xref: /openbmc/u-boot/net/net.c (revision 150c2493)
1 /*
2  *	Copied from Linux Monitor (LiMon) - Networking.
3  *
4  *	Copyright 1994 - 2000 Neil Russell.
5  *	(See License)
6  *	Copyright 2000 Roland Borde
7  *	Copyright 2000 Paolo Scaffardi
8  *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
9  */
10 
11 /*
12  * General Desription:
13  *
14  * The user interface supports commands for BOOTP, RARP, and TFTP.
15  * Also, we support ARP internally. Depending on available data,
16  * these interact as follows:
17  *
18  * BOOTP:
19  *
20  *	Prerequisites:	- own ethernet address
21  *	We want:	- own IP address
22  *			- TFTP server IP address
23  *			- name of bootfile
24  *	Next step:	ARP
25  *
26  * LINK_LOCAL:
27  *
28  *	Prerequisites:	- own ethernet address
29  *	We want:	- own IP address
30  *	Next step:	ARP
31  *
32  * RARP:
33  *
34  *	Prerequisites:	- own ethernet address
35  *	We want:	- own IP address
36  *			- TFTP server IP address
37  *	Next step:	ARP
38  *
39  * ARP:
40  *
41  *	Prerequisites:	- own ethernet address
42  *			- own IP address
43  *			- TFTP server IP address
44  *	We want:	- TFTP server ethernet address
45  *	Next step:	TFTP
46  *
47  * DHCP:
48  *
49  *     Prerequisites:	- own ethernet address
50  *     We want:		- IP, Netmask, ServerIP, Gateway IP
51  *			- bootfilename, lease time
52  *     Next step:	- TFTP
53  *
54  * TFTP:
55  *
56  *	Prerequisites:	- own ethernet address
57  *			- own IP address
58  *			- TFTP server IP address
59  *			- TFTP server ethernet address
60  *			- name of bootfile (if unknown, we use a default name
61  *			  derived from our own IP address)
62  *	We want:	- load the boot file
63  *	Next step:	none
64  *
65  * NFS:
66  *
67  *	Prerequisites:	- own ethernet address
68  *			- own IP address
69  *			- name of bootfile (if unknown, we use a default name
70  *			  derived from our own IP address)
71  *	We want:	- load the boot file
72  *	Next step:	none
73  *
74  * SNTP:
75  *
76  *	Prerequisites:	- own ethernet address
77  *			- own IP address
78  *	We want:	- network time
79  *	Next step:	none
80  */
81 
82 
83 #include <common.h>
84 #include <command.h>
85 #include <net.h>
86 #if defined(CONFIG_STATUS_LED)
87 #include <miiphy.h>
88 #include <status_led.h>
89 #endif
90 #include <watchdog.h>
91 #include <linux/compiler.h>
92 #include "arp.h"
93 #include "bootp.h"
94 #include "cdp.h"
95 #if defined(CONFIG_CMD_DNS)
96 #include "dns.h"
97 #endif
98 #include "link_local.h"
99 #include "nfs.h"
100 #include "ping.h"
101 #include "rarp.h"
102 #if defined(CONFIG_CMD_SNTP)
103 #include "sntp.h"
104 #endif
105 #include "tftp.h"
106 
107 DECLARE_GLOBAL_DATA_PTR;
108 
109 /** BOOTP EXTENTIONS **/
110 
111 /* Our subnet mask (0=unknown) */
112 IPaddr_t	NetOurSubnetMask;
113 /* Our gateways IP address */
114 IPaddr_t	NetOurGatewayIP;
115 /* Our DNS IP address */
116 IPaddr_t	NetOurDNSIP;
117 #if defined(CONFIG_BOOTP_DNS2)
118 /* Our 2nd DNS IP address */
119 IPaddr_t	NetOurDNS2IP;
120 #endif
121 /* Our NIS domain */
122 char		NetOurNISDomain[32] = {0,};
123 /* Our hostname */
124 char		NetOurHostName[32] = {0,};
125 /* Our bootpath */
126 char		NetOurRootPath[64] = {0,};
127 /* Our bootfile size in blocks */
128 ushort		NetBootFileSize;
129 
130 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
131 IPaddr_t Mcast_addr;
132 #endif
133 
134 /** END OF BOOTP EXTENTIONS **/
135 
136 /* The actual transferred size of the bootfile (in bytes) */
137 ulong		NetBootFileXferSize;
138 /* Our ethernet address */
139 uchar		NetOurEther[6];
140 /* Boot server enet address */
141 uchar		NetServerEther[6];
142 /* Our IP addr (0 = unknown) */
143 IPaddr_t	NetOurIP;
144 /* Server IP addr (0 = unknown) */
145 IPaddr_t	NetServerIP;
146 /* Current receive packet */
147 uchar *NetRxPacket;
148 /* Current rx packet length */
149 int		NetRxPacketLen;
150 /* IP packet ID */
151 unsigned	NetIPID;
152 /* Ethernet bcast address */
153 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
154 uchar		NetEtherNullAddr[6];
155 #ifdef CONFIG_API
156 void		(*push_packet)(void *, int len) = 0;
157 #endif
158 /* Network loop state */
159 enum net_loop_state net_state;
160 /* Tried all network devices */
161 int		NetRestartWrap;
162 /* Network loop restarted */
163 static int	NetRestarted;
164 /* At least one device configured */
165 static int	NetDevExists;
166 
167 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
168 /* default is without VLAN */
169 ushort		NetOurVLAN = 0xFFFF;
170 /* ditto */
171 ushort		NetOurNativeVLAN = 0xFFFF;
172 
173 /* Boot File name */
174 char		BootFile[128];
175 
176 #if defined(CONFIG_CMD_SNTP)
177 /* NTP server IP address */
178 IPaddr_t	NetNtpServerIP;
179 /* offset time from UTC */
180 int		NetTimeOffset;
181 #endif
182 
183 uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
184 
185 /* Receive packet */
186 uchar *NetRxPackets[PKTBUFSRX];
187 
188 /* Current UDP RX packet handler */
189 static rxhand_f *udp_packet_handler;
190 /* Current ARP RX packet handler */
191 static rxhand_f *arp_packet_handler;
192 #ifdef CONFIG_CMD_TFTPPUT
193 /* Current ICMP rx handler */
194 static rxhand_icmp_f *packet_icmp_handler;
195 #endif
196 /* Current timeout handler */
197 static thand_f *timeHandler;
198 /* Time base value */
199 static ulong	timeStart;
200 /* Current timeout value */
201 static ulong	timeDelta;
202 /* THE transmit packet */
203 uchar *NetTxPacket;
204 
205 static int net_check_prereq(enum proto_t protocol);
206 
207 static int NetTryCount;
208 
209 /**********************************************************************/
210 
211 /*
212  * Check if autoload is enabled. If so, use either NFS or TFTP to download
213  * the boot file.
214  */
215 void net_auto_load(void)
216 {
217 	const char *s = getenv("autoload");
218 
219 	if (s != NULL) {
220 		if (*s == 'n') {
221 			/*
222 			 * Just use BOOTP/RARP to configure system;
223 			 * Do not use TFTP to load the bootfile.
224 			 */
225 			net_set_state(NETLOOP_SUCCESS);
226 			return;
227 		}
228 #if defined(CONFIG_CMD_NFS)
229 		if (strcmp(s, "NFS") == 0) {
230 			/*
231 			 * Use NFS to load the bootfile.
232 			 */
233 			NfsStart();
234 			return;
235 		}
236 #endif
237 	}
238 	TftpStart(TFTPGET);
239 }
240 
241 static void NetInitLoop(void)
242 {
243 	static int env_changed_id;
244 	int env_id = get_env_id();
245 
246 	/* update only when the environment has changed */
247 	if (env_changed_id != env_id) {
248 		NetOurIP = getenv_IPaddr("ipaddr");
249 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
250 		NetOurSubnetMask = getenv_IPaddr("netmask");
251 		NetServerIP = getenv_IPaddr("serverip");
252 		NetOurNativeVLAN = getenv_VLAN("nvlan");
253 		NetOurVLAN = getenv_VLAN("vlan");
254 #if defined(CONFIG_CMD_DNS)
255 		NetOurDNSIP = getenv_IPaddr("dnsip");
256 #endif
257 		env_changed_id = env_id;
258 	}
259 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
260 
261 	return;
262 }
263 
264 static void net_clear_handlers(void)
265 {
266 	net_set_udp_handler(NULL);
267 	net_set_arp_handler(NULL);
268 	NetSetTimeout(0, NULL);
269 }
270 
271 static void net_cleanup_loop(void)
272 {
273 	net_clear_handlers();
274 }
275 
276 void net_init(void)
277 {
278 	static int first_call = 1;
279 
280 	if (first_call) {
281 		/*
282 		 *	Setup packet buffers, aligned correctly.
283 		 */
284 		int i;
285 
286 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
287 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
288 		for (i = 0; i < PKTBUFSRX; i++)
289 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
290 
291 		ArpInit();
292 		net_clear_handlers();
293 
294 		/* Only need to setup buffer pointers once. */
295 		first_call = 0;
296 	}
297 
298 	NetInitLoop();
299 }
300 
301 /**********************************************************************/
302 /*
303  *	Main network processing loop.
304  */
305 
306 int NetLoop(enum proto_t protocol)
307 {
308 	bd_t *bd = gd->bd;
309 	int ret = -1;
310 
311 	NetRestarted = 0;
312 	NetDevExists = 0;
313 	NetTryCount = 1;
314 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
315 
316 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
317 	net_init();
318 	if (eth_is_on_demand_init() || protocol != NETCONS) {
319 		eth_halt();
320 		eth_set_current();
321 		if (eth_init(bd) < 0) {
322 			eth_halt();
323 			return -1;
324 		}
325 	} else
326 		eth_init_state_only(bd);
327 
328 restart:
329 	net_set_state(NETLOOP_CONTINUE);
330 
331 	/*
332 	 *	Start the ball rolling with the given start function.  From
333 	 *	here on, this code is a state machine driven by received
334 	 *	packets and timer events.
335 	 */
336 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
337 	NetInitLoop();
338 
339 	switch (net_check_prereq(protocol)) {
340 	case 1:
341 		/* network not configured */
342 		eth_halt();
343 		return -1;
344 
345 	case 2:
346 		/* network device not configured */
347 		break;
348 
349 	case 0:
350 		NetDevExists = 1;
351 		NetBootFileXferSize = 0;
352 		switch (protocol) {
353 		case TFTPGET:
354 #ifdef CONFIG_CMD_TFTPPUT
355 		case TFTPPUT:
356 #endif
357 			/* always use ARP to get server ethernet address */
358 			TftpStart(protocol);
359 			break;
360 #ifdef CONFIG_CMD_TFTPSRV
361 		case TFTPSRV:
362 			TftpStartServer();
363 			break;
364 #endif
365 #if defined(CONFIG_CMD_DHCP)
366 		case DHCP:
367 			BootpTry = 0;
368 			NetOurIP = 0;
369 			DhcpRequest();		/* Basically same as BOOTP */
370 			break;
371 #endif
372 
373 		case BOOTP:
374 			BootpTry = 0;
375 			NetOurIP = 0;
376 			BootpRequest();
377 			break;
378 
379 #if defined(CONFIG_CMD_RARP)
380 		case RARP:
381 			RarpTry = 0;
382 			NetOurIP = 0;
383 			RarpRequest();
384 			break;
385 #endif
386 #if defined(CONFIG_CMD_PING)
387 		case PING:
388 			ping_start();
389 			break;
390 #endif
391 #if defined(CONFIG_CMD_NFS)
392 		case NFS:
393 			NfsStart();
394 			break;
395 #endif
396 #if defined(CONFIG_CMD_CDP)
397 		case CDP:
398 			CDPStart();
399 			break;
400 #endif
401 #ifdef CONFIG_NETCONSOLE
402 		case NETCONS:
403 			NcStart();
404 			break;
405 #endif
406 #if defined(CONFIG_CMD_SNTP)
407 		case SNTP:
408 			SntpStart();
409 			break;
410 #endif
411 #if defined(CONFIG_CMD_DNS)
412 		case DNS:
413 			DnsStart();
414 			break;
415 #endif
416 #if defined(CONFIG_CMD_LINK_LOCAL)
417 		case LINKLOCAL:
418 			link_local_start();
419 			break;
420 #endif
421 		default:
422 			break;
423 		}
424 
425 		break;
426 	}
427 
428 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
429 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
430 	defined(CONFIG_STATUS_LED)			&& \
431 	defined(STATUS_LED_RED)
432 	/*
433 	 * Echo the inverted link state to the fault LED.
434 	 */
435 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
436 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
437 	else
438 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
439 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
440 #endif /* CONFIG_MII, ... */
441 
442 	/*
443 	 *	Main packet reception loop.  Loop receiving packets until
444 	 *	someone sets `net_state' to a state that terminates.
445 	 */
446 	for (;;) {
447 		WATCHDOG_RESET();
448 #ifdef CONFIG_SHOW_ACTIVITY
449 		show_activity(1);
450 #endif
451 		/*
452 		 *	Check the ethernet for a new packet.  The ethernet
453 		 *	receive routine will process it.
454 		 */
455 		eth_rx();
456 
457 		/*
458 		 *	Abort if ctrl-c was pressed.
459 		 */
460 		if (ctrlc()) {
461 			/* cancel any ARP that may not have completed */
462 			NetArpWaitPacketIP = 0;
463 
464 			net_cleanup_loop();
465 			eth_halt();
466 			/* Invalidate the last protocol */
467 			eth_set_last_protocol(BOOTP);
468 
469 			puts("\nAbort\n");
470 			/* include a debug print as well incase the debug
471 			   messages are directed to stderr */
472 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
473 			goto done;
474 		}
475 
476 		ArpTimeoutCheck();
477 
478 		/*
479 		 *	Check for a timeout, and run the timeout handler
480 		 *	if we have one.
481 		 */
482 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
483 			thand_f *x;
484 
485 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
486 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
487 	defined(CONFIG_STATUS_LED)			&& \
488 	defined(STATUS_LED_RED)
489 			/*
490 			 * Echo the inverted link state to the fault LED.
491 			 */
492 			if (miiphy_link(eth_get_dev()->name,
493 				       CONFIG_SYS_FAULT_MII_ADDR)) {
494 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
495 			} else {
496 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
497 			}
498 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
499 #endif /* CONFIG_MII, ... */
500 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
501 			x = timeHandler;
502 			timeHandler = (thand_f *)0;
503 			(*x)();
504 		}
505 
506 
507 		switch (net_state) {
508 
509 		case NETLOOP_RESTART:
510 			NetRestarted = 1;
511 			goto restart;
512 
513 		case NETLOOP_SUCCESS:
514 			net_cleanup_loop();
515 			if (NetBootFileXferSize > 0) {
516 				char buf[20];
517 				printf("Bytes transferred = %ld (%lx hex)\n",
518 					NetBootFileXferSize,
519 					NetBootFileXferSize);
520 				sprintf(buf, "%lX", NetBootFileXferSize);
521 				setenv("filesize", buf);
522 
523 				sprintf(buf, "%lX", (unsigned long)load_addr);
524 				setenv("fileaddr", buf);
525 			}
526 			if (protocol != NETCONS)
527 				eth_halt();
528 			else
529 				eth_halt_state_only();
530 
531 			eth_set_last_protocol(protocol);
532 
533 			ret = NetBootFileXferSize;
534 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
535 			goto done;
536 
537 		case NETLOOP_FAIL:
538 			net_cleanup_loop();
539 			/* Invalidate the last protocol */
540 			eth_set_last_protocol(BOOTP);
541 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
542 			goto done;
543 
544 		case NETLOOP_CONTINUE:
545 			continue;
546 		}
547 	}
548 
549 done:
550 #ifdef CONFIG_CMD_TFTPPUT
551 	/* Clear out the handlers */
552 	net_set_udp_handler(NULL);
553 	net_set_icmp_handler(NULL);
554 #endif
555 	return ret;
556 }
557 
558 /**********************************************************************/
559 
560 static void
561 startAgainTimeout(void)
562 {
563 	net_set_state(NETLOOP_RESTART);
564 }
565 
566 void NetStartAgain(void)
567 {
568 	char *nretry;
569 	int retry_forever = 0;
570 	unsigned long retrycnt = 0;
571 
572 	nretry = getenv("netretry");
573 	if (nretry) {
574 		if (!strcmp(nretry, "yes"))
575 			retry_forever = 1;
576 		else if (!strcmp(nretry, "no"))
577 			retrycnt = 0;
578 		else if (!strcmp(nretry, "once"))
579 			retrycnt = 1;
580 		else
581 			retrycnt = simple_strtoul(nretry, NULL, 0);
582 	} else
583 		retry_forever = 1;
584 
585 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
586 		eth_halt();
587 		net_set_state(NETLOOP_FAIL);
588 		return;
589 	}
590 
591 	NetTryCount++;
592 
593 	eth_halt();
594 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
595 	eth_try_another(!NetRestarted);
596 #endif
597 	eth_init(gd->bd);
598 	if (NetRestartWrap) {
599 		NetRestartWrap = 0;
600 		if (NetDevExists) {
601 			NetSetTimeout(10000UL, startAgainTimeout);
602 			net_set_udp_handler(NULL);
603 		} else {
604 			net_set_state(NETLOOP_FAIL);
605 		}
606 	} else {
607 		net_set_state(NETLOOP_RESTART);
608 	}
609 }
610 
611 /**********************************************************************/
612 /*
613  *	Miscelaneous bits.
614  */
615 
616 static void dummy_handler(uchar *pkt, unsigned dport,
617 			IPaddr_t sip, unsigned sport,
618 			unsigned len)
619 {
620 }
621 
622 rxhand_f *net_get_udp_handler(void)
623 {
624 	return udp_packet_handler;
625 }
626 
627 void net_set_udp_handler(rxhand_f *f)
628 {
629 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
630 	if (f == NULL)
631 		udp_packet_handler = dummy_handler;
632 	else
633 		udp_packet_handler = f;
634 }
635 
636 rxhand_f *net_get_arp_handler(void)
637 {
638 	return arp_packet_handler;
639 }
640 
641 void net_set_arp_handler(rxhand_f *f)
642 {
643 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
644 	if (f == NULL)
645 		arp_packet_handler = dummy_handler;
646 	else
647 		arp_packet_handler = f;
648 }
649 
650 #ifdef CONFIG_CMD_TFTPPUT
651 void net_set_icmp_handler(rxhand_icmp_f *f)
652 {
653 	packet_icmp_handler = f;
654 }
655 #endif
656 
657 void
658 NetSetTimeout(ulong iv, thand_f *f)
659 {
660 	if (iv == 0) {
661 		debug_cond(DEBUG_INT_STATE,
662 			"--- NetLoop timeout handler cancelled\n");
663 		timeHandler = (thand_f *)0;
664 	} else {
665 		debug_cond(DEBUG_INT_STATE,
666 			"--- NetLoop timeout handler set (%p)\n", f);
667 		timeHandler = f;
668 		timeStart = get_timer(0);
669 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
670 	}
671 }
672 
673 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
674 		int payload_len)
675 {
676 	uchar *pkt;
677 	int eth_hdr_size;
678 	int pkt_hdr_size;
679 
680 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
681 	assert(NetTxPacket != NULL);
682 	if (NetTxPacket == NULL)
683 		return -1;
684 
685 	/* convert to new style broadcast */
686 	if (dest == 0)
687 		dest = 0xFFFFFFFF;
688 
689 	/* if broadcast, make the ether address a broadcast and don't do ARP */
690 	if (dest == 0xFFFFFFFF)
691 		ether = NetBcastAddr;
692 
693 	pkt = (uchar *)NetTxPacket;
694 
695 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
696 	pkt += eth_hdr_size;
697 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
698 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
699 
700 	/* if MAC address was not discovered yet, do an ARP request */
701 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
702 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
703 
704 		/* save the ip and eth addr for the packet to send after arp */
705 		NetArpWaitPacketIP = dest;
706 		NetArpWaitPacketMAC = ether;
707 
708 		/* size of the waiting packet */
709 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
710 
711 		/* and do the ARP request */
712 		NetArpWaitTry = 1;
713 		NetArpWaitTimerStart = get_timer(0);
714 		ArpRequest();
715 		return 1;	/* waiting */
716 	} else {
717 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
718 			&dest, ether);
719 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
720 		return 0;	/* transmitted */
721 	}
722 }
723 
724 #ifdef CONFIG_IP_DEFRAG
725 /*
726  * This function collects fragments in a single packet, according
727  * to the algorithm in RFC815. It returns NULL or the pointer to
728  * a complete packet, in static storage
729  */
730 #ifndef CONFIG_NET_MAXDEFRAG
731 #define CONFIG_NET_MAXDEFRAG 16384
732 #endif
733 /*
734  * MAXDEFRAG, above, is chosen in the config file and  is real data
735  * so we need to add the NFS overhead, which is more than TFTP.
736  * To use sizeof in the internal unnamed structures, we need a real
737  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
738  * The compiler doesn't complain nor allocates the actual structure
739  */
740 static struct rpc_t rpc_specimen;
741 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
742 
743 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
744 
745 /*
746  * this is the packet being assembled, either data or frag control.
747  * Fragments go by 8 bytes, so this union must be 8 bytes long
748  */
749 struct hole {
750 	/* first_byte is address of this structure */
751 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
752 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
753 	u16 prev_hole;	/* index of prev, 0 == none */
754 	u16 unused;
755 };
756 
757 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
758 {
759 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
760 	static u16 first_hole, total_len;
761 	struct hole *payload, *thisfrag, *h, *newh;
762 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
763 	uchar *indata = (uchar *)ip;
764 	int offset8, start, len, done = 0;
765 	u16 ip_off = ntohs(ip->ip_off);
766 
767 	/* payload starts after IP header, this fragment is in there */
768 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
769 	offset8 =  (ip_off & IP_OFFS);
770 	thisfrag = payload + offset8;
771 	start = offset8 * 8;
772 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
773 
774 	if (start + len > IP_MAXUDP) /* fragment extends too far */
775 		return NULL;
776 
777 	if (!total_len || localip->ip_id != ip->ip_id) {
778 		/* new (or different) packet, reset structs */
779 		total_len = 0xffff;
780 		payload[0].last_byte = ~0;
781 		payload[0].next_hole = 0;
782 		payload[0].prev_hole = 0;
783 		first_hole = 0;
784 		/* any IP header will work, copy the first we received */
785 		memcpy(localip, ip, IP_HDR_SIZE);
786 	}
787 
788 	/*
789 	 * What follows is the reassembly algorithm. We use the payload
790 	 * array as a linked list of hole descriptors, as each hole starts
791 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
792 	 * so it is represented as byte count, not as 8-byte blocks.
793 	 */
794 
795 	h = payload + first_hole;
796 	while (h->last_byte < start) {
797 		if (!h->next_hole) {
798 			/* no hole that far away */
799 			return NULL;
800 		}
801 		h = payload + h->next_hole;
802 	}
803 
804 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
805 	if (offset8 + ((len + 7) / 8) <= h - payload) {
806 		/* no overlap with holes (dup fragment?) */
807 		return NULL;
808 	}
809 
810 	if (!(ip_off & IP_FLAGS_MFRAG)) {
811 		/* no more fragmentss: truncate this (last) hole */
812 		total_len = start + len;
813 		h->last_byte = start + len;
814 	}
815 
816 	/*
817 	 * There is some overlap: fix the hole list. This code doesn't
818 	 * deal with a fragment that overlaps with two different holes
819 	 * (thus being a superset of a previously-received fragment).
820 	 */
821 
822 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
823 		/* complete overlap with hole: remove hole */
824 		if (!h->prev_hole && !h->next_hole) {
825 			/* last remaining hole */
826 			done = 1;
827 		} else if (!h->prev_hole) {
828 			/* first hole */
829 			first_hole = h->next_hole;
830 			payload[h->next_hole].prev_hole = 0;
831 		} else if (!h->next_hole) {
832 			/* last hole */
833 			payload[h->prev_hole].next_hole = 0;
834 		} else {
835 			/* in the middle of the list */
836 			payload[h->next_hole].prev_hole = h->prev_hole;
837 			payload[h->prev_hole].next_hole = h->next_hole;
838 		}
839 
840 	} else if (h->last_byte <= start + len) {
841 		/* overlaps with final part of the hole: shorten this hole */
842 		h->last_byte = start;
843 
844 	} else if (h >= thisfrag) {
845 		/* overlaps with initial part of the hole: move this hole */
846 		newh = thisfrag + (len / 8);
847 		*newh = *h;
848 		h = newh;
849 		if (h->next_hole)
850 			payload[h->next_hole].prev_hole = (h - payload);
851 		if (h->prev_hole)
852 			payload[h->prev_hole].next_hole = (h - payload);
853 		else
854 			first_hole = (h - payload);
855 
856 	} else {
857 		/* fragment sits in the middle: split the hole */
858 		newh = thisfrag + (len / 8);
859 		*newh = *h;
860 		h->last_byte = start;
861 		h->next_hole = (newh - payload);
862 		newh->prev_hole = (h - payload);
863 		if (newh->next_hole)
864 			payload[newh->next_hole].prev_hole = (newh - payload);
865 	}
866 
867 	/* finally copy this fragment and possibly return whole packet */
868 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
869 	if (!done)
870 		return NULL;
871 
872 	localip->ip_len = htons(total_len);
873 	*lenp = total_len + IP_HDR_SIZE;
874 	return localip;
875 }
876 
877 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
878 {
879 	u16 ip_off = ntohs(ip->ip_off);
880 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
881 		return ip; /* not a fragment */
882 	return __NetDefragment(ip, lenp);
883 }
884 
885 #else /* !CONFIG_IP_DEFRAG */
886 
887 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
888 {
889 	u16 ip_off = ntohs(ip->ip_off);
890 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
891 		return ip; /* not a fragment */
892 	return NULL;
893 }
894 #endif
895 
896 /**
897  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
898  * drop others.
899  *
900  * @parma ip	IP packet containing the ICMP
901  */
902 static void receive_icmp(struct ip_udp_hdr *ip, int len,
903 			IPaddr_t src_ip, struct ethernet_hdr *et)
904 {
905 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
906 
907 	switch (icmph->type) {
908 	case ICMP_REDIRECT:
909 		if (icmph->code != ICMP_REDIR_HOST)
910 			return;
911 		printf(" ICMP Host Redirect to %pI4 ",
912 			&icmph->un.gateway);
913 		break;
914 	default:
915 #if defined(CONFIG_CMD_PING)
916 		ping_receive(et, ip, len);
917 #endif
918 #ifdef CONFIG_CMD_TFTPPUT
919 		if (packet_icmp_handler)
920 			packet_icmp_handler(icmph->type, icmph->code,
921 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
922 				icmph->un.data, ntohs(ip->udp_len));
923 #endif
924 		break;
925 	}
926 }
927 
928 void
929 NetReceive(uchar *inpkt, int len)
930 {
931 	struct ethernet_hdr *et;
932 	struct ip_udp_hdr *ip;
933 	IPaddr_t dst_ip;
934 	IPaddr_t src_ip;
935 	int eth_proto;
936 #if defined(CONFIG_CMD_CDP)
937 	int iscdp;
938 #endif
939 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
940 
941 	debug_cond(DEBUG_NET_PKT, "packet received\n");
942 
943 	NetRxPacket = inpkt;
944 	NetRxPacketLen = len;
945 	et = (struct ethernet_hdr *)inpkt;
946 
947 	/* too small packet? */
948 	if (len < ETHER_HDR_SIZE)
949 		return;
950 
951 #ifdef CONFIG_API
952 	if (push_packet) {
953 		(*push_packet)(inpkt, len);
954 		return;
955 	}
956 #endif
957 
958 #if defined(CONFIG_CMD_CDP)
959 	/* keep track if packet is CDP */
960 	iscdp = is_cdp_packet(et->et_dest);
961 #endif
962 
963 	myvlanid = ntohs(NetOurVLAN);
964 	if (myvlanid == (ushort)-1)
965 		myvlanid = VLAN_NONE;
966 	mynvlanid = ntohs(NetOurNativeVLAN);
967 	if (mynvlanid == (ushort)-1)
968 		mynvlanid = VLAN_NONE;
969 
970 	eth_proto = ntohs(et->et_protlen);
971 
972 	if (eth_proto < 1514) {
973 		struct e802_hdr *et802 = (struct e802_hdr *)et;
974 		/*
975 		 *	Got a 802.2 packet.  Check the other protocol field.
976 		 *	XXX VLAN over 802.2+SNAP not implemented!
977 		 */
978 		eth_proto = ntohs(et802->et_prot);
979 
980 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
981 		len -= E802_HDR_SIZE;
982 
983 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
984 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
985 		len -= ETHER_HDR_SIZE;
986 
987 	} else {			/* VLAN packet */
988 		struct vlan_ethernet_hdr *vet =
989 			(struct vlan_ethernet_hdr *)et;
990 
991 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
992 
993 		/* too small packet? */
994 		if (len < VLAN_ETHER_HDR_SIZE)
995 			return;
996 
997 		/* if no VLAN active */
998 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
999 #if defined(CONFIG_CMD_CDP)
1000 				&& iscdp == 0
1001 #endif
1002 				)
1003 			return;
1004 
1005 		cti = ntohs(vet->vet_tag);
1006 		vlanid = cti & VLAN_IDMASK;
1007 		eth_proto = ntohs(vet->vet_type);
1008 
1009 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1010 		len -= VLAN_ETHER_HDR_SIZE;
1011 	}
1012 
1013 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1014 
1015 #if defined(CONFIG_CMD_CDP)
1016 	if (iscdp) {
1017 		cdp_receive((uchar *)ip, len);
1018 		return;
1019 	}
1020 #endif
1021 
1022 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1023 		if (vlanid == VLAN_NONE)
1024 			vlanid = (mynvlanid & VLAN_IDMASK);
1025 		/* not matched? */
1026 		if (vlanid != (myvlanid & VLAN_IDMASK))
1027 			return;
1028 	}
1029 
1030 	switch (eth_proto) {
1031 
1032 	case PROT_ARP:
1033 		ArpReceive(et, ip, len);
1034 		break;
1035 
1036 #ifdef CONFIG_CMD_RARP
1037 	case PROT_RARP:
1038 		rarp_receive(ip, len);
1039 		break;
1040 #endif
1041 	case PROT_IP:
1042 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1043 		/* Before we start poking the header, make sure it is there */
1044 		if (len < IP_UDP_HDR_SIZE) {
1045 			debug("len bad %d < %lu\n", len,
1046 				(ulong)IP_UDP_HDR_SIZE);
1047 			return;
1048 		}
1049 		/* Check the packet length */
1050 		if (len < ntohs(ip->ip_len)) {
1051 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1052 			return;
1053 		}
1054 		len = ntohs(ip->ip_len);
1055 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1056 			len, ip->ip_hl_v & 0xff);
1057 
1058 		/* Can't deal with anything except IPv4 */
1059 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1060 			return;
1061 		/* Can't deal with IP options (headers != 20 bytes) */
1062 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1063 			return;
1064 		/* Check the Checksum of the header */
1065 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1066 			debug("checksum bad\n");
1067 			return;
1068 		}
1069 		/* If it is not for us, ignore it */
1070 		dst_ip = NetReadIP(&ip->ip_dst);
1071 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1072 #ifdef CONFIG_MCAST_TFTP
1073 			if (Mcast_addr != dst_ip)
1074 #endif
1075 				return;
1076 		}
1077 		/* Read source IP address for later use */
1078 		src_ip = NetReadIP(&ip->ip_src);
1079 		/*
1080 		 * The function returns the unchanged packet if it's not
1081 		 * a fragment, and either the complete packet or NULL if
1082 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1083 		 */
1084 		ip = NetDefragment(ip, &len);
1085 		if (!ip)
1086 			return;
1087 		/*
1088 		 * watch for ICMP host redirects
1089 		 *
1090 		 * There is no real handler code (yet). We just watch
1091 		 * for ICMP host redirect messages. In case anybody
1092 		 * sees these messages: please contact me
1093 		 * (wd@denx.de), or - even better - send me the
1094 		 * necessary fixes :-)
1095 		 *
1096 		 * Note: in all cases where I have seen this so far
1097 		 * it was a problem with the router configuration,
1098 		 * for instance when a router was configured in the
1099 		 * BOOTP reply, but the TFTP server was on the same
1100 		 * subnet. So this is probably a warning that your
1101 		 * configuration might be wrong. But I'm not really
1102 		 * sure if there aren't any other situations.
1103 		 *
1104 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1105 		 * we send a tftp packet to a dead connection, or when
1106 		 * there is no server at the other end.
1107 		 */
1108 		if (ip->ip_p == IPPROTO_ICMP) {
1109 			receive_icmp(ip, len, src_ip, et);
1110 			return;
1111 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1112 			return;
1113 		}
1114 
1115 		debug_cond(DEBUG_DEV_PKT,
1116 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1117 			&dst_ip, &src_ip, len);
1118 
1119 #ifdef CONFIG_UDP_CHECKSUM
1120 		if (ip->udp_xsum != 0) {
1121 			ulong   xsum;
1122 			ushort *sumptr;
1123 			ushort  sumlen;
1124 
1125 			xsum  = ip->ip_p;
1126 			xsum += (ntohs(ip->udp_len));
1127 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1128 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1129 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1130 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1131 
1132 			sumlen = ntohs(ip->udp_len);
1133 			sumptr = (ushort *) &(ip->udp_src);
1134 
1135 			while (sumlen > 1) {
1136 				ushort sumdata;
1137 
1138 				sumdata = *sumptr++;
1139 				xsum += ntohs(sumdata);
1140 				sumlen -= 2;
1141 			}
1142 			if (sumlen > 0) {
1143 				ushort sumdata;
1144 
1145 				sumdata = *(unsigned char *) sumptr;
1146 				sumdata = (sumdata << 8) & 0xff00;
1147 				xsum += sumdata;
1148 			}
1149 			while ((xsum >> 16) != 0) {
1150 				xsum = (xsum & 0x0000ffff) +
1151 				       ((xsum >> 16) & 0x0000ffff);
1152 			}
1153 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1154 				printf(" UDP wrong checksum %08lx %08x\n",
1155 					xsum, ntohs(ip->udp_xsum));
1156 				return;
1157 			}
1158 		}
1159 #endif
1160 
1161 
1162 #ifdef CONFIG_NETCONSOLE
1163 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1164 					src_ip,
1165 					ntohs(ip->udp_dst),
1166 					ntohs(ip->udp_src),
1167 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1168 #endif
1169 		/*
1170 		 *	IP header OK.  Pass the packet to the current handler.
1171 		 */
1172 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1173 				ntohs(ip->udp_dst),
1174 				src_ip,
1175 				ntohs(ip->udp_src),
1176 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1177 		break;
1178 	}
1179 }
1180 
1181 
1182 /**********************************************************************/
1183 
1184 static int net_check_prereq(enum proto_t protocol)
1185 {
1186 	switch (protocol) {
1187 		/* Fall through */
1188 #if defined(CONFIG_CMD_PING)
1189 	case PING:
1190 		if (NetPingIP == 0) {
1191 			puts("*** ERROR: ping address not given\n");
1192 			return 1;
1193 		}
1194 		goto common;
1195 #endif
1196 #if defined(CONFIG_CMD_SNTP)
1197 	case SNTP:
1198 		if (NetNtpServerIP == 0) {
1199 			puts("*** ERROR: NTP server address not given\n");
1200 			return 1;
1201 		}
1202 		goto common;
1203 #endif
1204 #if defined(CONFIG_CMD_DNS)
1205 	case DNS:
1206 		if (NetOurDNSIP == 0) {
1207 			puts("*** ERROR: DNS server address not given\n");
1208 			return 1;
1209 		}
1210 		goto common;
1211 #endif
1212 #if defined(CONFIG_CMD_NFS)
1213 	case NFS:
1214 #endif
1215 	case TFTPGET:
1216 	case TFTPPUT:
1217 		if (NetServerIP == 0) {
1218 			puts("*** ERROR: `serverip' not set\n");
1219 			return 1;
1220 		}
1221 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1222 	defined(CONFIG_CMD_DNS)
1223 common:
1224 #endif
1225 		/* Fall through */
1226 
1227 	case NETCONS:
1228 	case TFTPSRV:
1229 		if (NetOurIP == 0) {
1230 			puts("*** ERROR: `ipaddr' not set\n");
1231 			return 1;
1232 		}
1233 		/* Fall through */
1234 
1235 #ifdef CONFIG_CMD_RARP
1236 	case RARP:
1237 #endif
1238 	case BOOTP:
1239 	case CDP:
1240 	case DHCP:
1241 	case LINKLOCAL:
1242 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1243 			int num = eth_get_dev_index();
1244 
1245 			switch (num) {
1246 			case -1:
1247 				puts("*** ERROR: No ethernet found.\n");
1248 				return 1;
1249 			case 0:
1250 				puts("*** ERROR: `ethaddr' not set\n");
1251 				break;
1252 			default:
1253 				printf("*** ERROR: `eth%daddr' not set\n",
1254 					num);
1255 				break;
1256 			}
1257 
1258 			NetStartAgain();
1259 			return 2;
1260 		}
1261 		/* Fall through */
1262 	default:
1263 		return 0;
1264 	}
1265 	return 0;		/* OK */
1266 }
1267 /**********************************************************************/
1268 
1269 int
1270 NetCksumOk(uchar *ptr, int len)
1271 {
1272 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1273 }
1274 
1275 
1276 unsigned
1277 NetCksum(uchar *ptr, int len)
1278 {
1279 	ulong	xsum;
1280 	ushort *p = (ushort *)ptr;
1281 
1282 	xsum = 0;
1283 	while (len-- > 0)
1284 		xsum += *p++;
1285 	xsum = (xsum & 0xffff) + (xsum >> 16);
1286 	xsum = (xsum & 0xffff) + (xsum >> 16);
1287 	return xsum & 0xffff;
1288 }
1289 
1290 int
1291 NetEthHdrSize(void)
1292 {
1293 	ushort myvlanid;
1294 
1295 	myvlanid = ntohs(NetOurVLAN);
1296 	if (myvlanid == (ushort)-1)
1297 		myvlanid = VLAN_NONE;
1298 
1299 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1300 		VLAN_ETHER_HDR_SIZE;
1301 }
1302 
1303 int
1304 NetSetEther(uchar *xet, uchar * addr, uint prot)
1305 {
1306 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1307 	ushort myvlanid;
1308 
1309 	myvlanid = ntohs(NetOurVLAN);
1310 	if (myvlanid == (ushort)-1)
1311 		myvlanid = VLAN_NONE;
1312 
1313 	memcpy(et->et_dest, addr, 6);
1314 	memcpy(et->et_src, NetOurEther, 6);
1315 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1316 		et->et_protlen = htons(prot);
1317 		return ETHER_HDR_SIZE;
1318 	} else {
1319 		struct vlan_ethernet_hdr *vet =
1320 			(struct vlan_ethernet_hdr *)xet;
1321 
1322 		vet->vet_vlan_type = htons(PROT_VLAN);
1323 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1324 		vet->vet_type = htons(prot);
1325 		return VLAN_ETHER_HDR_SIZE;
1326 	}
1327 }
1328 
1329 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1330 {
1331 	ushort protlen;
1332 
1333 	memcpy(et->et_dest, addr, 6);
1334 	memcpy(et->et_src, NetOurEther, 6);
1335 	protlen = ntohs(et->et_protlen);
1336 	if (protlen == PROT_VLAN) {
1337 		struct vlan_ethernet_hdr *vet =
1338 			(struct vlan_ethernet_hdr *)et;
1339 		vet->vet_type = htons(prot);
1340 		return VLAN_ETHER_HDR_SIZE;
1341 	} else if (protlen > 1514) {
1342 		et->et_protlen = htons(prot);
1343 		return ETHER_HDR_SIZE;
1344 	} else {
1345 		/* 802.2 + SNAP */
1346 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1347 		et802->et_prot = htons(prot);
1348 		return E802_HDR_SIZE;
1349 	}
1350 }
1351 
1352 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1353 {
1354 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1355 
1356 	/*
1357 	 *	Construct an IP header.
1358 	 */
1359 	/* IP_HDR_SIZE / 4 (not including UDP) */
1360 	ip->ip_hl_v  = 0x45;
1361 	ip->ip_tos   = 0;
1362 	ip->ip_len   = htons(IP_HDR_SIZE);
1363 	ip->ip_id    = htons(NetIPID++);
1364 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1365 	ip->ip_ttl   = 255;
1366 	ip->ip_sum   = 0;
1367 	/* already in network byte order */
1368 	NetCopyIP((void *)&ip->ip_src, &source);
1369 	/* already in network byte order */
1370 	NetCopyIP((void *)&ip->ip_dst, &dest);
1371 }
1372 
1373 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1374 			int len)
1375 {
1376 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1377 
1378 	/*
1379 	 *	If the data is an odd number of bytes, zero the
1380 	 *	byte after the last byte so that the checksum
1381 	 *	will work.
1382 	 */
1383 	if (len & 1)
1384 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1385 
1386 	net_set_ip_header(pkt, dest, NetOurIP);
1387 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1388 	ip->ip_p     = IPPROTO_UDP;
1389 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1390 
1391 	ip->udp_src  = htons(sport);
1392 	ip->udp_dst  = htons(dport);
1393 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1394 	ip->udp_xsum = 0;
1395 }
1396 
1397 void copy_filename(char *dst, const char *src, int size)
1398 {
1399 	if (*src && (*src == '"')) {
1400 		++src;
1401 		--size;
1402 	}
1403 
1404 	while ((--size > 0) && *src && (*src != '"'))
1405 		*dst++ = *src++;
1406 	*dst = '\0';
1407 }
1408 
1409 #if	defined(CONFIG_CMD_NFS)		|| \
1410 	defined(CONFIG_CMD_SNTP)	|| \
1411 	defined(CONFIG_CMD_DNS)
1412 /*
1413  * make port a little random (1024-17407)
1414  * This keeps the math somewhat trivial to compute, and seems to work with
1415  * all supported protocols/clients/servers
1416  */
1417 unsigned int random_port(void)
1418 {
1419 	return 1024 + (get_timer(0) % 0x4000);
1420 }
1421 #endif
1422 
1423 void ip_to_string(IPaddr_t x, char *s)
1424 {
1425 	x = ntohl(x);
1426 	sprintf(s, "%d.%d.%d.%d",
1427 		(int) ((x >> 24) & 0xff),
1428 		(int) ((x >> 16) & 0xff),
1429 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1430 	);
1431 }
1432 
1433 void VLAN_to_string(ushort x, char *s)
1434 {
1435 	x = ntohs(x);
1436 
1437 	if (x == (ushort)-1)
1438 		x = VLAN_NONE;
1439 
1440 	if (x == VLAN_NONE)
1441 		strcpy(s, "none");
1442 	else
1443 		sprintf(s, "%d", x & VLAN_IDMASK);
1444 }
1445 
1446 ushort string_to_VLAN(const char *s)
1447 {
1448 	ushort id;
1449 
1450 	if (s == NULL)
1451 		return htons(VLAN_NONE);
1452 
1453 	if (*s < '0' || *s > '9')
1454 		id = VLAN_NONE;
1455 	else
1456 		id = (ushort)simple_strtoul(s, NULL, 10);
1457 
1458 	return htons(id);
1459 }
1460 
1461 ushort getenv_VLAN(char *var)
1462 {
1463 	return string_to_VLAN(getenv(var));
1464 }
1465