org.jasypt.encryption.pbe.PooledPBEStringEncryptor Maven / Gradle / Ivy
/*
* =============================================================================
*
* Copyright (c) 2007-2010, The JASYPT team (http://www.jasypt.org)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* =============================================================================
*/
package org.jasypt.encryption.pbe;
import java.security.Provider;
import org.jasypt.commons.CommonUtils;
import org.jasypt.encryption.pbe.config.PBEConfig;
import org.jasypt.exceptions.AlreadyInitializedException;
import org.jasypt.iv.IvGenerator;
import org.jasypt.salt.SaltGenerator;
/**
*
* Pooled implementation of {@link PBEStringEncryptor} that in fact contains
* an array of {@link StandardPBEStringEncryptor} objects which are used
* to attend encrypt and decrypt requests in round-robin. This should
* result in higher performance in multiprocessor systems.
*
*
* Configuration of this class is equivalent to that of
* {@link StandardPBEStringEncryptor}.
*
*
* This class is thread-safe.
*
*
*
* @since 1.7
*
* @author Daniel Fernández
*
*/
public final class PooledPBEStringEncryptor implements PBEStringCleanablePasswordEncryptor {
private final StandardPBEStringEncryptor firstEncryptor;
private PBEConfig config = null;
private int poolSize = 0;
private boolean poolSizeSet = false;
private StandardPBEStringEncryptor[] pool;
private int roundRobin = 0;
/*
* Flag which indicates whether the digester has been initialized or not.
*
* Once initialized, no further modifications to its configuration will
* be allowed.
*/
private boolean initialized = false;
/**
* Creates a new instance of PooledStandardPBEStringEncryptor.
*/
public PooledPBEStringEncryptor() {
super();
this.firstEncryptor = new StandardPBEStringEncryptor();
}
/**
*
* Sets a {@link org.jasypt.encryption.pbe.config.PBEConfig} object
* for the encryptor. If this config
* object is set, it will be asked values for:
*
*
*
* - Algorithm
* - Security Provider (or provider name)
* - Password
* - Hashing iterations for obtaining the encryption key
* - Salt generator
* - Output type (base64, hexadecimal)
* (only StringPBEConfig)
*
*
*
* The non-null values it returns will override the default ones,
* and will be overriden by any values specified with a setX
* method.
*
*
* @param config the PBEConfig object to be used as the
* source for configuration parameters.
*/
public synchronized void setConfig(final PBEConfig config) {
this.firstEncryptor.setConfig(config);
this.config = config;
}
/**
*
* Sets the algorithm to be used for encryption, like
* PBEWithMD5AndDES.
*
*
* This algorithm has to be supported by your JCE provider (if you specify
* one, or the default JVM provider if you don't) and, if it is supported,
* you can also specify mode and padding for
* it, like ALGORITHM/MODE/PADDING.
*
*
* @param algorithm the name of the algorithm to be used.
*/
public void setAlgorithm(final String algorithm) {
this.firstEncryptor.setAlgorithm(algorithm);
}
/**
*
* Sets the password to be used.
*
*
* There is no default value for password, so not setting
* this parameter either from a
* {@link org.jasypt.encryption.pbe.config.PBEConfig} object or from
* a call to setPassword will result in an
* EncryptionInitializationException being thrown during initialization.
*
*
* @param password the password to be used.
*/
public void setPassword(final String password) {
this.firstEncryptor.setPassword(password);
}
/**
*
* Sets the password to be used, as a char[].
*
*
* This allows the password to be specified as a cleanable
* char[] instead of a String, in extreme security conscious environments
* in which no copy of the password as an immutable String should
* be kept in memory.
*
*
* Important: the array specified as a parameter WILL BE COPIED
* in order to be stored as encryptor configuration. The caller of
* this method will therefore be responsible for its cleaning (jasypt
* will only clean the internally stored copy).
*
*
* There is no default value for password, so not setting
* this parameter either from a
* {@link org.jasypt.encryption.pbe.config.PBEConfig} object or from
* a call to setPassword will result in an
* EncryptionInitializationException being thrown during initialization.
*
*
* @since 1.8
*
* @param password the password to be used.
*/
public synchronized void setPasswordCharArray(char[] password) {
this.firstEncryptor.setPasswordCharArray(password);
}
/**
*
* Set the number of hashing iterations applied to obtain the
* encryption key.
*
*
* This mechanism is explained in
* PKCS #5: Password-Based Cryptography Standard.
*
*
* @param keyObtentionIterations the number of iterations
*/
public void setKeyObtentionIterations(final int keyObtentionIterations) {
this.firstEncryptor.setKeyObtentionIterations(keyObtentionIterations);
}
/**
*
* Sets the salt generator to be used. If no salt generator is specified,
* an instance of {@link org.jasypt.salt.RandomSaltGenerator} will be used.
*
*
* @param saltGenerator the salt generator to be used.
*/
public void setSaltGenerator(final SaltGenerator saltGenerator) {
this.firstEncryptor.setSaltGenerator(saltGenerator);
}
/**
*
* Sets the IV generator to be used. If no IV generator is specified,
* an instance of {@link org.jasypt.iv.NoIvGenerator} will be used.
*
*
* @param ivGenerator the IV generator to be used.
*/
public void setIvGenerator(final IvGenerator ivGenerator) {
this.firstEncryptor.setIvGenerator(ivGenerator);
}
/**
*
* Sets the name of the security provider to be asked for the
* encryption algorithm. This security provider has to be registered
* beforehand at the JVM security framework.
*
*
* The provider can also be set with the {@link #setProvider(Provider)}
* method, in which case it will not be necessary neither registering
* the provider beforehand,
* nor calling this {@link #setProviderName(String)} method to specify
* a provider name.
*
*
* Note that a call to {@link #setProvider(Provider)} overrides any value
* set by this method.
*
*
* If no provider name / provider is explicitly set, the default JVM
* provider will be used.
*
*
* @param providerName the name of the security provider to be asked
* for the encryption algorithm.
*/
public void setProviderName(final String providerName) {
this.firstEncryptor.setProviderName(providerName);
}
/**
*
* Sets the security provider to be asked for the encryption algorithm.
* The provider does not have to be registered at the security
* infrastructure beforehand, and its being used here will not result in
* its being registered.
*
*
* If this method is called, calling {@link #setProviderName(String)}
* becomes unnecessary.
*
*
* If no provider name / provider is explicitly set, the default JVM
* provider will be used.
*
*
* @param provider the provider to be asked for the chosen algorithm
*/
public void setProvider(final Provider provider) {
this.firstEncryptor.setProvider(provider);
}
/**
*
* Sets the the form in which String output
* will be encoded. Available encoding types are:
*
*
* - base64 (default)
* - hexadecimal
*
*
* If not set, null will be returned.
*
*
* @param stringOutputType the string output type.
*/
public synchronized void setStringOutputType(final String stringOutputType) {
this.firstEncryptor.setStringOutputType(stringOutputType);
}
/**
*
* Sets the size of the pool of digesters to be created.
*
*
* This parameter is required.
*
*
* @param poolSize size of the pool
*/
public synchronized void setPoolSize(final int poolSize) {
CommonUtils.validateIsTrue(poolSize > 0, "Pool size be > 0");
if (isInitialized()) {
throw new AlreadyInitializedException();
}
this.poolSize = poolSize;
this.poolSizeSet = true;
}
/**
*
* Returns true if the encryptor has already been initialized, false if
* not.
* Initialization happens:
*
*
* - When initialize is called.
* - When encrypt or decrypt are called for the
* first time, if initialize has not been called before.
*
*
* Once an encryptor has been initialized, trying to
* change its configuration will
* result in an AlreadyInitializedException being thrown.
*
*
* @return true if the encryptor has already been initialized, false if
* not.
*/
public boolean isInitialized() {
return this.initialized;
}
/**
*
* Initialize the encryptor.
*
*
* This operation will consist in determining the actual configuration
* values to be used, and then initializing the encryptor with them.
*
* These values are decided by applying the following priorities:
*
*
* - First, the default values are considered (except for password).
*
* - Then, if a
* {@link org.jasypt.encryption.pbe.config.PBEConfig}
* object has been set with
* setConfig, the non-null values returned by its
* getX methods override the default values.
* - Finally, if the corresponding setX method has been called
* on the encryptor itself for any of the configuration parameters,
* the values set by these calls override all of the above.
*
*
* Once an encryptor has been initialized, trying to
* change its configuration will
* result in an AlreadyInitializedException being thrown.
*
*
* @throws EncryptionInitializationException if initialization could not
* be correctly done (for example, no password has been set).
*/
public synchronized void initialize() {
// Double-check to avoid synchronization issues
if (!this.initialized) {
if (this.config != null) {
final Integer configPoolSize = this.config.getPoolSize();
this.poolSize =
((this.poolSizeSet) || (configPoolSize == null))?
this.poolSize : configPoolSize.intValue();
}
if (this.poolSize <= 0) {
throw new IllegalArgumentException("Pool size must be set and > 0");
}
this.pool = this.firstEncryptor.cloneAndInitializeEncryptor(this.poolSize);
this.initialized = true;
}
}
/**
*
* Encrypts a message using the specified configuration.
*
*
* The Strings returned by this method are BASE64-encoded (default) or
* HEXADECIMAL ASCII Strings.
*
*
* The mechanisms applied to perform the encryption operation are described
* in PKCS #5: Password-Based Cryptography Standard.
*
*
* This encryptor uses a salt for each encryption
* operation. The size of the salt depends on the algorithm
* being used. This salt is used
* for creating the encryption key and, if generated by a random generator,
* it is also appended unencrypted at the beginning
* of the results so that a decryption operation can be performed.
*
*
* If a random salt generator is used, two encryption results for
* the same message will always be different
* (except in the case of random salt coincidence). This may enforce
* security by difficulting brute force attacks on sets of data at a time
* and forcing attackers to perform a brute force attack on each separate
* piece of encrypted data.
*
*
* @param message the String message to be encrypted
* @return the result of encryption
* @throws EncryptionOperationNotPossibleException if the encryption
* operation fails, ommitting any further information about the
* cause for security reasons.
* @throws EncryptionInitializationException if initialization could not
* be correctly done (for example, no password has been set).
*/
public String encrypt(final String message) {
// Check initialization
if (!isInitialized()) {
initialize();
}
int poolPosition;
synchronized(this) {
poolPosition = this.roundRobin;
this.roundRobin = (this.roundRobin + 1) % this.poolSize;
}
return this.pool[poolPosition].encrypt(message);
}
/**
*
* Decrypts a message using the specified configuration.
*
*
* This method expects to receive a BASE64-encoded (default)
* or HEXADECIMAL ASCII String.
*
*
* The mechanisms applied to perform the decryption operation are described
* in PKCS #5: Password-Based Cryptography Standard.
*
*
* If a random salt generator is used, this decryption operation will
* expect to find an unencrypted salt at the
* beginning of the encrypted input, so that the decryption operation can be
* correctly performed (there is no other way of knowing it).
*
*
* @param encryptedMessage the String message to be decrypted
* @return the result of decryption
* @throws EncryptionOperationNotPossibleException if the decryption
* operation fails, ommitting any further information about the
* cause for security reasons.
* @throws EncryptionInitializationException if initialization could not
* be correctly done (for example, no password has been set).
*/
public String decrypt(final String encryptedMessage) {
// Check initialization
if (!isInitialized()) {
initialize();
}
int poolPosition;
synchronized(this) {
poolPosition = this.roundRobin;
this.roundRobin = (this.roundRobin + 1) % this.poolSize;
}
return this.pool[poolPosition].decrypt(encryptedMessage);
}
}