xref: /rk3399_rockchip-uboot/net/net.c (revision d22c338e07cc98276ea5cc4feaa5a370baa63243)
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  * LINK_LOCAL:
27  *
28  *	Prerequisites:	- own ethernet address
29  *	We want:	- own IP address
30  *	Next step:	ARP
31  *
32  * RARP:
33  *
34  *	Prerequisites:	- own ethernet address
35  *	We want:	- own IP address
36  *			- TFTP server IP address
37  *	Next step:	ARP
38  *
39  * ARP:
40  *
41  *	Prerequisites:	- own ethernet address
42  *			- own IP address
43  *			- TFTP server IP address
44  *	We want:	- TFTP server ethernet address
45  *	Next step:	TFTP
46  *
47  * DHCP:
48  *
49  *     Prerequisites:	- own ethernet address
50  *     We want:		- IP, Netmask, ServerIP, Gateway IP
51  *			- bootfilename, lease time
52  *     Next step:	- TFTP
53  *
54  * TFTP:
55  *
56  *	Prerequisites:	- own ethernet address
57  *			- own IP address
58  *			- TFTP server IP address
59  *			- TFTP server ethernet address
60  *			- name of bootfile (if unknown, we use a default name
61  *			  derived from our own IP address)
62  *	We want:	- load the boot file
63  *	Next step:	none
64  *
65  * NFS:
66  *
67  *	Prerequisites:	- own ethernet address
68  *			- own IP address
69  *			- name of bootfile (if unknown, we use a default name
70  *			  derived from our own IP address)
71  *	We want:	- load the boot file
72  *	Next step:	none
73  *
74  * SNTP:
75  *
76  *	Prerequisites:	- own ethernet address
77  *			- own IP address
78  *	We want:	- network time
79  *	Next step:	none
80  */
81 
82 
83 #include <common.h>
84 #include <command.h>
85 #include <net.h>
86 #if defined(CONFIG_STATUS_LED)
87 #include <miiphy.h>
88 #include <status_led.h>
89 #endif
90 #include <watchdog.h>
91 #include <linux/compiler.h>
92 #include "arp.h"
93 #include "bootp.h"
94 #include "cdp.h"
95 #if defined(CONFIG_CMD_DNS)
96 #include "dns.h"
97 #endif
98 #include "link_local.h"
99 #include "nfs.h"
100 #include "ping.h"
101 #include "rarp.h"
102 #if defined(CONFIG_CMD_SNTP)
103 #include "sntp.h"
104 #endif
105 #include "tftp.h"
106 
107 DECLARE_GLOBAL_DATA_PTR;
108 
109 /** BOOTP EXTENTIONS **/
110 
111 /* Our subnet mask (0=unknown) */
112 IPaddr_t	NetOurSubnetMask;
113 /* Our gateways IP address */
114 IPaddr_t	NetOurGatewayIP;
115 /* Our DNS IP address */
116 IPaddr_t	NetOurDNSIP;
117 #if defined(CONFIG_BOOTP_DNS2)
118 /* Our 2nd DNS IP address */
119 IPaddr_t	NetOurDNS2IP;
120 #endif
121 /* Our NIS domain */
122 char		NetOurNISDomain[32] = {0,};
123 /* Our hostname */
124 char		NetOurHostName[32] = {0,};
125 /* Our bootpath */
126 char		NetOurRootPath[64] = {0,};
127 /* Our bootfile size in blocks */
128 ushort		NetBootFileSize;
129 
130 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
131 IPaddr_t Mcast_addr;
132 #endif
133 
134 /** END OF BOOTP EXTENTIONS **/
135 
136 /* The actual transferred size of the bootfile (in bytes) */
137 ulong		NetBootFileXferSize;
138 /* Our ethernet address */
139 uchar		NetOurEther[6];
140 /* Boot server enet address */
141 uchar		NetServerEther[6];
142 /* Our IP addr (0 = unknown) */
143 IPaddr_t	NetOurIP;
144 /* Server IP addr (0 = unknown) */
145 IPaddr_t	NetServerIP;
146 /* Current receive packet */
147 uchar *NetRxPacket;
148 /* Current rx packet length */
149 int		NetRxPacketLen;
150 /* IP packet ID */
151 unsigned	NetIPID;
152 /* Ethernet bcast address */
153 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
154 uchar		NetEtherNullAddr[6];
155 #ifdef CONFIG_API
156 void		(*push_packet)(void *, int len) = 0;
157 #endif
158 /* Network loop state */
159 enum net_loop_state net_state;
160 /* Tried all network devices */
161 int		NetRestartWrap;
162 /* Network loop restarted */
163 static int	NetRestarted;
164 /* At least one device configured */
165 static int	NetDevExists;
166 
167 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
168 /* default is without VLAN */
169 ushort		NetOurVLAN = 0xFFFF;
170 /* ditto */
171 ushort		NetOurNativeVLAN = 0xFFFF;
172 
173 /* Boot File name */
174 char		BootFile[128];
175 
176 #if defined(CONFIG_CMD_SNTP)
177 /* NTP server IP address */
178 IPaddr_t	NetNtpServerIP;
179 /* offset time from UTC */
180 int		NetTimeOffset;
181 #endif
182 
183 uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
184 
185 /* Receive packet */
186 uchar *NetRxPackets[PKTBUFSRX];
187 
188 /* Current UDP RX packet handler */
189 static rxhand_f *udp_packet_handler;
190 /* Current ARP RX packet handler */
191 static rxhand_f *arp_packet_handler;
192 #ifdef CONFIG_CMD_TFTPPUT
193 /* Current ICMP rx handler */
194 static rxhand_icmp_f *packet_icmp_handler;
195 #endif
196 /* Current timeout handler */
197 static thand_f *timeHandler;
198 /* Time base value */
199 static ulong	timeStart;
200 /* Current timeout value */
201 static ulong	timeDelta;
202 /* THE transmit packet */
203 uchar *NetTxPacket;
204 
205 static int net_check_prereq(enum proto_t protocol);
206 
207 static int NetTryCount;
208 
209 /**********************************************************************/
210 
211 /*
212  * Check if autoload is enabled. If so, use either NFS or TFTP to download
213  * the boot file.
214  */
215 void net_auto_load(void)
216 {
217 	const char *s = getenv("autoload");
218 
219 	if (s != NULL) {
220 		if (*s == 'n') {
221 			/*
222 			 * Just use BOOTP/RARP to configure system;
223 			 * Do not use TFTP to load the bootfile.
224 			 */
225 			net_set_state(NETLOOP_SUCCESS);
226 			return;
227 		}
228 #if defined(CONFIG_CMD_NFS)
229 		if (strcmp(s, "NFS") == 0) {
230 			/*
231 			 * Use NFS to load the bootfile.
232 			 */
233 			NfsStart();
234 			return;
235 		}
236 #endif
237 	}
238 	TftpStart(TFTPGET);
239 }
240 
241 static void NetInitLoop(void)
242 {
243 	static int env_changed_id;
244 	int env_id = get_env_id();
245 
246 	/* update only when the environment has changed */
247 	if (env_changed_id != env_id) {
248 		NetOurIP = getenv_IPaddr("ipaddr");
249 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
250 		NetOurSubnetMask = getenv_IPaddr("netmask");
251 		NetServerIP = getenv_IPaddr("serverip");
252 		NetOurNativeVLAN = getenv_VLAN("nvlan");
253 		NetOurVLAN = getenv_VLAN("vlan");
254 #if defined(CONFIG_CMD_DNS)
255 		NetOurDNSIP = getenv_IPaddr("dnsip");
256 #endif
257 		env_changed_id = env_id;
258 	}
259 
260 	return;
261 }
262 
263 static void net_clear_handlers(void)
264 {
265 	net_set_udp_handler(NULL);
266 	net_set_arp_handler(NULL);
267 	NetSetTimeout(0, NULL);
268 }
269 
270 static void net_cleanup_loop(void)
271 {
272 	net_clear_handlers();
273 }
274 
275 void net_init(void)
276 {
277 	static int first_call = 1;
278 
279 	if (first_call) {
280 		/*
281 		 *	Setup packet buffers, aligned correctly.
282 		 */
283 		int i;
284 
285 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
286 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
287 		for (i = 0; i < PKTBUFSRX; i++)
288 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
289 
290 		ArpInit();
291 		net_clear_handlers();
292 
293 		/* Only need to setup buffer pointers once. */
294 		first_call = 0;
295 	}
296 
297 	NetInitLoop();
298 }
299 
300 /**********************************************************************/
301 /*
302  *	Main network processing loop.
303  */
304 
305 int NetLoop(enum proto_t protocol)
306 {
307 	bd_t *bd = gd->bd;
308 	int ret = -1;
309 
310 	NetRestarted = 0;
311 	NetDevExists = 0;
312 	NetTryCount = 1;
313 
314 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
315 	net_init();
316 	eth_halt();
317 	eth_set_current();
318 	if (eth_init(bd) < 0) {
319 		eth_halt();
320 		return -1;
321 	}
322 
323 restart:
324 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
325 
326 	net_set_state(NETLOOP_CONTINUE);
327 
328 	/*
329 	 *	Start the ball rolling with the given start function.  From
330 	 *	here on, this code is a state machine driven by received
331 	 *	packets and timer events.
332 	 */
333 	NetInitLoop();
334 
335 	switch (net_check_prereq(protocol)) {
336 	case 1:
337 		/* network not configured */
338 		eth_halt();
339 		return -1;
340 
341 	case 2:
342 		/* network device not configured */
343 		break;
344 
345 	case 0:
346 		NetDevExists = 1;
347 		NetBootFileXferSize = 0;
348 		switch (protocol) {
349 		case TFTPGET:
350 #ifdef CONFIG_CMD_TFTPPUT
351 		case TFTPPUT:
352 #endif
353 			/* always use ARP to get server ethernet address */
354 			TftpStart(protocol);
355 			break;
356 #ifdef CONFIG_CMD_TFTPSRV
357 		case TFTPSRV:
358 			TftpStartServer();
359 			break;
360 #endif
361 #if defined(CONFIG_CMD_DHCP)
362 		case DHCP:
363 			BootpTry = 0;
364 			NetOurIP = 0;
365 			DhcpRequest();		/* Basically same as BOOTP */
366 			break;
367 #endif
368 
369 		case BOOTP:
370 			BootpTry = 0;
371 			NetOurIP = 0;
372 			BootpRequest();
373 			break;
374 
375 #if defined(CONFIG_CMD_RARP)
376 		case RARP:
377 			RarpTry = 0;
378 			NetOurIP = 0;
379 			RarpRequest();
380 			break;
381 #endif
382 #if defined(CONFIG_CMD_PING)
383 		case PING:
384 			ping_start();
385 			break;
386 #endif
387 #if defined(CONFIG_CMD_NFS)
388 		case NFS:
389 			NfsStart();
390 			break;
391 #endif
392 #if defined(CONFIG_CMD_CDP)
393 		case CDP:
394 			CDPStart();
395 			break;
396 #endif
397 #ifdef CONFIG_NETCONSOLE
398 		case NETCONS:
399 			NcStart();
400 			break;
401 #endif
402 #if defined(CONFIG_CMD_SNTP)
403 		case SNTP:
404 			SntpStart();
405 			break;
406 #endif
407 #if defined(CONFIG_CMD_DNS)
408 		case DNS:
409 			DnsStart();
410 			break;
411 #endif
412 #if defined(CONFIG_CMD_LINK_LOCAL)
413 		case LINKLOCAL:
414 			link_local_start();
415 			break;
416 #endif
417 		default:
418 			break;
419 		}
420 
421 		break;
422 	}
423 
424 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
425 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
426 	defined(CONFIG_STATUS_LED)			&& \
427 	defined(STATUS_LED_RED)
428 	/*
429 	 * Echo the inverted link state to the fault LED.
430 	 */
431 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
432 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
433 	else
434 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
435 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
436 #endif /* CONFIG_MII, ... */
437 
438 	/*
439 	 *	Main packet reception loop.  Loop receiving packets until
440 	 *	someone sets `net_state' to a state that terminates.
441 	 */
442 	for (;;) {
443 		WATCHDOG_RESET();
444 #ifdef CONFIG_SHOW_ACTIVITY
445 		show_activity(1);
446 #endif
447 		/*
448 		 *	Check the ethernet for a new packet.  The ethernet
449 		 *	receive routine will process it.
450 		 */
451 		eth_rx();
452 
453 		/*
454 		 *	Abort if ctrl-c was pressed.
455 		 */
456 		if (ctrlc()) {
457 			/* cancel any ARP that may not have completed */
458 			NetArpWaitPacketIP = 0;
459 
460 			net_cleanup_loop();
461 			eth_halt();
462 			puts("\nAbort\n");
463 			goto done;
464 		}
465 
466 		ArpTimeoutCheck();
467 
468 		/*
469 		 *	Check for a timeout, and run the timeout handler
470 		 *	if we have one.
471 		 */
472 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
473 			thand_f *x;
474 
475 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
476 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
477 	defined(CONFIG_STATUS_LED)			&& \
478 	defined(STATUS_LED_RED)
479 			/*
480 			 * Echo the inverted link state to the fault LED.
481 			 */
482 			if (miiphy_link(eth_get_dev()->name,
483 				       CONFIG_SYS_FAULT_MII_ADDR)) {
484 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
485 			} else {
486 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
487 			}
488 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
489 #endif /* CONFIG_MII, ... */
490 			x = timeHandler;
491 			timeHandler = (thand_f *)0;
492 			(*x)();
493 		}
494 
495 
496 		switch (net_state) {
497 
498 		case NETLOOP_RESTART:
499 			NetRestarted = 1;
500 			goto restart;
501 
502 		case NETLOOP_SUCCESS:
503 			net_cleanup_loop();
504 			if (NetBootFileXferSize > 0) {
505 				char buf[20];
506 				printf("Bytes transferred = %ld (%lx hex)\n",
507 					NetBootFileXferSize,
508 					NetBootFileXferSize);
509 				sprintf(buf, "%lX", NetBootFileXferSize);
510 				setenv("filesize", buf);
511 
512 				sprintf(buf, "%lX", (unsigned long)load_addr);
513 				setenv("fileaddr", buf);
514 			}
515 			eth_halt();
516 			ret = NetBootFileXferSize;
517 			goto done;
518 
519 		case NETLOOP_FAIL:
520 			net_cleanup_loop();
521 			goto done;
522 
523 		case NETLOOP_CONTINUE:
524 			continue;
525 		}
526 	}
527 
528 done:
529 #ifdef CONFIG_CMD_TFTPPUT
530 	/* Clear out the handlers */
531 	net_set_udp_handler(NULL);
532 	net_set_icmp_handler(NULL);
533 #endif
534 	return ret;
535 }
536 
537 /**********************************************************************/
538 
539 static void
540 startAgainTimeout(void)
541 {
542 	net_set_state(NETLOOP_RESTART);
543 }
544 
545 void NetStartAgain(void)
546 {
547 	char *nretry;
548 	int retry_forever = 0;
549 	unsigned long retrycnt = 0;
550 
551 	nretry = getenv("netretry");
552 	if (nretry) {
553 		if (!strcmp(nretry, "yes"))
554 			retry_forever = 1;
555 		else if (!strcmp(nretry, "no"))
556 			retrycnt = 0;
557 		else if (!strcmp(nretry, "once"))
558 			retrycnt = 1;
559 		else
560 			retrycnt = simple_strtoul(nretry, NULL, 0);
561 	} else
562 		retry_forever = 1;
563 
564 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
565 		eth_halt();
566 		net_set_state(NETLOOP_FAIL);
567 		return;
568 	}
569 
570 	NetTryCount++;
571 
572 	eth_halt();
573 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
574 	eth_try_another(!NetRestarted);
575 #endif
576 	eth_init(gd->bd);
577 	if (NetRestartWrap) {
578 		NetRestartWrap = 0;
579 		if (NetDevExists) {
580 			NetSetTimeout(10000UL, startAgainTimeout);
581 			net_set_udp_handler(NULL);
582 		} else {
583 			net_set_state(NETLOOP_FAIL);
584 		}
585 	} else {
586 		net_set_state(NETLOOP_RESTART);
587 	}
588 }
589 
590 /**********************************************************************/
591 /*
592  *	Miscelaneous bits.
593  */
594 
595 static void dummy_handler(uchar *pkt, unsigned dport,
596 			IPaddr_t sip, unsigned sport,
597 			unsigned len)
598 {
599 }
600 
601 rxhand_f *net_get_udp_handler(void)
602 {
603 	return udp_packet_handler;
604 }
605 
606 void net_set_udp_handler(rxhand_f *f)
607 {
608 	if (f == NULL)
609 		udp_packet_handler = dummy_handler;
610 	else
611 		udp_packet_handler = f;
612 }
613 
614 rxhand_f *net_get_arp_handler(void)
615 {
616 	return arp_packet_handler;
617 }
618 
619 void net_set_arp_handler(rxhand_f *f)
620 {
621 	if (f == NULL)
622 		arp_packet_handler = dummy_handler;
623 	else
624 		arp_packet_handler = f;
625 }
626 
627 #ifdef CONFIG_CMD_TFTPPUT
628 void net_set_icmp_handler(rxhand_icmp_f *f)
629 {
630 	packet_icmp_handler = f;
631 }
632 #endif
633 
634 void
635 NetSetTimeout(ulong iv, thand_f *f)
636 {
637 	if (iv == 0) {
638 		timeHandler = (thand_f *)0;
639 	} else {
640 		timeHandler = f;
641 		timeStart = get_timer(0);
642 		timeDelta = iv;
643 	}
644 }
645 
646 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
647 		int payload_len)
648 {
649 	uchar *pkt;
650 	int eth_hdr_size;
651 	int pkt_hdr_size;
652 
653 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
654 	assert(NetTxPacket != NULL);
655 	if (NetTxPacket == NULL)
656 		return -1;
657 
658 	/* convert to new style broadcast */
659 	if (dest == 0)
660 		dest = 0xFFFFFFFF;
661 
662 	/* if broadcast, make the ether address a broadcast and don't do ARP */
663 	if (dest == 0xFFFFFFFF)
664 		ether = NetBcastAddr;
665 
666 	pkt = (uchar *)NetTxPacket;
667 
668 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
669 	pkt += eth_hdr_size;
670 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
671 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
672 
673 	/* if MAC address was not discovered yet, do an ARP request */
674 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
675 		debug("sending ARP for %pI4\n", &dest);
676 
677 		/* save the ip and eth addr for the packet to send after arp */
678 		NetArpWaitPacketIP = dest;
679 		NetArpWaitPacketMAC = ether;
680 
681 		/* size of the waiting packet */
682 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
683 
684 		/* and do the ARP request */
685 		NetArpWaitTry = 1;
686 		NetArpWaitTimerStart = get_timer(0);
687 		ArpRequest();
688 		return 1;	/* waiting */
689 	} else {
690 		debug("sending UDP to %pI4/%pM\n", &dest, ether);
691 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
692 		return 0;	/* transmitted */
693 	}
694 }
695 
696 #ifdef CONFIG_IP_DEFRAG
697 /*
698  * This function collects fragments in a single packet, according
699  * to the algorithm in RFC815. It returns NULL or the pointer to
700  * a complete packet, in static storage
701  */
702 #ifndef CONFIG_NET_MAXDEFRAG
703 #define CONFIG_NET_MAXDEFRAG 16384
704 #endif
705 /*
706  * MAXDEFRAG, above, is chosen in the config file and  is real data
707  * so we need to add the NFS overhead, which is more than TFTP.
708  * To use sizeof in the internal unnamed structures, we need a real
709  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
710  * The compiler doesn't complain nor allocates the actual structure
711  */
712 static struct rpc_t rpc_specimen;
713 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
714 
715 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
716 
717 /*
718  * this is the packet being assembled, either data or frag control.
719  * Fragments go by 8 bytes, so this union must be 8 bytes long
720  */
721 struct hole {
722 	/* first_byte is address of this structure */
723 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
724 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
725 	u16 prev_hole;	/* index of prev, 0 == none */
726 	u16 unused;
727 };
728 
729 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
730 {
731 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
732 	static u16 first_hole, total_len;
733 	struct hole *payload, *thisfrag, *h, *newh;
734 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
735 	uchar *indata = (uchar *)ip;
736 	int offset8, start, len, done = 0;
737 	u16 ip_off = ntohs(ip->ip_off);
738 
739 	/* payload starts after IP header, this fragment is in there */
740 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
741 	offset8 =  (ip_off & IP_OFFS);
742 	thisfrag = payload + offset8;
743 	start = offset8 * 8;
744 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
745 
746 	if (start + len > IP_MAXUDP) /* fragment extends too far */
747 		return NULL;
748 
749 	if (!total_len || localip->ip_id != ip->ip_id) {
750 		/* new (or different) packet, reset structs */
751 		total_len = 0xffff;
752 		payload[0].last_byte = ~0;
753 		payload[0].next_hole = 0;
754 		payload[0].prev_hole = 0;
755 		first_hole = 0;
756 		/* any IP header will work, copy the first we received */
757 		memcpy(localip, ip, IP_HDR_SIZE);
758 	}
759 
760 	/*
761 	 * What follows is the reassembly algorithm. We use the payload
762 	 * array as a linked list of hole descriptors, as each hole starts
763 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
764 	 * so it is represented as byte count, not as 8-byte blocks.
765 	 */
766 
767 	h = payload + first_hole;
768 	while (h->last_byte < start) {
769 		if (!h->next_hole) {
770 			/* no hole that far away */
771 			return NULL;
772 		}
773 		h = payload + h->next_hole;
774 	}
775 
776 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
777 	if (offset8 + ((len + 7) / 8) <= h - payload) {
778 		/* no overlap with holes (dup fragment?) */
779 		return NULL;
780 	}
781 
782 	if (!(ip_off & IP_FLAGS_MFRAG)) {
783 		/* no more fragmentss: truncate this (last) hole */
784 		total_len = start + len;
785 		h->last_byte = start + len;
786 	}
787 
788 	/*
789 	 * There is some overlap: fix the hole list. This code doesn't
790 	 * deal with a fragment that overlaps with two different holes
791 	 * (thus being a superset of a previously-received fragment).
792 	 */
793 
794 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
795 		/* complete overlap with hole: remove hole */
796 		if (!h->prev_hole && !h->next_hole) {
797 			/* last remaining hole */
798 			done = 1;
799 		} else if (!h->prev_hole) {
800 			/* first hole */
801 			first_hole = h->next_hole;
802 			payload[h->next_hole].prev_hole = 0;
803 		} else if (!h->next_hole) {
804 			/* last hole */
805 			payload[h->prev_hole].next_hole = 0;
806 		} else {
807 			/* in the middle of the list */
808 			payload[h->next_hole].prev_hole = h->prev_hole;
809 			payload[h->prev_hole].next_hole = h->next_hole;
810 		}
811 
812 	} else if (h->last_byte <= start + len) {
813 		/* overlaps with final part of the hole: shorten this hole */
814 		h->last_byte = start;
815 
816 	} else if (h >= thisfrag) {
817 		/* overlaps with initial part of the hole: move this hole */
818 		newh = thisfrag + (len / 8);
819 		*newh = *h;
820 		h = newh;
821 		if (h->next_hole)
822 			payload[h->next_hole].prev_hole = (h - payload);
823 		if (h->prev_hole)
824 			payload[h->prev_hole].next_hole = (h - payload);
825 		else
826 			first_hole = (h - payload);
827 
828 	} else {
829 		/* fragment sits in the middle: split the hole */
830 		newh = thisfrag + (len / 8);
831 		*newh = *h;
832 		h->last_byte = start;
833 		h->next_hole = (newh - payload);
834 		newh->prev_hole = (h - payload);
835 		if (newh->next_hole)
836 			payload[newh->next_hole].prev_hole = (newh - payload);
837 	}
838 
839 	/* finally copy this fragment and possibly return whole packet */
840 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
841 	if (!done)
842 		return NULL;
843 
844 	localip->ip_len = htons(total_len);
845 	*lenp = total_len + IP_HDR_SIZE;
846 	return localip;
847 }
848 
849 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
850 {
851 	u16 ip_off = ntohs(ip->ip_off);
852 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
853 		return ip; /* not a fragment */
854 	return __NetDefragment(ip, lenp);
855 }
856 
857 #else /* !CONFIG_IP_DEFRAG */
858 
859 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
860 {
861 	u16 ip_off = ntohs(ip->ip_off);
862 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
863 		return ip; /* not a fragment */
864 	return NULL;
865 }
866 #endif
867 
868 /**
869  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
870  * drop others.
871  *
872  * @parma ip	IP packet containing the ICMP
873  */
874 static void receive_icmp(struct ip_udp_hdr *ip, int len,
875 			IPaddr_t src_ip, struct ethernet_hdr *et)
876 {
877 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
878 
879 	switch (icmph->type) {
880 	case ICMP_REDIRECT:
881 		if (icmph->code != ICMP_REDIR_HOST)
882 			return;
883 		printf(" ICMP Host Redirect to %pI4 ",
884 			&icmph->un.gateway);
885 		break;
886 	default:
887 #if defined(CONFIG_CMD_PING)
888 		ping_receive(et, ip, len);
889 #endif
890 #ifdef CONFIG_CMD_TFTPPUT
891 		if (packet_icmp_handler)
892 			packet_icmp_handler(icmph->type, icmph->code,
893 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
894 				icmph->un.data, ntohs(ip->udp_len));
895 #endif
896 		break;
897 	}
898 }
899 
900 void
901 NetReceive(uchar *inpkt, int len)
902 {
903 	struct ethernet_hdr *et;
904 	struct ip_udp_hdr *ip;
905 	IPaddr_t dst_ip;
906 	IPaddr_t src_ip;
907 	int eth_proto;
908 #if defined(CONFIG_CMD_CDP)
909 	int iscdp;
910 #endif
911 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
912 
913 	debug("packet received\n");
914 
915 	NetRxPacket = inpkt;
916 	NetRxPacketLen = len;
917 	et = (struct ethernet_hdr *)inpkt;
918 
919 	/* too small packet? */
920 	if (len < ETHER_HDR_SIZE)
921 		return;
922 
923 #ifdef CONFIG_API
924 	if (push_packet) {
925 		(*push_packet)(inpkt, len);
926 		return;
927 	}
928 #endif
929 
930 #if defined(CONFIG_CMD_CDP)
931 	/* keep track if packet is CDP */
932 	iscdp = is_cdp_packet(et->et_dest);
933 #endif
934 
935 	myvlanid = ntohs(NetOurVLAN);
936 	if (myvlanid == (ushort)-1)
937 		myvlanid = VLAN_NONE;
938 	mynvlanid = ntohs(NetOurNativeVLAN);
939 	if (mynvlanid == (ushort)-1)
940 		mynvlanid = VLAN_NONE;
941 
942 	eth_proto = ntohs(et->et_protlen);
943 
944 	debug("packet received\n");
945 
946 	if (eth_proto < 1514) {
947 		struct e802_hdr *et802 = (struct e802_hdr *)et;
948 		/*
949 		 *	Got a 802.2 packet.  Check the other protocol field.
950 		 *	XXX VLAN over 802.2+SNAP not implemented!
951 		 */
952 		eth_proto = ntohs(et802->et_prot);
953 
954 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
955 		len -= E802_HDR_SIZE;
956 
957 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
958 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
959 		len -= ETHER_HDR_SIZE;
960 
961 	} else {			/* VLAN packet */
962 		struct vlan_ethernet_hdr *vet =
963 			(struct vlan_ethernet_hdr *)et;
964 
965 		debug("VLAN packet received\n");
966 
967 		/* too small packet? */
968 		if (len < VLAN_ETHER_HDR_SIZE)
969 			return;
970 
971 		/* if no VLAN active */
972 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
973 #if defined(CONFIG_CMD_CDP)
974 				&& iscdp == 0
975 #endif
976 				)
977 			return;
978 
979 		cti = ntohs(vet->vet_tag);
980 		vlanid = cti & VLAN_IDMASK;
981 		eth_proto = ntohs(vet->vet_type);
982 
983 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
984 		len -= VLAN_ETHER_HDR_SIZE;
985 	}
986 
987 	debug("Receive from protocol 0x%x\n", eth_proto);
988 
989 #if defined(CONFIG_CMD_CDP)
990 	if (iscdp) {
991 		cdp_receive((uchar *)ip, len);
992 		return;
993 	}
994 #endif
995 
996 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
997 		if (vlanid == VLAN_NONE)
998 			vlanid = (mynvlanid & VLAN_IDMASK);
999 		/* not matched? */
1000 		if (vlanid != (myvlanid & VLAN_IDMASK))
1001 			return;
1002 	}
1003 
1004 	switch (eth_proto) {
1005 
1006 	case PROT_ARP:
1007 		ArpReceive(et, ip, len);
1008 		break;
1009 
1010 #ifdef CONFIG_CMD_RARP
1011 	case PROT_RARP:
1012 		rarp_receive(ip, len);
1013 		break;
1014 #endif
1015 	case PROT_IP:
1016 		debug("Got IP\n");
1017 		/* Before we start poking the header, make sure it is there */
1018 		if (len < IP_UDP_HDR_SIZE) {
1019 			debug("len bad %d < %lu\n", len,
1020 				(ulong)IP_UDP_HDR_SIZE);
1021 			return;
1022 		}
1023 		/* Check the packet length */
1024 		if (len < ntohs(ip->ip_len)) {
1025 			printf("len bad %d < %d\n", len, ntohs(ip->ip_len));
1026 			return;
1027 		}
1028 		len = ntohs(ip->ip_len);
1029 		debug("len=%d, v=%02x\n", len, ip->ip_hl_v & 0xff);
1030 
1031 		/* Can't deal with anything except IPv4 */
1032 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1033 			return;
1034 		/* Can't deal with IP options (headers != 20 bytes) */
1035 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1036 			return;
1037 		/* Check the Checksum of the header */
1038 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1039 			puts("checksum bad\n");
1040 			return;
1041 		}
1042 		/* If it is not for us, ignore it */
1043 		dst_ip = NetReadIP(&ip->ip_dst);
1044 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1045 #ifdef CONFIG_MCAST_TFTP
1046 			if (Mcast_addr != dst_ip)
1047 #endif
1048 				return;
1049 		}
1050 		/* Read source IP address for later use */
1051 		src_ip = NetReadIP(&ip->ip_src);
1052 		/*
1053 		 * The function returns the unchanged packet if it's not
1054 		 * a fragment, and either the complete packet or NULL if
1055 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1056 		 */
1057 		ip = NetDefragment(ip, &len);
1058 		if (!ip)
1059 			return;
1060 		/*
1061 		 * watch for ICMP host redirects
1062 		 *
1063 		 * There is no real handler code (yet). We just watch
1064 		 * for ICMP host redirect messages. In case anybody
1065 		 * sees these messages: please contact me
1066 		 * (wd@denx.de), or - even better - send me the
1067 		 * necessary fixes :-)
1068 		 *
1069 		 * Note: in all cases where I have seen this so far
1070 		 * it was a problem with the router configuration,
1071 		 * for instance when a router was configured in the
1072 		 * BOOTP reply, but the TFTP server was on the same
1073 		 * subnet. So this is probably a warning that your
1074 		 * configuration might be wrong. But I'm not really
1075 		 * sure if there aren't any other situations.
1076 		 *
1077 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1078 		 * we send a tftp packet to a dead connection, or when
1079 		 * there is no server at the other end.
1080 		 */
1081 		if (ip->ip_p == IPPROTO_ICMP) {
1082 			receive_icmp(ip, len, src_ip, et);
1083 			return;
1084 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1085 			return;
1086 		}
1087 
1088 #ifdef CONFIG_UDP_CHECKSUM
1089 		if (ip->udp_xsum != 0) {
1090 			ulong   xsum;
1091 			ushort *sumptr;
1092 			ushort  sumlen;
1093 
1094 			xsum  = ip->ip_p;
1095 			xsum += (ntohs(ip->udp_len));
1096 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1097 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1098 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1099 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1100 
1101 			sumlen = ntohs(ip->udp_len);
1102 			sumptr = (ushort *) &(ip->udp_src);
1103 
1104 			while (sumlen > 1) {
1105 				ushort sumdata;
1106 
1107 				sumdata = *sumptr++;
1108 				xsum += ntohs(sumdata);
1109 				sumlen -= 2;
1110 			}
1111 			if (sumlen > 0) {
1112 				ushort sumdata;
1113 
1114 				sumdata = *(unsigned char *) sumptr;
1115 				sumdata = (sumdata << 8) & 0xff00;
1116 				xsum += sumdata;
1117 			}
1118 			while ((xsum >> 16) != 0) {
1119 				xsum = (xsum & 0x0000ffff) +
1120 				       ((xsum >> 16) & 0x0000ffff);
1121 			}
1122 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1123 				printf(" UDP wrong checksum %08lx %08x\n",
1124 					xsum, ntohs(ip->udp_xsum));
1125 				return;
1126 			}
1127 		}
1128 #endif
1129 
1130 
1131 #ifdef CONFIG_NETCONSOLE
1132 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1133 					ntohs(ip->udp_dst),
1134 					ntohs(ip->udp_src),
1135 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1136 #endif
1137 		/*
1138 		 *	IP header OK.  Pass the packet to the current handler.
1139 		 */
1140 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1141 				ntohs(ip->udp_dst),
1142 				src_ip,
1143 				ntohs(ip->udp_src),
1144 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1145 		break;
1146 	}
1147 }
1148 
1149 
1150 /**********************************************************************/
1151 
1152 static int net_check_prereq(enum proto_t protocol)
1153 {
1154 	switch (protocol) {
1155 		/* Fall through */
1156 #if defined(CONFIG_CMD_PING)
1157 	case PING:
1158 		if (NetPingIP == 0) {
1159 			puts("*** ERROR: ping address not given\n");
1160 			return 1;
1161 		}
1162 		goto common;
1163 #endif
1164 #if defined(CONFIG_CMD_SNTP)
1165 	case SNTP:
1166 		if (NetNtpServerIP == 0) {
1167 			puts("*** ERROR: NTP server address not given\n");
1168 			return 1;
1169 		}
1170 		goto common;
1171 #endif
1172 #if defined(CONFIG_CMD_DNS)
1173 	case DNS:
1174 		if (NetOurDNSIP == 0) {
1175 			puts("*** ERROR: DNS server address not given\n");
1176 			return 1;
1177 		}
1178 		goto common;
1179 #endif
1180 #if defined(CONFIG_CMD_NFS)
1181 	case NFS:
1182 #endif
1183 	case TFTPGET:
1184 	case TFTPPUT:
1185 		if (NetServerIP == 0) {
1186 			puts("*** ERROR: `serverip' not set\n");
1187 			return 1;
1188 		}
1189 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1190 	defined(CONFIG_CMD_DNS)
1191 common:
1192 #endif
1193 		/* Fall through */
1194 
1195 	case NETCONS:
1196 	case TFTPSRV:
1197 		if (NetOurIP == 0) {
1198 			puts("*** ERROR: `ipaddr' not set\n");
1199 			return 1;
1200 		}
1201 		/* Fall through */
1202 
1203 #ifdef CONFIG_CMD_RARP
1204 	case RARP:
1205 #endif
1206 	case BOOTP:
1207 	case CDP:
1208 	case DHCP:
1209 	case LINKLOCAL:
1210 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1211 			int num = eth_get_dev_index();
1212 
1213 			switch (num) {
1214 			case -1:
1215 				puts("*** ERROR: No ethernet found.\n");
1216 				return 1;
1217 			case 0:
1218 				puts("*** ERROR: `ethaddr' not set\n");
1219 				break;
1220 			default:
1221 				printf("*** ERROR: `eth%daddr' not set\n",
1222 					num);
1223 				break;
1224 			}
1225 
1226 			NetStartAgain();
1227 			return 2;
1228 		}
1229 		/* Fall through */
1230 	default:
1231 		return 0;
1232 	}
1233 	return 0;		/* OK */
1234 }
1235 /**********************************************************************/
1236 
1237 int
1238 NetCksumOk(uchar *ptr, int len)
1239 {
1240 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1241 }
1242 
1243 
1244 unsigned
1245 NetCksum(uchar *ptr, int len)
1246 {
1247 	ulong	xsum;
1248 	ushort *p = (ushort *)ptr;
1249 
1250 	xsum = 0;
1251 	while (len-- > 0)
1252 		xsum += *p++;
1253 	xsum = (xsum & 0xffff) + (xsum >> 16);
1254 	xsum = (xsum & 0xffff) + (xsum >> 16);
1255 	return xsum & 0xffff;
1256 }
1257 
1258 int
1259 NetEthHdrSize(void)
1260 {
1261 	ushort myvlanid;
1262 
1263 	myvlanid = ntohs(NetOurVLAN);
1264 	if (myvlanid == (ushort)-1)
1265 		myvlanid = VLAN_NONE;
1266 
1267 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1268 		VLAN_ETHER_HDR_SIZE;
1269 }
1270 
1271 int
1272 NetSetEther(uchar *xet, uchar * addr, uint prot)
1273 {
1274 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1275 	ushort myvlanid;
1276 
1277 	myvlanid = ntohs(NetOurVLAN);
1278 	if (myvlanid == (ushort)-1)
1279 		myvlanid = VLAN_NONE;
1280 
1281 	memcpy(et->et_dest, addr, 6);
1282 	memcpy(et->et_src, NetOurEther, 6);
1283 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1284 		et->et_protlen = htons(prot);
1285 		return ETHER_HDR_SIZE;
1286 	} else {
1287 		struct vlan_ethernet_hdr *vet =
1288 			(struct vlan_ethernet_hdr *)xet;
1289 
1290 		vet->vet_vlan_type = htons(PROT_VLAN);
1291 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1292 		vet->vet_type = htons(prot);
1293 		return VLAN_ETHER_HDR_SIZE;
1294 	}
1295 }
1296 
1297 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1298 {
1299 	ushort protlen;
1300 
1301 	memcpy(et->et_dest, addr, 6);
1302 	memcpy(et->et_src, NetOurEther, 6);
1303 	protlen = ntohs(et->et_protlen);
1304 	if (protlen == PROT_VLAN) {
1305 		struct vlan_ethernet_hdr *vet =
1306 			(struct vlan_ethernet_hdr *)et;
1307 		vet->vet_type = htons(prot);
1308 		return VLAN_ETHER_HDR_SIZE;
1309 	} else if (protlen > 1514) {
1310 		et->et_protlen = htons(prot);
1311 		return ETHER_HDR_SIZE;
1312 	} else {
1313 		/* 802.2 + SNAP */
1314 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1315 		et802->et_prot = htons(prot);
1316 		return E802_HDR_SIZE;
1317 	}
1318 }
1319 
1320 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1321 {
1322 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1323 
1324 	/*
1325 	 *	Construct an IP header.
1326 	 */
1327 	/* IP_HDR_SIZE / 4 (not including UDP) */
1328 	ip->ip_hl_v  = 0x45;
1329 	ip->ip_tos   = 0;
1330 	ip->ip_len   = htons(IP_HDR_SIZE);
1331 	ip->ip_id    = htons(NetIPID++);
1332 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1333 	ip->ip_ttl   = 255;
1334 	ip->ip_sum   = 0;
1335 	/* already in network byte order */
1336 	NetCopyIP((void *)&ip->ip_src, &source);
1337 	/* already in network byte order */
1338 	NetCopyIP((void *)&ip->ip_dst, &dest);
1339 }
1340 
1341 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1342 			int len)
1343 {
1344 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1345 
1346 	/*
1347 	 *	If the data is an odd number of bytes, zero the
1348 	 *	byte after the last byte so that the checksum
1349 	 *	will work.
1350 	 */
1351 	if (len & 1)
1352 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1353 
1354 	net_set_ip_header(pkt, dest, NetOurIP);
1355 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1356 	ip->ip_p     = IPPROTO_UDP;
1357 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1358 
1359 	ip->udp_src  = htons(sport);
1360 	ip->udp_dst  = htons(dport);
1361 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1362 	ip->udp_xsum = 0;
1363 }
1364 
1365 void copy_filename(char *dst, const char *src, int size)
1366 {
1367 	if (*src && (*src == '"')) {
1368 		++src;
1369 		--size;
1370 	}
1371 
1372 	while ((--size > 0) && *src && (*src != '"'))
1373 		*dst++ = *src++;
1374 	*dst = '\0';
1375 }
1376 
1377 #if	defined(CONFIG_CMD_NFS)		|| \
1378 	defined(CONFIG_CMD_SNTP)	|| \
1379 	defined(CONFIG_CMD_DNS)
1380 /*
1381  * make port a little random (1024-17407)
1382  * This keeps the math somewhat trivial to compute, and seems to work with
1383  * all supported protocols/clients/servers
1384  */
1385 unsigned int random_port(void)
1386 {
1387 	return 1024 + (get_timer(0) % 0x4000);
1388 }
1389 #endif
1390 
1391 void ip_to_string(IPaddr_t x, char *s)
1392 {
1393 	x = ntohl(x);
1394 	sprintf(s, "%d.%d.%d.%d",
1395 		(int) ((x >> 24) & 0xff),
1396 		(int) ((x >> 16) & 0xff),
1397 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1398 	);
1399 }
1400 
1401 void VLAN_to_string(ushort x, char *s)
1402 {
1403 	x = ntohs(x);
1404 
1405 	if (x == (ushort)-1)
1406 		x = VLAN_NONE;
1407 
1408 	if (x == VLAN_NONE)
1409 		strcpy(s, "none");
1410 	else
1411 		sprintf(s, "%d", x & VLAN_IDMASK);
1412 }
1413 
1414 ushort string_to_VLAN(const char *s)
1415 {
1416 	ushort id;
1417 
1418 	if (s == NULL)
1419 		return htons(VLAN_NONE);
1420 
1421 	if (*s < '0' || *s > '9')
1422 		id = VLAN_NONE;
1423 	else
1424 		id = (ushort)simple_strtoul(s, NULL, 10);
1425 
1426 	return htons(id);
1427 }
1428 
1429 ushort getenv_VLAN(char *var)
1430 {
1431 	return string_to_VLAN(getenv(var));
1432 }
1433