yaSSL Embedded SSL Library

The yaSSL software package is a fast, open source, dual licensed implementation of SSL (SSL 3, TLS 1.0, and TLS 1.1) built in C++.

It includes SSL client libraries and an SSL server implementation. yaSSL supports multiple API's, including those defined by SSL and TLS.  yaSSL also includes an OpenSSL compatibility interface.

NOTE: If you don’t need to work with C++, we recommend using wolfSSL instead.

Contact us to get the latest open source GPLv2 version of yaSSL.

Version: 2.4.2
Release Date: 9/22/2016
View ChangeLog


  • Up to TLS 1.1 and DTLS 1.0
  • Full client and server support
  • Simple API
  • PEM and DER certificate support
  • Support available


yaSSL is dual licensed under both the GPLv2 as well as a standard commercial license.  yaSSL also contains the FLOSS exception.

FOSS Exception for yaSSL: If you are developing Free and Open Source Software under a FOSS license other than GPL, then our FOSS exception should apply. Our FOSS exception generally means that our software can be used with certain FOSS licenses without causing the entire derivative work to be subject to the GPL. More information can be found on our license page.

Supported Operating Environments:

  • Win32/64, Linux, Mac OS X, Solaris, ThreadX, VxWorks, FreeBSD, NetBSD, OpenBSD, OpenWRT, iPhone (iOS), Nintendo Wii and Gamecube through DevKitPro, QNX, MontaVista, OpenCL, CUDA, NonStop, Tron/itron/microitron


  • SSL version 3 and TLS versions 1.0 and 1.1 (client and server)
  • Runtime memory usage between 5-50kb
  • DTLS support (client and server)
  • OpenSSL compatibility layer ( Read More )
  • MySQL integration
  • zlib compression support
  • stunnel integration, see download page to get version of stunnel with wolfSSL
  • Multiple Hashing Functions: MD2, MD4, MD5, SHA-1, SHA-2, RIPEMD
  • Block and Stream Ciphers: DES, 3DES, AES, ARC4, RABBIT, HC-128
  • Public Key Options: RSA, DSS, DH
  • Password-based Key Derivation: HMAC, PBKDF2, PKCS#5
  • Simple API
  • Interchangeable crypto and certificate libraries
  • PEM and DER certificate support
  • Intel AES-NI support
  • Client authentication support
  • Sniffer support

Licensing and Ordering:

yaSSL is dual licensed under both the GPLv2 and commercial licensing.  For more information, refer to our license page or contact us.