Encrypted

Ruby on Rails gem for encryption and decryption with Rijndael algorithm and CBC.

Key size options: 128, 192 and 256 bits Block size options: 128, 192 and 256 bits

AES is version of Rijndael with 128 bits block size. Hence, to encrypt/decrypt with AES standard choose any key size but 128 bits block size.

Installation

Add this line to your application's Gemfile:

gem 'encrypted'

And then execute:

$ bundle

Or install it yourself as:

$ gem install encrypted

Usage

Mode needs to be supplied when instantiating Encrypted::Ciph. Mode consists of desirable key length and block length in "keysize-blocksize" format. "256-128" implies key size of 256 bits and block size of 128 bits.

Encryption

    encrypt_this = "This is seriously confidential message."
    cipher = Encrypted::Ciph.new("256-256")
    key = "xvxvxvxxvxvxvxvxvxvxvxvxvxvxvxvx" # 256 bits / 8 = 32 bytes
    iv = "nmnmnmnmnmnmnmnmnmnmjkjkhjhjhjgh"  # 256 bits / 8 = 32 bytes
    cipher.key = key
    cipher.iv = iv
    encrypted_text = cipher.encrypt(encrypt_this)

Decryption

    decrypt_this = encrypted_text               #from above
    decipher = Encrypted::Ciph.new("256-256")
    cipher.key = "xvxvxvxxvxvxvxvxvxvxvxvxvxvxvxvx"     #key used above to encrypt
    cipher.iv = "nmnmnmnmnmnmnmnmnmnmjkjkhjhjhjgh"      #initialization vector used above
    decrypted_text = cipher.decrypt(decrypt_this)

"decrypted_text => 'This is some seriously confidential message.'"

Key and IV generation helper

To automatically generate and assign right size of random key and iv bytes while encrypting.

    encrypt_this = "This is seriously confidential message. Let me generate stuff for ya."
    cipher = Encrypted::Ciph.new("256-128")
    key = cipher.generate_key                    # Sets and returns 32 bytes long string
    iv = cipher.generate_iv                      # Sets and returns 16 bytes long string
    encrypted_text = cipher.encrypt(encrypt_this)
    

Contributing

1. Fork it ( https://github.com/getaasciesh/encrypted/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request