busybox/networking/ether-wake.c

/* 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__)
	} 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(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
		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(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
		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;
}
1	niro	532	/* vi: set sw=4 ts=4: */
2			/*
3			* ether-wake.c - Send a magic packet to wake up sleeping machines.
4			*
5			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
6			*
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/";
10			*/
11
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"
14			*
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"
20			*
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"
25			*
26			* Options:\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"
35			* -p 192.168.1.1\n";
36			*
37			*
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.
42			*
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.
46			*
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.
50			*
51			* The author may be reached as becker@scyld, or C/O
52			* Scyld Computing Corporation
53			* 914 Bay Ridge Road, Suite 220
54			* Annapolis MD 21403
55			*
56			* Notes:
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.
61			*
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.
65			*/
66
67
68			#include <netpacket/packet.h>
69			#include <net/ethernet.h>
70			#include <netinet/ether.h>
71			#include <linux/if.h>
72
73	niro	816	#include "libbb.h"
74	niro	532
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.
78			*/
79			#ifdef PF_PACKET
80			# define whereto_t sockaddr_ll
81			# define make_socket() xsocket(PF_PACKET, SOCK_RAW, 0)
82			#else
83			# define whereto_t sockaddr
84			# define make_socket() xsocket(AF_INET, SOCK_PACKET, SOCK_PACKET)
85			#endif
86
87			#ifdef DEBUG
88			# define bb_debug_msg(fmt, args...) fprintf(stderr, fmt, ## args)
89			void bb_debug_dump_packet(unsigned char *outpack, int pktsize)
90			{
91			int i;
92			printf("packet dump:\n");
93			for (i = 0; i < pktsize; ++i) {
94			printf("%2.2x ", outpack[i]);
95	niro	816	if (i % 20 == 19) bb_putchar('\n');
96	niro	532	}
97			printf("\n\n");
98			}
99			#else
100	niro	816	# define bb_debug_msg(fmt, args...) ((void)0)
101			# define bb_debug_dump_packet(outpack, pktsize) ((void)0)
102	niro	532	#endif
103
104	niro	816	/* Convert the host ID string to a MAC address.
105			* The string may be a:
106			* Host name
107			* IP address string
108			* MAC address string
109			*/
110			static void get_dest_addr(const char hostid, struct ether_addr eaddr)
111			{
112			struct ether_addr *eap;
113	niro	532
114	niro	816	eap = ether_aton(hostid);
115			if (eap) {
116			eaddr = eap;
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));
121			#endif
122			} else
123			bb_show_usage();
124			}
125
126			static int get_fill(unsigned char pkt, struct ether_addr eaddr, int broadcast)
127	niro	532	{
128	niro	816	int i;
129			unsigned char *station_addr = eaddr->ether_addr_octet;
130
131			memset(pkt, 0xff, 6);
132			if (!broadcast)
133			memcpy(pkt, station_addr, 6);
134			pkt += 6;
135
136			memcpy(pkt, station_addr, 6); /* 6 */
137			pkt += 6;
138
139			pkt++ = 0x08; / 12 / / Or 0x0806 for ARP, 0x8035 for RARP */
140			pkt++ = 0x42; / 13 */
141
142			memset(pkt, 0xff, 6); /* 14 */
143
144			for (i = 0; i < 16; ++i) {
145			pkt += 6;
146			memcpy(pkt, station_addr, 6); /* 20,26,32,... */
147			}
148
149			return 20 + 166; / length of packet */
150			}
151
152			static int get_wol_pw(const char ethoptarg, unsigned char wol_passwd)
153			{
154			unsigned passwd[6];
155			int byte_cnt, i;
156
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?
163			if (byte_cnt < 4)
164			byte_cnt = sscanf(ethoptarg, "%u.%u.%u.%u",
165			&passwd[0], &passwd[1], &passwd[2], &passwd[3]);
166			if (byte_cnt < 4) {
167			bb_error_msg("cannot read Wake-On-LAN pass");
168			return 0;
169			}
170			// TODO: check invalid numbers >255??
171			for (i = 0; i < byte_cnt; ++i)
172			wol_passwd[i] = passwd[i];
173
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],
176			byte_cnt);
177
178			return byte_cnt;
179			}
180
181			int ether_wake_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
182			int ether_wake_main(int argc UNUSED_PARAM, char **argv)
183			{
184			const char *ifname = "eth0";
185			char *pass;
186			unsigned flags;
187	niro	532	unsigned char wol_passwd[6];
188			int wol_passwd_sz = 0;
189			int s; /* Raw socket */
190			int pktsize;
191			unsigned char outpack[1000];
192
193			struct ether_addr eaddr;
194			struct whereto_t whereto; /* who to wake up */
195
196			/* handle misc user options */
197	niro	816	opt_complementary = "=1";
198			flags = getopt32(argv, "bi:p:", &ifname, &pass);
199			if (flags & 4) /* -p */
200	niro	532	wol_passwd_sz = get_wol_pw(pass, wol_passwd);
201	niro	816	flags &= 1; /* we further interested only in -b [bcast] flag */
202	niro	532
203			/* create the raw socket */
204			s = make_socket();
205
206			/* now that we have a raw socket we can drop root */
207	niro	816	/* xsetuid(getuid()); - but save on code size... */
208	niro	532
209			/* look up the dest mac address */
210			get_dest_addr(argv[optind], &eaddr);
211
212			/* fill out the header of the packet */
213	niro	816	pktsize = get_fill(outpack, &eaddr, flags /* & 1 OPT_BROADCAST */);
214	niro	532
215			bb_debug_dump_packet(outpack, pktsize);
216
217			/* Fill in the source address, if possible. */
218			#ifdef __linux__
219			{
220			struct ifreq if_hwaddr;
221
222			strncpy(if_hwaddr.ifr_name, ifname, sizeof(if_hwaddr.ifr_name));
223	niro	816	ioctl_or_perror_and_die(s, SIOCGIFHWADDR, &if_hwaddr, "SIOCGIFHWADDR on %s failed", ifname);
224	niro	532
225			memcpy(outpack+6, if_hwaddr.ifr_hwaddr.sa_data, 6);
226
227			# ifdef DEBUG
228			{
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]);
234			}
235			# endif
236			}
237			#endif /* __linux__ */
238
239			bb_debug_dump_packet(outpack, pktsize);
240
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;
245			}
246
247			bb_debug_dump_packet(outpack, pktsize);
248
249			/* This is necessary for broadcasts to work */
250	niro	816	if (flags /* & 1 OPT_BROADCAST */) {
251			if (setsockopt_broadcast(s) != 0)
252	niro	532	bb_perror_msg("SO_BROADCAST");
253			}
254
255			#if defined(PF_PACKET)
256			{
257			struct ifreq ifr;
258			strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
259	niro	816	xioctl(s, SIOCGIFINDEX, &ifr);
260	niro	532	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);
267			}
268			#else
269			whereto.sa_family = 0;
270			strcpy(whereto.sa_data, ifname);
271			#endif
272	niro	816	xsendto(s, outpack, pktsize, (struct sockaddr *)&whereto, sizeof(whereto));
273			if (ENABLE_FEATURE_CLEAN_UP)
274			close(s);
275	niro	532	return EXIT_SUCCESS;
276			}