xref: /openbmc/u-boot/net/wol.c (revision cbd2fba1)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2018 Lothar Felten, lothar.felten@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