TLS/SSL and crypto library

darktable is an open source photography workflow application and raw developer

LibTomCrypt is a fairly comprehensive, modular and portable cryptographic toolkit that provides developers with a vast array of well known published block ciphers, one-way hash functions, chaining …

LibTomMath is a free open source portable number theoretic multiple-precision integer library written entirely in C.

A reference implementation of the Russian GOST crypto algorithms for OpenSSL

TomsFastMath is a fast public domain, open source, large integer arithmetic library written in portable ISO C.

Cryptodev-linux is a Linux-kernel device that allows user-space access to hardware cryptographic accelerators.

Frexx C preprocessor

OpenSSL provider using Windows Cryptography API: Next Generation

PKCS11 Engine for OpenSSL