What is the best encryption library in C/C++?

Question

What is the best encryption library in C/C++ In terms of:

• entropy
• quality
• ease of use
• readability
• portability
• performance

What's your favorite and why do you like it?

Answer 1

We've used OpenSSL with good success. Portable, standards compliant and easy to use.

Answer 2

I'm gonna have to go with LibTomCrypt. It's often overlooked for OpenSSL, but TomCrypt is just so lightweight and simple. As for quality, TomCrypt is widely accepted as top-quality encryption. Also, it's license is public domain which avoids the attribution hassle for your documentation that BSD licenses give you when writing commercial software.

Answer 3

My favorite is GNU's library:

[Libgcrypt][1]

It's performance is good, and its used EVERYWHERE so it's very well tested.

Answer 4

The C++ version isn't out yet but goolge KeyCzar http://code.google.com/p/keyczar/ might be worth looking at. Whatever you feel about their business they do have a lot of smart programmers working for them.

Answer 5

Crypto++ seem to have a good reputation

Answer 6

I've used CryptoPP in the past (http://www.cryptopp.com/) and although its API style and programming paradigms take a little getting used to, I liked it in the end. It provides a wide range of symmetric and asymmetric algorithms with much flexibility. Documentation is so-so, the API docs are there but there's little 'high-level' overview and simple sample code. I ended up puzzling together pieces of code from around the net. It was easy to integrate into my project (linked statically). I'm using MSVC - 2003 when I started using it, now switched to 2008. It's portable across several platforms (check out the website). I've always used the default RNG, don't know which one that is.

Answer 7

GPGme. Simple to use and compatible with the OpenPGP format