Example usage for org.bouncycastle.crypto Wrapper unwrap

Introduction

In this page you can find the example usage for org.bouncycastle.crypto Wrapper unwrap.

Prototype

public byte[] unwrap(byte[] in, int inOff, int inLen) throws InvalidCipherTextException;

Source Link

Usage

From source file:com.github.horrorho.inflatabledonkey.crypto.rfc6637.RFC6637.java

License:Open Source License

public byte[] unwrap(byte[] data, byte[] fingerprint, BigInteger d) {
    try {/*ww w  . j  av a2  s.  com*/
        logger.trace("-- unwrap() - data: 0x{} fingerprint: 0x{} d: 0x{}", Hex.toHexString(data),
                Hex.toHexString(fingerprint), d.toString(16));
        // TODO write verifcation/ exception handling code.
        ByteBuffer buffer = ByteBuffer.wrap(data);

        int wKeySize = (buffer.getShort() + 7) / 8;
        byte[] wKey = new byte[wKeySize];
        buffer.get(wKey);

        int wrappedSize = Byte.toUnsignedInt(buffer.get());
        byte[] wrapped = new byte[wrappedSize];
        buffer.get(wrapped);

        ECPoint Q = decodePoint(wKey);

        // ECDH assuming curve has a cofactor of 1
        ECPoint S = Q.multiply(d).normalize();

        byte[] hash = kdf.apply(S, fingerprint);

        byte[] derivedKey = Arrays.copyOf(hash, symAlgIDKeyLength);

        Wrapper wrapper = wrapperFactory.get();
        wrapper.init(false, new KeyParameter(derivedKey));
        byte[] unwrap = wrapper.unwrap(wrapped, 0, wrapped.length);

        // TODO sym alg
        byte[] finalize = finalize(unwrap);
        logger.trace("-- unwrap() - unwrapped: 0x{}", Hex.toHexString(finalize));
        return finalize;

    } catch (IOException | InvalidCipherTextException ex) {
        throw new IllegalArgumentException(ex);
    }
}

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From source file:org.keycloak.jose.jwe.alg.AesKeyWrapAlgorithmProvider.java

License:Apache License

@Override
public byte[] decodeCek(byte[] encodedCek, Key encryptionKey) throws Exception {
    Wrapper encrypter = new AESWrapEngine();
    encrypter.init(false, new KeyParameter(encryptionKey.getEncoded()));
    return encrypter.unwrap(encodedCek, 0, encodedCek.length);
}

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