package org.spongycastle.openpgp;
import java.io.IOException;
import java.io.OutputStream;
import java.security.NoSuchProviderException;
import java.security.Provider;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.List;
import org.spongycastle.bcpg.BCPGOutputStream;
import org.spongycastle.bcpg.HashAlgorithmTags;
import org.spongycastle.bcpg.PacketTags;
import org.spongycastle.bcpg.SymmetricKeyAlgorithmTags;
import org.spongycastle.jce.provider.BouncyCastleProvider;
import org.spongycastle.openpgp.operator.PBEKeyEncryptionMethodGenerator;
import org.spongycastle.openpgp.operator.PGPDataEncryptor;
import org.spongycastle.openpgp.operator.PGPDataEncryptorBuilder;
import org.spongycastle.openpgp.operator.PGPDigestCalculator;
import org.spongycastle.openpgp.operator.PGPKeyEncryptionMethodGenerator;
import org.spongycastle.openpgp.operator.jcajce.JcaPGPDigestCalculatorProviderBuilder;
import org.spongycastle.openpgp.operator.jcajce.JcePBEKeyEncryptionMethodGenerator;
import org.spongycastle.openpgp.operator.jcajce.JcePGPDataEncryptorBuilder;
import org.spongycastle.openpgp.operator.jcajce.JcePublicKeyKeyEncryptionMethodGenerator;
import org.spongycastle.util.io.TeeOutputStream;
/**
* Generator for encrypted objects.
*/
public class PGPEncryptedDataGenerator
implements SymmetricKeyAlgorithmTags, StreamGenerator
{
/**
* Specifier for SHA-1 S2K PBE generator.
*/
public static final int S2K_SHA1 = HashAlgorithmTags.SHA1;
/**
* Specifier for SHA-224 S2K PBE generator.
*/
public static final int S2K_SHA224 = HashAlgorithmTags.SHA224;
/**
* Specifier for SHA-256 S2K PBE generator.
*/
public static final int S2K_SHA256 = HashAlgorithmTags.SHA256;
/**
* Specifier for SHA-384 S2K PBE generator.
*/
public static final int S2K_SHA384 = HashAlgorithmTags.SHA384;
/**
* Specifier for SHA-512 S2K PBE generator.
*/
public static final int S2K_SHA512 = HashAlgorithmTags.SHA512;
private BCPGOutputStream pOut;
private OutputStream cOut;
private boolean oldFormat = false;
private PGPDigestCalculator digestCalc;
private OutputStream genOut;
private PGPDataEncryptorBuilder dataEncryptorBuilder;
private List methods = new ArrayList();
private int defAlgorithm;
private SecureRandom rand;
private Provider defProvider;
/**
* Base constructor.
*
* @param encAlgorithm the symmetric algorithm to use.
* @param rand source of randomness
* @param provider the provider name to use for encryption algorithms.
* @deprecated use constructor that takes a PGPDataEncryptor
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
SecureRandom rand,
String provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setSecureRandom(rand).setProvider(provider));
}
/**
* Base constructor.
*
* @param encAlgorithm the symmetric algorithm to use.
* @param rand source of randomness
* @param provider the provider to use for encryption algorithms.
* @deprecated use constructor that takes a PGPDataEncryptorBuilder
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
SecureRandom rand,
Provider provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setSecureRandom(rand).setProvider(provider));
}
/**
* Creates a cipher stream which will have an integrity packet
* associated with it.
*
* @param encAlgorithm
* @param withIntegrityPacket
* @param rand
* @param provider
* @deprecated use constructor that takes a PGPDataEncryptorBuilder
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
boolean withIntegrityPacket,
SecureRandom rand,
String provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setWithIntegrityPacket(withIntegrityPacket).setSecureRandom(rand).setProvider(provider));
}
/**
* Creates a cipher stream which will have an integrity packet
* associated with it.
*
* @param encAlgorithm
* @param withIntegrityPacket
* @param rand
* @param provider
* @deprecated use constructor that takes a PGPDataEncryptorBuilder
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
boolean withIntegrityPacket,
SecureRandom rand,
Provider provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setWithIntegrityPacket(withIntegrityPacket).setSecureRandom(rand).setProvider(provider));
}
/**
* Base constructor.
*
* @param encAlgorithm the symmetric algorithm to use.
* @param rand source of randomness
* @param oldFormat PGP 2.6.x compatibility required.
* @param provider the provider to use for encryption algorithms.
* @deprecated use constructor that takes a PGPDataEncryptorBuilder
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
SecureRandom rand,
boolean oldFormat,
String provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setSecureRandom(rand).setProvider(provider), oldFormat);
}
/**
* Base constructor.
*
* @param encAlgorithm the symmetric algorithm to use.
* @param rand source of randomness
* @param oldFormat PGP 2.6.x compatibility required.
* @param provider the provider to use for encryption algorithms.
* @deprecated use constructor that takes a PGPDataEncryptorBuilder
*/
public PGPEncryptedDataGenerator(
int encAlgorithm,
SecureRandom rand,
boolean oldFormat,
Provider provider)
{
this(new JcePGPDataEncryptorBuilder(encAlgorithm).setSecureRandom(rand).setProvider(provider), oldFormat);
}
/**
* Base constructor.
*
* @param encryptorBuilder builder to create actual data encryptor.
*/
public PGPEncryptedDataGenerator(PGPDataEncryptorBuilder encryptorBuilder)
{
this(encryptorBuilder, false);
}
/**
* Base constructor with the option to turn on formatting for PGP 2.6.x compatibility.
*
* @param encryptorBuilder builder to create actual data encryptor.
* @param oldFormat PGP 2.6.x compatibility required.
*/
public PGPEncryptedDataGenerator(PGPDataEncryptorBuilder encryptorBuilder, boolean oldFormat)
{
this.dataEncryptorBuilder = encryptorBuilder;
this.oldFormat = oldFormat;
this.defAlgorithm = dataEncryptorBuilder.getAlgorithm();
this.rand = dataEncryptorBuilder.getSecureRandom();
}
/**
* Add a PBE encryption method to the encrypted object using the default algorithm (S2K_SHA1).
*
* @param passPhrase
* @throws NoSuchProviderException
* @throws PGPException
* @deprecated use addMethod that takes PGPKeyEncryptionMethodGenerator
*/
public void addMethod(
char[] passPhrase)
throws NoSuchProviderException, PGPException
{
addMethod(passPhrase, HashAlgorithmTags.SHA1);
}
/**
* Add a PBE encryption method to the encrypted object.
*
* @param passPhrase passphrase to use to generate key.
* @param s2kDigest digest algorithm to use for S2K calculation
* @throws NoSuchProviderException
* @throws PGPException
* @deprecated use addMethod that takes PGPKeyEncryptionMethodGenerator
*/
public void addMethod(
char[] passPhrase,
int s2kDigest)
throws NoSuchProviderException, PGPException
{
if (defProvider == null)
{
defProvider = new BouncyCastleProvider();
}
addMethod(new JcePBEKeyEncryptionMethodGenerator(passPhrase, new JcaPGPDigestCalculatorProviderBuilder().setProvider(defProvider).build().get(s2kDigest)).setProvider(defProvider).setSecureRandom(rand));
}
/**
* Add a public key encrypted session key to the encrypted object.
*
* @param key
* @throws NoSuchProviderException
* @throws PGPException
* @deprecated use addMethod that takes PGPKeyEncryptionMethodGenerator
*/
public void addMethod(
PGPPublicKey key)
throws NoSuchProviderException, PGPException
{
if (!key.isEncryptionKey())
{
throw new IllegalArgumentException("passed in key not an encryption key!");
}
if (defProvider == null)
{
defProvider = new BouncyCastleProvider();
}
addMethod(new JcePublicKeyKeyEncryptionMethodGenerator(key).setProvider(defProvider).setSecureRandom(rand));
}
/**
* Added a key encryption method to be used to encrypt the session data associated
* with this encrypted data.
*
* @param method key encryption method to use.
*/
public void addMethod(PGPKeyEncryptionMethodGenerator method)
{
methods.add(method);
}
private void addCheckSum(
byte[] sessionInfo)
{
int check = 0;
for (int i = 1; i != sessionInfo.length - 2; i++)
{
check += sessionInfo[i] & 0xff;
}
sessionInfo[sessionInfo.length - 2] = (byte)(check >> 8);
sessionInfo[sessionInfo.length - 1] = (byte)(check);
}
private byte[] createSessionInfo(
int algorithm,
byte[] keyBytes)
{
byte[] sessionInfo = new byte[keyBytes.length + 3];
sessionInfo[0] = (byte) algorithm;
System.arraycopy(keyBytes, 0, sessionInfo, 1, keyBytes.length);
addCheckSum(sessionInfo);
return sessionInfo;
}
/**
* If buffer is non null stream assumed to be partial, otherwise the
* length will be used to output a fixed length packet.
* <p>
* The stream created can be closed off by either calling close()
* on the stream or close() on the generator. Closing the returned
* stream does not close off the OutputStream parameter out.
*
* @param out
* @param length
* @param buffer
* @return
* @throws java.io.IOException
* @throws PGPException
* @throws IllegalStateException
*/
private OutputStream open(
OutputStream out,
long length,
byte[] buffer)
throws IOException, PGPException, IllegalStateException
{
if (cOut != null)
{
throw new IllegalStateException("generator already in open state");
}
if (methods.size() == 0)
{
throw new IllegalStateException("no encryption methods specified");
}
byte[] key = null;
pOut = new BCPGOutputStream(out);
defAlgorithm = dataEncryptorBuilder.getAlgorithm();
rand = dataEncryptorBuilder.getSecureRandom();
if (methods.size() == 1)
{
if (methods.get(0) instanceof PBEKeyEncryptionMethodGenerator)
{
PBEKeyEncryptionMethodGenerator m = (PBEKeyEncryptionMethodGenerator)methods.get(0);
key = m.getKey(dataEncryptorBuilder.getAlgorithm());
pOut.writePacket(((PGPKeyEncryptionMethodGenerator)methods.get(0)).generate(defAlgorithm, null));
}
else
{
key = PGPUtil.makeRandomKey(defAlgorithm, rand);
byte[] sessionInfo = createSessionInfo(defAlgorithm, key);
PGPKeyEncryptionMethodGenerator m = (PGPKeyEncryptionMethodGenerator)methods.get(0);
pOut.writePacket(m.generate(defAlgorithm, sessionInfo));
}
}
else // multiple methods
{
key = PGPUtil.makeRandomKey(defAlgorithm, rand);
byte[] sessionInfo = createSessionInfo(defAlgorithm, key);
for (int i = 0; i != methods.size(); i++)
{
PGPKeyEncryptionMethodGenerator m = (PGPKeyEncryptionMethodGenerator)methods.get(i);
pOut.writePacket(m.generate(defAlgorithm, sessionInfo));
}
}
try
{
PGPDataEncryptor dataEncryptor = dataEncryptorBuilder.build(key);
digestCalc = dataEncryptor.getIntegrityCalculator();
if (buffer == null)
{
//
// we have to add block size + 2 for the generated IV and + 1 + 22 if integrity protected
//
if (digestCalc != null)
{
pOut = new ClosableBCPGOutputStream(out, PacketTags.SYM_ENC_INTEGRITY_PRO, length + dataEncryptor.getBlockSize() + 2 + 1 + 22);
pOut.write(1); // version number
}
else
{
pOut = new ClosableBCPGOutputStream(out, PacketTags.SYMMETRIC_KEY_ENC, length + dataEncryptor.getBlockSize() + 2, oldFormat);
}
}
else
{
if (digestCalc != null)
{
pOut = new ClosableBCPGOutputStream(out, PacketTags.SYM_ENC_INTEGRITY_PRO, buffer);
pOut.write(1); // version number
}
else
{
pOut = new ClosableBCPGOutputStream(out, PacketTags.SYMMETRIC_KEY_ENC, buffer);
}
}
genOut = cOut = dataEncryptor.getOutputStream(pOut);
if (digestCalc != null)
{
genOut = new TeeOutputStream(digestCalc.getOutputStream(), cOut);
}
byte[] inLineIv = new byte[dataEncryptor.getBlockSize() + 2];
rand.nextBytes(inLineIv);
inLineIv[inLineIv.length - 1] = inLineIv[inLineIv.length - 3];
inLineIv[inLineIv.length - 2] = inLineIv[inLineIv.length - 4];
genOut.write(inLineIv);
return new WrappedGeneratorStream(genOut, this);
}
catch (Exception e)
{
throw new PGPException("Exception creating cipher", e);
}
}
/**
* Return an outputstream which will encrypt the data as it is written
* to it.
* <p>
* The stream created can be closed off by either calling close()
* on the stream or close() on the generator. Closing the returned
* stream does not close off the OutputStream parameter out.
*
* @param out
* @param length
* @return OutputStream
* @throws IOException
* @throws PGPException
*/
public OutputStream open(
OutputStream out,
long length)
throws IOException, PGPException
{
return this.open(out, length, null);
}
/**
* Return an outputstream which will encrypt the data as it is written
* to it. The stream will be written out in chunks according to the size of the
* passed in buffer.
* <p>
* The stream created can be closed off by either calling close()
* on the stream or close() on the generator. Closing the returned
* stream does not close off the OutputStream parameter out.
* <p>
* <b>Note</b>: if the buffer is not a power of 2 in length only the largest power of 2
* bytes worth of the buffer will be used.
*
* @param out
* @param buffer the buffer to use.
* @return OutputStream
* @throws IOException
* @throws PGPException
*/
public OutputStream open(
OutputStream out,
byte[] buffer)
throws IOException, PGPException
{
return this.open(out, 0, buffer);
}
/**
* Close off the encrypted object - this is equivalent to calling close on the stream
* returned by the open() method.
* <p>
* <b>Note</b>: This does not close the underlying output stream, only the stream on top of it created by the open() method.
* @throws java.io.IOException
*/
public void close()
throws IOException
{
if (cOut != null)
{
if (digestCalc != null)
{
//
// hand code a mod detection packet
//
BCPGOutputStream bOut = new BCPGOutputStream(genOut, PacketTags.MOD_DETECTION_CODE, 20);
bOut.flush();
byte[] dig = digestCalc.getDigest();
cOut.write(dig);
}
cOut.close();
cOut = null;
pOut = null;
}
}
private class ClosableBCPGOutputStream
extends BCPGOutputStream
{
public ClosableBCPGOutputStream(OutputStream out, int symmetricKeyEnc, byte[] buffer)
throws IOException
{
super(out, symmetricKeyEnc, buffer);
}
public ClosableBCPGOutputStream(OutputStream out, int symmetricKeyEnc, long length, boolean oldFormat)
throws IOException
{
super(out, symmetricKeyEnc, length, oldFormat);
}
public ClosableBCPGOutputStream(OutputStream out, int symEncIntegrityPro, long length)
throws IOException
{
super(out, symEncIntegrityPro, length);
}
public void close()
throws IOException
{
this.finish();
}
}
}