class OpenSSL::Cipher

• OpenSSL::Cipher
• Reference
• Object

Overview

A class which can be used to encrypt and decrypt data using a specified cipher.

NOTE The ciphers available to an application are determined by the linked version of the system SSL library. A comprehensive list of ciphers can be found in the OpenSSL Cipher documentation.

require "random/secure"
require "openssl"

def encrypt(data, key, iv)
  cipher = OpenSSL::Cipher.new("aes-256-cbc")
  cipher.encrypt
  cipher.key = key
  cipher.iv = iv

  io = IO::Memory.new
  io.write(cipher.update(data))
  io.write(cipher.final)
  io.rewind

  io.to_slice
end

def decrypt(data, key, iv)
  cipher = OpenSSL::Cipher.new("aes-256-cbc")
  cipher.decrypt
  cipher.key = key
  cipher.iv = iv

  io = IO::Memory.new
  io.write(cipher.update(data))
  io.write(cipher.final)
  io.rewind

  io.gets_to_end
end

key = Random::Secure.random_bytes(64) # You can also use OpenSSL::Cipher#random_key to do this same thing
iv = Random::Secure.random_bytes(32)  # You can also use OpenSSL::Cipher#random_iv to do this same thing

encrypted_data = encrypt("Encrypted", key, iv)    # => Bytes[95, 182, 21, 86, 193, 155, 149, 164, 82, 102, 171, 182, 56, 153, 223, 33]
decrypted_data = decrypt(encrypted_data, key, iv) # => "Encrypted"

Defined in:

Constructors

• .new(name)

Instance Method Summary

• #authenticated? : Bool
• #block_size : Int32
• #decrypt : Nil

  Sets this cipher to decryption mode.

• #encrypt : Nil

  Sets this cipher to encryption mode.

• #final : Bytes

  Outputs the decrypted or encrypted buffer.

• #finalize
• #iv=(iv)
• #iv_len : Int32

  How many bytes the iv should be.

• #key=(key)
• #key_len : Int32

  How many bytes the key should be.

• #name : String
• #padding=(pad : Bool)
• #random_iv

  Sets the iv using Random::Secure.

• #random_key

  Sets the key using Random::Secure.

• #reset

  Resets the encrypt/decrypt mode.

• #update(data)

  Add the data to be encrypted or decrypted to this cipher's buffer.

Constructor Detail

Instance Method Detail