xref: /rk3399_rockchip-uboot/net/net.c (revision 05c3e68f8518809616cd4ec5523d3f1e423ee41a)
1 /*
2  *	Copied from Linux Monitor (LiMon) - Networking.
3  *
4  *	Copyright 1994 - 2000 Neil Russell.
5  *	(See License)
6  *	Copyright 2000 Roland Borde
7  *	Copyright 2000 Paolo Scaffardi
8  *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
9  *	SPDX-License-Identifier:	GPL-2.0
10  */
11 
12 /*
13  * General Desription:
14  *
15  * The user interface supports commands for BOOTP, RARP, and TFTP.
16  * Also, we support ARP internally. Depending on available data,
17  * these interact as follows:
18  *
19  * BOOTP:
20  *
21  *	Prerequisites:	- own ethernet address
22  *	We want:	- own IP address
23  *			- TFTP server IP address
24  *			- name of bootfile
25  *	Next step:	ARP
26  *
27  * LINK_LOCAL:
28  *
29  *	Prerequisites:	- own ethernet address
30  *	We want:	- own IP address
31  *	Next step:	ARP
32  *
33  * RARP:
34  *
35  *	Prerequisites:	- own ethernet address
36  *	We want:	- own IP address
37  *			- TFTP server IP address
38  *	Next step:	ARP
39  *
40  * ARP:
41  *
42  *	Prerequisites:	- own ethernet address
43  *			- own IP address
44  *			- TFTP server IP address
45  *	We want:	- TFTP server ethernet address
46  *	Next step:	TFTP
47  *
48  * DHCP:
49  *
50  *     Prerequisites:	- own ethernet address
51  *     We want:		- IP, Netmask, ServerIP, Gateway IP
52  *			- bootfilename, lease time
53  *     Next step:	- TFTP
54  *
55  * TFTP:
56  *
57  *	Prerequisites:	- own ethernet address
58  *			- own IP address
59  *			- TFTP server IP address
60  *			- TFTP server ethernet address
61  *			- name of bootfile (if unknown, we use a default name
62  *			  derived from our own IP address)
63  *	We want:	- load the boot file
64  *	Next step:	none
65  *
66  * NFS:
67  *
68  *	Prerequisites:	- own ethernet address
69  *			- own IP address
70  *			- name of bootfile (if unknown, we use a default name
71  *			  derived from our own IP address)
72  *	We want:	- load the boot file
73  *	Next step:	none
74  *
75  * SNTP:
76  *
77  *	Prerequisites:	- own ethernet address
78  *			- own IP address
79  *	We want:	- network time
80  *	Next step:	none
81  */
82 
83 
84 #include <common.h>
85 #include <command.h>
86 #include <environment.h>
87 #include <net.h>
88 #if defined(CONFIG_STATUS_LED)
89 #include <miiphy.h>
90 #include <status_led.h>
91 #endif
92 #include <watchdog.h>
93 #include <linux/compiler.h>
94 #include "arp.h"
95 #include "bootp.h"
96 #include "cdp.h"
97 #if defined(CONFIG_CMD_DNS)
98 #include "dns.h"
99 #endif
100 #include "link_local.h"
101 #include "nfs.h"
102 #include "ping.h"
103 #include "rarp.h"
104 #if defined(CONFIG_CMD_SNTP)
105 #include "sntp.h"
106 #endif
107 #include "tftp.h"
108 
109 DECLARE_GLOBAL_DATA_PTR;
110 
111 /** BOOTP EXTENTIONS **/
112 
113 /* Our subnet mask (0=unknown) */
114 IPaddr_t	NetOurSubnetMask;
115 /* Our gateways IP address */
116 IPaddr_t	NetOurGatewayIP;
117 /* Our DNS IP address */
118 IPaddr_t	NetOurDNSIP;
119 #if defined(CONFIG_BOOTP_DNS2)
120 /* Our 2nd DNS IP address */
121 IPaddr_t	NetOurDNS2IP;
122 #endif
123 /* Our NIS domain */
124 char		NetOurNISDomain[32] = {0,};
125 /* Our hostname */
126 char		NetOurHostName[32] = {0,};
127 /* Our bootpath */
128 char		NetOurRootPath[64] = {0,};
129 /* Our bootfile size in blocks */
130 ushort		NetBootFileSize;
131 
132 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
133 IPaddr_t Mcast_addr;
134 #endif
135 
136 /** END OF BOOTP EXTENTIONS **/
137 
138 /* The actual transferred size of the bootfile (in bytes) */
139 ulong		NetBootFileXferSize;
140 /* Our ethernet address */
141 uchar		NetOurEther[6];
142 /* Boot server enet address */
143 uchar		NetServerEther[6];
144 /* Our IP addr (0 = unknown) */
145 IPaddr_t	NetOurIP;
146 /* Server IP addr (0 = unknown) */
147 IPaddr_t	NetServerIP;
148 /* Current receive packet */
149 uchar *NetRxPacket;
150 /* Current rx packet length */
151 int		NetRxPacketLen;
152 /* IP packet ID */
153 unsigned	NetIPID;
154 /* Ethernet bcast address */
155 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
156 uchar		NetEtherNullAddr[6];
157 #ifdef CONFIG_API
158 void		(*push_packet)(void *, int len) = 0;
159 #endif
160 /* Network loop state */
161 enum net_loop_state net_state;
162 /* Tried all network devices */
163 int		NetRestartWrap;
164 /* Network loop restarted */
165 static int	NetRestarted;
166 /* At least one device configured */
167 static int	NetDevExists;
168 
169 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
170 /* default is without VLAN */
171 ushort		NetOurVLAN = 0xFFFF;
172 /* ditto */
173 ushort		NetOurNativeVLAN = 0xFFFF;
174 
175 /* Boot File name */
176 char		BootFile[128];
177 
178 #if defined(CONFIG_CMD_SNTP)
179 /* NTP server IP address */
180 IPaddr_t	NetNtpServerIP;
181 /* offset time from UTC */
182 int		NetTimeOffset;
183 #endif
184 
185 static uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
186 
187 /* Receive packet */
188 uchar *NetRxPackets[PKTBUFSRX];
189 
190 /* Current UDP RX packet handler */
191 static rxhand_f *udp_packet_handler;
192 /* Current ARP RX packet handler */
193 static rxhand_f *arp_packet_handler;
194 #ifdef CONFIG_CMD_TFTPPUT
195 /* Current ICMP rx handler */
196 static rxhand_icmp_f *packet_icmp_handler;
197 #endif
198 /* Current timeout handler */
199 static thand_f *timeHandler;
200 /* Time base value */
201 static ulong	timeStart;
202 /* Current timeout value */
203 static ulong	timeDelta;
204 /* THE transmit packet */
205 uchar *NetTxPacket;
206 
207 static int net_check_prereq(enum proto_t protocol);
208 
209 static int NetTryCount;
210 
211 int __maybe_unused net_busy_flag;
212 
213 /**********************************************************************/
214 
215 static int on_bootfile(const char *name, const char *value, enum env_op op,
216 	int flags)
217 {
218 	switch (op) {
219 	case env_op_create:
220 	case env_op_overwrite:
221 		copy_filename(BootFile, value, sizeof(BootFile));
222 		break;
223 	default:
224 		break;
225 	}
226 
227 	return 0;
228 }
229 U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
230 
231 /*
232  * Check if autoload is enabled. If so, use either NFS or TFTP to download
233  * the boot file.
234  */
235 void net_auto_load(void)
236 {
237 #if defined(CONFIG_CMD_NFS)
238 	const char *s = getenv("autoload");
239 
240 	if (s != NULL && strcmp(s, "NFS") == 0) {
241 		/*
242 		 * Use NFS to load the bootfile.
243 		 */
244 		NfsStart();
245 		return;
246 	}
247 #endif
248 	if (getenv_yesno("autoload") == 0) {
249 		/*
250 		 * Just use BOOTP/RARP to configure system;
251 		 * Do not use TFTP to load the bootfile.
252 		 */
253 		net_set_state(NETLOOP_SUCCESS);
254 		return;
255 	}
256 	TftpStart(TFTPGET);
257 }
258 
259 static void NetInitLoop(void)
260 {
261 	static int env_changed_id;
262 	int env_id = get_env_id();
263 
264 	/* update only when the environment has changed */
265 	if (env_changed_id != env_id) {
266 		NetOurIP = getenv_IPaddr("ipaddr");
267 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
268 		NetOurSubnetMask = getenv_IPaddr("netmask");
269 		NetServerIP = getenv_IPaddr("serverip");
270 		NetOurNativeVLAN = getenv_VLAN("nvlan");
271 		NetOurVLAN = getenv_VLAN("vlan");
272 #if defined(CONFIG_CMD_DNS)
273 		NetOurDNSIP = getenv_IPaddr("dnsip");
274 #endif
275 		env_changed_id = env_id;
276 	}
277 	if (eth_get_dev())
278 		memcpy(NetOurEther, eth_get_ethaddr(), 6);
279 
280 	return;
281 }
282 
283 static void net_clear_handlers(void)
284 {
285 	net_set_udp_handler(NULL);
286 	net_set_arp_handler(NULL);
287 	NetSetTimeout(0, NULL);
288 }
289 
290 static void net_cleanup_loop(void)
291 {
292 	net_clear_handlers();
293 }
294 
295 void net_init(void)
296 {
297 	static int first_call = 1;
298 
299 	if (first_call) {
300 		/*
301 		 *	Setup packet buffers, aligned correctly.
302 		 */
303 		int i;
304 
305 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
306 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
307 		for (i = 0; i < PKTBUFSRX; i++)
308 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
309 
310 		ArpInit();
311 		net_clear_handlers();
312 
313 		/* Only need to setup buffer pointers once. */
314 		first_call = 0;
315 	}
316 
317 	NetInitLoop();
318 }
319 
320 /**********************************************************************/
321 /*
322  *	Main network processing loop.
323  */
324 
325 int NetLoop(enum proto_t protocol)
326 {
327 	int ret = -1;
328 
329 	NetRestarted = 0;
330 	NetDevExists = 0;
331 	NetTryCount = 1;
332 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
333 
334 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
335 	net_init();
336 	if (eth_is_on_demand_init() || protocol != NETCONS) {
337 		eth_halt();
338 		eth_set_current();
339 		if (eth_init() < 0) {
340 			eth_halt();
341 			return -1;
342 		}
343 	} else
344 		eth_init_state_only();
345 
346 restart:
347 #ifdef CONFIG_USB_KEYBOARD
348 	net_busy_flag = 0;
349 #endif
350 	net_set_state(NETLOOP_CONTINUE);
351 
352 	/*
353 	 *	Start the ball rolling with the given start function.  From
354 	 *	here on, this code is a state machine driven by received
355 	 *	packets and timer events.
356 	 */
357 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
358 	NetInitLoop();
359 
360 	switch (net_check_prereq(protocol)) {
361 	case 1:
362 		/* network not configured */
363 		eth_halt();
364 		return -1;
365 
366 	case 2:
367 		/* network device not configured */
368 		break;
369 
370 	case 0:
371 		NetDevExists = 1;
372 		NetBootFileXferSize = 0;
373 		switch (protocol) {
374 		case TFTPGET:
375 #ifdef CONFIG_CMD_TFTPPUT
376 		case TFTPPUT:
377 #endif
378 			/* always use ARP to get server ethernet address */
379 			TftpStart(protocol);
380 			break;
381 #ifdef CONFIG_CMD_TFTPSRV
382 		case TFTPSRV:
383 			TftpStartServer();
384 			break;
385 #endif
386 #if defined(CONFIG_CMD_DHCP)
387 		case DHCP:
388 			BootpReset();
389 			NetOurIP = 0;
390 			DhcpRequest();		/* Basically same as BOOTP */
391 			break;
392 #endif
393 
394 		case BOOTP:
395 			BootpReset();
396 			NetOurIP = 0;
397 			BootpRequest();
398 			break;
399 
400 #if defined(CONFIG_CMD_RARP)
401 		case RARP:
402 			RarpTry = 0;
403 			NetOurIP = 0;
404 			RarpRequest();
405 			break;
406 #endif
407 #if defined(CONFIG_CMD_PING)
408 		case PING:
409 			ping_start();
410 			break;
411 #endif
412 #if defined(CONFIG_CMD_NFS)
413 		case NFS:
414 			NfsStart();
415 			break;
416 #endif
417 #if defined(CONFIG_CMD_CDP)
418 		case CDP:
419 			CDPStart();
420 			break;
421 #endif
422 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
423 		case NETCONS:
424 			NcStart();
425 			break;
426 #endif
427 #if defined(CONFIG_CMD_SNTP)
428 		case SNTP:
429 			SntpStart();
430 			break;
431 #endif
432 #if defined(CONFIG_CMD_DNS)
433 		case DNS:
434 			DnsStart();
435 			break;
436 #endif
437 #if defined(CONFIG_CMD_LINK_LOCAL)
438 		case LINKLOCAL:
439 			link_local_start();
440 			break;
441 #endif
442 		default:
443 			break;
444 		}
445 
446 		break;
447 	}
448 
449 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
450 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
451 	defined(CONFIG_STATUS_LED)			&& \
452 	defined(STATUS_LED_RED)
453 	/*
454 	 * Echo the inverted link state to the fault LED.
455 	 */
456 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
457 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
458 	else
459 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
460 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
461 #endif /* CONFIG_MII, ... */
462 #ifdef CONFIG_USB_KEYBOARD
463 	net_busy_flag = 1;
464 #endif
465 
466 	/*
467 	 *	Main packet reception loop.  Loop receiving packets until
468 	 *	someone sets `net_state' to a state that terminates.
469 	 */
470 	for (;;) {
471 		WATCHDOG_RESET();
472 #ifdef CONFIG_SHOW_ACTIVITY
473 		show_activity(1);
474 #endif
475 		/*
476 		 *	Check the ethernet for a new packet.  The ethernet
477 		 *	receive routine will process it.
478 		 */
479 		eth_rx();
480 
481 		/*
482 		 *	Abort if ctrl-c was pressed.
483 		 */
484 		if (ctrlc()) {
485 			/* cancel any ARP that may not have completed */
486 			NetArpWaitPacketIP = 0;
487 
488 			net_cleanup_loop();
489 			eth_halt();
490 			/* Invalidate the last protocol */
491 			eth_set_last_protocol(BOOTP);
492 
493 			puts("\nAbort\n");
494 			/* include a debug print as well incase the debug
495 			   messages are directed to stderr */
496 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
497 			goto done;
498 		}
499 
500 		ArpTimeoutCheck();
501 
502 		/*
503 		 *	Check for a timeout, and run the timeout handler
504 		 *	if we have one.
505 		 */
506 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
507 			thand_f *x;
508 
509 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
510 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
511 	defined(CONFIG_STATUS_LED)			&& \
512 	defined(STATUS_LED_RED)
513 			/*
514 			 * Echo the inverted link state to the fault LED.
515 			 */
516 			if (miiphy_link(eth_get_dev()->name,
517 				       CONFIG_SYS_FAULT_MII_ADDR)) {
518 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
519 			} else {
520 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
521 			}
522 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
523 #endif /* CONFIG_MII, ... */
524 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
525 			x = timeHandler;
526 			timeHandler = (thand_f *)0;
527 			(*x)();
528 		}
529 
530 		if (net_state == NETLOOP_FAIL)
531 			NetStartAgain();
532 
533 		switch (net_state) {
534 
535 		case NETLOOP_RESTART:
536 			NetRestarted = 1;
537 			goto restart;
538 
539 		case NETLOOP_SUCCESS:
540 			net_cleanup_loop();
541 			if (NetBootFileXferSize > 0) {
542 				printf("Bytes transferred = %ld (%lx hex)\n",
543 					NetBootFileXferSize,
544 					NetBootFileXferSize);
545 				setenv_hex("filesize", NetBootFileXferSize);
546 				setenv_hex("fileaddr", load_addr);
547 			}
548 			if (protocol != NETCONS)
549 				eth_halt();
550 			else
551 				eth_halt_state_only();
552 
553 			eth_set_last_protocol(protocol);
554 
555 			ret = NetBootFileXferSize;
556 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
557 			goto done;
558 
559 		case NETLOOP_FAIL:
560 			net_cleanup_loop();
561 			/* Invalidate the last protocol */
562 			eth_set_last_protocol(BOOTP);
563 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
564 			goto done;
565 
566 		case NETLOOP_CONTINUE:
567 			continue;
568 		}
569 	}
570 
571 done:
572 #ifdef CONFIG_USB_KEYBOARD
573 	net_busy_flag = 0;
574 #endif
575 #ifdef CONFIG_CMD_TFTPPUT
576 	/* Clear out the handlers */
577 	net_set_udp_handler(NULL);
578 	net_set_icmp_handler(NULL);
579 #endif
580 	return ret;
581 }
582 
583 /**********************************************************************/
584 
585 static void
586 startAgainTimeout(void)
587 {
588 	net_set_state(NETLOOP_RESTART);
589 }
590 
591 void NetStartAgain(void)
592 {
593 	char *nretry;
594 	int retry_forever = 0;
595 	unsigned long retrycnt = 0;
596 
597 	nretry = getenv("netretry");
598 	if (nretry) {
599 		if (!strcmp(nretry, "yes"))
600 			retry_forever = 1;
601 		else if (!strcmp(nretry, "no"))
602 			retrycnt = 0;
603 		else if (!strcmp(nretry, "once"))
604 			retrycnt = 1;
605 		else
606 			retrycnt = simple_strtoul(nretry, NULL, 0);
607 	} else {
608 		retrycnt = 0;
609 		retry_forever = 0;
610 	}
611 
612 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
613 		eth_halt();
614 		net_set_state(NETLOOP_FAIL);
615 		return;
616 	}
617 
618 	NetTryCount++;
619 
620 	eth_halt();
621 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
622 	eth_try_another(!NetRestarted);
623 #endif
624 	eth_init();
625 	if (NetRestartWrap) {
626 		NetRestartWrap = 0;
627 		if (NetDevExists) {
628 			NetSetTimeout(10000UL, startAgainTimeout);
629 			net_set_udp_handler(NULL);
630 		} else {
631 			net_set_state(NETLOOP_FAIL);
632 		}
633 	} else {
634 		net_set_state(NETLOOP_RESTART);
635 	}
636 }
637 
638 /**********************************************************************/
639 /*
640  *	Miscelaneous bits.
641  */
642 
643 static void dummy_handler(uchar *pkt, unsigned dport,
644 			IPaddr_t sip, unsigned sport,
645 			unsigned len)
646 {
647 }
648 
649 rxhand_f *net_get_udp_handler(void)
650 {
651 	return udp_packet_handler;
652 }
653 
654 void net_set_udp_handler(rxhand_f *f)
655 {
656 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
657 	if (f == NULL)
658 		udp_packet_handler = dummy_handler;
659 	else
660 		udp_packet_handler = f;
661 }
662 
663 rxhand_f *net_get_arp_handler(void)
664 {
665 	return arp_packet_handler;
666 }
667 
668 void net_set_arp_handler(rxhand_f *f)
669 {
670 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
671 	if (f == NULL)
672 		arp_packet_handler = dummy_handler;
673 	else
674 		arp_packet_handler = f;
675 }
676 
677 #ifdef CONFIG_CMD_TFTPPUT
678 void net_set_icmp_handler(rxhand_icmp_f *f)
679 {
680 	packet_icmp_handler = f;
681 }
682 #endif
683 
684 void
685 NetSetTimeout(ulong iv, thand_f *f)
686 {
687 	if (iv == 0) {
688 		debug_cond(DEBUG_INT_STATE,
689 			"--- NetLoop timeout handler cancelled\n");
690 		timeHandler = (thand_f *)0;
691 	} else {
692 		debug_cond(DEBUG_INT_STATE,
693 			"--- NetLoop timeout handler set (%p)\n", f);
694 		timeHandler = f;
695 		timeStart = get_timer(0);
696 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
697 	}
698 }
699 
700 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
701 		int payload_len)
702 {
703 	uchar *pkt;
704 	int eth_hdr_size;
705 	int pkt_hdr_size;
706 
707 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
708 	assert(NetTxPacket != NULL);
709 	if (NetTxPacket == NULL)
710 		return -1;
711 
712 	/* convert to new style broadcast */
713 	if (dest == 0)
714 		dest = 0xFFFFFFFF;
715 
716 	/* if broadcast, make the ether address a broadcast and don't do ARP */
717 	if (dest == 0xFFFFFFFF)
718 		ether = NetBcastAddr;
719 
720 	pkt = (uchar *)NetTxPacket;
721 
722 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
723 	pkt += eth_hdr_size;
724 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
725 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
726 
727 	/* if MAC address was not discovered yet, do an ARP request */
728 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
729 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
730 
731 		/* save the ip and eth addr for the packet to send after arp */
732 		NetArpWaitPacketIP = dest;
733 		NetArpWaitPacketMAC = ether;
734 
735 		/* size of the waiting packet */
736 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
737 
738 		/* and do the ARP request */
739 		NetArpWaitTry = 1;
740 		NetArpWaitTimerStart = get_timer(0);
741 		ArpRequest();
742 		return 1;	/* waiting */
743 	} else {
744 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
745 			&dest, ether);
746 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
747 		return 0;	/* transmitted */
748 	}
749 }
750 
751 #ifdef CONFIG_IP_DEFRAG
752 /*
753  * This function collects fragments in a single packet, according
754  * to the algorithm in RFC815. It returns NULL or the pointer to
755  * a complete packet, in static storage
756  */
757 #ifndef CONFIG_NET_MAXDEFRAG
758 #define CONFIG_NET_MAXDEFRAG 16384
759 #endif
760 /*
761  * MAXDEFRAG, above, is chosen in the config file and  is real data
762  * so we need to add the NFS overhead, which is more than TFTP.
763  * To use sizeof in the internal unnamed structures, we need a real
764  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
765  * The compiler doesn't complain nor allocates the actual structure
766  */
767 static struct rpc_t rpc_specimen;
768 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
769 
770 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
771 
772 /*
773  * this is the packet being assembled, either data or frag control.
774  * Fragments go by 8 bytes, so this union must be 8 bytes long
775  */
776 struct hole {
777 	/* first_byte is address of this structure */
778 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
779 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
780 	u16 prev_hole;	/* index of prev, 0 == none */
781 	u16 unused;
782 };
783 
784 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
785 {
786 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
787 	static u16 first_hole, total_len;
788 	struct hole *payload, *thisfrag, *h, *newh;
789 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
790 	uchar *indata = (uchar *)ip;
791 	int offset8, start, len, done = 0;
792 	u16 ip_off = ntohs(ip->ip_off);
793 
794 	/* payload starts after IP header, this fragment is in there */
795 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
796 	offset8 =  (ip_off & IP_OFFS);
797 	thisfrag = payload + offset8;
798 	start = offset8 * 8;
799 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
800 
801 	if (start + len > IP_MAXUDP) /* fragment extends too far */
802 		return NULL;
803 
804 	if (!total_len || localip->ip_id != ip->ip_id) {
805 		/* new (or different) packet, reset structs */
806 		total_len = 0xffff;
807 		payload[0].last_byte = ~0;
808 		payload[0].next_hole = 0;
809 		payload[0].prev_hole = 0;
810 		first_hole = 0;
811 		/* any IP header will work, copy the first we received */
812 		memcpy(localip, ip, IP_HDR_SIZE);
813 	}
814 
815 	/*
816 	 * What follows is the reassembly algorithm. We use the payload
817 	 * array as a linked list of hole descriptors, as each hole starts
818 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
819 	 * so it is represented as byte count, not as 8-byte blocks.
820 	 */
821 
822 	h = payload + first_hole;
823 	while (h->last_byte < start) {
824 		if (!h->next_hole) {
825 			/* no hole that far away */
826 			return NULL;
827 		}
828 		h = payload + h->next_hole;
829 	}
830 
831 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
832 	if (offset8 + ((len + 7) / 8) <= h - payload) {
833 		/* no overlap with holes (dup fragment?) */
834 		return NULL;
835 	}
836 
837 	if (!(ip_off & IP_FLAGS_MFRAG)) {
838 		/* no more fragmentss: truncate this (last) hole */
839 		total_len = start + len;
840 		h->last_byte = start + len;
841 	}
842 
843 	/*
844 	 * There is some overlap: fix the hole list. This code doesn't
845 	 * deal with a fragment that overlaps with two different holes
846 	 * (thus being a superset of a previously-received fragment).
847 	 */
848 
849 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
850 		/* complete overlap with hole: remove hole */
851 		if (!h->prev_hole && !h->next_hole) {
852 			/* last remaining hole */
853 			done = 1;
854 		} else if (!h->prev_hole) {
855 			/* first hole */
856 			first_hole = h->next_hole;
857 			payload[h->next_hole].prev_hole = 0;
858 		} else if (!h->next_hole) {
859 			/* last hole */
860 			payload[h->prev_hole].next_hole = 0;
861 		} else {
862 			/* in the middle of the list */
863 			payload[h->next_hole].prev_hole = h->prev_hole;
864 			payload[h->prev_hole].next_hole = h->next_hole;
865 		}
866 
867 	} else if (h->last_byte <= start + len) {
868 		/* overlaps with final part of the hole: shorten this hole */
869 		h->last_byte = start;
870 
871 	} else if (h >= thisfrag) {
872 		/* overlaps with initial part of the hole: move this hole */
873 		newh = thisfrag + (len / 8);
874 		*newh = *h;
875 		h = newh;
876 		if (h->next_hole)
877 			payload[h->next_hole].prev_hole = (h - payload);
878 		if (h->prev_hole)
879 			payload[h->prev_hole].next_hole = (h - payload);
880 		else
881 			first_hole = (h - payload);
882 
883 	} else {
884 		/* fragment sits in the middle: split the hole */
885 		newh = thisfrag + (len / 8);
886 		*newh = *h;
887 		h->last_byte = start;
888 		h->next_hole = (newh - payload);
889 		newh->prev_hole = (h - payload);
890 		if (newh->next_hole)
891 			payload[newh->next_hole].prev_hole = (newh - payload);
892 	}
893 
894 	/* finally copy this fragment and possibly return whole packet */
895 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
896 	if (!done)
897 		return NULL;
898 
899 	localip->ip_len = htons(total_len);
900 	*lenp = total_len + IP_HDR_SIZE;
901 	return localip;
902 }
903 
904 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
905 {
906 	u16 ip_off = ntohs(ip->ip_off);
907 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
908 		return ip; /* not a fragment */
909 	return __NetDefragment(ip, lenp);
910 }
911 
912 #else /* !CONFIG_IP_DEFRAG */
913 
914 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
915 {
916 	u16 ip_off = ntohs(ip->ip_off);
917 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
918 		return ip; /* not a fragment */
919 	return NULL;
920 }
921 #endif
922 
923 /**
924  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
925  * drop others.
926  *
927  * @parma ip	IP packet containing the ICMP
928  */
929 static void receive_icmp(struct ip_udp_hdr *ip, int len,
930 			IPaddr_t src_ip, struct ethernet_hdr *et)
931 {
932 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
933 
934 	switch (icmph->type) {
935 	case ICMP_REDIRECT:
936 		if (icmph->code != ICMP_REDIR_HOST)
937 			return;
938 		printf(" ICMP Host Redirect to %pI4 ",
939 			&icmph->un.gateway);
940 		break;
941 	default:
942 #if defined(CONFIG_CMD_PING)
943 		ping_receive(et, ip, len);
944 #endif
945 #ifdef CONFIG_CMD_TFTPPUT
946 		if (packet_icmp_handler)
947 			packet_icmp_handler(icmph->type, icmph->code,
948 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
949 				icmph->un.data, ntohs(ip->udp_len));
950 #endif
951 		break;
952 	}
953 }
954 
955 void
956 NetReceive(uchar *inpkt, int len)
957 {
958 	struct ethernet_hdr *et;
959 	struct ip_udp_hdr *ip;
960 	IPaddr_t dst_ip;
961 	IPaddr_t src_ip;
962 	int eth_proto;
963 #if defined(CONFIG_CMD_CDP)
964 	int iscdp;
965 #endif
966 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
967 
968 	debug_cond(DEBUG_NET_PKT, "packet received\n");
969 
970 	NetRxPacket = inpkt;
971 	NetRxPacketLen = len;
972 	et = (struct ethernet_hdr *)inpkt;
973 
974 	/* too small packet? */
975 	if (len < ETHER_HDR_SIZE)
976 		return;
977 
978 #ifdef CONFIG_API
979 	if (push_packet) {
980 		(*push_packet)(inpkt, len);
981 		return;
982 	}
983 #endif
984 
985 #if defined(CONFIG_CMD_CDP)
986 	/* keep track if packet is CDP */
987 	iscdp = is_cdp_packet(et->et_dest);
988 #endif
989 
990 	myvlanid = ntohs(NetOurVLAN);
991 	if (myvlanid == (ushort)-1)
992 		myvlanid = VLAN_NONE;
993 	mynvlanid = ntohs(NetOurNativeVLAN);
994 	if (mynvlanid == (ushort)-1)
995 		mynvlanid = VLAN_NONE;
996 
997 	eth_proto = ntohs(et->et_protlen);
998 
999 	if (eth_proto < 1514) {
1000 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1001 		/*
1002 		 *	Got a 802.2 packet.  Check the other protocol field.
1003 		 *	XXX VLAN over 802.2+SNAP not implemented!
1004 		 */
1005 		eth_proto = ntohs(et802->et_prot);
1006 
1007 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
1008 		len -= E802_HDR_SIZE;
1009 
1010 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
1011 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
1012 		len -= ETHER_HDR_SIZE;
1013 
1014 	} else {			/* VLAN packet */
1015 		struct vlan_ethernet_hdr *vet =
1016 			(struct vlan_ethernet_hdr *)et;
1017 
1018 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1019 
1020 		/* too small packet? */
1021 		if (len < VLAN_ETHER_HDR_SIZE)
1022 			return;
1023 
1024 		/* if no VLAN active */
1025 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1026 #if defined(CONFIG_CMD_CDP)
1027 				&& iscdp == 0
1028 #endif
1029 				)
1030 			return;
1031 
1032 		cti = ntohs(vet->vet_tag);
1033 		vlanid = cti & VLAN_IDMASK;
1034 		eth_proto = ntohs(vet->vet_type);
1035 
1036 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1037 		len -= VLAN_ETHER_HDR_SIZE;
1038 	}
1039 
1040 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1041 
1042 #if defined(CONFIG_CMD_CDP)
1043 	if (iscdp) {
1044 		cdp_receive((uchar *)ip, len);
1045 		return;
1046 	}
1047 #endif
1048 
1049 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1050 		if (vlanid == VLAN_NONE)
1051 			vlanid = (mynvlanid & VLAN_IDMASK);
1052 		/* not matched? */
1053 		if (vlanid != (myvlanid & VLAN_IDMASK))
1054 			return;
1055 	}
1056 
1057 	switch (eth_proto) {
1058 
1059 	case PROT_ARP:
1060 		ArpReceive(et, ip, len);
1061 		break;
1062 
1063 #ifdef CONFIG_CMD_RARP
1064 	case PROT_RARP:
1065 		rarp_receive(ip, len);
1066 		break;
1067 #endif
1068 	case PROT_IP:
1069 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1070 		/* Before we start poking the header, make sure it is there */
1071 		if (len < IP_UDP_HDR_SIZE) {
1072 			debug("len bad %d < %lu\n", len,
1073 				(ulong)IP_UDP_HDR_SIZE);
1074 			return;
1075 		}
1076 		/* Check the packet length */
1077 		if (len < ntohs(ip->ip_len)) {
1078 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1079 			return;
1080 		}
1081 		len = ntohs(ip->ip_len);
1082 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1083 			len, ip->ip_hl_v & 0xff);
1084 
1085 		/* Can't deal with anything except IPv4 */
1086 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1087 			return;
1088 		/* Can't deal with IP options (headers != 20 bytes) */
1089 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1090 			return;
1091 		/* Check the Checksum of the header */
1092 		if (!ip_checksum_ok((uchar *)ip, IP_HDR_SIZE)) {
1093 			debug("checksum bad\n");
1094 			return;
1095 		}
1096 		/* If it is not for us, ignore it */
1097 		dst_ip = NetReadIP(&ip->ip_dst);
1098 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1099 #ifdef CONFIG_MCAST_TFTP
1100 			if (Mcast_addr != dst_ip)
1101 #endif
1102 				return;
1103 		}
1104 		/* Read source IP address for later use */
1105 		src_ip = NetReadIP(&ip->ip_src);
1106 		/*
1107 		 * The function returns the unchanged packet if it's not
1108 		 * a fragment, and either the complete packet or NULL if
1109 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1110 		 */
1111 		ip = NetDefragment(ip, &len);
1112 		if (!ip)
1113 			return;
1114 		/*
1115 		 * watch for ICMP host redirects
1116 		 *
1117 		 * There is no real handler code (yet). We just watch
1118 		 * for ICMP host redirect messages. In case anybody
1119 		 * sees these messages: please contact me
1120 		 * (wd@denx.de), or - even better - send me the
1121 		 * necessary fixes :-)
1122 		 *
1123 		 * Note: in all cases where I have seen this so far
1124 		 * it was a problem with the router configuration,
1125 		 * for instance when a router was configured in the
1126 		 * BOOTP reply, but the TFTP server was on the same
1127 		 * subnet. So this is probably a warning that your
1128 		 * configuration might be wrong. But I'm not really
1129 		 * sure if there aren't any other situations.
1130 		 *
1131 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1132 		 * we send a tftp packet to a dead connection, or when
1133 		 * there is no server at the other end.
1134 		 */
1135 		if (ip->ip_p == IPPROTO_ICMP) {
1136 			receive_icmp(ip, len, src_ip, et);
1137 			return;
1138 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1139 			return;
1140 		}
1141 
1142 		debug_cond(DEBUG_DEV_PKT,
1143 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1144 			&dst_ip, &src_ip, len);
1145 
1146 #ifdef CONFIG_UDP_CHECKSUM
1147 		if (ip->udp_xsum != 0) {
1148 			ulong   xsum;
1149 			ushort *sumptr;
1150 			ushort  sumlen;
1151 
1152 			xsum  = ip->ip_p;
1153 			xsum += (ntohs(ip->udp_len));
1154 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1155 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1156 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1157 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1158 
1159 			sumlen = ntohs(ip->udp_len);
1160 			sumptr = (ushort *) &(ip->udp_src);
1161 
1162 			while (sumlen > 1) {
1163 				ushort sumdata;
1164 
1165 				sumdata = *sumptr++;
1166 				xsum += ntohs(sumdata);
1167 				sumlen -= 2;
1168 			}
1169 			if (sumlen > 0) {
1170 				ushort sumdata;
1171 
1172 				sumdata = *(unsigned char *) sumptr;
1173 				sumdata = (sumdata << 8) & 0xff00;
1174 				xsum += sumdata;
1175 			}
1176 			while ((xsum >> 16) != 0) {
1177 				xsum = (xsum & 0x0000ffff) +
1178 				       ((xsum >> 16) & 0x0000ffff);
1179 			}
1180 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1181 				printf(" UDP wrong checksum %08lx %08x\n",
1182 					xsum, ntohs(ip->udp_xsum));
1183 				return;
1184 			}
1185 		}
1186 #endif
1187 
1188 
1189 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
1190 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1191 					src_ip,
1192 					ntohs(ip->udp_dst),
1193 					ntohs(ip->udp_src),
1194 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1195 #endif
1196 		/*
1197 		 *	IP header OK.  Pass the packet to the current handler.
1198 		 */
1199 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1200 				ntohs(ip->udp_dst),
1201 				src_ip,
1202 				ntohs(ip->udp_src),
1203 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1204 		break;
1205 	}
1206 }
1207 
1208 
1209 /**********************************************************************/
1210 
1211 static int net_check_prereq(enum proto_t protocol)
1212 {
1213 	switch (protocol) {
1214 		/* Fall through */
1215 #if defined(CONFIG_CMD_PING)
1216 	case PING:
1217 		if (NetPingIP == 0) {
1218 			puts("*** ERROR: ping address not given\n");
1219 			return 1;
1220 		}
1221 		goto common;
1222 #endif
1223 #if defined(CONFIG_CMD_SNTP)
1224 	case SNTP:
1225 		if (NetNtpServerIP == 0) {
1226 			puts("*** ERROR: NTP server address not given\n");
1227 			return 1;
1228 		}
1229 		goto common;
1230 #endif
1231 #if defined(CONFIG_CMD_DNS)
1232 	case DNS:
1233 		if (NetOurDNSIP == 0) {
1234 			puts("*** ERROR: DNS server address not given\n");
1235 			return 1;
1236 		}
1237 		goto common;
1238 #endif
1239 #if defined(CONFIG_CMD_NFS)
1240 	case NFS:
1241 #endif
1242 	case TFTPGET:
1243 	case TFTPPUT:
1244 		if (NetServerIP == 0) {
1245 			puts("*** ERROR: `serverip' not set\n");
1246 			return 1;
1247 		}
1248 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1249 	defined(CONFIG_CMD_DNS)
1250 common:
1251 #endif
1252 		/* Fall through */
1253 
1254 	case NETCONS:
1255 	case TFTPSRV:
1256 		if (NetOurIP == 0) {
1257 			puts("*** ERROR: `ipaddr' not set\n");
1258 			return 1;
1259 		}
1260 		/* Fall through */
1261 
1262 #ifdef CONFIG_CMD_RARP
1263 	case RARP:
1264 #endif
1265 	case BOOTP:
1266 	case CDP:
1267 	case DHCP:
1268 	case LINKLOCAL:
1269 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1270 			int num = eth_get_dev_index();
1271 
1272 			switch (num) {
1273 			case -1:
1274 				puts("*** ERROR: No ethernet found.\n");
1275 				return 1;
1276 			case 0:
1277 				puts("*** ERROR: `ethaddr' not set\n");
1278 				break;
1279 			default:
1280 				printf("*** ERROR: `eth%daddr' not set\n",
1281 					num);
1282 				break;
1283 			}
1284 
1285 			NetStartAgain();
1286 			return 2;
1287 		}
1288 		/* Fall through */
1289 	default:
1290 		return 0;
1291 	}
1292 	return 0;		/* OK */
1293 }
1294 /**********************************************************************/
1295 
1296 int
1297 NetEthHdrSize(void)
1298 {
1299 	ushort myvlanid;
1300 
1301 	myvlanid = ntohs(NetOurVLAN);
1302 	if (myvlanid == (ushort)-1)
1303 		myvlanid = VLAN_NONE;
1304 
1305 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1306 		VLAN_ETHER_HDR_SIZE;
1307 }
1308 
1309 int
1310 NetSetEther(uchar *xet, uchar * addr, uint prot)
1311 {
1312 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1313 	ushort myvlanid;
1314 
1315 	myvlanid = ntohs(NetOurVLAN);
1316 	if (myvlanid == (ushort)-1)
1317 		myvlanid = VLAN_NONE;
1318 
1319 	memcpy(et->et_dest, addr, 6);
1320 	memcpy(et->et_src, NetOurEther, 6);
1321 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1322 		et->et_protlen = htons(prot);
1323 		return ETHER_HDR_SIZE;
1324 	} else {
1325 		struct vlan_ethernet_hdr *vet =
1326 			(struct vlan_ethernet_hdr *)xet;
1327 
1328 		vet->vet_vlan_type = htons(PROT_VLAN);
1329 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1330 		vet->vet_type = htons(prot);
1331 		return VLAN_ETHER_HDR_SIZE;
1332 	}
1333 }
1334 
1335 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1336 {
1337 	ushort protlen;
1338 
1339 	memcpy(et->et_dest, addr, 6);
1340 	memcpy(et->et_src, NetOurEther, 6);
1341 	protlen = ntohs(et->et_protlen);
1342 	if (protlen == PROT_VLAN) {
1343 		struct vlan_ethernet_hdr *vet =
1344 			(struct vlan_ethernet_hdr *)et;
1345 		vet->vet_type = htons(prot);
1346 		return VLAN_ETHER_HDR_SIZE;
1347 	} else if (protlen > 1514) {
1348 		et->et_protlen = htons(prot);
1349 		return ETHER_HDR_SIZE;
1350 	} else {
1351 		/* 802.2 + SNAP */
1352 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1353 		et802->et_prot = htons(prot);
1354 		return E802_HDR_SIZE;
1355 	}
1356 }
1357 
1358 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1359 {
1360 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1361 
1362 	/*
1363 	 *	Construct an IP header.
1364 	 */
1365 	/* IP_HDR_SIZE / 4 (not including UDP) */
1366 	ip->ip_hl_v  = 0x45;
1367 	ip->ip_tos   = 0;
1368 	ip->ip_len   = htons(IP_HDR_SIZE);
1369 	ip->ip_id    = htons(NetIPID++);
1370 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1371 	ip->ip_ttl   = 255;
1372 	ip->ip_sum   = 0;
1373 	/* already in network byte order */
1374 	NetCopyIP((void *)&ip->ip_src, &source);
1375 	/* already in network byte order */
1376 	NetCopyIP((void *)&ip->ip_dst, &dest);
1377 }
1378 
1379 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1380 			int len)
1381 {
1382 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1383 
1384 	/*
1385 	 *	If the data is an odd number of bytes, zero the
1386 	 *	byte after the last byte so that the checksum
1387 	 *	will work.
1388 	 */
1389 	if (len & 1)
1390 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1391 
1392 	net_set_ip_header(pkt, dest, NetOurIP);
1393 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1394 	ip->ip_p     = IPPROTO_UDP;
1395 	ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
1396 
1397 	ip->udp_src  = htons(sport);
1398 	ip->udp_dst  = htons(dport);
1399 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1400 	ip->udp_xsum = 0;
1401 }
1402 
1403 void copy_filename(char *dst, const char *src, int size)
1404 {
1405 	if (*src && (*src == '"')) {
1406 		++src;
1407 		--size;
1408 	}
1409 
1410 	while ((--size > 0) && *src && (*src != '"'))
1411 		*dst++ = *src++;
1412 	*dst = '\0';
1413 }
1414 
1415 #if	defined(CONFIG_CMD_NFS)		|| \
1416 	defined(CONFIG_CMD_SNTP)	|| \
1417 	defined(CONFIG_CMD_DNS)
1418 /*
1419  * make port a little random (1024-17407)
1420  * This keeps the math somewhat trivial to compute, and seems to work with
1421  * all supported protocols/clients/servers
1422  */
1423 unsigned int random_port(void)
1424 {
1425 	return 1024 + (get_timer(0) % 0x4000);
1426 }
1427 #endif
1428 
1429 void ip_to_string(IPaddr_t x, char *s)
1430 {
1431 	x = ntohl(x);
1432 	sprintf(s, "%d.%d.%d.%d",
1433 		(int) ((x >> 24) & 0xff),
1434 		(int) ((x >> 16) & 0xff),
1435 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1436 	);
1437 }
1438 
1439 void VLAN_to_string(ushort x, char *s)
1440 {
1441 	x = ntohs(x);
1442 
1443 	if (x == (ushort)-1)
1444 		x = VLAN_NONE;
1445 
1446 	if (x == VLAN_NONE)
1447 		strcpy(s, "none");
1448 	else
1449 		sprintf(s, "%d", x & VLAN_IDMASK);
1450 }
1451 
1452 ushort string_to_VLAN(const char *s)
1453 {
1454 	ushort id;
1455 
1456 	if (s == NULL)
1457 		return htons(VLAN_NONE);
1458 
1459 	if (*s < '0' || *s > '9')
1460 		id = VLAN_NONE;
1461 	else
1462 		id = (ushort)simple_strtoul(s, NULL, 10);
1463 
1464 	return htons(id);
1465 }
1466 
1467 ushort getenv_VLAN(char *var)
1468 {
1469 	return string_to_VLAN(getenv(var));
1470 }
1471