xref: /openbmc/u-boot/net/net.c (revision bf48fcb6)
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 				char buf[20];
532 				printf("Bytes transferred = %ld (%lx hex)\n",
533 					NetBootFileXferSize,
534 					NetBootFileXferSize);
535 				sprintf(buf, "%lX", NetBootFileXferSize);
536 				setenv("filesize", buf);
537 
538 				sprintf(buf, "%lX", (unsigned long)load_addr);
539 				setenv("fileaddr", buf);
540 			}
541 			if (protocol != NETCONS)
542 				eth_halt();
543 			else
544 				eth_halt_state_only();
545 
546 			eth_set_last_protocol(protocol);
547 
548 			ret = NetBootFileXferSize;
549 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
550 			goto done;
551 
552 		case NETLOOP_FAIL:
553 			net_cleanup_loop();
554 			/* Invalidate the last protocol */
555 			eth_set_last_protocol(BOOTP);
556 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
557 			goto done;
558 
559 		case NETLOOP_CONTINUE:
560 			continue;
561 		}
562 	}
563 
564 done:
565 #ifdef CONFIG_CMD_TFTPPUT
566 	/* Clear out the handlers */
567 	net_set_udp_handler(NULL);
568 	net_set_icmp_handler(NULL);
569 #endif
570 	return ret;
571 }
572 
573 /**********************************************************************/
574 
575 static void
576 startAgainTimeout(void)
577 {
578 	net_set_state(NETLOOP_RESTART);
579 }
580 
581 void NetStartAgain(void)
582 {
583 	char *nretry;
584 	int retry_forever = 0;
585 	unsigned long retrycnt = 0;
586 
587 	nretry = getenv("netretry");
588 	if (nretry) {
589 		if (!strcmp(nretry, "yes"))
590 			retry_forever = 1;
591 		else if (!strcmp(nretry, "no"))
592 			retrycnt = 0;
593 		else if (!strcmp(nretry, "once"))
594 			retrycnt = 1;
595 		else
596 			retrycnt = simple_strtoul(nretry, NULL, 0);
597 	} else
598 		retry_forever = 1;
599 
600 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
601 		eth_halt();
602 		net_set_state(NETLOOP_FAIL);
603 		return;
604 	}
605 
606 	NetTryCount++;
607 
608 	eth_halt();
609 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
610 	eth_try_another(!NetRestarted);
611 #endif
612 	eth_init(gd->bd);
613 	if (NetRestartWrap) {
614 		NetRestartWrap = 0;
615 		if (NetDevExists) {
616 			NetSetTimeout(10000UL, startAgainTimeout);
617 			net_set_udp_handler(NULL);
618 		} else {
619 			net_set_state(NETLOOP_FAIL);
620 		}
621 	} else {
622 		net_set_state(NETLOOP_RESTART);
623 	}
624 }
625 
626 /**********************************************************************/
627 /*
628  *	Miscelaneous bits.
629  */
630 
631 static void dummy_handler(uchar *pkt, unsigned dport,
632 			IPaddr_t sip, unsigned sport,
633 			unsigned len)
634 {
635 }
636 
637 rxhand_f *net_get_udp_handler(void)
638 {
639 	return udp_packet_handler;
640 }
641 
642 void net_set_udp_handler(rxhand_f *f)
643 {
644 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
645 	if (f == NULL)
646 		udp_packet_handler = dummy_handler;
647 	else
648 		udp_packet_handler = f;
649 }
650 
651 rxhand_f *net_get_arp_handler(void)
652 {
653 	return arp_packet_handler;
654 }
655 
656 void net_set_arp_handler(rxhand_f *f)
657 {
658 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
659 	if (f == NULL)
660 		arp_packet_handler = dummy_handler;
661 	else
662 		arp_packet_handler = f;
663 }
664 
665 #ifdef CONFIG_CMD_TFTPPUT
666 void net_set_icmp_handler(rxhand_icmp_f *f)
667 {
668 	packet_icmp_handler = f;
669 }
670 #endif
671 
672 void
673 NetSetTimeout(ulong iv, thand_f *f)
674 {
675 	if (iv == 0) {
676 		debug_cond(DEBUG_INT_STATE,
677 			"--- NetLoop timeout handler cancelled\n");
678 		timeHandler = (thand_f *)0;
679 	} else {
680 		debug_cond(DEBUG_INT_STATE,
681 			"--- NetLoop timeout handler set (%p)\n", f);
682 		timeHandler = f;
683 		timeStart = get_timer(0);
684 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
685 	}
686 }
687 
688 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
689 		int payload_len)
690 {
691 	uchar *pkt;
692 	int eth_hdr_size;
693 	int pkt_hdr_size;
694 
695 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
696 	assert(NetTxPacket != NULL);
697 	if (NetTxPacket == NULL)
698 		return -1;
699 
700 	/* convert to new style broadcast */
701 	if (dest == 0)
702 		dest = 0xFFFFFFFF;
703 
704 	/* if broadcast, make the ether address a broadcast and don't do ARP */
705 	if (dest == 0xFFFFFFFF)
706 		ether = NetBcastAddr;
707 
708 	pkt = (uchar *)NetTxPacket;
709 
710 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
711 	pkt += eth_hdr_size;
712 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
713 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
714 
715 	/* if MAC address was not discovered yet, do an ARP request */
716 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
717 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
718 
719 		/* save the ip and eth addr for the packet to send after arp */
720 		NetArpWaitPacketIP = dest;
721 		NetArpWaitPacketMAC = ether;
722 
723 		/* size of the waiting packet */
724 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
725 
726 		/* and do the ARP request */
727 		NetArpWaitTry = 1;
728 		NetArpWaitTimerStart = get_timer(0);
729 		ArpRequest();
730 		return 1;	/* waiting */
731 	} else {
732 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
733 			&dest, ether);
734 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
735 		return 0;	/* transmitted */
736 	}
737 }
738 
739 #ifdef CONFIG_IP_DEFRAG
740 /*
741  * This function collects fragments in a single packet, according
742  * to the algorithm in RFC815. It returns NULL or the pointer to
743  * a complete packet, in static storage
744  */
745 #ifndef CONFIG_NET_MAXDEFRAG
746 #define CONFIG_NET_MAXDEFRAG 16384
747 #endif
748 /*
749  * MAXDEFRAG, above, is chosen in the config file and  is real data
750  * so we need to add the NFS overhead, which is more than TFTP.
751  * To use sizeof in the internal unnamed structures, we need a real
752  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
753  * The compiler doesn't complain nor allocates the actual structure
754  */
755 static struct rpc_t rpc_specimen;
756 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
757 
758 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
759 
760 /*
761  * this is the packet being assembled, either data or frag control.
762  * Fragments go by 8 bytes, so this union must be 8 bytes long
763  */
764 struct hole {
765 	/* first_byte is address of this structure */
766 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
767 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
768 	u16 prev_hole;	/* index of prev, 0 == none */
769 	u16 unused;
770 };
771 
772 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
773 {
774 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
775 	static u16 first_hole, total_len;
776 	struct hole *payload, *thisfrag, *h, *newh;
777 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
778 	uchar *indata = (uchar *)ip;
779 	int offset8, start, len, done = 0;
780 	u16 ip_off = ntohs(ip->ip_off);
781 
782 	/* payload starts after IP header, this fragment is in there */
783 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
784 	offset8 =  (ip_off & IP_OFFS);
785 	thisfrag = payload + offset8;
786 	start = offset8 * 8;
787 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
788 
789 	if (start + len > IP_MAXUDP) /* fragment extends too far */
790 		return NULL;
791 
792 	if (!total_len || localip->ip_id != ip->ip_id) {
793 		/* new (or different) packet, reset structs */
794 		total_len = 0xffff;
795 		payload[0].last_byte = ~0;
796 		payload[0].next_hole = 0;
797 		payload[0].prev_hole = 0;
798 		first_hole = 0;
799 		/* any IP header will work, copy the first we received */
800 		memcpy(localip, ip, IP_HDR_SIZE);
801 	}
802 
803 	/*
804 	 * What follows is the reassembly algorithm. We use the payload
805 	 * array as a linked list of hole descriptors, as each hole starts
806 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
807 	 * so it is represented as byte count, not as 8-byte blocks.
808 	 */
809 
810 	h = payload + first_hole;
811 	while (h->last_byte < start) {
812 		if (!h->next_hole) {
813 			/* no hole that far away */
814 			return NULL;
815 		}
816 		h = payload + h->next_hole;
817 	}
818 
819 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
820 	if (offset8 + ((len + 7) / 8) <= h - payload) {
821 		/* no overlap with holes (dup fragment?) */
822 		return NULL;
823 	}
824 
825 	if (!(ip_off & IP_FLAGS_MFRAG)) {
826 		/* no more fragmentss: truncate this (last) hole */
827 		total_len = start + len;
828 		h->last_byte = start + len;
829 	}
830 
831 	/*
832 	 * There is some overlap: fix the hole list. This code doesn't
833 	 * deal with a fragment that overlaps with two different holes
834 	 * (thus being a superset of a previously-received fragment).
835 	 */
836 
837 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
838 		/* complete overlap with hole: remove hole */
839 		if (!h->prev_hole && !h->next_hole) {
840 			/* last remaining hole */
841 			done = 1;
842 		} else if (!h->prev_hole) {
843 			/* first hole */
844 			first_hole = h->next_hole;
845 			payload[h->next_hole].prev_hole = 0;
846 		} else if (!h->next_hole) {
847 			/* last hole */
848 			payload[h->prev_hole].next_hole = 0;
849 		} else {
850 			/* in the middle of the list */
851 			payload[h->next_hole].prev_hole = h->prev_hole;
852 			payload[h->prev_hole].next_hole = h->next_hole;
853 		}
854 
855 	} else if (h->last_byte <= start + len) {
856 		/* overlaps with final part of the hole: shorten this hole */
857 		h->last_byte = start;
858 
859 	} else if (h >= thisfrag) {
860 		/* overlaps with initial part of the hole: move this hole */
861 		newh = thisfrag + (len / 8);
862 		*newh = *h;
863 		h = newh;
864 		if (h->next_hole)
865 			payload[h->next_hole].prev_hole = (h - payload);
866 		if (h->prev_hole)
867 			payload[h->prev_hole].next_hole = (h - payload);
868 		else
869 			first_hole = (h - payload);
870 
871 	} else {
872 		/* fragment sits in the middle: split the hole */
873 		newh = thisfrag + (len / 8);
874 		*newh = *h;
875 		h->last_byte = start;
876 		h->next_hole = (newh - payload);
877 		newh->prev_hole = (h - payload);
878 		if (newh->next_hole)
879 			payload[newh->next_hole].prev_hole = (newh - payload);
880 	}
881 
882 	/* finally copy this fragment and possibly return whole packet */
883 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
884 	if (!done)
885 		return NULL;
886 
887 	localip->ip_len = htons(total_len);
888 	*lenp = total_len + IP_HDR_SIZE;
889 	return localip;
890 }
891 
892 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
893 {
894 	u16 ip_off = ntohs(ip->ip_off);
895 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
896 		return ip; /* not a fragment */
897 	return __NetDefragment(ip, lenp);
898 }
899 
900 #else /* !CONFIG_IP_DEFRAG */
901 
902 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
903 {
904 	u16 ip_off = ntohs(ip->ip_off);
905 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
906 		return ip; /* not a fragment */
907 	return NULL;
908 }
909 #endif
910 
911 /**
912  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
913  * drop others.
914  *
915  * @parma ip	IP packet containing the ICMP
916  */
917 static void receive_icmp(struct ip_udp_hdr *ip, int len,
918 			IPaddr_t src_ip, struct ethernet_hdr *et)
919 {
920 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
921 
922 	switch (icmph->type) {
923 	case ICMP_REDIRECT:
924 		if (icmph->code != ICMP_REDIR_HOST)
925 			return;
926 		printf(" ICMP Host Redirect to %pI4 ",
927 			&icmph->un.gateway);
928 		break;
929 	default:
930 #if defined(CONFIG_CMD_PING)
931 		ping_receive(et, ip, len);
932 #endif
933 #ifdef CONFIG_CMD_TFTPPUT
934 		if (packet_icmp_handler)
935 			packet_icmp_handler(icmph->type, icmph->code,
936 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
937 				icmph->un.data, ntohs(ip->udp_len));
938 #endif
939 		break;
940 	}
941 }
942 
943 void
944 NetReceive(uchar *inpkt, int len)
945 {
946 	struct ethernet_hdr *et;
947 	struct ip_udp_hdr *ip;
948 	IPaddr_t dst_ip;
949 	IPaddr_t src_ip;
950 	int eth_proto;
951 #if defined(CONFIG_CMD_CDP)
952 	int iscdp;
953 #endif
954 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
955 
956 	debug_cond(DEBUG_NET_PKT, "packet received\n");
957 
958 	NetRxPacket = inpkt;
959 	NetRxPacketLen = len;
960 	et = (struct ethernet_hdr *)inpkt;
961 
962 	/* too small packet? */
963 	if (len < ETHER_HDR_SIZE)
964 		return;
965 
966 #ifdef CONFIG_API
967 	if (push_packet) {
968 		(*push_packet)(inpkt, len);
969 		return;
970 	}
971 #endif
972 
973 #if defined(CONFIG_CMD_CDP)
974 	/* keep track if packet is CDP */
975 	iscdp = is_cdp_packet(et->et_dest);
976 #endif
977 
978 	myvlanid = ntohs(NetOurVLAN);
979 	if (myvlanid == (ushort)-1)
980 		myvlanid = VLAN_NONE;
981 	mynvlanid = ntohs(NetOurNativeVLAN);
982 	if (mynvlanid == (ushort)-1)
983 		mynvlanid = VLAN_NONE;
984 
985 	eth_proto = ntohs(et->et_protlen);
986 
987 	if (eth_proto < 1514) {
988 		struct e802_hdr *et802 = (struct e802_hdr *)et;
989 		/*
990 		 *	Got a 802.2 packet.  Check the other protocol field.
991 		 *	XXX VLAN over 802.2+SNAP not implemented!
992 		 */
993 		eth_proto = ntohs(et802->et_prot);
994 
995 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
996 		len -= E802_HDR_SIZE;
997 
998 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
999 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
1000 		len -= ETHER_HDR_SIZE;
1001 
1002 	} else {			/* VLAN packet */
1003 		struct vlan_ethernet_hdr *vet =
1004 			(struct vlan_ethernet_hdr *)et;
1005 
1006 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1007 
1008 		/* too small packet? */
1009 		if (len < VLAN_ETHER_HDR_SIZE)
1010 			return;
1011 
1012 		/* if no VLAN active */
1013 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1014 #if defined(CONFIG_CMD_CDP)
1015 				&& iscdp == 0
1016 #endif
1017 				)
1018 			return;
1019 
1020 		cti = ntohs(vet->vet_tag);
1021 		vlanid = cti & VLAN_IDMASK;
1022 		eth_proto = ntohs(vet->vet_type);
1023 
1024 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1025 		len -= VLAN_ETHER_HDR_SIZE;
1026 	}
1027 
1028 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1029 
1030 #if defined(CONFIG_CMD_CDP)
1031 	if (iscdp) {
1032 		cdp_receive((uchar *)ip, len);
1033 		return;
1034 	}
1035 #endif
1036 
1037 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1038 		if (vlanid == VLAN_NONE)
1039 			vlanid = (mynvlanid & VLAN_IDMASK);
1040 		/* not matched? */
1041 		if (vlanid != (myvlanid & VLAN_IDMASK))
1042 			return;
1043 	}
1044 
1045 	switch (eth_proto) {
1046 
1047 	case PROT_ARP:
1048 		ArpReceive(et, ip, len);
1049 		break;
1050 
1051 #ifdef CONFIG_CMD_RARP
1052 	case PROT_RARP:
1053 		rarp_receive(ip, len);
1054 		break;
1055 #endif
1056 	case PROT_IP:
1057 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1058 		/* Before we start poking the header, make sure it is there */
1059 		if (len < IP_UDP_HDR_SIZE) {
1060 			debug("len bad %d < %lu\n", len,
1061 				(ulong)IP_UDP_HDR_SIZE);
1062 			return;
1063 		}
1064 		/* Check the packet length */
1065 		if (len < ntohs(ip->ip_len)) {
1066 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1067 			return;
1068 		}
1069 		len = ntohs(ip->ip_len);
1070 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1071 			len, ip->ip_hl_v & 0xff);
1072 
1073 		/* Can't deal with anything except IPv4 */
1074 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1075 			return;
1076 		/* Can't deal with IP options (headers != 20 bytes) */
1077 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1078 			return;
1079 		/* Check the Checksum of the header */
1080 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1081 			debug("checksum bad\n");
1082 			return;
1083 		}
1084 		/* If it is not for us, ignore it */
1085 		dst_ip = NetReadIP(&ip->ip_dst);
1086 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1087 #ifdef CONFIG_MCAST_TFTP
1088 			if (Mcast_addr != dst_ip)
1089 #endif
1090 				return;
1091 		}
1092 		/* Read source IP address for later use */
1093 		src_ip = NetReadIP(&ip->ip_src);
1094 		/*
1095 		 * The function returns the unchanged packet if it's not
1096 		 * a fragment, and either the complete packet or NULL if
1097 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1098 		 */
1099 		ip = NetDefragment(ip, &len);
1100 		if (!ip)
1101 			return;
1102 		/*
1103 		 * watch for ICMP host redirects
1104 		 *
1105 		 * There is no real handler code (yet). We just watch
1106 		 * for ICMP host redirect messages. In case anybody
1107 		 * sees these messages: please contact me
1108 		 * (wd@denx.de), or - even better - send me the
1109 		 * necessary fixes :-)
1110 		 *
1111 		 * Note: in all cases where I have seen this so far
1112 		 * it was a problem with the router configuration,
1113 		 * for instance when a router was configured in the
1114 		 * BOOTP reply, but the TFTP server was on the same
1115 		 * subnet. So this is probably a warning that your
1116 		 * configuration might be wrong. But I'm not really
1117 		 * sure if there aren't any other situations.
1118 		 *
1119 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1120 		 * we send a tftp packet to a dead connection, or when
1121 		 * there is no server at the other end.
1122 		 */
1123 		if (ip->ip_p == IPPROTO_ICMP) {
1124 			receive_icmp(ip, len, src_ip, et);
1125 			return;
1126 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1127 			return;
1128 		}
1129 
1130 		debug_cond(DEBUG_DEV_PKT,
1131 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1132 			&dst_ip, &src_ip, len);
1133 
1134 #ifdef CONFIG_UDP_CHECKSUM
1135 		if (ip->udp_xsum != 0) {
1136 			ulong   xsum;
1137 			ushort *sumptr;
1138 			ushort  sumlen;
1139 
1140 			xsum  = ip->ip_p;
1141 			xsum += (ntohs(ip->udp_len));
1142 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1143 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1144 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1145 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1146 
1147 			sumlen = ntohs(ip->udp_len);
1148 			sumptr = (ushort *) &(ip->udp_src);
1149 
1150 			while (sumlen > 1) {
1151 				ushort sumdata;
1152 
1153 				sumdata = *sumptr++;
1154 				xsum += ntohs(sumdata);
1155 				sumlen -= 2;
1156 			}
1157 			if (sumlen > 0) {
1158 				ushort sumdata;
1159 
1160 				sumdata = *(unsigned char *) sumptr;
1161 				sumdata = (sumdata << 8) & 0xff00;
1162 				xsum += sumdata;
1163 			}
1164 			while ((xsum >> 16) != 0) {
1165 				xsum = (xsum & 0x0000ffff) +
1166 				       ((xsum >> 16) & 0x0000ffff);
1167 			}
1168 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1169 				printf(" UDP wrong checksum %08lx %08x\n",
1170 					xsum, ntohs(ip->udp_xsum));
1171 				return;
1172 			}
1173 		}
1174 #endif
1175 
1176 
1177 #ifdef CONFIG_NETCONSOLE
1178 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1179 					src_ip,
1180 					ntohs(ip->udp_dst),
1181 					ntohs(ip->udp_src),
1182 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1183 #endif
1184 		/*
1185 		 *	IP header OK.  Pass the packet to the current handler.
1186 		 */
1187 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1188 				ntohs(ip->udp_dst),
1189 				src_ip,
1190 				ntohs(ip->udp_src),
1191 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1192 		break;
1193 	}
1194 }
1195 
1196 
1197 /**********************************************************************/
1198 
1199 static int net_check_prereq(enum proto_t protocol)
1200 {
1201 	switch (protocol) {
1202 		/* Fall through */
1203 #if defined(CONFIG_CMD_PING)
1204 	case PING:
1205 		if (NetPingIP == 0) {
1206 			puts("*** ERROR: ping address not given\n");
1207 			return 1;
1208 		}
1209 		goto common;
1210 #endif
1211 #if defined(CONFIG_CMD_SNTP)
1212 	case SNTP:
1213 		if (NetNtpServerIP == 0) {
1214 			puts("*** ERROR: NTP server address not given\n");
1215 			return 1;
1216 		}
1217 		goto common;
1218 #endif
1219 #if defined(CONFIG_CMD_DNS)
1220 	case DNS:
1221 		if (NetOurDNSIP == 0) {
1222 			puts("*** ERROR: DNS server address not given\n");
1223 			return 1;
1224 		}
1225 		goto common;
1226 #endif
1227 #if defined(CONFIG_CMD_NFS)
1228 	case NFS:
1229 #endif
1230 	case TFTPGET:
1231 	case TFTPPUT:
1232 		if (NetServerIP == 0) {
1233 			puts("*** ERROR: `serverip' not set\n");
1234 			return 1;
1235 		}
1236 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1237 	defined(CONFIG_CMD_DNS)
1238 common:
1239 #endif
1240 		/* Fall through */
1241 
1242 	case NETCONS:
1243 	case TFTPSRV:
1244 		if (NetOurIP == 0) {
1245 			puts("*** ERROR: `ipaddr' not set\n");
1246 			return 1;
1247 		}
1248 		/* Fall through */
1249 
1250 #ifdef CONFIG_CMD_RARP
1251 	case RARP:
1252 #endif
1253 	case BOOTP:
1254 	case CDP:
1255 	case DHCP:
1256 	case LINKLOCAL:
1257 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1258 			int num = eth_get_dev_index();
1259 
1260 			switch (num) {
1261 			case -1:
1262 				puts("*** ERROR: No ethernet found.\n");
1263 				return 1;
1264 			case 0:
1265 				puts("*** ERROR: `ethaddr' not set\n");
1266 				break;
1267 			default:
1268 				printf("*** ERROR: `eth%daddr' not set\n",
1269 					num);
1270 				break;
1271 			}
1272 
1273 			NetStartAgain();
1274 			return 2;
1275 		}
1276 		/* Fall through */
1277 	default:
1278 		return 0;
1279 	}
1280 	return 0;		/* OK */
1281 }
1282 /**********************************************************************/
1283 
1284 int
1285 NetCksumOk(uchar *ptr, int len)
1286 {
1287 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1288 }
1289 
1290 
1291 unsigned
1292 NetCksum(uchar *ptr, int len)
1293 {
1294 	ulong	xsum;
1295 	ushort *p = (ushort *)ptr;
1296 
1297 	xsum = 0;
1298 	while (len-- > 0)
1299 		xsum += *p++;
1300 	xsum = (xsum & 0xffff) + (xsum >> 16);
1301 	xsum = (xsum & 0xffff) + (xsum >> 16);
1302 	return xsum & 0xffff;
1303 }
1304 
1305 int
1306 NetEthHdrSize(void)
1307 {
1308 	ushort myvlanid;
1309 
1310 	myvlanid = ntohs(NetOurVLAN);
1311 	if (myvlanid == (ushort)-1)
1312 		myvlanid = VLAN_NONE;
1313 
1314 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1315 		VLAN_ETHER_HDR_SIZE;
1316 }
1317 
1318 int
1319 NetSetEther(uchar *xet, uchar * addr, uint prot)
1320 {
1321 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1322 	ushort myvlanid;
1323 
1324 	myvlanid = ntohs(NetOurVLAN);
1325 	if (myvlanid == (ushort)-1)
1326 		myvlanid = VLAN_NONE;
1327 
1328 	memcpy(et->et_dest, addr, 6);
1329 	memcpy(et->et_src, NetOurEther, 6);
1330 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1331 		et->et_protlen = htons(prot);
1332 		return ETHER_HDR_SIZE;
1333 	} else {
1334 		struct vlan_ethernet_hdr *vet =
1335 			(struct vlan_ethernet_hdr *)xet;
1336 
1337 		vet->vet_vlan_type = htons(PROT_VLAN);
1338 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1339 		vet->vet_type = htons(prot);
1340 		return VLAN_ETHER_HDR_SIZE;
1341 	}
1342 }
1343 
1344 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1345 {
1346 	ushort protlen;
1347 
1348 	memcpy(et->et_dest, addr, 6);
1349 	memcpy(et->et_src, NetOurEther, 6);
1350 	protlen = ntohs(et->et_protlen);
1351 	if (protlen == PROT_VLAN) {
1352 		struct vlan_ethernet_hdr *vet =
1353 			(struct vlan_ethernet_hdr *)et;
1354 		vet->vet_type = htons(prot);
1355 		return VLAN_ETHER_HDR_SIZE;
1356 	} else if (protlen > 1514) {
1357 		et->et_protlen = htons(prot);
1358 		return ETHER_HDR_SIZE;
1359 	} else {
1360 		/* 802.2 + SNAP */
1361 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1362 		et802->et_prot = htons(prot);
1363 		return E802_HDR_SIZE;
1364 	}
1365 }
1366 
1367 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1368 {
1369 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1370 
1371 	/*
1372 	 *	Construct an IP header.
1373 	 */
1374 	/* IP_HDR_SIZE / 4 (not including UDP) */
1375 	ip->ip_hl_v  = 0x45;
1376 	ip->ip_tos   = 0;
1377 	ip->ip_len   = htons(IP_HDR_SIZE);
1378 	ip->ip_id    = htons(NetIPID++);
1379 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1380 	ip->ip_ttl   = 255;
1381 	ip->ip_sum   = 0;
1382 	/* already in network byte order */
1383 	NetCopyIP((void *)&ip->ip_src, &source);
1384 	/* already in network byte order */
1385 	NetCopyIP((void *)&ip->ip_dst, &dest);
1386 }
1387 
1388 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1389 			int len)
1390 {
1391 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1392 
1393 	/*
1394 	 *	If the data is an odd number of bytes, zero the
1395 	 *	byte after the last byte so that the checksum
1396 	 *	will work.
1397 	 */
1398 	if (len & 1)
1399 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1400 
1401 	net_set_ip_header(pkt, dest, NetOurIP);
1402 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1403 	ip->ip_p     = IPPROTO_UDP;
1404 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1405 
1406 	ip->udp_src  = htons(sport);
1407 	ip->udp_dst  = htons(dport);
1408 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1409 	ip->udp_xsum = 0;
1410 }
1411 
1412 void copy_filename(char *dst, const char *src, int size)
1413 {
1414 	if (*src && (*src == '"')) {
1415 		++src;
1416 		--size;
1417 	}
1418 
1419 	while ((--size > 0) && *src && (*src != '"'))
1420 		*dst++ = *src++;
1421 	*dst = '\0';
1422 }
1423 
1424 #if	defined(CONFIG_CMD_NFS)		|| \
1425 	defined(CONFIG_CMD_SNTP)	|| \
1426 	defined(CONFIG_CMD_DNS)
1427 /*
1428  * make port a little random (1024-17407)
1429  * This keeps the math somewhat trivial to compute, and seems to work with
1430  * all supported protocols/clients/servers
1431  */
1432 unsigned int random_port(void)
1433 {
1434 	return 1024 + (get_timer(0) % 0x4000);
1435 }
1436 #endif
1437 
1438 void ip_to_string(IPaddr_t x, char *s)
1439 {
1440 	x = ntohl(x);
1441 	sprintf(s, "%d.%d.%d.%d",
1442 		(int) ((x >> 24) & 0xff),
1443 		(int) ((x >> 16) & 0xff),
1444 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1445 	);
1446 }
1447 
1448 void VLAN_to_string(ushort x, char *s)
1449 {
1450 	x = ntohs(x);
1451 
1452 	if (x == (ushort)-1)
1453 		x = VLAN_NONE;
1454 
1455 	if (x == VLAN_NONE)
1456 		strcpy(s, "none");
1457 	else
1458 		sprintf(s, "%d", x & VLAN_IDMASK);
1459 }
1460 
1461 ushort string_to_VLAN(const char *s)
1462 {
1463 	ushort id;
1464 
1465 	if (s == NULL)
1466 		return htons(VLAN_NONE);
1467 
1468 	if (*s < '0' || *s > '9')
1469 		id = VLAN_NONE;
1470 	else
1471 		id = (ushort)simple_strtoul(s, NULL, 10);
1472 
1473 	return htons(id);
1474 }
1475 
1476 ushort getenv_VLAN(char *var)
1477 {
1478 	return string_to_VLAN(getenv(var));
1479 }
1480