There are three implementations of Streamlined NTRU Prime 4591761:
sntrup4591761.sage is the reference implementation.
ntruprime-20170815.tar.gz contains a portable C reference implementation (ref).
The same tarball also contains a Haswell-optimized implementation (avx). This implementation includes a very fast general-purpose integer-sorting library, avx/int32_sort.c, of independent interest.
We caution potential users that many details of Streamlined NTRU Prime were first published in May 2016 and still require careful security review. We have not limited ourselves to the minimum changes that would be required to switch to NTRU Prime from an existing version of the NTRU public-key cryptosystem; we have taken the opportunity to rethink and reoptimize all of the details of NTRU from an implementation and security perspective. We recommend NTRU Prime, but it is too early to recommend Streamlined NTRU Prime.
The C software was first published in August 2017 and requires careful security review beyond the review of the cryptosystem per se. See ref/README for specific warnings.
Version: This is version 2017.08.17 of the Software web page.