/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.cassandra.auth;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Lists;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.cassandra.config.DatabaseDescriptor;
import org.apache.cassandra.cql3.UntypedResultSet;
import org.apache.cassandra.cql3.QueryProcessor;
import org.apache.cassandra.cql3.QueryOptions;
import org.apache.cassandra.cql3.statements.SelectStatement;
import org.apache.cassandra.db.ConsistencyLevel;
import org.apache.cassandra.exceptions.*;
import org.apache.cassandra.service.QueryState;
import org.apache.cassandra.service.StorageService;
import org.apache.cassandra.transport.messages.ResultMessage;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.FBUtilities;
import org.mindrot.jbcrypt.BCrypt;
/**
* PasswordAuthenticator is an IAuthenticator implementation
* that keeps credentials (usernames and bcrypt-hashed passwords)
* internally in C* - in system_auth.credentials CQL3 table.
*/
public class PasswordAuthenticator implements ISaslAwareAuthenticator
{
private static final Logger logger = LoggerFactory.getLogger(PasswordAuthenticator.class);
// 2 ** GENSALT_LOG2_ROUNS rounds of hashing will be performed.
private static final int GENSALT_LOG2_ROUNDS = 10;
// name of the hash column.
private static final String SALTED_HASH = "salted_hash";
private static final String DEFAULT_USER_NAME = Auth.DEFAULT_SUPERUSER_NAME;
private static final String DEFAULT_USER_PASSWORD = Auth.DEFAULT_SUPERUSER_NAME;
private static final String CREDENTIALS_CF = "credentials";
private static final String CREDENTIALS_CF_SCHEMA = String.format("CREATE TABLE %s.%s ("
+ "username text,"
+ "salted_hash text," // salt + hash + number of rounds
+ "options map<text,text>," // for future extensions
+ "PRIMARY KEY(username)"
+ ") WITH gc_grace_seconds=%d",
Auth.AUTH_KS,
CREDENTIALS_CF,
90 * 24 * 60 * 60); // 3 months.
private SelectStatement authenticateStatement;
// No anonymous access.
public boolean requireAuthentication()
{
return true;
}
public Set<Option> supportedOptions()
{
return ImmutableSet.of(Option.PASSWORD);
}
// Let users alter their own password.
public Set<Option> alterableOptions()
{
return ImmutableSet.of(Option.PASSWORD);
}
public AuthenticatedUser authenticate(Map<String, String> credentials) throws AuthenticationException
{
String username = credentials.get(USERNAME_KEY);
if (username == null)
throw new AuthenticationException(String.format("Required key '%s' is missing", USERNAME_KEY));
String password = credentials.get(PASSWORD_KEY);
if (password == null)
throw new AuthenticationException(String.format("Required key '%s' is missing", PASSWORD_KEY));
UntypedResultSet result;
try
{
ResultMessage.Rows rows = authenticateStatement.execute(QueryState.forInternalCalls(),
new QueryOptions(consistencyForUser(username),
Lists.newArrayList(ByteBufferUtil.bytes(username))));
result = UntypedResultSet.create(rows.result);
}
catch (RequestValidationException e)
{
throw new AssertionError(e); // not supposed to happen
}
catch (RequestExecutionException e)
{
throw new AuthenticationException(e.toString());
}
if (result.isEmpty() || !BCrypt.checkpw(password, result.one().getString(SALTED_HASH)))
throw new AuthenticationException("Username and/or password are incorrect");
return new AuthenticatedUser(username);
}
public void create(String username, Map<Option, Object> options) throws InvalidRequestException, RequestExecutionException
{
String password = (String) options.get(Option.PASSWORD);
if (password == null)
throw new InvalidRequestException("PasswordAuthenticator requires PASSWORD option");
process(String.format("INSERT INTO %s.%s (username, salted_hash) VALUES ('%s', '%s')",
Auth.AUTH_KS,
CREDENTIALS_CF,
escape(username),
escape(hashpw(password))),
consistencyForUser(username));
}
public void alter(String username, Map<Option, Object> options) throws RequestExecutionException
{
process(String.format("UPDATE %s.%s SET salted_hash = '%s' WHERE username = '%s'",
Auth.AUTH_KS,
CREDENTIALS_CF,
escape(hashpw((String) options.get(Option.PASSWORD))),
escape(username)),
consistencyForUser(username));
}
public void drop(String username) throws RequestExecutionException
{
process(String.format("DELETE FROM %s.%s WHERE username = '%s'", Auth.AUTH_KS, CREDENTIALS_CF, escape(username)),
consistencyForUser(username));
}
public Set<DataResource> protectedResources()
{
return ImmutableSet.of(DataResource.columnFamily(Auth.AUTH_KS, CREDENTIALS_CF));
}
public void validateConfiguration() throws ConfigurationException
{
}
public void setup()
{
Auth.setupTable(CREDENTIALS_CF, CREDENTIALS_CF_SCHEMA);
// the delay is here to give the node some time to see its peers - to reduce
// "skipped default user setup: some nodes are were not ready" log spam.
// It's the only reason for the delay.
if (DatabaseDescriptor.getSeeds().contains(FBUtilities.getBroadcastAddress()) || !DatabaseDescriptor.isAutoBootstrap())
{
StorageService.tasks.schedule(new Runnable()
{
public void run()
{
setupDefaultUser();
}
},
Auth.SUPERUSER_SETUP_DELAY,
TimeUnit.MILLISECONDS);
}
try
{
String query = String.format("SELECT %s FROM %s.%s WHERE username = ?",
SALTED_HASH,
Auth.AUTH_KS,
CREDENTIALS_CF);
authenticateStatement = (SelectStatement) QueryProcessor.parseStatement(query).prepare().statement;
}
catch (RequestValidationException e)
{
throw new AssertionError(e); // not supposed to happen
}
}
public SaslAuthenticator newAuthenticator()
{
return new PlainTextSaslAuthenticator();
}
// if there are no users yet - add default superuser.
private void setupDefaultUser()
{
try
{
// insert the default superuser if AUTH_KS.CREDENTIALS_CF is empty.
if (!hasExistingUsers())
{
process(String.format("INSERT INTO %s.%s (username, salted_hash) VALUES ('%s', '%s') USING TIMESTAMP 0",
Auth.AUTH_KS,
CREDENTIALS_CF,
DEFAULT_USER_NAME,
escape(hashpw(DEFAULT_USER_PASSWORD))),
ConsistencyLevel.QUORUM);
logger.info("PasswordAuthenticator created default user '{}'", DEFAULT_USER_NAME);
}
}
catch (RequestExecutionException e)
{
logger.warn("PasswordAuthenticator skipped default user setup: some nodes were not ready");
}
}
private static boolean hasExistingUsers() throws RequestExecutionException
{
// Try looking up the 'cassandra' default user first, to avoid the range query if possible.
String defaultSUQuery = String.format("SELECT * FROM %s.%s WHERE username = '%s'", Auth.AUTH_KS, CREDENTIALS_CF, DEFAULT_USER_NAME);
String allUsersQuery = String.format("SELECT * FROM %s.%s LIMIT 1", Auth.AUTH_KS, CREDENTIALS_CF);
return !process(defaultSUQuery, ConsistencyLevel.QUORUM).isEmpty() || !process(allUsersQuery, ConsistencyLevel.QUORUM).isEmpty();
}
private static String hashpw(String password)
{
return BCrypt.hashpw(password, BCrypt.gensalt(GENSALT_LOG2_ROUNDS));
}
private static String escape(String name)
{
return StringUtils.replace(name, "'", "''");
}
private static UntypedResultSet process(String query, ConsistencyLevel cl) throws RequestExecutionException
{
return QueryProcessor.process(query, cl);
}
private static ConsistencyLevel consistencyForUser(String username)
{
if (username.equals(DEFAULT_USER_NAME))
return ConsistencyLevel.QUORUM;
else
return ConsistencyLevel.ONE;
}
private class PlainTextSaslAuthenticator implements ISaslAwareAuthenticator.SaslAuthenticator
{
private static final byte NUL = 0;
private boolean complete = false;
private Map<String, String> credentials;
@Override
public byte[] evaluateResponse(byte[] clientResponse) throws AuthenticationException
{
credentials = decodeCredentials(clientResponse);
complete = true;
return null;
}
@Override
public boolean isComplete()
{
return complete;
}
@Override
public AuthenticatedUser getAuthenticatedUser() throws AuthenticationException
{
return authenticate(credentials);
}
/**
* SASL PLAIN mechanism specifies that credentials are encoded in a
* sequence of UTF-8 bytes, delimited by 0 (US-ASCII NUL).
* The form is : {code}authzId<NUL>authnId<NUL>password<NUL>{code}
* authzId is optional, and in fact we don't care about it here as we'll
* set the authzId to match the authnId (that is, there is no concept of
* a user being authorized to act on behalf of another).
*
* @param bytes encoded credentials string sent by the client
* @return map containing the username/password pairs in the form an IAuthenticator
* would expect
* @throws javax.security.sasl.SaslException
*/
private Map<String, String> decodeCredentials(byte[] bytes) throws AuthenticationException
{
logger.debug("Decoding credentials from client token");
byte[] user = null;
byte[] pass = null;
int end = bytes.length;
for (int i = bytes.length - 1 ; i >= 0; i--)
{
if (bytes[i] == NUL)
{
if (pass == null)
pass = Arrays.copyOfRange(bytes, i + 1, end);
else if (user == null)
user = Arrays.copyOfRange(bytes, i + 1, end);
end = i;
}
}
if (user == null)
throw new AuthenticationException("Authentication ID must not be null");
if (pass == null)
throw new AuthenticationException("Password must not be null");
Map<String, String> credentials = new HashMap<String, String>();
credentials.put(IAuthenticator.USERNAME_KEY, new String(user, StandardCharsets.UTF_8));
credentials.put(IAuthenticator.PASSWORD_KEY, new String(pass, StandardCharsets.UTF_8));
return credentials;
}
}
}