Botan home page

botan mirror on github

Strictly speaking, Botan is a general-purpose crypto library, but has a TLS implementation. Source is kept in Monotone, but there is a Github mirror. Botan has had continuous development since 2001. Is it safe to use in a commercial product? Good question.

It builds on Unix/POSIX and Microsoft Windows. There are instructions for both iOS and Android builds referenced in the documentation.





LibreSSL is a fork of OpenSSL done by the OpenBSD folks as a security-focused rewrite. There is a new library coming called ressl, for reimagined SSL.




Secure Channel or Schannel is the name of Microsoft’s SSL implementation, implemented as an SSP in their Security Support Provider Interface.


Secure Transport

Secure Transport is Darwin/Mac OS X’s name for SSL. Modern features are only supported in Mac OS X 10.8 or later. Also annoyingly, you must put certificates in the Keychain instead of bundling them with your program. But it’s open source under the APSL 2.0 license.

Secure Transport Reference



PolarSSL is now a part of ARM - and Hacker News comments


Wikipedia - Comparison of TLS implementations

Note to self - don’t allow SSL renegotiation. Re: SSL renegotiation

OpenSSL Cookbook

Network Security with OpenSSL

Cryptographic Key Length Recommendation

Compare SSL libraries

On the Uses of Cryptography in Industry

Security Now podcast, episode 449

Stuff from Daniel Bernstein

Things that use Curve25519

A state-of-the-art Diffie-Hellman function

Ed25519: high-speed high-security signatures

Things that use Ed25519