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 *    http://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.shared.ldap.model.schema.syntaxCheckers;
021
022
023import org.apache.directory.shared.ldap.model.constants.SchemaConstants;
024import org.apache.directory.shared.ldap.model.schema.SyntaxChecker;
025import org.apache.directory.shared.util.Strings;
026import org.slf4j.Logger;
027import org.slf4j.LoggerFactory;
028
029
030/**
031 * A SyntaxChecker which verifies that a value is a TeletexTerminalIdentifier according to 
032 * RFC 4517 :
033 * 
034 * teletex-id = ttx-term *(DOLLAR ttx-param)
035 * ttx-term   = PrintableString          ; terminal identifier
036 * ttx-param  = ttx-key COLON ttx-value  ; parameter
037 * ttx-key    = "graphic" | "control" | "misc" | "page" | "private"
038 * ttx-value  = *ttx-value-octet
039 *
040 * ttx-value-octet = %x00-23 | (%x5C "24") | %x25-5B | (%x5C "5C") | %x5D-FF
041 * 
042 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
043 */
044@SuppressWarnings("serial")
045public class TeletexTerminalIdentifierSyntaxChecker extends SyntaxChecker
046{
047    /** A logger for this class */
048    private static final Logger LOG = LoggerFactory.getLogger( TeletexTerminalIdentifierSyntaxChecker.class );
049
050    /**
051     * Creates a new instance of TeletexTerminalIdentifier.
052     */
053    public TeletexTerminalIdentifierSyntaxChecker()
054    {
055        super( SchemaConstants.TELETEX_TERMINAL_IDENTIFIER_SYNTAX );
056    }
057    
058    
059    /**
060     * {@inheritDoc}
061     */
062    public boolean isValidSyntax( Object value )
063    {
064        String strValue = null;
065
066        if ( value == null )
067        {
068            LOG.debug( "Syntax invalid for 'null'" );
069            return false;
070        }
071        
072        if ( value instanceof String )
073        {
074            strValue = ( String ) value;
075        }
076        else if ( value instanceof byte[] )
077        {
078            strValue = Strings.utf8ToString((byte[]) value);
079        }
080        else
081        {
082            strValue = value.toString();
083        }
084
085        if ( strValue.length() == 0 )
086        {
087            LOG.debug( "Syntax invalid for '{}'", value );
088            return false;
089        }
090
091        // Search for the first '$' separator
092        int dollar = strValue.indexOf( '$' );
093        
094        String terminalIdentifier = ( ( dollar == -1 ) ? strValue : strValue.substring( 0, dollar ) );
095        
096        if ( terminalIdentifier.length() == 0 )
097        {
098            // It should not be null
099            LOG.debug( "Syntax invalid for '{}'", value );
100            return false;
101        }
102        
103        if ( !Strings.isPrintableString(terminalIdentifier) )
104        {
105            // It's not a valid PrintableString 
106            LOG.debug( "Syntax invalid for '{}'", value );
107            return false;
108        }
109        
110        if ( dollar == -1 )
111        {
112            // No ttx-param : let's get out
113            LOG.debug( "Syntax valid for '{}'", value );
114            return true;
115        }
116        
117        // Ok, now let's deal withh optional ttx-params
118        String[] ttxParams = strValue.substring( dollar + 1 ).split( "\\$" );
119        
120        if ( ttxParams.length == 0 )
121        {
122            LOG.debug( "Syntax invalid for '{}'", value );
123            return false;
124        }
125        
126        for ( String ttxParam:ttxParams )
127        {
128            int colon = ttxParam.indexOf( ':' );
129            
130            if ( colon == -1 )
131            {
132                // we must have a ':' separator
133                LOG.debug( "Syntax invalid for '{}'", value );
134                return false;
135            }
136            
137            String key = ttxParam.substring( 0, colon );
138            
139            if ( key.startsWith( "graphic" )
140                || key.startsWith( "control" )
141                || key.startsWith( "misc" )
142                || key.startsWith( "page" )
143                || key.startsWith( "private" ) )
144            {
145                if ( colon + 1 == ttxParam.length() )
146                {
147                    LOG.debug( "Syntax invalid for '{}'", value );
148                    return false;
149                }
150                
151                boolean hasEsc = false;
152                
153                for ( byte b: Strings.getBytesUtf8(ttxParam) )
154                {
155                    switch ( b )
156                    {
157                        case 0x24 :
158                            // '$' is not accepted
159                            LOG.debug( "Syntax invalid for '{}'", value );
160                            return false;
161                            
162                        case 0x5c :
163                            if ( hasEsc )
164                            {
165                                // two following \ are not accepted
166                                LOG.debug( "Syntax invalid for '{}'", value );
167                                return false;
168                            }
169                            else
170                            {
171                                hasEsc = true;
172                            }
173                            
174                            continue;
175                        
176                        case '2' :
177                            continue;
178
179                        case '4' :
180                            // We have found a "\24"
181                            hasEsc = false;
182                            continue;
183                            
184                        case '5' :
185                            continue;
186
187                        case 'c' :
188                        case 'C' :
189                            // We have found a "\5c" or a "\5C"
190                            hasEsc = false;
191                            continue;
192                            
193                        default :
194                            if ( hasEsc )
195                            {
196                                // A \ should be followed by "24" or "5c" or "5C"
197                                return false;
198                            }
199                            
200                        continue;
201                    }
202                }
203            }
204            else
205            {
206                LOG.debug( "Syntax invalid for '{}'", value );
207                return false;
208            }
209        }
210        
211        LOG.debug( "Syntax valid for '{}'", value );
212        return true;
213    }
214}