Class: Sekrit::Decoder

Inherits:
Object show all
Defined in:
lib/sekrit/decoder.rb

Instance Method Summary collapse

Constructor Details

#initialize(password: String) ⇒ Decoder

Returns a new instance of Decoder.



9
10
11
 
# File 'lib/sekrit/decoder.rb', line 9

def initialize(password: String)
  @password = password
end

Instance Method Details

#decode(string: String) ⇒ Object

bsarrazin

July 20th, 2019

Stolen from Fastlane, as I am not an expert on encryption/decryption. If you have experience and want to help, please submit a pull request :)

> We encrypt with MD5 because that was the most common default value in older fastlane versions which used the local OpenSSL installation > A more secure key and IV generation is needed in the future, IV should be randomly generated and provided unencrypted > salt should be randomly generated and provided unencrypted (like in the current implementation) > key should be generated with OpenSSL::KDF::pbkdf2_hmac with properly chosen parameters > Short explanation about salt and IV: stackoverflow.com/a/1950674/6324550



22
23
24
25
26
27
28
29
30
31
32
 
# File 'lib/sekrit/decoder.rb', line 22

def decode(string: String)
  data = Base64.decode64(string)
  salt = data[8..15]
  data = data[16..-1]

  decipher = OpenSSL::Cipher.new('AES-256-CBC')
  decipher.decrypt
  decipher.pkcs5_keyivgen(@password, salt, 1, "MD5")

  decipher.update(data) + decipher.final
end