xref: /openbmc/u-boot/net/net.c (revision 11a69ff85b0a459f4ac096ae054d0b527d44b095)
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 <errno.h>
88 #include <net.h>
89 #include <net/tftp.h>
90 #if defined(CONFIG_STATUS_LED)
91 #include <miiphy.h>
92 #include <status_led.h>
93 #endif
94 #include <watchdog.h>
95 #include <linux/compiler.h>
96 #include "arp.h"
97 #include "bootp.h"
98 #include "cdp.h"
99 #if defined(CONFIG_CMD_DNS)
100 #include "dns.h"
101 #endif
102 #include "link_local.h"
103 #include "nfs.h"
104 #include "ping.h"
105 #include "rarp.h"
106 #if defined(CONFIG_CMD_SNTP)
107 #include "sntp.h"
108 #endif
109 
110 DECLARE_GLOBAL_DATA_PTR;
111 
112 /** BOOTP EXTENTIONS **/
113 
114 /* Our subnet mask (0=unknown) */
115 struct in_addr net_netmask;
116 /* Our gateways IP address */
117 struct in_addr net_gateway;
118 /* Our DNS IP address */
119 struct in_addr net_dns_server;
120 #if defined(CONFIG_BOOTP_DNS2)
121 /* Our 2nd DNS IP address */
122 struct in_addr net_dns_server2;
123 #endif
124 
125 #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
126 struct in_addr net_mcast_addr;
127 #endif
128 
129 /** END OF BOOTP EXTENTIONS **/
130 
131 /* Our ethernet address */
132 u8 net_ethaddr[6];
133 /* Boot server enet address */
134 u8 net_server_ethaddr[6];
135 /* Our IP addr (0 = unknown) */
136 struct in_addr	net_ip;
137 /* Server IP addr (0 = unknown) */
138 struct in_addr	net_server_ip;
139 /* Current receive packet */
140 uchar *net_rx_packet;
141 /* Current rx packet length */
142 int		net_rx_packet_len;
143 /* IP packet ID */
144 static unsigned	net_ip_id;
145 /* Ethernet bcast address */
146 const u8 net_bcast_ethaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
147 const u8 net_null_ethaddr[6];
148 #ifdef CONFIG_API
149 void (*push_packet)(void *, int len) = 0;
150 #endif
151 /* Network loop state */
152 enum net_loop_state net_state;
153 /* Tried all network devices */
154 int		net_restart_wrap;
155 /* Network loop restarted */
156 static int	net_restarted;
157 /* At least one device configured */
158 static int	net_dev_exists;
159 
160 /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
161 /* default is without VLAN */
162 ushort		net_our_vlan = 0xFFFF;
163 /* ditto */
164 ushort		net_native_vlan = 0xFFFF;
165 
166 /* Boot File name */
167 char net_boot_file_name[1024];
168 /* The actual transferred size of the bootfile (in bytes) */
169 u32 net_boot_file_size;
170 /* Boot file size in blocks as reported by the DHCP server */
171 u32 net_boot_file_expected_size_in_blocks;
172 
173 #if defined(CONFIG_CMD_SNTP)
174 /* NTP server IP address */
175 struct in_addr	net_ntp_server;
176 /* offset time from UTC */
177 int		net_ntp_time_offset;
178 #endif
179 
180 static uchar net_pkt_buf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
181 /* Receive packets */
182 uchar *net_rx_packets[PKTBUFSRX];
183 /* Current UDP RX packet handler */
184 static rxhand_f *udp_packet_handler;
185 /* Current ARP RX packet handler */
186 static rxhand_f *arp_packet_handler;
187 #ifdef CONFIG_CMD_TFTPPUT
188 /* Current ICMP rx handler */
189 static rxhand_icmp_f *packet_icmp_handler;
190 #endif
191 /* Current timeout handler */
192 static thand_f *time_handler;
193 /* Time base value */
194 static ulong	time_start;
195 /* Current timeout value */
196 static ulong	time_delta;
197 /* THE transmit packet */
198 uchar *net_tx_packet;
199 
200 static int net_check_prereq(enum proto_t protocol);
201 
202 static int net_try_count;
203 
204 int __maybe_unused net_busy_flag;
205 
206 /**********************************************************************/
207 
208 static int on_bootfile(const char *name, const char *value, enum env_op op,
209 	int flags)
210 {
211 	if (flags & H_PROGRAMMATIC)
212 		return 0;
213 
214 	switch (op) {
215 	case env_op_create:
216 	case env_op_overwrite:
217 		copy_filename(net_boot_file_name, value,
218 			      sizeof(net_boot_file_name));
219 		break;
220 	default:
221 		break;
222 	}
223 
224 	return 0;
225 }
226 U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
227 
228 static int on_ipaddr(const char *name, const char *value, enum env_op op,
229 	int flags)
230 {
231 	if (flags & H_PROGRAMMATIC)
232 		return 0;
233 
234 	net_ip = string_to_ip(value);
235 
236 	return 0;
237 }
238 U_BOOT_ENV_CALLBACK(ipaddr, on_ipaddr);
239 
240 static int on_gatewayip(const char *name, const char *value, enum env_op op,
241 	int flags)
242 {
243 	if (flags & H_PROGRAMMATIC)
244 		return 0;
245 
246 	net_gateway = string_to_ip(value);
247 
248 	return 0;
249 }
250 U_BOOT_ENV_CALLBACK(gatewayip, on_gatewayip);
251 
252 static int on_netmask(const char *name, const char *value, enum env_op op,
253 	int flags)
254 {
255 	if (flags & H_PROGRAMMATIC)
256 		return 0;
257 
258 	net_netmask = string_to_ip(value);
259 
260 	return 0;
261 }
262 U_BOOT_ENV_CALLBACK(netmask, on_netmask);
263 
264 static int on_serverip(const char *name, const char *value, enum env_op op,
265 	int flags)
266 {
267 	if (flags & H_PROGRAMMATIC)
268 		return 0;
269 
270 	net_server_ip = string_to_ip(value);
271 
272 	return 0;
273 }
274 U_BOOT_ENV_CALLBACK(serverip, on_serverip);
275 
276 static int on_nvlan(const char *name, const char *value, enum env_op op,
277 	int flags)
278 {
279 	if (flags & H_PROGRAMMATIC)
280 		return 0;
281 
282 	net_native_vlan = string_to_vlan(value);
283 
284 	return 0;
285 }
286 U_BOOT_ENV_CALLBACK(nvlan, on_nvlan);
287 
288 static int on_vlan(const char *name, const char *value, enum env_op op,
289 	int flags)
290 {
291 	if (flags & H_PROGRAMMATIC)
292 		return 0;
293 
294 	net_our_vlan = string_to_vlan(value);
295 
296 	return 0;
297 }
298 U_BOOT_ENV_CALLBACK(vlan, on_vlan);
299 
300 #if defined(CONFIG_CMD_DNS)
301 static int on_dnsip(const char *name, const char *value, enum env_op op,
302 	int flags)
303 {
304 	if (flags & H_PROGRAMMATIC)
305 		return 0;
306 
307 	net_dns_server = string_to_ip(value);
308 
309 	return 0;
310 }
311 U_BOOT_ENV_CALLBACK(dnsip, on_dnsip);
312 #endif
313 
314 /*
315  * Check if autoload is enabled. If so, use either NFS or TFTP to download
316  * the boot file.
317  */
318 void net_auto_load(void)
319 {
320 #if defined(CONFIG_CMD_NFS)
321 	const char *s = getenv("autoload");
322 
323 	if (s != NULL && strcmp(s, "NFS") == 0) {
324 		/*
325 		 * Use NFS to load the bootfile.
326 		 */
327 		nfs_start();
328 		return;
329 	}
330 #endif
331 	if (getenv_yesno("autoload") == 0) {
332 		/*
333 		 * Just use BOOTP/RARP to configure system;
334 		 * Do not use TFTP to load the bootfile.
335 		 */
336 		net_set_state(NETLOOP_SUCCESS);
337 		return;
338 	}
339 	tftp_start(TFTPGET);
340 }
341 
342 static void net_init_loop(void)
343 {
344 	if (eth_get_dev())
345 		memcpy(net_ethaddr, eth_get_ethaddr(), 6);
346 
347 	return;
348 }
349 
350 static void net_clear_handlers(void)
351 {
352 	net_set_udp_handler(NULL);
353 	net_set_arp_handler(NULL);
354 	net_set_timeout_handler(0, NULL);
355 }
356 
357 static void net_cleanup_loop(void)
358 {
359 	net_clear_handlers();
360 }
361 
362 void net_init(void)
363 {
364 	static int first_call = 1;
365 
366 	if (first_call) {
367 		/*
368 		 *	Setup packet buffers, aligned correctly.
369 		 */
370 		int i;
371 
372 		net_tx_packet = &net_pkt_buf[0] + (PKTALIGN - 1);
373 		net_tx_packet -= (ulong)net_tx_packet % PKTALIGN;
374 		for (i = 0; i < PKTBUFSRX; i++) {
375 			net_rx_packets[i] = net_tx_packet +
376 				(i + 1) * PKTSIZE_ALIGN;
377 		}
378 		arp_init();
379 		net_clear_handlers();
380 
381 		/* Only need to setup buffer pointers once. */
382 		first_call = 0;
383 	}
384 
385 	net_init_loop();
386 }
387 
388 /**********************************************************************/
389 /*
390  *	Main network processing loop.
391  */
392 
393 int net_loop(enum proto_t protocol)
394 {
395 	int ret = -EINVAL;
396 
397 	net_restarted = 0;
398 	net_dev_exists = 0;
399 	net_try_count = 1;
400 	debug_cond(DEBUG_INT_STATE, "--- net_loop Entry\n");
401 
402 	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
403 	net_init();
404 	if (eth_is_on_demand_init() || protocol != NETCONS) {
405 		eth_halt();
406 		eth_set_current();
407 		ret = eth_init();
408 		if (ret < 0) {
409 			eth_halt();
410 			return ret;
411 		}
412 	} else {
413 		eth_init_state_only();
414 	}
415 restart:
416 #ifdef CONFIG_USB_KEYBOARD
417 	net_busy_flag = 0;
418 #endif
419 	net_set_state(NETLOOP_CONTINUE);
420 
421 	/*
422 	 *	Start the ball rolling with the given start function.  From
423 	 *	here on, this code is a state machine driven by received
424 	 *	packets and timer events.
425 	 */
426 	debug_cond(DEBUG_INT_STATE, "--- net_loop Init\n");
427 	net_init_loop();
428 
429 	switch (net_check_prereq(protocol)) {
430 	case 1:
431 		/* network not configured */
432 		eth_halt();
433 		return -ENODEV;
434 
435 	case 2:
436 		/* network device not configured */
437 		break;
438 
439 	case 0:
440 		net_dev_exists = 1;
441 		net_boot_file_size = 0;
442 		switch (protocol) {
443 		case TFTPGET:
444 #ifdef CONFIG_CMD_TFTPPUT
445 		case TFTPPUT:
446 #endif
447 			/* always use ARP to get server ethernet address */
448 			tftp_start(protocol);
449 			break;
450 #ifdef CONFIG_CMD_TFTPSRV
451 		case TFTPSRV:
452 			tftp_start_server();
453 			break;
454 #endif
455 #if defined(CONFIG_CMD_DHCP)
456 		case DHCP:
457 			bootp_reset();
458 			net_ip.s_addr = 0;
459 			dhcp_request();		/* Basically same as BOOTP */
460 			break;
461 #endif
462 
463 		case BOOTP:
464 			bootp_reset();
465 			net_ip.s_addr = 0;
466 			bootp_request();
467 			break;
468 
469 #if defined(CONFIG_CMD_RARP)
470 		case RARP:
471 			rarp_try = 0;
472 			net_ip.s_addr = 0;
473 			rarp_request();
474 			break;
475 #endif
476 #if defined(CONFIG_CMD_PING)
477 		case PING:
478 			ping_start();
479 			break;
480 #endif
481 #if defined(CONFIG_CMD_NFS)
482 		case NFS:
483 			nfs_start();
484 			break;
485 #endif
486 #if defined(CONFIG_CMD_CDP)
487 		case CDP:
488 			cdp_start();
489 			break;
490 #endif
491 #if defined(CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
492 		case NETCONS:
493 			nc_start();
494 			break;
495 #endif
496 #if defined(CONFIG_CMD_SNTP)
497 		case SNTP:
498 			sntp_start();
499 			break;
500 #endif
501 #if defined(CONFIG_CMD_DNS)
502 		case DNS:
503 			dns_start();
504 			break;
505 #endif
506 #if defined(CONFIG_CMD_LINK_LOCAL)
507 		case LINKLOCAL:
508 			link_local_start();
509 			break;
510 #endif
511 		default:
512 			break;
513 		}
514 
515 		break;
516 	}
517 
518 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
519 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
520 	defined(CONFIG_STATUS_LED)			&& \
521 	defined(STATUS_LED_RED)
522 	/*
523 	 * Echo the inverted link state to the fault LED.
524 	 */
525 	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
526 		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
527 	else
528 		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
529 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
530 #endif /* CONFIG_MII, ... */
531 #ifdef CONFIG_USB_KEYBOARD
532 	net_busy_flag = 1;
533 #endif
534 
535 	/*
536 	 *	Main packet reception loop.  Loop receiving packets until
537 	 *	someone sets `net_state' to a state that terminates.
538 	 */
539 	for (;;) {
540 		WATCHDOG_RESET();
541 #ifdef CONFIG_SHOW_ACTIVITY
542 		show_activity(1);
543 #endif
544 		/*
545 		 *	Check the ethernet for a new packet.  The ethernet
546 		 *	receive routine will process it.
547 		 *	Most drivers return the most recent packet size, but not
548 		 *	errors that may have happened.
549 		 */
550 		eth_rx();
551 
552 		/*
553 		 *	Abort if ctrl-c was pressed.
554 		 */
555 		if (ctrlc()) {
556 			/* cancel any ARP that may not have completed */
557 			net_arp_wait_packet_ip.s_addr = 0;
558 
559 			net_cleanup_loop();
560 			eth_halt();
561 			/* Invalidate the last protocol */
562 			eth_set_last_protocol(BOOTP);
563 
564 			puts("\nAbort\n");
565 			/* include a debug print as well incase the debug
566 			   messages are directed to stderr */
567 			debug_cond(DEBUG_INT_STATE, "--- net_loop Abort!\n");
568 			ret = -EINTR;
569 			goto done;
570 		}
571 
572 		if (arp_timeout_check() > 0) {
573 		    time_start = get_timer(0);
574 		}
575 
576 		/*
577 		 *	Check for a timeout, and run the timeout handler
578 		 *	if we have one.
579 		 */
580 		if (time_handler &&
581 		    ((get_timer(0) - time_start) > time_delta)) {
582 			thand_f *x;
583 
584 #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
585 #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
586 	defined(CONFIG_STATUS_LED)			&& \
587 	defined(STATUS_LED_RED)
588 			/*
589 			 * Echo the inverted link state to the fault LED.
590 			 */
591 			if (miiphy_link(eth_get_dev()->name,
592 					CONFIG_SYS_FAULT_MII_ADDR))
593 				status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
594 			else
595 				status_led_set(STATUS_LED_RED, STATUS_LED_ON);
596 #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
597 #endif /* CONFIG_MII, ... */
598 			debug_cond(DEBUG_INT_STATE, "--- net_loop timeout\n");
599 			x = time_handler;
600 			time_handler = (thand_f *)0;
601 			(*x)();
602 		}
603 
604 		if (net_state == NETLOOP_FAIL)
605 			ret = net_start_again();
606 
607 		switch (net_state) {
608 		case NETLOOP_RESTART:
609 			net_restarted = 1;
610 			goto restart;
611 
612 		case NETLOOP_SUCCESS:
613 			net_cleanup_loop();
614 			if (net_boot_file_size > 0) {
615 				printf("Bytes transferred = %d (%x hex)\n",
616 				       net_boot_file_size, net_boot_file_size);
617 				setenv_hex("filesize", net_boot_file_size);
618 				setenv_hex("fileaddr", load_addr);
619 			}
620 			if (protocol != NETCONS)
621 				eth_halt();
622 			else
623 				eth_halt_state_only();
624 
625 			eth_set_last_protocol(protocol);
626 
627 			ret = net_boot_file_size;
628 			debug_cond(DEBUG_INT_STATE, "--- net_loop Success!\n");
629 			goto done;
630 
631 		case NETLOOP_FAIL:
632 			net_cleanup_loop();
633 			/* Invalidate the last protocol */
634 			eth_set_last_protocol(BOOTP);
635 			debug_cond(DEBUG_INT_STATE, "--- net_loop Fail!\n");
636 			goto done;
637 
638 		case NETLOOP_CONTINUE:
639 			continue;
640 		}
641 	}
642 
643 done:
644 #ifdef CONFIG_USB_KEYBOARD
645 	net_busy_flag = 0;
646 #endif
647 #ifdef CONFIG_CMD_TFTPPUT
648 	/* Clear out the handlers */
649 	net_set_udp_handler(NULL);
650 	net_set_icmp_handler(NULL);
651 #endif
652 	return ret;
653 }
654 
655 /**********************************************************************/
656 
657 static void start_again_timeout_handler(void)
658 {
659 	net_set_state(NETLOOP_RESTART);
660 }
661 
662 int net_start_again(void)
663 {
664 	char *nretry;
665 	int retry_forever = 0;
666 	unsigned long retrycnt = 0;
667 	int ret;
668 
669 	nretry = getenv("netretry");
670 	if (nretry) {
671 		if (!strcmp(nretry, "yes"))
672 			retry_forever = 1;
673 		else if (!strcmp(nretry, "no"))
674 			retrycnt = 0;
675 		else if (!strcmp(nretry, "once"))
676 			retrycnt = 1;
677 		else
678 			retrycnt = simple_strtoul(nretry, NULL, 0);
679 	} else {
680 		retrycnt = 0;
681 		retry_forever = 0;
682 	}
683 
684 	if ((!retry_forever) && (net_try_count >= retrycnt)) {
685 		eth_halt();
686 		net_set_state(NETLOOP_FAIL);
687 		/*
688 		 * We don't provide a way for the protocol to return an error,
689 		 * but this is almost always the reason.
690 		 */
691 		return -ETIMEDOUT;
692 	}
693 
694 	net_try_count++;
695 
696 	eth_halt();
697 #if !defined(CONFIG_NET_DO_NOT_TRY_ANOTHER)
698 	eth_try_another(!net_restarted);
699 #endif
700 	ret = eth_init();
701 	if (net_restart_wrap) {
702 		net_restart_wrap = 0;
703 		if (net_dev_exists) {
704 			net_set_timeout_handler(10000UL,
705 						start_again_timeout_handler);
706 			net_set_udp_handler(NULL);
707 		} else {
708 			net_set_state(NETLOOP_FAIL);
709 		}
710 	} else {
711 		net_set_state(NETLOOP_RESTART);
712 	}
713 	return ret;
714 }
715 
716 /**********************************************************************/
717 /*
718  *	Miscelaneous bits.
719  */
720 
721 static void dummy_handler(uchar *pkt, unsigned dport,
722 			struct in_addr sip, unsigned sport,
723 			unsigned len)
724 {
725 }
726 
727 rxhand_f *net_get_udp_handler(void)
728 {
729 	return udp_packet_handler;
730 }
731 
732 void net_set_udp_handler(rxhand_f *f)
733 {
734 	debug_cond(DEBUG_INT_STATE, "--- net_loop UDP handler set (%p)\n", f);
735 	if (f == NULL)
736 		udp_packet_handler = dummy_handler;
737 	else
738 		udp_packet_handler = f;
739 }
740 
741 rxhand_f *net_get_arp_handler(void)
742 {
743 	return arp_packet_handler;
744 }
745 
746 void net_set_arp_handler(rxhand_f *f)
747 {
748 	debug_cond(DEBUG_INT_STATE, "--- net_loop ARP handler set (%p)\n", f);
749 	if (f == NULL)
750 		arp_packet_handler = dummy_handler;
751 	else
752 		arp_packet_handler = f;
753 }
754 
755 #ifdef CONFIG_CMD_TFTPPUT
756 void net_set_icmp_handler(rxhand_icmp_f *f)
757 {
758 	packet_icmp_handler = f;
759 }
760 #endif
761 
762 void net_set_timeout_handler(ulong iv, thand_f *f)
763 {
764 	if (iv == 0) {
765 		debug_cond(DEBUG_INT_STATE,
766 			   "--- net_loop timeout handler cancelled\n");
767 		time_handler = (thand_f *)0;
768 	} else {
769 		debug_cond(DEBUG_INT_STATE,
770 			   "--- net_loop timeout handler set (%p)\n", f);
771 		time_handler = f;
772 		time_start = get_timer(0);
773 		time_delta = iv * CONFIG_SYS_HZ / 1000;
774 	}
775 }
776 
777 int net_send_udp_packet(uchar *ether, struct in_addr dest, int dport, int sport,
778 		int payload_len)
779 {
780 	uchar *pkt;
781 	int eth_hdr_size;
782 	int pkt_hdr_size;
783 
784 	/* make sure the net_tx_packet is initialized (net_init() was called) */
785 	assert(net_tx_packet != NULL);
786 	if (net_tx_packet == NULL)
787 		return -1;
788 
789 	/* convert to new style broadcast */
790 	if (dest.s_addr == 0)
791 		dest.s_addr = 0xFFFFFFFF;
792 
793 	/* if broadcast, make the ether address a broadcast and don't do ARP */
794 	if (dest.s_addr == 0xFFFFFFFF)
795 		ether = (uchar *)net_bcast_ethaddr;
796 
797 	pkt = (uchar *)net_tx_packet;
798 
799 	eth_hdr_size = net_set_ether(pkt, ether, PROT_IP);
800 	pkt += eth_hdr_size;
801 	net_set_udp_header(pkt, dest, dport, sport, payload_len);
802 	pkt_hdr_size = eth_hdr_size + IP_UDP_HDR_SIZE;
803 
804 	/* if MAC address was not discovered yet, do an ARP request */
805 	if (memcmp(ether, net_null_ethaddr, 6) == 0) {
806 		debug_cond(DEBUG_DEV_PKT, "sending ARP for %pI4\n", &dest);
807 
808 		/* save the ip and eth addr for the packet to send after arp */
809 		net_arp_wait_packet_ip = dest;
810 		arp_wait_packet_ethaddr = ether;
811 
812 		/* size of the waiting packet */
813 		arp_wait_tx_packet_size = pkt_hdr_size + payload_len;
814 
815 		/* and do the ARP request */
816 		arp_wait_try = 1;
817 		arp_wait_timer_start = get_timer(0);
818 		arp_request();
819 		return 1;	/* waiting */
820 	} else {
821 		debug_cond(DEBUG_DEV_PKT, "sending UDP to %pI4/%pM\n",
822 			   &dest, ether);
823 		net_send_packet(net_tx_packet, pkt_hdr_size + payload_len);
824 		return 0;	/* transmitted */
825 	}
826 }
827 
828 #ifdef CONFIG_IP_DEFRAG
829 /*
830  * This function collects fragments in a single packet, according
831  * to the algorithm in RFC815. It returns NULL or the pointer to
832  * a complete packet, in static storage
833  */
834 #ifndef CONFIG_NET_MAXDEFRAG
835 #define CONFIG_NET_MAXDEFRAG 16384
836 #endif
837 /*
838  * MAXDEFRAG, above, is chosen in the config file and  is real data
839  * so we need to add the NFS overhead, which is more than TFTP.
840  * To use sizeof in the internal unnamed structures, we need a real
841  * instance (can't do "sizeof(struct rpc_t.u.reply))", unfortunately).
842  * The compiler doesn't complain nor allocates the actual structure
843  */
844 static struct rpc_t rpc_specimen;
845 #define IP_PKTSIZE (CONFIG_NET_MAXDEFRAG + sizeof(rpc_specimen.u.reply))
846 
847 #define IP_MAXUDP (IP_PKTSIZE - IP_HDR_SIZE)
848 
849 /*
850  * this is the packet being assembled, either data or frag control.
851  * Fragments go by 8 bytes, so this union must be 8 bytes long
852  */
853 struct hole {
854 	/* first_byte is address of this structure */
855 	u16 last_byte;	/* last byte in this hole + 1 (begin of next hole) */
856 	u16 next_hole;	/* index of next (in 8-b blocks), 0 == none */
857 	u16 prev_hole;	/* index of prev, 0 == none */
858 	u16 unused;
859 };
860 
861 static struct ip_udp_hdr *__net_defragment(struct ip_udp_hdr *ip, int *lenp)
862 {
863 	static uchar pkt_buff[IP_PKTSIZE] __aligned(PKTALIGN);
864 	static u16 first_hole, total_len;
865 	struct hole *payload, *thisfrag, *h, *newh;
866 	struct ip_udp_hdr *localip = (struct ip_udp_hdr *)pkt_buff;
867 	uchar *indata = (uchar *)ip;
868 	int offset8, start, len, done = 0;
869 	u16 ip_off = ntohs(ip->ip_off);
870 
871 	/* payload starts after IP header, this fragment is in there */
872 	payload = (struct hole *)(pkt_buff + IP_HDR_SIZE);
873 	offset8 =  (ip_off & IP_OFFS);
874 	thisfrag = payload + offset8;
875 	start = offset8 * 8;
876 	len = ntohs(ip->ip_len) - IP_HDR_SIZE;
877 
878 	if (start + len > IP_MAXUDP) /* fragment extends too far */
879 		return NULL;
880 
881 	if (!total_len || localip->ip_id != ip->ip_id) {
882 		/* new (or different) packet, reset structs */
883 		total_len = 0xffff;
884 		payload[0].last_byte = ~0;
885 		payload[0].next_hole = 0;
886 		payload[0].prev_hole = 0;
887 		first_hole = 0;
888 		/* any IP header will work, copy the first we received */
889 		memcpy(localip, ip, IP_HDR_SIZE);
890 	}
891 
892 	/*
893 	 * What follows is the reassembly algorithm. We use the payload
894 	 * array as a linked list of hole descriptors, as each hole starts
895 	 * at a multiple of 8 bytes. However, last byte can be whatever value,
896 	 * so it is represented as byte count, not as 8-byte blocks.
897 	 */
898 
899 	h = payload + first_hole;
900 	while (h->last_byte < start) {
901 		if (!h->next_hole) {
902 			/* no hole that far away */
903 			return NULL;
904 		}
905 		h = payload + h->next_hole;
906 	}
907 
908 	/* last fragment may be 1..7 bytes, the "+7" forces acceptance */
909 	if (offset8 + ((len + 7) / 8) <= h - payload) {
910 		/* no overlap with holes (dup fragment?) */
911 		return NULL;
912 	}
913 
914 	if (!(ip_off & IP_FLAGS_MFRAG)) {
915 		/* no more fragmentss: truncate this (last) hole */
916 		total_len = start + len;
917 		h->last_byte = start + len;
918 	}
919 
920 	/*
921 	 * There is some overlap: fix the hole list. This code doesn't
922 	 * deal with a fragment that overlaps with two different holes
923 	 * (thus being a superset of a previously-received fragment).
924 	 */
925 
926 	if ((h >= thisfrag) && (h->last_byte <= start + len)) {
927 		/* complete overlap with hole: remove hole */
928 		if (!h->prev_hole && !h->next_hole) {
929 			/* last remaining hole */
930 			done = 1;
931 		} else if (!h->prev_hole) {
932 			/* first hole */
933 			first_hole = h->next_hole;
934 			payload[h->next_hole].prev_hole = 0;
935 		} else if (!h->next_hole) {
936 			/* last hole */
937 			payload[h->prev_hole].next_hole = 0;
938 		} else {
939 			/* in the middle of the list */
940 			payload[h->next_hole].prev_hole = h->prev_hole;
941 			payload[h->prev_hole].next_hole = h->next_hole;
942 		}
943 
944 	} else if (h->last_byte <= start + len) {
945 		/* overlaps with final part of the hole: shorten this hole */
946 		h->last_byte = start;
947 
948 	} else if (h >= thisfrag) {
949 		/* overlaps with initial part of the hole: move this hole */
950 		newh = thisfrag + (len / 8);
951 		*newh = *h;
952 		h = newh;
953 		if (h->next_hole)
954 			payload[h->next_hole].prev_hole = (h - payload);
955 		if (h->prev_hole)
956 			payload[h->prev_hole].next_hole = (h - payload);
957 		else
958 			first_hole = (h - payload);
959 
960 	} else {
961 		/* fragment sits in the middle: split the hole */
962 		newh = thisfrag + (len / 8);
963 		*newh = *h;
964 		h->last_byte = start;
965 		h->next_hole = (newh - payload);
966 		newh->prev_hole = (h - payload);
967 		if (newh->next_hole)
968 			payload[newh->next_hole].prev_hole = (newh - payload);
969 	}
970 
971 	/* finally copy this fragment and possibly return whole packet */
972 	memcpy((uchar *)thisfrag, indata + IP_HDR_SIZE, len);
973 	if (!done)
974 		return NULL;
975 
976 	localip->ip_len = htons(total_len);
977 	*lenp = total_len + IP_HDR_SIZE;
978 	return localip;
979 }
980 
981 static inline struct ip_udp_hdr *net_defragment(struct ip_udp_hdr *ip,
982 	int *lenp)
983 {
984 	u16 ip_off = ntohs(ip->ip_off);
985 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
986 		return ip; /* not a fragment */
987 	return __net_defragment(ip, lenp);
988 }
989 
990 #else /* !CONFIG_IP_DEFRAG */
991 
992 static inline struct ip_udp_hdr *net_defragment(struct ip_udp_hdr *ip,
993 	int *lenp)
994 {
995 	u16 ip_off = ntohs(ip->ip_off);
996 	if (!(ip_off & (IP_OFFS | IP_FLAGS_MFRAG)))
997 		return ip; /* not a fragment */
998 	return NULL;
999 }
1000 #endif
1001 
1002 /**
1003  * Receive an ICMP packet. We deal with REDIRECT and PING here, and silently
1004  * drop others.
1005  *
1006  * @parma ip	IP packet containing the ICMP
1007  */
1008 static void receive_icmp(struct ip_udp_hdr *ip, int len,
1009 			struct in_addr src_ip, struct ethernet_hdr *et)
1010 {
1011 	struct icmp_hdr *icmph = (struct icmp_hdr *)&ip->udp_src;
1012 
1013 	switch (icmph->type) {
1014 	case ICMP_REDIRECT:
1015 		if (icmph->code != ICMP_REDIR_HOST)
1016 			return;
1017 		printf(" ICMP Host Redirect to %pI4 ",
1018 		       &icmph->un.gateway);
1019 		break;
1020 	default:
1021 #if defined(CONFIG_CMD_PING)
1022 		ping_receive(et, ip, len);
1023 #endif
1024 #ifdef CONFIG_CMD_TFTPPUT
1025 		if (packet_icmp_handler)
1026 			packet_icmp_handler(icmph->type, icmph->code,
1027 					    ntohs(ip->udp_dst), src_ip,
1028 					    ntohs(ip->udp_src), icmph->un.data,
1029 					    ntohs(ip->udp_len));
1030 #endif
1031 		break;
1032 	}
1033 }
1034 
1035 void net_process_received_packet(uchar *in_packet, int len)
1036 {
1037 	struct ethernet_hdr *et;
1038 	struct ip_udp_hdr *ip;
1039 	struct in_addr dst_ip;
1040 	struct in_addr src_ip;
1041 	int eth_proto;
1042 #if defined(CONFIG_CMD_CDP)
1043 	int iscdp;
1044 #endif
1045 	ushort cti = 0, vlanid = VLAN_NONE, myvlanid, mynvlanid;
1046 
1047 	debug_cond(DEBUG_NET_PKT, "packet received\n");
1048 
1049 	net_rx_packet = in_packet;
1050 	net_rx_packet_len = len;
1051 	et = (struct ethernet_hdr *)in_packet;
1052 
1053 	/* too small packet? */
1054 	if (len < ETHER_HDR_SIZE)
1055 		return;
1056 
1057 #ifdef CONFIG_API
1058 	if (push_packet) {
1059 		(*push_packet)(in_packet, len);
1060 		return;
1061 	}
1062 #endif
1063 
1064 #if defined(CONFIG_CMD_CDP)
1065 	/* keep track if packet is CDP */
1066 	iscdp = is_cdp_packet(et->et_dest);
1067 #endif
1068 
1069 	myvlanid = ntohs(net_our_vlan);
1070 	if (myvlanid == (ushort)-1)
1071 		myvlanid = VLAN_NONE;
1072 	mynvlanid = ntohs(net_native_vlan);
1073 	if (mynvlanid == (ushort)-1)
1074 		mynvlanid = VLAN_NONE;
1075 
1076 	eth_proto = ntohs(et->et_protlen);
1077 
1078 	if (eth_proto < 1514) {
1079 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1080 		/*
1081 		 *	Got a 802.2 packet.  Check the other protocol field.
1082 		 *	XXX VLAN over 802.2+SNAP not implemented!
1083 		 */
1084 		eth_proto = ntohs(et802->et_prot);
1085 
1086 		ip = (struct ip_udp_hdr *)(in_packet + E802_HDR_SIZE);
1087 		len -= E802_HDR_SIZE;
1088 
1089 	} else if (eth_proto != PROT_VLAN) {	/* normal packet */
1090 		ip = (struct ip_udp_hdr *)(in_packet + ETHER_HDR_SIZE);
1091 		len -= ETHER_HDR_SIZE;
1092 
1093 	} else {			/* VLAN packet */
1094 		struct vlan_ethernet_hdr *vet =
1095 			(struct vlan_ethernet_hdr *)et;
1096 
1097 		debug_cond(DEBUG_NET_PKT, "VLAN packet received\n");
1098 
1099 		/* too small packet? */
1100 		if (len < VLAN_ETHER_HDR_SIZE)
1101 			return;
1102 
1103 		/* if no VLAN active */
1104 		if ((ntohs(net_our_vlan) & VLAN_IDMASK) == VLAN_NONE
1105 #if defined(CONFIG_CMD_CDP)
1106 				&& iscdp == 0
1107 #endif
1108 				)
1109 			return;
1110 
1111 		cti = ntohs(vet->vet_tag);
1112 		vlanid = cti & VLAN_IDMASK;
1113 		eth_proto = ntohs(vet->vet_type);
1114 
1115 		ip = (struct ip_udp_hdr *)(in_packet + VLAN_ETHER_HDR_SIZE);
1116 		len -= VLAN_ETHER_HDR_SIZE;
1117 	}
1118 
1119 	debug_cond(DEBUG_NET_PKT, "Receive from protocol 0x%x\n", eth_proto);
1120 
1121 #if defined(CONFIG_CMD_CDP)
1122 	if (iscdp) {
1123 		cdp_receive((uchar *)ip, len);
1124 		return;
1125 	}
1126 #endif
1127 
1128 	if ((myvlanid & VLAN_IDMASK) != VLAN_NONE) {
1129 		if (vlanid == VLAN_NONE)
1130 			vlanid = (mynvlanid & VLAN_IDMASK);
1131 		/* not matched? */
1132 		if (vlanid != (myvlanid & VLAN_IDMASK))
1133 			return;
1134 	}
1135 
1136 	switch (eth_proto) {
1137 	case PROT_ARP:
1138 		arp_receive(et, ip, len);
1139 		break;
1140 
1141 #ifdef CONFIG_CMD_RARP
1142 	case PROT_RARP:
1143 		rarp_receive(ip, len);
1144 		break;
1145 #endif
1146 	case PROT_IP:
1147 		debug_cond(DEBUG_NET_PKT, "Got IP\n");
1148 		/* Before we start poking the header, make sure it is there */
1149 		if (len < IP_UDP_HDR_SIZE) {
1150 			debug("len bad %d < %lu\n", len,
1151 			      (ulong)IP_UDP_HDR_SIZE);
1152 			return;
1153 		}
1154 		/* Check the packet length */
1155 		if (len < ntohs(ip->ip_len)) {
1156 			debug("len bad %d < %d\n", len, ntohs(ip->ip_len));
1157 			return;
1158 		}
1159 		len = ntohs(ip->ip_len);
1160 		debug_cond(DEBUG_NET_PKT, "len=%d, v=%02x\n",
1161 			   len, ip->ip_hl_v & 0xff);
1162 
1163 		/* Can't deal with anything except IPv4 */
1164 		if ((ip->ip_hl_v & 0xf0) != 0x40)
1165 			return;
1166 		/* Can't deal with IP options (headers != 20 bytes) */
1167 		if ((ip->ip_hl_v & 0x0f) > 0x05)
1168 			return;
1169 		/* Check the Checksum of the header */
1170 		if (!ip_checksum_ok((uchar *)ip, IP_HDR_SIZE)) {
1171 			debug("checksum bad\n");
1172 			return;
1173 		}
1174 		/* If it is not for us, ignore it */
1175 		dst_ip = net_read_ip(&ip->ip_dst);
1176 		if (net_ip.s_addr && dst_ip.s_addr != net_ip.s_addr &&
1177 		    dst_ip.s_addr != 0xFFFFFFFF) {
1178 #ifdef CONFIG_MCAST_TFTP
1179 			if (net_mcast_addr != dst_ip)
1180 #endif
1181 				return;
1182 		}
1183 		/* Read source IP address for later use */
1184 		src_ip = net_read_ip(&ip->ip_src);
1185 		/*
1186 		 * The function returns the unchanged packet if it's not
1187 		 * a fragment, and either the complete packet or NULL if
1188 		 * it is a fragment (if !CONFIG_IP_DEFRAG, it returns NULL)
1189 		 */
1190 		ip = net_defragment(ip, &len);
1191 		if (!ip)
1192 			return;
1193 		/*
1194 		 * watch for ICMP host redirects
1195 		 *
1196 		 * There is no real handler code (yet). We just watch
1197 		 * for ICMP host redirect messages. In case anybody
1198 		 * sees these messages: please contact me
1199 		 * (wd@denx.de), or - even better - send me the
1200 		 * necessary fixes :-)
1201 		 *
1202 		 * Note: in all cases where I have seen this so far
1203 		 * it was a problem with the router configuration,
1204 		 * for instance when a router was configured in the
1205 		 * BOOTP reply, but the TFTP server was on the same
1206 		 * subnet. So this is probably a warning that your
1207 		 * configuration might be wrong. But I'm not really
1208 		 * sure if there aren't any other situations.
1209 		 *
1210 		 * Simon Glass <sjg@chromium.org>: We get an ICMP when
1211 		 * we send a tftp packet to a dead connection, or when
1212 		 * there is no server at the other end.
1213 		 */
1214 		if (ip->ip_p == IPPROTO_ICMP) {
1215 			receive_icmp(ip, len, src_ip, et);
1216 			return;
1217 		} else if (ip->ip_p != IPPROTO_UDP) {	/* Only UDP packets */
1218 			return;
1219 		}
1220 
1221 		debug_cond(DEBUG_DEV_PKT,
1222 			   "received UDP (to=%pI4, from=%pI4, len=%d)\n",
1223 			   &dst_ip, &src_ip, len);
1224 
1225 #ifdef CONFIG_UDP_CHECKSUM
1226 		if (ip->udp_xsum != 0) {
1227 			ulong   xsum;
1228 			ushort *sumptr;
1229 			ushort  sumlen;
1230 
1231 			xsum  = ip->ip_p;
1232 			xsum += (ntohs(ip->udp_len));
1233 			xsum += (ntohl(ip->ip_src.s_addr) >> 16) & 0x0000ffff;
1234 			xsum += (ntohl(ip->ip_src.s_addr) >>  0) & 0x0000ffff;
1235 			xsum += (ntohl(ip->ip_dst.s_addr) >> 16) & 0x0000ffff;
1236 			xsum += (ntohl(ip->ip_dst.s_addr) >>  0) & 0x0000ffff;
1237 
1238 			sumlen = ntohs(ip->udp_len);
1239 			sumptr = (ushort *)&(ip->udp_src);
1240 
1241 			while (sumlen > 1) {
1242 				ushort sumdata;
1243 
1244 				sumdata = *sumptr++;
1245 				xsum += ntohs(sumdata);
1246 				sumlen -= 2;
1247 			}
1248 			if (sumlen > 0) {
1249 				ushort sumdata;
1250 
1251 				sumdata = *(unsigned char *)sumptr;
1252 				sumdata = (sumdata << 8) & 0xff00;
1253 				xsum += sumdata;
1254 			}
1255 			while ((xsum >> 16) != 0) {
1256 				xsum = (xsum & 0x0000ffff) +
1257 				       ((xsum >> 16) & 0x0000ffff);
1258 			}
1259 			if ((xsum != 0x00000000) && (xsum != 0x0000ffff)) {
1260 				printf(" UDP wrong checksum %08lx %08x\n",
1261 				       xsum, ntohs(ip->udp_xsum));
1262 				return;
1263 			}
1264 		}
1265 #endif
1266 
1267 #if defined(CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
1268 		nc_input_packet((uchar *)ip + IP_UDP_HDR_SIZE,
1269 				src_ip,
1270 				ntohs(ip->udp_dst),
1271 				ntohs(ip->udp_src),
1272 				ntohs(ip->udp_len) - UDP_HDR_SIZE);
1273 #endif
1274 		/*
1275 		 * IP header OK.  Pass the packet to the current handler.
1276 		 */
1277 		(*udp_packet_handler)((uchar *)ip + IP_UDP_HDR_SIZE,
1278 				      ntohs(ip->udp_dst),
1279 				      src_ip,
1280 				      ntohs(ip->udp_src),
1281 				      ntohs(ip->udp_len) - UDP_HDR_SIZE);
1282 		break;
1283 	}
1284 }
1285 
1286 /**********************************************************************/
1287 
1288 static int net_check_prereq(enum proto_t protocol)
1289 {
1290 	switch (protocol) {
1291 		/* Fall through */
1292 #if defined(CONFIG_CMD_PING)
1293 	case PING:
1294 		if (net_ping_ip.s_addr == 0) {
1295 			puts("*** ERROR: ping address not given\n");
1296 			return 1;
1297 		}
1298 		goto common;
1299 #endif
1300 #if defined(CONFIG_CMD_SNTP)
1301 	case SNTP:
1302 		if (net_ntp_server.s_addr == 0) {
1303 			puts("*** ERROR: NTP server address not given\n");
1304 			return 1;
1305 		}
1306 		goto common;
1307 #endif
1308 #if defined(CONFIG_CMD_DNS)
1309 	case DNS:
1310 		if (net_dns_server.s_addr == 0) {
1311 			puts("*** ERROR: DNS server address not given\n");
1312 			return 1;
1313 		}
1314 		goto common;
1315 #endif
1316 #if defined(CONFIG_CMD_NFS)
1317 	case NFS:
1318 #endif
1319 		/* Fall through */
1320 	case TFTPGET:
1321 	case TFTPPUT:
1322 		if (net_server_ip.s_addr == 0) {
1323 			puts("*** ERROR: `serverip' not set\n");
1324 			return 1;
1325 		}
1326 #if	defined(CONFIG_CMD_PING) || defined(CONFIG_CMD_SNTP) || \
1327 	defined(CONFIG_CMD_DNS)
1328 common:
1329 #endif
1330 		/* Fall through */
1331 
1332 	case NETCONS:
1333 	case TFTPSRV:
1334 		if (net_ip.s_addr == 0) {
1335 			puts("*** ERROR: `ipaddr' not set\n");
1336 			return 1;
1337 		}
1338 		/* Fall through */
1339 
1340 #ifdef CONFIG_CMD_RARP
1341 	case RARP:
1342 #endif
1343 	case BOOTP:
1344 	case CDP:
1345 	case DHCP:
1346 	case LINKLOCAL:
1347 		if (memcmp(net_ethaddr, "\0\0\0\0\0\0", 6) == 0) {
1348 			int num = eth_get_dev_index();
1349 
1350 			switch (num) {
1351 			case -1:
1352 				puts("*** ERROR: No ethernet found.\n");
1353 				return 1;
1354 			case 0:
1355 				puts("*** ERROR: `ethaddr' not set\n");
1356 				break;
1357 			default:
1358 				printf("*** ERROR: `eth%daddr' not set\n",
1359 				       num);
1360 				break;
1361 			}
1362 
1363 			net_start_again();
1364 			return 2;
1365 		}
1366 		/* Fall through */
1367 	default:
1368 		return 0;
1369 	}
1370 	return 0;		/* OK */
1371 }
1372 /**********************************************************************/
1373 
1374 int
1375 net_eth_hdr_size(void)
1376 {
1377 	ushort myvlanid;
1378 
1379 	myvlanid = ntohs(net_our_vlan);
1380 	if (myvlanid == (ushort)-1)
1381 		myvlanid = VLAN_NONE;
1382 
1383 	return ((myvlanid & VLAN_IDMASK) == VLAN_NONE) ? ETHER_HDR_SIZE :
1384 		VLAN_ETHER_HDR_SIZE;
1385 }
1386 
1387 int net_set_ether(uchar *xet, const uchar *dest_ethaddr, uint prot)
1388 {
1389 	struct ethernet_hdr *et = (struct ethernet_hdr *)xet;
1390 	ushort myvlanid;
1391 
1392 	myvlanid = ntohs(net_our_vlan);
1393 	if (myvlanid == (ushort)-1)
1394 		myvlanid = VLAN_NONE;
1395 
1396 	memcpy(et->et_dest, dest_ethaddr, 6);
1397 	memcpy(et->et_src, net_ethaddr, 6);
1398 	if ((myvlanid & VLAN_IDMASK) == VLAN_NONE) {
1399 		et->et_protlen = htons(prot);
1400 		return ETHER_HDR_SIZE;
1401 	} else {
1402 		struct vlan_ethernet_hdr *vet =
1403 			(struct vlan_ethernet_hdr *)xet;
1404 
1405 		vet->vet_vlan_type = htons(PROT_VLAN);
1406 		vet->vet_tag = htons((0 << 5) | (myvlanid & VLAN_IDMASK));
1407 		vet->vet_type = htons(prot);
1408 		return VLAN_ETHER_HDR_SIZE;
1409 	}
1410 }
1411 
1412 int net_update_ether(struct ethernet_hdr *et, uchar *addr, uint prot)
1413 {
1414 	ushort protlen;
1415 
1416 	memcpy(et->et_dest, addr, 6);
1417 	memcpy(et->et_src, net_ethaddr, 6);
1418 	protlen = ntohs(et->et_protlen);
1419 	if (protlen == PROT_VLAN) {
1420 		struct vlan_ethernet_hdr *vet =
1421 			(struct vlan_ethernet_hdr *)et;
1422 		vet->vet_type = htons(prot);
1423 		return VLAN_ETHER_HDR_SIZE;
1424 	} else if (protlen > 1514) {
1425 		et->et_protlen = htons(prot);
1426 		return ETHER_HDR_SIZE;
1427 	} else {
1428 		/* 802.2 + SNAP */
1429 		struct e802_hdr *et802 = (struct e802_hdr *)et;
1430 		et802->et_prot = htons(prot);
1431 		return E802_HDR_SIZE;
1432 	}
1433 }
1434 
1435 void net_set_ip_header(uchar *pkt, struct in_addr dest, struct in_addr source)
1436 {
1437 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1438 
1439 	/*
1440 	 *	Construct an IP header.
1441 	 */
1442 	/* IP_HDR_SIZE / 4 (not including UDP) */
1443 	ip->ip_hl_v  = 0x45;
1444 	ip->ip_tos   = 0;
1445 	ip->ip_len   = htons(IP_HDR_SIZE);
1446 	ip->ip_id    = htons(net_ip_id++);
1447 	ip->ip_off   = htons(IP_FLAGS_DFRAG);	/* Don't fragment */
1448 	ip->ip_ttl   = 255;
1449 	ip->ip_sum   = 0;
1450 	/* already in network byte order */
1451 	net_copy_ip((void *)&ip->ip_src, &source);
1452 	/* already in network byte order */
1453 	net_copy_ip((void *)&ip->ip_dst, &dest);
1454 }
1455 
1456 void net_set_udp_header(uchar *pkt, struct in_addr dest, int dport, int sport,
1457 			int len)
1458 {
1459 	struct ip_udp_hdr *ip = (struct ip_udp_hdr *)pkt;
1460 
1461 	/*
1462 	 *	If the data is an odd number of bytes, zero the
1463 	 *	byte after the last byte so that the checksum
1464 	 *	will work.
1465 	 */
1466 	if (len & 1)
1467 		pkt[IP_UDP_HDR_SIZE + len] = 0;
1468 
1469 	net_set_ip_header(pkt, dest, net_ip);
1470 	ip->ip_len   = htons(IP_UDP_HDR_SIZE + len);
1471 	ip->ip_p     = IPPROTO_UDP;
1472 	ip->ip_sum   = compute_ip_checksum(ip, IP_HDR_SIZE);
1473 
1474 	ip->udp_src  = htons(sport);
1475 	ip->udp_dst  = htons(dport);
1476 	ip->udp_len  = htons(UDP_HDR_SIZE + len);
1477 	ip->udp_xsum = 0;
1478 }
1479 
1480 void copy_filename(char *dst, const char *src, int size)
1481 {
1482 	if (*src && (*src == '"')) {
1483 		++src;
1484 		--size;
1485 	}
1486 
1487 	while ((--size > 0) && *src && (*src != '"'))
1488 		*dst++ = *src++;
1489 	*dst = '\0';
1490 }
1491 
1492 #if	defined(CONFIG_CMD_NFS)		|| \
1493 	defined(CONFIG_CMD_SNTP)	|| \
1494 	defined(CONFIG_CMD_DNS)
1495 /*
1496  * make port a little random (1024-17407)
1497  * This keeps the math somewhat trivial to compute, and seems to work with
1498  * all supported protocols/clients/servers
1499  */
1500 unsigned int random_port(void)
1501 {
1502 	return 1024 + (get_timer(0) % 0x4000);
1503 }
1504 #endif
1505 
1506 void ip_to_string(struct in_addr x, char *s)
1507 {
1508 	x.s_addr = ntohl(x.s_addr);
1509 	sprintf(s, "%d.%d.%d.%d",
1510 		(int) ((x.s_addr >> 24) & 0xff),
1511 		(int) ((x.s_addr >> 16) & 0xff),
1512 		(int) ((x.s_addr >> 8) & 0xff),
1513 		(int) ((x.s_addr >> 0) & 0xff)
1514 	);
1515 }
1516 
1517 void vlan_to_string(ushort x, char *s)
1518 {
1519 	x = ntohs(x);
1520 
1521 	if (x == (ushort)-1)
1522 		x = VLAN_NONE;
1523 
1524 	if (x == VLAN_NONE)
1525 		strcpy(s, "none");
1526 	else
1527 		sprintf(s, "%d", x & VLAN_IDMASK);
1528 }
1529 
1530 ushort string_to_vlan(const char *s)
1531 {
1532 	ushort id;
1533 
1534 	if (s == NULL)
1535 		return htons(VLAN_NONE);
1536 
1537 	if (*s < '0' || *s > '9')
1538 		id = VLAN_NONE;
1539 	else
1540 		id = (ushort)simple_strtoul(s, NULL, 10);
1541 
1542 	return htons(id);
1543 }
1544 
1545 ushort getenv_vlan(char *var)
1546 {
1547 	return string_to_vlan(getenv(var));
1548 }
1549