Windows 7 TUN bug fixing

src/adapter.rs

@@ -69,7 +69,7 @@ impl Adapter {
         let name_utf16: Vec<_> = name.encode_utf16().chain(std::iter::once(0)).collect();
         let tunnel_type_utf16: Vec<u16> = tunnel_type.encode_utf16().chain(std::iter::once(0)).collect();
 
-        let guid = match guid {
+        let mut guid = match guid {
             Some(guid) => guid,
             None => {
                 let mut guid: GUID = unsafe { std::mem::zeroed() };
@@ -88,6 +88,14 @@ impl Adapter {
         }
         let luid = crate::ffi::alias_to_luid(name)?;
         let index = crate::ffi::luid_to_index(&luid)?;
+        let real_guid = util::win_guid_to_u128(&crate::ffi::luid_to_guid(&luid)?);
+        if guid != real_guid {
+            let real_guid_s = util::guid_to_win_style_string(&GUID::from_u128(real_guid))?;
+            let guid_s = util::guid_to_win_style_string(&GUID::from_u128(guid))?;
+            let (major, minor, build) = util::get_windows_version()?;
+            log::warn!("Windows {major}.{minor}.{build} internal bug cause the GUID mismatch: Expected {guid_s}, got {real_guid_s}");
+            guid = real_guid;
+        }
         Ok(Arc::new(Adapter {
             adapter: UnsafeHandle(result),
             wintun: wintun.clone(),

src/util.rs

@@ -43,6 +43,18 @@ pub fn get_wintun_bin_pattern_path() -> std::io::Result<std::path::PathBuf> {
     Ok(dll_path.into())
 }
 
+//
+// WINAPI VOID RtlGetNtVersionNumbers (DWORD *MajorVersion, DWORD *MinorVersion, DWORD *BuildNumber);
+//
+pub(crate) fn get_windows_version() -> Result<(u32, u32, u32), libloading::Error> {
+    let library = unsafe { ::libloading::Library::new("ntdll")? };
+    type TheFn = unsafe extern "system" fn(*mut u32, *mut u32, *mut u32);
+    let func: TheFn = unsafe { library.get(b"RtlGetNtVersionNumbers\0").map(|sym| *sym)? };
+    let (mut major, mut minor, mut build) = (0, 0, 0);
+    unsafe { func(&mut major, &mut minor, &mut build) };
+    Ok((major, minor, build))
+}
+
 pub(crate) const fn win_guid_to_u128(guid: &GUID) -> u128 {
     let data4_u64 = u64::from_be_bytes(guid.data4);
     ((guid.data1 as u128) << 96) | ((guid.data2 as u128) << 80) | ((guid.data3 as u128) << 64) | (data4_u64 as u128)