Examples with DSAPublicKeyParameters org.bouncycastle.crypto.params.DSAPublicKeyParameters used on opensource projects

Example 6 with DSAPublicKeyParameters

use of org.bouncycastle.crypto.params.DSAPublicKeyParameters in project robovm by robovm.

the class DSAKeyPairGenerator method generateKeyPair.

public AsymmetricCipherKeyPair generateKeyPair() {
    DSAParameters dsaParams = param.getParameters();
    BigInteger x = generatePrivateKey(dsaParams.getQ(), param.getRandom());
    BigInteger y = calculatePublicKey(dsaParams.getP(), dsaParams.getG(), x);
    return new AsymmetricCipherKeyPair(new DSAPublicKeyParameters(y, dsaParams), new DSAPrivateKeyParameters(x, dsaParams));
}

Example 7 with DSAPublicKeyParameters

use of org.bouncycastle.crypto.params.DSAPublicKeyParameters in project robovm by robovm.

the class DSASigner method verifySignature.

/**
     * return true if the value r and s represent a DSA signature for
     * the passed in message for standard DSA the message should be a
     * SHA-1 hash of the real message to be verified.
     */
public boolean verifySignature(byte[] message, BigInteger r, BigInteger s) {
    DSAParameters params = key.getParameters();
    BigInteger m = calculateE(params.getQ(), message);
    BigInteger zero = BigInteger.valueOf(0);
    if (zero.compareTo(r) >= 0 || params.getQ().compareTo(r) <= 0) {
        return false;
    }
    if (zero.compareTo(s) >= 0 || params.getQ().compareTo(s) <= 0) {
        return false;
    }
    BigInteger w = s.modInverse(params.getQ());
    BigInteger u1 = m.multiply(w).mod(params.getQ());
    BigInteger u2 = r.multiply(w).mod(params.getQ());
    u1 = params.getG().modPow(u1, params.getP());
    u2 = ((DSAPublicKeyParameters) key).getY().modPow(u2, params.getP());
    BigInteger v = u1.multiply(u2).mod(params.getP()).mod(params.getQ());
    return v.equals(r);
}

Example 8 with DSAPublicKeyParameters

use of org.bouncycastle.crypto.params.DSAPublicKeyParameters in project XobotOS by xamarin.

the class PublicKeyFactory method createKey.

/**
     * Create a public key from the passed in SubjectPublicKeyInfo
     * 
     * @param keyInfo the SubjectPublicKeyInfo containing the key data
     * @return the appropriate key parameter
     * @throws IOException on an error decoding the key
     */
public static AsymmetricKeyParameter createKey(SubjectPublicKeyInfo keyInfo) throws IOException {
    AlgorithmIdentifier algId = keyInfo.getAlgorithmId();
    if (algId.getObjectId().equals(PKCSObjectIdentifiers.rsaEncryption) || algId.getObjectId().equals(X509ObjectIdentifiers.id_ea_rsa)) {
        RSAPublicKeyStructure pubKey = new RSAPublicKeyStructure((ASN1Sequence) keyInfo.getPublicKey());
        return new RSAKeyParameters(false, pubKey.getModulus(), pubKey.getPublicExponent());
    } else if (algId.getObjectId().equals(X9ObjectIdentifiers.dhpublicnumber)) {
        DHPublicKey dhPublicKey = DHPublicKey.getInstance(keyInfo.getPublicKey());
        BigInteger y = dhPublicKey.getY().getValue();
        DHDomainParameters dhParams = DHDomainParameters.getInstance(keyInfo.getAlgorithmId().getParameters());
        BigInteger p = dhParams.getP().getValue();
        BigInteger g = dhParams.getG().getValue();
        BigInteger q = dhParams.getQ().getValue();
        BigInteger j = null;
        if (dhParams.getJ() != null) {
            j = dhParams.getJ().getValue();
        }
        DHValidationParameters validation = null;
        DHValidationParms dhValidationParms = dhParams.getValidationParms();
        if (dhValidationParms != null) {
            byte[] seed = dhValidationParms.getSeed().getBytes();
            BigInteger pgenCounter = dhValidationParms.getPgenCounter().getValue();
            // TODO Check pgenCounter size?
            validation = new DHValidationParameters(seed, pgenCounter.intValue());
        }
        return new DHPublicKeyParameters(y, new DHParameters(p, g, q, j, validation));
    } else if (algId.getObjectId().equals(PKCSObjectIdentifiers.dhKeyAgreement)) {
        DHParameter params = new DHParameter((ASN1Sequence) keyInfo.getAlgorithmId().getParameters());
        DERInteger derY = (DERInteger) keyInfo.getPublicKey();
        BigInteger lVal = params.getL();
        int l = lVal == null ? 0 : lVal.intValue();
        DHParameters dhParams = new DHParameters(params.getP(), params.getG(), null, l);
        return new DHPublicKeyParameters(derY.getValue(), dhParams);
    } else // END android-removed
    if (algId.getObjectId().equals(X9ObjectIdentifiers.id_dsa) || algId.getObjectId().equals(OIWObjectIdentifiers.dsaWithSHA1)) {
        DERInteger derY = (DERInteger) keyInfo.getPublicKey();
        DEREncodable de = keyInfo.getAlgorithmId().getParameters();
        DSAParameters parameters = null;
        if (de != null) {
            DSAParameter params = DSAParameter.getInstance(de.getDERObject());
            parameters = new DSAParameters(params.getP(), params.getQ(), params.getG());
        }
        return new DSAPublicKeyParameters(derY.getValue(), parameters);
    } else if (algId.getObjectId().equals(X9ObjectIdentifiers.id_ecPublicKey)) {
        X962Parameters params = new X962Parameters((DERObject) keyInfo.getAlgorithmId().getParameters());
        ECDomainParameters dParams = null;
        if (params.isNamedCurve()) {
            DERObjectIdentifier oid = (DERObjectIdentifier) params.getParameters();
            X9ECParameters ecP = X962NamedCurves.getByOID(oid);
            if (ecP == null) {
                ecP = SECNamedCurves.getByOID(oid);
                if (ecP == null) {
                    ecP = NISTNamedCurves.getByOID(oid);
                // BEGIN android-removed
                // if (ecP == null)
                // {
                //     ecP = TeleTrusTNamedCurves.getByOID(oid);
                // }
                // END android-removed
                }
            }
            dParams = new ECDomainParameters(ecP.getCurve(), ecP.getG(), ecP.getN(), ecP.getH(), ecP.getSeed());
        } else {
            X9ECParameters ecP = new X9ECParameters((ASN1Sequence) params.getParameters());
            dParams = new ECDomainParameters(ecP.getCurve(), ecP.getG(), ecP.getN(), ecP.getH(), ecP.getSeed());
        }
        DERBitString bits = keyInfo.getPublicKeyData();
        byte[] data = bits.getBytes();
        ASN1OctetString key = new DEROctetString(data);
        X9ECPoint derQ = new X9ECPoint(dParams.getCurve(), key);
        return new ECPublicKeyParameters(derQ.getPoint(), dParams);
    } else {
        throw new RuntimeException("algorithm identifier in key not recognised");
    }
}