org.bouncycastle.openpgp.operator.bc.BcPGPContentSignerBuilder.java Source code

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Here is the source code for org.bouncycastle.openpgp.operator.bc.BcPGPContentSignerBuilder.java

Source

package org.bouncycastle.openpgp.operator.bc;

import java.io.OutputStream;
import java.security.SecureRandom;

import org.bouncycastle.crypto.CryptoException;
import org.bouncycastle.crypto.Signer;
import org.bouncycastle.crypto.params.ParametersWithRandom;
import org.bouncycastle.openpgp.PGPException;
import org.bouncycastle.openpgp.PGPPrivateKey;
import org.bouncycastle.openpgp.operator.PGPContentSigner;
import org.bouncycastle.openpgp.operator.PGPContentSignerBuilder;
import org.bouncycastle.openpgp.operator.PGPDigestCalculator;
import org.bouncycastle.util.io.TeeOutputStream;

public class BcPGPContentSignerBuilder implements PGPContentSignerBuilder {
    private BcPGPDigestCalculatorProvider digestCalculatorProvider = new BcPGPDigestCalculatorProvider();
    private BcPGPKeyConverter keyConverter = new BcPGPKeyConverter();
    private int hashAlgorithm;
    private SecureRandom random;
    private int keyAlgorithm;

    public BcPGPContentSignerBuilder(int keyAlgorithm, int hashAlgorithm) {
        this.keyAlgorithm = keyAlgorithm;
        this.hashAlgorithm = hashAlgorithm;
    }

    public BcPGPContentSignerBuilder setSecureRandom(SecureRandom random) {
        this.random = random;

        return this;
    }

    public PGPContentSigner build(final int signatureType, final PGPPrivateKey privateKey) throws PGPException {
        final PGPDigestCalculator digestCalculator = digestCalculatorProvider.get(hashAlgorithm);
        final Signer signer = BcImplProvider.createSigner(keyAlgorithm, hashAlgorithm);

        if (random != null) {
            signer.init(true, new ParametersWithRandom(keyConverter.getPrivateKey(privateKey), random));
        } else {
            signer.init(true, keyConverter.getPrivateKey(privateKey));
        }

        return new PGPContentSigner() {
            public int getType() {
                return signatureType;
            }

            public int getHashAlgorithm() {
                return hashAlgorithm;
            }

            public int getKeyAlgorithm() {
                return keyAlgorithm;
            }

            public long getKeyID() {
                return privateKey.getKeyID();
            }

            public OutputStream getOutputStream() {
                return new TeeOutputStream(new SignerOutputStream(signer), digestCalculator.getOutputStream());
            }

            public byte[] getSignature() {
                try {
                    return signer.generateSignature();
                } catch (CryptoException e) { // TODO: need a specific runtime exception for PGP operators.
                    throw new IllegalStateException("unable to create signature");
                }
            }

            public byte[] getDigest() {
                return digestCalculator.getDigest();
            }
        };
    }
}