AeroGear - Crypto.md

AeroGear Crypto API

Note: This document is a working progress

Authors

• Bruno Oliveira
• put your pretty name here

Goals

• User friendly interface for non crypto experts
• Advanced developers can make use of the pure crypto provider implementation.

Supported Algorithms

• https://issues.jboss.org/browse/AGSEC-114

Scenarios

Note: For all scenarios the authentication process was intentionally ignored.

• A logged in user wants to store sensitive data on mobile

Another alternative (We need to think about the entropy, would be nice to have something coming from the server)

• The mobile device goes offline but the sensitive data must be protected

• The data must be backed up on the server, but passwords can't be exposed

• The application was installed into another device and the keys must be revoked on the server

[Under development]

• User wants to configure for how long the keys will be considered valid

[Under development]

• Device was stolen and data must be destroyed

[Under development]

JavaScript

Dependencies

• sjcl with wrappers for basic functionalities like: encrypt, decrypt, password salting and key pair generation.

Implementation details

• The size of sjcl library is still a concern (28K)

• Crypto bits were built in a separate module so it may be included/excluded in a custom build.

• The project will be developed under AeroGear.js repository (aerogear-attic/aerogear-js#57)

API (draft 0)

• Password based key derivation support (PBKDF2)

    myEncryptedPassword = AeroGear.password("strong");
  

• Symmetric encryption support (GCM)

  • Encryption:

      var options = {
          IV: superRandomInitializationVector,
          AAD: "whateverAuthenticatedData",
          key: generatedKey,
          data: "My bonnie lies over the ocean"
      };
      
      var cipherText = AeroGear.encrypt( options );
    

  • Decryption:

      var options = {
          IV: superRandomInitializationVector,
          AAD: "whateverAuthenticatedData",
          key: generatedKey,
          data: cipherText
      };
      AeroGear.decrypt( options );
    

• Message authentication support (GMAC, HMAC)

[Under development]

Note: The implementations below are currently under discussion at aerogear-attic/aerogear-js#62

• Hashing support (SHA-256, SHA-512)

    digest = AeroGear.crypto.hash("some message");
  

• Asymmetric encryption support (ECC)

    var hex = sjcl.codec.hex,
        keyPair = new AeroGear.crypto.KeyPair(),
        cipherText, plainText,
        options = {
            IV: superRandomInitializationVector,
            AAD: "whateverAuthenticatedData",
            key: keyPair.publicKey,
            data: ""My bonnie lies over the ocean"
        };
    cipherText = AeroGear.crypto.encrypt( options );
    options.key = keyPair.privateKey;
    options.data = cipherText;
    plainText = AeroGear.crypto.decrypt( options );
  

• Digital signatures support (ECDSA)

    var validation,
        options = {
            keys: sjcl.ecc.ecdsa.generateKeys(192),
            message: "My bonnie lies over the ocean"
        };
    options.signature = AeroGear.crypto.sign( options );
    validation = AeroGear.crypto.verify( options );
  

Android

Dependencies

• Spongy Castle with wrappers for basic functionalities like: encrypt, decrypt, password salting and key pair generation.

Implementation details

• The bouncycastle "provided" in Android doesn't have ECDH that's the reason why Spongy Castle was chosen.

• aerogear-crypto-java will be the main repository to provide a crypto API for Android and the Java server.

API (draft 0)

Note: The implementations below are currently under discussion at https://github.com/aerogear/aerogear-crypto-java/tree/refactoring

• Password based key derivation support (PBKDF2)

    Pbkdf2 pbkdf2 = AeroGearCrypto.pbkdf2();
    byte[] rawPassword = pbkdf2.encrypt(PASSWORD);
  

• Symmetric encryption support (GCM)

  • Encryption:

      CryptoBox cryptoBox = new CryptoBox(new PrivateKey(SOME_SECRET_KEY));
      final byte[] IV = new Random().randomBytes(); 
      final byte[] message = "My bonnie lies over the ocean".getBytes();
      final byte[] ciphertext = cryptoBox.encrypt(IV, message);
    

  • Decryption:

      CryptoBox pandora = new CryptoBox(new PrivateKey(SOME_SECRET_KEY));
      final byte[] message = pandora.decrypt(IV, ciphertext);
    

• Message authentication support (GMAC, HMAC)

[Under development]

• Hashing support (SHA-256, SHA-512)

[Under development]

• Asymmetric encryption support (ECC)

    KeyPair keyPair = new KeyPair();
    KeyPair keyPairPandora = new KeyPair();
  
    CryptoBox cryptoBox = new CryptoBox(keyPair.getPrivateKey(), keyPairPandora.getPublicKey());
    final byte[] IV = new Random().randomBytes();
    final byte[] message = "My bonnie lies over the ocean".getBytes();
    final byte[] ciphertext = cryptoBox.encrypt(IV, message);
  
    CryptoBox pandora = new CryptoBox(keyPairPandora.getPrivateKey(), keyPair.getPublicKey());
    final byte[] message = pandora.decrypt(IV, ciphertext);
  

• Digital signatures support (ECDSA)

[Under development]

iOS

Dependencies

[TBD] - http://oksoclap.com/p/iOS_Meeting_(Security)

• Common Crypto

Implementation details

[TBD]

API (draft 0)

• Password based key derivation support (PBKDF2)

[Under development]

• Symmetric encryption support (GCM)

[Under development]

• Message authentication support (GMAC, HMAC)

[Under development]

• Hashing support (SHA-256, SHA-512)

[Under development]

• Asymmetric encryption support (ECC)

[Under development]

• Digital signatures support (ECDSA)

[Under development]