1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
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 #include <sys/ioctl.h>
31 #include <sys/socket.h>
32 #include <sys/time.h>
33 #include <net/bpf.h>
34 #include <net/if.h>
35 #include <net/if_dl.h>
36 #include <net/if_types.h>
37 #include <netinet/in.h>
38 #include <netinet/if_ether.h>
39
40 #include <err.h>
41 #include <fcntl.h>
42 #include <ifaddrs.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47
48 #define _PATH_BPF "/dev/bpf"
49
50 #ifndef SYNC_LEN
51 #define SYNC_LEN 6
52 #endif
53
54 #ifndef DESTADDR_COUNT
55 #define DESTADDR_COUNT 16
56 #endif
57
58 static int bind_if_to_bpf(char const *ifname, int bpf);
59 static int find_ether(char *dst, size_t len);
60 static int get_ether(char const *text, struct ether_addr *addr);
61 static int send_wakeup(int bpf, struct ether_addr const *addr);
62 static void usage(void);
63 static int wake(int bpf, const char *host);
64
65 static void
usage(void)66 usage(void)
67 {
68
69 (void)fprintf(stderr, "usage: wake [interface] lladdr [lladdr ...]\n");
70 exit(1);
71 }
72
73 static int
wake(int bpf,const char * host)74 wake(int bpf, const char *host)
75 {
76 struct ether_addr macaddr;
77
78 if (get_ether(host, &macaddr) == -1)
79 return (-1);
80
81 return (send_wakeup(bpf, &macaddr));
82 }
83
84 static int
bind_if_to_bpf(char const * ifname,int bpf)85 bind_if_to_bpf(char const *ifname, int bpf)
86 {
87 struct ifreq ifr;
88 u_int dlt;
89
90 if (strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name)) >=
91 sizeof(ifr.ifr_name))
92 return (-1);
93
94 if (ioctl(bpf, BIOCSETIF, &ifr) == -1)
95 return (-1);
96
97 if (ioctl(bpf, BIOCGDLT, &dlt) == -1)
98 return (-1);
99
100 if (dlt != DLT_EN10MB)
101 return (-1);
102
103 return (0);
104 }
105
106 static int
find_ether(char * dst,size_t len)107 find_ether(char *dst, size_t len)
108 {
109 struct ifaddrs *ifap, *ifa;
110 struct sockaddr_dl *sdl = NULL;
111 int nifs;
112
113 if (dst == NULL || len == 0)
114 return (0);
115
116 if (getifaddrs(&ifap) != 0)
117 return (-1);
118
119 /* XXX also check the link state */
120 for (nifs = 0, ifa = ifap; ifa; ifa = ifa->ifa_next)
121 if (ifa->ifa_addr->sa_family == AF_LINK &&
122 ifa->ifa_flags & IFF_UP && ifa->ifa_flags & IFF_RUNNING) {
123 sdl = (struct sockaddr_dl *)ifa->ifa_addr;
124 if (sdl->sdl_type == IFT_ETHER) {
125 strlcpy(dst, ifa->ifa_name, len);
126 nifs++;
127 }
128 }
129
130 freeifaddrs(ifap);
131 return (nifs == 1 ? 0 : -1);
132 }
133
134 static int
get_ether(char const * text,struct ether_addr * addr)135 get_ether(char const *text, struct ether_addr *addr)
136 {
137 struct ether_addr *paddr;
138
139 paddr = ether_aton(text);
140 if (paddr != NULL) {
141 *addr = *paddr;
142 return (0);
143 }
144 if (ether_hostton(text, addr)) {
145 warnx("no match for host %s found", text);
146 return (-1);
147 }
148 return (0);
149 }
150
151 static int
send_wakeup(int bpf,struct ether_addr const * addr)152 send_wakeup(int bpf, struct ether_addr const *addr)
153 {
154 struct {
155 struct ether_header hdr;
156 u_char data[SYNC_LEN + ETHER_ADDR_LEN * DESTADDR_COUNT];
157 } __packed pkt;
158 u_char *p;
159 ssize_t bw;
160 ssize_t len;
161 int i;
162
163 (void)memset(pkt.hdr.ether_dhost, 0xff, sizeof(pkt.hdr.ether_dhost));
164 pkt.hdr.ether_type = htons(0);
165 (void)memset(pkt.data, 0xff, SYNC_LEN);
166 for (p = pkt.data + SYNC_LEN, i = 0; i < DESTADDR_COUNT;
167 p += ETHER_ADDR_LEN, i++)
168 bcopy(addr->octet, p, ETHER_ADDR_LEN);
169 p = (u_char *)&pkt;
170 len = sizeof(pkt);
171 bw = 0;
172 while (len) {
173 if ((bw = write(bpf, p, len)) == -1) {
174 warn("write()");
175 return (-1);
176 }
177 len -= bw;
178 p += bw;
179 }
180 return (0);
181 }
182
183 int
main(int argc,char * argv[])184 main(int argc, char *argv[])
185 {
186 int bpf, n, rval;
187 char ifname[IF_NAMESIZE];
188
189 if (argc < 2)
190 usage();
191
192 if ((bpf = open(_PATH_BPF, O_RDWR)) == -1)
193 err(1, "Cannot open bpf interface");
194
195 n = 2;
196 if (bind_if_to_bpf(argv[1], bpf) == -1) {
197 if (find_ether(ifname, sizeof(ifname)))
198 err(1, "Failed to determine ethernet interface");
199 if (bind_if_to_bpf(ifname, bpf) == -1)
200 err(1, "Cannot bind to interface `%s'", ifname);
201 --n;
202 } else
203 strlcpy(ifname, argv[1], sizeof(ifname));
204
205 if (n >= argc)
206 usage();
207 rval = 0;
208 for (; n < argc; n++) {
209 if (wake(bpf, argv[n]) != 0) {
210 rval = 1;
211 warn("Cannot send Wake on LAN frame over `%s' to `%s'",
212 ifname, argv[n]);
213 }
214 }
215 exit(rval);
216 }
217