PHP 5.x/7.x polyfill for mcrypt extension.

With Composer:

composer require phpseclib/mcrypt_compat

• rijndael-128
• rijndael-192
• rijndael-256
• des
• blowfish
• rc2
• tripledes
• arcfour

• cast-128
• gost
• cast-256
• loki97
• saferplus
• wake
• blowfish-compat
• serpent
• xtea
• enigma

• cbc
• ncfb
• ctr
• ecb
• nofb
• stream

Although ncfb and nofb are supported cfb and ofb are not. Further, mcrypt_compat's ncfb implementation has some incompatibles with mcrypt's implementation where mcrypt_generic and mdecrypt_generic are concerned. The unit tests elaborate.