CONFIG_SHOW_ACTIVITY
529 		{
530 			extern void show_activity(int arg);
531 			show_activity(1);
532 		}
533 #endif
534 		/*
535 		 *	Check the ethernet for a new packet.  The ethernet
536 		 *	receive routine will process it.
537 		 */
538 		eth_rx();
539 
540 		/*
541 		 *	Abort if ctrl-c was pressed.
542 		 */
543 		if (ctrlc()) {
544 			eth_halt();
545 			puts("\nAbort\n");
546 			goto done;
547 		}
548 
549 		ArpTimeoutCheck();
550 
551 		/*
552 		 *	Check for a timeout, and run the timeout handler
553 		 *	if we have one.
554 		 */
555 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
556 			thand_f *x;
557 
558 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
559 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
560 	defined(CONFIG_STATUS_LED)			&& \
561 	defined(STATUS_LED_RED)
562 			/*
563 			 * Echo the inverted link state to the fault LED.
564 			 */
565 			if (miiphy_link(eth_get_dev()->name,
566 				       CONFIG_SYS_FAULT_MII_ADDR)) {
567 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
568 			} else {
569 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
570 			}
571 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
572 #endif /* CONFIG_MII, ... */
573 			x = timeHandler;
574 			timeHandler = (thand_f *)0;
575 			(*x)();
576 		}
577 
578 
579 		switch (NetState) {
580 
581 		case NETLOOP_RESTART:
582 			NetRestarted = 1;
583 			goto restart;
584 
585 		case NETLOOP_SUCCESS:
586 			if (NetBootFileXferSize > 0) {
587 				char buf[20];
588 				printf("Bytes transferred = %ld (%lx hex)\n",
589 					NetBootFileXferSize,
590 					NetBootFileXferSize);
591 				sprintf(buf, "%lX", NetBootFileXferSize);
592 				setenv("filesize", buf);
593 
594 				sprintf(buf, "%lX", (unsigned long)load_addr);
595 				setenv("fileaddr", buf);
596 			}
597 			eth_halt();
598 			ret = NetBootFileXferSize;
599 			goto done;
600 
601 		case NETLOOP_FAIL:
602 			goto done;
603 		}
604 	}
605 
606 done:
607 #ifdef CONFIG_CMD_TFTPPUT
608 	/* Clear out the handlers */
609 	NetSetHandler(NULL);
610 	net_set_icmp_handler(NULL);
611 #endif
612 	return ret;
613 }
614 
615 /**********************************************************************/
616 
617 static void
618 startAgainTimeout(void)
619 {
620 	NetState = NETLOOP_RESTART;
621 }
622 
623 static void
624 startAgainHandler(uchar *pkt, unsigned dest, IPaddr_t sip,
625 		  unsigned src, unsigned len)
626 {
627 	/* Totally ignore the packet */
628 }
629 
630 void NetStartAgain(void)
631 {
632 	char *nretry;
633 	int retry_forever = 0;
634 	unsigned long retrycnt = 0;
635 
636 	nretry = getenv("netretry");
637 	if (nretry) {
638 		if (!strcmp(nretry, "yes"))
639 			retry_forever = 1;
640 		else if (!strcmp(nretry, "no"))
641 			retrycnt = 0;
642 		else if (!strcmp(nretry, "once"))
643 			retrycnt = 1;
644 		else
645 			retrycnt = simple_strtoul(nretry, NULL, 0);
646 	} else
647 		retry_forever = 1;
648 
649 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
650 		eth_halt();
651 		NetState = NETLOOP_FAIL;
652 		return;
653 	}
654 
655 	NetTryCount++;
656 
657 	eth_halt();
658 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
659 	eth_try_another(!NetRestarted);
660 #endif
661 	eth_init(gd->bd);
662 	if (NetRestartWrap) {
663 		NetRestartWrap = 0;
664 		if (NetDevExists) {
665 			NetSetTimeout(10000UL, startAgainTimeout);
666 			NetSetHandler(startAgainHandler);
667 		} else {
668 			NetState = NETLOOP_FAIL;
669 		}
670 	} else {
671 		NetState = NETLOOP_RESTART;
672 	}
673 }
674 
675 /**********************************************************************/
676 /*
677  *	Miscelaneous bits.
678  */
679 
680 void
681 NetSetHandler(rxhand_f *f)
682 {
683 	packetHandler = f;
684 }
685 
686 #ifdef CONFIG_CMD_TFTPPUT
687 void net_set_icmp_handler(rxhand_icmp_f *f)
688 {
689 	packet_icmp_handler = f;
690 }
691 #endif
692 
693 void
694 NetSetTimeout(ulong iv, thand_f *f)
695 {
696 	if (iv == 0) {
697 		timeHandler = (thand_f *)0;
698 	} else {
699 		timeHandler = f;
700 		timeStart = get_timer(0);
701 		timeDelta = iv;
702 	}
703 }
704 
705 
706 void
707 NetSendPacket(volatile uchar *pkt, int len)
708 {
709 	(void) eth_send(pkt, len);
710 }
711 
712 int
713 NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport, int len)
714 {
715 	uchar *pkt;
716 
717 	/* convert to new style broadcast */
718 	if (dest == 0)
719 		dest = 0xFFFFFFFF;
720 
721 	/* if broadcast, make the ether address a broadcast and don't do ARP */
722 	if (dest == 0xFFFFFFFF)
723 		ether = NetBcastAddr;
724 
725 	/*
726 	 * if MAC address was not discovered yet, save the packet and do
727 	 * an ARP request
728 	 */
729 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
730 
731 		debug("sending ARP for %08x\n", dest);
732 
733 		NetArpWaitPacketIP = dest;
734 		NetArpWaitPacketMAC = ether;
735 
736 		pkt = NetArpWaitTxPacket;
737 		pkt += NetSetEther(pkt, NetArpWaitPacketMAC, PROT_IP);
738 
739 		NetSetIP(pkt, dest, dport, sport, len);
740 		memcpy(pkt + IP_HDR_SIZE, (uchar *)NetTxPacket +
741 		       (pkt - (uchar *)NetArpWaitTxPacket) + IP_HDR_SIZE, len);
742 
743 		/* size of the waiting packet */
744 		NetArpWaitTxPacketSize = (pkt - NetArpWaitTxPacket) +
745 			IP_HDR_SIZE + len;
746 
747 		/* and do the ARP request */
748 		NetArpWaitTry = 1;
749 		NetArpWaitTimerStart = get_timer(0);
750 		ArpRequest();
751 		return 1;	/* waiting */
752 	}
753 
754 	debug("sending UDP to %08x/%pM\n", dest, ether);
755 
756 	pkt = (uchar *)NetTxPacket;
757 	pkt += NetSetEther(pkt, ether, PROT_IP);
758 	NetSetIP(pkt, dest, dport, sport, len);
759 	(void) eth_send(NetTxPacket, (pkt - NetTxPacket) + IP_HDR_SIZE + len);
760 
761 	return 0;	/* transmitted */
762 }
763 
764 #if defined(CONFIG_CMD_PING)
765 static ushort PingSeqNo;
766 
767 int PingSend(void)
768 {
769 	static uchar mac[6];
770 	volatile IP_t *ip;
771 	volatile ushort *s;
772 	uchar *pkt;
773 
774 	/* XXX always send arp request */
775 
776 	memcpy(mac, NetEtherNullAddr, 6);
777 
778 	debug("sending ARP for %08x\n", NetPingIP);
779 
780 	NetArpWaitPacketIP = NetPingIP;
781 	NetArpWaitPacketMAC = mac;
782 
783 	pkt = NetArpWaitTxPacket;
784 	pkt += NetSetEther(pkt, mac, PROT_IP);
785 
786 	ip = (volatile IP_t *)pkt;
787 
788 	/*
789 	 * Construct an IP and ICMP header.
790 	 * (need to set no fragment bit - XXX)
791 	 */
792 	/* IP_HDR_SIZE / 4 (not including UDP) */
793 	ip->ip_hl_v  = 0x45;
794 	ip->ip_tos   = 0;
795 	ip->ip_len   = htons(IP_HDR_SIZE_NO_UDP + 8);
796 	ip->ip_id    = htons(NetIPID++);
797 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
798 	ip->ip_ttl   = 255;
799 	ip->ip_p     = 0x01;		/* ICMP */
800 	ip->ip_sum   = 0;
801 	/* already in network byte order */
802 	NetCopyIP((void *)&ip->ip_src, &NetOurIP);
803 	/* - "" - */
804 	NetCopyIP((void *)&ip->ip_dst, &NetPingIP);
805 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
806 
807 	s = &ip->udp_src;		/* XXX ICMP starts here */
808 	s[0] = htons(0x0800);		/* echo-request, code */
809 	s[1] = 0;			/* checksum */
810 	s[2] = 0;			/* identifier */
811 	s[3] = htons(PingSeqNo++);	/* sequence number */
812 	s[1] = ~NetCksum((uchar *)s, 8/2);
813 
814 	/* size of the waiting packet */
815 	NetArpWaitTxPacketSize =
816 		(pkt - NetArpWaitTxPacket) + IP_HDR_SIZE_NO_UDP + 8;
817 
818 	/* and do the ARP request */
819 	NetArpWaitTry = 1;
820 	NetArpWaitTimerStart = get_timer(0);
821 	ArpRequest();
822 	return 1;	/* waiting */
823 }
824 
825 static void
826 PingTimeout(void)
827 {
828 	eth_halt();
829 	NetState = NETLOOP_FAIL;	/* we did not get the reply */
830 }
831 
832 static void
833 PingHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
834 	    unsigned len)
835 {
836 	if (sip != NetPingIP)
837 		return;
838 
839 	NetState = NETLOOP_SUCCESS;
840 }
841 
842 static void PingStart(void)
843 {
844 	printf("Using %s device\n", eth_get_name());
845 	NetSetTimeout(10000UL, PingTimeout);
846 	NetSetHandler(PingHandler);
847 
848 	PingSend();
849 }
850 #endif
851 
852 #if defined(CONFIG_CMD_CDP)
853 
854 #define CDP_DEVICE_ID_TLV		0x0001
855 #define CDP_ADDRESS_TLV			0x0002
856 #define CDP_PORT_ID_TLV			0x0003
857 #define CDP_CAPABILITIES_TLV		0x0004
858 #define CDP_VERSION_TLV			0x0005
859 #define CDP_PLATFORM_TLV		0x0006
860 #define CDP_NATIVE_VLAN_TLV		0x000a
861 #define CDP_APPLIANCE_VLAN_TLV		0x000e
862 #define CDP_TRIGGER_TLV			0x000f
863 #define CDP_POWER_CONSUMPTION_TLV	0x0010
864 #define CDP_SYSNAME_TLV			0x0014
865 #define CDP_SYSOBJECT_TLV		0x0015
866 #define CDP_MANAGEMENT_ADDRESS_TLV	0x0016
867 
868 #define CDP_TIMEOUT			250UL	/* one packet every 250ms */
869 
870 static int CDPSeq;
871 static int CDPOK;
872 
873 ushort CDPNativeVLAN;
874 ushort CDPApplianceVLAN;
875 
876 static const uchar CDP_SNAP_hdr[8] = { 0xAA, 0xAA, 0x03, 0x00, 0x00, 0x0C, 0x20,
877 				       0x00 };
878 
879 static ushort CDP_compute_csum(const uchar *buff, ushort len)
880 {
881 	ushort csum;
882 	int     odd;
883 	ulong   result = 0;
884 	ushort  leftover;
885 	ushort *p;
886 
887 	if (len > 0) {
888 		odd = 1 & (ulong)buff;
889 		if (odd) {
890 			result = *buff << 8;
891 			len--;
892 			buff++;
893 		}
894 		while (len > 1) {
895 			p = (ushort *)buff;
896 			result += *p++;
897 			buff = (uchar *)p;
898 			if (result & 0x80000000)
899 				result = (result & 0xFFFF) + (result >> 16);
900 			len -= 2;
901 		}
902 		if (len) {
903 			leftover = (signed short)(*(const signed char *)buff);
904 			/* CISCO SUCKS big time! (and blows too):
905 			 * CDP uses the IP checksum algorithm with a twist;
906 			 * for the last byte it *sign* extends and sums.
907 			 */
908 			result = (result & 0xffff0000) |
909 				 ((result + leftover) & 0x0000ffff);
910 		}
911 		while (result >> 16)
912 			result = (result & 0xFFFF) + (result >> 16);
913 
914 		if (odd)
915 			result = ((result >> 8) & 0xff) |
916 				 ((result & 0xff) << 8);
917 	}
918 
919 	/* add up 16-bit and 17-bit words for 17+c bits */
920 	result = (result & 0xffff) + (result >> 16);
921 	/* add up 16-bit and 2-bit for 16+c bit */
922 	result = (result & 0xffff) + (result >> 16);
923 	/* add up carry.. */
924 	result = (result & 0xffff) + (result >> 16);
925 
926 	/* negate */
927 	csum = ~(ushort)result;
928 
929 	/* run time endian detection */
930 	if (csum != htons(csum))	/* little endian */
931 		csum = htons(csum);
932 
933 	return csum;
934 }
935 
936 int CDPSendTrigger(void)
937 {
938 	volatile uchar *pkt;
939 	volatile ushort *s;
940 	volatile ushort *cp;
941 	Ethernet_t *et;
942 	int len;
943 	ushort chksum;
944 #if	defined(CONFIG_CDP_DEVICE_ID) || defined(CONFIG_CDP_PORT_ID)   || \
945 	defined(CONFIG_CDP_VERSION)   || defined(CONFIG_CDP_PLATFORM)
946 	char buf[32];
947 #endif
948 
949 	pkt = NetTxPacket;
950 	et = (Ethernet_t *)pkt;
951 
952 	/* NOTE: trigger sent not on any VLAN */
953 
954 	/* form ethernet header */
955 	memcpy(et->et_dest, NetCDPAddr, 6);
956 	memcpy(et->et_src, NetOurEther, 6);
957 
958 	pkt += ETHER_HDR_SIZE;
959 
960 	/* SNAP header */
961 	memcpy((uchar *)pkt, CDP_SNAP_hdr, sizeof(CDP_SNAP_hdr));
962 	pkt += sizeof(CDP_SNAP_hdr);
963 
964 	/* CDP header */
965 	*pkt++ = 0x02;				/* CDP version 2 */
966 	*pkt++ = 180;				/* TTL */
967 	s = (volatile ushort *)pkt;
968 	cp = s;
969 	/* checksum (0 for later calculation) */
970 	*s++ = htons(0);
971 
972 	/* CDP fields */
973 #ifdef CONFIG_CDP_DEVICE_ID
974 	*s++ = htons(CDP_DEVICE_ID_TLV);
975 	*s++ = htons(CONFIG_CDP_DEVICE_ID);
976 	sprintf(buf, CONFIG_CDP_DEVICE_ID_PREFIX "%pm", NetOurEther);
977 	memcpy((uchar *)s, buf, 16);
978 	s += 16 / 2;
979 #endif
980 
981 #ifdef CONFIG_CDP_PORT_ID
982 	*s++ = htons(CDP_PORT_ID_TLV);
983 	memset(buf, 0, sizeof(buf));
984 	sprintf(buf, CONFIG_CDP_PORT_ID, eth_get_dev_index());
985 	len = strlen(buf);
986 	if (len & 1)	/* make it even */
987 		len++;
988 	*s++ = htons(len + 4);
989 	memcpy((uchar *)s, buf, len);
990 	s += len / 2;
991 #endif
992 
993 #ifdef CONFIG_CDP_CAPABILITIES
994 	*s++ = htons(CDP_CAPABILITIES_TLV);
995 	*s++ = htons(8);
996 	*(ulong *)s = htonl(CONFIG_CDP_CAPABILITIES);
997 	s += 2;
998 #endif
999 
1000 #ifdef CONFIG_CDP_VERSION
1001 	*s++ = htons(CDP_VERSION_TLV);
1002 	memset(buf, 0, sizeof(buf));
1003 	strcpy(buf, CONFIG_CDP_VERSION);
1004 	len = strlen(buf);
1005 	if (len & 1)	/* make it even */
1006 		len++;
1007 	*s++ = htons(len + 4);
1008 	memcpy((uchar *)s, buf, len);
1009 	s += len / 2;
1010 #endif
1011 
1012 #ifdef CONFIG_CDP_PLATFORM
1013 	*s++ = htons(CDP_PLATFORM_TLV);
1014 	memset(buf, 0, sizeof(buf));
1015 	strcpy(buf, CONFIG_CDP_PLATFORM);
1016 	len = strlen(buf);
1017 	if (len & 1)	/* make it even */
1018 		len++;
1019 	*s++ = htons(len + 4);
1020 	memcpy((uchar *)s, buf, len);
1021 	s += len / 2;
1022 #endif
1023 
1024 #ifdef CONFIG_CDP_TRIGGER
1025 	*s++ = htons(CDP_TRIGGER_TLV);
1026 	*s++ = htons(8);
1027 	*(ulong *)s = htonl(CONFIG_CDP_TRIGGER);
1028 	s += 2;
1029 #endif
1030 
1031 #ifdef CONFIG_CDP_POWER_CONSUMPTION
1032 	*s++ = htons(CDP_POWER_CONSUMPTION_TLV);
1033 	*s++ = htons(6);
1034 	*s++ = htons(CONFIG_CDP_POWER_CONSUMPTION);
1035 #endif
1036 
1037 	/* length of ethernet packet */
1038 	len = (uchar *)s - ((uchar *)NetTxPacket + ETHER_HDR_SIZE);
1039 	et->et_protlen = htons(len);
1040 
1041 	len = ETHER_HDR_SIZE + sizeof(CDP_SNAP_hdr);
1042 	chksum = CDP_compute_csum((uchar *)NetTxPacket + len,
1043 				  (uchar *)s - (NetTxPacket + len));
1044 	if (chksum == 0)
1045 		chksum = 0xFFFF;
1046 	*cp = htons(chksum);
1047 
1048 	(void) eth_send(NetTxPacket, (uchar *)s - NetTxPacket);
1049 	return 0;
1050 }
1051 
1052 static void
1053 CDPTimeout(void)
1054 {
1055 	CDPSeq++;
1056 
1057 	if (CDPSeq < 3) {
1058 		NetSetTimeout(CDP_TIMEOUT, CDPTimeout);
1059 		CDPSendTrigger();
1060 		return;
1061 	}
1062 
1063 	/* if not OK try again */
1064 	if (!CDPOK)
1065 		NetStartAgain();
1066 	else
1067 		NetState = NETLOOP_SUCCESS;
1068 }
1069 
1070 static void
1071 CDPDummyHandler(uchar *pkt, unsigned dest, IPaddr_t sip, unsigned src,
1072 		unsigned len)
1073 {
1074 	/* nothing */
1075 }
1076 
1077 static void
1078 CDPHandler(const uchar *pkt, unsigned len)
1079 {
1080 	const uchar *t;
1081 	const ushort *ss;
1082 	ushort type, tlen;
1083 	ushort vlan, nvlan;
1084 
1085 	/* minimum size? */
1086 	if (len < sizeof(CDP_SNAP_hdr) + 4)
1087 		goto pkt_short;
1088 
1089 	/* check for valid CDP SNAP header */
1090 	if (memcmp(pkt, CDP_SNAP_hdr, sizeof(CDP_SNAP_hdr)) != 0)
1091 		return;
1092 
1093 	pkt += sizeof(CDP_SNAP_hdr);
1094 	len -= sizeof(CDP_SNAP_hdr);
1095 
1096 	/* Version of CDP protocol must be >= 2 and TTL != 0 */
1097 	if (pkt[0] < 0x02 || pkt[1] == 0)
1098 		return;
1099 
1100 	/*
1101 	 * if version is greater than 0x02 maybe we'll have a problem;
1102 	 * output a warning
1103 	 */
1104 	if (pkt[0] != 0x02)
1105 		printf("** WARNING: CDP packet received with a protocol version %d > 2\n",
1106 				pkt[0] & 0xff);
1107 
1108 	if (CDP_compute_csum(pkt, len) != 0)
1109 		return;
1110 
1111 	pkt += 4;
1112 	len -= 4;
1113 
1114 	vlan = htons(-1);
1115 	nvlan = htons(-1);
1116 	while (len > 0) {
1117 		if (len < 4)
1118 			goto pkt_short;
1119 
1120 		ss = (const ushort *)pkt;
1121 		type = ntohs(ss[0]);
1122 		tlen = ntohs(ss[1]);
1123 		if (tlen > len)
1124 			goto pkt_short;
1125 
1126 		pkt += tlen;
1127 		len -= tlen;
1128 
1129 		ss += 2;	/* point ss to the data of the TLV */
1130 		tlen -= 4;
1131 
1132 		switch (type) {
1133 		case CDP_DEVICE_ID_TLV:
1134 			break;
1135 		case CDP_ADDRESS_TLV:
1136 			break;
1137 		case CDP_PORT_ID_TLV:
1138 			break;
1139 		case CDP_CAPABILITIES_TLV:
1140 			break;
1141 		case CDP_VERSION_TLV:
1142 			break;
1143 		case CDP_PLATFORM_TLV:
1144 			break;
1145 		case CDP_NATIVE_VLAN_TLV:
1146 			nvlan = *ss;
1147 			break;
1148 		case CDP_APPLIANCE_VLAN_TLV:
1149 			t = (const uchar *)ss;
1150 			while (tlen > 0) {
1151 				if (tlen < 3)
1152 					goto pkt_short;
1153 
1154 				ss = (const ushort *)(t + 1);
1155 
1156 #ifdef CONFIG_CDP_APPLIANCE_VLAN_TYPE
1157 				if (t[0] == CONFIG_CDP_APPLIANCE_VLAN_TYPE)
1158 					vlan = *ss;
1159 #else
1160 				/* XXX will this work; dunno */
1161 				vlan = ntohs(*ss);
1162 #endif
1163 				t += 3; tlen -= 3;
1164 			}
1165 			break;
1166 		case CDP_TRIGGER_TLV:
1167 			break;
1168 		case CDP_POWER_CONSUMPTION_TLV:
1169 			break;
1170 		case CDP_SYSNAME_TLV:
1171 			break;
1172 		case CDP_SYSOBJECT_TLV:
1173 			break;
1174 		case CDP_MANAGEMENT_ADDRESS_TLV:
1175 			break;
1176 		}
1177 	}
1178 
1179 	CDPApplianceVLAN = vlan;
1180 	CDPNativeVLAN = nvlan;
1181 
1182 	CDPOK = 1;
1183 	return;
1184 
1185  pkt_short:
1186 	printf("** CDP packet is too short\n");
1187 	return;
1188 }
1189 
1190 static void CDPStart(void)
1191 {
1192 	printf("Using %s device\n", eth_get_name());
1193 	CDPSeq = 0;
1194 	CDPOK = 0;
1195 
1196 	CDPNativeVLAN = htons(-1);
1197 	CDPApplianceVLAN = htons(-1);
1198 
1199 	NetSetTimeout(CDP_TIMEOUT, CDPTimeout);
1200 	NetSetHandler(CDPDummyHandler);
1201 
1202 	CDPSendTrigger();
1203 }
1204 #endif
1205 
1206 #ifdef CONFIG_IP_DEFRAG
1207 /*
1208  * This function collects fragments in a single packet, according
1209  * to the algorithm in RFC815. It returns NULL or the pointer to
1210  * a complete packet, in static storage
1211  */
1212 #ifndef CONFIG_NET_MAXDEFRAG
1213 #define CONFIG_NET_MAXDEFRAG 16384
1214 #endif
1215 /*
1216  * MAXDEFRAG, above, is chosen in the config file and  is real data
1217  * so we need to add the NFS overhead, which is more than TFTP.
1218  * To use sizeof in the internal unnamed structures, we need a real
1219  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
1220  * The compiler doesn't complain nor allocates the actual structure
1221  */
1222 static struct rpc_t rpc_specimen;
1223 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
1224 
1225 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE_NO_UDP)
1226 
1227 /*
1228  * this is the packet being assembled, either data or frag control.
1229  * Fragments go by 8 bytes, so this union must be 8 bytes long
1230  */
1231 struct hole {
1232 	/* first_byte is address of this structure */
1233 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
1234 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
1235 	u16 prev_hole;	/* index of prev, 0 == none */
1236 	u16 unused;
1237 };
1238 
1239 static IP_t *__NetDefragment(IP_t *ip, int *lenp)
1240 {
1241 	static uchar pkt_buff[IP_PKTSIZE] __attribute__((aligned(PKTALIGN)));
1242 	static u16 first_hole, total_len;
1243 	struct hole *payload, *thisfrag, *h, *newh;
1244 	IP_t *localip = (IP_t *)pkt_buff;
1245 	uchar *indata = (uchar *)ip;
1246 	int offset8, start, len, done = 0;
1247 	u16 ip_off = ntohs(ip->ip_off);
1248 
1249 	/* payload starts after IP header, this fragment is in there */
1250 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE_NO_UDP);
1251 	offset8 =  (ip_off & IP_OFFS);
1252 	thisfrag = payload + offset8;
1253 	start = offset8 * 8;
1254 	len = ntohs(ip->ip_len) - IP_HDR_SIZE_NO_UDP;
1255 
1256 	if (start + len > IP_MAXUDP) /* fragment extends too far */
1257 		return NULL;
1258 
1259 	if (!total_len || localip->ip_id != ip->ip_id) {
1260 		/* new (or different) packet, reset structs */
1261 		total_len = 0xffff;
1262 		payload[0].last_byte = ~0;
1263 		payload[0].next_hole = 0;
1264 		payload[0].prev_hole = 0;
1265 		first_hole = 0;
1266 		/* any IP header will work, copy the first we received */
1267 		memcpy(localip, ip, IP_HDR_SIZE_NO_UDP);
1268 	}
1269 
1270 	/*
1271 	 * What follows is the reassembly algorithm. We use the payload
1272 	 * array as a linked list of hole descriptors, as each hole starts
1273 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
1274 	 * so it is represented as byte count, not as 8-byte blocks.
1275 	 */
1276 
1277 	h = payload + first_hole;
1278 	while (h->last_byte < start) {
1279 		if (!h->next_hole) {
1280 			/* no hole that far away */
1281 			return NULL;
1282 		}
1283 		h = payload + h->next_hole;
1284 	}
1285 
1286 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
1287 	if (offset8 + ((len + 7) / 8) <= h - payload) {
1288 		/* no overlap with holes (dup fragment?) */
1289 		return NULL;
1290 	}
1291 
1292 	if (!(ip_off & IP_FLAGS_MFRAG)) {
1293 		/* no more fragmentss: truncate this (last) hole */
1294 		total_len = start + len;
1295 		h->last_byte = start + len;
1296 	}
1297 
1298 	/*
1299 	 * There is some overlap: fix the hole list. This code doesn't
1300 	 * deal with a fragment that overlaps with two different holes
1301 	 * (thus being a superset of a previously-received fragment).
1302 	 */
1303 
1304 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
1305 		/* complete overlap with hole: remove hole */
1306 		if (!h->prev_hole && !h->next_hole) {
1307 			/* last remaining hole */
1308 			done = 1;
1309 		} else if (!h->prev_hole) {
1310 			/* first hole */
1311 			first_hole = h->next_hole;
1312 			payload[h->next_hole].prev_hole = 0;
1313 		} else if (!h->next_hole) {
1314 			/* last hole */
1315 			payload[h->prev_hole].next_hole = 0;
1316 		} else {
1317 			/* in the middle of the list */
1318 			payload[h->next_hole].prev_hole = h->prev_hole;
1319 			payload[h->prev_hole].next_hole = h->next_hole;
1320 		}
1321 
1322 	} else if (h->last_byte <= start + len) {
1323 		/* overlaps with final part of the hole: shorten this hole */
1324 		h->last_byte = start;
1325 
1326 	} else if (h >= thisfrag) {
1327 		/* overlaps with initial part of the hole: move this hole */
1328 		newh = thisfrag + (len / 8);
1329 		*newh = *h;
1330 		h = newh;
1331 		if (h->next_hole)
1332 			payload[h->next_hole].prev_hole = (h - payload);
1333 		if (h->prev_hole)
1334 			payload[h->prev_hole].next_hole = (h - payload);
1335 		else
1336 			first_hole = (h - payload);
1337 
1338 	} else {
1339 		/* fragment sits in the middle: split the hole */
1340 		newh = thisfrag + (len / 8);
1341 		*newh = *h;
1342 		h->last_byte = start;
1343 		h->next_hole = (newh - payload);
1344 		newh->prev_hole = (h - payload);
1345 		if (newh->next_hole)
1346 			payload[newh->next_hole].prev_hole = (newh - payload);
1347 	}
1348 
1349 	/* finally copy this fragment and possibly return whole packet */
1350 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE_NO_UDP, len);
1351 	if (!done)
1352 		return NULL;
1353 
1354 	localip->ip_len = htons(total_len);
1355 	*lenp = total_len + IP_HDR_SIZE_NO_UDP;
1356 	return localip;
1357 }
1358 
1359 static inline IP_t *NetDefragment(IP_t *ip, int *lenp)
1360 {
1361 	u16 ip_off = ntohs(ip->ip_off);
1362 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
1363 		return ip; /* not a fragment */
1364 	return __NetDefragment(ip, lenp);
1365 }
1366 
1367 #else /* !CONFIG_IP_DEFRAG */
1368 
1369 static inline IP_t *NetDefragment(IP_t *ip, int *lenp)
1370 {
1371 	u16 ip_off = ntohs(ip->ip_off);
1372 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
1373 		return ip; /* not a fragment */
1374 	return NULL;
1375 }
1376 #endif
1377 
1378 /**
1379  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
1380  * drop others.
1381  *
1382  * @parma ip	IP packet containing the ICMP
1383  */
1384 static void receive_icmp(IP_t *ip, int len, IPaddr_t src_ip, Ethernet_t *et)
1385 {
1386 	ICMP_t *icmph = (ICMP_t *)&ip->udp_src;
1387 
1388 	switch (icmph->type) {
1389 	case ICMP_REDIRECT:
1390 		if (icmph->code != ICMP_REDIR_HOST)
1391 			return;
1392 		printf(" ICMP Host Redirect to %pI4 ",
1393 			&icmph->un.gateway);
1394 		break;
1395 #if defined(CONFIG_CMD_PING)
1396 	case ICMP_ECHO_REPLY:
1397 		/*
1398 			* IP header OK.  Pass the packet to the
1399 			* current handler.
1400 			*/
1401 		/*
1402 		 * XXX point to ip packet - should this use
1403 		 * packet_icmp_handler?
1404 		 */
1405 		(*packetHandler)((uchar *)ip, 0, src_ip, 0, 0);
1406 		break;
1407 	case ICMP_ECHO_REQUEST:
1408 		debug("Got ICMP ECHO REQUEST, return %d bytes\n",
1409 			ETHER_HDR_SIZE + len);
1410 
1411 		memcpy(&et->et_dest[0], &et->et_src[0], 6);
1412 		memcpy(&et->et_src[0], NetOurEther, 6);
1413 
1414 		ip->ip_sum = 0;
1415 		ip->ip_off = 0;
1416 		NetCopyIP((void *)&ip->ip_dst, &ip->ip_src);
1417 		NetCopyIP((void *)&ip->ip_src, &NetOurIP);
1418 		ip->ip_sum = ~NetCksum((uchar *)ip,
1419 					IP_HDR_SIZE_NO_UDP >> 1);
1420 
1421 		icmph->type = ICMP_ECHO_REPLY;
1422 		icmph->checksum = 0;
1423 		icmph->checksum = ~NetCksum((uchar *)icmph,
1424 			(len - IP_HDR_SIZE_NO_UDP) >> 1);
1425 		(void) eth_send((uchar *)et,
1426 				ETHER_HDR_SIZE + len);
1427 		break;
1428 #endif
1429 	default:
1430 #ifdef CONFIG_CMD_TFTPPUT
1431 		if (packet_icmp_handler)
1432 			packet_icmp_handler(icmph->type, icmph->code,
1433 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
1434 				icmph->un.data, ntohs(ip->udp_len));
1435 #endif
1436 		break;
1437 	}
1438 }
1439 
1440 void
1441 NetReceive(volatile uchar *inpkt, int len)
1442 {
1443 	Ethernet_t *et;
1444 	IP_t	*ip;
1445 	ARP_t	*arp;
1446 	IPaddr_t tmp;
1447 	IPaddr_t src_ip;
1448 	int	x;
1449 	uchar *pkt;
1450 #if defined(CONFIG_CMD_CDP)
1451 	int iscdp;
1452 #endif
1453 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
1454 
1455 	debug("packet received\n");
1456 
1457 	NetRxPacket = inpkt;
1458 	NetRxPacketLen = len;
1459 	et = (Ethernet_t *)inpkt;
1460 
1461 	/* too small packet? */
1462 	if (len < ETHER_HDR_SIZE)
1463 		return;
1464 
1465 #ifdef CONFIG_API
1466 	if (push_packet) {
1467 		(*push_packet)(inpkt, len);
1468 		return;
1469 	}
1470 #endif
1471 
1472 #if defined(CONFIG_CMD_CDP)
1473 	/* keep track if packet is CDP */
1474 	iscdp = memcmp(et->et_dest, NetCDPAddr, 6) == 0;
1475 #endif
1476 
1477 	myvlanid = ntohs(NetOurVLAN);
1478 	if (myvlanid == (ushort)-1)
1479 		myvlanid = VLAN_NONE;
1480 	mynvlanid = ntohs(NetOurNativeVLAN);
1481 	if (mynvlanid == (ushort)-1)
1482 		mynvlanid = VLAN_NONE;
1483 
1484 	x = ntohs(et->et_protlen);
1485 
1486 	debug("packet received\n");
1487 
1488 	if (x < 1514) {
1489 		/*
1490 		 *	Got a 802 packet.  Check the other protocol field.
1491 		 */
1492 		x = ntohs(et->et_prot);
1493 
1494 		ip = (IP_t *)(inpkt + E802_HDR_SIZE);
1495 		len -= E802_HDR_SIZE;
1496 
1497 	} else if (x != PROT_VLAN) {	/* normal packet */
1498 		ip = (IP_t *)(inpkt + ETHER_HDR_SIZE);
1499 		len -= ETHER_HDR_SIZE;
1500 
1501 	} else {			/* VLAN packet */
1502 		VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)et;
1503 
1504 		debug("VLAN packet received\n");
1505 
1506 		/* too small packet? */
1507 		if (len < VLAN_ETHER_HDR_SIZE)
1508 			return;
1509 
1510 		/* if no VLAN active */
1511 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1512 #if defined(CONFIG_CMD_CDP)
1513 				&& iscdp == 0
1514 #endif
1515 				)
1516 			return;
1517 
1518 		cti = ntohs(vet->vet_tag);
1519 		vlanid = cti & VLAN_IDMASK;
1520 		x = ntohs(vet->vet_type);
1521 
1522 		ip = (IP_t *)(inpkt + VLAN_ETHER_HDR_SIZE);
1523 		len -= VLAN_ETHER_HDR_SIZE;
1524 	}
1525 
1526 	debug("Receive from protocol 0x%x\n", x);
1527 
1528 #if defined(CONFIG_CMD_CDP)
1529 	if (iscdp) {
1530 		CDPHandler((uchar *)ip, len);
1531 		return;
1532 	}
1533 #endif
1534 
1535 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1536 		if (vlanid == VLAN_NONE)
1537 			vlanid = (mynvlanid & VLAN_IDMASK);
1538 		/* not matched? */
1539 		if (vlanid != (myvlanid & VLAN_IDMASK))
1540 			return;
1541 	}
1542 
1543 	switch (x) {
1544 
1545 	case PROT_ARP:
1546 		/*
1547 		 * We have to deal with two types of ARP packets:
1548 		 * - REQUEST packets will be answered by sending  our
1549 		 *   IP address - if we know it.
1550 		 * - REPLY packates are expected only after we asked
1551 		 *   for the TFTP server's or the gateway's ethernet
1552 		 *   address; so if we receive such a packet, we set
1553 		 *   the server ethernet address
1554 		 */
1555 		debug("Got ARP\n");
1556 
1557 		arp = (ARP_t *)ip;
1558 		if (len < ARP_HDR_SIZE) {
1559 			printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
1560 			return;
1561 		}
1562 		if (ntohs(arp->ar_hrd) != ARP_ETHER)
1563 			return;
1564 		if (ntohs(arp->ar_pro) != PROT_IP)
1565 			return;
1566 		if (arp->ar_hln != 6)
1567 			return;
1568 		if (arp->ar_pln != 4)
1569 			return;
1570 
1571 		if (NetOurIP == 0)
1572 			return;
1573 
1574 		if (NetReadIP(&arp->ar_data[16]) != NetOurIP)
1575 			return;
1576 
1577 		switch (ntohs(arp->ar_op)) {
1578 		case ARPOP_REQUEST:
1579 			/* reply with our IP address */
1580 			debug("Got ARP REQUEST, return our IP\n");
1581 			pkt = (uchar *)et;
1582 			pkt += NetSetEther(pkt, et->et_src, PROT_ARP);
1583 			arp->ar_op = htons(ARPOP_REPLY);
1584 			memcpy(&arp->ar_data[10], &arp->ar_data[0], 6);
1585 			NetCopyIP(&arp->ar_data[16], &arp->ar_data[6]);
1586 			memcpy(&arp->ar_data[0], NetOurEther, 6);
1587 			NetCopyIP(&arp->ar_data[6], &NetOurIP);
1588 			(void) eth_send((uchar *)et,
1589 					(pkt - (uchar *)et) + ARP_HDR_SIZE);
1590 			return;
1591 
1592 		case ARPOP_REPLY:		/* arp reply */
1593 			/* are we waiting for a reply */
1594 			if (!NetArpWaitPacketIP || !NetArpWaitPacketMAC)
1595 				break;
1596 
1597 #ifdef CONFIG_KEEP_SERVERADDR
1598 			if (NetServerIP == NetArpWaitPacketIP) {
1599 				char buf[20];
1600 				sprintf(buf, "%pM", arp->ar_data);
1601 				setenv("serveraddr", buf);
1602 			}
1603 #endif
1604 
1605 			debug("Got ARP REPLY, set server/gtwy eth addr (%pM)\n",
1606 				arp->ar_data);
1607 
1608 			tmp = NetReadIP(&arp->ar_data[6]);
1609 
1610 			/* matched waiting packet's address */
1611 			if (tmp == NetArpWaitReplyIP) {
1612 				debug("Got it\n");
1613 				/* save address for later use */
1614 				memcpy(NetArpWaitPacketMAC,
1615 				       &arp->ar_data[0], 6);
1616 
1617 #ifdef CONFIG_NETCONSOLE
1618 				(*packetHandler)(0, 0, 0, 0, 0);
1619 #endif
1620 				/* modify header, and transmit it */
1621 				memcpy(((Ethernet_t *)NetArpWaitTxPacket)->et_dest, NetArpWaitPacketMAC, 6);
1622 				(void) eth_send(NetArpWaitTxPacket,
1623 						NetArpWaitTxPacketSize);
1624 
1625 				/* no arp request pending now */
1626 				NetArpWaitPacketIP = 0;
1627 				NetArpWaitTxPacketSize = 0;
1628 				NetArpWaitPacketMAC = NULL;
1629 
1630 			}
1631 			return;
1632 		default:
1633 			debug("Unexpected ARP opcode 0x%x\n",
1634 			      ntohs(arp->ar_op));
1635 			return;
1636 		}
1637 		break;
1638 
1639 #ifdef CONFIG_CMD_RARP
1640 	case PROT_RARP:
1641 		debug("Got RARP\n");
1642 		arp = (ARP_t *)ip;
1643 		if (len < ARP_HDR_SIZE) {
1644 			printf("bad length %d < %d\n", len, ARP_HDR_SIZE);
1645 			return;
1646 		}
1647 
1648 		if ((ntohs(arp->ar_op) != RARPOP_REPLY) ||
1649 			(ntohs(arp->ar_hrd) != ARP_ETHER)   ||
1650 			(ntohs(arp->ar_pro) != PROT_IP)     ||
1651 			(arp->ar_hln != 6) || (arp->ar_pln != 4)) {
1652 
1653 			puts("invalid RARP header\n");
1654 		} else {
1655 			NetCopyIP(&NetOurIP, &arp->ar_data[16]);
1656 			if (NetServerIP == 0)
1657 				NetCopyIP(&NetServerIP, &arp->ar_data[6]);
1658 			memcpy(NetServerEther, &arp->ar_data[0], 6);
1659 
1660 			(*packetHandler)(0, 0, 0, 0, 0);
1661 		}
1662 		break;
1663 #endif
1664 	case PROT_IP:
1665 		debug("Got IP\n");
1666 		/* Before we start poking the header, make sure it is there */
1667 		if (len < IP_HDR_SIZE) {
1668 			debug("len bad %d < %lu\n", len, (ulong)IP_HDR_SIZE);
1669 			return;
1670 		}
1671 		/* Check the packet length */
1672 		if (len < ntohs(ip->ip_len)) {
1673 			printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
1674 			return;
1675 		}
1676 		len = ntohs(ip->ip_len);
1677 		debug("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
1678 
1679 		/* Can't deal with anything except IPv4 */
1680 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1681 			return;
1682 		/* Can't deal with IP options (headers != 20 bytes) */
1683 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1684 			return;
1685 		/* Check the Checksum of the header */
1686 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2)) {
1687 			puts("checksum bad\n");
1688 			return;
1689 		}
1690 		/* If it is not for us, ignore it */
1691 		tmp = NetReadIP(&ip->ip_dst);
1692 		if (NetOurIP && tmp != NetOurIP && tmp != 0xFFFFFFFF) {
1693 #ifdef CONFIG_MCAST_TFTP
1694 			if (Mcast_addr != tmp)
1695 #endif
1696 				return;
1697 		}
1698 		/* Read source IP address for later use */
1699 		src_ip = NetReadIP(&ip->ip_src);
1700 		/*
1701 		 * The function returns the unchanged packet if it's not
1702 		 * a fragment, and either the complete packet or NULL if
1703 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1704 		 */
1705 		ip = NetDefragment(ip, &len);
1706 		if (!ip)
1707 			return;
1708 		/*
1709 		 * watch for ICMP host redirects
1710 		 *
1711 		 * There is no real handler code (yet). We just watch
1712 		 * for ICMP host redirect messages. In case anybody
1713 		 * sees these messages: please contact me
1714 		 * (wd@denx.de), or - even better - send me the
1715 		 * necessary fixes :-)
1716 		 *
1717 		 * Note: in all cases where I have seen this so far
1718 		 * it was a problem with the router configuration,
1719 		 * for instance when a router was configured in the
1720 		 * BOOTP reply, but the TFTP server was on the same
1721 		 * subnet. So this is probably a warning that your
1722 		 * configuration might be wrong. But I'm not really
1723 		 * sure if there aren't any other situations.
1724 		 *
1725 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1726 		 * we send a tftp packet to a dead connection, or when
1727 		 * there is no server at the other end.
1728 		 */
1729 		if (ip->ip_p == IPPROTO_ICMP) {
1730 			receive_icmp(ip, len, src_ip, et);
1731 			return;
1732 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1733 			return;
1734 		}
1735 
1736 #ifdef CONFIG_UDP_CHECKSUM
1737 		if (ip->udp_xsum != 0) {
1738 			ulong   xsum;
1739 			ushort *sumptr;
1740 			ushort  sumlen;
1741 
1742 			xsum  = ip->ip_p;
1743 			xsum += (ntohs(ip->udp_len));
1744 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1745 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1746 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1747 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1748 
1749 			sumlen = ntohs(ip->udp_len);
1750 			sumptr = (ushort *) &(ip->udp_src);
1751 
1752 			while (sumlen > 1) {
1753 				ushort sumdata;
1754 
1755 				sumdata = *sumptr++;
1756 				xsum += ntohs(sumdata);
1757 				sumlen -= 2;
1758 			}
1759 			if (sumlen > 0) {
1760 				ushort sumdata;
1761 
1762 				sumdata = *(unsigned char *) sumptr;
1763 				sumdata = (sumdata << 8) & 0xff00;
1764 				xsum += sumdata;
1765 			}
1766 			while ((xsum >> 16) != 0) {
1767 				xsum = (xsum & 0x0000ffff) +
1768 				       ((xsum >> 16) & 0x0000ffff);
1769 			}
1770 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1771 				printf(" UDP wrong checksum %08lx %08x\n",
1772 					xsum, ntohs(ip->udp_xsum));
1773 				return;
1774 			}
1775 		}
1776 #endif
1777 
1778 
1779 #ifdef CONFIG_NETCONSOLE
1780 		nc_input_packet((uchar *)ip + IP_HDR_SIZE,
1781 						ntohs(ip->udp_dst),
1782 						ntohs(ip->udp_src),
1783 						ntohs(ip->udp_len) - 8);
1784 #endif
1785 		/*
1786 		 *	IP header OK.  Pass the packet to the current handler.
1787 		 */
1788 		(*packetHandler)((uchar *)ip + IP_HDR_SIZE,
1789 						ntohs(ip->udp_dst),
1790 						src_ip,
1791 						ntohs(ip->udp_src),
1792 						ntohs(ip->udp_len) - 8);
1793 		break;
1794 	}
1795 }
1796 
1797 
1798 /**********************************************************************/
1799 
1800 static int net_check_prereq(enum proto_t protocol)
1801 {
1802 	switch (protocol) {
1803 		/* Fall through */
1804 #if defined(CONFIG_CMD_PING)
1805 	case PING:
1806 		if (NetPingIP == 0) {
1807 			puts("*** ERROR: ping address not given\n");
1808 			return 1;
1809 		}
1810 		goto common;
1811 #endif
1812 #if defined(CONFIG_CMD_SNTP)
1813 	case SNTP:
1814 		if (NetNtpServerIP == 0) {
1815 			puts("*** ERROR: NTP server address not given\n");
1816 			return 1;
1817 		}
1818 		goto common;
1819 #endif
1820 #if defined(CONFIG_CMD_DNS)
1821 	case DNS:
1822 		if (NetOurDNSIP == 0) {
1823 			puts("*** ERROR: DNS server address not given\n");
1824 			return 1;
1825 		}
1826 		goto common;
1827 #endif
1828 #if defined(CONFIG_CMD_NFS)
1829 	case NFS:
1830 #endif
1831 	case TFTPGET:
1832 	case TFTPPUT:
1833 		if (NetServerIP == 0) {
1834 			puts("*** ERROR: `serverip' not set\n");
1835 			return 1;
1836 		}
1837 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1838 	defined(CONFIG_CMD_DNS)
1839 common:
1840 #endif
1841 		/* Fall through */
1842 
1843 	case NETCONS:
1844 	case TFTPSRV:
1845 		if (NetOurIP == 0) {
1846 			puts("*** ERROR: `ipaddr' not set\n");
1847 			return 1;
1848 		}
1849 		/* Fall through */
1850 
1851 #ifdef CONFIG_CMD_RARP
1852 	case RARP:
1853 #endif
1854 	case BOOTP:
1855 	case CDP:
1856 	case DHCP:
1857 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1858 			extern int eth_get_dev_index(void);
1859 			int num = eth_get_dev_index();
1860 
1861 			switch (num) {
1862 			case -1:
1863 				puts("*** ERROR: No ethernet found.\n");
1864 				return 1;
1865 			case 0:
1866 				puts("*** ERROR: `ethaddr' not set\n");
1867 				break;
1868 			default:
1869 				printf("*** ERROR: `eth%daddr' not set\n",
1870 					num);
1871 				break;
1872 			}
1873 
1874 			NetStartAgain();
1875 			return 2;
1876 		}
1877 		/* Fall through */
1878 	default:
1879 		return 0;
1880 	}
1881 	return 0;		/* OK */
1882 }
1883 /**********************************************************************/
1884 
1885 int
1886 NetCksumOk(uchar *ptr, int len)
1887 {
1888 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1889 }
1890 
1891 
1892 unsigned
1893 NetCksum(uchar *ptr, int len)
1894 {
1895 	ulong	xsum;
1896 	ushort *p = (ushort *)ptr;
1897 
1898 	xsum = 0;
1899 	while (len-- > 0)
1900 		xsum += *p++;
1901 	xsum = (xsum & 0xffff) + (xsum >> 16);
1902 	xsum = (xsum & 0xffff) + (xsum >> 16);
1903 	return xsum & 0xffff;
1904 }
1905 
1906 int
1907 NetEthHdrSize(void)
1908 {
1909 	ushort myvlanid;
1910 
1911 	myvlanid = ntohs(NetOurVLAN);
1912 	if (myvlanid == (ushort)-1)
1913 		myvlanid = VLAN_NONE;
1914 
1915 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1916 		VLAN_ETHER_HDR_SIZE;
1917 }
1918 
1919 int
1920 NetSetEther(volatile uchar *xet, uchar * addr, uint prot)
1921 {
1922 	Ethernet_t *et = (Ethernet_t *)xet;
1923 	ushort myvlanid;
1924 
1925 	myvlanid = ntohs(NetOurVLAN);
1926 	if (myvlanid == (ushort)-1)
1927 		myvlanid = VLAN_NONE;
1928 
1929 	memcpy(et->et_dest, addr, 6);
1930 	memcpy(et->et_src, NetOurEther, 6);
1931 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1932 		et->et_protlen = htons(prot);
1933 		return ETHER_HDR_SIZE;
1934 	} else {
1935 		VLAN_Ethernet_t *vet = (VLAN_Ethernet_t *)xet;
1936 
1937 		vet->vet_vlan_type = htons(PROT_VLAN);
1938 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1939 		vet->vet_type = htons(prot);
1940 		return VLAN_ETHER_HDR_SIZE;
1941 	}
1942 }
1943 
1944 void
1945 NetSetIP(volatile uchar *xip, IPaddr_t dest, int dport, int sport, int len)
1946 {
1947 	IP_t *ip = (IP_t *)xip;
1948 
1949 	/*
1950 	 *	If the data is an odd number of bytes, zero the
1951 	 *	byte after the last byte so that the checksum
1952 	 *	will work.
1953 	 */
1954 	if (len & 1)
1955 		xip[IP_HDR_SIZE + len] = 0;
1956 
1957 	/*
1958 	 *	Construct an IP and UDP header.
1959 	 *	(need to set no fragment bit - XXX)
1960 	 */
1961 	/* IP_HDR_SIZE / 4 (not including UDP) */
1962 	ip->ip_hl_v  = 0x45;
1963 	ip->ip_tos   = 0;
1964 	ip->ip_len   = htons(IP_HDR_SIZE + len);
1965 	ip->ip_id    = htons(NetIPID++);
1966 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1967 	ip->ip_ttl   = 255;
1968 	ip->ip_p     = 17;		/* UDP */
1969 	ip->ip_sum   = 0;
1970 	/* already in network byte order */
1971 	NetCopyIP((void *)&ip->ip_src, &NetOurIP);
1972 	/* - "" - */
1973 	NetCopyIP((void *)&ip->ip_dst, &dest);
1974 	ip->udp_src  = htons(sport);
1975 	ip->udp_dst  = htons(dport);
1976 	ip->udp_len  = htons(8 + len);
1977 	ip->udp_xsum = 0;
1978 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE_NO_UDP / 2);
1979 }
1980 
1981 void copy_filename(char *dst, const char *src, int size)
1982 {
1983 	if (*src && (*src == '"')) {
1984 		++src;
1985 		--size;
1986 	}
1987 
1988 	while ((--size > 0) && *src && (*src != '"'))
1989 		*dst++ = *src++;
1990 	*dst = '\0';
1991 }
1992 
1993 #if	defined(CONFIG_CMD_NFS)		|| \
1994 	defined(CONFIG_CMD_SNTP)	|| \
1995 	defined(CONFIG_CMD_DNS)
1996 /*
1997  * make port a little random (1024-17407)
1998  * This keeps the math somewhat trivial to compute, and seems to work with
1999  * all supported protocols/clients/servers
2000  */
2001 unsigned int random_port(void)
2002 {
2003 	return 1024 + (get_timer(0) % 0x4000);
2004 }
2005 #endif
2006 
2007 void ip_to_string(IPaddr_t x, char *s)
2008 {
2009 	x = ntohl(x);
2010 	sprintf(s, "%d.%d.%d.%d",
2011 		(int) ((x >> 24) & 0xff),
2012 		(int) ((x >> 16) & 0xff),
2013 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
2014 	);
2015 }
2016 
2017 void VLAN_to_string(ushort x, char *s)
2018 {
2019 	x = ntohs(x);
2020 
2021 	if (x == (ushort)-1)
2022 		x = VLAN_NONE;
2023 
2024 	if (x == VLAN_NONE)
2025 		strcpy(s, "none");
2026 	else
2027 		sprintf(s, "%d", x & VLAN_IDMASK);
2028 }
2029 
2030 ushort string_to_VLAN(const char *s)
2031 {
2032 	ushort id;
2033 
2034 	if (s == NULL)
2035 		return htons(VLAN_NONE);
2036 
2037 	if (*s < '0' || *s > '9')
2038 		id = VLAN_NONE;
2039 	else
2040 		id = (ushort)simple_strtoul(s, NULL, 10);
2041 
2042 	return htons(id);
2043 }
2044 
2045 ushort getenv_VLAN(char *var)
2046 {
2047 	return string_to_VLAN(getenv(var));
2048 }
2049