mcrypt_decrypt Decrypts crypttext with given parameters &reftitle.description; stringmcrypt_decrypt stringcipher stringkey stringdata stringmode stringiv Decrypts the data and returns the unencrypted data. &reftitle.parameters; cipher &mcrypt.parameter.cipher; key The key with which the data was encrypted. If the provided key size is not supported by the cipher, the function will emit a warning and return &false; data The data that will be decrypted with the given cipher and mode. If the size of the data is not n * blocksize, the data will be padded with '\0'. mode &mcrypt.parameter.mode; iv &mcrypt.parameter.iv.strict; &reftitle.returnvalues; Returns the decrypted data as a string &return.falseforfailure;. &reftitle.changelog; &Version; &Description; 5.6.0 Invalid key and iv sizes are no longer accepted. mcrypt_decrypt will now throw a warning and return &false; if the inputs are invalid. Previously keys and IVs were padded with '\0' bytes to the next valid size. &reftitle.seealso; mcrypt_encrypt