Class: Hide::AE

Inherits:
Object
  • Object
show all
Defined in:
lib/hide/ae.rb

Overview

‘AE` implements authenticated encryption API based on AES-256

Class Method Summary collapse

Class Method Details

.decrypt(data, key, salt, iter, iv, auth_tag, auth_data = "", key_length = 32) ⇒ Object

Decrypts an encrypted datastream with authenticity verification check

[//]: # (TODO: investigate :reek:FeatureEnvy)

Returns the decrypted data



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# File 'lib/hide/ae.rb', line 30

def decrypt(
  data, key, salt, iter, iv, auth_tag, auth_data = "", key_length = 32
)
  decipher = OpenSSL::Cipher.new "aes-256-gcm"
  decipher.decrypt
  decipher.key =
    OpenSSL::PKCS5.pbkdf2_hmac_sha1(key, salt, iter, key_length)
  decipher.iv = iv
  decipher.auth_tag = auth_tag
  decipher.auth_data = auth_data
  decipher.update(data) + decipher.final
rescue OpenSSL::Cipher::CipherError
  raise ArgumentError, "Authentication failed"
end

.encrypt(data, key, salt, iter, iv = SecureRandom.random_bytes(12), auth_data = "", key_length = 32) ⇒ Object

Encrypts a data stream with an authenticity tag for reliable decryption

Returns a hash containing encrypted data, IV and authentication tag



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# File 'lib/hide/ae.rb', line 8

def encrypt(
  data, key, salt, iter, iv = SecureRandom.random_bytes(12),
  auth_data = "", key_length = 32
)
  cipher = OpenSSL::Cipher.new "aes-256-gcm"
  cipher.encrypt
  cipher.key =
    OpenSSL::PKCS5.pbkdf2_hmac_sha1(key, salt, iter, key_length)
  cipher.iv = iv
  cipher.auth_data = auth_data
  {
    data: cipher.update(data) + cipher.final,
    iv: iv,
    auth_tag: cipher.auth_tag
  }
end