xref: /openbmc/u-boot/net/net.c (revision 63495ad7)
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 <environment.h>
86 #include <net.h>
87 #if defined(CONFIG_STATUS_LED)
88 #include <miiphy.h>
89 #include <status_led.h>
90 #endif
91 #include <watchdog.h>
92 #include <linux/compiler.h>
93 #include "arp.h"
94 #include "bootp.h"
95 #include "cdp.h"
96 #if defined(CONFIG_CMD_DNS)
97 #include "dns.h"
98 #endif
99 #include "link_local.h"
100 #include "nfs.h"
101 #include "ping.h"
102 #include "rarp.h"
103 #if defined(CONFIG_CMD_SNTP)
104 #include "sntp.h"
105 #endif
106 #include "tftp.h"
107 
108 DECLARE_GLOBAL_DATA_PTR;
109 
110 /** BOOTP EXTENTIONS **/
111 
112 /* Our subnet mask (0=unknown) */
113 IPaddr_t	NetOurSubnetMask;
114 /* Our gateways IP address */
115 IPaddr_t	NetOurGatewayIP;
116 /* Our DNS IP address */
117 IPaddr_t	NetOurDNSIP;
118 #if defined(CONFIG_BOOTP_DNS2)
119 /* Our 2nd DNS IP address */
120 IPaddr_t	NetOurDNS2IP;
121 #endif
122 /* Our NIS domain */
123 char		NetOurNISDomain[32] = {0,};
124 /* Our hostname */
125 char		NetOurHostName[32] = {0,};
126 /* Our bootpath */
127 char		NetOurRootPath[64] = {0,};
128 /* Our bootfile size in blocks */
129 ushort		NetBootFileSize;
130 
131 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
132 IPaddr_t Mcast_addr;
133 #endif
134 
135 /** END OF BOOTP EXTENTIONS **/
136 
137 /* The actual transferred size of the bootfile (in bytes) */
138 ulong		NetBootFileXferSize;
139 /* Our ethernet address */
140 uchar		NetOurEther[6];
141 /* Boot server enet address */
142 uchar		NetServerEther[6];
143 /* Our IP addr (0 = unknown) */
144 IPaddr_t	NetOurIP;
145 /* Server IP addr (0 = unknown) */
146 IPaddr_t	NetServerIP;
147 /* Current receive packet */
148 uchar *NetRxPacket;
149 /* Current rx packet length */
150 int		NetRxPacketLen;
151 /* IP packet ID */
152 unsigned	NetIPID;
153 /* Ethernet bcast address */
154 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
155 uchar		NetEtherNullAddr[6];
156 #ifdef CONFIG_API
157 void		(*push_packet)(void *, int len) = 0;
158 #endif
159 /* Network loop state */
160 enum net_loop_state net_state;
161 /* Tried all network devices */
162 int		NetRestartWrap;
163 /* Network loop restarted */
164 static int	NetRestarted;
165 /* At least one device configured */
166 static int	NetDevExists;
167 
168 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
169 /* default is without VLAN */
170 ushort		NetOurVLAN = 0xFFFF;
171 /* ditto */
172 ushort		NetOurNativeVLAN = 0xFFFF;
173 
174 /* Boot File name */
175 char		BootFile[128];
176 
177 #if defined(CONFIG_CMD_SNTP)
178 /* NTP server IP address */
179 IPaddr_t	NetNtpServerIP;
180 /* offset time from UTC */
181 int		NetTimeOffset;
182 #endif
183 
184 static uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
185 
186 /* Receive packet */
187 uchar *NetRxPackets[PKTBUFSRX];
188 
189 /* Current UDP RX packet handler */
190 static rxhand_f *udp_packet_handler;
191 /* Current ARP RX packet handler */
192 static rxhand_f *arp_packet_handler;
193 #ifdef CONFIG_CMD_TFTPPUT
194 /* Current ICMP rx handler */
195 static rxhand_icmp_f *packet_icmp_handler;
196 #endif
197 /* Current timeout handler */
198 static thand_f *timeHandler;
199 /* Time base value */
200 static ulong	timeStart;
201 /* Current timeout value */
202 static ulong	timeDelta;
203 /* THE transmit packet */
204 uchar *NetTxPacket;
205 
206 static int net_check_prereq(enum proto_t protocol);
207 
208 static int NetTryCount;
209 
210 /**********************************************************************/
211 
212 static int on_bootfile(const char *name, const char *value, enum env_op op,
213 	int flags)
214 {
215 	switch (op) {
216 	case env_op_create:
217 	case env_op_overwrite:
218 		copy_filename(BootFile, value, sizeof(BootFile));
219 		break;
220 	default:
221 		break;
222 	}
223 
224 	return 0;
225 }
226 U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
227 
228 /*
229  * Check if autoload is enabled. If so, use either NFS or TFTP to download
230  * the boot file.
231  */
232 void net_auto_load(void)
233 {
234 #if defined(CONFIG_CMD_NFS)
235 	const char *s = getenv("autoload");
236 
237 	if (s != NULL && strcmp(s, "NFS") == 0) {
238 		/*
239 		 * Use NFS to load the bootfile.
240 		 */
241 		NfsStart();
242 		return;
243 	}
244 #endif
245 	if (getenv_yesno("autoload") == 0) {
246 		/*
247 		 * Just use BOOTP/RARP to configure system;
248 		 * Do not use TFTP to load the bootfile.
249 		 */
250 		net_set_state(NETLOOP_SUCCESS);
251 		return;
252 	}
253 	TftpStart(TFTPGET);
254 }
255 
256 static void NetInitLoop(void)
257 {
258 	static int env_changed_id;
259 	int env_id = get_env_id();
260 
261 	/* update only when the environment has changed */
262 	if (env_changed_id != env_id) {
263 		NetOurIP = getenv_IPaddr("ipaddr");
264 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
265 		NetOurSubnetMask = getenv_IPaddr("netmask");
266 		NetServerIP = getenv_IPaddr("serverip");
267 		NetOurNativeVLAN = getenv_VLAN("nvlan");
268 		NetOurVLAN = getenv_VLAN("vlan");
269 #if defined(CONFIG_CMD_DNS)
270 		NetOurDNSIP = getenv_IPaddr("dnsip");
271 #endif
272 		env_changed_id = env_id;
273 	}
274 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
275 
276 	return;
277 }
278 
279 static void net_clear_handlers(void)
280 {
281 	net_set_udp_handler(NULL);
282 	net_set_arp_handler(NULL);
283 	NetSetTimeout(0, NULL);
284 }
285 
286 static void net_cleanup_loop(void)
287 {
288 	net_clear_handlers();
289 }
290 
291 void net_init(void)
292 {
293 	static int first_call = 1;
294 
295 	if (first_call) {
296 		/*
297 		 *	Setup packet buffers, aligned correctly.
298 		 */
299 		int i;
300 
301 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
302 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
303 		for (i = 0; i < PKTBUFSRX; i++)
304 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
305 
306 		ArpInit();
307 		net_clear_handlers();
308 
309 		/* Only need to setup buffer pointers once. */
310 		first_call = 0;
311 	}
312 
313 	NetInitLoop();
314 }
315 
316 /**********************************************************************/
317 /*
318  *	Main network processing loop.
319  */
320 
321 int NetLoop(enum proto_t protocol)
322 {
323 	bd_t *bd = gd->bd;
324 	int ret = -1;
325 
326 	NetRestarted = 0;
327 	NetDevExists = 0;
328 	NetTryCount = 1;
329 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
330 
331 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
332 	net_init();
333 	if (eth_is_on_demand_init() || protocol != NETCONS) {
334 		eth_halt();
335 		eth_set_current();
336 		if (eth_init(bd) < 0) {
337 			eth_halt();
338 			return -1;
339 		}
340 	} else
341 		eth_init_state_only(bd);
342 
343 restart:
344 	net_set_state(NETLOOP_CONTINUE);
345 
346 	/*
347 	 *	Start the ball rolling with the given start function.  From
348 	 *	here on, this code is a state machine driven by received
349 	 *	packets and timer events.
350 	 */
351 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
352 	NetInitLoop();
353 
354 	switch (net_check_prereq(protocol)) {
355 	case 1:
356 		/* network not configured */
357 		eth_halt();
358 		return -1;
359 
360 	case 2:
361 		/* network device not configured */
362 		break;
363 
364 	case 0:
365 		NetDevExists = 1;
366 		NetBootFileXferSize = 0;
367 		switch (protocol) {
368 		case TFTPGET:
369 #ifdef CONFIG_CMD_TFTPPUT
370 		case TFTPPUT:
371 #endif
372 			/* always use ARP to get server ethernet address */
373 			TftpStart(protocol);
374 			break;
375 #ifdef CONFIG_CMD_TFTPSRV
376 		case TFTPSRV:
377 			TftpStartServer();
378 			break;
379 #endif
380 #if defined(CONFIG_CMD_DHCP)
381 		case DHCP:
382 			BootpTry = 0;
383 			NetOurIP = 0;
384 			DhcpRequest();		/* Basically same as BOOTP */
385 			break;
386 #endif
387 
388 		case BOOTP:
389 			BootpTry = 0;
390 			NetOurIP = 0;
391 			BootpRequest();
392 			break;
393 
394 #if defined(CONFIG_CMD_RARP)
395 		case RARP:
396 			RarpTry = 0;
397 			NetOurIP = 0;
398 			RarpRequest();
399 			break;
400 #endif
401 #if defined(CONFIG_CMD_PING)
402 		case PING:
403 			ping_start();
404 			break;
405 #endif
406 #if defined(CONFIG_CMD_NFS)
407 		case NFS:
408 			NfsStart();
409 			break;
410 #endif
411 #if defined(CONFIG_CMD_CDP)
412 		case CDP:
413 			CDPStart();
414 			break;
415 #endif
416 #ifdef CONFIG_NETCONSOLE
417 		case NETCONS:
418 			NcStart();
419 			break;
420 #endif
421 #if defined(CONFIG_CMD_SNTP)
422 		case SNTP:
423 			SntpStart();
424 			break;
425 #endif
426 #if defined(CONFIG_CMD_DNS)
427 		case DNS:
428 			DnsStart();
429 			break;
430 #endif
431 #if defined(CONFIG_CMD_LINK_LOCAL)
432 		case LINKLOCAL:
433 			link_local_start();
434 			break;
435 #endif
436 		default:
437 			break;
438 		}
439 
440 		break;
441 	}
442 
443 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
444 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
445 	defined(CONFIG_STATUS_LED)			&& \
446 	defined(STATUS_LED_RED)
447 	/*
448 	 * Echo the inverted link state to the fault LED.
449 	 */
450 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
451 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
452 	else
453 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
454 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
455 #endif /* CONFIG_MII, ... */
456 
457 	/*
458 	 *	Main packet reception loop.  Loop receiving packets until
459 	 *	someone sets `net_state' to a state that terminates.
460 	 */
461 	for (;;) {
462 		WATCHDOG_RESET();
463 #ifdef CONFIG_SHOW_ACTIVITY
464 		show_activity(1);
465 #endif
466 		/*
467 		 *	Check the ethernet for a new packet.  The ethernet
468 		 *	receive routine will process it.
469 		 */
470 		eth_rx();
471 
472 		/*
473 		 *	Abort if ctrl-c was pressed.
474 		 */
475 		if (ctrlc()) {
476 			/* cancel any ARP that may not have completed */
477 			NetArpWaitPacketIP = 0;
478 
479 			net_cleanup_loop();
480 			eth_halt();
481 			/* Invalidate the last protocol */
482 			eth_set_last_protocol(BOOTP);
483 
484 			puts("\nAbort\n");
485 			/* include a debug print as well incase the debug
486 			   messages are directed to stderr */
487 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
488 			goto done;
489 		}
490 
491 		ArpTimeoutCheck();
492 
493 		/*
494 		 *	Check for a timeout, and run the timeout handler
495 		 *	if we have one.
496 		 */
497 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
498 			thand_f *x;
499 
500 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
501 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
502 	defined(CONFIG_STATUS_LED)			&& \
503 	defined(STATUS_LED_RED)
504 			/*
505 			 * Echo the inverted link state to the fault LED.
506 			 */
507 			if (miiphy_link(eth_get_dev()->name,
508 				       CONFIG_SYS_FAULT_MII_ADDR)) {
509 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
510 			} else {
511 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
512 			}
513 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
514 #endif /* CONFIG_MII, ... */
515 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
516 			x = timeHandler;
517 			timeHandler = (thand_f *)0;
518 			(*x)();
519 		}
520 
521 
522 		switch (net_state) {
523 
524 		case NETLOOP_RESTART:
525 			NetRestarted = 1;
526 			goto restart;
527 
528 		case NETLOOP_SUCCESS:
529 			net_cleanup_loop();
530 			if (NetBootFileXferSize > 0) {
531 				printf("Bytes transferred = %ld (%lx hex)\n",
532 					NetBootFileXferSize,
533 					NetBootFileXferSize);
534 				setenv_hex("filesize", NetBootFileXferSize);
535 				setenv_hex("fileaddr", load_addr);
536 			}
537 			if (protocol != NETCONS)
538 				eth_halt();
539 			else
540 				eth_halt_state_only();
541 
542 			eth_set_last_protocol(protocol);
543 
544 			ret = NetBootFileXferSize;
545 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
546 			goto done;
547 
548 		case NETLOOP_FAIL:
549 			net_cleanup_loop();
550 			/* Invalidate the last protocol */
551 			eth_set_last_protocol(BOOTP);
552 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
553 			goto done;
554 
555 		case NETLOOP_CONTINUE:
556 			continue;
557 		}
558 	}
559 
560 done:
561 #ifdef CONFIG_CMD_TFTPPUT
562 	/* Clear out the handlers */
563 	net_set_udp_handler(NULL);
564 	net_set_icmp_handler(NULL);
565 #endif
566 	return ret;
567 }
568 
569 /**********************************************************************/
570 
571 static void
572 startAgainTimeout(void)
573 {
574 	net_set_state(NETLOOP_RESTART);
575 }
576 
577 void NetStartAgain(void)
578 {
579 	char *nretry;
580 	int retry_forever = 0;
581 	unsigned long retrycnt = 0;
582 
583 	nretry = getenv("netretry");
584 	if (nretry) {
585 		if (!strcmp(nretry, "yes"))
586 			retry_forever = 1;
587 		else if (!strcmp(nretry, "no"))
588 			retrycnt = 0;
589 		else if (!strcmp(nretry, "once"))
590 			retrycnt = 1;
591 		else
592 			retrycnt = simple_strtoul(nretry, NULL, 0);
593 	} else
594 		retry_forever = 1;
595 
596 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
597 		eth_halt();
598 		net_set_state(NETLOOP_FAIL);
599 		return;
600 	}
601 
602 	NetTryCount++;
603 
604 	eth_halt();
605 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
606 	eth_try_another(!NetRestarted);
607 #endif
608 	eth_init(gd->bd);
609 	if (NetRestartWrap) {
610 		NetRestartWrap = 0;
611 		if (NetDevExists) {
612 			NetSetTimeout(10000UL, startAgainTimeout);
613 			net_set_udp_handler(NULL);
614 		} else {
615 			net_set_state(NETLOOP_FAIL);
616 		}
617 	} else {
618 		net_set_state(NETLOOP_RESTART);
619 	}
620 }
621 
622 /**********************************************************************/
623 /*
624  *	Miscelaneous bits.
625  */
626 
627 static void dummy_handler(uchar *pkt, unsigned dport,
628 			IPaddr_t sip, unsigned sport,
629 			unsigned len)
630 {
631 }
632 
633 rxhand_f *net_get_udp_handler(void)
634 {
635 	return udp_packet_handler;
636 }
637 
638 void net_set_udp_handler(rxhand_f *f)
639 {
640 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
641 	if (f == NULL)
642 		udp_packet_handler = dummy_handler;
643 	else
644 		udp_packet_handler = f;
645 }
646 
647 rxhand_f *net_get_arp_handler(void)
648 {
649 	return arp_packet_handler;
650 }
651 
652 void net_set_arp_handler(rxhand_f *f)
653 {
654 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
655 	if (f == NULL)
656 		arp_packet_handler = dummy_handler;
657 	else
658 		arp_packet_handler = f;
659 }
660 
661 #ifdef CONFIG_CMD_TFTPPUT
662 void net_set_icmp_handler(rxhand_icmp_f *f)
663 {
664 	packet_icmp_handler = f;
665 }
666 #endif
667 
668 void
669 NetSetTimeout(ulong iv, thand_f *f)
670 {
671 	if (iv == 0) {
672 		debug_cond(DEBUG_INT_STATE,
673 			"--- NetLoop timeout handler cancelled\n");
674 		timeHandler = (thand_f *)0;
675 	} else {
676 		debug_cond(DEBUG_INT_STATE,
677 			"--- NetLoop timeout handler set (%p)\n", f);
678 		timeHandler = f;
679 		timeStart = get_timer(0);
680 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
681 	}
682 }
683 
684 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
685 		int payload_len)
686 {
687 	uchar *pkt;
688 	int eth_hdr_size;
689 	int pkt_hdr_size;
690 
691 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
692 	assert(NetTxPacket != NULL);
693 	if (NetTxPacket == NULL)
694 		return -1;
695 
696 	/* convert to new style broadcast */
697 	if (dest == 0)
698 		dest = 0xFFFFFFFF;
699 
700 	/* if broadcast, make the ether address a broadcast and don't do ARP */
701 	if (dest == 0xFFFFFFFF)
702 		ether = NetBcastAddr;
703 
704 	pkt = (uchar *)NetTxPacket;
705 
706 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
707 	pkt += eth_hdr_size;
708 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
709 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
710 
711 	/* if MAC address was not discovered yet, do an ARP request */
712 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
713 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
714 
715 		/* save the ip and eth addr for the packet to send after arp */
716 		NetArpWaitPacketIP = dest;
717 		NetArpWaitPacketMAC = ether;
718 
719 		/* size of the waiting packet */
720 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
721 
722 		/* and do the ARP request */
723 		NetArpWaitTry = 1;
724 		NetArpWaitTimerStart = get_timer(0);
725 		ArpRequest();
726 		return 1;	/* waiting */
727 	} else {
728 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
729 			&dest, ether);
730 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
731 		return 0;	/* transmitted */
732 	}
733 }
734 
735 #ifdef CONFIG_IP_DEFRAG
736 /*
737  * This function collects fragments in a single packet, according
738  * to the algorithm in RFC815. It returns NULL or the pointer to
739  * a complete packet, in static storage
740  */
741 #ifndef CONFIG_NET_MAXDEFRAG
742 #define CONFIG_NET_MAXDEFRAG 16384
743 #endif
744 /*
745  * MAXDEFRAG, above, is chosen in the config file and  is real data
746  * so we need to add the NFS overhead, which is more than TFTP.
747  * To use sizeof in the internal unnamed structures, we need a real
748  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
749  * The compiler doesn't complain nor allocates the actual structure
750  */
751 static struct rpc_t rpc_specimen;
752 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
753 
754 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
755 
756 /*
757  * this is the packet being assembled, either data or frag control.
758  * Fragments go by 8 bytes, so this union must be 8 bytes long
759  */
760 struct hole {
761 	/* first_byte is address of this structure */
762 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
763 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
764 	u16 prev_hole;	/* index of prev, 0 == none */
765 	u16 unused;
766 };
767 
768 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
769 {
770 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
771 	static u16 first_hole, total_len;
772 	struct hole *payload, *thisfrag, *h, *newh;
773 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
774 	uchar *indata = (uchar *)ip;
775 	int offset8, start, len, done = 0;
776 	u16 ip_off = ntohs(ip->ip_off);
777 
778 	/* payload starts after IP header, this fragment is in there */
779 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
780 	offset8 =  (ip_off & IP_OFFS);
781 	thisfrag = payload + offset8;
782 	start = offset8 * 8;
783 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
784 
785 	if (start + len > IP_MAXUDP) /* fragment extends too far */
786 		return NULL;
787 
788 	if (!total_len || localip->ip_id != ip->ip_id) {
789 		/* new (or different) packet, reset structs */
790 		total_len = 0xffff;
791 		payload[0].last_byte = ~0;
792 		payload[0].next_hole = 0;
793 		payload[0].prev_hole = 0;
794 		first_hole = 0;
795 		/* any IP header will work, copy the first we received */
796 		memcpy(localip, ip, IP_HDR_SIZE);
797 	}
798 
799 	/*
800 	 * What follows is the reassembly algorithm. We use the payload
801 	 * array as a linked list of hole descriptors, as each hole starts
802 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
803 	 * so it is represented as byte count, not as 8-byte blocks.
804 	 */
805 
806 	h = payload + first_hole;
807 	while (h->last_byte < start) {
808 		if (!h->next_hole) {
809 			/* no hole that far away */
810 			return NULL;
811 		}
812 		h = payload + h->next_hole;
813 	}
814 
815 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
816 	if (offset8 + ((len + 7) / 8) <= h - payload) {
817 		/* no overlap with holes (dup fragment?) */
818 		return NULL;
819 	}
820 
821 	if (!(ip_off & IP_FLAGS_MFRAG)) {
822 		/* no more fragmentss: truncate this (last) hole */
823 		total_len = start + len;
824 		h->last_byte = start + len;
825 	}
826 
827 	/*
828 	 * There is some overlap: fix the hole list. This code doesn't
829 	 * deal with a fragment that overlaps with two different holes
830 	 * (thus being a superset of a previously-received fragment).
831 	 */
832 
833 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
834 		/* complete overlap with hole: remove hole */
835 		if (!h->prev_hole && !h->next_hole) {
836 			/* last remaining hole */
837 			done = 1;
838 		} else if (!h->prev_hole) {
839 			/* first hole */
840 			first_hole = h->next_hole;
841 			payload[h->next_hole].prev_hole = 0;
842 		} else if (!h->next_hole) {
843 			/* last hole */
844 			payload[h->prev_hole].next_hole = 0;
845 		} else {
846 			/* in the middle of the list */
847 			payload[h->next_hole].prev_hole = h->prev_hole;
848 			payload[h->prev_hole].next_hole = h->next_hole;
849 		}
850 
851 	} else if (h->last_byte <= start + len) {
852 		/* overlaps with final part of the hole: shorten this hole */
853 		h->last_byte = start;
854 
855 	} else if (h >= thisfrag) {
856 		/* overlaps with initial part of the hole: move this hole */
857 		newh = thisfrag + (len / 8);
858 		*newh = *h;
859 		h = newh;
860 		if (h->next_hole)
861 			payload[h->next_hole].prev_hole = (h - payload);
862 		if (h->prev_hole)
863 			payload[h->prev_hole].next_hole = (h - payload);
864 		else
865 			first_hole = (h - payload);
866 
867 	} else {
868 		/* fragment sits in the middle: split the hole */
869 		newh = thisfrag + (len / 8);
870 		*newh = *h;
871 		h->last_byte = start;
872 		h->next_hole = (newh - payload);
873 		newh->prev_hole = (h - payload);
874 		if (newh->next_hole)
875 			payload[newh->next_hole].prev_hole = (newh - payload);
876 	}
877 
878 	/* finally copy this fragment and possibly return whole packet */
879 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
880 	if (!done)
881 		return NULL;
882 
883 	localip->ip_len = htons(total_len);
884 	*lenp = total_len + IP_HDR_SIZE;
885 	return localip;
886 }
887 
888 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
889 {
890 	u16 ip_off = ntohs(ip->ip_off);
891 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
892 		return ip; /* not a fragment */
893 	return __NetDefragment(ip, lenp);
894 }
895 
896 #else /* !CONFIG_IP_DEFRAG */
897 
898 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
899 {
900 	u16 ip_off = ntohs(ip->ip_off);
901 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
902 		return ip; /* not a fragment */
903 	return NULL;
904 }
905 #endif
906 
907 /**
908  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
909  * drop others.
910  *
911  * @parma ip	IP packet containing the ICMP
912  */
913 static void receive_icmp(struct ip_udp_hdr *ip, int len,
914 			IPaddr_t src_ip, struct ethernet_hdr *et)
915 {
916 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
917 
918 	switch (icmph->type) {
919 	case ICMP_REDIRECT:
920 		if (icmph->code != ICMP_REDIR_HOST)
921 			return;
922 		printf(" ICMP Host Redirect to %pI4 ",
923 			&icmph->un.gateway);
924 		break;
925 	default:
926 #if defined(CONFIG_CMD_PING)
927 		ping_receive(et, ip, len);
928 #endif
929 #ifdef CONFIG_CMD_TFTPPUT
930 		if (packet_icmp_handler)
931 			packet_icmp_handler(icmph->type, icmph->code,
932 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
933 				icmph->un.data, ntohs(ip->udp_len));
934 #endif
935 		break;
936 	}
937 }
938 
939 void
940 NetReceive(uchar *inpkt, int len)
941 {
942 	struct ethernet_hdr *et;
943 	struct ip_udp_hdr *ip;
944 	IPaddr_t dst_ip;
945 	IPaddr_t src_ip;
946 	int eth_proto;
947 #if defined(CONFIG_CMD_CDP)
948 	int iscdp;
949 #endif
950 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
951 
952 	debug_cond(DEBUG_NET_PKT, "packet received\n");
953 
954 	NetRxPacket = inpkt;
955 	NetRxPacketLen = len;
956 	et = (struct ethernet_hdr *)inpkt;
957 
958 	/* too small packet? */
959 	if (len < ETHER_HDR_SIZE)
960 		return;
961 
962 #ifdef CONFIG_API
963 	if (push_packet) {
964 		(*push_packet)(inpkt, len);
965 		return;
966 	}
967 #endif
968 
969 #if defined(CONFIG_CMD_CDP)
970 	/* keep track if packet is CDP */
971 	iscdp = is_cdp_packet(et->et_dest);
972 #endif
973 
974 	myvlanid = ntohs(NetOurVLAN);
975 	if (myvlanid == (ushort)-1)
976 		myvlanid = VLAN_NONE;
977 	mynvlanid = ntohs(NetOurNativeVLAN);
978 	if (mynvlanid == (ushort)-1)
979 		mynvlanid = VLAN_NONE;
980 
981 	eth_proto = ntohs(et->et_protlen);
982 
983 	if (eth_proto < 1514) {
984 		struct e802_hdr *et802 = (struct e802_hdr *)et;
985 		/*
986 		 *	Got a 802.2 packet.  Check the other protocol field.
987 		 *	XXX VLAN over 802.2+SNAP not implemented!
988 		 */
989 		eth_proto = ntohs(et802->et_prot);
990 
991 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
992 		len -= E802_HDR_SIZE;
993 
994 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
995 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
996 		len -= ETHER_HDR_SIZE;
997 
998 	} else {			/* VLAN packet */
999 		struct vlan_ethernet_hdr *vet =
1000 			(struct vlan_ethernet_hdr *)et;
1001 
1002 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1003 
1004 		/* too small packet? */
1005 		if (len < VLAN_ETHER_HDR_SIZE)
1006 			return;
1007 
1008 		/* if no VLAN active */
1009 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1010 #if defined(CONFIG_CMD_CDP)
1011 				&& iscdp == 0
1012 #endif
1013 				)
1014 			return;
1015 
1016 		cti = ntohs(vet->vet_tag);
1017 		vlanid = cti & VLAN_IDMASK;
1018 		eth_proto = ntohs(vet->vet_type);
1019 
1020 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1021 		len -= VLAN_ETHER_HDR_SIZE;
1022 	}
1023 
1024 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1025 
1026 #if defined(CONFIG_CMD_CDP)
1027 	if (iscdp) {
1028 		cdp_receive((uchar *)ip, len);
1029 		return;
1030 	}
1031 #endif
1032 
1033 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1034 		if (vlanid == VLAN_NONE)
1035 			vlanid = (mynvlanid & VLAN_IDMASK);
1036 		/* not matched? */
1037 		if (vlanid != (myvlanid & VLAN_IDMASK))
1038 			return;
1039 	}
1040 
1041 	switch (eth_proto) {
1042 
1043 	case PROT_ARP:
1044 		ArpReceive(et, ip, len);
1045 		break;
1046 
1047 #ifdef CONFIG_CMD_RARP
1048 	case PROT_RARP:
1049 		rarp_receive(ip, len);
1050 		break;
1051 #endif
1052 	case PROT_IP:
1053 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1054 		/* Before we start poking the header, make sure it is there */
1055 		if (len < IP_UDP_HDR_SIZE) {
1056 			debug("len bad %d < %lu\n", len,
1057 				(ulong)IP_UDP_HDR_SIZE);
1058 			return;
1059 		}
1060 		/* Check the packet length */
1061 		if (len < ntohs(ip->ip_len)) {
1062 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1063 			return;
1064 		}
1065 		len = ntohs(ip->ip_len);
1066 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1067 			len, ip->ip_hl_v & 0xff);
1068 
1069 		/* Can't deal with anything except IPv4 */
1070 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1071 			return;
1072 		/* Can't deal with IP options (headers != 20 bytes) */
1073 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1074 			return;
1075 		/* Check the Checksum of the header */
1076 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1077 			debug("checksum bad\n");
1078 			return;
1079 		}
1080 		/* If it is not for us, ignore it */
1081 		dst_ip = NetReadIP(&ip->ip_dst);
1082 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1083 #ifdef CONFIG_MCAST_TFTP
1084 			if (Mcast_addr != dst_ip)
1085 #endif
1086 				return;
1087 		}
1088 		/* Read source IP address for later use */
1089 		src_ip = NetReadIP(&ip->ip_src);
1090 		/*
1091 		 * The function returns the unchanged packet if it's not
1092 		 * a fragment, and either the complete packet or NULL if
1093 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1094 		 */
1095 		ip = NetDefragment(ip, &len);
1096 		if (!ip)
1097 			return;
1098 		/*
1099 		 * watch for ICMP host redirects
1100 		 *
1101 		 * There is no real handler code (yet). We just watch
1102 		 * for ICMP host redirect messages. In case anybody
1103 		 * sees these messages: please contact me
1104 		 * (wd@denx.de), or - even better - send me the
1105 		 * necessary fixes :-)
1106 		 *
1107 		 * Note: in all cases where I have seen this so far
1108 		 * it was a problem with the router configuration,
1109 		 * for instance when a router was configured in the
1110 		 * BOOTP reply, but the TFTP server was on the same
1111 		 * subnet. So this is probably a warning that your
1112 		 * configuration might be wrong. But I'm not really
1113 		 * sure if there aren't any other situations.
1114 		 *
1115 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1116 		 * we send a tftp packet to a dead connection, or when
1117 		 * there is no server at the other end.
1118 		 */
1119 		if (ip->ip_p == IPPROTO_ICMP) {
1120 			receive_icmp(ip, len, src_ip, et);
1121 			return;
1122 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1123 			return;
1124 		}
1125 
1126 		debug_cond(DEBUG_DEV_PKT,
1127 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1128 			&dst_ip, &src_ip, len);
1129 
1130 #ifdef CONFIG_UDP_CHECKSUM
1131 		if (ip->udp_xsum != 0) {
1132 			ulong   xsum;
1133 			ushort *sumptr;
1134 			ushort  sumlen;
1135 
1136 			xsum  = ip->ip_p;
1137 			xsum += (ntohs(ip->udp_len));
1138 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1139 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1140 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1141 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1142 
1143 			sumlen = ntohs(ip->udp_len);
1144 			sumptr = (ushort *) &(ip->udp_src);
1145 
1146 			while (sumlen > 1) {
1147 				ushort sumdata;
1148 
1149 				sumdata = *sumptr++;
1150 				xsum += ntohs(sumdata);
1151 				sumlen -= 2;
1152 			}
1153 			if (sumlen > 0) {
1154 				ushort sumdata;
1155 
1156 				sumdata = *(unsigned char *) sumptr;
1157 				sumdata = (sumdata << 8) & 0xff00;
1158 				xsum += sumdata;
1159 			}
1160 			while ((xsum >> 16) != 0) {
1161 				xsum = (xsum & 0x0000ffff) +
1162 				       ((xsum >> 16) & 0x0000ffff);
1163 			}
1164 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1165 				printf(" UDP wrong checksum %08lx %08x\n",
1166 					xsum, ntohs(ip->udp_xsum));
1167 				return;
1168 			}
1169 		}
1170 #endif
1171 
1172 
1173 #ifdef CONFIG_NETCONSOLE
1174 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1175 					src_ip,
1176 					ntohs(ip->udp_dst),
1177 					ntohs(ip->udp_src),
1178 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1179 #endif
1180 		/*
1181 		 *	IP header OK.  Pass the packet to the current handler.
1182 		 */
1183 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1184 				ntohs(ip->udp_dst),
1185 				src_ip,
1186 				ntohs(ip->udp_src),
1187 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1188 		break;
1189 	}
1190 }
1191 
1192 
1193 /**********************************************************************/
1194 
1195 static int net_check_prereq(enum proto_t protocol)
1196 {
1197 	switch (protocol) {
1198 		/* Fall through */
1199 #if defined(CONFIG_CMD_PING)
1200 	case PING:
1201 		if (NetPingIP == 0) {
1202 			puts("*** ERROR: ping address not given\n");
1203 			return 1;
1204 		}
1205 		goto common;
1206 #endif
1207 #if defined(CONFIG_CMD_SNTP)
1208 	case SNTP:
1209 		if (NetNtpServerIP == 0) {
1210 			puts("*** ERROR: NTP server address not given\n");
1211 			return 1;
1212 		}
1213 		goto common;
1214 #endif
1215 #if defined(CONFIG_CMD_DNS)
1216 	case DNS:
1217 		if (NetOurDNSIP == 0) {
1218 			puts("*** ERROR: DNS server address not given\n");
1219 			return 1;
1220 		}
1221 		goto common;
1222 #endif
1223 #if defined(CONFIG_CMD_NFS)
1224 	case NFS:
1225 #endif
1226 	case TFTPGET:
1227 	case TFTPPUT:
1228 		if (NetServerIP == 0) {
1229 			puts("*** ERROR: `serverip' not set\n");
1230 			return 1;
1231 		}
1232 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1233 	defined(CONFIG_CMD_DNS)
1234 common:
1235 #endif
1236 		/* Fall through */
1237 
1238 	case NETCONS:
1239 	case TFTPSRV:
1240 		if (NetOurIP == 0) {
1241 			puts("*** ERROR: `ipaddr' not set\n");
1242 			return 1;
1243 		}
1244 		/* Fall through */
1245 
1246 #ifdef CONFIG_CMD_RARP
1247 	case RARP:
1248 #endif
1249 	case BOOTP:
1250 	case CDP:
1251 	case DHCP:
1252 	case LINKLOCAL:
1253 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1254 			int num = eth_get_dev_index();
1255 
1256 			switch (num) {
1257 			case -1:
1258 				puts("*** ERROR: No ethernet found.\n");
1259 				return 1;
1260 			case 0:
1261 				puts("*** ERROR: `ethaddr' not set\n");
1262 				break;
1263 			default:
1264 				printf("*** ERROR: `eth%daddr' not set\n",
1265 					num);
1266 				break;
1267 			}
1268 
1269 			NetStartAgain();
1270 			return 2;
1271 		}
1272 		/* Fall through */
1273 	default:
1274 		return 0;
1275 	}
1276 	return 0;		/* OK */
1277 }
1278 /**********************************************************************/
1279 
1280 int
1281 NetCksumOk(uchar *ptr, int len)
1282 {
1283 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1284 }
1285 
1286 
1287 unsigned
1288 NetCksum(uchar *ptr, int len)
1289 {
1290 	ulong	xsum;
1291 	ushort *p = (ushort *)ptr;
1292 
1293 	xsum = 0;
1294 	while (len-- > 0)
1295 		xsum += *p++;
1296 	xsum = (xsum & 0xffff) + (xsum >> 16);
1297 	xsum = (xsum & 0xffff) + (xsum >> 16);
1298 	return xsum & 0xffff;
1299 }
1300 
1301 int
1302 NetEthHdrSize(void)
1303 {
1304 	ushort myvlanid;
1305 
1306 	myvlanid = ntohs(NetOurVLAN);
1307 	if (myvlanid == (ushort)-1)
1308 		myvlanid = VLAN_NONE;
1309 
1310 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1311 		VLAN_ETHER_HDR_SIZE;
1312 }
1313 
1314 int
1315 NetSetEther(uchar *xet, uchar * addr, uint prot)
1316 {
1317 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1318 	ushort myvlanid;
1319 
1320 	myvlanid = ntohs(NetOurVLAN);
1321 	if (myvlanid == (ushort)-1)
1322 		myvlanid = VLAN_NONE;
1323 
1324 	memcpy(et->et_dest, addr, 6);
1325 	memcpy(et->et_src, NetOurEther, 6);
1326 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1327 		et->et_protlen = htons(prot);
1328 		return ETHER_HDR_SIZE;
1329 	} else {
1330 		struct vlan_ethernet_hdr *vet =
1331 			(struct vlan_ethernet_hdr *)xet;
1332 
1333 		vet->vet_vlan_type = htons(PROT_VLAN);
1334 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1335 		vet->vet_type = htons(prot);
1336 		return VLAN_ETHER_HDR_SIZE;
1337 	}
1338 }
1339 
1340 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1341 {
1342 	ushort protlen;
1343 
1344 	memcpy(et->et_dest, addr, 6);
1345 	memcpy(et->et_src, NetOurEther, 6);
1346 	protlen = ntohs(et->et_protlen);
1347 	if (protlen == PROT_VLAN) {
1348 		struct vlan_ethernet_hdr *vet =
1349 			(struct vlan_ethernet_hdr *)et;
1350 		vet->vet_type = htons(prot);
1351 		return VLAN_ETHER_HDR_SIZE;
1352 	} else if (protlen > 1514) {
1353 		et->et_protlen = htons(prot);
1354 		return ETHER_HDR_SIZE;
1355 	} else {
1356 		/* 802.2 + SNAP */
1357 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1358 		et802->et_prot = htons(prot);
1359 		return E802_HDR_SIZE;
1360 	}
1361 }
1362 
1363 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1364 {
1365 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1366 
1367 	/*
1368 	 *	Construct an IP header.
1369 	 */
1370 	/* IP_HDR_SIZE / 4 (not including UDP) */
1371 	ip->ip_hl_v  = 0x45;
1372 	ip->ip_tos   = 0;
1373 	ip->ip_len   = htons(IP_HDR_SIZE);
1374 	ip->ip_id    = htons(NetIPID++);
1375 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1376 	ip->ip_ttl   = 255;
1377 	ip->ip_sum   = 0;
1378 	/* already in network byte order */
1379 	NetCopyIP((void *)&ip->ip_src, &source);
1380 	/* already in network byte order */
1381 	NetCopyIP((void *)&ip->ip_dst, &dest);
1382 }
1383 
1384 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1385 			int len)
1386 {
1387 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1388 
1389 	/*
1390 	 *	If the data is an odd number of bytes, zero the
1391 	 *	byte after the last byte so that the checksum
1392 	 *	will work.
1393 	 */
1394 	if (len & 1)
1395 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1396 
1397 	net_set_ip_header(pkt, dest, NetOurIP);
1398 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1399 	ip->ip_p     = IPPROTO_UDP;
1400 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1401 
1402 	ip->udp_src  = htons(sport);
1403 	ip->udp_dst  = htons(dport);
1404 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1405 	ip->udp_xsum = 0;
1406 }
1407 
1408 void copy_filename(char *dst, const char *src, int size)
1409 {
1410 	if (*src && (*src == '"')) {
1411 		++src;
1412 		--size;
1413 	}
1414 
1415 	while ((--size > 0) && *src && (*src != '"'))
1416 		*dst++ = *src++;
1417 	*dst = '\0';
1418 }
1419 
1420 #if	defined(CONFIG_CMD_NFS)		|| \
1421 	defined(CONFIG_CMD_SNTP)	|| \
1422 	defined(CONFIG_CMD_DNS)
1423 /*
1424  * make port a little random (1024-17407)
1425  * This keeps the math somewhat trivial to compute, and seems to work with
1426  * all supported protocols/clients/servers
1427  */
1428 unsigned int random_port(void)
1429 {
1430 	return 1024 + (get_timer(0) % 0x4000);
1431 }
1432 #endif
1433 
1434 void ip_to_string(IPaddr_t x, char *s)
1435 {
1436 	x = ntohl(x);
1437 	sprintf(s, "%d.%d.%d.%d",
1438 		(int) ((x >> 24) & 0xff),
1439 		(int) ((x >> 16) & 0xff),
1440 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1441 	);
1442 }
1443 
1444 void VLAN_to_string(ushort x, char *s)
1445 {
1446 	x = ntohs(x);
1447 
1448 	if (x == (ushort)-1)
1449 		x = VLAN_NONE;
1450 
1451 	if (x == VLAN_NONE)
1452 		strcpy(s, "none");
1453 	else
1454 		sprintf(s, "%d", x & VLAN_IDMASK);
1455 }
1456 
1457 ushort string_to_VLAN(const char *s)
1458 {
1459 	ushort id;
1460 
1461 	if (s == NULL)
1462 		return htons(VLAN_NONE);
1463 
1464 	if (*s < '0' || *s > '9')
1465 		id = VLAN_NONE;
1466 	else
1467 		id = (ushort)simple_strtoul(s, NULL, 10);
1468 
1469 	return htons(id);
1470 }
1471 
1472 ushort getenv_VLAN(char *var)
1473 {
1474 	return string_to_VLAN(getenv(var));
1475 }
1476