xref: /openbmc/u-boot/net/net.c (revision 4810400e)
1 /*
2  *	Copied from Linux Monitor (LiMon) - Networking.
3  *
4  *	Copyright 1994 - 2000 Neil Russell.
5  *	(See License)
6  *	Copyright 2000 Roland Borde
7  *	Copyright 2000 Paolo Scaffardi
8  *	Copyright 2000-2002 Wolfgang Denk, wd@denx.de
9  */
10 
11 /*
12  * General Desription:
13  *
14  * The user interface supports commands for BOOTP, RARP, and TFTP.
15  * Also, we support ARP internally. Depending on available data,
16  * these interact as follows:
17  *
18  * BOOTP:
19  *
20  *	Prerequisites:	- own ethernet address
21  *	We want:	- own IP address
22  *			- TFTP server IP address
23  *			- name of bootfile
24  *	Next step:	ARP
25  *
26  * LINK_LOCAL:
27  *
28  *	Prerequisites:	- own ethernet address
29  *	We want:	- own IP address
30  *	Next step:	ARP
31  *
32  * RARP:
33  *
34  *	Prerequisites:	- own ethernet address
35  *	We want:	- own IP address
36  *			- TFTP server IP address
37  *	Next step:	ARP
38  *
39  * ARP:
40  *
41  *	Prerequisites:	- own ethernet address
42  *			- own IP address
43  *			- TFTP server IP address
44  *	We want:	- TFTP server ethernet address
45  *	Next step:	TFTP
46  *
47  * DHCP:
48  *
49  *     Prerequisites:	- own ethernet address
50  *     We want:		- IP, Netmask, ServerIP, Gateway IP
51  *			- bootfilename, lease time
52  *     Next step:	- TFTP
53  *
54  * TFTP:
55  *
56  *	Prerequisites:	- own ethernet address
57  *			- own IP address
58  *			- TFTP server IP address
59  *			- TFTP server ethernet address
60  *			- name of bootfile (if unknown, we use a default name
61  *			  derived from our own IP address)
62  *	We want:	- load the boot file
63  *	Next step:	none
64  *
65  * NFS:
66  *
67  *	Prerequisites:	- own ethernet address
68  *			- own IP address
69  *			- name of bootfile (if unknown, we use a default name
70  *			  derived from our own IP address)
71  *	We want:	- load the boot file
72  *	Next step:	none
73  *
74  * SNTP:
75  *
76  *	Prerequisites:	- own ethernet address
77  *			- own IP address
78  *	We want:	- network time
79  *	Next step:	none
80  */
81 
82 
83 #include <common.h>
84 #include <command.h>
85 #include <environment.h>
86 #include <net.h>
87 #if defined(CONFIG_STATUS_LED)
88 #include <miiphy.h>
89 #include <status_led.h>
90 #endif
91 #include <watchdog.h>
92 #include <linux/compiler.h>
93 #include "arp.h"
94 #include "bootp.h"
95 #include "cdp.h"
96 #if defined(CONFIG_CMD_DNS)
97 #include "dns.h"
98 #endif
99 #include "link_local.h"
100 #include "nfs.h"
101 #include "ping.h"
102 #include "rarp.h"
103 #if defined(CONFIG_CMD_SNTP)
104 #include "sntp.h"
105 #endif
106 #include "tftp.h"
107 
108 DECLARE_GLOBAL_DATA_PTR;
109 
110 /** BOOTP EXTENTIONS **/
111 
112 /* Our subnet mask (0=unknown) */
113 IPaddr_t	NetOurSubnetMask;
114 /* Our gateways IP address */
115 IPaddr_t	NetOurGatewayIP;
116 /* Our DNS IP address */
117 IPaddr_t	NetOurDNSIP;
118 #if defined(CONFIG_BOOTP_DNS2)
119 /* Our 2nd DNS IP address */
120 IPaddr_t	NetOurDNS2IP;
121 #endif
122 /* Our NIS domain */
123 char		NetOurNISDomain[32] = {0,};
124 /* Our hostname */
125 char		NetOurHostName[32] = {0,};
126 /* Our bootpath */
127 char		NetOurRootPath[64] = {0,};
128 /* Our bootfile size in blocks */
129 ushort		NetBootFileSize;
130 
131 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
132 IPaddr_t Mcast_addr;
133 #endif
134 
135 /** END OF BOOTP EXTENTIONS **/
136 
137 /* The actual transferred size of the bootfile (in bytes) */
138 ulong		NetBootFileXferSize;
139 /* Our ethernet address */
140 uchar		NetOurEther[6];
141 /* Boot server enet address */
142 uchar		NetServerEther[6];
143 /* Our IP addr (0 = unknown) */
144 IPaddr_t	NetOurIP;
145 /* Server IP addr (0 = unknown) */
146 IPaddr_t	NetServerIP;
147 /* Current receive packet */
148 uchar *NetRxPacket;
149 /* Current rx packet length */
150 int		NetRxPacketLen;
151 /* IP packet ID */
152 unsigned	NetIPID;
153 /* Ethernet bcast address */
154 uchar		NetBcastAddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
155 uchar		NetEtherNullAddr[6];
156 #ifdef CONFIG_API
157 void		(*push_packet)(void *, int len) = 0;
158 #endif
159 /* Network loop state */
160 enum net_loop_state net_state;
161 /* Tried all network devices */
162 int		NetRestartWrap;
163 /* Network loop restarted */
164 static int	NetRestarted;
165 /* At least one device configured */
166 static int	NetDevExists;
167 
168 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
169 /* default is without VLAN */
170 ushort		NetOurVLAN = 0xFFFF;
171 /* ditto */
172 ushort		NetOurNativeVLAN = 0xFFFF;
173 
174 /* Boot File name */
175 char		BootFile[128];
176 
177 #if defined(CONFIG_CMD_SNTP)
178 /* NTP server IP address */
179 IPaddr_t	NetNtpServerIP;
180 /* offset time from UTC */
181 int		NetTimeOffset;
182 #endif
183 
184 static uchar PktBuf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
185 
186 /* Receive packet */
187 uchar *NetRxPackets[PKTBUFSRX];
188 
189 /* Current UDP RX packet handler */
190 static rxhand_f *udp_packet_handler;
191 /* Current ARP RX packet handler */
192 static rxhand_f *arp_packet_handler;
193 #ifdef CONFIG_CMD_TFTPPUT
194 /* Current ICMP rx handler */
195 static rxhand_icmp_f *packet_icmp_handler;
196 #endif
197 /* Current timeout handler */
198 static thand_f *timeHandler;
199 /* Time base value */
200 static ulong	timeStart;
201 /* Current timeout value */
202 static ulong	timeDelta;
203 /* THE transmit packet */
204 uchar *NetTxPacket;
205 
206 static int net_check_prereq(enum proto_t protocol);
207 
208 static int NetTryCount;
209 
210 int __maybe_unused net_busy_flag;
211 
212 /**********************************************************************/
213 
214 static int on_bootfile(const char *name, const char *value, enum env_op op,
215 	int flags)
216 {
217 	switch (op) {
218 	case env_op_create:
219 	case env_op_overwrite:
220 		copy_filename(BootFile, value, sizeof(BootFile));
221 		break;
222 	default:
223 		break;
224 	}
225 
226 	return 0;
227 }
228 U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
229 
230 /*
231  * Check if autoload is enabled. If so, use either NFS or TFTP to download
232  * the boot file.
233  */
234 void net_auto_load(void)
235 {
236 #if defined(CONFIG_CMD_NFS)
237 	const char *s = getenv("autoload");
238 
239 	if (s != NULL && strcmp(s, "NFS") == 0) {
240 		/*
241 		 * Use NFS to load the bootfile.
242 		 */
243 		NfsStart();
244 		return;
245 	}
246 #endif
247 	if (getenv_yesno("autoload") == 0) {
248 		/*
249 		 * Just use BOOTP/RARP to configure system;
250 		 * Do not use TFTP to load the bootfile.
251 		 */
252 		net_set_state(NETLOOP_SUCCESS);
253 		return;
254 	}
255 	TftpStart(TFTPGET);
256 }
257 
258 static void NetInitLoop(void)
259 {
260 	static int env_changed_id;
261 	int env_id = get_env_id();
262 
263 	/* update only when the environment has changed */
264 	if (env_changed_id != env_id) {
265 		NetOurIP = getenv_IPaddr("ipaddr");
266 		NetOurGatewayIP = getenv_IPaddr("gatewayip");
267 		NetOurSubnetMask = getenv_IPaddr("netmask");
268 		NetServerIP = getenv_IPaddr("serverip");
269 		NetOurNativeVLAN = getenv_VLAN("nvlan");
270 		NetOurVLAN = getenv_VLAN("vlan");
271 #if defined(CONFIG_CMD_DNS)
272 		NetOurDNSIP = getenv_IPaddr("dnsip");
273 #endif
274 		env_changed_id = env_id;
275 	}
276 	if (eth_get_dev())
277 		memcpy(NetOurEther, eth_get_dev()->enetaddr, 6);
278 
279 	return;
280 }
281 
282 static void net_clear_handlers(void)
283 {
284 	net_set_udp_handler(NULL);
285 	net_set_arp_handler(NULL);
286 	NetSetTimeout(0, NULL);
287 }
288 
289 static void net_cleanup_loop(void)
290 {
291 	net_clear_handlers();
292 }
293 
294 void net_init(void)
295 {
296 	static int first_call = 1;
297 
298 	if (first_call) {
299 		/*
300 		 *	Setup packet buffers, aligned correctly.
301 		 */
302 		int i;
303 
304 		NetTxPacket = &PktBuf[0] + (PKTALIGN - 1);
305 		NetTxPacket -= (ulong)NetTxPacket % PKTALIGN;
306 		for (i = 0; i < PKTBUFSRX; i++)
307 			NetRxPackets[i] = NetTxPacket + (i + 1) * PKTSIZE_ALIGN;
308 
309 		ArpInit();
310 		net_clear_handlers();
311 
312 		/* Only need to setup buffer pointers once. */
313 		first_call = 0;
314 	}
315 
316 	NetInitLoop();
317 }
318 
319 /**********************************************************************/
320 /*
321  *	Main network processing loop.
322  */
323 
324 int NetLoop(enum proto_t protocol)
325 {
326 	bd_t *bd = gd->bd;
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(bd) < 0) {
340 			eth_halt();
341 			return -1;
342 		}
343 	} else
344 		eth_init_state_only(bd);
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 			BootpTry = 0;
389 			NetOurIP = 0;
390 			DhcpRequest();		/* Basically same as BOOTP */
391 			break;
392 #endif
393 
394 		case BOOTP:
395 			BootpTry = 0;
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 #ifdef CONFIG_NETCONSOLE
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 
531 		switch (net_state) {
532 
533 		case NETLOOP_RESTART:
534 			NetRestarted = 1;
535 			goto restart;
536 
537 		case NETLOOP_SUCCESS:
538 			net_cleanup_loop();
539 			if (NetBootFileXferSize > 0) {
540 				printf("Bytes transferred = %ld (%lx hex)\n",
541 					NetBootFileXferSize,
542 					NetBootFileXferSize);
543 				setenv_hex("filesize", NetBootFileXferSize);
544 				setenv_hex("fileaddr", load_addr);
545 			}
546 			if (protocol != NETCONS)
547 				eth_halt();
548 			else
549 				eth_halt_state_only();
550 
551 			eth_set_last_protocol(protocol);
552 
553 			ret = NetBootFileXferSize;
554 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Success!\n");
555 			goto done;
556 
557 		case NETLOOP_FAIL:
558 			net_cleanup_loop();
559 			/* Invalidate the last protocol */
560 			eth_set_last_protocol(BOOTP);
561 			debug_cond(DEBUG_INT_STATE, "--- NetLoop Fail!\n");
562 			goto done;
563 
564 		case NETLOOP_CONTINUE:
565 			continue;
566 		}
567 	}
568 
569 done:
570 #ifdef CONFIG_USB_KEYBOARD
571 	net_busy_flag = 0;
572 #endif
573 #ifdef CONFIG_CMD_TFTPPUT
574 	/* Clear out the handlers */
575 	net_set_udp_handler(NULL);
576 	net_set_icmp_handler(NULL);
577 #endif
578 	return ret;
579 }
580 
581 /**********************************************************************/
582 
583 static void
584 startAgainTimeout(void)
585 {
586 	net_set_state(NETLOOP_RESTART);
587 }
588 
589 void NetStartAgain(void)
590 {
591 	char *nretry;
592 	int retry_forever = 0;
593 	unsigned long retrycnt = 0;
594 
595 	nretry = getenv("netretry");
596 	if (nretry) {
597 		if (!strcmp(nretry, "yes"))
598 			retry_forever = 1;
599 		else if (!strcmp(nretry, "no"))
600 			retrycnt = 0;
601 		else if (!strcmp(nretry, "once"))
602 			retrycnt = 1;
603 		else
604 			retrycnt = simple_strtoul(nretry, NULL, 0);
605 	} else
606 		retry_forever = 1;
607 
608 	if ((!retry_forever) && (NetTryCount >= retrycnt)) {
609 		eth_halt();
610 		net_set_state(NETLOOP_FAIL);
611 		return;
612 	}
613 
614 	NetTryCount++;
615 
616 	eth_halt();
617 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
618 	eth_try_another(!NetRestarted);
619 #endif
620 	eth_init(gd->bd);
621 	if (NetRestartWrap) {
622 		NetRestartWrap = 0;
623 		if (NetDevExists) {
624 			NetSetTimeout(10000UL, startAgainTimeout);
625 			net_set_udp_handler(NULL);
626 		} else {
627 			net_set_state(NETLOOP_FAIL);
628 		}
629 	} else {
630 		net_set_state(NETLOOP_RESTART);
631 	}
632 }
633 
634 /**********************************************************************/
635 /*
636  *	Miscelaneous bits.
637  */
638 
639 static void dummy_handler(uchar *pkt, unsigned dport,
640 			IPaddr_t sip, unsigned sport,
641 			unsigned len)
642 {
643 }
644 
645 rxhand_f *net_get_udp_handler(void)
646 {
647 	return udp_packet_handler;
648 }
649 
650 void net_set_udp_handler(rxhand_f *f)
651 {
652 	debug_cond(DEBUG_INT_STATE, "--- NetLoop UDP handler set (%p)\n", f);
653 	if (f == NULL)
654 		udp_packet_handler = dummy_handler;
655 	else
656 		udp_packet_handler = f;
657 }
658 
659 rxhand_f *net_get_arp_handler(void)
660 {
661 	return arp_packet_handler;
662 }
663 
664 void net_set_arp_handler(rxhand_f *f)
665 {
666 	debug_cond(DEBUG_INT_STATE, "--- NetLoop ARP handler set (%p)\n", f);
667 	if (f == NULL)
668 		arp_packet_handler = dummy_handler;
669 	else
670 		arp_packet_handler = f;
671 }
672 
673 #ifdef CONFIG_CMD_TFTPPUT
674 void net_set_icmp_handler(rxhand_icmp_f *f)
675 {
676 	packet_icmp_handler = f;
677 }
678 #endif
679 
680 void
681 NetSetTimeout(ulong iv, thand_f *f)
682 {
683 	if (iv == 0) {
684 		debug_cond(DEBUG_INT_STATE,
685 			"--- NetLoop timeout handler cancelled\n");
686 		timeHandler = (thand_f *)0;
687 	} else {
688 		debug_cond(DEBUG_INT_STATE,
689 			"--- NetLoop timeout handler set (%p)\n", f);
690 		timeHandler = f;
691 		timeStart = get_timer(0);
692 		timeDelta = iv * CONFIG_SYS_HZ / 1000;
693 	}
694 }
695 
696 int NetSendUDPPacket(uchar *ether, IPaddr_t dest, int dport, int sport,
697 		int payload_len)
698 {
699 	uchar *pkt;
700 	int eth_hdr_size;
701 	int pkt_hdr_size;
702 
703 	/* make sure the NetTxPacket is initialized (NetInit() was called) */
704 	assert(NetTxPacket != NULL);
705 	if (NetTxPacket == NULL)
706 		return -1;
707 
708 	/* convert to new style broadcast */
709 	if (dest == 0)
710 		dest = 0xFFFFFFFF;
711 
712 	/* if broadcast, make the ether address a broadcast and don't do ARP */
713 	if (dest == 0xFFFFFFFF)
714 		ether = NetBcastAddr;
715 
716 	pkt = (uchar *)NetTxPacket;
717 
718 	eth_hdr_size = NetSetEther(pkt, ether, PROT_IP);
719 	pkt += eth_hdr_size;
720 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
721 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
722 
723 	/* if MAC address was not discovered yet, do an ARP request */
724 	if (memcmp(ether, NetEtherNullAddr, 6) == 0) {
725 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
726 
727 		/* save the ip and eth addr for the packet to send after arp */
728 		NetArpWaitPacketIP = dest;
729 		NetArpWaitPacketMAC = ether;
730 
731 		/* size of the waiting packet */
732 		NetArpWaitTxPacketSize = pkt_hdr_size + payload_len;
733 
734 		/* and do the ARP request */
735 		NetArpWaitTry = 1;
736 		NetArpWaitTimerStart = get_timer(0);
737 		ArpRequest();
738 		return 1;	/* waiting */
739 	} else {
740 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
741 			&dest, ether);
742 		NetSendPacket(NetTxPacket, pkt_hdr_size + payload_len);
743 		return 0;	/* transmitted */
744 	}
745 }
746 
747 #ifdef CONFIG_IP_DEFRAG
748 /*
749  * This function collects fragments in a single packet, according
750  * to the algorithm in RFC815. It returns NULL or the pointer to
751  * a complete packet, in static storage
752  */
753 #ifndef CONFIG_NET_MAXDEFRAG
754 #define CONFIG_NET_MAXDEFRAG 16384
755 #endif
756 /*
757  * MAXDEFRAG, above, is chosen in the config file and  is real data
758  * so we need to add the NFS overhead, which is more than TFTP.
759  * To use sizeof in the internal unnamed structures, we need a real
760  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
761  * The compiler doesn't complain nor allocates the actual structure
762  */
763 static struct rpc_t rpc_specimen;
764 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
765 
766 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
767 
768 /*
769  * this is the packet being assembled, either data or frag control.
770  * Fragments go by 8 bytes, so this union must be 8 bytes long
771  */
772 struct hole {
773 	/* first_byte is address of this structure */
774 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
775 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
776 	u16 prev_hole;	/* index of prev, 0 == none */
777 	u16 unused;
778 };
779 
780 static struct ip_udp_hdr *__NetDefragment(struct ip_udp_hdr *ip, int *lenp)
781 {
782 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
783 	static u16 first_hole, total_len;
784 	struct hole *payload, *thisfrag, *h, *newh;
785 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
786 	uchar *indata = (uchar *)ip;
787 	int offset8, start, len, done = 0;
788 	u16 ip_off = ntohs(ip->ip_off);
789 
790 	/* payload starts after IP header, this fragment is in there */
791 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
792 	offset8 =  (ip_off & IP_OFFS);
793 	thisfrag = payload + offset8;
794 	start = offset8 * 8;
795 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
796 
797 	if (start + len > IP_MAXUDP) /* fragment extends too far */
798 		return NULL;
799 
800 	if (!total_len || localip->ip_id != ip->ip_id) {
801 		/* new (or different) packet, reset structs */
802 		total_len = 0xffff;
803 		payload[0].last_byte = ~0;
804 		payload[0].next_hole = 0;
805 		payload[0].prev_hole = 0;
806 		first_hole = 0;
807 		/* any IP header will work, copy the first we received */
808 		memcpy(localip, ip, IP_HDR_SIZE);
809 	}
810 
811 	/*
812 	 * What follows is the reassembly algorithm. We use the payload
813 	 * array as a linked list of hole descriptors, as each hole starts
814 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
815 	 * so it is represented as byte count, not as 8-byte blocks.
816 	 */
817 
818 	h = payload + first_hole;
819 	while (h->last_byte < start) {
820 		if (!h->next_hole) {
821 			/* no hole that far away */
822 			return NULL;
823 		}
824 		h = payload + h->next_hole;
825 	}
826 
827 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
828 	if (offset8 + ((len + 7) / 8) <= h - payload) {
829 		/* no overlap with holes (dup fragment?) */
830 		return NULL;
831 	}
832 
833 	if (!(ip_off & IP_FLAGS_MFRAG)) {
834 		/* no more fragmentss: truncate this (last) hole */
835 		total_len = start + len;
836 		h->last_byte = start + len;
837 	}
838 
839 	/*
840 	 * There is some overlap: fix the hole list. This code doesn't
841 	 * deal with a fragment that overlaps with two different holes
842 	 * (thus being a superset of a previously-received fragment).
843 	 */
844 
845 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
846 		/* complete overlap with hole: remove hole */
847 		if (!h->prev_hole && !h->next_hole) {
848 			/* last remaining hole */
849 			done = 1;
850 		} else if (!h->prev_hole) {
851 			/* first hole */
852 			first_hole = h->next_hole;
853 			payload[h->next_hole].prev_hole = 0;
854 		} else if (!h->next_hole) {
855 			/* last hole */
856 			payload[h->prev_hole].next_hole = 0;
857 		} else {
858 			/* in the middle of the list */
859 			payload[h->next_hole].prev_hole = h->prev_hole;
860 			payload[h->prev_hole].next_hole = h->next_hole;
861 		}
862 
863 	} else if (h->last_byte <= start + len) {
864 		/* overlaps with final part of the hole: shorten this hole */
865 		h->last_byte = start;
866 
867 	} else if (h >= thisfrag) {
868 		/* overlaps with initial part of the hole: move this hole */
869 		newh = thisfrag + (len / 8);
870 		*newh = *h;
871 		h = newh;
872 		if (h->next_hole)
873 			payload[h->next_hole].prev_hole = (h - payload);
874 		if (h->prev_hole)
875 			payload[h->prev_hole].next_hole = (h - payload);
876 		else
877 			first_hole = (h - payload);
878 
879 	} else {
880 		/* fragment sits in the middle: split the hole */
881 		newh = thisfrag + (len / 8);
882 		*newh = *h;
883 		h->last_byte = start;
884 		h->next_hole = (newh - payload);
885 		newh->prev_hole = (h - payload);
886 		if (newh->next_hole)
887 			payload[newh->next_hole].prev_hole = (newh - payload);
888 	}
889 
890 	/* finally copy this fragment and possibly return whole packet */
891 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
892 	if (!done)
893 		return NULL;
894 
895 	localip->ip_len = htons(total_len);
896 	*lenp = total_len + IP_HDR_SIZE;
897 	return localip;
898 }
899 
900 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
901 {
902 	u16 ip_off = ntohs(ip->ip_off);
903 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
904 		return ip; /* not a fragment */
905 	return __NetDefragment(ip, lenp);
906 }
907 
908 #else /* !CONFIG_IP_DEFRAG */
909 
910 static inline struct ip_udp_hdr *NetDefragment(struct ip_udp_hdr *ip, int *lenp)
911 {
912 	u16 ip_off = ntohs(ip->ip_off);
913 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
914 		return ip; /* not a fragment */
915 	return NULL;
916 }
917 #endif
918 
919 /**
920  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
921  * drop others.
922  *
923  * @parma ip	IP packet containing the ICMP
924  */
925 static void receive_icmp(struct ip_udp_hdr *ip, int len,
926 			IPaddr_t src_ip, struct ethernet_hdr *et)
927 {
928 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
929 
930 	switch (icmph->type) {
931 	case ICMP_REDIRECT:
932 		if (icmph->code != ICMP_REDIR_HOST)
933 			return;
934 		printf(" ICMP Host Redirect to %pI4 ",
935 			&icmph->un.gateway);
936 		break;
937 	default:
938 #if defined(CONFIG_CMD_PING)
939 		ping_receive(et, ip, len);
940 #endif
941 #ifdef CONFIG_CMD_TFTPPUT
942 		if (packet_icmp_handler)
943 			packet_icmp_handler(icmph->type, icmph->code,
944 				ntohs(ip->udp_dst), src_ip, ntohs(ip->udp_src),
945 				icmph->un.data, ntohs(ip->udp_len));
946 #endif
947 		break;
948 	}
949 }
950 
951 void
952 NetReceive(uchar *inpkt, int len)
953 {
954 	struct ethernet_hdr *et;
955 	struct ip_udp_hdr *ip;
956 	IPaddr_t dst_ip;
957 	IPaddr_t src_ip;
958 	int eth_proto;
959 #if defined(CONFIG_CMD_CDP)
960 	int iscdp;
961 #endif
962 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
963 
964 	debug_cond(DEBUG_NET_PKT, "packet received\n");
965 
966 	NetRxPacket = inpkt;
967 	NetRxPacketLen = len;
968 	et = (struct ethernet_hdr *)inpkt;
969 
970 	/* too small packet? */
971 	if (len < ETHER_HDR_SIZE)
972 		return;
973 
974 #ifdef CONFIG_API
975 	if (push_packet) {
976 		(*push_packet)(inpkt, len);
977 		return;
978 	}
979 #endif
980 
981 #if defined(CONFIG_CMD_CDP)
982 	/* keep track if packet is CDP */
983 	iscdp = is_cdp_packet(et->et_dest);
984 #endif
985 
986 	myvlanid = ntohs(NetOurVLAN);
987 	if (myvlanid == (ushort)-1)
988 		myvlanid = VLAN_NONE;
989 	mynvlanid = ntohs(NetOurNativeVLAN);
990 	if (mynvlanid == (ushort)-1)
991 		mynvlanid = VLAN_NONE;
992 
993 	eth_proto = ntohs(et->et_protlen);
994 
995 	if (eth_proto < 1514) {
996 		struct e802_hdr *et802 = (struct e802_hdr *)et;
997 		/*
998 		 *	Got a 802.2 packet.  Check the other protocol field.
999 		 *	XXX VLAN over 802.2+SNAP not implemented!
1000 		 */
1001 		eth_proto = ntohs(et802->et_prot);
1002 
1003 		ip = (struct ip_udp_hdr *)(inpkt + E802_HDR_SIZE);
1004 		len -= E802_HDR_SIZE;
1005 
1006 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
1007 		ip = (struct ip_udp_hdr *)(inpkt + ETHER_HDR_SIZE);
1008 		len -= ETHER_HDR_SIZE;
1009 
1010 	} else {			/* VLAN packet */
1011 		struct vlan_ethernet_hdr *vet =
1012 			(struct vlan_ethernet_hdr *)et;
1013 
1014 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1015 
1016 		/* too small packet? */
1017 		if (len < VLAN_ETHER_HDR_SIZE)
1018 			return;
1019 
1020 		/* if no VLAN active */
1021 		if ((ntohs(NetOurVLAN) & VLAN_IDMASK) == VLAN_NONE
1022 #if defined(CONFIG_CMD_CDP)
1023 				&& iscdp == 0
1024 #endif
1025 				)
1026 			return;
1027 
1028 		cti = ntohs(vet->vet_tag);
1029 		vlanid = cti & VLAN_IDMASK;
1030 		eth_proto = ntohs(vet->vet_type);
1031 
1032 		ip = (struct ip_udp_hdr *)(inpkt + VLAN_ETHER_HDR_SIZE);
1033 		len -= VLAN_ETHER_HDR_SIZE;
1034 	}
1035 
1036 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1037 
1038 #if defined(CONFIG_CMD_CDP)
1039 	if (iscdp) {
1040 		cdp_receive((uchar *)ip, len);
1041 		return;
1042 	}
1043 #endif
1044 
1045 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1046 		if (vlanid == VLAN_NONE)
1047 			vlanid = (mynvlanid & VLAN_IDMASK);
1048 		/* not matched? */
1049 		if (vlanid != (myvlanid & VLAN_IDMASK))
1050 			return;
1051 	}
1052 
1053 	switch (eth_proto) {
1054 
1055 	case PROT_ARP:
1056 		ArpReceive(et, ip, len);
1057 		break;
1058 
1059 #ifdef CONFIG_CMD_RARP
1060 	case PROT_RARP:
1061 		rarp_receive(ip, len);
1062 		break;
1063 #endif
1064 	case PROT_IP:
1065 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1066 		/* Before we start poking the header, make sure it is there */
1067 		if (len < IP_UDP_HDR_SIZE) {
1068 			debug("len bad %d < %lu\n", len,
1069 				(ulong)IP_UDP_HDR_SIZE);
1070 			return;
1071 		}
1072 		/* Check the packet length */
1073 		if (len < ntohs(ip->ip_len)) {
1074 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1075 			return;
1076 		}
1077 		len = ntohs(ip->ip_len);
1078 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1079 			len, ip->ip_hl_v & 0xff);
1080 
1081 		/* Can't deal with anything except IPv4 */
1082 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1083 			return;
1084 		/* Can't deal with IP options (headers != 20 bytes) */
1085 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1086 			return;
1087 		/* Check the Checksum of the header */
1088 		if (!NetCksumOk((uchar *)ip, IP_HDR_SIZE / 2)) {
1089 			debug("checksum bad\n");
1090 			return;
1091 		}
1092 		/* If it is not for us, ignore it */
1093 		dst_ip = NetReadIP(&ip->ip_dst);
1094 		if (NetOurIP && dst_ip != NetOurIP && dst_ip != 0xFFFFFFFF) {
1095 #ifdef CONFIG_MCAST_TFTP
1096 			if (Mcast_addr != dst_ip)
1097 #endif
1098 				return;
1099 		}
1100 		/* Read source IP address for later use */
1101 		src_ip = NetReadIP(&ip->ip_src);
1102 		/*
1103 		 * The function returns the unchanged packet if it's not
1104 		 * a fragment, and either the complete packet or NULL if
1105 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1106 		 */
1107 		ip = NetDefragment(ip, &len);
1108 		if (!ip)
1109 			return;
1110 		/*
1111 		 * watch for ICMP host redirects
1112 		 *
1113 		 * There is no real handler code (yet). We just watch
1114 		 * for ICMP host redirect messages. In case anybody
1115 		 * sees these messages: please contact me
1116 		 * (wd@denx.de), or - even better - send me the
1117 		 * necessary fixes :-)
1118 		 *
1119 		 * Note: in all cases where I have seen this so far
1120 		 * it was a problem with the router configuration,
1121 		 * for instance when a router was configured in the
1122 		 * BOOTP reply, but the TFTP server was on the same
1123 		 * subnet. So this is probably a warning that your
1124 		 * configuration might be wrong. But I'm not really
1125 		 * sure if there aren't any other situations.
1126 		 *
1127 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1128 		 * we send a tftp packet to a dead connection, or when
1129 		 * there is no server at the other end.
1130 		 */
1131 		if (ip->ip_p == IPPROTO_ICMP) {
1132 			receive_icmp(ip, len, src_ip, et);
1133 			return;
1134 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1135 			return;
1136 		}
1137 
1138 		debug_cond(DEBUG_DEV_PKT,
1139 			"received UDP (to=%pI4, from=%pI4, len=%d)\n",
1140 			&dst_ip, &src_ip, len);
1141 
1142 #ifdef CONFIG_UDP_CHECKSUM
1143 		if (ip->udp_xsum != 0) {
1144 			ulong   xsum;
1145 			ushort *sumptr;
1146 			ushort  sumlen;
1147 
1148 			xsum  = ip->ip_p;
1149 			xsum += (ntohs(ip->udp_len));
1150 			xsum += (ntohl(ip->ip_src) >> 16) & 0x0000ffff;
1151 			xsum += (ntohl(ip->ip_src) >>  0) & 0x0000ffff;
1152 			xsum += (ntohl(ip->ip_dst) >> 16) & 0x0000ffff;
1153 			xsum += (ntohl(ip->ip_dst) >>  0) & 0x0000ffff;
1154 
1155 			sumlen = ntohs(ip->udp_len);
1156 			sumptr = (ushort *) &(ip->udp_src);
1157 
1158 			while (sumlen > 1) {
1159 				ushort sumdata;
1160 
1161 				sumdata = *sumptr++;
1162 				xsum += ntohs(sumdata);
1163 				sumlen -= 2;
1164 			}
1165 			if (sumlen > 0) {
1166 				ushort sumdata;
1167 
1168 				sumdata = *(unsigned char *) sumptr;
1169 				sumdata = (sumdata << 8) & 0xff00;
1170 				xsum += sumdata;
1171 			}
1172 			while ((xsum >> 16) != 0) {
1173 				xsum = (xsum & 0x0000ffff) +
1174 				       ((xsum >> 16) & 0x0000ffff);
1175 			}
1176 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1177 				printf(" UDP wrong checksum %08lx %08x\n",
1178 					xsum, ntohs(ip->udp_xsum));
1179 				return;
1180 			}
1181 		}
1182 #endif
1183 
1184 
1185 #ifdef CONFIG_NETCONSOLE
1186 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1187 					src_ip,
1188 					ntohs(ip->udp_dst),
1189 					ntohs(ip->udp_src),
1190 					ntohs(ip->udp_len) - UDP_HDR_SIZE);
1191 #endif
1192 		/*
1193 		 *	IP header OK.  Pass the packet to the current handler.
1194 		 */
1195 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1196 				ntohs(ip->udp_dst),
1197 				src_ip,
1198 				ntohs(ip->udp_src),
1199 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1200 		break;
1201 	}
1202 }
1203 
1204 
1205 /**********************************************************************/
1206 
1207 static int net_check_prereq(enum proto_t protocol)
1208 {
1209 	switch (protocol) {
1210 		/* Fall through */
1211 #if defined(CONFIG_CMD_PING)
1212 	case PING:
1213 		if (NetPingIP == 0) {
1214 			puts("*** ERROR: ping address not given\n");
1215 			return 1;
1216 		}
1217 		goto common;
1218 #endif
1219 #if defined(CONFIG_CMD_SNTP)
1220 	case SNTP:
1221 		if (NetNtpServerIP == 0) {
1222 			puts("*** ERROR: NTP server address not given\n");
1223 			return 1;
1224 		}
1225 		goto common;
1226 #endif
1227 #if defined(CONFIG_CMD_DNS)
1228 	case DNS:
1229 		if (NetOurDNSIP == 0) {
1230 			puts("*** ERROR: DNS server address not given\n");
1231 			return 1;
1232 		}
1233 		goto common;
1234 #endif
1235 #if defined(CONFIG_CMD_NFS)
1236 	case NFS:
1237 #endif
1238 	case TFTPGET:
1239 	case TFTPPUT:
1240 		if (NetServerIP == 0) {
1241 			puts("*** ERROR: `serverip' not set\n");
1242 			return 1;
1243 		}
1244 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1245 	defined(CONFIG_CMD_DNS)
1246 common:
1247 #endif
1248 		/* Fall through */
1249 
1250 	case NETCONS:
1251 	case TFTPSRV:
1252 		if (NetOurIP == 0) {
1253 			puts("*** ERROR: `ipaddr' not set\n");
1254 			return 1;
1255 		}
1256 		/* Fall through */
1257 
1258 #ifdef CONFIG_CMD_RARP
1259 	case RARP:
1260 #endif
1261 	case BOOTP:
1262 	case CDP:
1263 	case DHCP:
1264 	case LINKLOCAL:
1265 		if (memcmp(NetOurEther, "\0\0\0\0\0\0", 6) == 0) {
1266 			int num = eth_get_dev_index();
1267 
1268 			switch (num) {
1269 			case -1:
1270 				puts("*** ERROR: No ethernet found.\n");
1271 				return 1;
1272 			case 0:
1273 				puts("*** ERROR: `ethaddr' not set\n");
1274 				break;
1275 			default:
1276 				printf("*** ERROR: `eth%daddr' not set\n",
1277 					num);
1278 				break;
1279 			}
1280 
1281 			NetStartAgain();
1282 			return 2;
1283 		}
1284 		/* Fall through */
1285 	default:
1286 		return 0;
1287 	}
1288 	return 0;		/* OK */
1289 }
1290 /**********************************************************************/
1291 
1292 int
1293 NetCksumOk(uchar *ptr, int len)
1294 {
1295 	return !((NetCksum(ptr, len) + 1) & 0xfffe);
1296 }
1297 
1298 
1299 unsigned
1300 NetCksum(uchar *ptr, int len)
1301 {
1302 	ulong	xsum;
1303 	ushort *p = (ushort *)ptr;
1304 
1305 	xsum = 0;
1306 	while (len-- > 0)
1307 		xsum += *p++;
1308 	xsum = (xsum & 0xffff) + (xsum >> 16);
1309 	xsum = (xsum & 0xffff) + (xsum >> 16);
1310 	return xsum & 0xffff;
1311 }
1312 
1313 int
1314 NetEthHdrSize(void)
1315 {
1316 	ushort myvlanid;
1317 
1318 	myvlanid = ntohs(NetOurVLAN);
1319 	if (myvlanid == (ushort)-1)
1320 		myvlanid = VLAN_NONE;
1321 
1322 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1323 		VLAN_ETHER_HDR_SIZE;
1324 }
1325 
1326 int
1327 NetSetEther(uchar *xet, uchar * addr, uint prot)
1328 {
1329 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1330 	ushort myvlanid;
1331 
1332 	myvlanid = ntohs(NetOurVLAN);
1333 	if (myvlanid == (ushort)-1)
1334 		myvlanid = VLAN_NONE;
1335 
1336 	memcpy(et->et_dest, addr, 6);
1337 	memcpy(et->et_src, NetOurEther, 6);
1338 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1339 		et->et_protlen = htons(prot);
1340 		return ETHER_HDR_SIZE;
1341 	} else {
1342 		struct vlan_ethernet_hdr *vet =
1343 			(struct vlan_ethernet_hdr *)xet;
1344 
1345 		vet->vet_vlan_type = htons(PROT_VLAN);
1346 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1347 		vet->vet_type = htons(prot);
1348 		return VLAN_ETHER_HDR_SIZE;
1349 	}
1350 }
1351 
1352 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1353 {
1354 	ushort protlen;
1355 
1356 	memcpy(et->et_dest, addr, 6);
1357 	memcpy(et->et_src, NetOurEther, 6);
1358 	protlen = ntohs(et->et_protlen);
1359 	if (protlen == PROT_VLAN) {
1360 		struct vlan_ethernet_hdr *vet =
1361 			(struct vlan_ethernet_hdr *)et;
1362 		vet->vet_type = htons(prot);
1363 		return VLAN_ETHER_HDR_SIZE;
1364 	} else if (protlen > 1514) {
1365 		et->et_protlen = htons(prot);
1366 		return ETHER_HDR_SIZE;
1367 	} else {
1368 		/* 802.2 + SNAP */
1369 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1370 		et802->et_prot = htons(prot);
1371 		return E802_HDR_SIZE;
1372 	}
1373 }
1374 
1375 void net_set_ip_header(uchar *pkt, IPaddr_t dest, IPaddr_t source)
1376 {
1377 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1378 
1379 	/*
1380 	 *	Construct an IP header.
1381 	 */
1382 	/* IP_HDR_SIZE / 4 (not including UDP) */
1383 	ip->ip_hl_v  = 0x45;
1384 	ip->ip_tos   = 0;
1385 	ip->ip_len   = htons(IP_HDR_SIZE);
1386 	ip->ip_id    = htons(NetIPID++);
1387 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1388 	ip->ip_ttl   = 255;
1389 	ip->ip_sum   = 0;
1390 	/* already in network byte order */
1391 	NetCopyIP((void *)&ip->ip_src, &source);
1392 	/* already in network byte order */
1393 	NetCopyIP((void *)&ip->ip_dst, &dest);
1394 }
1395 
1396 void net_set_udp_header(uchar *pkt, IPaddr_t dest, int dport, int sport,
1397 			int len)
1398 {
1399 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1400 
1401 	/*
1402 	 *	If the data is an odd number of bytes, zero the
1403 	 *	byte after the last byte so that the checksum
1404 	 *	will work.
1405 	 */
1406 	if (len & 1)
1407 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1408 
1409 	net_set_ip_header(pkt, dest, NetOurIP);
1410 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1411 	ip->ip_p     = IPPROTO_UDP;
1412 	ip->ip_sum   = ~NetCksum((uchar *)ip, IP_HDR_SIZE >> 1);
1413 
1414 	ip->udp_src  = htons(sport);
1415 	ip->udp_dst  = htons(dport);
1416 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1417 	ip->udp_xsum = 0;
1418 }
1419 
1420 void copy_filename(char *dst, const char *src, int size)
1421 {
1422 	if (*src && (*src == '"')) {
1423 		++src;
1424 		--size;
1425 	}
1426 
1427 	while ((--size > 0) && *src && (*src != '"'))
1428 		*dst++ = *src++;
1429 	*dst = '\0';
1430 }
1431 
1432 #if	defined(CONFIG_CMD_NFS)		|| \
1433 	defined(CONFIG_CMD_SNTP)	|| \
1434 	defined(CONFIG_CMD_DNS)
1435 /*
1436  * make port a little random (1024-17407)
1437  * This keeps the math somewhat trivial to compute, and seems to work with
1438  * all supported protocols/clients/servers
1439  */
1440 unsigned int random_port(void)
1441 {
1442 	return 1024 + (get_timer(0) % 0x4000);
1443 }
1444 #endif
1445 
1446 void ip_to_string(IPaddr_t x, char *s)
1447 {
1448 	x = ntohl(x);
1449 	sprintf(s, "%d.%d.%d.%d",
1450 		(int) ((x >> 24) & 0xff),
1451 		(int) ((x >> 16) & 0xff),
1452 		(int) ((x >> 8) & 0xff), (int) ((x >> 0) & 0xff)
1453 	);
1454 }
1455 
1456 void VLAN_to_string(ushort x, char *s)
1457 {
1458 	x = ntohs(x);
1459 
1460 	if (x == (ushort)-1)
1461 		x = VLAN_NONE;
1462 
1463 	if (x == VLAN_NONE)
1464 		strcpy(s, "none");
1465 	else
1466 		sprintf(s, "%d", x & VLAN_IDMASK);
1467 }
1468 
1469 ushort string_to_VLAN(const char *s)
1470 {
1471 	ushort id;
1472 
1473 	if (s == NULL)
1474 		return htons(VLAN_NONE);
1475 
1476 	if (*s < '0' || *s > '9')
1477 		id = VLAN_NONE;
1478 	else
1479 		id = (ushort)simple_strtoul(s, NULL, 10);
1480 
1481 	return htons(id);
1482 }
1483 
1484 ushort getenv_VLAN(char *var)
1485 {
1486 	return string_to_VLAN(getenv(var));
1487 }
1488