networking/ether-wake.c - codeaurora/busybox - Gitiles

 /* 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) puts("");
 	}
 	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__)
 	} 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);
 int ether_wake_main(int argc, 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(argc, 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(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
 		if (ioctl(s, SIOCGIFHWADDR, &if_hwaddr) != 0)
 			bb_perror_msg_and_die("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(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
 		if (ioctl(s, SIOCGIFINDEX, &ifr) != 0)
 			bb_perror_msg_and_die("SIOCGIFINDEX");
 		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;
 }
	/* 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) puts("");
	}
	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__)
	} 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 + 166; / 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);
	int ether_wake_main(int argc, 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(argc, 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(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
	if (ioctl(s, SIOCGIFHWADDR, &if_hwaddr) != 0)
	bb_perror_msg_and_die("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(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
	if (ioctl(s, SIOCGIFINDEX, &ifr) != 0)
	bb_perror_msg_and_die("SIOCGIFINDEX");
	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;
	}