xref: /openbmc/u-boot/net/net.c (revision ca831f4933dc68d9ed1b6399cbda90068c520005)
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 <console.h>
87  #include <environment.h>
88  #include <errno.h>
89  #include <net.h>
90  #include <net/tftp.h>
91  #if defined(CONFIG_STATUS_LED)
92  #include <miiphy.h>
93  #include <status_led.h>
94  #endif
95  #include <watchdog.h>
96  #include <linux/compiler.h>
97  #include "arp.h"
98  #include "bootp.h"
99  #include "cdp.h"
100  #if defined(CONFIG_CMD_DNS)
101  #include "dns.h"
102  #endif
103  #include "link_local.h"
104  #include "nfs.h"
105  #include "ping.h"
106  #include "rarp.h"
107  #if defined(CONFIG_CMD_SNTP)
108  #include "sntp.h"
109  #endif
110  
111  DECLARE_GLOBAL_DATA_PTR;
112  
113  /** BOOTP EXTENTIONS **/
114  
115  /* Our subnet mask (0=unknown) */
116  struct in_addr net_netmask;
117  /* Our gateways IP address */
118  struct in_addr net_gateway;
119  /* Our DNS IP address */
120  struct in_addr net_dns_server;
121  #if defined(CONFIG_BOOTP_DNS2)
122  /* Our 2nd DNS IP address */
123  struct in_addr net_dns_server2;
124  #endif
125  
126  #ifdef CONFIG_MCAST_TFTP	/* Multicast TFTP */
127  struct in_addr net_mcast_addr;
128  #endif
129  
130  /** END OF BOOTP EXTENTIONS **/
131  
132  /* Our ethernet address */
133  u8 net_ethaddr[6];
134  /* Boot server enet address */
135  u8 net_server_ethaddr[6];
136  /* Our IP addr (0 = unknown) */
137  struct in_addr	net_ip;
138  /* Server IP addr (0 = unknown) */
139  struct in_addr	net_server_ip;
140  /* Current receive packet */
141  uchar *net_rx_packet;
142  /* Current rx packet length */
143  int		net_rx_packet_len;
144  /* IP packet ID */
145  static unsigned	net_ip_id;
146  /* Ethernet bcast address */
147  const u8 net_bcast_ethaddr[6] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff };
148  const u8 net_null_ethaddr[6];
149  #ifdef CONFIG_API
150  void (*push_packet)(void *, int len) = 0;
151  #endif
152  /* Network loop state */
153  enum net_loop_state net_state;
154  /* Tried all network devices */
155  int		net_restart_wrap;
156  /* Network loop restarted */
157  static int	net_restarted;
158  /* At least one device configured */
159  static int	net_dev_exists;
160  
161  /* XXX in both little & big endian machines 0xFFFF == ntohs(-1) */
162  /* default is without VLAN */
163  ushort		net_our_vlan = 0xFFFF;
164  /* ditto */
165  ushort		net_native_vlan = 0xFFFF;
166  
167  /* Boot File name */
168  char net_boot_file_name[1024];
169  /* The actual transferred size of the bootfile (in bytes) */
170  u32 net_boot_file_size;
171  /* Boot file size in blocks as reported by the DHCP server */
172  u32 net_boot_file_expected_size_in_blocks;
173  
174  #if defined(CONFIG_CMD_SNTP)
175  /* NTP server IP address */
176  struct in_addr	net_ntp_server;
177  /* offset time from UTC */
178  int		net_ntp_time_offset;
179  #endif
180  
181  static uchar net_pkt_buf[(PKTBUFSRX+1) * PKTSIZE_ALIGN + PKTALIGN];
182  /* Receive packets */
183  uchar *net_rx_packets[PKTBUFSRX];
184  /* Current UDP RX packet handler */
185  static rxhand_f *udp_packet_handler;
186  /* Current ARP RX packet handler */
187  static rxhand_f *arp_packet_handler;
188  #ifdef CONFIG_CMD_TFTPPUT
189  /* Current ICMP rx handler */
190  static rxhand_icmp_f *packet_icmp_handler;
191  #endif
192  /* Current timeout handler */
193  static thand_f *time_handler;
194  /* Time base value */
195  static ulong	time_start;
196  /* Current timeout value */
197  static ulong	time_delta;
198  /* THE transmit packet */
199  uchar *net_tx_packet;
200  
201  static int net_check_prereq(enum proto_t protocol);
202  
203  static int net_try_count;
204  
205  int __maybe_unused net_busy_flag;
206  
207  /**********************************************************************/
208  
209  static int on_bootfile(const char *name, const char *value, enum env_op op,
210  	int flags)
211  {
212  	if (flags & H_PROGRAMMATIC)
213  		return 0;
214  
215  	switch (op) {
216  	case env_op_create:
217  	case env_op_overwrite:
218  		copy_filename(net_boot_file_name, value,
219  			      sizeof(net_boot_file_name));
220  		break;
221  	default:
222  		break;
223  	}
224  
225  	return 0;
226  }
227  U_BOOT_ENV_CALLBACK(bootfile, on_bootfile);
228  
229  static int on_ipaddr(const char *name, const char *value, enum env_op op,
230  	int flags)
231  {
232  	if (flags & H_PROGRAMMATIC)
233  		return 0;
234  
235  	net_ip = string_to_ip(value);
236  
237  	return 0;
238  }
239  U_BOOT_ENV_CALLBACK(ipaddr, on_ipaddr);
240  
241  static int on_gatewayip(const char *name, const char *value, enum env_op op,
242  	int flags)
243  {
244  	if (flags & H_PROGRAMMATIC)
245  		return 0;
246  
247  	net_gateway = string_to_ip(value);
248  
249  	return 0;
250  }
251  U_BOOT_ENV_CALLBACK(gatewayip, on_gatewayip);
252  
253  static int on_netmask(const char *name, const char *value, enum env_op op,
254  	int flags)
255  {
256  	if (flags & H_PROGRAMMATIC)
257  		return 0;
258  
259  	net_netmask = string_to_ip(value);
260  
261  	return 0;
262  }
263  U_BOOT_ENV_CALLBACK(netmask, on_netmask);
264  
265  static int on_serverip(const char *name, const char *value, enum env_op op,
266  	int flags)
267  {
268  	if (flags & H_PROGRAMMATIC)
269  		return 0;
270  
271  	net_server_ip = string_to_ip(value);
272  
273  	return 0;
274  }
275  U_BOOT_ENV_CALLBACK(serverip, on_serverip);
276  
277  static int on_nvlan(const char *name, const char *value, enum env_op op,
278  	int flags)
279  {
280  	if (flags & H_PROGRAMMATIC)
281  		return 0;
282  
283  	net_native_vlan = string_to_vlan(value);
284  
285  	return 0;
286  }
287  U_BOOT_ENV_CALLBACK(nvlan, on_nvlan);
288  
289  static int on_vlan(const char *name, const char *value, enum env_op op,
290  	int flags)
291  {
292  	if (flags & H_PROGRAMMATIC)
293  		return 0;
294  
295  	net_our_vlan = string_to_vlan(value);
296  
297  	return 0;
298  }
299  U_BOOT_ENV_CALLBACK(vlan, on_vlan);
300  
301  #if defined(CONFIG_CMD_DNS)
302  static int on_dnsip(const char *name, const char *value, enum env_op op,
303  	int flags)
304  {
305  	if (flags & H_PROGRAMMATIC)
306  		return 0;
307  
308  	net_dns_server = string_to_ip(value);
309  
310  	return 0;
311  }
312  U_BOOT_ENV_CALLBACK(dnsip, on_dnsip);
313  #endif
314  
315  /*
316   * Check if autoload is enabled. If so, use either NFS or TFTP to download
317   * the boot file.
318   */
319  void net_auto_load(void)
320  {
321  #if defined(CONFIG_CMD_NFS)
322  	const char *s = getenv("autoload");
323  
324  	if (s != NULL && strcmp(s, "NFS") == 0) {
325  		/*
326  		 * Use NFS to load the bootfile.
327  		 */
328  		nfs_start();
329  		return;
330  	}
331  #endif
332  	if (getenv_yesno("autoload") == 0) {
333  		/*
334  		 * Just use BOOTP/RARP to configure system;
335  		 * Do not use TFTP to load the bootfile.
336  		 */
337  		net_set_state(NETLOOP_SUCCESS);
338  		return;
339  	}
340  	tftp_start(TFTPGET);
341  }
342  
343  static void net_init_loop(void)
344  {
345  	if (eth_get_dev())
346  		memcpy(net_ethaddr, eth_get_ethaddr(), 6);
347  
348  	return;
349  }
350  
351  static void net_clear_handlers(void)
352  {
353  	net_set_udp_handler(NULL);
354  	net_set_arp_handler(NULL);
355  	net_set_timeout_handler(0, NULL);
356  }
357  
358  static void net_cleanup_loop(void)
359  {
360  	net_clear_handlers();
361  }
362  
363  void net_init(void)
364  {
365  	static int first_call = 1;
366  
367  	if (first_call) {
368  		/*
369  		 *	Setup packet buffers, aligned correctly.
370  		 */
371  		int i;
372  
373  		net_tx_packet = &net_pkt_buf[0] + (PKTALIGN - 1);
374  		net_tx_packet -= (ulong)net_tx_packet % PKTALIGN;
375  		for (i = 0; i < PKTBUFSRX; i++) {
376  			net_rx_packets[i] = net_tx_packet +
377  				(i + 1) * PKTSIZE_ALIGN;
378  		}
379  		arp_init();
380  		net_clear_handlers();
381  
382  		/* Only need to setup buffer pointers once. */
383  		first_call = 0;
384  	}
385  
386  	net_init_loop();
387  }
388  
389  /**********************************************************************/
390  /*
391   *	Main network processing loop.
392   */
393  
394  int net_loop(enum proto_t protocol)
395  {
396  	int ret = -EINVAL;
397  
398  	net_restarted = 0;
399  	net_dev_exists = 0;
400  	net_try_count = 1;
401  	debug_cond(DEBUG_INT_STATE, "--- net_loop Entry\n");
402  
403  	bootstage_mark_name(BOOTSTAGE_ID_ETH_START, "eth_start");
404  	net_init();
405  	if (eth_is_on_demand_init() || protocol != NETCONS) {
406  		eth_halt();
407  		eth_set_current();
408  		ret = eth_init();
409  		if (ret < 0) {
410  			eth_halt();
411  			return ret;
412  		}
413  	} else {
414  		eth_init_state_only();
415  	}
416  restart:
417  #ifdef CONFIG_USB_KEYBOARD
418  	net_busy_flag = 0;
419  #endif
420  	net_set_state(NETLOOP_CONTINUE);
421  
422  	/*
423  	 *	Start the ball rolling with the given start function.  From
424  	 *	here on, this code is a state machine driven by received
425  	 *	packets and timer events.
426  	 */
427  	debug_cond(DEBUG_INT_STATE, "--- net_loop Init\n");
428  	net_init_loop();
429  
430  	switch (net_check_prereq(protocol)) {
431  	case 1:
432  		/* network not configured */
433  		eth_halt();
434  		return -ENODEV;
435  
436  	case 2:
437  		/* network device not configured */
438  		break;
439  
440  	case 0:
441  		net_dev_exists = 1;
442  		net_boot_file_size = 0;
443  		switch (protocol) {
444  		case TFTPGET:
445  #ifdef CONFIG_CMD_TFTPPUT
446  		case TFTPPUT:
447  #endif
448  			/* always use ARP to get server ethernet address */
449  			tftp_start(protocol);
450  			break;
451  #ifdef CONFIG_CMD_TFTPSRV
452  		case TFTPSRV:
453  			tftp_start_server();
454  			break;
455  #endif
456  #if defined(CONFIG_CMD_DHCP)
457  		case DHCP:
458  			bootp_reset();
459  			net_ip.s_addr = 0;
460  			dhcp_request();		/* Basically same as BOOTP */
461  			break;
462  #endif
463  
464  		case BOOTP:
465  			bootp_reset();
466  			net_ip.s_addr = 0;
467  			bootp_request();
468  			break;
469  
470  #if defined(CONFIG_CMD_RARP)
471  		case RARP:
472  			rarp_try = 0;
473  			net_ip.s_addr = 0;
474  			rarp_request();
475  			break;
476  #endif
477  #if defined(CONFIG_CMD_PING)
478  		case PING:
479  			ping_start();
480  			break;
481  #endif
482  #if defined(CONFIG_CMD_NFS)
483  		case NFS:
484  			nfs_start();
485  			break;
486  #endif
487  #if defined(CONFIG_CMD_CDP)
488  		case CDP:
489  			cdp_start();
490  			break;
491  #endif
492  #if defined(CONFIG_NETCONSOLE) && !(CONFIG_SPL_BUILD)
493  		case NETCONS:
494  			nc_start();
495  			break;
496  #endif
497  #if defined(CONFIG_CMD_SNTP)
498  		case SNTP:
499  			sntp_start();
500  			break;
501  #endif
502  #if defined(CONFIG_CMD_DNS)
503  		case DNS:
504  			dns_start();
505  			break;
506  #endif
507  #if defined(CONFIG_CMD_LINK_LOCAL)
508  		case LINKLOCAL:
509  			link_local_start();
510  			break;
511  #endif
512  		default:
513  			break;
514  		}
515  
516  		break;
517  	}
518  
519  #if defined(CONFIG_MII) || defined(CONFIG_CMD_MII)
520  #if	defined(CONFIG_SYS_FAULT_ECHO_LINK_DOWN)	&& \
521  	defined(CONFIG_STATUS_LED)			&& \
522  	defined(STATUS_LED_RED)
523  	/*
524  	 * Echo the inverted link state to the fault LED.
525  	 */
526  	if (miiphy_link(eth_get_dev()->name, CONFIG_SYS_FAULT_MII_ADDR))
527  		status_led_set(STATUS_LED_RED, STATUS_LED_OFF);
528  	else
529  		status_led_set(STATUS_LED_RED, STATUS_LED_ON);
530  #endif /* CONFIG_SYS_FAULT_ECHO_LINK_DOWN, ... */
531  #endif /* CONFIG_MII, ... */
532  #ifdef CONFIG_USB_KEYBOARD
533  	net_busy_flag = 1;
534  #endif
535  
536  	/*
537  	 *	Main packet reception loop.  Loop receiving packets until
538  	 *	someone sets `net_state' to a state that terminates.
539  	 */
540  	for (;;) {
541  		WATCHDOG_RESET();
542  #ifdef CONFIG_SHOW_ACTIVITY
543  		show_activity(1);
544  #endif
545  		if (arp_timeout_check() > 0)
546  			time_start = get_timer(0);
547  
548  		/*
549  		 *	Check the ethernet for a new packet.  The ethernet
550  		 *	receive routine will process it.
551  		 *	Most drivers return the most recent packet size, but not
552  		 *	errors that may have happened.
553  		 */
554  		eth_rx();
555  
556  		/*
557  		 *	Abort if ctrl-c was pressed.
558  		 */
559  		if (ctrlc()) {
560  			/* cancel any ARP that may not have completed */
561  			net_arp_wait_packet_ip.s_addr = 0;
562  
563  			net_cleanup_loop();
564  			eth_halt();
565  			/* Invalidate the last protocol */
566  			eth_set_last_protocol(BOOTP);
567  
568  			puts("\nAbort\n");
569  			/* include a debug print as well incase the debug
570  			   messages are directed to stderr */
571  			debug_cond(DEBUG_INT_STATE, "--- net_loop Abort!\n");
572  			ret = -EINTR;
573  			goto done;
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