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      1 // SPDX-License-Identifier: GPL-2.0+
      2 /*
      3  * Copyright 2018 Lothar Felten, lothar.felten (at) gmail.com
      4  */
      5 
      6 #include <common.h>
      7 #include <command.h>
      8 #include <net.h>
      9 #include <environment.h>
     10 #include "wol.h"
     11 
     12 static ulong wol_timeout = WOL_DEFAULT_TIMEOUT;
     13 
     14 /*
     15  * Check incoming Wake-on-LAN packet for:
     16  * - sync bytes
     17  * - sixteen copies of the target MAC address
     18  *
     19  * @param wol Wake-on-LAN packet
     20  * @param len Packet length
     21  */
     22 static int wol_check_magic(struct wol_hdr *wol, unsigned int len)
     23 {
     24 	int i;
     25 
     26 	if (len < sizeof(struct wol_hdr))
     27 		return 0;
     28 
     29 	for (i = 0; i < WOL_SYNC_COUNT; i++)
     30 		if (wol->wol_sync[i] != WOL_SYNC_BYTE)
     31 			return 0;
     32 
     33 	for (i = 0; i < WOL_MAC_REPETITIONS; i++)
     34 		if (memcmp(&wol->wol_dest[i * ARP_HLEN],
     35 			   net_ethaddr, ARP_HLEN) != 0)
     36 			return 0;
     37 
     38 	return 1;
     39 }
     40 
     41 void wol_receive(struct ip_udp_hdr *ip, unsigned int len)
     42 {
     43 	struct wol_hdr *wol;
     44 
     45 	wol = (struct wol_hdr *)ip;
     46 
     47 	if (!wol_check_magic(wol, len))
     48 		return;
     49 
     50 	/* save the optional password using the ether-wake formats */
     51 	/* don't check for exact length, the packet might have padding */
     52 	if (len >= (sizeof(struct wol_hdr) + WOL_PASSWORD_6B)) {
     53 		eth_env_set_enetaddr("wolpassword", wol->wol_passwd);
     54 	} else if (len >= (sizeof(struct wol_hdr) + WOL_PASSWORD_4B)) {
     55 		char buffer[16];
     56 		struct in_addr *ip = (struct in_addr *)(wol->wol_passwd);
     57 
     58 		ip_to_string(*ip, buffer);
     59 		env_set("wolpassword", buffer);
     60 	}
     61 	net_set_state(NETLOOP_SUCCESS);
     62 }
     63 
     64 static void wol_udp_handler(uchar *pkt, unsigned int dest, struct in_addr sip,
     65 			    unsigned int src, unsigned int len)
     66 {
     67 	struct wol_hdr *wol;
     68 
     69 	wol = (struct wol_hdr *)pkt;
     70 
     71 	/* UDP destination port must be 0, 7 or 9 */
     72 	if (dest != 0 && dest != 7 && dest != 9)
     73 		return;
     74 
     75 	if (!wol_check_magic(wol, len))
     76 		return;
     77 
     78 	net_set_state(NETLOOP_SUCCESS);
     79 }
     80 
     81 void wol_set_timeout(ulong timeout)
     82 {
     83 	wol_timeout = timeout;
     84 }
     85 
     86 static void wol_timeout_handler(void)
     87 {
     88 	eth_halt();
     89 	net_set_state(NETLOOP_FAIL);
     90 }
     91 
     92 void wol_start(void)
     93 {
     94 	net_set_timeout_handler(wol_timeout, wol_timeout_handler);
     95 	net_set_udp_handler(wol_udp_handler);
     96 }
     97