org.bouncycastle.jcajce.provider.asymmetric.rsa.RSAUtil.java Source code

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Here is the source code for org.bouncycastle.jcajce.provider.asymmetric.rsa.RSAUtil.java

Source

package org.bouncycastle.jcajce.provider.asymmetric.rsa;

import java.math.BigInteger;
import java.security.interfaces.RSAPrivateCrtKey;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;

import org.bouncycastle.asn1.ASN1ObjectIdentifier;
import org.bouncycastle.asn1.pkcs.PKCSObjectIdentifiers;
import org.bouncycastle.asn1.x509.X509ObjectIdentifiers;
import org.bouncycastle.crypto.params.RSAKeyParameters;
import org.bouncycastle.crypto.params.RSAPrivateCrtKeyParameters;
import org.bouncycastle.util.Fingerprint;

/**
 * utility class for converting java.security RSA objects into their
 * org.bouncycastle.crypto counterparts.
 */
public class RSAUtil {
    public static final ASN1ObjectIdentifier[] rsaOids = { PKCSObjectIdentifiers.rsaEncryption,
            X509ObjectIdentifiers.id_ea_rsa, PKCSObjectIdentifiers.id_RSAES_OAEP,
            PKCSObjectIdentifiers.id_RSASSA_PSS };

    public static boolean isRsaOid(ASN1ObjectIdentifier algOid) {
        for (int i = 0; i != rsaOids.length; i++) {
            if (algOid.equals(rsaOids[i])) {
                return true;
            }
        }

        return false;
    }

    static RSAKeyParameters generatePublicKeyParameter(RSAPublicKey key) {
        if (key instanceof BCRSAPublicKey) {
            return ((BCRSAPublicKey) key).engineGetKeyParameters();
        }

        return new RSAKeyParameters(false, key.getModulus(), key.getPublicExponent());
    }

    static RSAKeyParameters generatePrivateKeyParameter(RSAPrivateKey key) {
        if (key instanceof BCRSAPrivateKey) {
            return ((BCRSAPrivateKey) key).engineGetKeyParameters();
        }

        if (key instanceof RSAPrivateCrtKey) {
            RSAPrivateCrtKey k = (RSAPrivateCrtKey) key;

            return new RSAPrivateCrtKeyParameters(k.getModulus(), k.getPublicExponent(), k.getPrivateExponent(),
                    k.getPrimeP(), k.getPrimeQ(), k.getPrimeExponentP(), k.getPrimeExponentQ(),
                    k.getCrtCoefficient());
        } else {
            RSAPrivateKey k = key;

            return new RSAKeyParameters(true, k.getModulus(), k.getPrivateExponent());
        }
    }

    static String generateKeyFingerprint(BigInteger modulus) {
        return new Fingerprint(modulus.toByteArray()).toString();
    }

    static String generateExponentFingerprint(BigInteger exponent) {
        return new Fingerprint(exponent.toByteArray(), 32).toString();
    }
}