Author: nwf
Description: Allow creation of IFF_TUN devices

Index: uml-utilities/tunctl/tunctl.c
===================================================================
--- uml-utilities.orig/tunctl/tunctl.c
+++ uml-utilities/tunctl/tunctl.c
@@ -28,6 +28,7 @@ static void Usage(char *name)
   fprintf(stderr, "The default tun clone device is /dev/net/tun - some systems"
 	  " use\n/dev/misc/net/tun instead\n\n");
   fprintf(stderr, "-b will result in brief output (just the device name)\n");
+  fprintf(stderr, "-3 will open the interface in TUN mode, not TAP mode.\n");
   exit(1);
 }
 
@@ -38,10 +39,10 @@ int main(int argc, char **argv)
   struct group *gr;
   uid_t owner = -1;
   gid_t group = -1;
-  int tap_fd, opt, delete = 0, brief = 0;
+  int tap_fd, opt, delete = 0, brief = 0, tun_mode = 0;
   char *tun = "", *file = "/dev/net/tun", *name = argv[0], *end;
 
-  while((opt = getopt(argc, argv, "bd:f:t:u:g:")) > 0){
+  while((opt = getopt(argc, argv, "3bd:f:t:u:g:")) > 0){
     switch(opt) {
       case 'b':
         brief = 1;
@@ -83,6 +84,9 @@ int main(int argc, char **argv)
       case 't':
         tun = optarg;
         break;
+      case '3':
+        tun_mode = 1;
+        break;
       case 'h':
       default:
         Usage(name);
@@ -102,8 +106,7 @@ int main(int argc, char **argv)
   }
 
   memset(&ifr, 0, sizeof(ifr));
-
-  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+  ifr.ifr_flags = (tun_mode ? IFF_TUN : IFF_TAP) | IFF_NO_PI;
   strncpy(ifr.ifr_name, tun, sizeof(ifr.ifr_name) - 1);
   if(ioctl(tap_fd, TUNSETIFF, (void *) &ifr) < 0){
     perror("TUNSETIFF");