songoku20/alice

Java AES encryption library

alice

Alice is a Java AES encryption library for working with byte arrays, files, and streams. Various key lengths, block modes, padding schemes, key deriviation functions, and Message Authentication Codes (MAC) are available. See the javadoc for more information.

Alice provides an easy wrapper around the javax.crypto cipher suite for symmetric key encryption. if a MAC algorithm is selected, additional Authenticated Encryption is performed using an encrypt-then-mac scheme.

Algorithms

• AES
• DES
• DESede (3DES)

Modes

• CBC (AES & DES & DESede)
• CTR (AES & DES & DESede)
• GCM (AES)

Padding

• NoPadding
• PKCS5Padding

Key Lengths (in bits)

• 64 (DES)
• 128 (AES)
• 192 (AES & DESede)
• 256 (AES)

Password Based Key Derivation Functions (PBKDF)

• None (use password as is, zero padded if necessary)
• SHA-{1, 224, 256, 384, 512} (hashes the password before use)
• PBKDF2WithHmacSHA{1, 256, 384, 512} (derives the key using a password-based key-derivation algorithm)

MAC Algorithm (Authenticated Encryption)

• None
• HmacSHA{1, 256, 384, 512}

IV Length

• 8 (DES & DESede)
• 16 (AES-CBC/CTR mode)
• Varies (GCM)

GCM Tag Length (in bits)

• 96
• 104
• 112
• 120
• 128

Iterations (used when the PBKDF = PBKDF2WithHmacSHA{Length})

• Varies

Download

The easist way is to use jitpack

Usage

Initialization

// Initialize an Alice instance with defaults:
// Cipher = AES/256/CTR/NoPadding
// Key Derivation = PBKDF2WithHmacSHA512/Iterations(10000)
// MAC = HmacSHA512
Alice alice = new Alice(new AliceContextBuilder().build());

AES-CBC or CTR context initialization

AliceContext aliceContext = new AliceContextBuilder()
        .setAlgorithm(AliceContext.Algorithm.AES)
        .setMode(AliceContext.Mode.CBC) // or AliceContext.Mode.CTR
        .setIvLength(16)
        .build()

AES-GCM Context Initialization

AliceContext aliceContext = new AliceContextBuilder()
        .setAlgorithm(AliceContext.Algorithm.AES)
        .setMode(AliceContext.Mode.GCM)
        .setIvLength(ivLength) // e.g. 12
        .setGcmTagLength(AliceContext.GcmTagLength.BITS_128)
        .build()

DES-CBC or CTR Context Initialization

AliceContext aliceContext = new AliceContextBuilder()
        .setAlgorithm(AliceContext.Algorithm.DES)
        .setMode(AliceContext.Mode.CBC) // or AliceContext.Mode.CTR
        .setIvLength(8)
        .build()

3DES-CBC or CTR Context Initialization

AliceContext aliceContext = new AliceContextBuilder()
        .setAlgorithm(AliceContext.Algorithm.DESede)
        .setMode(AliceContext.Mode.CBC) // or AliceContext.Mode.CTR
        .setIvLength(8)
        .build()

Encryption

After you've created an Alice instance with the desired context you can encrypt/decrypt byte arrays and files as shown. See the unit tests for more detailed usage and options.

Working with byte arrays

byte[] encryptedBytes = alice.encrypt(input, password);

byte[] decryptedBytes = alice.decrypt(encryptedBytes, password);

Working with files

alice.encrypt(inputFile, encryptedFile, password);

alice.decrypt(encryptedFile, decryptedFile, password);

Working with streams

Note: Streaming encryption does not support authenticated encryption. You must set the mac algorithm to AliceContext.MacAlgorithm.NONE

alice.encrypt(inputStream, encryptedStream, password);

alice.decrypt(encryptedStream, decryptedStream, password);