BIKE-1 - Additional implementation of "BIKE: Bit Flipping Key Encapsulation".

【！before you read，the developing branch is the latest branch, please switch branches to view the codes！】

This package is an "additional optimized" implementation of the Round-2 variant of BIKE-1.

BIKE is a submission to the Post-Quantum Cryptography Standardization project http://csrc.nist.gov/projects/post-quantum-cryptography.

The official BIKE website is: https://bikesuite.org

This package offers two constant time implementations of Round-2 BIKE-1.

• A portable implementation that requires libcrypto.a (e.g., of OpenSSL) for AES256 and SHA384.
• An x86_64 optimized implementation with AVX2 or AVX512.

The optimizations in this package are based on the papers:

• Nir Drucker, Shay Gueron, "A Toolbox for Software Optimization of QC-MDPC Code-Based Cryptosystems." Journal of Cryptographic Engineering, January 2019, 1–17 https://doi.org/10.1007/s13389-018-00200-4.

• Chou, T.: QcBits: Constant-Time Small-Key Code-Based Cryptography. In: Gier-lichs, B., Poschmann, A.Y. (eds.) Cryptographic Hardware and Embedded Systems– CHES 2016. pp. 280–300. Springer Berlin Heidelberg, Berlin, Heidelberg (2016)

• Guimarães, Antonio, Diego F Aranha, and Edson Borin. 2019. “Optimized Implementation of QC-MDPC Code-Based Cryptography.” Concurrency and Computation: Practice and Experience 31 (18): e5089. https://doi.org/10.1002/cpe.5089.

The decoder (in decoder/decoder.c) algorithm is the Black-Gray decoder included in the early submission of CAKE (due to N. Sandrier and R. Misoczki).

The analysis for the constant-time implementation is given in: Drucker, Nir, Shay Gueron, and Dusan Kostic. 2019. “On Constant-Time QC-MDPC Decoding with Negligible Failure Rate.” Cryptology ePrint Archive, 2019. https://eprint.iacr.org/2019/1289.

The BG decoder was modified into BGF in Drucker, Nir, Shay Gueron, and Dusan Kostic. 2019. “QC-MDPC decoders with several shades of gray.” Cryptology EPrint Archive, 2019.

The code is due to Nir Drucker, Shay Gueron, and Dusan Kostic.

BUILD

To compile: make

Default is BIKE-1 (Round-2 variant) at Level-1 (64-bit quantum security) without AVX2/512 support (portable). This compilation assumes that AES_NI, POPCNT, and PCLMULQDQ instructions are available, for other platforms use USE_OPENSSL=1.

Additional compilation flags:

• USE_NIST_RAND - Using the RDBG of NIST and generate the KATs.
• USE_OPENSSL - Use OpenSSL for AES/SHA and GF2X multiplication. OpenSSL must be installed on the platform.
• OPENSSL_DIR - Set the path of the OpenSSL include/lib directories.
• FIXED_SEED - Using a fixed seed, for debug purposes.
• RDTSC - Measure time in cycles rather than in mseconds.
• VERBOSE - Add verbose (level:1-4 default:1).
• NUM_OF_TESTS - Set the number of tests to be run.
• AVX2 - Compile with AVX2 support (to compile use GCC).
• AVX512 - Compile with AVX512 support (to compile use GCC).
• LEVEL - Security level (1/3/5).
• ASAN/TSAN - Enable the associated clang sanitizer

To clean: make clean.

Note: a "clean" is required prior to compilation with modified flags.

Example: make AVX2=1 USE_OPENSSL=1 VERBOSE=2

The package was compiled and tested with gcc (version 4.8.0 or above) in 64-bit mode. Tests were run on a Linux (Ubuntu 16.04.3 LTS) OS. Compilation on other platforms may require some adjustments.