main.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <sys/types.h>
   4 #include <unistd.h>
   5
   6 // This program will execute the openvpn executable
   7 // passing in through the command line parameters
   8 // The purpose is to allow openvpn to be executed
   9 // as a different user (e.g. root)
  10
  11 int main (int argc, char *argv[]) {
  12     char * const command = "openvpn";
  13     char ** newargv = malloc (sizeof(char*) * (argc + 1));
  14     int arg;
  15
  16     if (newargv != NULL) {
  17         // Transfer the arguments passed in to a new argument array
  18         for (arg = 0; arg < argc; arg++) {
  19             newargv[arg] = argv[arg];
  20         }
  21         // Ensure the argument list is NULL terminated (for execvp)
  22         newargv[argc] = NULL;
  23         // Ensure the first argument matches the command
  24         newargv[0] = command;
  25
  26         // Execute the external command
  27         //setuid (0);
  28         execvp (command, newargv);
  29
  30         // This part of the code shouldn't be reached unless there was a problem
  31         fprintf (stderr, "Error executing openvpn\n");
  32
  33         free (newargv);
  34     }
  35     else {
  36         // There was a problem with thee malloc call
  37         fprintf (stderr, "Error allocating memory for command argument list\n");
  38     }
  39     return 0;
  40 }
  41