1 /* vi: set sw=4 ts=4: */
3 * ether-wake.c - Send a magic packet to wake up sleeping machines.
5 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
7 * Author: Donald Becker, http://www.scyld.com/"; http://www.scyld.com/wakeonlan.html
8 * Busybox port: Christian Volkmann <haveaniceday@online.de>
9 * Used version of ether-wake.c: v1.09 11/12/2003 Donald Becker, http://www.scyld.com/";
12 /* full usage according Donald Becker
13 * usage: ether-wake [-i <ifname>] [-p aa:bb:cc:dd[:ee:ff]] 00:11:22:33:44:55\n"
15 * This program generates and transmits a Wake-On-LAN (WOL)\n"
16 * \"Magic Packet\", used for restarting machines that have been\n"
17 * soft-powered-down (ACPI D3-warm state).\n"
18 * It currently generates the standard AMD Magic Packet format, with\n"
19 * an optional password appended.\n"
21 * The single required parameter is the Ethernet MAC (station) address\n"
22 * of the machine to wake or a host ID with known NSS 'ethers' entry.\n"
23 * The MAC address may be found with the 'arp' program while the target\n"
24 * machine is awake.\n"
27 * -b Send wake-up packet to the broadcast address.\n"
28 * -D Increase the debug level.\n"
29 * -i ifname Use interface IFNAME instead of the default 'eth0'.\n"
30 * -p <pw> Append the four or six byte password PW to the packet.\n"
31 * A password is only required for a few adapter types.\n"
32 * The password may be specified in ethernet hex format\n"
33 * or dotted decimal (Internet address)\n"
34 * -p 00:22:44:66:88:aa\n"
38 * This program generates and transmits a Wake-On-LAN (WOL) "Magic Packet",
39 * used for restarting machines that have been soft-powered-down
40 * (ACPI D3-warm state). It currently generates the standard AMD Magic Packet
41 * format, with an optional password appended.
43 * This software may be used and distributed according to the terms
44 * of the GNU Public License, incorporated herein by reference.
45 * Contact the author for use under other terms.
47 * This source file was originally part of the network tricks package, and
48 * is now distributed to support the Scyld Beowulf system.
49 * Copyright 1999-2003 Donald Becker and Scyld Computing Corporation.
51 * The author may be reached as becker@scyld, or C/O
52 * Scyld Computing Corporation
53 * 914 Bay Ridge Road, Suite 220
57 * On some systems dropping root capability allows the process to be
58 * dumped, traced or debugged.
59 * If someone traces this program, they get control of a raw socket.
60 * Linux handles this safely, but beware when porting this program.
62 * An alternative to needing 'root' is using a UDP broadcast socket, however
63 * doing so only works with adapters configured for unicast+broadcast Rx
64 * filter. That configuration consumes more power.
68 #include <netpacket/packet.h>
69 #include <net/ethernet.h>
70 #include <netinet/ether.h>
75 /* Note: PF_INET, SOCK_DGRAM, IPPROTO_UDP would allow SIOCGIFHWADDR to
76 * work as non-root, but we need SOCK_PACKET to specify the Ethernet
77 * destination address.
80 # define whereto_t sockaddr_ll
81 # define make_socket() xsocket(PF_PACKET, SOCK_RAW, 0)
83 # define whereto_t sockaddr
84 # define make_socket() xsocket(AF_INET, SOCK_PACKET, SOCK_PACKET)
88 # define bb_debug_msg(fmt, args...) fprintf(stderr, fmt, ## args)
89 void bb_debug_dump_packet(unsigned char *outpack
, int pktsize
)
92 printf("packet dump:\n");
93 for (i
= 0; i
< pktsize
; ++i
) {
94 printf("%2.2x ", outpack
[i
]);
95 if (i
% 20 == 19) bb_putchar('\n');
100 # define bb_debug_msg(fmt, args...) ((void)0)
101 # define bb_debug_dump_packet(outpack, pktsize) ((void)0)
104 /* Convert the host ID string to a MAC address.
105 * The string may be a:
110 static void get_dest_addr(const char *hostid
, struct ether_addr
*eaddr
)
112 struct ether_addr
*eap
;
114 eap
= ether_aton(hostid
);
117 bb_debug_msg("The target station address is %s\n\n", ether_ntoa(eaddr
));
118 #if !defined(__UCLIBC__)
119 } else if (ether_hostton(hostid
, eaddr
) == 0) {
120 bb_debug_msg("Station address for hostname %s is %s\n\n", hostid
, ether_ntoa(eaddr
));
126 static int get_fill(unsigned char *pkt
, struct ether_addr
*eaddr
, int broadcast
)
129 unsigned char *station_addr
= eaddr
->ether_addr_octet
;
131 memset(pkt
, 0xff, 6);
133 memcpy(pkt
, station_addr
, 6);
136 memcpy(pkt
, station_addr
, 6); /* 6 */
139 *pkt
++ = 0x08; /* 12 */ /* Or 0x0806 for ARP, 0x8035 for RARP */
140 *pkt
++ = 0x42; /* 13 */
142 memset(pkt
, 0xff, 6); /* 14 */
144 for (i
= 0; i
< 16; ++i
) {
146 memcpy(pkt
, station_addr
, 6); /* 20,26,32,... */
149 return 20 + 16*6; /* length of packet */
152 static int get_wol_pw(const char *ethoptarg
, unsigned char *wol_passwd
)
157 /* handle MAC format */
158 byte_cnt
= sscanf(ethoptarg
, "%2x:%2x:%2x:%2x:%2x:%2x",
159 &passwd
[0], &passwd
[1], &passwd
[2],
160 &passwd
[3], &passwd
[4], &passwd
[5]);
161 /* handle IP format */
162 // FIXME: why < 4?? should it be < 6?
164 byte_cnt
= sscanf(ethoptarg
, "%u.%u.%u.%u",
165 &passwd
[0], &passwd
[1], &passwd
[2], &passwd
[3]);
167 bb_error_msg("cannot read Wake-On-LAN pass");
170 // TODO: check invalid numbers >255??
171 for (i
= 0; i
< byte_cnt
; ++i
)
172 wol_passwd
[i
] = passwd
[i
];
174 bb_debug_msg("password: %2.2x %2.2x %2.2x %2.2x (%d)\n\n",
175 wol_passwd
[0], wol_passwd
[1], wol_passwd
[2], wol_passwd
[3],
181 int ether_wake_main(int argc
, char **argv
) MAIN_EXTERNALLY_VISIBLE
;
182 int ether_wake_main(int argc UNUSED_PARAM
, char **argv
)
184 const char *ifname
= "eth0";
187 unsigned char wol_passwd
[6];
188 int wol_passwd_sz
= 0;
189 int s
; /* Raw socket */
191 unsigned char outpack
[1000];
193 struct ether_addr eaddr
;
194 struct whereto_t whereto
; /* who to wake up */
196 /* handle misc user options */
197 opt_complementary
= "=1";
198 flags
= getopt32(argv
, "bi:p:", &ifname
, &pass
);
199 if (flags
& 4) /* -p */
200 wol_passwd_sz
= get_wol_pw(pass
, wol_passwd
);
201 flags
&= 1; /* we further interested only in -b [bcast] flag */
203 /* create the raw socket */
206 /* now that we have a raw socket we can drop root */
207 /* xsetuid(getuid()); - but save on code size... */
209 /* look up the dest mac address */
210 get_dest_addr(argv
[optind
], &eaddr
);
212 /* fill out the header of the packet */
213 pktsize
= get_fill(outpack
, &eaddr
, flags
/* & 1 OPT_BROADCAST */);
215 bb_debug_dump_packet(outpack
, pktsize
);
217 /* Fill in the source address, if possible. */
220 struct ifreq if_hwaddr
;
222 strncpy_IFNAMSIZ(if_hwaddr
.ifr_name
, ifname
);
223 ioctl_or_perror_and_die(s
, SIOCGIFHWADDR
, &if_hwaddr
, "SIOCGIFHWADDR on %s failed", ifname
);
225 memcpy(outpack
+6, if_hwaddr
.ifr_hwaddr
.sa_data
, 6);
229 unsigned char *hwaddr
= if_hwaddr
.ifr_hwaddr
.sa_data
;
230 printf("The hardware address (SIOCGIFHWADDR) of %s is type %d "
231 "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n\n", ifname
,
232 if_hwaddr
.ifr_hwaddr
.sa_family
, hwaddr
[0], hwaddr
[1],
233 hwaddr
[2], hwaddr
[3], hwaddr
[4], hwaddr
[5]);
237 #endif /* __linux__ */
239 bb_debug_dump_packet(outpack
, pktsize
);
241 /* append the password if specified */
242 if (wol_passwd_sz
> 0) {
243 memcpy(outpack
+pktsize
, wol_passwd
, wol_passwd_sz
);
244 pktsize
+= wol_passwd_sz
;
247 bb_debug_dump_packet(outpack
, pktsize
);
249 /* This is necessary for broadcasts to work */
250 if (flags
/* & 1 OPT_BROADCAST */) {
251 if (setsockopt_broadcast(s
) != 0)
252 bb_perror_msg("SO_BROADCAST");
255 #if defined(PF_PACKET)
258 strncpy_IFNAMSIZ(ifr
.ifr_name
, ifname
);
259 xioctl(s
, SIOCGIFINDEX
, &ifr
);
260 memset(&whereto
, 0, sizeof(whereto
));
261 whereto
.sll_family
= AF_PACKET
;
262 whereto
.sll_ifindex
= ifr
.ifr_ifindex
;
263 /* The manual page incorrectly claims the address must be filled.
264 We do so because the code may change to match the docs. */
265 whereto
.sll_halen
= ETH_ALEN
;
266 memcpy(whereto
.sll_addr
, outpack
, ETH_ALEN
);
269 whereto
.sa_family
= 0;
270 strcpy(whereto
.sa_data
, ifname
);
272 xsendto(s
, outpack
, pktsize
, (struct sockaddr
*)&whereto
, sizeof(whereto
));
273 if (ENABLE_FEATURE_CLEAN_UP
)