001/*
002 * Copyright 2007-2020 Ping Identity Corporation
003 * All Rights Reserved.
004 */
005/*
006 * Copyright 2007-2020 Ping Identity Corporation
007 *
008 * Licensed under the Apache License, Version 2.0 (the "License");
009 * you may not use this file except in compliance with the License.
010 * You may obtain a copy of the License at
011 *
012 *    http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing, software
015 * distributed under the License is distributed on an "AS IS" BASIS,
016 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
017 * See the License for the specific language governing permissions and
018 * limitations under the License.
019 */
020/*
021 * Copyright (C) 2008-2020 Ping Identity Corporation
022 *
023 * This program is free software; you can redistribute it and/or modify
024 * it under the terms of the GNU General Public License (GPLv2 only)
025 * or the terms of the GNU Lesser General Public License (LGPLv2.1 only)
026 * as published by the Free Software Foundation.
027 *
028 * This program is distributed in the hope that it will be useful,
029 * but WITHOUT ANY WARRANTY; without even the implied warranty of
030 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
031 * GNU General Public License for more details.
032 *
033 * You should have received a copy of the GNU General Public License
034 * along with this program; if not, see <http://www.gnu.org/licenses>.
035 */
036package com.unboundid.ldap.sdk.controls;
037
038
039
040import java.util.ArrayList;
041import java.util.Collection;
042
043import com.unboundid.asn1.ASN1Element;
044import com.unboundid.asn1.ASN1Exception;
045import com.unboundid.asn1.ASN1OctetString;
046import com.unboundid.asn1.ASN1Sequence;
047import com.unboundid.ldap.sdk.Attribute;
048import com.unboundid.ldap.sdk.Control;
049import com.unboundid.ldap.sdk.DecodeableControl;
050import com.unboundid.ldap.sdk.LDAPException;
051import com.unboundid.ldap.sdk.LDAPResult;
052import com.unboundid.ldap.sdk.ReadOnlyEntry;
053import com.unboundid.ldap.sdk.ResultCode;
054import com.unboundid.util.Debug;
055import com.unboundid.util.NotMutable;
056import com.unboundid.util.ThreadSafety;
057import com.unboundid.util.ThreadSafetyLevel;
058import com.unboundid.util.Validator;
059
060import static com.unboundid.ldap.sdk.controls.ControlMessages.*;
061
062
063
064/**
065 * This class provides an implementation of the LDAP pre-read response control
066 * as defined in <A HREF="http://www.ietf.org/rfc/rfc4527.txt">RFC 4527</A>.  It
067 * may be used to return a copy of the target entry immediately before
068 * processing a delete, modify, or modify DN operation.
069 * <BR><BR>
070 * If the corresponding delete, modify, or modify DN request included the
071 * {@link PreReadRequestControl} and the operation was successful, then the
072 * response for that operation should include the pre-read response control with
073 * a read-only copy of the entry as it appeared immediately before processing
074 * the request.  If the operation was not successful, then the pre-read response
075 * control will not be returned.
076 */
077@NotMutable()
078@ThreadSafety(level=ThreadSafetyLevel.COMPLETELY_THREADSAFE)
079public final class PreReadResponseControl
080       extends Control
081       implements DecodeableControl
082{
083  /**
084   * The OID (1.3.6.1.1.13.1) for the pre-read response control.
085   */
086  public static final String PRE_READ_RESPONSE_OID = "1.3.6.1.1.13.1";
087
088
089
090  /**
091   * The serial version UID for this serializable class.
092   */
093  private static final long serialVersionUID = -4719875382095056686L;
094
095
096
097  // The entry returned in the response control.
098  private final ReadOnlyEntry entry;
099
100
101
102  /**
103   * Creates a new empty control instance that is intended to be used only for
104   * decoding controls via the {@code DecodeableControl} interface.
105   */
106  PreReadResponseControl()
107  {
108    entry = null;
109  }
110
111
112
113  /**
114   * Creates a new pre-read response control including the provided entry.
115   *
116   * @param  entry  The entry to include in this pre-read response control.  It
117   *                must not be {@code null}.
118   */
119  public PreReadResponseControl(final ReadOnlyEntry entry)
120  {
121    super(PRE_READ_RESPONSE_OID, false, encodeValue(entry));
122
123    this.entry = entry;
124  }
125
126
127
128  /**
129   * Creates a new pre-read response control with the provided information.
130   *
131   * @param  oid         The OID for the control.
132   * @param  isCritical  Indicates whether the control should be marked
133   *                     critical.
134   * @param  value       The encoded value for the control.  This may be
135   *                     {@code null} if no value was provided.
136   *
137   * @throws  LDAPException  If the provided control cannot be decoded as a
138   *                         pre-read response control.
139   */
140  public PreReadResponseControl(final String oid, final boolean isCritical,
141                                final ASN1OctetString value)
142         throws LDAPException
143  {
144    super(oid, isCritical, value);
145
146    if (value == null)
147    {
148      throw new LDAPException(ResultCode.DECODING_ERROR,
149                              ERR_PRE_READ_RESPONSE_NO_VALUE.get());
150    }
151
152    final ASN1Sequence entrySequence;
153    try
154    {
155      final ASN1Element entryElement = ASN1Element.decode(value.getValue());
156      entrySequence = ASN1Sequence.decodeAsSequence(entryElement);
157    }
158    catch (final ASN1Exception ae)
159    {
160      Debug.debugException(ae);
161      throw new LDAPException(ResultCode.DECODING_ERROR,
162                              ERR_PRE_READ_RESPONSE_VALUE_NOT_SEQUENCE.get(ae),
163                              ae);
164    }
165
166    final ASN1Element[] entryElements = entrySequence.elements();
167    if (entryElements.length != 2)
168    {
169      throw new LDAPException(ResultCode.DECODING_ERROR,
170                              ERR_PRE_READ_RESPONSE_INVALID_ELEMENT_COUNT.get(
171                                   entryElements.length));
172    }
173
174    final String dn =
175         ASN1OctetString.decodeAsOctetString(entryElements[0]).stringValue();
176
177    final ASN1Sequence attrSequence;
178    try
179    {
180      attrSequence = ASN1Sequence.decodeAsSequence(entryElements[1]);
181    }
182    catch (final ASN1Exception ae)
183    {
184      Debug.debugException(ae);
185      throw new LDAPException(ResultCode.DECODING_ERROR,
186                     ERR_PRE_READ_RESPONSE_ATTRIBUTES_NOT_SEQUENCE.get(ae), ae);
187    }
188
189    final ASN1Element[] attrElements = attrSequence.elements();
190    final Attribute[] attrs = new Attribute[attrElements.length];
191    for (int i=0; i < attrElements.length; i++)
192    {
193      try
194      {
195        attrs[i] =
196             Attribute.decode(ASN1Sequence.decodeAsSequence(attrElements[i]));
197      }
198      catch (final ASN1Exception ae)
199      {
200        Debug.debugException(ae);
201        throw new LDAPException(ResultCode.DECODING_ERROR,
202                       ERR_PRE_READ_RESPONSE_ATTR_NOT_SEQUENCE.get(ae), ae);
203      }
204    }
205
206    entry = new ReadOnlyEntry(dn, attrs);
207  }
208
209
210
211  /**
212   * {@inheritDoc}
213   */
214  @Override()
215  public PreReadResponseControl
216              decodeControl(final String oid, final boolean isCritical,
217                            final ASN1OctetString value)
218         throws LDAPException
219  {
220    return new PreReadResponseControl(oid, isCritical, value);
221  }
222
223
224
225  /**
226   * Extracts a pre-read response control from the provided result.
227   *
228   * @param  result  The result from which to retrieve the pre-read response
229   *                 control.
230   *
231   * @return  The pre-read response control contained in the provided result, or
232   *          {@code null} if the result did not contain a pre-read response
233   *          control.
234   *
235   * @throws  LDAPException  If a problem is encountered while attempting to
236   *                         decode the pre-read response control contained in
237   *                         the provided result.
238   */
239  public static PreReadResponseControl get(final LDAPResult result)
240         throws LDAPException
241  {
242    final Control c = result.getResponseControl(PRE_READ_RESPONSE_OID);
243    if (c == null)
244    {
245      return null;
246    }
247
248    if (c instanceof PreReadResponseControl)
249    {
250      return (PreReadResponseControl) c;
251    }
252    else
253    {
254      return new PreReadResponseControl(c.getOID(), c.isCritical(),
255           c.getValue());
256    }
257  }
258
259
260
261  /**
262   * Encodes the provided information into an octet string that can be used as
263   * the value for this control.
264   *
265   * @param  entry  The entry to include in this pre-read response control.  It
266   *                must not be {@code null}.
267   *
268   * @return  An ASN.1 octet string that can be used as the value for this
269   *          control.
270   */
271  private static ASN1OctetString encodeValue(final ReadOnlyEntry entry)
272  {
273    Validator.ensureNotNull(entry);
274
275    final Collection<Attribute> attrs = entry.getAttributes();
276    final ArrayList<ASN1Element> attrElements = new ArrayList<>(attrs.size());
277    for (final Attribute a : attrs)
278    {
279      attrElements.add(a.encode());
280    }
281
282    final ASN1Element[] entryElements =
283    {
284      new ASN1OctetString(entry.getDN()),
285      new ASN1Sequence(attrElements)
286    };
287
288    return new ASN1OctetString(new ASN1Sequence(entryElements).encode());
289  }
290
291
292
293  /**
294   * Retrieves a read-only copy of the entry returned by this post-read response
295   * control.
296   *
297   * @return  A read-only copy of the entry returned by this post-read response
298   *          control.
299   */
300  public ReadOnlyEntry getEntry()
301  {
302    return entry;
303  }
304
305
306
307  /**
308   * {@inheritDoc}
309   */
310  @Override()
311  public String getControlName()
312  {
313    return INFO_CONTROL_NAME_PRE_READ_RESPONSE.get();
314  }
315
316
317
318  /**
319   * {@inheritDoc}
320   */
321  @Override()
322  public void toString(final StringBuilder buffer)
323  {
324    buffer.append("PreReadResponseControl(entry=");
325    entry.toString(buffer);
326    buffer.append(", isCritical=");
327    buffer.append(isCritical());
328    buffer.append(')');
329  }
330}