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This release contains a patch for OpenSSL 1.0.2g to support the Supersingular Isogeny-based Diffie-Hellman (SIDH) key exchange [1], using the implementation of Microsoft Research [2]. This scheme provides approximately 128 bits of quantum security and 192 bits of classical security.

• The library specifies four ciphersuites* SIDH-ECDSA-AES128-GCM-SHA256* SIDH-RSA-AES128-GCM-SHA256* SIDH-ECDHE-ECDSA-AES128-GCM-SHA256* SIDH-ECDHE-RSA-AES128-GCM-SHA256The first two consist of a SIDH key exchange, as described in [1], authentication based on ECDSA or RSA digital signatures, authenticated encryption (with associated data) (AEAD) based on AES-128 in GCM (Galois Counter Mode); and key derivation and hashing based on SHA-256. The last two offer hybrid ciphersuites that are as above, except the key exchange includes both SIDH and ECDH key exchange; the pre-master secret is the concatenation of the ECDH shared secret and the SIDH shared secret. All these ciphersuites require TLSv1.2 because of the use of AES-GCM.REFERENCES----------[1] Craig Costello, Patrick Longa, and Michael Naehrig (Microsoft Research). "Efficient algorithms for supersingular isogeny Diffe-Hellman." https://eprint.iacr.org/2016/413.pdf.[2] http://research.microsoft.com/en-us/projects/sidh/[3] https://openssl.org/source/old/1.0.2/openssl-1.0.2g.tar.gz

Files

Status: Live This download is still available on microsoft.com. The downloads below will come directly from the Microsoft Download Center.

File	Size
sidh-for-openssl-1.0.2g.patch SHA1: 249714180e5f0d11a47aae284439f88ffd824b95	80 KB

File sizes and hashes are retrieved from the Wayback Machine’s indexes. They may not match the latest versions of files hosted on Microsoft servers.

• • This patch is for OpenSSL 1.0.2g – it is cross-platform to the OS (supports Windows, Unix, Mac)

• • Click Download and follow the instructions.