Windows: Fix false-positive detection of Evil-Maid attack during creation process of hidden OS by excluding the configuration byte in the boot sector whose value changes depending on the content.

This commit is contained in:
Mounir IDRASSI 2016-10-05 13:13:26 +02:00
parent e5a9e9239b
commit 041bc9dc0b
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GPG key ID: DD0C382D5FCFB8FC
2 changed files with 0 additions and 5 deletions

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@ -623,9 +623,6 @@ void ComputeBootloaderFingerprint (byte *bootLoaderBuf, unsigned int bootLoaderS
WHIRLPOOL_add (bootLoaderBuf + TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH, (TC_BOOT_SECTOR_USER_CONFIG_OFFSET - (TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH)), &whirlpool);
sha512_hash (bootLoaderBuf + TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH, (TC_BOOT_SECTOR_USER_CONFIG_OFFSET - (TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH)), &sha2);
WHIRLPOOL_add (bootLoaderBuf + TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1, (TC_MAX_MBR_BOOT_CODE_SIZE - (TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1)), &whirlpool);
sha512_hash (bootLoaderBuf + TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1, (TC_MAX_MBR_BOOT_CODE_SIZE - (TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1)), &sha2);
WHIRLPOOL_add (bootLoaderBuf + TC_SECTOR_SIZE_BIOS, (bootLoaderSize - TC_SECTOR_SIZE_BIOS), &whirlpool);
sha512_hash (bootLoaderBuf + TC_SECTOR_SIZE_BIOS, (bootLoaderSize - TC_SECTOR_SIZE_BIOS), &sha2);

View file

@ -268,11 +268,9 @@ static void ComputeBootLoaderFingerprint(PDEVICE_OBJECT LowerDeviceObject, byte*
#endif
WHIRLPOOL_add (ioBuffer, TC_BOOT_SECTOR_PIM_VALUE_OFFSET, &whirlpool);
WHIRLPOOL_add (ioBuffer + TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH, (TC_BOOT_SECTOR_USER_CONFIG_OFFSET - (TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH)), &whirlpool);
WHIRLPOOL_add (ioBuffer + TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1, (TC_MAX_MBR_BOOT_CODE_SIZE - (TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1)), &whirlpool);
sha512_hash (ioBuffer, TC_BOOT_SECTOR_PIM_VALUE_OFFSET, &sha2);
sha512_hash (ioBuffer + TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH, (TC_BOOT_SECTOR_USER_CONFIG_OFFSET - (TC_BOOT_SECTOR_USER_MESSAGE_OFFSET + TC_BOOT_SECTOR_USER_MESSAGE_MAX_LENGTH)), &sha2);
sha512_hash (ioBuffer + TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1, (TC_MAX_MBR_BOOT_CODE_SIZE - (TC_BOOT_SECTOR_USER_CONFIG_OFFSET + 1)), &sha2);
// we has the reste of the bootloader, 512 bytes at a time
offset.QuadPart = TC_SECTOR_SIZE_BIOS;