xref: /openbmc/u-boot/net/net.c (revision 52422e37)
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_dev()->enetaddr, 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 	bd_t *bd = gd->bd;
328 	int ret = -1;
329 
330 	NetRestarted = 0;
331 	NetDevExists = 0;
332 	NetTryCount = 1;
333 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Entry\n");
334 
335 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
336 	net_init();
337 	if (eth_is_on_demand_init() || protocol != NETCONS) {
338 		eth_halt();
339 		eth_set_current();
340 		if (eth_init(bd) < 0) {
341 			eth_halt();
342 			return -1;
343 		}
344 	} else
345 		eth_init_state_only(bd);
346 
347 restart:
348 #ifdef CONFIG_USB_KEYBOARD
349 	net_busy_flag = 0;
350 #endif
351 	net_set_state(NETLOOP_CONTINUE);
352 
353 	/*
354 	 *	Start the ball rolling with the given start function.  From
355 	 *	here on, this code is a state machine driven by received
356 	 *	packets and timer events.
357 	 */
358 	debug_cond(DEBUG_INT_STATE, "--- NetLoop Init\n");
359 	NetInitLoop();
360 
361 	switch (net_check_prereq(protocol)) {
362 	case 1:
363 		/* network not configured */
364 		eth_halt();
365 		return -1;
366 
367 	case 2:
368 		/* network device not configured */
369 		break;
370 
371 	case 0:
372 		NetDevExists = 1;
373 		NetBootFileXferSize = 0;
374 		switch (protocol) {
375 		case TFTPGET:
376 #ifdef CONFIG_CMD_TFTPPUT
377 		case TFTPPUT:
378 #endif
379 			/* always use ARP to get server ethernet address */
380 			TftpStart(protocol);
381 			break;
382 #ifdef CONFIG_CMD_TFTPSRV
383 		case TFTPSRV:
384 			TftpStartServer();
385 			break;
386 #endif
387 #if defined(CONFIG_CMD_DHCP)
388 		case DHCP:
389 			BootpReset();
390 			NetOurIP = 0;
391 			DhcpRequest();		/* Basically same as BOOTP */
392 			break;
393 #endif
394 
395 		case BOOTP:
396 			BootpReset();
397 			NetOurIP = 0;
398 			BootpRequest();
399 			break;
400 
401 #if defined(CONFIG_CMD_RARP)
402 		case RARP:
403 			RarpTry = 0;
404 			NetOurIP = 0;
405 			RarpRequest();
406 			break;
407 #endif
408 #if defined(CONFIG_CMD_PING)
409 		case PING:
410 			ping_start();
411 			break;
412 #endif
413 #if defined(CONFIG_CMD_NFS)
414 		case NFS:
415 			NfsStart();
416 			break;
417 #endif
418 #if defined(CONFIG_CMD_CDP)
419 		case CDP:
420 			CDPStart();
421 			break;
422 #endif
423 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
424 		case NETCONS:
425 			NcStart();
426 			break;
427 #endif
428 #if defined(CONFIG_CMD_SNTP)
429 		case SNTP:
430 			SntpStart();
431 			break;
432 #endif
433 #if defined(CONFIG_CMD_DNS)
434 		case DNS:
435 			DnsStart();
436 			break;
437 #endif
438 #if defined(CONFIG_CMD_LINK_LOCAL)
439 		case LINKLOCAL:
440 			link_local_start();
441 			break;
442 #endif
443 		default:
444 			break;
445 		}
446 
447 		break;
448 	}
449 
450 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
451 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
452 	defined(CONFIG_STATUS_LED)			&& \
453 	defined(STATUS_LED_RED)
454 	/*
455 	 * Echo the inverted link state to the fault LED.
456 	 */
457 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
458 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
459 	else
460 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
461 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
462 #endif /* CONFIG_MII, ... */
463 #ifdef CONFIG_USB_KEYBOARD
464 	net_busy_flag = 1;
465 #endif
466 
467 	/*
468 	 *	Main packet reception loop.  Loop receiving packets until
469 	 *	someone sets `net_state' to a state that terminates.
470 	 */
471 	for (;;) {
472 		WATCHDOG_RESET();
473 #ifdef CONFIG_SHOW_ACTIVITY
474 		show_activity(1);
475 #endif
476 		/*
477 		 *	Check the ethernet for a new packet.  The ethernet
478 		 *	receive routine will process it.
479 		 */
480 		eth_rx();
481 
482 		/*
483 		 *	Abort if ctrl-c was pressed.
484 		 */
485 		if (ctrlc()) {
486 			/* cancel any ARP that may not have completed */
487 			NetArpWaitPacketIP = 0;
488 
489 			net_cleanup_loop();
490 			eth_halt();
491 			/* Invalidate the last protocol */
492 			eth_set_last_protocol(BOOTP);
493 
494 			puts("\nAbort\n");
495 			/* include a debug print as well incase the debug
496 			   messages are directed to stderr */
497 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Abort!\n");
498 			goto done;
499 		}
500 
501 		ArpTimeoutCheck();
502 
503 		/*
504 		 *	Check for a timeout, and run the timeout handler
505 		 *	if we have one.
506 		 */
507 		if (timeHandler && ((get_timer(0) - timeStart) > timeDelta)) {
508 			thand_f *x;
509 
510 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
511 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
512 	defined(CONFIG_STATUS_LED)			&& \
513 	defined(STATUS_LED_RED)
514 			/*
515 			 * Echo the inverted link state to the fault LED.
516 			 */
517 			if (miiphy_link(eth_get_dev()->name,
518 				       CONFIG_SYS_FAULT_MII_ADDR)) {
519 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
520 			} else {
521 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
522 			}
523 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
524 #endif /* CONFIG_MII, ... */
525 			debug_cond(DEBUG_INT_STATE, "--- NetLoop timeout\n");
526 			x = timeHandler;
527 			timeHandler = (thand_f *)0;
528 			(*x)();
529 		}
530 
531 
532 		switch (net_state) {
533 
534 		case NETLOOP_RESTART:
535 			NetRestarted = 1;
536 			goto restart;
537 
538 		case NETLOOP_SUCCESS:
539 			net_cleanup_loop();
540 			if (NetBootFileXferSize > 0) {
541 				printf("Bytes transferred = %ld (%lx hex)\n",
542 					NetBootFileXferSize,
543 					NetBootFileXferSize);
544 				setenv_hex("filesize", NetBootFileXferSize);
545 				setenv_hex("fileaddr", load_addr);
546 			}
547 			if (protocol != NETCONS)
548 				eth_halt();
549 			else
550 				eth_halt_state_only();
551 
552 			eth_set_last_protocol(protocol);
553 
554 			ret = NetBootFileXferSize;
555 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
556 			goto done;
557 
558 		case NETLOOP_FAIL:
559 			net_cleanup_loop();
560 			/* Invalidate the last protocol */
561 			eth_set_last_protocol(BOOTP);
562 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
563 			goto done;
564 
565 		case NETLOOP_CONTINUE:
566 			continue;
567 		}
568 	}
569 
570 done:
571 #ifdef CONFIG_USB_KEYBOARD
572 	net_busy_flag = 0;
573 #endif
574 #ifdef CONFIG_CMD_TFTPPUT
575 	/* Clear out the handlers */
576 	net_set_udp_handler(NULL);
577 	net_set_icmp_handler(NULL);
578 #endif
579 	return ret;
580 }
581 
582 /**********************************************************************/
583 
584 static void
585 startAgainTimeout(void)
586 {
587 	net_set_state(NETLOOP_RESTART);
588 }
589 
590 void NetStartAgain(void)
591 {
592 	char *nretry;
593 	int retry_forever = 0;
594 	unsigned long retrycnt = 0;
595 
596 	nretry = getenv("netretry");
597 	if (nretry) {
598 		if (!strcmp(nretry, "yes"))
599 			retry_forever = 1;
600 		else if (!strcmp(nretry, "no"))
601 			retrycnt = 0;
602 		else if (!strcmp(nretry, "once"))
603 			retrycnt = 1;
604 		else
605 			retrycnt = simple_strtoul(nretry, NULL, 0);
606 	} else
607 		retry_forever = 1;
608 
609 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
610 		eth_halt();
611 		net_set_state(NETLOOP_FAIL);
612 		return;
613 	}
614 
615 	NetTryCount++;
616 
617 	eth_halt();
618 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
619 	eth_try_another(!NetRestarted);
620 #endif
621 	eth_init(gd->bd);
622 	if (NetRestartWrap) {
623 		NetRestartWrap = 0;
624 		if (NetDevExists) {
625 			NetSetTimeout(10000UL, startAgainTimeout);
626 			net_set_udp_handler(NULL);
627 		} else {
628 			net_set_state(NETLOOP_FAIL);
629 		}
630 	} else {
631 		net_set_state(NETLOOP_RESTART);
632 	}
633 }
634 
635 /**********************************************************************/
636 /*
637  *	Miscelaneous bits.
638  */
639 
640 static void dummy_handler(uchar *pkt, unsigned dport,
641 			IPaddr_t sip, unsigned sport,
642 			unsigned len)
643 {
644 }
645 
646 rxhand_f *net_get_udp_handler(void)
647 {
648 	return udp_packet_handler;
649 }
650 
651 void net_set_udp_handler(rxhand_f *f)
652 {
653 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
654 	if (f == NULL)
655 		udp_packet_handler = dummy_handler;
656 	else
657 		udp_packet_handler = f;
658 }
659 
660 rxhand_f *net_get_arp_handler(void)
661 {
662 	return arp_packet_handler;
663 }
664 
665 void net_set_arp_handler(rxhand_f *f)
666 {
667 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
668 	if (f == NULL)
669 		arp_packet_handler = dummy_handler;
670 	else
671 		arp_packet_handler = f;
672 }
673 
674 #ifdef CONFIG_CMD_TFTPPUT
675 void net_set_icmp_handler(rxhand_icmp_f *f)
676 {
677 	packet_icmp_handler = f;
678 }
679 #endif
680 
681 void
682 NetSetTimeout(ulong iv, thand_f *f)
683 {
684 	if (iv == 0) {
685 		debug_cond(DEBUG_INT_STATE,
686 			"--- NetLoop timeout handler cancelled\n");
687 		timeHandler = (thand_f *)0;
688 	} else {
689 		debug_cond(DEBUG_INT_STATE,
690 			"--- NetLoop timeout handler set (%p)\n", f);
691 		timeHandler = f;
692 		timeStart = get_timer(0);
693 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
694 	}
695 }
696 
697 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
698 		int payload_len)
699 {
700 	uchar *pkt;
701 	int eth_hdr_size;
702 	int pkt_hdr_size;
703 
704 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
705 	assert(NetTxPacket != NULL);
706 	if (NetTxPacket == NULL)
707 		return -1;
708 
709 	/* convert to new style broadcast */
710 	if (dest == 0)
711 		dest = 0xFFFFFFFF;
712 
713 	/* if broadcast, make the ether address a broadcast and don't do ARP */
714 	if (dest == 0xFFFFFFFF)
715 		ether = NetBcastAddr;
716 
717 	pkt = (uchar *)NetTxPacket;
718 
719 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
720 	pkt += eth_hdr_size;
721 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
722 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
723 
724 	/* if MAC address was not discovered yet, do an ARP request */
725 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
726 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
727 
728 		/* save the ip and eth addr for the packet to send after arp */
729 		NetArpWaitPacketIP = dest;
730 		NetArpWaitPacketMAC = ether;
731 
732 		/* size of the waiting packet */
733 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
734 
735 		/* and do the ARP request */
736 		NetArpWaitTry = 1;
737 		NetArpWaitTimerStart = get_timer(0);
738 		ArpRequest();
739 		return 1;	/* waiting */
740 	} else {
741 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
742 			&dest, ether);
743 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
744 		return 0;	/* transmitted */
745 	}
746 }
747 
748 #ifdef CONFIG_IP_DEFRAG
749 /*
750  * This function collects fragments in a single packet, according
751  * to the algorithm in RFC815. It returns NULL or the pointer to
752  * a complete packet, in static storage
753  */
754 #ifndef CONFIG_NET_MAXDEFRAG
755 #define CONFIG_NET_MAXDEFRAG 16384
756 #endif
757 /*
758  * MAXDEFRAG, above, is chosen in the config file and  is real data
759  * so we need to add the NFS overhead, which is more than TFTP.
760  * To use sizeof in the internal unnamed structures, we need a real
761  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
762  * The compiler doesn't complain nor allocates the actual structure
763  */
764 static struct rpc_t rpc_specimen;
765 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
766 
767 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
768 
769 /*
770  * this is the packet being assembled, either data or frag control.
771  * Fragments go by 8 bytes, so this union must be 8 bytes long
772  */
773 struct hole {
774 	/* first_byte is address of this structure */
775 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
776 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
777 	u16 prev_hole;	/* index of prev, 0 == none */
778 	u16 unused;
779 };
780 
781 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
782 {
783 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
784 	static u16 first_hole, total_len;
785 	struct hole *payload, *thisfrag, *h, *newh;
786 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
787 	uchar *indata = (uchar *)ip;
788 	int offset8, start, len, done = 0;
789 	u16 ip_off = ntohs(ip->ip_off);
790 
791 	/* payload starts after IP header, this fragment is in there */
792 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
793 	offset8 =  (ip_off & IP_OFFS);
794 	thisfrag = payload + offset8;
795 	start = offset8 * 8;
796 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
797 
798 	if (start + len > IP_MAXUDP) /* fragment extends too far */
799 		return NULL;
800 
801 	if (!total_len || localip->ip_id != ip->ip_id) {
802 		/* new (or different) packet, reset structs */
803 		total_len = 0xffff;
804 		payload[0].last_byte = ~0;
805 		payload[0].next_hole = 0;
806 		payload[0].prev_hole = 0;
807 		first_hole = 0;
808 		/* any IP header will work, copy the first we received */
809 		memcpy(localip, ip, IP_HDR_SIZE);
810 	}
811 
812 	/*
813 	 * What follows is the reassembly algorithm. We use the payload
814 	 * array as a linked list of hole descriptors, as each hole starts
815 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
816 	 * so it is represented as byte count, not as 8-byte blocks.
817 	 */
818 
819 	h = payload + first_hole;
820 	while (h->last_byte < start) {
821 		if (!h->next_hole) {
822 			/* no hole that far away */
823 			return NULL;
824 		}
825 		h = payload + h->next_hole;
826 	}
827 
828 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
829 	if (offset8 + ((len + 7) / 8) <= h - payload) {
830 		/* no overlap with holes (dup fragment?) */
831 		return NULL;
832 	}
833 
834 	if (!(ip_off & IP_FLAGS_MFRAG)) {
835 		/* no more fragmentss: truncate this (last) hole */
836 		total_len = start + len;
837 		h->last_byte = start + len;
838 	}
839 
840 	/*
841 	 * There is some overlap: fix the hole list. This code doesn't
842 	 * deal with a fragment that overlaps with two different holes
843 	 * (thus being a superset of a previously-received fragment).
844 	 */
845 
846 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
847 		/* complete overlap with hole: remove hole */
848 		if (!h->prev_hole && !h->next_hole) {
849 			/* last remaining hole */
850 			done = 1;
851 		} else if (!h->prev_hole) {
852 			/* first hole */
853 			first_hole = h->next_hole;
854 			payload[h->next_hole].prev_hole = 0;
855 		} else if (!h->next_hole) {
856 			/* last hole */
857 			payload[h->prev_hole].next_hole = 0;
858 		} else {
859 			/* in the middle of the list */
860 			payload[h->next_hole].prev_hole = h->prev_hole;
861 			payload[h->prev_hole].next_hole = h->next_hole;
862 		}
863 
864 	} else if (h->last_byte <= start + len) {
865 		/* overlaps with final part of the hole: shorten this hole */
866 		h->last_byte = start;
867 
868 	} else if (h >= thisfrag) {
869 		/* overlaps with initial part of the hole: move this hole */
870 		newh = thisfrag + (len / 8);
871 		*newh = *h;
872 		h = newh;
873 		if (h->next_hole)
874 			payload[h->next_hole].prev_hole = (h - payload);
875 		if (h->prev_hole)
876 			payload[h->prev_hole].next_hole = (h - payload);
877 		else
878 			first_hole = (h - payload);
879 
880 	} else {
881 		/* fragment sits in the middle: split the hole */
882 		newh = thisfrag + (len / 8);
883 		*newh = *h;
884 		h->last_byte = start;
885 		h->next_hole = (newh - payload);
886 		newh->prev_hole = (h - payload);
887 		if (newh->next_hole)
888 			payload[newh->next_hole].prev_hole = (newh - payload);
889 	}
890 
891 	/* finally copy this fragment and possibly return whole packet */
892 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
893 	if (!done)
894 		return NULL;
895 
896 	localip->ip_len = htons(total_len);
897 	*lenp = total_len + IP_HDR_SIZE;
898 	return localip;
899 }
900 
901 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
902 {
903 	u16 ip_off = ntohs(ip->ip_off);
904 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
905 		return ip; /* not a fragment */
906 	return __NetDefragment(ip, lenp);
907 }
908 
909 #else /* !CONFIG_IP_DEFRAG */
910 
911 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
912 {
913 	u16 ip_off = ntohs(ip->ip_off);
914 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
915 		return ip; /* not a fragment */
916 	return NULL;
917 }
918 #endif
919 
920 /**
921  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
922  * drop others.
923  *
924  * @parma ip	IP packet containing the ICMP
925  */
926 static void receive_icmp(struct ip_udp_hdr *ip, int len,
927 			IPaddr_t src_ip, struct ethernet_hdr *et)
928 {
929 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
930 
931 	switch (icmph->type) {
932 	case ICMP_REDIRECT:
933 		if (icmph->code != ICMP_REDIR_HOST)
934 			return;
935 		printf(" ICMP Host Redirect to %pI4 ",
936 			&icmph->un.gateway);
937 		break;
938 	default:
939 #if defined(CONFIG_CMD_PING)
940 		ping_receive(et, ip, len);
941 #endif
942 #ifdef CONFIG_CMD_TFTPPUT
943 		if (packet_icmp_handler)
944 			packet_icmp_handler(icmph->type, icmph->code,
945 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
946 				icmph->un.data, ntohs(ip->udp_len));
947 #endif
948 		break;
949 	}
950 }
951 
952 void
953 NetReceive(uchar *inpkt, int len)
954 {
955 	struct ethernet_hdr *et;
956 	struct ip_udp_hdr *ip;
957 	IPaddr_t dst_ip;
958 	IPaddr_t src_ip;
959 	int eth_proto;
960 #if defined(CONFIG_CMD_CDP)
961 	int iscdp;
962 #endif
963 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
964 
965 	debug_cond(DEBUG_NET_PKT, "packet received\n");
966 
967 	NetRxPacket = inpkt;
968 	NetRxPacketLen = len;
969 	et = (struct ethernet_hdr *)inpkt;
970 
971 	/* too small packet? */
972 	if (len < ETHER_HDR_SIZE)
973 		return;
974 
975 #ifdef CONFIG_API
976 	if (push_packet) {
977 		(*push_packet)(inpkt, len);
978 		return;
979 	}
980 #endif
981 
982 #if defined(CONFIG_CMD_CDP)
983 	/* keep track if packet is CDP */
984 	iscdp = is_cdp_packet(et->et_dest);
985 #endif
986 
987 	myvlanid = ntohs(NetOurVLAN);
988 	if (myvlanid == (ushort)-1)
989 		myvlanid = VLAN_NONE;
990 	mynvlanid = ntohs(NetOurNativeVLAN);
991 	if (mynvlanid == (ushort)-1)
992 		mynvlanid = VLAN_NONE;
993 
994 	eth_proto = ntohs(et->et_protlen);
995 
996 	if (eth_proto < 1514) {
997 		struct e802_hdr *et802 = (struct e802_hdr *)et;
998 		/*
999 		 *	Got a 802.2 packet.  Check the other protocol field.
1000 		 *	XXX VLAN over 802.2+SNAP not implemented!
1001 		 */
1002 		eth_proto = ntohs(et802->et_prot);
1003 
1004 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
1005 		len -= E802_HDR_SIZE;
1006 
1007 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
1008 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
1009 		len -= ETHER_HDR_SIZE;
1010 
1011 	} else {			/* VLAN packet */
1012 		struct vlan_ethernet_hdr *vet =
1013 			(struct vlan_ethernet_hdr *)et;
1014 
1015 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1016 
1017 		/* too small packet? */
1018 		if (len < VLAN_ETHER_HDR_SIZE)
1019 			return;
1020 
1021 		/* if no VLAN active */
1022 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1023 #if defined(CONFIG_CMD_CDP)
1024 				&& iscdp == 0
1025 #endif
1026 				)
1027 			return;
1028 
1029 		cti = ntohs(vet->vet_tag);
1030 		vlanid = cti & VLAN_IDMASK;
1031 		eth_proto = ntohs(vet->vet_type);
1032 
1033 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1034 		len -= VLAN_ETHER_HDR_SIZE;
1035 	}
1036 
1037 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1038 
1039 #if defined(CONFIG_CMD_CDP)
1040 	if (iscdp) {
1041 		cdp_receive((uchar *)ip, len);
1042 		return;
1043 	}
1044 #endif
1045 
1046 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1047 		if (vlanid == VLAN_NONE)
1048 			vlanid = (mynvlanid & VLAN_IDMASK);
1049 		/* not matched? */
1050 		if (vlanid != (myvlanid & VLAN_IDMASK))
1051 			return;
1052 	}
1053 
1054 	switch (eth_proto) {
1055 
1056 	case PROT_ARP:
1057 		ArpReceive(et, ip, len);
1058 		break;
1059 
1060 #ifdef CONFIG_CMD_RARP
1061 	case PROT_RARP:
1062 		rarp_receive(ip, len);
1063 		break;
1064 #endif
1065 	case PROT_IP:
1066 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1067 		/* Before we start poking the header, make sure it is there */
1068 		if (len < IP_UDP_HDR_SIZE) {
1069 			debug("len bad %d < %lu\n", len,
1070 				(ulong)IP_UDP_HDR_SIZE);
1071 			return;
1072 		}
1073 		/* Check the packet length */
1074 		if (len < ntohs(ip->ip_len)) {
1075 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1076 			return;
1077 		}
1078 		len = ntohs(ip->ip_len);
1079 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1080 			len, ip->ip_hl_v & 0xff);
1081 
1082 		/* Can't deal with anything except IPv4 */
1083 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1084 			return;
1085 		/* Can't deal with IP options (headers != 20 bytes) */
1086 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1087 			return;
1088 		/* Check the Checksum of the header */
1089 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1090 			debug("checksum bad\n");
1091 			return;
1092 		}
1093 		/* If it is not for us, ignore it */
1094 		dst_ip = NetReadIP(&ip->ip_dst);
1095 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1096 #ifdef CONFIG_MCAST_TFTP
1097 			if (Mcast_addr != dst_ip)
1098 #endif
1099 				return;
1100 		}
1101 		/* Read source IP address for later use */
1102 		src_ip = NetReadIP(&ip->ip_src);
1103 		/*
1104 		 * The function returns the unchanged packet if it's not
1105 		 * a fragment, and either the complete packet or NULL if
1106 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1107 		 */
1108 		ip = NetDefragment(ip, &len);
1109 		if (!ip)
1110 			return;
1111 		/*
1112 		 * watch for ICMP host redirects
1113 		 *
1114 		 * There is no real handler code (yet). We just watch
1115 		 * for ICMP host redirect messages. In case anybody
1116 		 * sees these messages: please contact me
1117 		 * (wd@denx.de), or - even better - send me the
1118 		 * necessary fixes :-)
1119 		 *
1120 		 * Note: in all cases where I have seen this so far
1121 		 * it was a problem with the router configuration,
1122 		 * for instance when a router was configured in the
1123 		 * BOOTP reply, but the TFTP server was on the same
1124 		 * subnet. So this is probably a warning that your
1125 		 * configuration might be wrong. But I'm not really
1126 		 * sure if there aren't any other situations.
1127 		 *
1128 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1129 		 * we send a tftp packet to a dead connection, or when
1130 		 * there is no server at the other end.
1131 		 */
1132 		if (ip->ip_p == IPPROTO_ICMP) {
1133 			receive_icmp(ip, len, src_ip, et);
1134 			return;
1135 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1136 			return;
1137 		}
1138 
1139 		debug_cond(DEBUG_DEV_PKT,
1140 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1141 			&dst_ip, &src_ip, len);
1142 
1143 #ifdef CONFIG_UDP_CHECKSUM
1144 		if (ip->udp_xsum != 0) {
1145 			ulong   xsum;
1146 			ushort *sumptr;
1147 			ushort  sumlen;
1148 
1149 			xsum  = ip->ip_p;
1150 			xsum += (ntohs(ip->udp_len));
1151 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1152 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1153 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1154 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1155 
1156 			sumlen = ntohs(ip->udp_len);
1157 			sumptr = (ushort *) &(ip->udp_src);
1158 
1159 			while (sumlen > 1) {
1160 				ushort sumdata;
1161 
1162 				sumdata = *sumptr++;
1163 				xsum += ntohs(sumdata);
1164 				sumlen -= 2;
1165 			}
1166 			if (sumlen > 0) {
1167 				ushort sumdata;
1168 
1169 				sumdata = *(unsigned char *) sumptr;
1170 				sumdata = (sumdata << 8) & 0xff00;
1171 				xsum += sumdata;
1172 			}
1173 			while ((xsum >> 16) != 0) {
1174 				xsum = (xsum & 0x0000ffff) +
1175 				       ((xsum >> 16) & 0x0000ffff);
1176 			}
1177 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1178 				printf(" UDP wrong checksum %08lx %08x\n",
1179 					xsum, ntohs(ip->udp_xsum));
1180 				return;
1181 			}
1182 		}
1183 #endif
1184 
1185 
1186 #if defined (CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
1187 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1188 					src_ip,
1189 					ntohs(ip->udp_dst),
1190 					ntohs(ip->udp_src),
1191 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1192 #endif
1193 		/*
1194 		 *	IP header OK.  Pass the packet to the current handler.
1195 		 */
1196 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1197 				ntohs(ip->udp_dst),
1198 				src_ip,
1199 				ntohs(ip->udp_src),
1200 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1201 		break;
1202 	}
1203 }
1204 
1205 
1206 /**********************************************************************/
1207 
1208 static int net_check_prereq(enum proto_t protocol)
1209 {
1210 	switch (protocol) {
1211 		/* Fall through */
1212 #if defined(CONFIG_CMD_PING)
1213 	case PING:
1214 		if (NetPingIP == 0) {
1215 			puts("*** ERROR: ping address not given\n");
1216 			return 1;
1217 		}
1218 		goto common;
1219 #endif
1220 #if defined(CONFIG_CMD_SNTP)
1221 	case SNTP:
1222 		if (NetNtpServerIP == 0) {
1223 			puts("*** ERROR: NTP server address not given\n");
1224 			return 1;
1225 		}
1226 		goto common;
1227 #endif
1228 #if defined(CONFIG_CMD_DNS)
1229 	case DNS:
1230 		if (NetOurDNSIP == 0) {
1231 			puts("*** ERROR: DNS server address not given\n");
1232 			return 1;
1233 		}
1234 		goto common;
1235 #endif
1236 #if defined(CONFIG_CMD_NFS)
1237 	case NFS:
1238 #endif
1239 	case TFTPGET:
1240 	case TFTPPUT:
1241 		if (NetServerIP == 0) {
1242 			puts("*** ERROR: `serverip' not set\n");
1243 			return 1;
1244 		}
1245 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1246 	defined(CONFIG_CMD_DNS)
1247 common:
1248 #endif
1249 		/* Fall through */
1250 
1251 	case NETCONS:
1252 	case TFTPSRV:
1253 		if (NetOurIP == 0) {
1254 			puts("*** ERROR: `ipaddr' not set\n");
1255 			return 1;
1256 		}
1257 		/* Fall through */
1258 
1259 #ifdef CONFIG_CMD_RARP
1260 	case RARP:
1261 #endif
1262 	case BOOTP:
1263 	case CDP:
1264 	case DHCP:
1265 	case LINKLOCAL:
1266 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1267 			int num = eth_get_dev_index();
1268 
1269 			switch (num) {
1270 			case -1:
1271 				puts("*** ERROR: No ethernet found.\n");
1272 				return 1;
1273 			case 0:
1274 				puts("*** ERROR: `ethaddr' not set\n");
1275 				break;
1276 			default:
1277 				printf("*** ERROR: `eth%daddr' not set\n",
1278 					num);
1279 				break;
1280 			}
1281 
1282 			NetStartAgain();
1283 			return 2;
1284 		}
1285 		/* Fall through */
1286 	default:
1287 		return 0;
1288 	}
1289 	return 0;		/* OK */
1290 }
1291 /**********************************************************************/
1292 
1293 int
1294 NetCksumOk(uchar *ptr, int len)
1295 {
1296 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1297 }
1298 
1299 
1300 unsigned
1301 NetCksum(uchar *ptr, int len)
1302 {
1303 	ulong	xsum;
1304 	ushort *p = (ushort *)ptr;
1305 
1306 	xsum = 0;
1307 	while (len-- > 0)
1308 		xsum += *p++;
1309 	xsum = (xsum & 0xffff) + (xsum >> 16);
1310 	xsum = (xsum & 0xffff) + (xsum >> 16);
1311 	return xsum & 0xffff;
1312 }
1313 
1314 int
1315 NetEthHdrSize(void)
1316 {
1317 	ushort myvlanid;
1318 
1319 	myvlanid = ntohs(NetOurVLAN);
1320 	if (myvlanid == (ushort)-1)
1321 		myvlanid = VLAN_NONE;
1322 
1323 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1324 		VLAN_ETHER_HDR_SIZE;
1325 }
1326 
1327 int
1328 NetSetEther(uchar *xet, uchar * addr, uint prot)
1329 {
1330 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1331 	ushort myvlanid;
1332 
1333 	myvlanid = ntohs(NetOurVLAN);
1334 	if (myvlanid == (ushort)-1)
1335 		myvlanid = VLAN_NONE;
1336 
1337 	memcpy(et->et_dest, addr, 6);
1338 	memcpy(et->et_src, NetOurEther, 6);
1339 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1340 		et->et_protlen = htons(prot);
1341 		return ETHER_HDR_SIZE;
1342 	} else {
1343 		struct vlan_ethernet_hdr *vet =
1344 			(struct vlan_ethernet_hdr *)xet;
1345 
1346 		vet->vet_vlan_type = htons(PROT_VLAN);
1347 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1348 		vet->vet_type = htons(prot);
1349 		return VLAN_ETHER_HDR_SIZE;
1350 	}
1351 }
1352 
1353 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1354 {
1355 	ushort protlen;
1356 
1357 	memcpy(et->et_dest, addr, 6);
1358 	memcpy(et->et_src, NetOurEther, 6);
1359 	protlen = ntohs(et->et_protlen);
1360 	if (protlen == PROT_VLAN) {
1361 		struct vlan_ethernet_hdr *vet =
1362 			(struct vlan_ethernet_hdr *)et;
1363 		vet->vet_type = htons(prot);
1364 		return VLAN_ETHER_HDR_SIZE;
1365 	} else if (protlen > 1514) {
1366 		et->et_protlen = htons(prot);
1367 		return ETHER_HDR_SIZE;
1368 	} else {
1369 		/* 802.2 + SNAP */
1370 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1371 		et802->et_prot = htons(prot);
1372 		return E802_HDR_SIZE;
1373 	}
1374 }
1375 
1376 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1377 {
1378 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1379 
1380 	/*
1381 	 *	Construct an IP header.
1382 	 */
1383 	/* IP_HDR_SIZE / 4 (not including UDP) */
1384 	ip->ip_hl_v  = 0x45;
1385 	ip->ip_tos   = 0;
1386 	ip->ip_len   = htons(IP_HDR_SIZE);
1387 	ip->ip_id    = htons(NetIPID++);
1388 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1389 	ip->ip_ttl   = 255;
1390 	ip->ip_sum   = 0;
1391 	/* already in network byte order */
1392 	NetCopyIP((void *)&ip->ip_src, &source);
1393 	/* already in network byte order */
1394 	NetCopyIP((void *)&ip->ip_dst, &dest);
1395 }
1396 
1397 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1398 			int len)
1399 {
1400 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1401 
1402 	/*
1403 	 *	If the data is an odd number of bytes, zero the
1404 	 *	byte after the last byte so that the checksum
1405 	 *	will work.
1406 	 */
1407 	if (len & 1)
1408 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1409 
1410 	net_set_ip_header(pkt, dest, NetOurIP);
1411 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1412 	ip->ip_p     = IPPROTO_UDP;
1413 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1414 
1415 	ip->udp_src  = htons(sport);
1416 	ip->udp_dst  = htons(dport);
1417 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1418 	ip->udp_xsum = 0;
1419 }
1420 
1421 void copy_filename(char *dst, const char *src, int size)
1422 {
1423 	if (*src && (*src == '"')) {
1424 		++src;
1425 		--size;
1426 	}
1427 
1428 	while ((--size > 0) && *src && (*src != '"'))
1429 		*dst++ = *src++;
1430 	*dst = '\0';
1431 }
1432 
1433 #if	defined(CONFIG_CMD_NFS)		|| \
1434 	defined(CONFIG_CMD_SNTP)	|| \
1435 	defined(CONFIG_CMD_DNS)
1436 /*
1437  * make port a little random (1024-17407)
1438  * This keeps the math somewhat trivial to compute, and seems to work with
1439  * all supported protocols/clients/servers
1440  */
1441 unsigned int random_port(void)
1442 {
1443 	return 1024 + (get_timer(0) % 0x4000);
1444 }
1445 #endif
1446 
1447 void ip_to_string(IPaddr_t x, char *s)
1448 {
1449 	x = ntohl(x);
1450 	sprintf(s, "%d.%d.%d.%d",
1451 		(int) ((x >> 24) & 0xff),
1452 		(int) ((x >> 16) & 0xff),
1453 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1454 	);
1455 }
1456 
1457 void VLAN_to_string(ushort x, char *s)
1458 {
1459 	x = ntohs(x);
1460 
1461 	if (x == (ushort)-1)
1462 		x = VLAN_NONE;
1463 
1464 	if (x == VLAN_NONE)
1465 		strcpy(s, "none");
1466 	else
1467 		sprintf(s, "%d", x & VLAN_IDMASK);
1468 }
1469 
1470 ushort string_to_VLAN(const char *s)
1471 {
1472 	ushort id;
1473 
1474 	if (s == NULL)
1475 		return htons(VLAN_NONE);
1476 
1477 	if (*s < '0' || *s > '9')
1478 		id = VLAN_NONE;
1479 	else
1480 		id = (ushort)simple_strtoul(s, NULL, 10);
1481 
1482 	return htons(id);
1483 }
1484 
1485 ushort getenv_VLAN(char *var)
1486 {
1487 	return string_to_VLAN(getenv(var));
1488 }
1489