/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
* or http://forgerock.org/license/CDDLv1.0.html.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at legal-notices/CDDLv1_0.txt.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information:
* Portions Copyright [yyyy] [name of copyright owner]
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* CDDL HEADER END
*
*
* Copyright 2013-2015 ForgeRock AS.
*/
package org.opends.server.extensions;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.spec.KeySpec;
import java.util.Arrays;
import java.util.List;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.PBEKeySpec;
import org.forgerock.i18n.LocalizableMessage;
import org.forgerock.i18n.slf4j.LocalizedLogger;
import org.forgerock.opendj.config.server.ConfigException;
import org.forgerock.opendj.ldap.ByteSequence;
import org.forgerock.opendj.ldap.ByteString;
import org.forgerock.opendj.ldap.ResultCode;
import org.opends.server.admin.server.ConfigurationChangeListener;
import org.opends.server.admin.std.server.PBKDF2PasswordStorageSchemeCfg;
import org.opends.server.api.PasswordStorageScheme;
import org.opends.server.core.DirectoryServer;
import org.forgerock.opendj.config.server.ConfigChangeResult;
import org.opends.server.types.DirectoryException;
import org.opends.server.types.InitializationException;
import org.opends.server.util.Base64;
import static org.opends.messages.ExtensionMessages.*;
import static org.opends.server.extensions.ExtensionsConstants.*;
import static org.opends.server.util.StaticUtils.*;
/**
* This class defines a Directory Server password storage scheme based on the
* PBKDF2 algorithm defined in RFC 2898. This is a one-way digest algorithm
* so there is no way to retrieve the original clear-text version of the
* password from the hashed value (although this means that it is not suitable
* for things that need the clear-text password like DIGEST-MD5). This
* implementation uses a configurable number of iterations.
*/
public class PBKDF2PasswordStorageScheme
extends PasswordStorageScheme<PBKDF2PasswordStorageSchemeCfg>
implements ConfigurationChangeListener<PBKDF2PasswordStorageSchemeCfg>
{
private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass();
/** The fully-qualified name of this class. */
private static final String CLASS_NAME = "org.opends.server.extensions.PBKDF2PasswordStorageScheme";
/** The number of bytes of random data to use as the salt when generating the hashes. */
private static final int NUM_SALT_BYTES = 8;
/** The number of bytes the SHA-1 algorithm produces. */
private static final int SHA1_LENGTH = 20;
/** The secure random number generator to use to generate the salt values. */
private SecureRandom random;
/** The current configuration for this storage scheme. */
private volatile PBKDF2PasswordStorageSchemeCfg config;
/**
* Creates a new instance of this password storage scheme. Note that no
* initialization should be performed here, as all initialization should be
* done in the <CODE>initializePasswordStorageScheme</CODE> method.
*/
public PBKDF2PasswordStorageScheme()
{
super();
}
/** {@inheritDoc} */
@Override
public void initializePasswordStorageScheme(PBKDF2PasswordStorageSchemeCfg configuration)
throws ConfigException, InitializationException
{
try
{
random = SecureRandom.getInstance(SECURE_PRNG_SHA1);
// Just try to verify if the algorithm is supported.
SecretKeyFactory.getInstance(MESSAGE_DIGEST_ALGORITHM_PBKDF2);
}
catch (NoSuchAlgorithmException e)
{
throw new InitializationException(null);
}
this.config = configuration;
config.addPBKDF2ChangeListener(this);
}
/** {@inheritDoc} */
@Override
public boolean isConfigurationChangeAcceptable(PBKDF2PasswordStorageSchemeCfg configuration,
List<LocalizableMessage> unacceptableReasons)
{
return true;
}
/** {@inheritDoc} */
@Override
public ConfigChangeResult applyConfigurationChange(PBKDF2PasswordStorageSchemeCfg configuration)
{
this.config = configuration;
return new ConfigChangeResult();
}
/** {@inheritDoc} */
@Override
public String getStorageSchemeName()
{
return STORAGE_SCHEME_NAME_PBKDF2;
}
/** {@inheritDoc} */
@Override
public ByteString encodePassword(ByteSequence plaintext)
throws DirectoryException
{
byte[] saltBytes = new byte[NUM_SALT_BYTES];
int iterations = config.getPBKDF2Iterations();
byte[] digestBytes = encodeWithRandomSalt(plaintext, saltBytes, iterations,random);
byte[] hashPlusSalt = concatenateHashPlusSalt(saltBytes, digestBytes);
return ByteString.valueOfUtf8(iterations + ":" + Base64.encode(hashPlusSalt));
}
/** {@inheritDoc} */
@Override
public ByteString encodePasswordWithScheme(ByteSequence plaintext)
throws DirectoryException
{
return ByteString.valueOfUtf8('{' + STORAGE_SCHEME_NAME_PBKDF2 + '}' + encodePassword(plaintext));
}
/** {@inheritDoc} */
@Override
public boolean passwordMatches(ByteSequence plaintextPassword, ByteSequence storedPassword) {
// Split the iterations from the stored value (separated by a ':')
// Base64-decode the remaining value and take the last 8 bytes as the salt.
try
{
final String stored = storedPassword.toString();
final int pos = stored.indexOf(':');
if (pos == -1)
{
throw new Exception();
}
final int iterations = Integer.parseInt(stored.substring(0, pos));
byte[] decodedBytes = Base64.decode(stored.substring(pos + 1));
final int saltLength = decodedBytes.length - SHA1_LENGTH;
if (saltLength <= 0)
{
logger.error(ERR_PWSCHEME_INVALID_BASE64_DECODED_STORED_PASSWORD, storedPassword);
return false;
}
final byte[] digestBytes = new byte[SHA1_LENGTH];
final byte[] saltBytes = new byte[saltLength];
System.arraycopy(decodedBytes, 0, digestBytes, 0, SHA1_LENGTH);
System.arraycopy(decodedBytes, SHA1_LENGTH, saltBytes, 0, saltLength);
return encodeAndMatch(plaintextPassword, saltBytes, digestBytes, iterations);
}
catch (Exception e)
{
logger.traceException(e);
logger.error(ERR_PWSCHEME_CANNOT_BASE64_DECODE_STORED_PASSWORD, storedPassword, e);
return false;
}
}
/** {@inheritDoc} */
@Override
public boolean supportsAuthPasswordSyntax()
{
return true;
}
/** {@inheritDoc} */
@Override
public String getAuthPasswordSchemeName()
{
return AUTH_PASSWORD_SCHEME_NAME_PBKDF2;
}
/** {@inheritDoc} */
@Override
public ByteString encodeAuthPassword(ByteSequence plaintext)
throws DirectoryException
{
byte[] saltBytes = new byte[NUM_SALT_BYTES];
int iterations = config.getPBKDF2Iterations();
byte[] digestBytes = encodeWithRandomSalt(plaintext, saltBytes, iterations,random);
// Encode and return the value.
return ByteString.valueOfUtf8(AUTH_PASSWORD_SCHEME_NAME_PBKDF2 + '$'
+ iterations + ':' + Base64.encode(saltBytes) + '$' + Base64.encode(digestBytes));
}
/** {@inheritDoc} */
@Override
public boolean authPasswordMatches(ByteSequence plaintextPassword, String authInfo, String authValue)
{
try
{
int pos = authInfo.indexOf(':');
if (pos == -1)
{
throw new Exception();
}
int iterations = Integer.parseInt(authInfo.substring(0, pos));
byte[] saltBytes = Base64.decode(authInfo.substring(pos + 1));
byte[] digestBytes = Base64.decode(authValue);
return encodeAndMatch(plaintextPassword, saltBytes, digestBytes, iterations);
}
catch (Exception e)
{
logger.traceException(e);
return false;
}
}
/** {@inheritDoc} */
@Override
public boolean isReversible()
{
return false;
}
/** {@inheritDoc} */
@Override
public ByteString getPlaintextValue(ByteSequence storedPassword)
throws DirectoryException
{
LocalizableMessage message = ERR_PWSCHEME_NOT_REVERSIBLE.get(STORAGE_SCHEME_NAME_PBKDF2);
throw new DirectoryException(ResultCode.CONSTRAINT_VIOLATION, message);
}
/** {@inheritDoc} */
@Override
public ByteString getAuthPasswordPlaintextValue(String authInfo, String authValue)
throws DirectoryException
{
LocalizableMessage message = ERR_PWSCHEME_NOT_REVERSIBLE.get(AUTH_PASSWORD_SCHEME_NAME_PBKDF2);
throw new DirectoryException(ResultCode.CONSTRAINT_VIOLATION, message);
}
/** {@inheritDoc} */
@Override
public boolean isStorageSchemeSecure()
{
return true;
}
/**
* Generates an encoded password string from the given clear-text password.
* This method is primarily intended for use when it is necessary to generate a password with the server
* offline (e.g., when setting the initial root user password).
*
* @param passwordBytes The bytes that make up the clear-text password.
* @return The encoded password string, including the scheme name in curly braces.
* @throws DirectoryException If a problem occurs during processing.
*/
public static String encodeOffline(byte[] passwordBytes)
throws DirectoryException
{
byte[] saltBytes = new byte[NUM_SALT_BYTES];
int iterations = 10000;
final ByteString password = ByteString.wrap(passwordBytes);
byte[] digestBytes = encodeWithRandomSalt(password, saltBytes, iterations);
byte[] hashPlusSalt = concatenateHashPlusSalt(saltBytes, digestBytes);
return '{' + STORAGE_SCHEME_NAME_PBKDF2 + '}' + iterations + ':' + Base64.encode(hashPlusSalt);
}
private static byte[] encodeWithRandomSalt(ByteString plaintext, byte[] saltBytes, int iterations)
throws DirectoryException
{
try
{
final SecureRandom random = SecureRandom.getInstance(SECURE_PRNG_SHA1);
return encodeWithRandomSalt(plaintext, saltBytes, iterations, random);
}
catch (DirectoryException e)
{
throw e;
}
catch (Exception e)
{
throw cannotEncodePassword(e);
}
}
private static byte[] encodeWithSalt(ByteSequence plaintext, byte[] saltBytes, int iterations)
throws DirectoryException
{
final char[] plaintextChars = plaintext.toString().toCharArray();
try
{
final SecretKeyFactory factory = SecretKeyFactory.getInstance(MESSAGE_DIGEST_ALGORITHM_PBKDF2);
KeySpec spec = new PBEKeySpec(plaintextChars, saltBytes, iterations, SHA1_LENGTH * 8);
return factory.generateSecret(spec).getEncoded();
}
catch (Exception e)
{
throw cannotEncodePassword(e);
}
finally
{
Arrays.fill(plaintextChars, '0');
}
}
private boolean encodeAndMatch(ByteSequence plaintext, byte[] saltBytes, byte[] digestBytes, int iterations)
{
try
{
final byte[] userDigestBytes = encodeWithSalt(plaintext, saltBytes, iterations);
return Arrays.equals(digestBytes, userDigestBytes);
}
catch (Exception e)
{
return false;
}
}
private static byte[] encodeWithRandomSalt(ByteSequence plaintext, byte[] saltBytes,
int iterations, SecureRandom random)
throws DirectoryException
{
random.nextBytes(saltBytes);
return encodeWithSalt(plaintext, saltBytes, iterations);
}
private static DirectoryException cannotEncodePassword(Exception e)
{
logger.traceException(e);
LocalizableMessage message = ERR_PWSCHEME_CANNOT_ENCODE_PASSWORD.get(CLASS_NAME, getExceptionMessage(e));
return new DirectoryException(DirectoryServer.getServerErrorResultCode(), message, e);
}
private static byte[] concatenateHashPlusSalt(byte[] saltBytes, byte[] digestBytes) {
final byte[] hashPlusSalt = new byte[digestBytes.length + NUM_SALT_BYTES];
System.arraycopy(digestBytes, 0, hashPlusSalt, 0, digestBytes.length);
System.arraycopy(saltBytes, 0, hashPlusSalt, digestBytes.length, NUM_SALT_BYTES);
return hashPlusSalt;
}
}