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

Go to download
Show more of this group Show more artifacts with this name
Show all versions of bcpg-jdk15on Show documentation
The Bouncy Castle Java API for handling the OpenPGP protocol. This jar contains the OpenPGP API for JDK 1.5 to JDK 1.7. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.
There is a newer version: 1.70
Show newest version
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;
    }

    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();
    }

    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);
    }
}