1 /* insmod.c - Load a module into the Linux kernel.
2  *
3  * Copyright 2012 Elie De Brauwer <eliedebrauwer@gmail.com>
4 
5 USE_INSMOD(NEWTOY(insmod, "<1", TOYFLAG_SBIN|TOYFLAG_NEEDROOT))
6 
7 config INSMOD
8   bool "insmod"
9   default y
10   help
11     usage: insmod MODULE [MODULE_OPTIONS]
12 
13     Load the module named MODULE passing options if given.
14 */
15 
16 #include "toys.h"
17 
18 #include <sys/syscall.h>
19 #ifdef SYS_finit_module
20 #define finit_module(fd, opts, flags) syscall(SYS_finit_module, fd, opts, flags)
21 #else
22 #define finit_module(a, b, c) (errno = ENOSYS)
23 #endif
24 #define init_module(mod, len, opts) syscall(SYS_init_module, mod, len, opts)
25 
insmod_main(void)26 void insmod_main(void)
27 {
28   int fd = xopenro(*toys.optargs);
29   int i, rc;
30 
31   i = 1;
32   while (toys.optargs[i] &&
33     strlen(toybuf) + strlen(toys.optargs[i]) + 2 < sizeof(toybuf))
34   {
35     strcat(toybuf, toys.optargs[i++]);
36     strcat(toybuf, " ");
37   }
38 
39   // finit_module was new in Linux 3.8, and doesn't work on stdin,
40   // so we fall back to init_module if necessary.
41   rc = finit_module(fd, toybuf, 0);
42   if (rc && (fd == 0 || errno == ENOSYS)) {
43     off_t len = 0;
44     char *path = !strcmp(*toys.optargs, "-") ? "/dev/stdin" : *toys.optargs;
45     char *buf = readfileat(AT_FDCWD, path, NULL, &len);
46 
47     rc = init_module(buf, len, toybuf);
48     if (CFG_TOYBOX_FREE) free(buf);
49   }
50 
51   if (rc) perror_exit("failed to load %s", toys.optargs[0]);
52 
53   if (CFG_TOYBOX_FREE) close(fd);
54 }
55