1 #include <stdio.h>
2 #include <fcntl.h>
3 #include <unistd.h>
4 #include <sys/ioctl.h>
5 #include <linux/dm-ioctl.h>
6 #include <stdlib.h>
7 #include <string.h>
8
9 #define DM_CRYPT_BUF_SIZE 4096
10
ioctl_init(struct dm_ioctl * io,size_t dataSize,const char * name,unsigned flags)11 static void ioctl_init(struct dm_ioctl *io, size_t dataSize, const char *name, unsigned flags)
12 {
13 memset(io, 0, dataSize);
14 io->data_size = dataSize;
15 io->data_start = sizeof(struct dm_ioctl);
16 io->version[0] = 4;
17 io->version[1] = 0;
18 io->version[2] = 0;
19 io->flags = flags;
20 if (name) {
21 strncpy(io->name, name, sizeof(io->name));
22 }
23 }
24
main(int argc,char * argv[])25 int main(int argc, char *argv[])
26 {
27 char buffer[DM_CRYPT_BUF_SIZE];
28 struct dm_ioctl *io;
29 struct dm_target_versions *v;
30 int i;
31 int fd;
32
33 fd = open("/dev/device-mapper", O_RDWR);
34 if (fd < 0) {
35 fprintf(stderr, "Cannot open /dev/device-mapper\n");
36 exit(1);
37 }
38
39 io = (struct dm_ioctl *) buffer;
40
41 ioctl_init(io, DM_CRYPT_BUF_SIZE, NULL, 0);
42
43 if (ioctl(fd, DM_LIST_VERSIONS, io)) {
44 fprintf(stderr, "ioctl(DM_LIST_VERSIONS) returned an error\n");
45 exit(1);
46 }
47
48 /* Iterate over the returned versions, and print each subsystem's version */
49 v = (struct dm_target_versions *) &buffer[sizeof(struct dm_ioctl)];
50 while (v->next) {
51 printf("%s: %d.%d.%d\n", v->name, v->version[0], v->version[1], v->version[2]);
52 v = (struct dm_target_versions *)(((char *)v) + v->next);
53 }
54
55 close(fd);
56 exit(0);
57 }
58
59