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package org.bouncycastle.cms.jcajce;
import java.security.GeneralSecurityException;
import java.security.Key;
import java.security.Provider;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.bouncycastle.asn1.ASN1OctetString;
import org.bouncycastle.asn1.pkcs.PBKDF2Params;
import org.bouncycastle.asn1.x509.AlgorithmIdentifier;
import org.bouncycastle.cms.CMSException;
import org.bouncycastle.cms.PasswordRecipient;
import org.bouncycastle.crypto.generators.PKCS5S2ParametersGenerator;
import org.bouncycastle.crypto.params.KeyParameter;
/**
* the RecipientInfo class for a recipient who has been sent a message
* encrypted using a password.
*/
public abstract class JcePasswordRecipient
implements PasswordRecipient
{
private int schemeID = PasswordRecipient.PKCS5_SCHEME2_UTF8;
protected EnvelopedDataHelper helper = new EnvelopedDataHelper(new DefaultJcaJceExtHelper());
private char[] password;
JcePasswordRecipient(
char[] password)
{
this.password = password;
}
public JcePasswordRecipient setPasswordConversionScheme(int schemeID)
{
this.schemeID = schemeID;
return this;
}
public JcePasswordRecipient setProvider(Provider provider)
{
this.helper = new EnvelopedDataHelper(new ProviderJcaJceExtHelper(provider));
return this;
}
public JcePasswordRecipient setProvider(String providerName)
{
this.helper = new EnvelopedDataHelper(new NamedJcaJceExtHelper(providerName));
return this;
}
protected Key extractSecretKey(AlgorithmIdentifier keyEncryptionAlgorithm, AlgorithmIdentifier contentEncryptionAlgorithm, byte[] derivedKey, byte[] encryptedContentEncryptionKey)
throws CMSException
{
Cipher keyEncryptionCipher = helper.createRFC3211Wrapper(keyEncryptionAlgorithm.getAlgorithm());
try
{
IvParameterSpec ivSpec = new IvParameterSpec(ASN1OctetString.getInstance(keyEncryptionAlgorithm.getParameters()).getOctets());
keyEncryptionCipher.init(Cipher.UNWRAP_MODE, new SecretKeySpec(derivedKey, keyEncryptionCipher.getAlgorithm()), ivSpec);
return keyEncryptionCipher.unwrap(encryptedContentEncryptionKey, contentEncryptionAlgorithm.getAlgorithm().getId(), Cipher.SECRET_KEY);
}
catch (GeneralSecurityException e)
{
throw new CMSException("cannot process content encryption key: " + e.getMessage(), e);
}
}
public byte[] calculateDerivedKey(byte[] encodedPassword, AlgorithmIdentifier derivationAlgorithm, int keySize)
throws CMSException
{
PBKDF2Params params = PBKDF2Params.getInstance(derivationAlgorithm.getParameters());
PKCS5S2ParametersGenerator gen = new PKCS5S2ParametersGenerator();
gen.init(encodedPassword, params.getSalt(), params.getIterationCount().intValue());
return ((KeyParameter)gen.generateDerivedParameters(keySize)).getKey();
}
public int getPasswordConversionScheme()
{
return schemeID;
}
public char[] getPassword()
{
return password;
}
}
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