}
-/**
- * Run the given command and wait for it to complete.
- *
- * @param file name of the binary to run
- * @param cmd command line arguments (as given to 'execv')
- * @return 0 on success, 1 on any error
- */
-static int
-fork_and_exec (const char *file,
- char *const cmd[])
-{
- int status;
- pid_t pid;
- pid_t ret;
-
- pid = fork ();
- if (-1 == pid)
- {
- fprintf (stderr,
- "fork failed: %s\n",
- strerror (errno));
- return 1;
- }
- if (0 == pid)
- {
- /* we are the child process */
- /* close stdin/stdout to not cause interference
- with the helper's main protocol! */
- (void) close (0);
- (void) close (1);
- (void) execv (file, cmd);
- /* can only get here on error */
- fprintf (stderr,
- "exec `%s' failed: %s\n",
- file,
- strerror (errno));
- _exit (1);
- }
- /* keep running waitpid as long as the only error we get is 'EINTR' */
- while ( (-1 == (ret = waitpid (pid, &status, 0))) &&
- (errno == EINTR) );
- if (-1 == ret)
- {
- fprintf (stderr,
- "waitpid failed: %s\n",
- strerror (errno));
- return 1;
- }
- if (! (WIFEXITED (status) && (0 == WEXITSTATUS (status))))
- return 1;
- /* child process completed and returned success, we're happy */
- return 0;
-}
-
int
main (int argc, char *const *argv)
{
- char *sbin_sysctl;
- char *const sysctl_args[] = {"sysctl", "-w", "net.ipv4.conf.default.rp_filter=0", NULL};
-
- if (0 == ACCESS ("/sbin/sysctl", X_OK))
- sbin_sysctl = "/sbin/sysctl";
- else if (0 == ACCESS ("/usr/sbin/sysctl", X_OK))
- sbin_sysctl = "/usr/sbin/sysctl";
- else
- {
- fprintf (stderr,
- "Fatal: executable sysctl not found in approved directories: %s\n",
- strerror (errno));
- return 0;
- }
-
- if (0 != fork_and_exec (sbin_sysctl, sysctl_args))
- {
- fprintf (stderr,
- "Failed to enable IPv4 forwarding. Will continue anyway.\n");
- return 1;
- }
-
if (0 != ACCESS ("/dev/net/tun", R_OK))
{
GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR,