xref: /rk3399_rockchip-uboot/net/net.c (revision be11235ab802844e12d84921a38fd8ae4ddda080)
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 static 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 #if defined(CONFIG_CMD_NFS)
218 	const char *s = getenv("autoload");
219 
220 	if (s != NULL && strcmp(s, "NFS") == 0) {
221 		/*
222 		 * Use NFS to load the bootfile.
223 		 */
224 		NfsStart();
225 		return;
226 	}
227 #endif
228 	if (getenv_yesno("autoload") == 0) {
229 		/*
230 		 * Just use BOOTP/RARP to configure system;
231 		 * Do not use TFTP to load the bootfile.
232 		 */
233 		net_set_state(NETLOOP_SUCCESS);
234 		return;
235 	}
236 	TftpStart(TFTPGET);
237 }
238 
239 static void NetInitLoop(void)
240 {
241 	static int env_changed_id;
242 	int env_id = get_env_id();
243 
244 	/* update only when the environment has changed */
245 	if (env_changed_id != env_id) {
246 		NetOurIP = getenv_IPaddr("ipaddr");
247 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
248 		NetOurSubnetMask = getenv_IPaddr("netmask");
249 		NetServerIP = getenv_IPaddr("serverip");
250 		NetOurNativeVLAN = getenv_VLAN("nvlan");
251 		NetOurVLAN = getenv_VLAN("vlan");
252 #if defined(CONFIG_CMD_DNS)
253 		NetOurDNSIP = getenv_IPaddr("dnsip");
254 #endif
255 		env_changed_id = env_id;
256 	}
257 	memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
258 
259 	return;
260 }
261 
262 static void net_clear_handlers(void)
263 {
264 	net_set_udp_handler(NULL);
265 	net_set_arp_handler(NULL);
266 	NetSetTimeout(0, NULL);
267 }
268 
269 static void net_cleanup_loop(void)
270 {
271 	net_clear_handlers();
272 }
273 
274 void net_init(void)
275 {
276 	static int first_call = 1;
277 
278 	if (first_call) {
279 		/*
280 		 *	Setup packet buffers, aligned correctly.
281 		 */
282 		int i;
283 
284 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
285 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
286 		for (i = 0; i < PKTBUFSRX; i++)
287 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
288 
289 		ArpInit();
290 		net_clear_handlers();
291 
292 		/* Only need to setup buffer pointers once. */
293 		first_call = 0;
294 	}
295 
296 	NetInitLoop();
297 }
298 
299 /**********************************************************************/
300 /*
301  *	Main network processing loop.
302  */
303 
304 int NetLoop(enum proto_t protocol)
305 {
306 	bd_t *bd = gd->bd;
307 	int ret = -1;
308 
309 	NetRestarted = 0;
310 	NetDevExists = 0;
311 	NetTryCount = 1;
312 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
313 
314 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
315 	net_init();
316 	if (eth_is_on_demand_init() || protocol != NETCONS) {
317 		eth_halt();
318 		eth_set_current();
319 		if (eth_init(bd) < 0) {
320 			eth_halt();
321 			return -1;
322 		}
323 	} else
324 		eth_init_state_only(bd);
325 
326 restart:
327 	net_set_state(NETLOOP_CONTINUE);
328 
329 	/*
330 	 *	Start the ball rolling with the given start function.  From
331 	 *	here on, this code is a state machine driven by received
332 	 *	packets and timer events.
333 	 */
334 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
335 	NetInitLoop();
336 
337 	switch (net_check_prereq(protocol)) {
338 	case 1:
339 		/* network not configured */
340 		eth_halt();
341 		return -1;
342 
343 	case 2:
344 		/* network device not configured */
345 		break;
346 
347 	case 0:
348 		NetDevExists = 1;
349 		NetBootFileXferSize = 0;
350 		switch (protocol) {
351 		case TFTPGET:
352 #ifdef CONFIG_CMD_TFTPPUT
353 		case TFTPPUT:
354 #endif
355 			/* always use ARP to get server ethernet address */
356 			TftpStart(protocol);
357 			break;
358 #ifdef CONFIG_CMD_TFTPSRV
359 		case TFTPSRV:
360 			TftpStartServer();
361 			break;
362 #endif
363 #if defined(CONFIG_CMD_DHCP)
364 		case DHCP:
365 			BootpTry = 0;
366 			NetOurIP = 0;
367 			DhcpRequest();		/* Basically same as BOOTP */
368 			break;
369 #endif
370 
371 		case BOOTP:
372 			BootpTry = 0;
373 			NetOurIP = 0;
374 			BootpRequest();
375 			break;
376 
377 #if defined(CONFIG_CMD_RARP)
378 		case RARP:
379 			RarpTry = 0;
380 			NetOurIP = 0;
381 			RarpRequest();
382 			break;
383 #endif
384 #if defined(CONFIG_CMD_PING)
385 		case PING:
386 			ping_start();
387 			break;
388 #endif
389 #if defined(CONFIG_CMD_NFS)
390 		case NFS:
391 			NfsStart();
392 			break;
393 #endif
394 #if defined(CONFIG_CMD_CDP)
395 		case CDP:
396 			CDPStart();
397 			break;
398 #endif
399 #ifdef CONFIG_NETCONSOLE
400 		case NETCONS:
401 			NcStart();
402 			break;
403 #endif
404 #if defined(CONFIG_CMD_SNTP)
405 		case SNTP:
406 			SntpStart();
407 			break;
408 #endif
409 #if defined(CONFIG_CMD_DNS)
410 		case DNS:
411 			DnsStart();
412 			break;
413 #endif
414 #if defined(CONFIG_CMD_LINK_LOCAL)
415 		case LINKLOCAL:
416 			link_local_start();
417 			break;
418 #endif
419 		default:
420 			break;
421 		}
422 
423 		break;
424 	}
425 
426 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
427 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
428 	defined(CONFIG_STATUS_LED)			&& \
429 	defined(STATUS_LED_RED)
430 	/*
431 	 * Echo the inverted link state to the fault LED.
432 	 */
433 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
434 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
435 	else
436 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
437 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
438 #endif /* CONFIG_MII, ... */
439 
440 	/*
441 	 *	Main packet reception loop.  Loop receiving packets until
442 	 *	someone sets `net_state' to a state that terminates.
443 	 */
444 	for (;;) {
445 		WATCHDOG_RESET();
446 #ifdef CONFIG_SHOW_ACTIVITY
447 		show_activity(1);
448 #endif
449 		/*
450 		 *	Check the ethernet for a new packet.  The ethernet
451 		 *	receive routine will process it.
452 		 */
453 		eth_rx();
454 
455 		/*
456 		 *	Abort if ctrl-c was pressed.
457 		 */
458 		if (ctrlc()) {
459 			/* cancel any ARP that may not have completed */
460 			NetArpWaitPacketIP = 0;
461 
462 			net_cleanup_loop();
463 			eth_halt();
464 			/* Invalidate the last protocol */
465 			eth_set_last_protocol(BOOTP);
466 
467 			puts("\nAbort\n");
468 			/* include a debug print as well incase the debug
469 			   messages are directed to stderr */
470 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
471 			goto done;
472 		}
473 
474 		ArpTimeoutCheck();
475 
476 		/*
477 		 *	Check for a timeout, and run the timeout handler
478 		 *	if we have one.
479 		 */
480 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
481 			thand_f *x;
482 
483 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
484 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
485 	defined(CONFIG_STATUS_LED)			&& \
486 	defined(STATUS_LED_RED)
487 			/*
488 			 * Echo the inverted link state to the fault LED.
489 			 */
490 			if (miiphy_link(eth_get_dev()->name,
491 				       CONFIG_SYS_FAULT_MII_ADDR)) {
492 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
493 			} else {
494 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
495 			}
496 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
497 #endif /* CONFIG_MII, ... */
498 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
499 			x = timeHandler;
500 			timeHandler = (thand_f *)0;
501 			(*x)();
502 		}
503 
504 
505 		switch (net_state) {
506 
507 		case NETLOOP_RESTART:
508 			NetRestarted = 1;
509 			goto restart;
510 
511 		case NETLOOP_SUCCESS:
512 			net_cleanup_loop();
513 			if (NetBootFileXferSize > 0) {
514 				char buf[20];
515 				printf("Bytes transferred = %ld (%lx hex)\n",
516 					NetBootFileXferSize,
517 					NetBootFileXferSize);
518 				sprintf(buf, "%lX", NetBootFileXferSize);
519 				setenv("filesize", buf);
520 
521 				sprintf(buf, "%lX", (unsigned long)load_addr);
522 				setenv("fileaddr", buf);
523 			}
524 			if (protocol != NETCONS)
525 				eth_halt();
526 			else
527 				eth_halt_state_only();
528 
529 			eth_set_last_protocol(protocol);
530 
531 			ret = NetBootFileXferSize;
532 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
533 			goto done;
534 
535 		case NETLOOP_FAIL:
536 			net_cleanup_loop();
537 			/* Invalidate the last protocol */
538 			eth_set_last_protocol(BOOTP);
539 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
540 			goto done;
541 
542 		case NETLOOP_CONTINUE:
543 			continue;
544 		}
545 	}
546 
547 done:
548 #ifdef CONFIG_CMD_TFTPPUT
549 	/* Clear out the handlers */
550 	net_set_udp_handler(NULL);
551 	net_set_icmp_handler(NULL);
552 #endif
553 	return ret;
554 }
555 
556 /**********************************************************************/
557 
558 static void
559 startAgainTimeout(void)
560 {
561 	net_set_state(NETLOOP_RESTART);
562 }
563 
564 void NetStartAgain(void)
565 {
566 	char *nretry;
567 	int retry_forever = 0;
568 	unsigned long retrycnt = 0;
569 
570 	nretry = getenv("netretry");
571 	if (nretry) {
572 		if (!strcmp(nretry, "yes"))
573 			retry_forever = 1;
574 		else if (!strcmp(nretry, "no"))
575 			retrycnt = 0;
576 		else if (!strcmp(nretry, "once"))
577 			retrycnt = 1;
578 		else
579 			retrycnt = simple_strtoul(nretry, NULL, 0);
580 	} else
581 		retry_forever = 1;
582 
583 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
584 		eth_halt();
585 		net_set_state(NETLOOP_FAIL);
586 		return;
587 	}
588 
589 	NetTryCount++;
590 
591 	eth_halt();
592 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
593 	eth_try_another(!NetRestarted);
594 #endif
595 	eth_init(gd->bd);
596 	if (NetRestartWrap) {
597 		NetRestartWrap = 0;
598 		if (NetDevExists) {
599 			NetSetTimeout(10000UL, startAgainTimeout);
600 			net_set_udp_handler(NULL);
601 		} else {
602 			net_set_state(NETLOOP_FAIL);
603 		}
604 	} else {
605 		net_set_state(NETLOOP_RESTART);
606 	}
607 }
608 
609 /**********************************************************************/
610 /*
611  *	Miscelaneous bits.
612  */
613 
614 static void dummy_handler(uchar *pkt, unsigned dport,
615 			IPaddr_t sip, unsigned sport,
616 			unsigned len)
617 {
618 }
619 
620 rxhand_f *net_get_udp_handler(void)
621 {
622 	return udp_packet_handler;
623 }
624 
625 void net_set_udp_handler(rxhand_f *f)
626 {
627 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
628 	if (f == NULL)
629 		udp_packet_handler = dummy_handler;
630 	else
631 		udp_packet_handler = f;
632 }
633 
634 rxhand_f *net_get_arp_handler(void)
635 {
636 	return arp_packet_handler;
637 }
638 
639 void net_set_arp_handler(rxhand_f *f)
640 {
641 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
642 	if (f == NULL)
643 		arp_packet_handler = dummy_handler;
644 	else
645 		arp_packet_handler = f;
646 }
647 
648 #ifdef CONFIG_CMD_TFTPPUT
649 void net_set_icmp_handler(rxhand_icmp_f *f)
650 {
651 	packet_icmp_handler = f;
652 }
653 #endif
654 
655 void
656 NetSetTimeout(ulong iv, thand_f *f)
657 {
658 	if (iv == 0) {
659 		debug_cond(DEBUG_INT_STATE,
660 			"--- NetLoop timeout handler cancelled\n");
661 		timeHandler = (thand_f *)0;
662 	} else {
663 		debug_cond(DEBUG_INT_STATE,
664 			"--- NetLoop timeout handler set (%p)\n", f);
665 		timeHandler = f;
666 		timeStart = get_timer(0);
667 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
668 	}
669 }
670 
671 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
672 		int payload_len)
673 {
674 	uchar *pkt;
675 	int eth_hdr_size;
676 	int pkt_hdr_size;
677 
678 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
679 	assert(NetTxPacket != NULL);
680 	if (NetTxPacket == NULL)
681 		return -1;
682 
683 	/* convert to new style broadcast */
684 	if (dest == 0)
685 		dest = 0xFFFFFFFF;
686 
687 	/* if broadcast, make the ether address a broadcast and don't do ARP */
688 	if (dest == 0xFFFFFFFF)
689 		ether = NetBcastAddr;
690 
691 	pkt = (uchar *)NetTxPacket;
692 
693 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
694 	pkt += eth_hdr_size;
695 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
696 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
697 
698 	/* if MAC address was not discovered yet, do an ARP request */
699 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
700 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
701 
702 		/* save the ip and eth addr for the packet to send after arp */
703 		NetArpWaitPacketIP = dest;
704 		NetArpWaitPacketMAC = ether;
705 
706 		/* size of the waiting packet */
707 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
708 
709 		/* and do the ARP request */
710 		NetArpWaitTry = 1;
711 		NetArpWaitTimerStart = get_timer(0);
712 		ArpRequest();
713 		return 1;	/* waiting */
714 	} else {
715 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
716 			&dest, ether);
717 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
718 		return 0;	/* transmitted */
719 	}
720 }
721 
722 #ifdef CONFIG_IP_DEFRAG
723 /*
724  * This function collects fragments in a single packet, according
725  * to the algorithm in RFC815. It returns NULL or the pointer to
726  * a complete packet, in static storage
727  */
728 #ifndef CONFIG_NET_MAXDEFRAG
729 #define CONFIG_NET_MAXDEFRAG 16384
730 #endif
731 /*
732  * MAXDEFRAG, above, is chosen in the config file and  is real data
733  * so we need to add the NFS overhead, which is more than TFTP.
734  * To use sizeof in the internal unnamed structures, we need a real
735  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
736  * The compiler doesn't complain nor allocates the actual structure
737  */
738 static struct rpc_t rpc_specimen;
739 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
740 
741 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
742 
743 /*
744  * this is the packet being assembled, either data or frag control.
745  * Fragments go by 8 bytes, so this union must be 8 bytes long
746  */
747 struct hole {
748 	/* first_byte is address of this structure */
749 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
750 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
751 	u16 prev_hole;	/* index of prev, 0 == none */
752 	u16 unused;
753 };
754 
755 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
756 {
757 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
758 	static u16 first_hole, total_len;
759 	struct hole *payload, *thisfrag, *h, *newh;
760 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
761 	uchar *indata = (uchar *)ip;
762 	int offset8, start, len, done = 0;
763 	u16 ip_off = ntohs(ip->ip_off);
764 
765 	/* payload starts after IP header, this fragment is in there */
766 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
767 	offset8 =  (ip_off & IP_OFFS);
768 	thisfrag = payload + offset8;
769 	start = offset8 * 8;
770 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
771 
772 	if (start + len > IP_MAXUDP) /* fragment extends too far */
773 		return NULL;
774 
775 	if (!total_len || localip->ip_id != ip->ip_id) {
776 		/* new (or different) packet, reset structs */
777 		total_len = 0xffff;
778 		payload[0].last_byte = ~0;
779 		payload[0].next_hole = 0;
780 		payload[0].prev_hole = 0;
781 		first_hole = 0;
782 		/* any IP header will work, copy the first we received */
783 		memcpy(localip, ip, IP_HDR_SIZE);
784 	}
785 
786 	/*
787 	 * What follows is the reassembly algorithm. We use the payload
788 	 * array as a linked list of hole descriptors, as each hole starts
789 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
790 	 * so it is represented as byte count, not as 8-byte blocks.
791 	 */
792 
793 	h = payload + first_hole;
794 	while (h->last_byte < start) {
795 		if (!h->next_hole) {
796 			/* no hole that far away */
797 			return NULL;
798 		}
799 		h = payload + h->next_hole;
800 	}
801 
802 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
803 	if (offset8 + ((len + 7) / 8) <= h - payload) {
804 		/* no overlap with holes (dup fragment?) */
805 		return NULL;
806 	}
807 
808 	if (!(ip_off & IP_FLAGS_MFRAG)) {
809 		/* no more fragmentss: truncate this (last) hole */
810 		total_len = start + len;
811 		h->last_byte = start + len;
812 	}
813 
814 	/*
815 	 * There is some overlap: fix the hole list. This code doesn't
816 	 * deal with a fragment that overlaps with two different holes
817 	 * (thus being a superset of a previously-received fragment).
818 	 */
819 
820 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
821 		/* complete overlap with hole: remove hole */
822 		if (!h->prev_hole && !h->next_hole) {
823 			/* last remaining hole */
824 			done = 1;
825 		} else if (!h->prev_hole) {
826 			/* first hole */
827 			first_hole = h->next_hole;
828 			payload[h->next_hole].prev_hole = 0;
829 		} else if (!h->next_hole) {
830 			/* last hole */
831 			payload[h->prev_hole].next_hole = 0;
832 		} else {
833 			/* in the middle of the list */
834 			payload[h->next_hole].prev_hole = h->prev_hole;
835 			payload[h->prev_hole].next_hole = h->next_hole;
836 		}
837 
838 	} else if (h->last_byte <= start + len) {
839 		/* overlaps with final part of the hole: shorten this hole */
840 		h->last_byte = start;
841 
842 	} else if (h >= thisfrag) {
843 		/* overlaps with initial part of the hole: move this hole */
844 		newh = thisfrag + (len / 8);
845 		*newh = *h;
846 		h = newh;
847 		if (h->next_hole)
848 			payload[h->next_hole].prev_hole = (h - payload);
849 		if (h->prev_hole)
850 			payload[h->prev_hole].next_hole = (h - payload);
851 		else
852 			first_hole = (h - payload);
853 
854 	} else {
855 		/* fragment sits in the middle: split the hole */
856 		newh = thisfrag + (len / 8);
857 		*newh = *h;
858 		h->last_byte = start;
859 		h->next_hole = (newh - payload);
860 		newh->prev_hole = (h - payload);
861 		if (newh->next_hole)
862 			payload[newh->next_hole].prev_hole = (newh - payload);
863 	}
864 
865 	/* finally copy this fragment and possibly return whole packet */
866 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
867 	if (!done)
868 		return NULL;
869 
870 	localip->ip_len = htons(total_len);
871 	*lenp = total_len + IP_HDR_SIZE;
872 	return localip;
873 }
874 
875 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
876 {
877 	u16 ip_off = ntohs(ip->ip_off);
878 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
879 		return ip; /* not a fragment */
880 	return __NetDefragment(ip, lenp);
881 }
882 
883 #else /* !CONFIG_IP_DEFRAG */
884 
885 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
886 {
887 	u16 ip_off = ntohs(ip->ip_off);
888 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
889 		return ip; /* not a fragment */
890 	return NULL;
891 }
892 #endif
893 
894 /**
895  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
896  * drop others.
897  *
898  * @parma ip	IP packet containing the ICMP
899  */
900 static void receive_icmp(struct ip_udp_hdr *ip, int len,
901 			IPaddr_t src_ip, struct ethernet_hdr *et)
902 {
903 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
904 
905 	switch (icmph->type) {
906 	case ICMP_REDIRECT:
907 		if (icmph->code != ICMP_REDIR_HOST)
908 			return;
909 		printf(" ICMP Host Redirect to %pI4 ",
910 			&icmph->un.gateway);
911 		break;
912 	default:
913 #if defined(CONFIG_CMD_PING)
914 		ping_receive(et, ip, len);
915 #endif
916 #ifdef CONFIG_CMD_TFTPPUT
917 		if (packet_icmp_handler)
918 			packet_icmp_handler(icmph->type, icmph->code,
919 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
920 				icmph->un.data, ntohs(ip->udp_len));
921 #endif
922 		break;
923 	}
924 }
925 
926 void
927 NetReceive(uchar *inpkt, int len)
928 {
929 	struct ethernet_hdr *et;
930 	struct ip_udp_hdr *ip;
931 	IPaddr_t dst_ip;
932 	IPaddr_t src_ip;
933 	int eth_proto;
934 #if defined(CONFIG_CMD_CDP)
935 	int iscdp;
936 #endif
937 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
938 
939 	debug_cond(DEBUG_NET_PKT, "packet received\n");
940 
941 	NetRxPacket = inpkt;
942 	NetRxPacketLen = len;
943 	et = (struct ethernet_hdr *)inpkt;
944 
945 	/* too small packet? */
946 	if (len < ETHER_HDR_SIZE)
947 		return;
948 
949 #ifdef CONFIG_API
950 	if (push_packet) {
951 		(*push_packet)(inpkt, len);
952 		return;
953 	}
954 #endif
955 
956 #if defined(CONFIG_CMD_CDP)
957 	/* keep track if packet is CDP */
958 	iscdp = is_cdp_packet(et->et_dest);
959 #endif
960 
961 	myvlanid = ntohs(NetOurVLAN);
962 	if (myvlanid == (ushort)-1)
963 		myvlanid = VLAN_NONE;
964 	mynvlanid = ntohs(NetOurNativeVLAN);
965 	if (mynvlanid == (ushort)-1)
966 		mynvlanid = VLAN_NONE;
967 
968 	eth_proto = ntohs(et->et_protlen);
969 
970 	if (eth_proto < 1514) {
971 		struct e802_hdr *et802 = (struct e802_hdr *)et;
972 		/*
973 		 *	Got a 802.2 packet.  Check the other protocol field.
974 		 *	XXX VLAN over 802.2+SNAP not implemented!
975 		 */
976 		eth_proto = ntohs(et802->et_prot);
977 
978 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
979 		len -= E802_HDR_SIZE;
980 
981 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
982 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
983 		len -= ETHER_HDR_SIZE;
984 
985 	} else {			/* VLAN packet */
986 		struct vlan_ethernet_hdr *vet =
987 			(struct vlan_ethernet_hdr *)et;
988 
989 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
990 
991 		/* too small packet? */
992 		if (len < VLAN_ETHER_HDR_SIZE)
993 			return;
994 
995 		/* if no VLAN active */
996 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
997 #if defined(CONFIG_CMD_CDP)
998 				&& iscdp == 0
999 #endif
1000 				)
1001 			return;
1002 
1003 		cti = ntohs(vet->vet_tag);
1004 		vlanid = cti & VLAN_IDMASK;
1005 		eth_proto = ntohs(vet->vet_type);
1006 
1007 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1008 		len -= VLAN_ETHER_HDR_SIZE;
1009 	}
1010 
1011 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1012 
1013 #if defined(CONFIG_CMD_CDP)
1014 	if (iscdp) {
1015 		cdp_receive((uchar *)ip, len);
1016 		return;
1017 	}
1018 #endif
1019 
1020 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1021 		if (vlanid == VLAN_NONE)
1022 			vlanid = (mynvlanid & VLAN_IDMASK);
1023 		/* not matched? */
1024 		if (vlanid != (myvlanid & VLAN_IDMASK))
1025 			return;
1026 	}
1027 
1028 	switch (eth_proto) {
1029 
1030 	case PROT_ARP:
1031 		ArpReceive(et, ip, len);
1032 		break;
1033 
1034 #ifdef CONFIG_CMD_RARP
1035 	case PROT_RARP:
1036 		rarp_receive(ip, len);
1037 		break;
1038 #endif
1039 	case PROT_IP:
1040 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1041 		/* Before we start poking the header, make sure it is there */
1042 		if (len < IP_UDP_HDR_SIZE) {
1043 			debug("len bad %d < %lu\n", len,
1044 				(ulong)IP_UDP_HDR_SIZE);
1045 			return;
1046 		}
1047 		/* Check the packet length */
1048 		if (len < ntohs(ip->ip_len)) {
1049 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1050 			return;
1051 		}
1052 		len = ntohs(ip->ip_len);
1053 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1054 			len, ip->ip_hl_v & 0xff);
1055 
1056 		/* Can't deal with anything except IPv4 */
1057 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1058 			return;
1059 		/* Can't deal with IP options (headers != 20 bytes) */
1060 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1061 			return;
1062 		/* Check the Checksum of the header */
1063 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1064 			debug("checksum bad\n");
1065 			return;
1066 		}
1067 		/* If it is not for us, ignore it */
1068 		dst_ip = NetReadIP(&ip->ip_dst);
1069 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1070 #ifdef CONFIG_MCAST_TFTP
1071 			if (Mcast_addr != dst_ip)
1072 #endif
1073 				return;
1074 		}
1075 		/* Read source IP address for later use */
1076 		src_ip = NetReadIP(&ip->ip_src);
1077 		/*
1078 		 * The function returns the unchanged packet if it's not
1079 		 * a fragment, and either the complete packet or NULL if
1080 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1081 		 */
1082 		ip = NetDefragment(ip, &len);
1083 		if (!ip)
1084 			return;
1085 		/*
1086 		 * watch for ICMP host redirects
1087 		 *
1088 		 * There is no real handler code (yet). We just watch
1089 		 * for ICMP host redirect messages. In case anybody
1090 		 * sees these messages: please contact me
1091 		 * (wd@denx.de), or - even better - send me the
1092 		 * necessary fixes :-)
1093 		 *
1094 		 * Note: in all cases where I have seen this so far
1095 		 * it was a problem with the router configuration,
1096 		 * for instance when a router was configured in the
1097 		 * BOOTP reply, but the TFTP server was on the same
1098 		 * subnet. So this is probably a warning that your
1099 		 * configuration might be wrong. But I'm not really
1100 		 * sure if there aren't any other situations.
1101 		 *
1102 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1103 		 * we send a tftp packet to a dead connection, or when
1104 		 * there is no server at the other end.
1105 		 */
1106 		if (ip->ip_p == IPPROTO_ICMP) {
1107 			receive_icmp(ip, len, src_ip, et);
1108 			return;
1109 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1110 			return;
1111 		}
1112 
1113 		debug_cond(DEBUG_DEV_PKT,
1114 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1115 			&dst_ip, &src_ip, len);
1116 
1117 #ifdef CONFIG_UDP_CHECKSUM
1118 		if (ip->udp_xsum != 0) {
1119 			ulong   xsum;
1120 			ushort *sumptr;
1121 			ushort  sumlen;
1122 
1123 			xsum  = ip->ip_p;
1124 			xsum += (ntohs(ip->udp_len));
1125 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1126 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1127 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1128 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1129 
1130 			sumlen = ntohs(ip->udp_len);
1131 			sumptr = (ushort *) &(ip->udp_src);
1132 
1133 			while (sumlen > 1) {
1134 				ushort sumdata;
1135 
1136 				sumdata = *sumptr++;
1137 				xsum += ntohs(sumdata);
1138 				sumlen -= 2;
1139 			}
1140 			if (sumlen > 0) {
1141 				ushort sumdata;
1142 
1143 				sumdata = *(unsigned char *) sumptr;
1144 				sumdata = (sumdata << 8) & 0xff00;
1145 				xsum += sumdata;
1146 			}
1147 			while ((xsum >> 16) != 0) {
1148 				xsum = (xsum & 0x0000ffff) +
1149 				       ((xsum >> 16) & 0x0000ffff);
1150 			}
1151 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1152 				printf(" UDP wrong checksum %08lx %08x\n",
1153 					xsum, ntohs(ip->udp_xsum));
1154 				return;
1155 			}
1156 		}
1157 #endif
1158 
1159 
1160 #ifdef CONFIG_NETCONSOLE
1161 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1162 					src_ip,
1163 					ntohs(ip->udp_dst),
1164 					ntohs(ip->udp_src),
1165 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1166 #endif
1167 		/*
1168 		 *	IP header OK.  Pass the packet to the current handler.
1169 		 */
1170 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1171 				ntohs(ip->udp_dst),
1172 				src_ip,
1173 				ntohs(ip->udp_src),
1174 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1175 		break;
1176 	}
1177 }
1178 
1179 
1180 /**********************************************************************/
1181 
1182 static int net_check_prereq(enum proto_t protocol)
1183 {
1184 	switch (protocol) {
1185 		/* Fall through */
1186 #if defined(CONFIG_CMD_PING)
1187 	case PING:
1188 		if (NetPingIP == 0) {
1189 			puts("*** ERROR: ping address not given\n");
1190 			return 1;
1191 		}
1192 		goto common;
1193 #endif
1194 #if defined(CONFIG_CMD_SNTP)
1195 	case SNTP:
1196 		if (NetNtpServerIP == 0) {
1197 			puts("*** ERROR: NTP server address not given\n");
1198 			return 1;
1199 		}
1200 		goto common;
1201 #endif
1202 #if defined(CONFIG_CMD_DNS)
1203 	case DNS:
1204 		if (NetOurDNSIP == 0) {
1205 			puts("*** ERROR: DNS server address not given\n");
1206 			return 1;
1207 		}
1208 		goto common;
1209 #endif
1210 #if defined(CONFIG_CMD_NFS)
1211 	case NFS:
1212 #endif
1213 	case TFTPGET:
1214 	case TFTPPUT:
1215 		if (NetServerIP == 0) {
1216 			puts("*** ERROR: `serverip' not set\n");
1217 			return 1;
1218 		}
1219 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1220 	defined(CONFIG_CMD_DNS)
1221 common:
1222 #endif
1223 		/* Fall through */
1224 
1225 	case NETCONS:
1226 	case TFTPSRV:
1227 		if (NetOurIP == 0) {
1228 			puts("*** ERROR: `ipaddr' not set\n");
1229 			return 1;
1230 		}
1231 		/* Fall through */
1232 
1233 #ifdef CONFIG_CMD_RARP
1234 	case RARP:
1235 #endif
1236 	case BOOTP:
1237 	case CDP:
1238 	case DHCP:
1239 	case LINKLOCAL:
1240 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1241 			int num = eth_get_dev_index();
1242 
1243 			switch (num) {
1244 			case -1:
1245 				puts("*** ERROR: No ethernet found.\n");
1246 				return 1;
1247 			case 0:
1248 				puts("*** ERROR: `ethaddr' not set\n");
1249 				break;
1250 			default:
1251 				printf("*** ERROR: `eth%daddr' not set\n",
1252 					num);
1253 				break;
1254 			}
1255 
1256 			NetStartAgain();
1257 			return 2;
1258 		}
1259 		/* Fall through */
1260 	default:
1261 		return 0;
1262 	}
1263 	return 0;		/* OK */
1264 }
1265 /**********************************************************************/
1266 
1267 int
1268 NetCksumOk(uchar *ptr, int len)
1269 {
1270 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1271 }
1272 
1273 
1274 unsigned
1275 NetCksum(uchar *ptr, int len)
1276 {
1277 	ulong	xsum;
1278 	ushort *p = (ushort *)ptr;
1279 
1280 	xsum = 0;
1281 	while (len-- > 0)
1282 		xsum += *p++;
1283 	xsum = (xsum & 0xffff) + (xsum >> 16);
1284 	xsum = (xsum & 0xffff) + (xsum >> 16);
1285 	return xsum & 0xffff;
1286 }
1287 
1288 int
1289 NetEthHdrSize(void)
1290 {
1291 	ushort myvlanid;
1292 
1293 	myvlanid = ntohs(NetOurVLAN);
1294 	if (myvlanid == (ushort)-1)
1295 		myvlanid = VLAN_NONE;
1296 
1297 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1298 		VLAN_ETHER_HDR_SIZE;
1299 }
1300 
1301 int
1302 NetSetEther(uchar *xet, uchar * addr, uint prot)
1303 {
1304 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1305 	ushort myvlanid;
1306 
1307 	myvlanid = ntohs(NetOurVLAN);
1308 	if (myvlanid == (ushort)-1)
1309 		myvlanid = VLAN_NONE;
1310 
1311 	memcpy(et->et_dest, addr, 6);
1312 	memcpy(et->et_src, NetOurEther, 6);
1313 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1314 		et->et_protlen = htons(prot);
1315 		return ETHER_HDR_SIZE;
1316 	} else {
1317 		struct vlan_ethernet_hdr *vet =
1318 			(struct vlan_ethernet_hdr *)xet;
1319 
1320 		vet->vet_vlan_type = htons(PROT_VLAN);
1321 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1322 		vet->vet_type = htons(prot);
1323 		return VLAN_ETHER_HDR_SIZE;
1324 	}
1325 }
1326 
1327 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1328 {
1329 	ushort protlen;
1330 
1331 	memcpy(et->et_dest, addr, 6);
1332 	memcpy(et->et_src, NetOurEther, 6);
1333 	protlen = ntohs(et->et_protlen);
1334 	if (protlen == PROT_VLAN) {
1335 		struct vlan_ethernet_hdr *vet =
1336 			(struct vlan_ethernet_hdr *)et;
1337 		vet->vet_type = htons(prot);
1338 		return VLAN_ETHER_HDR_SIZE;
1339 	} else if (protlen > 1514) {
1340 		et->et_protlen = htons(prot);
1341 		return ETHER_HDR_SIZE;
1342 	} else {
1343 		/* 802.2 + SNAP */
1344 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1345 		et802->et_prot = htons(prot);
1346 		return E802_HDR_SIZE;
1347 	}
1348 }
1349 
1350 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1351 {
1352 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1353 
1354 	/*
1355 	 *	Construct an IP header.
1356 	 */
1357 	/* IP_HDR_SIZE / 4 (not including UDP) */
1358 	ip->ip_hl_v  = 0x45;
1359 	ip->ip_tos   = 0;
1360 	ip->ip_len   = htons(IP_HDR_SIZE);
1361 	ip->ip_id    = htons(NetIPID++);
1362 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1363 	ip->ip_ttl   = 255;
1364 	ip->ip_sum   = 0;
1365 	/* already in network byte order */
1366 	NetCopyIP((void *)&ip->ip_src, &source);
1367 	/* already in network byte order */
1368 	NetCopyIP((void *)&ip->ip_dst, &dest);
1369 }
1370 
1371 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1372 			int len)
1373 {
1374 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1375 
1376 	/*
1377 	 *	If the data is an odd number of bytes, zero the
1378 	 *	byte after the last byte so that the checksum
1379 	 *	will work.
1380 	 */
1381 	if (len & 1)
1382 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1383 
1384 	net_set_ip_header(pkt, dest, NetOurIP);
1385 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1386 	ip->ip_p     = IPPROTO_UDP;
1387 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1388 
1389 	ip->udp_src  = htons(sport);
1390 	ip->udp_dst  = htons(dport);
1391 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1392 	ip->udp_xsum = 0;
1393 }
1394 
1395 void copy_filename(char *dst, const char *src, int size)
1396 {
1397 	if (*src && (*src == '"')) {
1398 		++src;
1399 		--size;
1400 	}
1401 
1402 	while ((--size > 0) && *src && (*src != '"'))
1403 		*dst++ = *src++;
1404 	*dst = '\0';
1405 }
1406 
1407 #if	defined(CONFIG_CMD_NFS)		|| \
1408 	defined(CONFIG_CMD_SNTP)	|| \
1409 	defined(CONFIG_CMD_DNS)
1410 /*
1411  * make port a little random (1024-17407)
1412  * This keeps the math somewhat trivial to compute, and seems to work with
1413  * all supported protocols/clients/servers
1414  */
1415 unsigned int random_port(void)
1416 {
1417 	return 1024 + (get_timer(0) % 0x4000);
1418 }
1419 #endif
1420 
1421 void ip_to_string(IPaddr_t x, char *s)
1422 {
1423 	x = ntohl(x);
1424 	sprintf(s, "%d.%d.%d.%d",
1425 		(int) ((x >> 24) & 0xff),
1426 		(int) ((x >> 16) & 0xff),
1427 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1428 	);
1429 }
1430 
1431 void VLAN_to_string(ushort x, char *s)
1432 {
1433 	x = ntohs(x);
1434 
1435 	if (x == (ushort)-1)
1436 		x = VLAN_NONE;
1437 
1438 	if (x == VLAN_NONE)
1439 		strcpy(s, "none");
1440 	else
1441 		sprintf(s, "%d", x & VLAN_IDMASK);
1442 }
1443 
1444 ushort string_to_VLAN(const char *s)
1445 {
1446 	ushort id;
1447 
1448 	if (s == NULL)
1449 		return htons(VLAN_NONE);
1450 
1451 	if (*s < '0' || *s > '9')
1452 		id = VLAN_NONE;
1453 	else
1454 		id = (ushort)simple_strtoul(s, NULL, 10);
1455 
1456 	return htons(id);
1457 }
1458 
1459 ushort getenv_VLAN(char *var)
1460 {
1461 	return string_to_VLAN(getenv(var));
1462 }
1463