Introduction¶

There are several extensions & libraries that provide cryptography primitives for PHP:

• the legacy mcrypt extension
• the OpenSSL extension
• the libsodium extension
• the tomcrypt extension
• probably others I don’t know about…

Although these extensions all provide roughtly the same features, the programmatic interface they expose is very different.

Also, very few of those extensions support on-the-fly encryption/decryption.

Cryptal was created to work around these issues by providing a unified interface & transparent support for on-the-fly encryption/decryption using stream filters.