Example usage for org.bouncycastle.crypto.engines ChaCha7539Engine ChaCha7539Engine

Introduction

In this page you can find the example usage for org.bouncycastle.crypto.engines ChaCha7539Engine ChaCha7539Engine.

Prototype

public ChaCha7539Engine() 

Source Link

Document

Creates a 20 rounds ChaCha engine.

Usage

From source file:net.java.otr4j.crypto.OtrCryptoEngine4.java

License:LGPL

/**
 * Encrypt a message using ChaCha20 defined by RFC7539, given the specified key. The nonce is fixed to all
 * zero-bytes, as we expect to use a new key for every encryption operation.
 *
 * @param mkEnc   the secret key used for encryption (at least 32 bytes)
 * @param message the plaintext message to be encrypted (non-null)
 * @return Returns the encrypted content.
 *//*from   w  w w.ja  va2 s.  c o  m*/
@Nonnull
public static byte[] encrypt(final byte[] mkEnc, final byte[] message) {
    requireLengthAtLeast(CHACHA20_KEY_LENGTH_BYTES, mkEnc);
    requireNonNull(message);
    final byte[] key = Arrays.copyOf(mkEnc, CHACHA20_KEY_LENGTH_BYTES);
    assert !allZeroBytes(
            key) : "Expected non-zero byte array for a key. Something critical might be going wrong.";
    try {
        final ChaCha7539Engine engine = new ChaCha7539Engine();
        engine.init(true, new ParametersWithIV(new KeyParameter(key, 0, key.length), IV));
        final byte[] out = new byte[message.length];
        if (engine.processBytes(message, 0, message.length, out, 0) != message.length) {
            throw new IllegalStateException("Expected to process exactly full size of the message.");
        }
        return out;
    } finally {
        clear(key);
    }
}

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From source file:net.java.otr4j.crypto.OtrCryptoEngine4.java

License:LGPL

/**
 * Decrypt a ciphertext using ChaCha20 defined by RFC7539, given the specified key.
 *
 * @param mkEnc      the secret key used for decryption (at least 32 bytes)
 * @param ciphertext te ciphertext to be decrypted (non-null)
 * @return Returns the decrypted (plaintext) content.
 *//*from  w w  w.ja v  a2 s .c  o  m*/
@Nonnull
public static byte[] decrypt(final byte[] mkEnc, final byte[] ciphertext) {
    requireLengthAtLeast(CHACHA20_KEY_LENGTH_BYTES, mkEnc);
    requireNonNull(ciphertext);
    final byte[] key = Arrays.copyOf(mkEnc, CHACHA20_KEY_LENGTH_BYTES);
    assert !allZeroBytes(
            key) : "Expected non-zero byte array for a key. Something critical might be going wrong.";
    try {
        final ChaCha7539Engine engine = new ChaCha7539Engine();
        engine.init(false, new ParametersWithIV(new KeyParameter(key, 0, key.length), IV));
        final byte[] out = new byte[ciphertext.length];
        if (engine.processBytes(ciphertext, 0, ciphertext.length, out, 0) != ciphertext.length) {
            throw new IllegalStateException("Expected to process exactly full size of the message.");
        }
        return out;
    } finally {
        clear(key);
    }
}

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From source file:shadowsocks.crypto.Chacha20Crypto.java

License:Apache License

@Override
protected StreamCipher createCipher(byte[] iv, boolean encrypt) throws CryptoException {
    StreamCipher c;//w w  w. ja v  a 2  s.co  m
    if (mName.equals(CIPHER_CHACHA20_IETF)) {
        c = new ChaCha7539Engine();
    } else {
        c = new ChaChaEngine();
    }
    ParametersWithIV parameterIV = new ParametersWithIV(new KeyParameter(mKey), iv, 0, mIVLength);
    c.init(encrypt, parameterIV);
    return c;
}

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