liboqs is a C library for quantum-resistant cryptographic algorithms. This branch of liboqs focuses on incorporating submissions to the NIST Post-Quantum Cryptography standardization project.

The Open Quantum Safe (OQS) project has the goal of developing and prototyping quantum-resistant cryptography.

liboqs is an open source C library for quantum-resistant cryptographic algorithms. liboqs provides:

• a common API for post-quantum key encapsulation mechanisms and digital signature schemes
• a collection of open source implementations of post-quantum cryptography algorithms
• a test harness and benchmarking routines

The OQS project also provides prototype integrations into application-level protocols to enable testing of quantum-resistant cryptography.

More information on OQS can be found on our website: https://openquantumsafe.org/.

This branch of liboqs aims to non-selectively incorporate submissions to the NIST Post-Quantum Cryptography project for the purposes of benchmarking and integration into a common API for liboqs-reliant applications.

This branch takes a "light touch" approach to incorporation:

• Source code from a NIST submission will be included ideally with no changes, in an "upstream" subdirectory.
• A thin wrapper will be written to provide the implementation using the liboqs API.
• The implementation will be added to the build process.
• To avoid namespace collisions between different algorithms, symbol renaming will be used on the compiled files.

For a list of algorithms included in nist-branch, see the datasheets in docs/algorithms.

liboqs nist-branch can be used in our fork of OpenSSL to prototype quantum-resistant TLS ciphersuites. See https://github.com/open-quantum-safe/openssl/tree/OQS-OpenSSL_1_0_2-stable.

liboqs is designed for prototyping and evaluating quantum-resistant cryptography. Security of proposed quantum-resistant algorithms may rapidly change as research advances, and may ultimately be completely insecure against either classical or quantum computers.

We believe that the NIST Post-Quantum Cryptography standardization project is currently the best avenue to identifying potentially quantum-resistant algorithms. liboqs does not intend to "pick winners", and we strongly recommend that applications and protocols rely on the outcomes of the NIST standardization project when deploying post-quantum cryptography.

We acknowledge that some parties may want to begin deploying post-quantum cryptography prior to the conclusion of the NIST standardization project. We strongly recommend that any attempts to do make use of so-called hybrid cryptography, in which post-quantum public-key algorithms are used alongside traditional public key algorithms (like RSA or elliptic curves) so that the solution is at least no less secure than existing traditional cryptography.

liboqs is provided "as is", without warranty of any kind. See LICENSE.txt for the full disclaimer.

In addition, implementations that we have included on this nist-branch of liboqs have received no quality control or vetting by OQS. THE NIST-BRANCH OF LIBOQS SHOULD BE USED EXCLUSIVELY FOR EXPERIMENTATION AND PROTOTYPING, AND SHOULD NEVER BE USED IN ANY PRODUCTION ENVIRONMENT OR TO PROTECT ANY SENSITIVE DATA.

• Algorithmic requirements:
  • Any algorithm accepted as a full and complete submission to round 1 of the NIST Post-Quantum Cryptography project is eligible for inclusion.
  • Algorithms whose security is considered effectively broken are not eligible for addition; see the Lifecycle section below for conditions on their removal.
  • KEMs can be IND-CPA or IND-CCA-secure, at any NIST security level.
  • Signature schemes can be EUF-CMA-secure, at any NIST security level.
• Targets:
  • Operating systems: The code must build on Linux and macOS.
  • Architecture: The code must build at least on x64. Targets are currently provided for x86 and x64. We plan to add an AVX2 target, and possibly others.
• Source code requirements:
  • The source code can be from the original submission, or can be an updated version.
  • License: Source code licensed under the MIT License, the BSD license, or in the public domain can be directly incorporated into the repository. GPL code will not be included in the repository, but a wrapper to the OQS API may be included, as well as a script that downloads and compiles in GPL code if the algorithm is requested at compile-time.
  • Code quality: Given the "light touch" philosophy of nist-branch, we have no requirements on source code quality, other than that it compile on the targets.

Contributions that meet the acceptance criteria above are gratefully welcomed. See CONTRIBUTING.md for details on contributing an implementation.

Release cycle: We aim to tag monthly snapshot of nist-branch, released around the end of each month. Plans for each individual snapshot release can be found on our Github projects board.

Algorithm deprecation: If an algorithm in nist-branch is found to be insecure in month $X$, a compile-time warning will be added in the tagged snapshot for month $X+1$, and it may be removed in month $X+2$.

Algorithm compatibility: Algorithm implementations on nist-branch may be updated at any time. This may cause changes in runtime or even a change in the message generation and processing. Thus, no guarantees are made for compatibility of messages exchange between different snapshots of nist-branch.

API stability: The public API of liboqs nist-branch is considered to be the functions in oqs/common.h, oqs/config.h, oqs/kem.h, oqs/rand.h, and oqs/sig.h. For the first few snapshot releases of nist-branch, this API should be considered in draft.

Binary compatibility: No guarantees are made for binary compatibility between different snapshots of nist-branch.

Builds are tested using the Travis continuous integration system on macOS 10.13.3 (clang 9.1.0) and Ubuntu 14.04.5 (gcc-7).

• Build status using Travis continuous integration system:

The dependencies for liboqs are OpenSSL and the Keccak Code Package (libkeccak). liboqs' build process will download and build libkeccak automatically. You must install OpenSSL following the instructions below.

You need to install the following packages:

sudo apt install gcc libssl-dev unzip xsltproc

You need to install the following packages using brew (or a package manager of your choice):

brew install openssl wget

To build, first clone or download the source from GitHub, then run Make.

git clone https://github.com/open-quantum-safe/liboqs.git
cd liboqs
git checkout nist-branch
make

If you wish to change the target architecture or disable certain algorithms, edit the first few lines of Makefile, then run:

make clean
make -j8

This will generate:

• liboqs.a: Static library
• liboqs.so: Shared library
• test_kem: Simple test harness for all enabled key encapsulation mechanisms
• test_sig: Simple test harness for all enabled key signature schemes
• kat_kem: Program that generates known answer test (KAT) values for all enabled key encapsulation mechanisms using the same mechanism as the NIST submission requirements, for checking against submitted KAT values
• kat_sig: Program that generates known answer test (KAT) values for all enabled signature schemes using the same mechanism as the NIST submission requirements, for checking against submitted KAT values
• speed_kem: Benchmarking program for key encapsulation mechanisms; see ./speed_kem --help for usage instructions
• speed_sig: Benchmarking program for signature schemes; see ./speed_sig --help for usage instructions
• example_kem: Minimal runnable example showing the usage of the KEM API
• example_sig: Minimal runnable example showing the usage of the signature API

You can specify the path for installation by overriding the PREFIX environment variable before running make install, for example:

PREFIX=/path/to/install make install

The directory docs/algorithms contains information about each algorithm available in this branch of liboqs.

If you have Doxygen installed (Linux: sudo apt install doxygen graphviz; macOS: brew install doxygen graphviz), you can build HTML documentation of the liboqs nist-branch API:

make docs

Then open docs/doxygen/html/index.html in your web browser.

liboqs is licensed under the MIT License; see LICENSE.txt for details.

liboqs includes some third party libraries or modules that may be licensed differently. All third-party code is contained in directories labelled upstream, and each such upstream directory contains a license file indicating the license that applies to code in that directory.

See https://github.com/XKCP/XKCP#under-which-license-is-the-xkcp-distributed for information on the licensing of the Keccak Code Package (libkecak).

The Open Quantum Safe project is lead by Douglas Stebila Michele Mosca at the University of Waterloo.

Contributors to this nist-branch of liboqs include:

• Nicholas Allen (Amazon Web Services)
• Maxime Anvari
• Eric Crockett (Amazon Web Services)
• Nir Drucker (Amazon Web Services)
• Vlad Gheorghiu (evolutionQ)
• Shay Gueron (Amazon Web Services)
• Christian Paquin (Microsoft Research)
• Tancrède Lepoint (SRI International)
• Shravan Mishra (University of Waterloo)
• Douglas Stebila (University of Waterloo)

nist-branch is based on the liboqs master branch, which includes additional contributors.

Upstream implementations are due to their original authors. See the algorithm datasheets in docs/algorithms for information about each upstream implementation.

Development of Open Quantum Safe has been supported in part by the Tutte Institute for Mathematics and Computing. Research projects which developed specific components of Open Quantum Safe have been supported by various research grants; see the source papers for funding acknowledgments.