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Crypt::RC6 - Crypt::CBC compliant RC6 block cipher encryption module


    use Crypt::RC6;
    my $cipher = new Crypt::RC6 $key;

    my $ciphertext = $cipher->encrypt($plaintext);
    my $plaintext = $cipher->decrypt($ciphertext);


From THE RC6 BLOCK CIPHER, by Rivest, Robshaw, Sidney, and Yin...

"RC6 is an evolutionary improvement of RC5, designed to meet the requirements of the Advanced Encryption Standard (AES). Like RC5, RC6 makes essential use of data-dependent rotations. New features of RC6 include the use of four working registers instead of two, and the inclusion of integer multiplication as an additional primitive operation. The use of multiplication greatly increases the diffusion achieved per round, allowing for greater security, fewer rounds, and increased throughput."

This implementation requires the use of a 16-, 24-, or 32-byte key and 16-byte blocks for encryption/decryption. Twenty rounds are performed.



John Hughes (

I am indebted to Marc Lehmann, the author of the Crypt::Twofish2 module, as I used his code as a guide.