001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * https://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.directory.api.ldap.codec.api; 021 022 023import java.io.InputStream; 024import java.nio.ByteBuffer; 025 026import org.apache.directory.api.asn1.DecoderException; 027import org.apache.directory.api.asn1.ber.Asn1Decoder; 028import org.apache.directory.api.asn1.ber.tlv.TLVStateEnum; 029import org.apache.directory.api.i18n.I18n; 030import org.apache.directory.api.ldap.model.message.Message; 031import org.slf4j.Logger; 032import org.slf4j.LoggerFactory; 033 034 035/** 036 * The LdapDecoder decodes ASN.1 BER encoded PDUs into LDAP messages 037 * 038 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 039 */ 040public class LdapDecoder 041{ 042 /** The logger */ 043 private static final Logger LOG = LoggerFactory.getLogger( LdapDecoder.class ); 044 045 /** The name of the LdapSession's attribute for the LDAP container used during the decoding */ 046 public static final String MESSAGE_CONTAINER_ATTR = "LDAP-container"; 047 048 /** The maximum PDU size, stored into the LDAPSession's attribute */ 049 public static final String MAX_PDU_SIZE_ATTR = "LDAP-maxPduSize"; 050 051 052 /** 053 * Creates an instance of a Ldap Decoder implementation. 054 */ 055 public LdapDecoder() 056 { 057 } 058 059 060 /** 061 * Decodes a PDU from an input stream into a Ldap message container. We can only 062 * decode one complete message. 063 * 064 * @param in The input stream to read and decode PDU bytes from 065 * @param container The LdapMessageContainer containing the message to decode 066 * @return return The decoded message 067 * @throws DecoderException If the decoding failed 068 */ 069 public Message decode( InputStream in, LdapMessageContainer<? extends Message> container ) 070 throws DecoderException 071 { 072 try 073 { 074 int amount; 075 076 while ( in.available() > 0 ) 077 { 078 byte[] buf = new byte[in.available()]; 079 080 amount = in.read( buf ); 081 082 if ( amount == -1 ) 083 { 084 break; 085 } 086 087 Asn1Decoder.decode( ByteBuffer.wrap( buf, 0, amount ), container ); 088 } 089 } 090 catch ( Exception e ) 091 { 092 String message = I18n.err( I18n.ERR_05204_LDAP_DECODER_FAILURE, e.getLocalizedMessage() ); 093 LOG.error( message ); 094 throw new DecoderException( message, e ); 095 } 096 097 if ( container.getState() == TLVStateEnum.PDU_DECODED ) 098 { 099 if ( LOG.isDebugEnabled() ) 100 { 101 LOG.debug( I18n.msg( I18n.MSG_5200_DECODED_LDAP_MESSAGE, container ) ); 102 } 103 104 return container.getMessage(); 105 } 106 else 107 { 108 LOG.error( I18n.err( I18n.ERR_05205_PDU_DOES_NOT_CONTAIN_ENOUGH_DATA ) ); 109 throw new DecoderException( I18n.err( I18n.ERR_05206_INPUT_STREAM_TOO_SHORT_PDU ) ); 110 } 111 } 112}