package org.bouncycastle.openpgp;
import java.io.EOFException;
import java.io.InputStream;
import java.security.NoSuchProviderException;
import java.security.Provider;
import org.bouncycastle.bcpg.BCPGInputStream;
import org.bouncycastle.bcpg.InputStreamPacket;
import org.bouncycastle.bcpg.SymmetricEncIntegrityPacket;
import org.bouncycastle.bcpg.SymmetricKeyEncSessionPacket;
import org.bouncycastle.openpgp.operator.PBEDataDecryptorFactory;
import org.bouncycastle.openpgp.operator.PGPDataDecryptor;
import org.bouncycastle.openpgp.operator.jcajce.JcaPGPDigestCalculatorProviderBuilder;
import org.bouncycastle.openpgp.operator.jcajce.JcePBEDataDecryptorFactoryBuilder;
import org.bouncycastle.util.io.TeeInputStream;
/**
* A password based encryption object.
*/
public class PGPPBEEncryptedData
extends PGPEncryptedData
{
SymmetricKeyEncSessionPacket keyData;
PGPPBEEncryptedData(
SymmetricKeyEncSessionPacket keyData,
InputStreamPacket encData)
{
super(encData);
this.keyData = keyData;
}
/**
* Return the raw input stream for the data stream.
*
* @return InputStream
*/
public InputStream getInputStream()
{
return encData.getInputStream();
}
/**
* Return the decrypted input stream, using the passed in passPhrase.
*
* @param passPhrase
* @param provider
* @return InputStream
* @throws PGPException
* @throws NoSuchProviderException
* @deprecated use PBEDataDecryptorFactory method
*/
public InputStream getDataStream(
char[] passPhrase,
String provider)
throws PGPException, NoSuchProviderException
{
return getDataStream(passPhrase, PGPUtil.getProvider(provider));
}
/**
* Return the decrypted input stream, using the passed in passPhrase.
*
* @param passPhrase
* @param provider
* @return InputStream
* @throws PGPException
* @deprecated use PBEDataDecryptorFactory method
*/
public InputStream getDataStream(
char[] passPhrase,
Provider provider)
throws PGPException
{
return getDataStream(new JcePBEDataDecryptorFactoryBuilder(new JcaPGPDigestCalculatorProviderBuilder().setProvider(provider).build()).setProvider(provider).build(passPhrase));
}
/**
* Return the symmetric key algorithm required to decrypt the data protected by this object.
*
* @param dataDecryptorFactory decryptor factory to use to recover the session data.
* @return the integer encryption algorithm code.
* @throws PGPException if the session data cannot be recovered.
*/
public int getSymmetricAlgorithm(
PBEDataDecryptorFactory dataDecryptorFactory)
throws PGPException
{
byte[] key = dataDecryptorFactory.makeKeyFromPassPhrase(keyData.getEncAlgorithm(), keyData.getS2K());
byte[] sessionData = dataDecryptorFactory.recoverSessionData(keyData.getEncAlgorithm(), key, keyData.getSecKeyData());
return sessionData[0];
}
/**
* Open an input stream which will provide the decrypted data protected by this object.
*
* @param dataDecryptorFactory decryptor factory to use to recover the session data and provide the stream.
* @return the resulting input stream
* @throws PGPException if the session data cannot be recovered or the stream cannot be created.
*/
public InputStream getDataStream(
PBEDataDecryptorFactory dataDecryptorFactory)
throws PGPException
{
try
{
int keyAlgorithm = keyData.getEncAlgorithm();
byte[] key = dataDecryptorFactory.makeKeyFromPassPhrase(keyAlgorithm, keyData.getS2K());
boolean withIntegrityPacket = encData instanceof SymmetricEncIntegrityPacket;
byte[] sessionData = dataDecryptorFactory.recoverSessionData(keyData.getEncAlgorithm(), key, keyData.getSecKeyData());
byte[] sessionKey = new byte[sessionData.length - 1];
System.arraycopy(sessionData, 1, sessionKey, 0, sessionKey.length);
PGPDataDecryptor dataDecryptor = dataDecryptorFactory.createDataDecryptor(withIntegrityPacket, sessionData[0] & 0xff, sessionKey);
encStream = new BCPGInputStream(dataDecryptor.getInputStream(encData.getInputStream()));
if (withIntegrityPacket)
{
truncStream = new TruncatedStream(encStream);
integrityCalculator = dataDecryptor.getIntegrityCalculator();
encStream = new TeeInputStream(truncStream, integrityCalculator.getOutputStream());
}
byte[] iv = new byte[dataDecryptor.getBlockSize()];
for (int i = 0; i != iv.length; i++)
{
int ch = encStream.read();
if (ch < 0)
{
throw new EOFException("unexpected end of stream.");
}
iv[i] = (byte)ch;
}
int v1 = encStream.read();
int v2 = encStream.read();
if (v1 < 0 || v2 < 0)
{
throw new EOFException("unexpected end of stream.");
}
// Note: the oracle attack on "quick check" bytes is not deemed
// a security risk for PBE (see PGPPublicKeyEncryptedData)
boolean repeatCheckPassed = iv[iv.length - 2] == (byte) v1
&& iv[iv.length - 1] == (byte) v2;
// Note: some versions of PGP appear to produce 0 for the extra
// bytes rather than repeating the two previous bytes
boolean zeroesCheckPassed = v1 == 0 && v2 == 0;
if (!repeatCheckPassed && !zeroesCheckPassed)
{
throw new PGPDataValidationException("data check failed.");
}
return encStream;
}
catch (PGPException e)
{
throw e;
}
catch (Exception e)
{
throw new PGPException("Exception creating cipher", e);
}
}
}