xref: /openbmc/u-boot/net/net.c (revision 58d423b8)
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  *	SPDX-License-Identifier:	GPL-2.0
10  */
11 
12 /*
13  * General Desription:
14  *
15  * The user interface supports commands for BOOTP, RARP, and TFTP.
16  * Also, we support ARP internally. Depending on available data,
17  * these interact as follows:
18  *
19  * BOOTP:
20  *
21  *	Prerequisites:	- own ethernet address
22  *	We want:	- own IP address
23  *			- TFTP server IP address
24  *			- name of bootfile
25  *	Next step:	ARP
26  *
27  * LINK_LOCAL:
28  *
29  *	Prerequisites:	- own ethernet address
30  *	We want:	- own IP address
31  *	Next step:	ARP
32  *
33  * RARP:
34  *
35  *	Prerequisites:	- own ethernet address
36  *	We want:	- own IP address
37  *			- TFTP server IP address
38  *	Next step:	ARP
39  *
40  * ARP:
41  *
42  *	Prerequisites:	- own ethernet address
43  *			- own IP address
44  *			- TFTP server IP address
45  *	We want:	- TFTP server ethernet address
46  *	Next step:	TFTP
47  *
48  * DHCP:
49  *
50  *     Prerequisites:	- own ethernet address
51  *     We want:		- IP, Netmask, ServerIP, Gateway IP
52  *			- bootfilename, lease time
53  *     Next step:	- TFTP
54  *
55  * TFTP:
56  *
57  *	Prerequisites:	- own ethernet address
58  *			- own IP address
59  *			- TFTP server IP address
60  *			- TFTP server ethernet address
61  *			- name of bootfile (if unknown, we use a default name
62  *			  derived from our own IP address)
63  *	We want:	- load the boot file
64  *	Next step:	none
65  *
66  * NFS:
67  *
68  *	Prerequisites:	- own ethernet address
69  *			- own IP address
70  *			- name of bootfile (if unknown, we use a default name
71  *			  derived from our own IP address)
72  *	We want:	- load the boot file
73  *	Next step:	none
74  *
75  * SNTP:
76  *
77  *	Prerequisites:	- own ethernet address
78  *			- own IP address
79  *	We want:	- network time
80  *	Next step:	none
81  */
82 
83 
84 #include <common.h>
85 #include <command.h>
86 #include <environment.h>
87 #include <errno.h>
88 #include <net.h>
89 #if defined(CONFIG_STATUS_LED)
90 #include <miiphy.h>
91 #include <status_led.h>
92 #endif
93 #include <watchdog.h>
94 #include <linux/compiler.h>
95 #include "arp.h"
96 #include "bootp.h"
97 #include "cdp.h"
98 #if defined(CONFIG_CMD_DNS)
99 #include "dns.h"
100 #endif
101 #include "link_local.h"
102 #include "nfs.h"
103 #include "ping.h"
104 #include "rarp.h"
105 #if defined(CONFIG_CMD_SNTP)
106 #include "sntp.h"
107 #endif
108 #include "tftp.h"
109 
110 DECLARE_GLOBAL_DATA_PTR;
111 
112 /** BOOTP EXTENTIONS **/
113 
114 /* Our subnet mask (0=unknown) */
115 IPaddr_t	NetOurSubnetMask;
116 /* Our gateways IP address */
117 IPaddr_t	NetOurGatewayIP;
118 /* Our DNS IP address */
119 IPaddr_t	NetOurDNSIP;
120 #if defined(CONFIG_BOOTP_DNS2)
121 /* Our 2nd DNS IP address */
122 IPaddr_t	NetOurDNS2IP;
123 #endif
124 /* Our NIS domain */
125 char		NetOurNISDomain[32] = {0,};
126 /* Our hostname */
127 char		NetOurHostName[32] = {0,};
128 /* Our bootpath */
129 char		NetOurRootPath[64] = {0,};
130 /* Our bootfile size in blocks */
131 ushort		NetBootFileSize;
132 
133 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
134 IPaddr_t Mcast_addr;
135 #endif
136 
137 /** END OF BOOTP EXTENTIONS **/
138 
139 /* The actual transferred size of the bootfile (in bytes) */
140 ulong		NetBootFileXferSize;
141 /* Our ethernet address */
142 uchar		NetOurEther[6];
143 /* Boot server enet address */
144 uchar		NetServerEther[6];
145 /* Our IP addr (0 = unknown) */
146 IPaddr_t	NetOurIP;
147 /* Server IP addr (0 = unknown) */
148 IPaddr_t	NetServerIP;
149 /* Current receive packet */
150 uchar *NetRxPacket;
151 /* Current rx packet length */
152 int		NetRxPacketLen;
153 /* IP packet ID */
154 unsigned	NetIPID;
155 /* Ethernet bcast address */
156 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
157 uchar		NetEtherNullAddr[6];
158 #ifdef CONFIG_API
159 void		(*push_packet)(void *, int len) = 0;
160 #endif
161 /* Network loop state */
162 enum net_loop_state net_state;
163 /* Tried all network devices */
164 int		NetRestartWrap;
165 /* Network loop restarted */
166 static int	NetRestarted;
167 /* At least one device configured */
168 static int	NetDevExists;
169 
170 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
171 /* default is without VLAN */
172 ushort		NetOurVLAN = 0xFFFF;
173 /* ditto */
174 ushort		NetOurNativeVLAN = 0xFFFF;
175 
176 /* Boot File name */
177 char		BootFile[128];
178 
179 #if defined(CONFIG_CMD_SNTP)
180 /* NTP server IP address */
181 IPaddr_t	NetNtpServerIP;
182 /* offset time from UTC */
183 int		NetTimeOffset;
184 #endif
185 
186 static uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
187 #ifdef CONFIG_DM_ETH
188 /* Receive packets */
189 uchar *net_rx_packets[PKTBUFSRX];
190 #else
191 /* Receive packet */
192 uchar *NetRxPackets[PKTBUFSRX];
193 #endif
194 /* Current UDP RX packet handler */
195 static rxhand_f *udp_packet_handler;
196 /* Current ARP RX packet handler */
197 static rxhand_f *arp_packet_handler;
198 #ifdef CONFIG_CMD_TFTPPUT
199 /* Current ICMP rx handler */
200 static rxhand_icmp_f *packet_icmp_handler;
201 #endif
202 /* Current timeout handler */
203 static thand_f *timeHandler;
204 /* Time base value */
205 static ulong	timeStart;
206 /* Current timeout value */
207 static ulong	timeDelta;
208 /* THE transmit packet */
209 uchar *NetTxPacket;
210 
211 static int net_check_prereq(enum proto_t protocol);
212 
213 static int NetTryCount;
214 
215 int __maybe_unused net_busy_flag;
216 
217 /**********************************************************************/
218 
219 static int on_bootfile(const char *name, const char *value, enum env_op op,
220 	int flags)
221 {
222 	switch (op) {
223 	case env_op_create:
224 	case env_op_overwrite:
225 		copy_filename(BootFile, value, sizeof(BootFile));
226 		break;
227 	default:
228 		break;
229 	}
230 
231 	return 0;
232 }
233 U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
234 
235 /*
236  * Check if autoload is enabled. If so, use either NFS or TFTP to download
237  * the boot file.
238  */
239 void net_auto_load(void)
240 {
241 #if defined(CONFIG_CMD_NFS)
242 	const char *s = getenv("autoload");
243 
244 	if (s != NULL && strcmp(s, "NFS") == 0) {
245 		/*
246 		 * Use NFS to load the bootfile.
247 		 */
248 		NfsStart();
249 		return;
250 	}
251 #endif
252 	if (getenv_yesno("autoload") == 0) {
253 		/*
254 		 * Just use BOOTP/RARP to configure system;
255 		 * Do not use TFTP to load the bootfile.
256 		 */
257 		net_set_state(NETLOOP_SUCCESS);
258 		return;
259 	}
260 	TftpStart(TFTPGET);
261 }
262 
263 static void NetInitLoop(void)
264 {
265 	static int env_changed_id;
266 	int env_id = get_env_id();
267 
268 	/* update only when the environment has changed */
269 	if (env_changed_id != env_id) {
270 		NetOurIP = getenv_IPaddr("ipaddr");
271 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
272 		NetOurSubnetMask = getenv_IPaddr("netmask");
273 		NetServerIP = getenv_IPaddr("serverip");
274 		NetOurNativeVLAN = getenv_VLAN("nvlan");
275 		NetOurVLAN = getenv_VLAN("vlan");
276 #if defined(CONFIG_CMD_DNS)
277 		NetOurDNSIP = getenv_IPaddr("dnsip");
278 #endif
279 		env_changed_id = env_id;
280 	}
281 	if (eth_get_dev())
282 		memcpy(NetOurEther, eth_get_ethaddr(), 6);
283 
284 	return;
285 }
286 
287 static void net_clear_handlers(void)
288 {
289 	net_set_udp_handler(NULL);
290 	net_set_arp_handler(NULL);
291 	NetSetTimeout(0, NULL);
292 }
293 
294 static void net_cleanup_loop(void)
295 {
296 	net_clear_handlers();
297 }
298 
299 void net_init(void)
300 {
301 	static int first_call = 1;
302 
303 	if (first_call) {
304 		/*
305 		 *	Setup packet buffers, aligned correctly.
306 		 */
307 		int i;
308 
309 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
310 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
311 #ifdef CONFIG_DM_ETH
312 		for (i = 0; i < PKTBUFSRX; i++) {
313 			net_rx_packets[i] = NetTxPacket + (i + 1) *
314 				PKTSIZE_ALIGN;
315 		}
316 #else
317 		for (i = 0; i < PKTBUFSRX; i++)
318 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
319 #endif
320 		ArpInit();
321 		net_clear_handlers();
322 
323 		/* Only need to setup buffer pointers once. */
324 		first_call = 0;
325 	}
326 
327 	NetInitLoop();
328 }
329 
330 /**********************************************************************/
331 /*
332  *	Main network processing loop.
333  */
334 
335 int NetLoop(enum proto_t protocol)
336 {
337 	int ret = -EINVAL;
338 
339 	NetRestarted = 0;
340 	NetDevExists = 0;
341 	NetTryCount = 1;
342 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
343 
344 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
345 	net_init();
346 	if (eth_is_on_demand_init() || protocol != NETCONS) {
347 		eth_halt();
348 		eth_set_current();
349 		ret = eth_init();
350 		if (ret < 0) {
351 			eth_halt();
352 			return ret;
353 		}
354 	} else
355 		eth_init_state_only();
356 
357 restart:
358 #ifdef CONFIG_USB_KEYBOARD
359 	net_busy_flag = 0;
360 #endif
361 	net_set_state(NETLOOP_CONTINUE);
362 
363 	/*
364 	 *	Start the ball rolling with the given start function.  From
365 	 *	here on, this code is a state machine driven by received
366 	 *	packets and timer events.
367 	 */
368 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
369 	NetInitLoop();
370 
371 	switch (net_check_prereq(protocol)) {
372 	case 1:
373 		/* network not configured */
374 		eth_halt();
375 		return -ENODEV;
376 
377 	case 2:
378 		/* network device not configured */
379 		break;
380 
381 	case 0:
382 		NetDevExists = 1;
383 		NetBootFileXferSize = 0;
384 		switch (protocol) {
385 		case TFTPGET:
386 #ifdef CONFIG_CMD_TFTPPUT
387 		case TFTPPUT:
388 #endif
389 			/* always use ARP to get server ethernet address */
390 			TftpStart(protocol);
391 			break;
392 #ifdef CONFIG_CMD_TFTPSRV
393 		case TFTPSRV:
394 			TftpStartServer();
395 			break;
396 #endif
397 #if defined(CONFIG_CMD_DHCP)
398 		case DHCP:
399 			BootpReset();
400 			NetOurIP = 0;
401 			DhcpRequest();		/* Basically same as BOOTP */
402 			break;
403 #endif
404 
405 		case BOOTP:
406 			BootpReset();
407 			NetOurIP = 0;
408 			BootpRequest();
409 			break;
410 
411 #if defined(CONFIG_CMD_RARP)
412 		case RARP:
413 			RarpTry = 0;
414 			NetOurIP = 0;
415 			RarpRequest();
416 			break;
417 #endif
418 #if defined(CONFIG_CMD_PING)
419 		case PING:
420 			ping_start();
421 			break;
422 #endif
423 #if defined(CONFIG_CMD_NFS)
424 		case NFS:
425 			NfsStart();
426 			break;
427 #endif
428 #if defined(CONFIG_CMD_CDP)
429 		case CDP:
430 			CDPStart();
431 			break;
432 #endif
433 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
434 		case NETCONS:
435 			NcStart();
436 			break;
437 #endif
438 #if defined(CONFIG_CMD_SNTP)
439 		case SNTP:
440 			SntpStart();
441 			break;
442 #endif
443 #if defined(CONFIG_CMD_DNS)
444 		case DNS:
445 			DnsStart();
446 			break;
447 #endif
448 #if defined(CONFIG_CMD_LINK_LOCAL)
449 		case LINKLOCAL:
450 			link_local_start();
451 			break;
452 #endif
453 		default:
454 			break;
455 		}
456 
457 		break;
458 	}
459 
460 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
461 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
462 	defined(CONFIG_STATUS_LED)			&& \
463 	defined(STATUS_LED_RED)
464 	/*
465 	 * Echo the inverted link state to the fault LED.
466 	 */
467 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
468 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
469 	else
470 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
471 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
472 #endif /* CONFIG_MII, ... */
473 #ifdef CONFIG_USB_KEYBOARD
474 	net_busy_flag = 1;
475 #endif
476 
477 	/*
478 	 *	Main packet reception loop.  Loop receiving packets until
479 	 *	someone sets `net_state' to a state that terminates.
480 	 */
481 	for (;;) {
482 		WATCHDOG_RESET();
483 #ifdef CONFIG_SHOW_ACTIVITY
484 		show_activity(1);
485 #endif
486 		/*
487 		 *	Check the ethernet for a new packet.  The ethernet
488 		 *	receive routine will process it.
489 		 *	Most drivers return the most recent packet size, but not
490 		 *	errors that may have happened.
491 		 */
492 		eth_rx();
493 
494 		/*
495 		 *	Abort if ctrl-c was pressed.
496 		 */
497 		if (ctrlc()) {
498 			/* cancel any ARP that may not have completed */
499 			NetArpWaitPacketIP = 0;
500 
501 			net_cleanup_loop();
502 			eth_halt();
503 			/* Invalidate the last protocol */
504 			eth_set_last_protocol(BOOTP);
505 
506 			puts("\nAbort\n");
507 			/* include a debug print as well incase the debug
508 			   messages are directed to stderr */
509 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
510 			goto done;
511 		}
512 
513 		ArpTimeoutCheck();
514 
515 		/*
516 		 *	Check for a timeout, and run the timeout handler
517 		 *	if we have one.
518 		 */
519 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
520 			thand_f *x;
521 
522 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
523 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
524 	defined(CONFIG_STATUS_LED)			&& \
525 	defined(STATUS_LED_RED)
526 			/*
527 			 * Echo the inverted link state to the fault LED.
528 			 */
529 			if (miiphy_link(eth_get_dev()->name,
530 				       CONFIG_SYS_FAULT_MII_ADDR)) {
531 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
532 			} else {
533 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
534 			}
535 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
536 #endif /* CONFIG_MII, ... */
537 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
538 			x = timeHandler;
539 			timeHandler = (thand_f *)0;
540 			(*x)();
541 		}
542 
543 		if (net_state == NETLOOP_FAIL)
544 			ret = NetStartAgain();
545 
546 		switch (net_state) {
547 
548 		case NETLOOP_RESTART:
549 			NetRestarted = 1;
550 			goto restart;
551 
552 		case NETLOOP_SUCCESS:
553 			net_cleanup_loop();
554 			if (NetBootFileXferSize > 0) {
555 				printf("Bytes transferred = %ld (%lx hex)\n",
556 					NetBootFileXferSize,
557 					NetBootFileXferSize);
558 				setenv_hex("filesize", NetBootFileXferSize);
559 				setenv_hex("fileaddr", load_addr);
560 			}
561 			if (protocol != NETCONS)
562 				eth_halt();
563 			else
564 				eth_halt_state_only();
565 
566 			eth_set_last_protocol(protocol);
567 
568 			ret = NetBootFileXferSize;
569 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
570 			goto done;
571 
572 		case NETLOOP_FAIL:
573 			net_cleanup_loop();
574 			/* Invalidate the last protocol */
575 			eth_set_last_protocol(BOOTP);
576 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
577 			goto done;
578 
579 		case NETLOOP_CONTINUE:
580 			continue;
581 		}
582 	}
583 
584 done:
585 #ifdef CONFIG_USB_KEYBOARD
586 	net_busy_flag = 0;
587 #endif
588 #ifdef CONFIG_CMD_TFTPPUT
589 	/* Clear out the handlers */
590 	net_set_udp_handler(NULL);
591 	net_set_icmp_handler(NULL);
592 #endif
593 	return ret;
594 }
595 
596 /**********************************************************************/
597 
598 static void
599 startAgainTimeout(void)
600 {
601 	net_set_state(NETLOOP_RESTART);
602 }
603 
604 int NetStartAgain(void)
605 {
606 	char *nretry;
607 	int retry_forever = 0;
608 	unsigned long retrycnt = 0;
609 	int ret;
610 
611 	nretry = getenv("netretry");
612 	if (nretry) {
613 		if (!strcmp(nretry, "yes"))
614 			retry_forever = 1;
615 		else if (!strcmp(nretry, "no"))
616 			retrycnt = 0;
617 		else if (!strcmp(nretry, "once"))
618 			retrycnt = 1;
619 		else
620 			retrycnt = simple_strtoul(nretry, NULL, 0);
621 	} else {
622 		retrycnt = 0;
623 		retry_forever = 0;
624 	}
625 
626 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
627 		eth_halt();
628 		net_set_state(NETLOOP_FAIL);
629 		/*
630 		 * We don't provide a way for the protocol to return an error,
631 		 * but this is almost always the reason.
632 		 */
633 		return -ETIMEDOUT;
634 	}
635 
636 	NetTryCount++;
637 
638 	eth_halt();
639 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
640 	eth_try_another(!NetRestarted);
641 #endif
642 	ret = eth_init();
643 	if (NetRestartWrap) {
644 		NetRestartWrap = 0;
645 		if (NetDevExists) {
646 			NetSetTimeout(10000UL, startAgainTimeout);
647 			net_set_udp_handler(NULL);
648 		} else {
649 			net_set_state(NETLOOP_FAIL);
650 		}
651 	} else {
652 		net_set_state(NETLOOP_RESTART);
653 	}
654 	return ret;
655 }
656 
657 /**********************************************************************/
658 /*
659  *	Miscelaneous bits.
660  */
661 
662 static void dummy_handler(uchar *pkt, unsigned dport,
663 			IPaddr_t sip, unsigned sport,
664 			unsigned len)
665 {
666 }
667 
668 rxhand_f *net_get_udp_handler(void)
669 {
670 	return udp_packet_handler;
671 }
672 
673 void net_set_udp_handler(rxhand_f *f)
674 {
675 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
676 	if (f == NULL)
677 		udp_packet_handler = dummy_handler;
678 	else
679 		udp_packet_handler = f;
680 }
681 
682 rxhand_f *net_get_arp_handler(void)
683 {
684 	return arp_packet_handler;
685 }
686 
687 void net_set_arp_handler(rxhand_f *f)
688 {
689 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
690 	if (f == NULL)
691 		arp_packet_handler = dummy_handler;
692 	else
693 		arp_packet_handler = f;
694 }
695 
696 #ifdef CONFIG_CMD_TFTPPUT
697 void net_set_icmp_handler(rxhand_icmp_f *f)
698 {
699 	packet_icmp_handler = f;
700 }
701 #endif
702 
703 void
704 NetSetTimeout(ulong iv, thand_f *f)
705 {
706 	if (iv == 0) {
707 		debug_cond(DEBUG_INT_STATE,
708 			"--- NetLoop timeout handler cancelled\n");
709 		timeHandler = (thand_f *)0;
710 	} else {
711 		debug_cond(DEBUG_INT_STATE,
712 			"--- NetLoop timeout handler set (%p)\n", f);
713 		timeHandler = f;
714 		timeStart = get_timer(0);
715 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
716 	}
717 }
718 
719 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
720 		int payload_len)
721 {
722 	uchar *pkt;
723 	int eth_hdr_size;
724 	int pkt_hdr_size;
725 
726 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
727 	assert(NetTxPacket != NULL);
728 	if (NetTxPacket == NULL)
729 		return -1;
730 
731 	/* convert to new style broadcast */
732 	if (dest == 0)
733 		dest = 0xFFFFFFFF;
734 
735 	/* if broadcast, make the ether address a broadcast and don't do ARP */
736 	if (dest == 0xFFFFFFFF)
737 		ether = NetBcastAddr;
738 
739 	pkt = (uchar *)NetTxPacket;
740 
741 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
742 	pkt += eth_hdr_size;
743 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
744 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
745 
746 	/* if MAC address was not discovered yet, do an ARP request */
747 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
748 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
749 
750 		/* save the ip and eth addr for the packet to send after arp */
751 		NetArpWaitPacketIP = dest;
752 		NetArpWaitPacketMAC = ether;
753 
754 		/* size of the waiting packet */
755 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
756 
757 		/* and do the ARP request */
758 		NetArpWaitTry = 1;
759 		NetArpWaitTimerStart = get_timer(0);
760 		ArpRequest();
761 		return 1;	/* waiting */
762 	} else {
763 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
764 			&dest, ether);
765 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
766 		return 0;	/* transmitted */
767 	}
768 }
769 
770 #ifdef CONFIG_IP_DEFRAG
771 /*
772  * This function collects fragments in a single packet, according
773  * to the algorithm in RFC815. It returns NULL or the pointer to
774  * a complete packet, in static storage
775  */
776 #ifndef CONFIG_NET_MAXDEFRAG
777 #define CONFIG_NET_MAXDEFRAG 16384
778 #endif
779 /*
780  * MAXDEFRAG, above, is chosen in the config file and  is real data
781  * so we need to add the NFS overhead, which is more than TFTP.
782  * To use sizeof in the internal unnamed structures, we need a real
783  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
784  * The compiler doesn't complain nor allocates the actual structure
785  */
786 static struct rpc_t rpc_specimen;
787 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
788 
789 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
790 
791 /*
792  * this is the packet being assembled, either data or frag control.
793  * Fragments go by 8 bytes, so this union must be 8 bytes long
794  */
795 struct hole {
796 	/* first_byte is address of this structure */
797 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
798 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
799 	u16 prev_hole;	/* index of prev, 0 == none */
800 	u16 unused;
801 };
802 
803 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
804 {
805 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
806 	static u16 first_hole, total_len;
807 	struct hole *payload, *thisfrag, *h, *newh;
808 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
809 	uchar *indata = (uchar *)ip;
810 	int offset8, start, len, done = 0;
811 	u16 ip_off = ntohs(ip->ip_off);
812 
813 	/* payload starts after IP header, this fragment is in there */
814 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
815 	offset8 =  (ip_off & IP_OFFS);
816 	thisfrag = payload + offset8;
817 	start = offset8 * 8;
818 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
819 
820 	if (start + len > IP_MAXUDP) /* fragment extends too far */
821 		return NULL;
822 
823 	if (!total_len || localip->ip_id != ip->ip_id) {
824 		/* new (or different) packet, reset structs */
825 		total_len = 0xffff;
826 		payload[0].last_byte = ~0;
827 		payload[0].next_hole = 0;
828 		payload[0].prev_hole = 0;
829 		first_hole = 0;
830 		/* any IP header will work, copy the first we received */
831 		memcpy(localip, ip, IP_HDR_SIZE);
832 	}
833 
834 	/*
835 	 * What follows is the reassembly algorithm. We use the payload
836 	 * array as a linked list of hole descriptors, as each hole starts
837 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
838 	 * so it is represented as byte count, not as 8-byte blocks.
839 	 */
840 
841 	h = payload + first_hole;
842 	while (h->last_byte < start) {
843 		if (!h->next_hole) {
844 			/* no hole that far away */
845 			return NULL;
846 		}
847 		h = payload + h->next_hole;
848 	}
849 
850 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
851 	if (offset8 + ((len + 7) / 8) <= h - payload) {
852 		/* no overlap with holes (dup fragment?) */
853 		return NULL;
854 	}
855 
856 	if (!(ip_off & IP_FLAGS_MFRAG)) {
857 		/* no more fragmentss: truncate this (last) hole */
858 		total_len = start + len;
859 		h->last_byte = start + len;
860 	}
861 
862 	/*
863 	 * There is some overlap: fix the hole list. This code doesn't
864 	 * deal with a fragment that overlaps with two different holes
865 	 * (thus being a superset of a previously-received fragment).
866 	 */
867 
868 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
869 		/* complete overlap with hole: remove hole */
870 		if (!h->prev_hole && !h->next_hole) {
871 			/* last remaining hole */
872 			done = 1;
873 		} else if (!h->prev_hole) {
874 			/* first hole */
875 			first_hole = h->next_hole;
876 			payload[h->next_hole].prev_hole = 0;
877 		} else if (!h->next_hole) {
878 			/* last hole */
879 			payload[h->prev_hole].next_hole = 0;
880 		} else {
881 			/* in the middle of the list */
882 			payload[h->next_hole].prev_hole = h->prev_hole;
883 			payload[h->prev_hole].next_hole = h->next_hole;
884 		}
885 
886 	} else if (h->last_byte <= start + len) {
887 		/* overlaps with final part of the hole: shorten this hole */
888 		h->last_byte = start;
889 
890 	} else if (h >= thisfrag) {
891 		/* overlaps with initial part of the hole: move this hole */
892 		newh = thisfrag + (len / 8);
893 		*newh = *h;
894 		h = newh;
895 		if (h->next_hole)
896 			payload[h->next_hole].prev_hole = (h - payload);
897 		if (h->prev_hole)
898 			payload[h->prev_hole].next_hole = (h - payload);
899 		else
900 			first_hole = (h - payload);
901 
902 	} else {
903 		/* fragment sits in the middle: split the hole */
904 		newh = thisfrag + (len / 8);
905 		*newh = *h;
906 		h->last_byte = start;
907 		h->next_hole = (newh - payload);
908 		newh->prev_hole = (h - payload);
909 		if (newh->next_hole)
910 			payload[newh->next_hole].prev_hole = (newh - payload);
911 	}
912 
913 	/* finally copy this fragment and possibly return whole packet */
914 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
915 	if (!done)
916 		return NULL;
917 
918 	localip->ip_len = htons(total_len);
919 	*lenp = total_len + IP_HDR_SIZE;
920 	return localip;
921 }
922 
923 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
924 {
925 	u16 ip_off = ntohs(ip->ip_off);
926 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
927 		return ip; /* not a fragment */
928 	return __NetDefragment(ip, lenp);
929 }
930 
931 #else /* !CONFIG_IP_DEFRAG */
932 
933 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
934 {
935 	u16 ip_off = ntohs(ip->ip_off);
936 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
937 		return ip; /* not a fragment */
938 	return NULL;
939 }
940 #endif
941 
942 /**
943  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
944  * drop others.
945  *
946  * @parma ip	IP packet containing the ICMP
947  */
948 static void receive_icmp(struct ip_udp_hdr *ip, int len,
949 			IPaddr_t src_ip, struct ethernet_hdr *et)
950 {
951 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
952 
953 	switch (icmph->type) {
954 	case ICMP_REDIRECT:
955 		if (icmph->code != ICMP_REDIR_HOST)
956 			return;
957 		printf(" ICMP Host Redirect to %pI4 ",
958 			&icmph->un.gateway);
959 		break;
960 	default:
961 #if defined(CONFIG_CMD_PING)
962 		ping_receive(et, ip, len);
963 #endif
964 #ifdef CONFIG_CMD_TFTPPUT
965 		if (packet_icmp_handler)
966 			packet_icmp_handler(icmph->type, icmph->code,
967 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
968 				icmph->un.data, ntohs(ip->udp_len));
969 #endif
970 		break;
971 	}
972 }
973 
974 void net_process_received_packet(uchar *in_packet, int len)
975 {
976 	struct ethernet_hdr *et;
977 	struct ip_udp_hdr *ip;
978 	IPaddr_t dst_ip;
979 	IPaddr_t src_ip;
980 	int eth_proto;
981 #if defined(CONFIG_CMD_CDP)
982 	int iscdp;
983 #endif
984 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
985 
986 	debug_cond(DEBUG_NET_PKT, "packet received\n");
987 
988 	NetRxPacket = in_packet;
989 	NetRxPacketLen = len;
990 	et = (struct ethernet_hdr *)in_packet;
991 
992 	/* too small packet? */
993 	if (len < ETHER_HDR_SIZE)
994 		return;
995 
996 #ifdef CONFIG_API
997 	if (push_packet) {
998 		(*push_packet)(in_packet, len);
999 		return;
1000 	}
1001 #endif
1002 
1003 #if defined(CONFIG_CMD_CDP)
1004 	/* keep track if packet is CDP */
1005 	iscdp = is_cdp_packet(et->et_dest);
1006 #endif
1007 
1008 	myvlanid = ntohs(NetOurVLAN);
1009 	if (myvlanid == (ushort)-1)
1010 		myvlanid = VLAN_NONE;
1011 	mynvlanid = ntohs(NetOurNativeVLAN);
1012 	if (mynvlanid == (ushort)-1)
1013 		mynvlanid = VLAN_NONE;
1014 
1015 	eth_proto = ntohs(et->et_protlen);
1016 
1017 	if (eth_proto < 1514) {
1018 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1019 		/*
1020 		 *	Got a 802.2 packet.  Check the other protocol field.
1021 		 *	XXX VLAN over 802.2+SNAP not implemented!
1022 		 */
1023 		eth_proto = ntohs(et802->et_prot);
1024 
1025 		ip = (struct ip_udp_hdr *)(in_packet + E802_HDR_SIZE);
1026 		len -= E802_HDR_SIZE;
1027 
1028 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
1029 		ip = (struct ip_udp_hdr *)(in_packet + ETHER_HDR_SIZE);
1030 		len -= ETHER_HDR_SIZE;
1031 
1032 	} else {			/* VLAN packet */
1033 		struct vlan_ethernet_hdr *vet =
1034 			(struct vlan_ethernet_hdr *)et;
1035 
1036 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1037 
1038 		/* too small packet? */
1039 		if (len < VLAN_ETHER_HDR_SIZE)
1040 			return;
1041 
1042 		/* if no VLAN active */
1043 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1044 #if defined(CONFIG_CMD_CDP)
1045 				&& iscdp == 0
1046 #endif
1047 				)
1048 			return;
1049 
1050 		cti = ntohs(vet->vet_tag);
1051 		vlanid = cti & VLAN_IDMASK;
1052 		eth_proto = ntohs(vet->vet_type);
1053 
1054 		ip = (struct ip_udp_hdr *)(in_packet + VLAN_ETHER_HDR_SIZE);
1055 		len -= VLAN_ETHER_HDR_SIZE;
1056 	}
1057 
1058 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1059 
1060 #if defined(CONFIG_CMD_CDP)
1061 	if (iscdp) {
1062 		cdp_receive((uchar *)ip, len);
1063 		return;
1064 	}
1065 #endif
1066 
1067 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1068 		if (vlanid == VLAN_NONE)
1069 			vlanid = (mynvlanid & VLAN_IDMASK);
1070 		/* not matched? */
1071 		if (vlanid != (myvlanid & VLAN_IDMASK))
1072 			return;
1073 	}
1074 
1075 	switch (eth_proto) {
1076 
1077 	case PROT_ARP:
1078 		ArpReceive(et, ip, len);
1079 		break;
1080 
1081 #ifdef CONFIG_CMD_RARP
1082 	case PROT_RARP:
1083 		rarp_receive(ip, len);
1084 		break;
1085 #endif
1086 	case PROT_IP:
1087 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1088 		/* Before we start poking the header, make sure it is there */
1089 		if (len < IP_UDP_HDR_SIZE) {
1090 			debug("len bad %d < %lu\n", len,
1091 				(ulong)IP_UDP_HDR_SIZE);
1092 			return;
1093 		}
1094 		/* Check the packet length */
1095 		if (len < ntohs(ip->ip_len)) {
1096 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1097 			return;
1098 		}
1099 		len = ntohs(ip->ip_len);
1100 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1101 			len, ip->ip_hl_v & 0xff);
1102 
1103 		/* Can't deal with anything except IPv4 */
1104 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1105 			return;
1106 		/* Can't deal with IP options (headers != 20 bytes) */
1107 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1108 			return;
1109 		/* Check the Checksum of the header */
1110 		if (!ip_checksum_ok((uchar *)ip, IP_HDR_SIZE)) {
1111 			debug("checksum bad\n");
1112 			return;
1113 		}
1114 		/* If it is not for us, ignore it */
1115 		dst_ip = NetReadIP(&ip->ip_dst);
1116 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1117 #ifdef CONFIG_MCAST_TFTP
1118 			if (Mcast_addr != dst_ip)
1119 #endif
1120 				return;
1121 		}
1122 		/* Read source IP address for later use */
1123 		src_ip = NetReadIP(&ip->ip_src);
1124 		/*
1125 		 * The function returns the unchanged packet if it's not
1126 		 * a fragment, and either the complete packet or NULL if
1127 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1128 		 */
1129 		ip = NetDefragment(ip, &len);
1130 		if (!ip)
1131 			return;
1132 		/*
1133 		 * watch for ICMP host redirects
1134 		 *
1135 		 * There is no real handler code (yet). We just watch
1136 		 * for ICMP host redirect messages. In case anybody
1137 		 * sees these messages: please contact me
1138 		 * (wd@denx.de), or - even better - send me the
1139 		 * necessary fixes :-)
1140 		 *
1141 		 * Note: in all cases where I have seen this so far
1142 		 * it was a problem with the router configuration,
1143 		 * for instance when a router was configured in the
1144 		 * BOOTP reply, but the TFTP server was on the same
1145 		 * subnet. So this is probably a warning that your
1146 		 * configuration might be wrong. But I'm not really
1147 		 * sure if there aren't any other situations.
1148 		 *
1149 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1150 		 * we send a tftp packet to a dead connection, or when
1151 		 * there is no server at the other end.
1152 		 */
1153 		if (ip->ip_p == IPPROTO_ICMP) {
1154 			receive_icmp(ip, len, src_ip, et);
1155 			return;
1156 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1157 			return;
1158 		}
1159 
1160 		debug_cond(DEBUG_DEV_PKT,
1161 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1162 			&dst_ip, &src_ip, len);
1163 
1164 #ifdef CONFIG_UDP_CHECKSUM
1165 		if (ip->udp_xsum != 0) {
1166 			ulong   xsum;
1167 			ushort *sumptr;
1168 			ushort  sumlen;
1169 
1170 			xsum  = ip->ip_p;
1171 			xsum += (ntohs(ip->udp_len));
1172 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1173 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1174 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1175 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1176 
1177 			sumlen = ntohs(ip->udp_len);
1178 			sumptr = (ushort *) &(ip->udp_src);
1179 
1180 			while (sumlen > 1) {
1181 				ushort sumdata;
1182 
1183 				sumdata = *sumptr++;
1184 				xsum += ntohs(sumdata);
1185 				sumlen -= 2;
1186 			}
1187 			if (sumlen > 0) {
1188 				ushort sumdata;
1189 
1190 				sumdata = *(unsigned char *) sumptr;
1191 				sumdata = (sumdata << 8) & 0xff00;
1192 				xsum += sumdata;
1193 			}
1194 			while ((xsum >> 16) != 0) {
1195 				xsum = (xsum & 0x0000ffff) +
1196 				       ((xsum >> 16) & 0x0000ffff);
1197 			}
1198 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1199 				printf(" UDP wrong checksum %08lx %08x\n",
1200 					xsum, ntohs(ip->udp_xsum));
1201 				return;
1202 			}
1203 		}
1204 #endif
1205 
1206 
1207 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
1208 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1209 					src_ip,
1210 					ntohs(ip->udp_dst),
1211 					ntohs(ip->udp_src),
1212 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1213 #endif
1214 		/*
1215 		 *	IP header OK.  Pass the packet to the current handler.
1216 		 */
1217 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1218 				ntohs(ip->udp_dst),
1219 				src_ip,
1220 				ntohs(ip->udp_src),
1221 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1222 		break;
1223 	}
1224 }
1225 
1226 
1227 /**********************************************************************/
1228 
1229 static int net_check_prereq(enum proto_t protocol)
1230 {
1231 	switch (protocol) {
1232 		/* Fall through */
1233 #if defined(CONFIG_CMD_PING)
1234 	case PING:
1235 		if (NetPingIP == 0) {
1236 			puts("*** ERROR: ping address not given\n");
1237 			return 1;
1238 		}
1239 		goto common;
1240 #endif
1241 #if defined(CONFIG_CMD_SNTP)
1242 	case SNTP:
1243 		if (NetNtpServerIP == 0) {
1244 			puts("*** ERROR: NTP server address not given\n");
1245 			return 1;
1246 		}
1247 		goto common;
1248 #endif
1249 #if defined(CONFIG_CMD_DNS)
1250 	case DNS:
1251 		if (NetOurDNSIP == 0) {
1252 			puts("*** ERROR: DNS server address not given\n");
1253 			return 1;
1254 		}
1255 		goto common;
1256 #endif
1257 #if defined(CONFIG_CMD_NFS)
1258 	case NFS:
1259 #endif
1260 	case TFTPGET:
1261 	case TFTPPUT:
1262 		if (NetServerIP == 0) {
1263 			puts("*** ERROR: `serverip' not set\n");
1264 			return 1;
1265 		}
1266 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1267 	defined(CONFIG_CMD_DNS)
1268 common:
1269 #endif
1270 		/* Fall through */
1271 
1272 	case NETCONS:
1273 	case TFTPSRV:
1274 		if (NetOurIP == 0) {
1275 			puts("*** ERROR: `ipaddr' not set\n");
1276 			return 1;
1277 		}
1278 		/* Fall through */
1279 
1280 #ifdef CONFIG_CMD_RARP
1281 	case RARP:
1282 #endif
1283 	case BOOTP:
1284 	case CDP:
1285 	case DHCP:
1286 	case LINKLOCAL:
1287 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1288 			int num = eth_get_dev_index();
1289 
1290 			switch (num) {
1291 			case -1:
1292 				puts("*** ERROR: No ethernet found.\n");
1293 				return 1;
1294 			case 0:
1295 				puts("*** ERROR: `ethaddr' not set\n");
1296 				break;
1297 			default:
1298 				printf("*** ERROR: `eth%daddr' not set\n",
1299 					num);
1300 				break;
1301 			}
1302 
1303 			NetStartAgain();
1304 			return 2;
1305 		}
1306 		/* Fall through */
1307 	default:
1308 		return 0;
1309 	}
1310 	return 0;		/* OK */
1311 }
1312 /**********************************************************************/
1313 
1314 int
1315 NetEthHdrSize(void)
1316 {
1317 	ushort myvlanid;
1318 
1319 	myvlanid = ntohs(NetOurVLAN);
1320 	if (myvlanid == (ushort)-1)
1321 		myvlanid = VLAN_NONE;
1322 
1323 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1324 		VLAN_ETHER_HDR_SIZE;
1325 }
1326 
1327 int
1328 NetSetEther(uchar *xet, uchar * addr, uint prot)
1329 {
1330 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1331 	ushort myvlanid;
1332 
1333 	myvlanid = ntohs(NetOurVLAN);
1334 	if (myvlanid == (ushort)-1)
1335 		myvlanid = VLAN_NONE;
1336 
1337 	memcpy(et->et_dest, addr, 6);
1338 	memcpy(et->et_src, NetOurEther, 6);
1339 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1340 		et->et_protlen = htons(prot);
1341 		return ETHER_HDR_SIZE;
1342 	} else {
1343 		struct vlan_ethernet_hdr *vet =
1344 			(struct vlan_ethernet_hdr *)xet;
1345 
1346 		vet->vet_vlan_type = htons(PROT_VLAN);
1347 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1348 		vet->vet_type = htons(prot);
1349 		return VLAN_ETHER_HDR_SIZE;
1350 	}
1351 }
1352 
1353 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1354 {
1355 	ushort protlen;
1356 
1357 	memcpy(et->et_dest, addr, 6);
1358 	memcpy(et->et_src, NetOurEther, 6);
1359 	protlen = ntohs(et->et_protlen);
1360 	if (protlen == PROT_VLAN) {
1361 		struct vlan_ethernet_hdr *vet =
1362 			(struct vlan_ethernet_hdr *)et;
1363 		vet->vet_type = htons(prot);
1364 		return VLAN_ETHER_HDR_SIZE;
1365 	} else if (protlen > 1514) {
1366 		et->et_protlen = htons(prot);
1367 		return ETHER_HDR_SIZE;
1368 	} else {
1369 		/* 802.2 + SNAP */
1370 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1371 		et802->et_prot = htons(prot);
1372 		return E802_HDR_SIZE;
1373 	}
1374 }
1375 
1376 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1377 {
1378 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1379 
1380 	/*
1381 	 *	Construct an IP header.
1382 	 */
1383 	/* IP_HDR_SIZE / 4 (not including UDP) */
1384 	ip->ip_hl_v  = 0x45;
1385 	ip->ip_tos   = 0;
1386 	ip->ip_len   = htons(IP_HDR_SIZE);
1387 	ip->ip_id    = htons(NetIPID++);
1388 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1389 	ip->ip_ttl   = 255;
1390 	ip->ip_sum   = 0;
1391 	/* already in network byte order */
1392 	NetCopyIP((void *)&ip->ip_src, &source);
1393 	/* already in network byte order */
1394 	NetCopyIP((void *)&ip->ip_dst, &dest);
1395 }
1396 
1397 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1398 			int len)
1399 {
1400 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1401 
1402 	/*
1403 	 *	If the data is an odd number of bytes, zero the
1404 	 *	byte after the last byte so that the checksum
1405 	 *	will work.
1406 	 */
1407 	if (len & 1)
1408 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1409 
1410 	net_set_ip_header(pkt, dest, NetOurIP);
1411 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1412 	ip->ip_p     = IPPROTO_UDP;
1413 	ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
1414 
1415 	ip->udp_src  = htons(sport);
1416 	ip->udp_dst  = htons(dport);
1417 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1418 	ip->udp_xsum = 0;
1419 }
1420 
1421 void copy_filename(char *dst, const char *src, int size)
1422 {
1423 	if (*src && (*src == '"')) {
1424 		++src;
1425 		--size;
1426 	}
1427 
1428 	while ((--size > 0) && *src && (*src != '"'))
1429 		*dst++ = *src++;
1430 	*dst = '\0';
1431 }
1432 
1433 #if	defined(CONFIG_CMD_NFS)		|| \
1434 	defined(CONFIG_CMD_SNTP)	|| \
1435 	defined(CONFIG_CMD_DNS)
1436 /*
1437  * make port a little random (1024-17407)
1438  * This keeps the math somewhat trivial to compute, and seems to work with
1439  * all supported protocols/clients/servers
1440  */
1441 unsigned int random_port(void)
1442 {
1443 	return 1024 + (get_timer(0) % 0x4000);
1444 }
1445 #endif
1446 
1447 void ip_to_string(IPaddr_t x, char *s)
1448 {
1449 	x = ntohl(x);
1450 	sprintf(s, "%d.%d.%d.%d",
1451 		(int) ((x >> 24) & 0xff),
1452 		(int) ((x >> 16) & 0xff),
1453 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1454 	);
1455 }
1456 
1457 void VLAN_to_string(ushort x, char *s)
1458 {
1459 	x = ntohs(x);
1460 
1461 	if (x == (ushort)-1)
1462 		x = VLAN_NONE;
1463 
1464 	if (x == VLAN_NONE)
1465 		strcpy(s, "none");
1466 	else
1467 		sprintf(s, "%d", x & VLAN_IDMASK);
1468 }
1469 
1470 ushort string_to_VLAN(const char *s)
1471 {
1472 	ushort id;
1473 
1474 	if (s == NULL)
1475 		return htons(VLAN_NONE);
1476 
1477 	if (*s < '0' || *s > '9')
1478 		id = VLAN_NONE;
1479 	else
1480 		id = (ushort)simple_strtoul(s, NULL, 10);
1481 
1482 	return htons(id);
1483 }
1484 
1485 ushort getenv_VLAN(char *var)
1486 {
1487 	return string_to_VLAN(getenv(var));
1488 }
1489