BitLocker is a full-disk encryption feature available in recent Windows versions (Vista, 7, 8.1 and 10) Pro and Enterprise. BitCracker is a mono-GPU password cracking tool for memory units encrypted with the password authentication mode of BitLocker (see picture below).
Our attack has been tested on several memory units encrypted with BitLocker running on Windows 7, Window 8.1 and Windows 10 (both compatible and non-compatible mode). Here we present two implementations: CUDA and OpenCL.
For CUDA implementation, you need at least CUDA 7.5 and an NVIDIA GPU with minimum cc3.5 (i.e. Kepler arch)
Use the build.sh script to build 3 executables:
BitCracker OpenCL version
The executables are stored in the build directory.
Before starting the attack, you need to run bitcracker_hash to extract the hash from the encrypted memory unit.
> ./build/bitcracker_hash -h
Usage: ./build/bitcracker_hash -i <Encrypted memory unit> -o <output file>
-h, --help Show this help -i, --image Path of memory unit encrypted with BitLocker -o, --outfile Output file
The extracted hash is fully compatible with the John The Ripper format (see next Section).
Then you can use the output hash file to run the BitCracker attack.
> ./build/bitcracker_cuda -h Usage: ./build/bitcracker_cuda -f <hash_file> -d <dictionary_file> Options: -h, --help Show this help -f, --hashfile Path to your input hash file (HashExtractor output) -s, --strict Strict check (use only in case of false positives) -d, --dictionary Path to dictionary or alphabet file -g, --gpu GPU device number -t, --passthread Set the number of password per thread threads -b, --blocks Set the number of blocks
Note: In case of false positives you can use the -s option, that is a more restrictive check on the correctness of the final result. Altough this check is empirically verified and it works with the images of this repo encrypted with Windows 7, 8.1 and 10, we can't guarantee that it doesn't lead to false negatives. Use -s option only if BitCracker returns several false positives.
In the the run_test.sh script there are several attack examples using the encrypted images provided in this repo:
Here we report best performance of BitCracker implementations tested on different GPUs
GPU Acronim | GPU | Arch | CC | # SM | Clock | CUDA
GFT | GeForce Titan | Kepler | 3.5 | 14 | 835 | 7.0
GTK80 | Tesla K80 | Kepler | 3.5 | 13 | 875 | 7.5
GFTX | GeForce Titan X | Maxwell | 5.2 | 24 | 1001 | 7.5
GTP100 | Telsa P100 | Pascal | 6.1 | 56 | 1328 | 8.0
AMDM | Radedon Malta | - | - | - | - | -
Version | GPU | -t | -b | Passwords x kernel | Passwords/sec | Hash/sec
CUDA | GFT | 8 | 13 | 106.496 | 303 | 635 MH/s
CUDA | GTK80 | 8 | 14 | 114.688 | 370 | 775 MH/s
CUDA | GFTX | 8 | 24 | 106.608 | 933 | 1.957 MH/s
CUDA | GTP100 | 8 | 56 | 458.752 | 1.363 | 2.858 MH/s
OpenCL | AMDM | 32 | 64 | 524.288 | 241 | 505 MH/s
OpenCL | GFTX | 8 | 24 | 196.608 | 884 | 1.853 MH/s
John The Ripper
We released the OpenCL version as a plugin of the John The Ripper (bleeding jumbo) suite:
In the next relese: