OpenSSL - OpenSSL is a free and open source software cryptography library that implements both the Secure Sockets Layer (SSL) and the Transport Layer Security (TLS) protocols, which are primarily used to provide secure communications between web browsers and …
OpenXPKI - OpenXPKI is a software stack that provides all necessary components to manage keys and certificates...
GnuTLS - GnuTLS (the GNU Transport Layer Security Library) is a free software implementation of the SSL, TLS...
Dogtag PKI - The Dogtag Certificate System is an enterprise-class open source Certificate Authority (CA).
mbed TLS - mbed TLS . PolarSSL . Easy to use SSL library in C . Embedded . Open source . Readable source code . Tested . Well-documented ✓
Vault by HashiCorp - Tool for managing secrets