The name 'Pink' stands for Password-Tink. It is a Android library that extends the popular crypto library build by Google engineers to support password based encryption and decryption. It uses the official Argon2 source with JNI to derive a key from the password.
This library was created for and is an elementary part of my file encryption app Truvark (Play Store).
NOTE: I am NOT a cryptography expert. The Argon2 implementation is using code from Argon2Kt and the interaction with Tink is based on this issue from their repository.
Example for creating a new KeysetHandle, encrypting it with a password and finally exporting the
encrypted Keyset to store it.
// Generate a new KeysetHandle as you know it from Tink
StreamingAeadConfig.register()
val aesKeyTemplate = KeyTemplates.get("AES256_GCM_HKDF_4KB")
val keysetHandle = KeysetHandle.generateNew(aesKeyTemplate)
// Encrypt it with a password
val passwordBytes = TODO("Password as ByteArray")
val encryptedKeyset = keysetHandle.encryptWithPassword(passwordBytes)
// Export the encrypted Keyset
val encryptedKeysetString = encryptedKeyset.exportAsString()Example for importing an encrypted Keyset and decrypting it with the password to obtain a
KeysetHandle.
// Register Tink if not done earlier. Get the encryptedKeysetString and password
StreamingAeadConfig.register()
val encryptedKeysetString = TODO("The exported encrypted Keyset String, see above")
val passwordBytes = TODO("Password as ByteArray")
// Import the stored String
val encryptedKeyset = PasswordEncryptedKeyset.importFromString(encryptedKeysetString)
// Decrypt the Keyset
val keysetHandle = encryptedKeyset.decryptWithPassword(passwordBytes)
// Use the KeysetHandle as you know it from Tink, e.g.
val streamingAead = keysetHandle.getPrimitive(StreamingAead::class.java)