/* vi: set sw=4 ts=4: */ /* * ether-wake.c - Send a magic packet to wake up sleeping machines. * * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. * * Author: Donald Becker, http://www.scyld.com/"; http://www.scyld.com/wakeonlan.html * Busybox port: Christian Volkmann <haveaniceday@online.de> * Used version of ether-wake.c: v1.09 11/12/2003 Donald Becker, http://www.scyld.com/"; */ /* full usage according Donald Becker * usage: ether-wake [-i <ifname>] [-p aa:bb:cc:dd[:ee:ff]] 00:11:22:33:44:55\n" * * This program generates and transmits a Wake-On-LAN (WOL)\n" * \"Magic Packet\", used for restarting machines that have been\n" * soft-powered-down (ACPI D3-warm state).\n" * It currently generates the standard AMD Magic Packet format, with\n" * an optional password appended.\n" * * The single required parameter is the Ethernet MAC (station) address\n" * of the machine to wake or a host ID with known NSS 'ethers' entry.\n" * The MAC address may be found with the 'arp' program while the target\n" * machine is awake.\n" * * Options:\n" * -b Send wake-up packet to the broadcast address.\n" * -D Increase the debug level.\n" * -i ifname Use interface IFNAME instead of the default 'eth0'.\n" * -p <pw> Append the four or six byte password PW to the packet.\n" * A password is only required for a few adapter types.\n" * The password may be specified in ethernet hex format\n" * or dotted decimal (Internet address)\n" * -p 00:22:44:66:88:aa\n" * -p 192.168.1.1\n"; * * * This program generates and transmits a Wake-On-LAN (WOL) "Magic Packet", * used for restarting machines that have been soft-powered-down * (ACPI D3-warm state). It currently generates the standard AMD Magic Packet * format, with an optional password appended. * * This software may be used and distributed according to the terms * of the GNU Public License, incorporated herein by reference. * Contact the author for use under other terms. * * This source file was originally part of the network tricks package, and * is now distributed to support the Scyld Beowulf system. * Copyright 1999-2003 Donald Becker and Scyld Computing Corporation. * * The author may be reached as becker@scyld, or C/O * Scyld Computing Corporation * 914 Bay Ridge Road, Suite 220 * Annapolis MD 21403 * * Notes: * On some systems dropping root capability allows the process to be * dumped, traced or debugged. * If someone traces this program, they get control of a raw socket. * Linux handles this safely, but beware when porting this program. * * An alternative to needing 'root' is using a UDP broadcast socket, however * doing so only works with adapters configured for unicast+broadcast Rx * filter. That configuration consumes more power. */ #include <netpacket/packet.h> #include <net/ethernet.h> #include <netinet/ether.h> #include <linux/if.h> #include "libbb.h" /* Note: PF_INET, SOCK_DGRAM, IPPROTO_UDP would allow SIOCGIFHWADDR to * work as non-root, but we need SOCK_PACKET to specify the Ethernet * destination address. */ #ifdef PF_PACKET # define whereto_t sockaddr_ll # define make_socket() xsocket(PF_PACKET, SOCK_RAW, 0) #else # define whereto_t sockaddr # define make_socket() xsocket(AF_INET, SOCK_PACKET, SOCK_PACKET) #endif #ifdef DEBUG # define bb_debug_msg(fmt, args...) fprintf(stderr, fmt, ## args) void bb_debug_dump_packet(unsigned char *outpack, int pktsize) { int i; printf("packet dump:\n"); for (i = 0; i < pktsize; ++i) { printf("%2.2x ", outpack[i]); if (i % 20 == 19) bb_putchar('\n'); } printf("\n\n"); } #else # define bb_debug_msg(fmt, args...) ((void)0) # define bb_debug_dump_packet(outpack, pktsize) ((void)0) #endif /* Convert the host ID string to a MAC address. * The string may be a: * Host name * IP address string * MAC address string */ static void get_dest_addr(const char *hostid, struct ether_addr *eaddr) { struct ether_addr *eap; eap = ether_aton(hostid); if (eap) { *eaddr = *eap; bb_debug_msg("The target station address is %s\n\n", ether_ntoa(eaddr)); #if !defined(__UCLIBC_MAJOR__) \ || __UCLIBC_MAJOR__ > 0 \ || __UCLIBC_MINOR__ > 9 \ || (__UCLIBC_MINOR__ == 9 && __UCLIBC_SUBLEVEL__ >= 30) } else if (ether_hostton(hostid, eaddr) == 0) { bb_debug_msg("Station address for hostname %s is %s\n\n", hostid, ether_ntoa(eaddr)); #endif } else bb_show_usage(); } static int get_fill(unsigned char *pkt, struct ether_addr *eaddr, int broadcast) { int i; unsigned char *station_addr = eaddr->ether_addr_octet; memset(pkt, 0xff, 6); if (!broadcast) memcpy(pkt, station_addr, 6); pkt += 6; memcpy(pkt, station_addr, 6); /* 6 */ pkt += 6; *pkt++ = 0x08; /* 12 */ /* Or 0x0806 for ARP, 0x8035 for RARP */ *pkt++ = 0x42; /* 13 */ memset(pkt, 0xff, 6); /* 14 */ for (i = 0; i < 16; ++i) { pkt += 6; memcpy(pkt, station_addr, 6); /* 20,26,32,... */ } return 20 + 16*6; /* length of packet */ } static int get_wol_pw(const char *ethoptarg, unsigned char *wol_passwd) { unsigned passwd[6]; int byte_cnt, i; /* handle MAC format */ byte_cnt = sscanf(ethoptarg, "%2x:%2x:%2x:%2x:%2x:%2x", &passwd[0], &passwd[1], &passwd[2], &passwd[3], &passwd[4], &passwd[5]); /* handle IP format */ // FIXME: why < 4?? should it be < 6? if (byte_cnt < 4) byte_cnt = sscanf(ethoptarg, "%u.%u.%u.%u", &passwd[0], &passwd[1], &passwd[2], &passwd[3]); if (byte_cnt < 4) { bb_error_msg("cannot read Wake-On-LAN pass"); return 0; } // TODO: check invalid numbers >255?? for (i = 0; i < byte_cnt; ++i) wol_passwd[i] = passwd[i]; bb_debug_msg("password: %2.2x %2.2x %2.2x %2.2x (%d)\n\n", wol_passwd[0], wol_passwd[1], wol_passwd[2], wol_passwd[3], byte_cnt); return byte_cnt; } int ether_wake_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int ether_wake_main(int argc UNUSED_PARAM, char **argv) { const char *ifname = "eth0"; char *pass; unsigned flags; unsigned char wol_passwd[6]; int wol_passwd_sz = 0; int s; /* Raw socket */ int pktsize; unsigned char outpack[1000]; struct ether_addr eaddr; struct whereto_t whereto; /* who to wake up */ /* handle misc user options */ opt_complementary = "=1"; flags = getopt32(argv, "bi:p:", &ifname, &pass); if (flags & 4) /* -p */ wol_passwd_sz = get_wol_pw(pass, wol_passwd); flags &= 1; /* we further interested only in -b [bcast] flag */ /* create the raw socket */ s = make_socket(); /* now that we have a raw socket we can drop root */ /* xsetuid(getuid()); - but save on code size... */ /* look up the dest mac address */ get_dest_addr(argv[optind], &eaddr); /* fill out the header of the packet */ pktsize = get_fill(outpack, &eaddr, flags /* & 1 OPT_BROADCAST */); bb_debug_dump_packet(outpack, pktsize); /* Fill in the source address, if possible. */ #ifdef __linux__ { struct ifreq if_hwaddr; strncpy_IFNAMSIZ(if_hwaddr.ifr_name, ifname); ioctl_or_perror_and_die(s, SIOCGIFHWADDR, &if_hwaddr, "SIOCGIFHWADDR on %s failed", ifname); memcpy(outpack+6, if_hwaddr.ifr_hwaddr.sa_data, 6); # ifdef DEBUG { unsigned char *hwaddr = if_hwaddr.ifr_hwaddr.sa_data; printf("The hardware address (SIOCGIFHWADDR) of %s is type %d " "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x\n\n", ifname, if_hwaddr.ifr_hwaddr.sa_family, hwaddr[0], hwaddr[1], hwaddr[2], hwaddr[3], hwaddr[4], hwaddr[5]); } # endif } #endif /* __linux__ */ bb_debug_dump_packet(outpack, pktsize); /* append the password if specified */ if (wol_passwd_sz > 0) { memcpy(outpack+pktsize, wol_passwd, wol_passwd_sz); pktsize += wol_passwd_sz; } bb_debug_dump_packet(outpack, pktsize); /* This is necessary for broadcasts to work */ if (flags /* & 1 OPT_BROADCAST */) { if (setsockopt_broadcast(s) != 0) bb_perror_msg("SO_BROADCAST"); } #if defined(PF_PACKET) { struct ifreq ifr; strncpy_IFNAMSIZ(ifr.ifr_name, ifname); xioctl(s, SIOCGIFINDEX, &ifr); memset(&whereto, 0, sizeof(whereto)); whereto.sll_family = AF_PACKET; whereto.sll_ifindex = ifr.ifr_ifindex; /* The manual page incorrectly claims the address must be filled. We do so because the code may change to match the docs. */ whereto.sll_halen = ETH_ALEN; memcpy(whereto.sll_addr, outpack, ETH_ALEN); } #else whereto.sa_family = 0; strcpy(whereto.sa_data, ifname); #endif xsendto(s, outpack, pktsize, (struct sockaddr *)&whereto, sizeof(whereto)); if (ENABLE_FEATURE_CLEAN_UP) close(s); return EXIT_SUCCESS; }