diff options
| author | Matthijs Lavrijsen <mattiwatti@gmail.com> | 2023-03-26 19:10:14 +0200 |
|---|---|---|
| committer | Matthijs Lavrijsen <mattiwatti@gmail.com> | 2023-03-26 19:10:14 +0200 |
| commit | e588a7d948ecbca89005d4acd98231f9cf934868 (patch) | |
| tree | ed30f9fb632e14b05df3b8e7e91b00955352211b /Application | |
| parent | 9c35789cf813bb80fcc4be8475ccd9cd149ddcb3 (diff) | |
Loader: check entry descriptions to determine whether they are Windows
Diffstat (limited to 'Application')
| -rw-r--r-- | Application/Loader/Loader.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/Application/Loader/Loader.c b/Application/Loader/Loader.c index 61b296c..42bdfb1 100644 --- a/Application/Loader/Loader.c +++ b/Application/Loader/Loader.c @@ -375,15 +375,17 @@ TryBootOptionsInOrder( // // Filter out non-Windows boot entries. - // Apply some heuristics based on the device path, which must end in "bootmgfw.efi" or "bootx64.efi". - // In the latter case we may get false positives, but for some types of boots (WinPE, Windows To Go, - // and that VM product from Larry Ellison that still can't emulate NVRAM properly), the name will - // always be bootx64.efi, so this can't be avoided. - // - // For the common case, a simpler way would have been to check if the description is "Windows Boot Manager", - // but it turns out that we need the full path anyway to LoadImage the file with BootPolicy = TRUE. + // Check the description first as "Windows Boot Manager" entries are obviously going to boot Windows. + // However the inverse is not true, i.e. not all entries that boot Windows will have this description. // BOOLEAN MaybeWindows = FALSE; + if (BootOptions[Index].Description != NULL && + StrStr(BootOptions[Index].Description, L"Windows Boot Manager") != NULL) + { + MaybeWindows = TRUE; + } + + // We need the full path to LoadImage the file with BootPolicy = TRUE. UINTN FileSize; VOID* FileBuffer = EfiBootManagerGetLoadOptionBuffer(BootOptions[Index].FilePath, &FullPath, &FileSize); if (FileBuffer != NULL) @@ -394,9 +396,14 @@ TryBootOptionsInOrder( if (FullPath == NULL) FullPath = BootOptions[Index].FilePath; - // Get the text representation of the device path and check it for our suspects + // Get the text representation of the device path CHAR16* ConvertedPath = ConvertDevicePathToText(FullPath, FALSE, FALSE); - if (ConvertedPath != NULL && + + // If this is not a named "Windows Boot Manager" entry, apply some heuristics based on the device path, + // which must end in "bootmgfw.efi" or "bootx64.efi". In the latter case we may get false positives, + // but for some types of boots the filename will always be bootx64.efi, so this can't be avoided. + if (!MaybeWindows && + ConvertedPath != NULL && (StrStr(ConvertedPath, L"bootmgfw.efi") != NULL || StrStr(ConvertedPath, L"BOOTMGFW.EFI") != NULL || StrStr(ConvertedPath, L"bootx64.efi") != NULL || StrStr(ConvertedPath, L"BOOTX64.EFI") != NULL)) { |