Example usage for org.bouncycastle.crypto.agreement ECDHBasicAgreement calculateAgreement

Introduction

In this page you can find the example usage for org.bouncycastle.crypto.agreement ECDHBasicAgreement calculateAgreement.

Prototype

public BigInteger calculateAgreement(CipherParameters pubKey) 

Source Link

Usage

From source file:card.CardClient.java

License:Open Source License

/**
 * Get an attribute from the card//from w w  w  . j a  v  a  2  s.co m
 * 
 * @param i Index of the attribute.
 * @return Blinded public key, blinded attribute signature and the attribute
 */
public BigInteger[] getAttribute(byte id, ECPoint nonce) {
    BigInteger[] result = new BigInteger[3];

    int i = 0;
    while (i < attribute.length && attribute_id[i] != id)
        i++;

    if (i >= attribute.length || attribute_id[i] != id) {
        return null;
    }
    result[ATTRIBUTE] = attribute[i];

    // generate a blinding factor b
    blinder = (ECPrivateKey) keyGen.generateKeyPair().getPrivate();

    // blind public key, attribute signature and signed nonce
    try {
        ECDHBasicAgreement agreement = new ECDHBasicAgreement();
        agreement.init(new ECPrivateKeyParameters(blinder.getD(), ecDom));

        result[BLINDED_KEY] = agreement
                .calculateAgreement(new ECPublicKeyParameters(((ECPublicKey) keys.getPublic()).getQ(), ecDom));
        result[BLINDED_SIGNATURE] = agreement
                .calculateAgreement(new ECPublicKeyParameters(signature[i], ecDom));
        result[SIGNED_NONCE] = agreement.calculateAgreement(
                new ECPublicKeyParameters(nonce.multiply(((ECPrivateKey) keys.getPrivate()).getD()), ecDom));
    } catch (Exception e) {
        e.printStackTrace();
    }

    // return blinded public key, blinded attribute signature, blinded signed nonce, attribute
    return result;
}

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From source file:org.fdroid.enigtext.crypto.KeyUtil.java

License:Open Source License

public static BigInteger calculateAgreement(ECDHBasicAgreement agreement, ECPublicKeyParameters remoteKey) {
    synchronized (curve) {
        return agreement.calculateAgreement(remoteKey);
    }//w ww  .  j  a v  a  2s . co  m
}

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