org.bouncycastle.openpgp.PGPOnePassSignature Maven / Gradle / Ivy

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The Bouncy Castle Java APIs for the OpenPGP Protocol. The APIs are designed primarily to be used in conjunction with the BC FIPS provider. The APIs may also be used with other providers although if being used in a FIPS context it is the responsibility of the user to ensure that any other providers used are FIPS certified and used appropriately.
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package org.bouncycastle.openpgp;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import org.bouncycastle.bcpg.BCPGInputStream;
import org.bouncycastle.bcpg.BCPGOutputStream;
import org.bouncycastle.bcpg.OnePassSignaturePacket;
import org.bouncycastle.bcpg.Packet;
import org.bouncycastle.openpgp.operator.PGPContentVerifier;
import org.bouncycastle.openpgp.operator.PGPContentVerifierBuilder;
import org.bouncycastle.openpgp.operator.PGPContentVerifierBuilderProvider;

/**
 * A one pass signature object.
 */
public class PGPOnePassSignature
{
    private OnePassSignaturePacket sigPack;
    private int signatureType;

    private PGPContentVerifier verifier;
    private byte lastb;
    private OutputStream sigOut;

    private static OnePassSignaturePacket cast(Packet packet)
        throws IOException
    {
        if (!(packet instanceof OnePassSignaturePacket))
        {
            throw new IOException("unexpected packet in stream: " + packet);
        }
        return (OnePassSignaturePacket)packet;
    }

    public PGPOnePassSignature(
        BCPGInputStream    pIn)
        throws IOException, PGPException
    {
        this(cast(pIn.readPacket()));
    }
    
    PGPOnePassSignature(
        OnePassSignaturePacket sigPack)
        throws PGPException
    {
        this.sigPack = sigPack;
        this.signatureType = sigPack.getSignatureType();
    }

    /**
     * Initialise the signature object for verification.
     *
     * @param verifierBuilderProvider provider for a content verifier builder for the signature type of interest.
     * @param pubKey                  the public key to use for verification
     * @throws PGPException if there's an issue with creating the verifier.
     */
    public void init(PGPContentVerifierBuilderProvider verifierBuilderProvider, PGPPublicKey pubKey)
        throws PGPException
    {
        PGPContentVerifierBuilder verifierBuilder = verifierBuilderProvider.get(sigPack.getKeyAlgorithm(), sigPack.getHashAlgorithm());

        verifier = verifierBuilder.build(pubKey);

        lastb = 0;
        sigOut = verifier.getOutputStream();
    }

    public void update(
        byte b)
    {
        if (signatureType == PGPSignature.CANONICAL_TEXT_DOCUMENT)
        {
            if (b == '\r')
            {
                byteUpdate((byte)'\r');
                byteUpdate((byte)'\n');
            }
            else if (b == '\n')
            {
                if (lastb != '\r')
                {
                    byteUpdate((byte)'\r');
                    byteUpdate((byte)'\n');
                }
            }
            else
            {
                byteUpdate(b);
            }

            lastb = b;
        }
        else
        {
            byteUpdate(b);
        }
    }

    public void update(
        byte[] bytes)
    {
        if (signatureType == PGPSignature.CANONICAL_TEXT_DOCUMENT)
        {
            for (int i = 0; i != bytes.length; i++)
            {
                this.update(bytes[i]);
            }
        }
        else
        {
            blockUpdate(bytes, 0, bytes.length);
        }
    }

    public void update(
        byte[] bytes,
        int off,
        int length)
    {
        if (signatureType == PGPSignature.CANONICAL_TEXT_DOCUMENT)
        {
            int finish = off + length;

            for (int i = off; i != finish; i++)
            {
                this.update(bytes[i]);
            }
        }
        else
        {
            blockUpdate(bytes, off, length);
        }
    }

    private void byteUpdate(byte b)
    {
        try
        {
            sigOut.write(b);
        }
        catch (IOException e)
        {
            throw new PGPRuntimeOperationException(e.getMessage(), e);
        }
    }

    private void blockUpdate(byte[] block, int off, int len)
    {
        try
        {
            sigOut.write(block, off, len);
        }
        catch (IOException e)
        {
            throw new PGPRuntimeOperationException(e.getMessage(), e);
        }
    }

    /**
     * Verify the calculated signature against the passed in PGPSignature.
     *
     * @param pgpSig
     * @return boolean
     * @throws PGPException
     */
    public boolean verify(
        PGPSignature pgpSig)
        throws PGPException
    {
        try
        {
            sigOut.write(pgpSig.getSignatureTrailer());

            sigOut.close();
        }
        catch (IOException e)
        {
            throw new PGPException("unable to add trailer: " + e.getMessage(), e);
        }

        return verifier.verify(pgpSig.getSignature());
    }

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

    public int getSignatureType()
    {
        return sigPack.getSignatureType();
    }

    public int getHashAlgorithm()
    {
        return sigPack.getHashAlgorithm();
    }

    public int getKeyAlgorithm()
    {
        return sigPack.getKeyAlgorithm();
    }

    /**
     * Return true, if the signature is contains any signatures that follow.
     * An bracketing OPS is followed by additional OPS packets and is calculated over all the data between itself
     * and its corresponding signature (it is an attestation for contained signatures).
     *
     * @return true if containing, false otherwise
     */
    public boolean isContaining()
    {
        return sigPack.isContaining();
    }

    public byte[] getEncoded()
        throws IOException
    {
        ByteArrayOutputStream bOut = new ByteArrayOutputStream();

        this.encode(bOut);

        return bOut.toByteArray();
    }

    public void encode(
        OutputStream outStream)
        throws IOException
    {
        BCPGOutputStream out;

        if (outStream instanceof BCPGOutputStream)
        {
            out = (BCPGOutputStream)outStream;
        }
        else
        {
            out = new BCPGOutputStream(outStream);
        }

        out.writePacket(sigPack);
    }
}