--- freebsd/tun_dev.c.orig 2008-01-07 14:36:10.000000000 -0800 +++ freebsd/tun_dev.c 2016-09-19 20:06:49.919502000 -0700 @@ -35,6 +35,8 @@ #include "vtun.h" #include "lib.h" +extern int extended_mode; + /* * Allocate TUN device, returns opened fd. * Stores dev name in the first arg(must be large enough). @@ -58,10 +60,8 @@ } } if( fd > -1 ){ - i=0; - /* Disable extended modes */ - ioctl(fd, TUNSLMODE, &i); - ioctl(fd, TUNSIFHEAD, &i); + ioctl(fd, TUNSLMODE, &extended_mode); + ioctl(fd, TUNSIFHEAD, &extended_mode); } return fd; }