/*
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*
* 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
* docs/licenses/cddl.txt
* or http://www.opensource.org/licenses/cddl1.php.
* 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
* docs/licenses/cddl.txt. If applicable,
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* Copyright 2010-2016 UnboundID Corp.
*/
package com.unboundid.directory.sdk.examples;
import java.util.Arrays;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import com.unboundid.asn1.ASN1OctetString;
import com.unboundid.directory.sdk.common.types.Entry;
import com.unboundid.directory.sdk.ds.api.PasswordGenerator;
import com.unboundid.directory.sdk.ds.config.PasswordGeneratorConfig;
import com.unboundid.directory.sdk.ds.types.DirectoryServerContext;
import com.unboundid.ldap.sdk.LDAPException;
import com.unboundid.ldap.sdk.ResultCode;
import com.unboundid.util.ByteString;
import com.unboundid.util.args.ArgumentException;
import com.unboundid.util.args.ArgumentParser;
import com.unboundid.util.args.IntegerArgument;
import com.unboundid.util.args.StringArgument;
/**
* This class provides a simple example of a password generator which may be
* used to generate a password with a specified length using a given character
* set. It has two configuration arguments:
* <UL>
* <LI>charset -- The set of characters that may be included in the generated
* password. If this is not specified, then it will default to the set of
* lowercase and uppercase ASCII letters and ASCII numeric digits.</LI>
* <LI>length -- The number of characters to include in the generated
* password. If this is not specified, then it will default to a value of
* eight.</LI>
* </UL>
*/
public final class ExamplePasswordGenerator
extends PasswordGenerator
{
/**
* The name of the argument that will be used for the argument used to specify
* the character set for the generated passwords.
*/
private static final String ARG_NAME_CHARSET = "charset";
/**
* The name of the argument that will be used for the argument used to specify
* the length for generated passwords.
*/
private static final String ARG_NAME_LENGTH = "length";
/**
* The default character set that will be used for generated passwords.
*/
private static final String DEFAULT_CHARSET =
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
/**
* The default length to use for generated passwords.
*/
private static final int DEFAULT_LENGTH = 8;
// The set of characters to use in generated passwords.
private volatile char[] passwordChars;
// The server context for the server in which this extension is running.
private DirectoryServerContext serverContext;
// The length to use for generated passwords.
private volatile int passwordLength;
/**
* Creates a new instance of this password generator. All password generator
* implementations must include a default constructor, but any initialization
* should generally be done in the {@code initializePasswordGenerator} method.
*/
public ExamplePasswordGenerator()
{
// No implementation required.
}
/**
* Retrieves a human-readable name for this extension.
*
* @return A human-readable name for this extension.
*/
@Override()
public String getExtensionName()
{
return "Example Password Generator";
}
/**
* Retrieves a human-readable description for this extension. Each element
* of the array that is returned will be considered a separate paragraph in
* generated documentation.
*
* @return A human-readable description for this extension, or {@code null}
* or an empty array if no description should be available.
*/
@Override()
public String[] getExtensionDescription()
{
return new String[]
{
"This password generator serves an example that may be used to " +
"demonstrate the process for creating a third-party password " +
"generator. It will generate passwords containing a specified " +
"number of randomly-selected characters from a given character set."
};
}
/**
* Updates the provided argument parser to define any configuration arguments
* which may be used by this password generator. The argument parser may also
* be updated to define relationships between arguments (e.g., to specify
* required, exclusive, or dependent argument sets).
*
* @param parser The argument parser to be updated with the configuration
* arguments which may be used by this password generator.
*
* @throws ArgumentException If a problem is encountered while updating the
* provided argument parser.
*/
@Override()
public void defineConfigArguments(final ArgumentParser parser)
throws ArgumentException
{
// Add an argument that allows you to specify the set of allowed characters.
Character shortIdentifier = null;
String longIdentifier = ARG_NAME_CHARSET;
boolean required = true;
int maxOccurrences = 1;
String placeholder = "{charset}";
String description = "The set of characters that may be included " +
"in generated passwords.";
String defaultValueStr = DEFAULT_CHARSET;
parser.addArgument(new StringArgument(shortIdentifier, longIdentifier,
required, maxOccurrences, placeholder, description, defaultValueStr));
// Add an argument that allows you to specify the length of generated
// passwords.
shortIdentifier = null;
longIdentifier = ARG_NAME_LENGTH;
required = true;
maxOccurrences = 1;
placeholder = "{length}";
description = "The number of characters to include in generated " +
"passwords.";
int lowerBound = 1;
int upperBound = Integer.MAX_VALUE;
int defaultValueInt = DEFAULT_LENGTH;
parser.addArgument(new IntegerArgument(shortIdentifier, longIdentifier,
required, maxOccurrences, placeholder, description, lowerBound,
upperBound, defaultValueInt));
}
/**
* Initializes this password generator.
*
* @param serverContext A handle to the server context for the server in
* which this extension is running.
* @param config The general configuration for this password
* generator.
* @param parser The argument parser which has been initialized from
* the configuration for this password generator.
*
* @throws LDAPException If a problem occurs while initializing this
* password generator.
*/
@Override()
public void initializePasswordGenerator(
final DirectoryServerContext serverContext,
final PasswordGeneratorConfig config,
final ArgumentParser parser)
throws LDAPException
{
serverContext.debugInfo("Beginning password generator initialization");
this.serverContext = serverContext;
// The work we need to do is the same for the initial configuration as for
// a configuration change, so we'll just call the same method in both cases.
applyConfig(parser);
}
/**
* Indicates whether the configuration contained in the provided argument
* parser represents a valid configuration for this extension.
*
* @param config The general configuration for this password
* generator.
* @param parser The argument parser which has been initialized
* with the proposed configuration.
* @param unacceptableReasons A list that can be updated with reasons that
* the proposed configuration is not acceptable.
*
* @return {@code true} if the proposed configuration is acceptable, or
* {@code false} if not.
*/
@Override()
public boolean isConfigurationAcceptable(final PasswordGeneratorConfig config,
final ArgumentParser parser,
final List<String> unacceptableReasons)
{
boolean acceptable = true;
// The argument parser will handle most of the validation. The only
// additional validation to perform is to ensure that the proposed character
// set is not an empty string.
final StringArgument charsetArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_CHARSET);
if ((charsetArg != null) && charsetArg.isPresent())
{
final String valueStr = charsetArg.getValue();
if (valueStr.length() == 0)
{
unacceptableReasons.add(
"The password character set must not be empty.");
acceptable = false;
}
}
return acceptable;
}
/**
* Attempts to apply the configuration contained in the provided argument
* parser.
*
* @param config The general configuration for this password
* generator.
* @param parser The argument parser which has been
* initialized with the new configuration.
* @param adminActionsRequired A list that can be updated with information
* about any administrative actions that may be
* required before one or more of the
* configuration changes will be applied.
* @param messages A list that can be updated with information
* about the result of applying the new
* configuration.
*
* @return A result code that provides information about the result of
* attempting to apply the configuration change.
*/
@Override()
public ResultCode applyConfiguration(final PasswordGeneratorConfig config,
final ArgumentParser parser,
final List<String> adminActionsRequired,
final List<String> messages)
{
// The work we need to do is the same for the initial configuration as for
// a configuration change, so we'll just call the same method in both cases.
applyConfig(parser);
return ResultCode.SUCCESS;
}
/**
* Applies the configuration contained in the provided argument parser.
*
* @param parser The argument parser with the configuration to apply.
*/
private void applyConfig(final ArgumentParser parser)
{
char[] newCharSet = DEFAULT_CHARSET.toCharArray();
int newLength = DEFAULT_LENGTH;
final StringArgument charsetArg =
(StringArgument) parser.getNamedArgument(ARG_NAME_CHARSET);
if ((charsetArg != null) && charsetArg.isPresent())
{
final String valueStr = charsetArg.getValue();
newCharSet = valueStr.toCharArray();
}
final IntegerArgument lengthArg =
(IntegerArgument) parser.getNamedArgument(ARG_NAME_LENGTH);
if ((lengthArg != null) && lengthArg.isPresent())
{
newLength = lengthArg.getValue();
}
passwordChars = newCharSet;
passwordLength = newLength;
serverContext.debugInfo("Set the password character set to " +
new String(passwordChars));
serverContext.debugInfo("Set the password length set to " + passwordLength);
}
/**
* Performs any cleanup which may be necessary when this password generator is
* to be taken out of service.
*/
@Override()
public void finalizePasswordGenerator()
{
// No finalization is required.
}
/**
* Generates a password for the provided user.
*
* @param userEntry The entry of the user for whom to generate the
* password.
*
* @return The generated password.
*
* @throws LDAPException If a problem occurs while attempting to generate a
* password for the user.
*/
@Override()
public ByteString generatePassword(final Entry userEntry)
throws LDAPException
{
// Create local copies for the variables to protect against configuration
// changes while generating a password.
final char[] chars = passwordChars;
final int length = passwordLength;
// Create a new random number generator, since they aren't threadsafe.
// We could use synchronization or thread-locals, but this is good enough.
final Random random = new Random();
final StringBuilder buffer = new StringBuilder(length);
for (int i=0; i < length; i++)
{
buffer.append(chars[random.nextInt(chars.length)]);
}
return new ASN1OctetString(buffer.toString());
}
/**
* Retrieves a map containing examples of configurations that may be used for
* this extension. The map key should be a list of sample arguments, and the
* corresponding value should be a description of the behavior that will be
* exhibited by the extension when used with that configuration.
*
* @return A map containing examples of configurations that may be used for
* this extension. It may be {@code null} or empty if there should
* not be any example argument sets.
*/
@Override()
public Map<List<String>,String> getExamplesArgumentSets()
{
final LinkedHashMap<List<String>,String> exampleMap =
new LinkedHashMap<List<String>,String>(1);
exampleMap.put(
Arrays.asList(ARG_NAME_CHARSET + "=abcdefghijklmnopqrstuvwxyz",
ARG_NAME_LENGTH + "=10"),
"Generate passwords with 10 lowercase ASCII alphabetic letters");
return exampleMap;
}
}
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