LXR toybox/toys/other/insmod.c

   1/* insmod.c - Load a module into the Linux kernel.
   2 *
   3 * Copyright 2012 Elie De Brauwer <eliedebrauwer@gmail.com>
   4
   5USE_INSMOD(NEWTOY(insmod, "<1", TOYFLAG_SBIN|TOYFLAG_NEEDROOT))
   6
   7config 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
  26void 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