diff options
Diffstat (limited to 'prov/src/main/java/org/spongycastle/jcajce/provider/symmetric/util/BaseStreamCipher.java')
| -rw-r--r-- | prov/src/main/java/org/spongycastle/jcajce/provider/symmetric/util/BaseStreamCipher.java | 359 |
1 files changed, 359 insertions, 0 deletions
diff --git a/prov/src/main/java/org/spongycastle/jcajce/provider/symmetric/util/BaseStreamCipher.java b/prov/src/main/java/org/spongycastle/jcajce/provider/symmetric/util/BaseStreamCipher.java new file mode 100644 index 00000000..e362f383 --- /dev/null +++ b/prov/src/main/java/org/spongycastle/jcajce/provider/symmetric/util/BaseStreamCipher.java @@ -0,0 +1,359 @@ +package org.spongycastle.jcajce.provider.symmetric.util; + +import java.security.AlgorithmParameters; +import java.security.InvalidAlgorithmParameterException; +import java.security.InvalidKeyException; +import java.security.InvalidParameterException; +import java.security.Key; +import java.security.SecureRandom; +import java.security.spec.AlgorithmParameterSpec; + +import javax.crypto.Cipher; +import javax.crypto.NoSuchPaddingException; +import javax.crypto.SecretKey; +import javax.crypto.ShortBufferException; +import javax.crypto.spec.IvParameterSpec; +import javax.crypto.spec.PBEParameterSpec; +import javax.crypto.spec.RC2ParameterSpec; +import javax.crypto.spec.RC5ParameterSpec; + +import org.spongycastle.crypto.CipherParameters; +import org.spongycastle.crypto.DataLengthException; +import org.spongycastle.crypto.StreamCipher; +import org.spongycastle.crypto.params.KeyParameter; +import org.spongycastle.crypto.params.ParametersWithIV; +import org.spongycastle.jce.provider.BouncyCastleProvider; + +public class BaseStreamCipher + extends BaseWrapCipher + implements PBE +{ + // + // specs we can handle. + // + private Class[] availableSpecs = + { + RC2ParameterSpec.class, + RC5ParameterSpec.class, + IvParameterSpec.class, + PBEParameterSpec.class + }; + + private StreamCipher cipher; + private ParametersWithIV ivParam; + + private int ivLength = 0; + + private PBEParameterSpec pbeSpec = null; + private String pbeAlgorithm = null; + + protected BaseStreamCipher( + StreamCipher engine, + int ivLength) + { + cipher = engine; + this.ivLength = ivLength; + } + + protected int engineGetBlockSize() + { + return 0; + } + + protected byte[] engineGetIV() + { + return (ivParam != null) ? ivParam.getIV() : null; + } + + protected int engineGetKeySize( + Key key) + { + return key.getEncoded().length * 8; + } + + protected int engineGetOutputSize( + int inputLen) + { + return inputLen; + } + + protected AlgorithmParameters engineGetParameters() + { + if (engineParams == null) + { + if (pbeSpec != null) + { + try + { + AlgorithmParameters engineParams = AlgorithmParameters.getInstance(pbeAlgorithm, BouncyCastleProvider.PROVIDER_NAME); + engineParams.init(pbeSpec); + + return engineParams; + } + catch (Exception e) + { + return null; + } + } + } + + return engineParams; + } + + /** + * should never be called. + */ + protected void engineSetMode( + String mode) + { + if (!mode.equalsIgnoreCase("ECB")) + { + throw new IllegalArgumentException("can't support mode " + mode); + } + } + + /** + * should never be called. + */ + protected void engineSetPadding( + String padding) + throws NoSuchPaddingException + { + if (!padding.equalsIgnoreCase("NoPadding")) + { + throw new NoSuchPaddingException("Padding " + padding + " unknown."); + } + } + + protected void engineInit( + int opmode, + Key key, + AlgorithmParameterSpec params, + SecureRandom random) + throws InvalidKeyException, InvalidAlgorithmParameterException + { + 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."); + } + + if (key instanceof BCPBEKey) + { + BCPBEKey k = (BCPBEKey)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) + { + param = PBE.Util.makePBEParameters(k, params, cipher.getAlgorithmName()); + pbeSpec = (PBEParameterSpec)params; + } + else + { + throw new InvalidAlgorithmParameterException("PBE requires PBE parameters to be set."); + } + + if (k.getIvSize() != 0) + { + ivParam = (ParametersWithIV)param; + } + } + else if (params == null) + { + param = new KeyParameter(key.getEncoded()); + } + else if (params instanceof IvParameterSpec) + { + param = new ParametersWithIV(new KeyParameter(key.getEncoded()), ((IvParameterSpec)params).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 + { + throw new InvalidAlgorithmParameterException("no IV set when one expected"); + } + } + + 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 void engineInit( + int opmode, + Key key, + AlgorithmParameters params, + SecureRandom random) + throws InvalidKeyException, InvalidAlgorithmParameterException + { + 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 void engineInit( + int opmode, + Key key, + SecureRandom random) + throws InvalidKeyException + { + try + { + engineInit(opmode, key, (AlgorithmParameterSpec)null, random); + } + catch (InvalidAlgorithmParameterException e) + { + throw new InvalidKeyException(e.getMessage()); + } + } + + protected byte[] engineUpdate( + byte[] input, + int inputOffset, + int inputLen) + { + byte[] out = new byte[inputLen]; + + cipher.processBytes(input, inputOffset, inputLen, out, 0); + + return out; + } + + protected int engineUpdate( + byte[] input, + int inputOffset, + int inputLen, + byte[] output, + int outputOffset) + throws ShortBufferException + { + try + { + cipher.processBytes(input, inputOffset, inputLen, output, outputOffset); + + return inputLen; + } + catch (DataLengthException e) + { + throw new ShortBufferException(e.getMessage()); + } + } + + protected byte[] engineDoFinal( + byte[] input, + int inputOffset, + int inputLen) + { + if (inputLen != 0) + { + byte[] out = engineUpdate(input, inputOffset, inputLen); + + cipher.reset(); + + return out; + } + + cipher.reset(); + + return new byte[0]; + } + + protected int engineDoFinal( + byte[] input, + int inputOffset, + int inputLen, + byte[] output, + int outputOffset) + { + if (inputLen != 0) + { + cipher.processBytes(input, inputOffset, inputLen, output, outputOffset); + } + + cipher.reset(); + + return inputLen; + } +} |