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JCEBlockCipher.javaAPI DocAndroid 1.5 API27978Wed May 06 22:41:06 BST 2009org.bouncycastle.jce.provider

JCEBlockCipher

public class JCEBlockCipher extends WrapCipherSpi implements PBE

Fields Summary
private Class[]
availableSpecs
private org.bouncycastle.crypto.BlockCipher
baseEngine
private org.bouncycastle.crypto.BufferedBlockCipher
cipher
private org.bouncycastle.crypto.params.ParametersWithIV
ivParam
private int
ivLength
private boolean
padded
private PBEParameterSpec
pbeSpec
private String
pbeAlgorithm
private String
modeName
Constructors Summary
protected JCEBlockCipher(org.bouncycastle.crypto.BlockCipher engine)


     
         
    
        baseEngine = engine;

        cipher = new PaddedBufferedBlockCipher(engine);
protected JCEBlockCipher(org.bouncycastle.crypto.BlockCipher engine, int ivLength)

        baseEngine = engine;

        this.cipher = new PaddedBufferedBlockCipher(engine);
        this.ivLength = ivLength / 8;
Methods Summary
protected byte[]engineDoFinal(byte[] input, int inputOffset, int inputLen)

        int     len = 0;
        byte[]  tmp = new byte[engineGetOutputSize(inputLen)];

        if (inputLen != 0)
        {
            len = cipher.processBytes(input, inputOffset, inputLen, tmp, 0);
        }

        try
        {
            len += cipher.doFinal(tmp, len);
        }
        catch (DataLengthException e)
        {
            throw new IllegalBlockSizeException(e.getMessage());
        }
        catch (InvalidCipherTextException e)
        {
            throw new BadPaddingException(e.getMessage());
        }

        byte[]  out = new byte[len];

        System.arraycopy(tmp, 0, out, 0, len);

        return out;
protected intengineDoFinal(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)

        // BEGIN android-note
        // added ShortBufferException to the throws statement
        // END android-note
        int     len = 0;

        // BEGIN android-added
        int outputLen = cipher.getOutputSize(inputLen);

        if (outputLen + outputOffset > output.length) {
            throw new ShortBufferException("need at least " + outputLen + " bytes");
        }
        // BEGIN android-added

        if (inputLen != 0)
        {
                len = cipher.processBytes(input, inputOffset, inputLen, output, outputOffset);
        }

        try
        {
            return (len + cipher.doFinal(output, outputOffset + len));
        }
        catch (DataLengthException e)
        {
            throw new IllegalBlockSizeException(e.getMessage());
        }
        catch (InvalidCipherTextException e)
        {
            throw new BadPaddingException(e.getMessage());
        }
protected intengineGetBlockSize()

        return baseEngine.getBlockSize();
protected byte[]engineGetIV()

        return (ivParam != null) ? ivParam.getIV() : null;
protected intengineGetKeySize(java.security.Key key)

        return key.getEncoded().length * 8;
protected intengineGetOutputSize(int inputLen)

        return cipher.getOutputSize(inputLen);
protected java.security.AlgorithmParametersengineGetParameters()

        if (engineParams == null)
        {
            if (pbeSpec != null)
            {
                try
                {
                    engineParams = AlgorithmParameters.getInstance(pbeAlgorithm, "BC");
                    engineParams.init(pbeSpec);
                }
                catch (Exception e)
                {
                    return null;
                }
            }
            else if (ivParam != null)
            {
                String  name = cipher.getUnderlyingCipher().getAlgorithmName();

                if (name.indexOf('/") >= 0)
                {
                    name = name.substring(0, name.indexOf('/"));
                }

                try
                {
                    engineParams = AlgorithmParameters.getInstance(name, "BC");
                    engineParams.init(ivParam.getIV());
                }
                catch (Exception e)
                {
                    throw new RuntimeException(e.toString());
                }
            }
        }

        return engineParams;
protected voidengineInit(int opmode, java.security.Key key, java.security.spec.AlgorithmParameterSpec params, java.security.SecureRandom random)

        CipherParameters        param;
        
        this.pbeSpec = null;
        this.pbeAlgorithm = null;
        this.engineParams = null;
        
        //
        // basic key check
        //
        if (!(key instanceof SecretKey))
        {
            throw new InvalidKeyException("Key for algorithm " + key.getAlgorithm() + " not suitable for symmetric enryption.");
        }
        
        //
        // for RC5-64 we must have some default parameters
        //
        if (params == null && baseEngine.getAlgorithmName().startsWith("RC5-64"))
        {
            throw new InvalidAlgorithmParameterException("RC5 requires an RC5ParametersSpec to be passed in.");
        }

        //
        // a note on iv's - if ivLength is zero the IV gets ignored (we don't use it).
        //
        if (key instanceof JCEPBEKey)
        {
            JCEPBEKey   k = (JCEPBEKey)key;
            
            if (k.getOID() != null)
            {
                pbeAlgorithm = k.getOID().getId();
            }
            else
            {
                pbeAlgorithm = k.getAlgorithm();
            }
            
            if (k.getParam() != null)
            {
                param = k.getParam();
                pbeSpec = new PBEParameterSpec(k.getSalt(), k.getIterationCount());
            }
            else if (params instanceof PBEParameterSpec)
            {
                pbeSpec = (PBEParameterSpec)params;
                param = PBE.Util.makePBEParameters(k, params, cipher.getUnderlyingCipher().getAlgorithmName());
            }
            else
            {
                throw new InvalidAlgorithmParameterException("PBE requires PBE parameters to be set.");
            }

            if (param instanceof ParametersWithIV)
            {
                ivParam = (ParametersWithIV)param;
            }
        }
        else if (params == null)
        {
            param = new KeyParameter(key.getEncoded());
        }
        else if (params instanceof IvParameterSpec)
        {
            if (ivLength != 0)
            {
                IvParameterSpec p = (IvParameterSpec)params;

                if (p.getIV().length != ivLength)
                {
                    throw new InvalidAlgorithmParameterException("IV must be " + ivLength + " bytes long.");
                }

                param = new ParametersWithIV(new KeyParameter(key.getEncoded()), p.getIV());
                ivParam = (ParametersWithIV)param;
            }
            else
            {
                if (modeName != null && modeName.equals("ECB"))
                {
                    throw new InvalidAlgorithmParameterException("ECB mode does not use an IV");
                }
                
                param = new KeyParameter(key.getEncoded());
            }
        }
        // BEGIN android-removed
        // else if (params instanceof GOST28147ParameterSpec)
        // {
        //     GOST28147ParameterSpec    gost28147Param = (GOST28147ParameterSpec)params;
        //
        //     param = new ParametersWithSBox(
        //                new KeyParameter(key.getEncoded()), ((GOST28147ParameterSpec)params).getSbox());
        //
        //     if (gost28147Param.getIV() != null && ivLength != 0)
        //     {
        //         param = new ParametersWithIV(param, gost28147Param.getIV());
        //         ivParam = (ParametersWithIV)param;
        //     }
        // }
        // END android-removed
        else if (params instanceof RC2ParameterSpec)
        {
            RC2ParameterSpec    rc2Param = (RC2ParameterSpec)params;

            param = new RC2Parameters(key.getEncoded(), ((RC2ParameterSpec)params).getEffectiveKeyBits());

            if (rc2Param.getIV() != null && ivLength != 0)
            {
                param = new ParametersWithIV(param, rc2Param.getIV());
                ivParam = (ParametersWithIV)param;
            }
        }
        else if (params instanceof RC5ParameterSpec)
        {
            RC5ParameterSpec    rc5Param = (RC5ParameterSpec)params;

            param = new RC5Parameters(key.getEncoded(), ((RC5ParameterSpec)params).getRounds());
            if (baseEngine.getAlgorithmName().startsWith("RC5"))
            {
                if (baseEngine.getAlgorithmName().equals("RC5-32"))
                {
                    if (rc5Param.getWordSize() != 32)
                    {
                        throw new InvalidAlgorithmParameterException("RC5 already set up for a word size of 32 not " + rc5Param.getWordSize() + ".");
                    }
                }
                else if (baseEngine.getAlgorithmName().equals("RC5-64"))
                {
                    if (rc5Param.getWordSize() != 64)
                    {
                        throw new InvalidAlgorithmParameterException("RC5 already set up for a word size of 64 not " + rc5Param.getWordSize() + ".");
                    }
                }
            }
            else
            {
                throw new InvalidAlgorithmParameterException("RC5 parameters passed to a cipher that is not RC5.");
            }
            if ((rc5Param.getIV() != null) && (ivLength != 0))
            {
                param = new ParametersWithIV(param, rc5Param.getIV());
                ivParam = (ParametersWithIV)param;
            }
        }
        else
        {
            throw new InvalidAlgorithmParameterException("unknown parameter type.");
        }

        if ((ivLength != 0) && !(param instanceof ParametersWithIV))
        {
            SecureRandom    ivRandom = random;

            if (ivRandom == null)
            {
                ivRandom = new SecureRandom();
            }

            if ((opmode == Cipher.ENCRYPT_MODE) || (opmode == Cipher.WRAP_MODE))
            {
                byte[]  iv = new byte[ivLength];

                ivRandom.nextBytes(iv);
                param = new ParametersWithIV(param, iv);
                ivParam = (ParametersWithIV)param;
            }
            else if (cipher.getUnderlyingCipher().getAlgorithmName().indexOf("PGPCFB") < 0)
            {
                throw new InvalidAlgorithmParameterException("no IV set when one expected");
            }
        }

        if (random != null && padded)
        {
            param = new ParametersWithRandom(param, random);
        }

        try
        {
            switch (opmode)
            {
            case Cipher.ENCRYPT_MODE:
            case Cipher.WRAP_MODE:
                cipher.init(true, param);
                break;
            case Cipher.DECRYPT_MODE:
            case Cipher.UNWRAP_MODE:
                cipher.init(false, param);
                break;
            default:
                throw new InvalidParameterException("unknown opmode " + opmode + " passed");
            }
        }
        catch (Exception e)
        {
            throw new InvalidKeyException(e.getMessage());
        }
protected voidengineInit(int opmode, java.security.Key key, java.security.AlgorithmParameters params, java.security.SecureRandom random)

        AlgorithmParameterSpec  paramSpec = null;

        if (params != null)
        {
            for (int i = 0; i != availableSpecs.length; i++)
            {
                try
                {
                    paramSpec = params.getParameterSpec(availableSpecs[i]);
                    break;
                }
                catch (Exception e)
                {
                    continue;
                }
            }

            if (paramSpec == null)
            {
                throw new InvalidAlgorithmParameterException("can't handle parameter " + params.toString());
            }
        }

        engineInit(opmode, key, paramSpec, random);
        
        engineParams = params;
protected voidengineInit(int opmode, java.security.Key key, java.security.SecureRandom random)

        try
        {
            engineInit(opmode, key, (AlgorithmParameterSpec)null, random);
        }
        catch (InvalidAlgorithmParameterException e)
        {
            throw new InvalidKeyException(e.getMessage());
        }
protected voidengineSetMode(java.lang.String mode)

        modeName = Strings.toUpperCase(mode);

        if (modeName.equals("ECB"))
        {
            ivLength = 0;
            cipher = new PaddedBufferedBlockCipher(baseEngine);
        }
        else if (modeName.equals("CBC"))
        {
            ivLength = baseEngine.getBlockSize();
            cipher = new PaddedBufferedBlockCipher(
                            new CBCBlockCipher(baseEngine));
        }
        else if (modeName.startsWith("OFB"))
        {
            ivLength = baseEngine.getBlockSize();
            if (modeName.length() != 3)
            {
                int wordSize = Integer.parseInt(modeName.substring(3));

                cipher = new PaddedBufferedBlockCipher(
                                new OFBBlockCipher(baseEngine, wordSize));
            }
            else
            {
                cipher = new PaddedBufferedBlockCipher(
                        new OFBBlockCipher(baseEngine, 8 * baseEngine.getBlockSize()));
            }
        }
        else if (modeName.startsWith("CFB"))
        {
            ivLength = baseEngine.getBlockSize();
            if (modeName.length() != 3)
            {
                int wordSize = Integer.parseInt(modeName.substring(3));

                cipher = new PaddedBufferedBlockCipher(
                                new CFBBlockCipher(baseEngine, wordSize));
            }
            else
            {
                cipher = new PaddedBufferedBlockCipher(
                        new CFBBlockCipher(baseEngine, 8 * baseEngine.getBlockSize()));
            }
        }
        // BEGIN android-removed
        // else if (modeName.startsWith("PGP"))
        // {
        //     if (modeName.equalsIgnoreCase("PGPCFBwithIV"))
        //     {
        //         ivLength = baseEngine.getBlockSize();
        //         cipher = new PaddedBufferedBlockCipher(
        //             new PGPCFBBlockCipher(baseEngine, true));
        //     }
        //     else
        //     {
        //         ivLength = baseEngine.getBlockSize();
        //         cipher = new PaddedBufferedBlockCipher(
        //             new PGPCFBBlockCipher(baseEngine, false));
        //     }
        // }
        // else if (modeName.equalsIgnoreCase("OpenPGPCFB"))
        // {
        //     ivLength = 0;
        //     cipher = new PaddedBufferedBlockCipher(
        //         new OpenPGPCFBBlockCipher(baseEngine));
        // }
        // END android-removed
        else if (modeName.startsWith("SIC"))
        {
            ivLength = baseEngine.getBlockSize();
            if (ivLength < 16)
            {
                throw new IllegalArgumentException("Warning: SIC-Mode can become a twotime-pad if the blocksize of the cipher is too small. Use a cipher with a block size of at least 128 bits (e.g. AES)");
            }
            cipher = new BufferedBlockCipher(
                        new SICBlockCipher(baseEngine));
        }
        else if (modeName.startsWith("CTR"))
        {
            ivLength = baseEngine.getBlockSize();
            cipher = new BufferedBlockCipher(
                        new SICBlockCipher(baseEngine));
        }
        else if (modeName.startsWith("GOFB"))
        {
            ivLength = baseEngine.getBlockSize();
            cipher = new BufferedBlockCipher(
                        new GOFBBlockCipher(baseEngine));
        }
        else if (modeName.startsWith("CTS"))
        {
            ivLength = baseEngine.getBlockSize();
            cipher = new CTSBlockCipher(new CBCBlockCipher(baseEngine));
        }
        else
        {
            throw new NoSuchAlgorithmException("can't support mode " + mode);
        }
protected voidengineSetPadding(java.lang.String padding)

        String  paddingName = Strings.toUpperCase(padding);

        if (paddingName.equals("NOPADDING"))
        {
            padded = false;
            
            if (!(cipher instanceof CTSBlockCipher))
            {
                cipher = new BufferedBlockCipher(cipher.getUnderlyingCipher());
            }
        }
        else if (paddingName.equals("PKCS5PADDING") || paddingName.equals("PKCS7PADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher());
        }
        else if (paddingName.equals("ZEROBYTEPADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher(), new ZeroBytePadding());
        }
        else if (paddingName.equals("ISO10126PADDING") || paddingName.equals("ISO10126-2PADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher(), new ISO10126d2Padding());
        }
        else if (paddingName.equals("X9.23PADDING") || paddingName.equals("X923PADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher(), new X923Padding());
        }
        else if (paddingName.equals("ISO7816-4PADDING") || paddingName.equals("ISO9797-1PADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher(), new ISO7816d4Padding());
        }
        else if (paddingName.equals("TBCPADDING"))
        {
            cipher = new PaddedBufferedBlockCipher(cipher.getUnderlyingCipher(), new TBCPadding());
        }
        else if (paddingName.equals("WITHCTS"))
        {
            padded = false;
            cipher = new CTSBlockCipher(cipher.getUnderlyingCipher());
        }
        else
        {
            throw new NoSuchPaddingException("Padding " + padding + " unknown.");
        }
protected byte[]engineUpdate(byte[] input, int inputOffset, int inputLen)

        int     length = cipher.getUpdateOutputSize(inputLen);

        if (length > 0)
        {
                byte[]  out = new byte[length];

                int len = cipher.processBytes(input, inputOffset, inputLen, out, 0);

                if (len == 0)
                {
                    return null;
                }
                else if (len != out.length)
                {
                    byte[]  tmp = new byte[len];

                    System.arraycopy(out, 0, tmp, 0, len);

                    return tmp;
                }

                return out;
        }

        cipher.processBytes(input, inputOffset, inputLen, null, 0);

        return null;
protected intengineUpdate(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)

        try
        {
            return cipher.processBytes(input, inputOffset, inputLen, output, outputOffset);
        }
        catch (DataLengthException e)
        {
            throw new ShortBufferException(e.getMessage());
        }