/*
|
* 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]
|
*
|
* CDDL HEADER END
|
*
|
*
|
* Copyright 2006-2009 Sun Microsystems, Inc.
|
* Portions Copyright 2011-2015 ForgeRock AS.
|
*/
|
package org.opends.server.extensions;
|
|
import java.security.MessageDigest;
|
import java.security.SecureRandom;
|
import java.text.ParseException;
|
import java.util.Arrays;
|
import java.util.List;
|
import org.forgerock.i18n.LocalizableMessage;
|
import org.opends.server.admin.server.ConfigurationChangeListener;
|
import org.opends.server.admin.std.server.CramMD5SASLMechanismHandlerCfg;
|
import org.opends.server.admin.std.server.SASLMechanismHandlerCfg;
|
import org.opends.server.api.*;
|
import org.forgerock.opendj.config.server.ConfigChangeResult;
|
import org.forgerock.opendj.config.server.ConfigException;
|
import org.opends.server.core.BindOperation;
|
import org.opends.server.core.DirectoryServer;
|
import org.opends.server.core.PasswordPolicyState;
|
import org.forgerock.i18n.slf4j.LocalizedLogger;
|
import org.opends.server.types.*;
|
import org.forgerock.opendj.ldap.ResultCode;
|
import org.forgerock.opendj.ldap.ByteString;
|
import static org.opends.messages.ExtensionMessages.*;
|
import static org.opends.server.util.ServerConstants.*;
|
import static org.opends.server.util.StaticUtils.*;
|
|
/**
|
* This class provides an implementation of a SASL mechanism that uses digest
|
* authentication via CRAM-MD5. This is a password-based mechanism that does
|
* not expose the password itself over the wire but rather uses an MD5 hash that
|
* proves the client knows the password. This is similar to the DIGEST-MD5
|
* mechanism, and the primary differences are that CRAM-MD5 only obtains random
|
* data from the server (whereas DIGEST-MD5 uses random data from both the
|
* server and the client), CRAM-MD5 does not allow for an authorization ID in
|
* addition to the authentication ID where DIGEST-MD5 does, and CRAM-MD5 does
|
* not define any integrity and confidentiality mechanisms where DIGEST-MD5
|
* does. This implementation is based on the proposal defined in
|
* draft-ietf-sasl-crammd5-05.
|
*/
|
public class CRAMMD5SASLMechanismHandler
|
extends SASLMechanismHandler<CramMD5SASLMechanismHandlerCfg>
|
implements ConfigurationChangeListener<
|
CramMD5SASLMechanismHandlerCfg>
|
{
|
private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass();
|
|
/** An array filled with the inner pad byte. */
|
private byte[] iPad;
|
|
/** An array filled with the outer pad byte. */
|
private byte[] oPad;
|
|
/** The current configuration for this SASL mechanism handler. */
|
private CramMD5SASLMechanismHandlerCfg currentConfig;
|
|
/** The identity mapper that will be used to map ID strings to user entries. */
|
private IdentityMapper<?> identityMapper;
|
|
/** The message digest engine that will be used to create the MD5 digests. */
|
private MessageDigest md5Digest;
|
|
/**
|
* The lock that will be used to provide threadsafe access to the message
|
* digest.
|
*/
|
private Object digestLock;
|
|
/**
|
* The random number generator that we will use to create the server challenge.
|
*/
|
private SecureRandom randomGenerator;
|
|
|
|
/**
|
* Creates a new instance of this SASL mechanism handler. No initialization
|
* should be done in this method, as it should all be performed in the
|
* <CODE>initializeSASLMechanismHandler</CODE> method.
|
*/
|
public CRAMMD5SASLMechanismHandler()
|
{
|
super();
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public void initializeSASLMechanismHandler(
|
CramMD5SASLMechanismHandlerCfg configuration)
|
throws ConfigException, InitializationException
|
{
|
configuration.addCramMD5ChangeListener(this);
|
currentConfig = configuration;
|
|
// Initialize the variables needed for the MD5 digest creation.
|
digestLock = new Object();
|
randomGenerator = new SecureRandom();
|
|
try
|
{
|
md5Digest = MessageDigest.getInstance("MD5");
|
}
|
catch (Exception e)
|
{
|
logger.traceException(e);
|
|
LocalizableMessage message =
|
ERR_SASLCRAMMD5_CANNOT_GET_MESSAGE_DIGEST.get(getExceptionMessage(e));
|
throw new InitializationException(message, e);
|
}
|
|
|
// Create and fill the iPad and oPad arrays.
|
iPad = new byte[HMAC_MD5_BLOCK_LENGTH];
|
oPad = new byte[HMAC_MD5_BLOCK_LENGTH];
|
Arrays.fill(iPad, CRAMMD5_IPAD_BYTE);
|
Arrays.fill(oPad, CRAMMD5_OPAD_BYTE);
|
|
|
// Get the identity mapper that should be used to find users.
|
DN identityMapperDN = configuration.getIdentityMapperDN();
|
identityMapper = DirectoryServer.getIdentityMapper(identityMapperDN);
|
|
DirectoryServer.registerSASLMechanismHandler(SASL_MECHANISM_CRAM_MD5, this);
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public void finalizeSASLMechanismHandler()
|
{
|
currentConfig.removeCramMD5ChangeListener(this);
|
DirectoryServer.deregisterSASLMechanismHandler(SASL_MECHANISM_CRAM_MD5);
|
}
|
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public void processSASLBind(BindOperation bindOperation)
|
{
|
// The CRAM-MD5 bind process uses two stages. See if the client provided
|
// any credentials. If not, then we're in the first stage so we'll send the
|
// challenge to the client.
|
ByteString clientCredentials = bindOperation.getSASLCredentials();
|
ClientConnection clientConnection = bindOperation.getClientConnection();
|
if (clientCredentials == null)
|
{
|
// The client didn't provide any credentials, so this is the initial
|
// request. Generate some random data to send to the client as the
|
// challenge and store it in the client connection so we can verify the
|
// credentials provided by the client later.
|
byte[] challengeBytes = new byte[16];
|
randomGenerator.nextBytes(challengeBytes);
|
StringBuilder challengeString = new StringBuilder(18);
|
challengeString.append('<');
|
for (byte b : challengeBytes)
|
{
|
challengeString.append(byteToLowerHex(b));
|
}
|
challengeString.append('>');
|
|
final ByteString challenge = ByteString.valueOf(challengeString);
|
clientConnection.setSASLAuthStateInfo(challenge);
|
bindOperation.setServerSASLCredentials(challenge);
|
bindOperation.setResultCode(ResultCode.SASL_BIND_IN_PROGRESS);
|
return;
|
}
|
|
|
// If we've gotten here, then the client did provide credentials. First,
|
// make sure that we have a stored version of the credentials associated
|
// with the client connection. If not, then it likely means that the client
|
// is trying to pull a fast one on us.
|
Object saslStateInfo = clientConnection.getSASLAuthStateInfo();
|
if (saslStateInfo == null)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_NO_STORED_CHALLENGE.get();
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
if (! (saslStateInfo instanceof ByteString))
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_INVALID_STORED_CHALLENGE.get();
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
ByteString challenge = (ByteString) saslStateInfo;
|
|
// Wipe out the stored challenge so it can't be used again.
|
clientConnection.setSASLAuthStateInfo(null);
|
|
|
// Now look at the client credentials and make sure that we can decode them.
|
// It should be a username followed by a space and a digest string. Since
|
// the username itself may contain spaces but the digest string may not,
|
// look for the last space and use it as the delimiter.
|
String credString = clientCredentials.toString();
|
int spacePos = credString.lastIndexOf(' ');
|
if (spacePos < 0)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_NO_SPACE_IN_CREDENTIALS.get();
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
String userName = credString.substring(0, spacePos);
|
String digest = credString.substring(spacePos+1);
|
|
|
// Look at the digest portion of the provided credentials. It must have a
|
// length of exactly 32 bytes and be comprised only of hex characters.
|
if (digest.length() != 2*MD5_DIGEST_LENGTH)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_INVALID_DIGEST_LENGTH.get(
|
digest.length(),
|
2*MD5_DIGEST_LENGTH);
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
byte[] digestBytes;
|
try
|
{
|
digestBytes = hexStringToByteArray(digest);
|
}
|
catch (ParseException pe)
|
{
|
logger.traceException(pe);
|
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_INVALID_DIGEST_CONTENT.get(
|
pe.getMessage());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
|
// Get the user entry for the authentication ID. Allow for an
|
// authentication ID that is just a username (as per the CRAM-MD5 spec), but
|
// also allow a value in the authzid form specified in RFC 2829.
|
Entry userEntry = null;
|
String lowerUserName = toLowerCase(userName);
|
if (lowerUserName.startsWith("dn:"))
|
{
|
// Try to decode the user DN and retrieve the corresponding entry.
|
DN userDN;
|
try
|
{
|
userDN = DN.valueOf(userName.substring(3));
|
}
|
catch (DirectoryException de)
|
{
|
logger.traceException(de);
|
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_CANNOT_DECODE_USERNAME_AS_DN.get(
|
userName, de.getMessageObject());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
if (userDN.isRootDN())
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_USERNAME_IS_NULL_DN.get();
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
DN rootDN = DirectoryServer.getActualRootBindDN(userDN);
|
if (rootDN != null)
|
{
|
userDN = rootDN;
|
}
|
|
try
|
{
|
userEntry = DirectoryServer.getEntry(userDN);
|
}
|
catch (DirectoryException de)
|
{
|
logger.traceException(de);
|
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_CANNOT_GET_ENTRY_BY_DN.get(userDN, de.getMessageObject());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
}
|
else
|
{
|
// Use the identity mapper to resolve the username to an entry.
|
if (lowerUserName.startsWith("u:"))
|
{
|
userName = userName.substring(2);
|
}
|
|
try
|
{
|
userEntry = identityMapper.getEntryForID(userName);
|
}
|
catch (DirectoryException de)
|
{
|
logger.traceException(de);
|
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_CANNOT_MAP_USERNAME.get(userName, de.getMessageObject());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
}
|
|
|
// At this point, we should have a user entry. If we don't then fail.
|
if (userEntry == null)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_NO_MATCHING_ENTRIES.get(userName);
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
else
|
{
|
bindOperation.setSASLAuthUserEntry(userEntry);
|
}
|
|
|
// Get the clear-text passwords from the user entry, if there are any.
|
List<ByteString> clearPasswords;
|
try
|
{
|
AuthenticationPolicyState authState = AuthenticationPolicyState.forUser(
|
userEntry, false);
|
|
if (!authState.isPasswordPolicy())
|
{
|
bindOperation.setResultCode(ResultCode.INAPPROPRIATE_AUTHENTICATION);
|
LocalizableMessage message = ERR_SASL_ACCOUNT_NOT_LOCAL
|
.get(SASL_MECHANISM_CRAM_MD5, userEntry.getName());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
PasswordPolicyState pwPolicyState = (PasswordPolicyState) authState;
|
clearPasswords = pwPolicyState.getClearPasswords();
|
if (clearPasswords == null || clearPasswords.isEmpty())
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_NO_REVERSIBLE_PASSWORDS.get(userEntry.getName());
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
}
|
catch (Exception e)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_CANNOT_GET_REVERSIBLE_PASSWORDS.get( userEntry.getName(), e);
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
|
// Iterate through the clear-text values and see if any of them can be used
|
// in conjunction with the challenge to construct the provided digest.
|
boolean matchFound = false;
|
for (ByteString clearPassword : clearPasswords)
|
{
|
byte[] generatedDigest = generateDigest(clearPassword, challenge);
|
if (Arrays.equals(digestBytes, generatedDigest))
|
{
|
matchFound = true;
|
break;
|
}
|
}
|
|
if (! matchFound)
|
{
|
bindOperation.setResultCode(ResultCode.INVALID_CREDENTIALS);
|
|
LocalizableMessage message = ERR_SASLCRAMMD5_INVALID_PASSWORD.get();
|
bindOperation.setAuthFailureReason(message);
|
return;
|
}
|
|
|
// If we've gotten here, then the authentication was successful.
|
bindOperation.setResultCode(ResultCode.SUCCESS);
|
|
AuthenticationInfo authInfo = new AuthenticationInfo(userEntry,
|
SASL_MECHANISM_CRAM_MD5, DirectoryServer.isRootDN(userEntry.getName()));
|
bindOperation.setAuthenticationInfo(authInfo);
|
}
|
|
|
|
/**
|
* Generates the appropriate HMAC-MD5 digest for a CRAM-MD5 authentication
|
* with the given information.
|
*
|
* @param password The clear-text password to use when generating the
|
* digest.
|
* @param challenge The server-supplied challenge to use when generating the
|
* digest.
|
*
|
* @return The generated HMAC-MD5 digest for CRAM-MD5 authentication.
|
*/
|
private byte[] generateDigest(ByteString password, ByteString challenge)
|
{
|
// Get the byte arrays backing the password and challenge.
|
byte[] p = password.toByteArray();
|
byte[] c = challenge.toByteArray();
|
|
|
// Grab a lock to protect the MD5 digest generation.
|
synchronized (digestLock)
|
{
|
// If the password is longer than the HMAC-MD5 block length, then use an
|
// MD5 digest of the password rather than the password itself.
|
if (p.length > HMAC_MD5_BLOCK_LENGTH)
|
{
|
p = md5Digest.digest(p);
|
}
|
|
|
// Create byte arrays with data needed for the hash generation.
|
byte[] iPadAndData = new byte[HMAC_MD5_BLOCK_LENGTH + c.length];
|
System.arraycopy(iPad, 0, iPadAndData, 0, HMAC_MD5_BLOCK_LENGTH);
|
System.arraycopy(c, 0, iPadAndData, HMAC_MD5_BLOCK_LENGTH, c.length);
|
|
byte[] oPadAndHash = new byte[HMAC_MD5_BLOCK_LENGTH + MD5_DIGEST_LENGTH];
|
System.arraycopy(oPad, 0, oPadAndHash, 0, HMAC_MD5_BLOCK_LENGTH);
|
|
|
// Iterate through the bytes in the key and XOR them with the iPad and
|
// oPad as appropriate.
|
for (int i=0; i < p.length; i++)
|
{
|
iPadAndData[i] ^= p[i];
|
oPadAndHash[i] ^= p[i];
|
}
|
|
|
// Copy an MD5 digest of the iPad-XORed key and the data into the array to
|
// be hashed.
|
System.arraycopy(md5Digest.digest(iPadAndData), 0, oPadAndHash,
|
HMAC_MD5_BLOCK_LENGTH, MD5_DIGEST_LENGTH);
|
|
|
// Return an MD5 digest of the resulting array.
|
return md5Digest.digest(oPadAndHash);
|
}
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public boolean isPasswordBased(String mechanism)
|
{
|
// This is a password-based mechanism.
|
return true;
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public boolean isSecure(String mechanism)
|
{
|
// This may be considered a secure mechanism.
|
return true;
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public boolean isConfigurationAcceptable(
|
SASLMechanismHandlerCfg configuration,
|
List<LocalizableMessage> unacceptableReasons)
|
{
|
CramMD5SASLMechanismHandlerCfg config =
|
(CramMD5SASLMechanismHandlerCfg) configuration;
|
return isConfigurationChangeAcceptable(config, unacceptableReasons);
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public boolean isConfigurationChangeAcceptable(
|
CramMD5SASLMechanismHandlerCfg configuration,
|
List<LocalizableMessage> unacceptableReasons)
|
{
|
return true;
|
}
|
|
|
|
/** {@inheritDoc} */
|
@Override
|
public ConfigChangeResult applyConfigurationChange(
|
CramMD5SASLMechanismHandlerCfg configuration)
|
{
|
final ConfigChangeResult ccr = new ConfigChangeResult();
|
|
DN identityMapperDN = configuration.getIdentityMapperDN();
|
identityMapper = DirectoryServer.getIdentityMapper(identityMapperDN);
|
currentConfig = configuration;
|
|
return ccr;
|
}
|
}
|
