bcrypt password hash C library
This library is a simple wrapper providing a convenient reentrant interface for the bcrypt password hashing algorithm implementation as provided by Solar Designer at http://www.openwall.com/crypt/. An exact copy of that source code is included in the crypt_blowfish subdirectory.
The provided C interface is inspired in the bcrypt Python module that can be found at http://code.google.com/p/py-bcrypt/, and consists of a function to generate salts with the characteristic work factor parameter, one to generate password hashes which can also used to verify passwords and one designed specifically to verify passwords and avoid timing attacks. Please check the header bcrypt.h. It contains the prototypes and lots of comments with examples.
All this code is released to the public domain under the terms of CC0. See the COPYING file for the legal text.