1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (C) 2006, 2007, 2008, 2009, 2010 Marc Balmer <marc@msys.ch>
5 * Copyright (C) 2000 Eugene M. Kim. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Author's name may not be used endorse or promote products derived
14 * from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
25 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26 * POSSIBILITY OF SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD: stable/12/usr.sbin/wake/wake.c 326276 2017-11-27 15:37:16Z pfg $");
31
32 #include <sys/ioctl.h>
33 #include <sys/socket.h>
34 #include <sys/time.h>
35 #include <net/bpf.h>
36 #include <net/if.h>
37 #include <net/if_dl.h>
38 #include <net/if_types.h>
39 #include <netinet/in.h>
40 #include <netinet/if_ether.h>
41
42 #include <err.h>
43 #include <fcntl.h>
44 #include <ifaddrs.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49
50 #define _PATH_BPF "/dev/bpf"
51
52 #ifndef SYNC_LEN
53 #define SYNC_LEN 6
54 #endif
55
56 #ifndef DESTADDR_COUNT
57 #define DESTADDR_COUNT 16
58 #endif
59
60 static int bind_if_to_bpf(char const *ifname, int bpf);
61 static int find_ether(char *dst, size_t len);
62 static int get_ether(char const *text, struct ether_addr *addr);
63 static int send_wakeup(int bpf, struct ether_addr const *addr);
64 static void usage(void);
65 static int wake(int bpf, const char *host);
66
67 static void
usage(void)68 usage(void)
69 {
70
71 (void)fprintf(stderr, "usage: wake [interface] lladdr [lladdr ...]\n");
72 exit(1);
73 }
74
75 static int
wake(int bpf,const char * host)76 wake(int bpf, const char *host)
77 {
78 struct ether_addr macaddr;
79
80 if (get_ether(host, &macaddr) == -1)
81 return (-1);
82
83 return (send_wakeup(bpf, &macaddr));
84 }
85
86 static int
bind_if_to_bpf(char const * ifname,int bpf)87 bind_if_to_bpf(char const *ifname, int bpf)
88 {
89 struct ifreq ifr;
90 u_int dlt;
91
92 if (strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)) >=
93 sizeof(ifr.ifr_name))
94 return (-1);
95
96 if (ioctl(bpf, BIOCSETIF, &ifr) == -1)
97 return (-1);
98
99 if (ioctl(bpf, BIOCGDLT, &dlt) == -1)
100 return (-1);
101
102 if (dlt != DLT_EN10MB)
103 return (-1);
104
105 return (0);
106 }
107
108 static int
find_ether(char * dst,size_t len)109 find_ether(char *dst, size_t len)
110 {
111 struct ifaddrs *ifap, *ifa;
112 struct sockaddr_dl *sdl = NULL;
113 int nifs;
114
115 if (dst == NULL || len == 0)
116 return (0);
117
118 if (getifaddrs(&ifap) != 0)
119 return (-1);
120
121 /* XXX also check the link state */
122 for (nifs = 0, ifa = ifap; ifa; ifa = ifa->ifa_next)
123 if (ifa->ifa_addr->sa_family == AF_LINK &&
124 ifa->ifa_flags & IFF_UP && ifa->ifa_flags & IFF_RUNNING) {
125 sdl = (struct sockaddr_dl *)ifa->ifa_addr;
126 if (sdl->sdl_type == IFT_ETHER) {
127 strlcpy(dst, ifa->ifa_name, len);
128 nifs++;
129 }
130 }
131
132 freeifaddrs(ifap);
133 return (nifs == 1 ? 0 : -1);
134 }
135
136 static int
get_ether(char const * text,struct ether_addr * addr)137 get_ether(char const *text, struct ether_addr *addr)
138 {
139 struct ether_addr *paddr;
140
141 paddr = ether_aton(text);
142 if (paddr != NULL) {
143 *addr = *paddr;
144 return (0);
145 }
146 if (ether_hostton(text, addr)) {
147 warnx("no match for host %s found", text);
148 return (-1);
149 }
150 return (0);
151 }
152
153 static int
send_wakeup(int bpf,struct ether_addr const * addr)154 send_wakeup(int bpf, struct ether_addr const *addr)
155 {
156 struct {
157 struct ether_header hdr;
158 u_char data[SYNC_LEN + ETHER_ADDR_LEN * DESTADDR_COUNT];
159 } __packed pkt;
160 u_char *p;
161 ssize_t bw;
162 ssize_t len;
163 int i;
164
165 (void)memset(pkt.hdr.ether_dhost, 0xff, sizeof(pkt.hdr.ether_dhost));
166 pkt.hdr.ether_type = htons(0);
167 (void)memset(pkt.data, 0xff, SYNC_LEN);
168 for (p = pkt.data + SYNC_LEN, i = 0; i < DESTADDR_COUNT;
169 p += ETHER_ADDR_LEN, i++)
170 bcopy(addr->octet, p, ETHER_ADDR_LEN);
171 p = (u_char *)&pkt;
172 len = sizeof(pkt);
173 bw = 0;
174 while (len) {
175 if ((bw = write(bpf, p, len)) == -1) {
176 warn("write()");
177 return (-1);
178 }
179 len -= bw;
180 p += bw;
181 }
182 return (0);
183 }
184
185 int
main(int argc,char * argv[])186 main(int argc, char *argv[])
187 {
188 int bpf, n, rval;
189 char ifname[IF_NAMESIZE];
190
191 if (argc < 2)
192 usage();
193
194 if ((bpf = open(_PATH_BPF, O_RDWR)) == -1)
195 err(1, "Cannot open bpf interface");
196
197 n = 2;
198 if (bind_if_to_bpf(argv[1], bpf) == -1) {
199 if (find_ether(ifname, sizeof(ifname)))
200 err(1, "Failed to determine ethernet interface");
201 if (bind_if_to_bpf(ifname, bpf) == -1)
202 err(1, "Cannot bind to interface `%s'", ifname);
203 --n;
204 } else
205 strlcpy(ifname, argv[1], sizeof(ifname));
206
207 if (n >= argc)
208 usage();
209 rval = 0;
210 for (; n < argc; n++) {
211 if (wake(bpf, argv[n]) != 0) {
212 rval = 1;
213 warn("Cannot send Wake on LAN frame over `%s' to `%s'",
214 ifname, argv[n]);
215 }
216 }
217 exit(rval);
218 }
219