TUN_F_CSUM 86 include/uapi/linux/if_tun.h #define TUN_F_CSUM 0x01 /* You can hand me unchecksummed packets. */ TUN_F_CSUM 86 tools/include/uapi/linux/if_tun.h #define TUN_F_CSUM 0x01 /* You can hand me unchecksummed packets. */