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) puts("");
100 # define bb_debug_msg(fmt, args...)
101 # define bb_debug_dump_packet(outpack, pktsize)
104 static inline void get_dest_addr(const char *arg, struct ether_addr *eaddr);
105 static inline int get_fill(unsigned char *pkt, struct ether_addr *eaddr, int broadcast);
106 static inline int get_wol_pw(const char *ethoptarg, unsigned char *wol_passwd);
108 int ether_wake_main(int argc, char *argv[])
110 char *ifname = "eth0", *pass = NULL;
112 unsigned char wol_passwd[6];
113 int wol_passwd_sz = 0;
115 int s; /* Raw socket */
117 unsigned char outpack[1000];
119 struct ether_addr eaddr;
120 struct whereto_t whereto; /* who to wake up */
122 /* handle misc user options */
123 flags = getopt32(argc, argv, "bi:p:", &ifname, &pass);
127 wol_passwd_sz = get_wol_pw(pass, wol_passwd);
129 /* create the raw socket */
132 /* now that we have a raw socket we can drop root */
135 /* look up the dest mac address */
136 get_dest_addr(argv[optind], &eaddr);
138 /* fill out the header of the packet */
139 pktsize = get_fill(outpack, &eaddr, flags /*& 1 [OPT_BROADCAST]*/);
141 bb_debug_dump_packet(outpack, pktsize);
143 /* Fill in the source address, if possible. */
146 struct ifreq if_hwaddr;
148 strncpy(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
149 if (ioctl(s, SIOCGIFHWADDR, &if_hwaddr) < 0)
150 bb_perror_msg_and_die("SIOCGIFHWADDR on %s failed", ifname);
152 memcpy(outpack+6, if_hwaddr.ifr_hwaddr.sa_data, 6);
156 unsigned char *hwaddr = if_hwaddr.ifr_hwaddr.sa_data;
157 printf("The hardware address (SIOCGIFHWADDR) of %s is type %d "
158 "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n\n", ifname,
159 if_hwaddr.ifr_hwaddr.sa_family, hwaddr[0], hwaddr[1],
160 hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]);
164 #endif /* __linux__ */
166 bb_debug_dump_packet(outpack, pktsize);
168 /* append the password if specified */
169 if (wol_passwd_sz > 0) {
170 memcpy(outpack+pktsize, wol_passwd, wol_passwd_sz);
171 pktsize += wol_passwd_sz;
174 bb_debug_dump_packet(outpack, pktsize);
176 /* This is necessary for broadcasts to work */
177 if (flags /*& 1 [OPT_BROADCAST]*/) {
178 if (setsockopt_broadcast(s) < 0)
179 bb_perror_msg("SO_BROADCAST");
182 #if defined(PF_PACKET)
185 strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
186 if (ioctl(s, SIOCGIFINDEX, &ifr) == -1)
187 bb_perror_msg_and_die("SIOCGIFINDEX");
188 memset(&whereto, 0, sizeof(whereto));
189 whereto.sll_family = AF_PACKET;
190 whereto.sll_ifindex = ifr.ifr_ifindex;
191 /* The manual page incorrectly claims the address must be filled.
192 We do so because the code may change to match the docs. */
193 whereto.sll_halen = ETH_ALEN;
194 memcpy(whereto.sll_addr, outpack, ETH_ALEN);
197 whereto.sa_family = 0;
198 strcpy(whereto.sa_data, ifname);
201 if (sendto(s, outpack, pktsize, 0, (struct sockaddr *)&whereto, sizeof(whereto)) < 0)
202 bb_perror_msg(bb_msg_write_error);
209 /* Convert the host ID string to a MAC address.
210 * The string may be a:
215 static inline void get_dest_addr(const char *hostid, struct ether_addr *eaddr)
217 struct ether_addr *eap;
219 eap = ether_aton(hostid);
222 bb_debug_msg("The target station address is %s\n\n", ether_ntoa(eaddr));
223 #if !defined(__UCLIBC__)
224 } else if (ether_hostton(hostid, eaddr) == 0) {
225 bb_debug_msg("Station address for hostname %s is %s\n\n", hostid, ether_ntoa(eaddr));
227 # warning Need to implement ether_hostton() for uClibc
233 static inline int get_fill(unsigned char *pkt, struct ether_addr *eaddr, int broadcast)
236 unsigned char *station_addr = eaddr->ether_addr_octet;
239 memset(pkt+0, 0xff, 6);
241 memcpy(pkt, station_addr, 6);
242 memcpy(pkt+6, station_addr, 6);
243 pkt[12] = 0x08; /* Or 0x0806 for ARP, 0x8035 for RARP */
247 memset(pkt+offset, 0xff, 6);
250 for (i = 0; i < 16; ++i) {
251 memcpy(pkt+offset, station_addr, 6);
258 static inline int get_wol_pw(const char *ethoptarg, unsigned char *wol_passwd)
263 /* handle MAC format */
264 byte_cnt = sscanf(ethoptarg, "%2x:%2x:%2x:%2x:%2x:%2x",
265 &passwd[0], &passwd[1], &passwd[2],
266 &passwd[3], &passwd[4], &passwd[5]);
267 /* handle IP format */
269 byte_cnt = sscanf(ethoptarg, "%d.%d.%d.%d",
270 &passwd[0], &passwd[1], &passwd[2], &passwd[3]);
272 bb_error_msg("cannot read Wake-On-LAN pass");
276 for (i = 0; i < byte_cnt; ++i)
277 wol_passwd[i] = passwd[i];
279 bb_debug_msg("password: %2.2x %2.2x %2.2x %2.2x (%d)\n\n",
280 wol_passwd[0], wol_passwd[1], wol_passwd[2], wol_passwd[3],