phpldapadmin/schema_functions.php

<?php

/*
 * Represents an attribute internal to an ObjectClass.
 */

 class ObjectClassAttribute
 {
 	/* This Attribute's name */
	var $name;
	/* This Attribute's root */
	var $source;

	function ObjectClassAttribute ($name, $source)
	{
	 $this->name=$name;
	 $this->source=$source;
	}

	/* getters */

	function getName ()
	{
	 return $this->name;
	}

	function getSource ()
	{
	 return $this->source;
	}
 }

/*
 * Represents an LDAP objectClass
 */
class ObjectClass
{
	/* This objectClass' OID, ie "2.16.840.1.113730.3.2.2" */
	var $oid;
	/* This objectClass' name, ie "inetOrgPerson" */
	var $name;
	/* This objectClass' description */
	var $description;
	/* array of objectClass names from which this objectClass inherits */
	var $sup_classes;
	/* one of STRUCTURAL, ABSTRACT, or AUXILIARY */
	var $type;
	/* arrays of attribute names that this objectClass requires */
	var $must_attrs;
	/* arrays of attribute names that this objectClass allows, but does not require */
	var $may_attrs;
	/* boolean value indicating whether this objectClass is obsolete */
	var $is_obsolete;

	/* Initialize the class' member variables */
	function initVars()
	{
		$this->oid = null;
		$this->name = null;
		$this->description = null;
		$this->sup_classes = array();
		$this->type = null;
		$this->must_attrs = array();
		$this->may_attrs = array();
		$this->is_obsolete = false;
	}

	/*
	 * Parses a raw LDAP objectClass string into this object's $this vars
	 */
	function ObjectClass( $raw_ldap_schema_string )
	{
		$this->initVars();
		$class = $raw_ldap_schema_string;
		$strings = preg_split ("/[\s,]+/", $class, -1,PREG_SPLIT_DELIM_CAPTURE);
		for($i=0; $i<count($strings); $i++) {
			switch($strings[$i]) {
				case '(':
					break;
				case 'NAME':
					if($strings[$i+1]!="(") {
						do {
							$i++;
							if(strlen($this->name)==0)
								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						}while(!preg_match("/\'$/s", $strings[$i]));
					} else {
						$i++;
						do {
							$i++;
							if(strlen($this->name) == 0)
 								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						} while(!preg_match("/\'$/s", $strings[$i]));
						do {
							$i++;
						}while($strings[$i]!=")");
					}
					$this->name =        preg_replace("/^\'/", "", $this->name);
					$this->name =        preg_replace("/\'$/", "", $this->name);
					break;
				case 'DESC':
					do {
						$i++;
						if(strlen($this->description)==0)
							$this->description=$this->description . $strings[$i];
						else
							$this->description=$this->description . " " . $strings[$i];
					}while(!preg_match("/\'$/s", $strings[$i]));
					break;
				case 'OBSOLETE':
					$this->is_obsolete = TRUE;
					break;
				case 'SUP':
					if($strings[$i+1]!="(") {
						$i++;
						array_push ($this->sup_classes, $strings[$i]);
					}else{
						$i++;
						do {
							$i++;
							if($strings[$i]!="$")
								array_push( $this->sup_classes, $strings[$i] );
						}while($strings[$i+1]!=")");
					}
					break;
				case 'ABSTRACT':
					$this->type='abstract';
					break;
				case 'STRUCTURAL':
					$this->type='structural';
					break;
				case 'AUXILIARY':
					$this->type='auxiliary';
					break;
				case 'MUST':
					if($strings[$i+1]!="(")
					{
						$i++;
						$attr = new ObjectClassAttribute($strings[$i], $this->name);
						array_push ($this->must_attrs, $attr);
					}else{
						$i++;
						do {
							$i++;
							if($strings[$i]!="$")
							{
							 $attr = new ObjectClassAttribute($strings[$i], $this->name);
							 array_push ($this->must_attrs, $attr);
							}
						}while($strings[$i+1]!=")");
					}
					sort($this->must_attrs);
					break;
				case 'MAY':
					if($strings[$i+1]!="(")
					{
						$i++;
						$attr = new ObjectClassAttribute($strings[$i], $this->name);
						array_push ($this->may_attrs, $attr);
					}else{
						$i++;
						do
						{
							$i++;
							if($strings[$i]!="$")
							{
							 $attr = new ObjectClassAttribute($strings[$i], $this->name);
							 array_push ($this->may_attrs, $attr);
							}
						}while($strings[$i+1]!=")");
					}
					sort($this->may_attrs);
					break;
				default:
					if(preg_match ("/[\d\.]+/i",$strings[$i]) && $i == 1)
						$this->oid = $strings[$i];
			}
		}

		$this->description = preg_replace("/^\'/", "", $this->description);
		$this->description = preg_replace("/\'$/", "", $this->description);
	}


	/* Getters */

	function getMustAttrs($oclasses = NULL)
	{
		$all_must_attrs = array();
		$all_must_attrs = $this->must_attrs;
		foreach( $this->sup_classes as $sup_class)
		{
			if( $oclasses != null
				&& $sup_class != "top" 
				&& isset( $oclasses[ strtolower($sup_class) ] ) ) {
						$sup_class = $oclasses[ strtolower($sup_class) ]; 
						$sup_class_must_attrs = $sup_class->getMustAttrs( $oclasses );
						$all_must_attrs = array_merge( $sup_class_must_attrs, $all_must_attrs );
			}
		}

		ksort($all_must_attrs);
		return $all_must_attrs;
	}

	function getMayAttrs($oclasses = NULL)
	{
		$all_may_attrs = array();
		$all_may_attrs = $this->may_attrs;
		foreach( $this->sup_classes as $sup_class_name )
		{
			if( $oclasses != null 
				&& $sup_class_name != "top" 
				&& isset( $oclasses[ strtolower($sup_class_name) ] ) ) {
					$sup_class = $oclasses[ strtolower($sup_class_name) ]; 
					$sup_class_may_attrs = $sup_class->getMayAttrs( $oclasses );
					$all_may_attrs = array_merge( $sup_class_may_attrs, $all_may_attrs );
			} 
		}

		ksort($all_may_attrs);
		return $all_may_attrs;
	}

	function getMustAttrNames( $oclasses = null )
	{
		$attrs = $this->getMustAttrs( $oclasses );
		$attr_names = array();
		foreach( $attrs as $attr )
			$attr_names[] = $attr->getName();
		return $attr_names;
	}

	function getMayAttrNames( $oclasses = null )
	{
		$attrs = $this->getMayAttrs( $oclasses );
		$attr_names = array();
		foreach( $attrs as $attr )
			$attr_names[] = $attr->getName();
		return $attr_names;
	}


	function getName()
	{
		return $this->name;
	}

	function getDescription()
	{
		return $this->description;
	}

	function getOID()
	{
		return $this->oid;
	}

	function getSupClasses()
	{
		return $this->sup_classes;
	}

	function getType()
	{
		return $this->type;
	}

	function getIsObsolete()
	{
		return $this->is_obsolete;
	}

	/*
	 * Adds the specified array of attributes to this objectClass' list of 
	 * MUST attributes. The resulting array of must attributes will contain
	 * unique members.
	 */
	function addMustAttrs( $new_must_attrs )
	{
		if( ! is_array( $new_must_attrs ) )
			return;
		if( 0 == count( $new_must_attrs ) )
			return;
		$this->must_attrs = array_values( array_unique( array_merge( $this->must_attrs, $new_must_attrs  ) ) );
	}

	/*
	 * Behaves identically to addMustAttrs, but it operates on the MAY
	 * attributes of this objectClass.
	 */
	function addMayAttrs( $new_may_attrs )
	{
		if( ! is_array( $new_may_attrs ) )
			return;
		if( 0 == count( $new_may_attrs ) )
			return;
		$this->may_attrs = array_values( array_unique( array_merge( $this->may_attrs, $new_may_attrs  ) ) );
	}

}

/*
 * Represents an LDAP AttributeType 
 */
class AttributeType
{
	/* The OID of this attributeType: ie, 1.2.3.4*/
	var $oid;
	/* The name of this attributeType */
	var $name;
	/* string: the description */
	var $description;
	/* boolean: is it obsoloete */
	var $is_obsolete;
	/* The attribute from which this attribute inherits (if any) */
	var $sup_attribute;
	/* The equality rule used */
	var $equality;
	/* The ordering of the attributeType */
	var $ordering;
	/* Boolean: supports substring matching? */
	var $sub_str;
	/* The full syntax string, ie 1.2.3.4{16} */
	var $syntax;
	/* boolean: is single valued only? */
	var $is_single_value;
	/* boolean: is collective? */
	var $is_collective;
	/* boolean: can use modify? */
	var $is_no_user_modification;
	/* The usage string set by the LDAP schema */
	var $usage;
	/* An array of alias attribute names, strings */
	var $aliases;
	/* The max number of characters this attribute can be */
	var $max_length;
	/* A string description of the syntax type (taken from the LDAPSyntaxes) */
	var $type;
	/* An array of objectClasses which use this attributeType (must be set by caller) */
	var $used_in_object_classes;

	/* 
	 * Initialize the class' member variables 
	 */
	function initVars()
	{
		$this->oid = null;
		$this->name = null;
		$this->description = null;
		$this->is_obsolete = false;
		$this->sup_attribute = null;
		$this->equality = null;
		$this->ordering = null;
		$this->sub_str = null;
		$this->syntax_oid = null;
		$this->syntax = null;
		$this->max_length = null;
		$this->is_single_value= null;
		$this->is_collective = false;
		$this->is_no_user_modification = false;
		$this->usage = null;
		$this->aliases = array();
		$this->type = null;
		$this->used_in_object_classes = array();
	}

	/*
	 * Parses a raw LDAP objectClass string into this object's $this vars
	 */
	function AttributeType( $raw_ldap_attr_string )
	{
		//echo "<nobr>$raw_ldap_attr_string</nobr><Br />";
		$this->initVars();
		$attr = $raw_ldap_attr_string;
		$strings = preg_split ("/[\s,]+/", $attr, -1,PREG_SPLIT_DELIM_CAPTURE);
		for($i=0; $i<count($strings); $i++) {
			switch($strings[$i]) {
				case '(':
					break;
				case 'NAME':
					if($strings[$i+1]!="(") {
						do {
							$i++;
							if(strlen($this->name)==0)
								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						}while(!preg_match("/\'$/s", $strings[$i]));
						// this attribute has no aliases
						$this->aliases = array();
					} else {
						$i++;
						do {
							$i++;
							if(strlen($this->name) == 0)
 								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						} while(!preg_match("/\'$/s", $strings[$i]));
						// add alias names for this attribute
						while($strings[++$i]!=")") {
							$alias = $strings[$i];
							$alias = preg_replace("/^\'/", "", $alias );
							$alias = preg_replace("/\'$/", "", $alias );
							$this->aliases[] = $alias;
						}
					}
					break;
				case 'DESC':
					do {
						$i++;
						if(strlen($this->description)==0)
							$this->description=$this->description . $strings[$i];
						else
							$this->description=$this->description . " " . $strings[$i];
					}while(!preg_match("/\'$/s", $strings[$i]));
					break;
				case 'OBSOLETE':
					$this->is_obsolete = TRUE;
					break;
				case 'SUP':
					$i++;
					$this->sup_attribute = $strings[$i];
					break;
				case 'EQUALITY':
					$i++;
					$this->equality = $strings[$i];
					break;
				case 'ORDERING':
					$i++;
					$this->ordering = $strings[$i];
					break;
				case 'SUBSTR':
					$i++;
					$this->sub_str = $strings[$i];
					break;
				case 'SYNTAX':
					$i++;
					$this->syntax = $strings[$i];
					$this->syntax_oid = preg_replace( "/{\d+}$/", "", $this->syntax );
					// does this SYNTAX string specify a max length (ie, 1.2.3.4{16})
					if( preg_match( "/{(\d+)}$/", $this->syntax, $this->max_length ) )
						$this->max_length = $this->max_length[1];
					else 
						$this->max_length = null;
					if($strings[$i+1]=="{")	{
						do {
							$i++;
							$this->name .= " " . $strings[$i];
						} while($strings[$i]!="}");
					}
					break;
				case 'SINGLE-VALUE':
					$this->is_single_value = TRUE;
					break;
				case 'COLLECTIVE':
					$this->is_collective = TRUE;
					break;
				case 'NO-USER-MODIFICATION':
					$this->is_no_user_modification = TRUE;
					break;
				case 'USAGE':
					$i++;
					$this->usage = $strings[$i];
					break;
				default:
					if(preg_match ("/[\d\.]+/i",$strings[$i]) && $i == 1)
						$this->oid = $strings[$i];
			}
		}

		$this->name =        preg_replace("/^\'/", "", $this->name);
		$this->name =        preg_replace("/\'$/", "", $this->name);
		$this->description = preg_replace("/^\'/", "", $this->description);
		$this->description = preg_replace("/\'$/", "", $this->description);
		$this->syntax_oid  = preg_replace("/^\'/", "", $this->syntax_oid );
		$this->syntax_oid  = preg_replace("/\'$/", "", $this->syntax_oid );
	}

	/* Getters */
	function getOID()
	{
		return $this->oid;
	}

	function getName()
	{
		return $this->name;
	}

	function getDescription()
	{
		return $this->description;
	}

	function getIsObsolete()
	{
		return $this->is_obsolete;
	}

	function getUsage()
	{
		return $this->usage;
	}

	function getSupAttribute()
	{
		return $this->sup_attribute;
	}

	function getEquality()
	{
		return $this->equality;
	}

	function getOrdering()
	{
		return $this->ordering;
	}

	function getSubstr()
	{
		return $this->sub_str;
	}

	function getAliases()
	{
		return $this->aliases;
	}

	/*
	 * Returns the entire raw syntax string for this attr, for example: 1.2.3.4{16}
	 */
	function getSyntaxString()
	{
		return $this->syntax;
	}

	/*
	 * Differs from getSyntaxString() in that it only returns the actual OID with any length
	 * specification removed. Ie, if the syntax string is 1.2.3.4{16}, this retruns
	 * 1.2.3.4. 
	 */
	function getSyntaxOID()
	{
		return $this->syntax_oid;
	}

	/*
	 * Returns the maximum length specified by this attribute (ie, "16" in 1.2.3.4{16})
	 */
	function getMaxLength()
	{
		return $this->max_length;
	}

	function getIsSingleValue()
	{
		return $this->is_single_value;
	}

	function setIsSingleValue( $is_single_value )
	{
		$this->is_single_value = $is_single_value;
	}


	function getIsCollective()
	{
		return $this->is_collective;
	}

	function getIsNoUserModification()
	{
		return $this->is_no_user_modification;
	}

	function getType()
	{
		return $this->type;
	}

	/*
	 * Removes an attribute name from the alias array.
	 */
	function removeAlias( $remove_alias_name )
	{
		foreach( $this->aliases as $i => $alias_name ) {
			if( 0 == strcasecmp( $alias_name, $remove_alias_name ) ) {
				unset( $this->aliases[ $i ] );
				$this->aliases = array_values( $this->aliases );
				return true;
			}
		}
		return false;
	}

	/*
	 * Adds an attribute name to the alias array.
	 */
	function addAlias( $new_alias_name )
	{
		$this->aliases[] = $new_alias_name;
	}

	function setName( $new_name )
	{
		$this->name = $new_name;
	}

	function setOID( $new_oid )
	{
		$this->oid = $new_oid;
	}

	function setDescription( $new_desc )
	{
		$this->description = $new_desc;
	}
	
	function setSupAttribute( $new_sup_attr )
	{
		$this->sup_attribute = $new_sup_attr;
	}

	function setAliases( $new_aliases )
	{
		$this->aliases = $new_aliases;
	}

	function setType( $new_type )
	{
		$this->type = $new_type;
	}

	function addUsedInObjectClass( $object_class_name )
	{
		foreach( $this->used_in_object_classes as $used_in_object_class )
			if( 0 == strcasecmp( $used_in_object_class, $object_class_name ) )
				return false;
		$this->used_in_object_classes[] = $object_class_name;
		return true;
	}

	function getUsedInObjectClasses()
	{
		return $this->used_in_object_classes;
	}
}

/*
 * Represents an LDAP Syntax
 */
class Syntax
{
	/* This Syntax OID, ie "2.16.840.1.113730.3.2.2" */
	var $oid;
	/* This Syntax description */
	var $description;

	/* Initialize the class' member variables */
	function initVars()
	{
		$this->oid = null;
		$this->description = null;
	}

	/*
	 * Parses a raw LDAP objectClass string into this object's $this vars
	 */
	function Syntax( $raw_ldap_syntax_string )
	{
		$this->initVars();
		$class = $raw_ldap_syntax_string;
		$strings = preg_split ("/[\s,]+/", $class, -1,PREG_SPLIT_DELIM_CAPTURE);
		for($i=0; $i<count($strings); $i++) {
			switch($strings[$i]) {
				case '(':
					break;
				case 'DESC':
					do {
						$i++;
						if(strlen($this->description)==0)
							$this->description=$this->description . $strings[$i];
						else
							$this->description=$this->description . " " . $strings[$i];
					}while(!preg_match("/\'$/s", $strings[$i]));
					break;
				default:
					if(preg_match ("/[\d\.]+/i",$strings[$i]) && $i == 1)
						$this->oid = $strings[$i];
			}
		}
		$this->description = preg_replace("/^\'/", "", $this->description);
		$this->description = preg_replace("/\'$/", "", $this->description);
	}


	/* Getters */

 	function getDescription()
	{
		return $this->description;
	}

	function getOID()
	{
		return $this->oid;
	}
}

/*
 * Represents an LDAP MatchingRule
 */
class MatchingRule
{
	/* This rule's OID, ie "2.16.840.1.113730.3.2.2" */
	var $oid;
	/* This rule's name */
	var $name;
	/* This rule's description */
	var $description;
	/* This rule's syntax OID */
	var $syntax;
	/* Boolean value indicating whether this MatchingRule is obsolete */
	var $is_obsolete;
	/* An array of attribute names who use this MatchingRule */
	var $used_by_attrs;

	/* Initialize the class' member variables */
	function initVars()
	{
		$this->oid = null;
		$this->name = null;
		$this->description = null;
		$this->is_obsolete = false;
		$this->syntax = null;
		$this->used_by_attrs = array();
	}

	/*
	 * Parses a raw LDAP objectClass string into this object's $this vars
	 */
	function MatchingRule( $raw_ldap_matching_rule_string )
	{
		$this->initVars();
		$strings = preg_split ("/[\s,]+/", $raw_ldap_matching_rule_string, -1,PREG_SPLIT_DELIM_CAPTURE);
		for($i=0; $i<count($strings); $i++) {
			switch($strings[$i]) {
				case '(':
					break;
				case 'NAME':
					if($strings[$i+1]!="(") {
						do {
							$i++;
							if(strlen($this->name)==0)
								$this->name = $strings[$i];
						else
								$this->name .= " " . $strings[$i];
						}while(!preg_match("/\'$/s", $strings[$i]));
					} else {
						$i++;
						do {
							$i++;
							if(strlen($this->name) == 0)
								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						} while(!preg_match("/\'$/s", $strings[$i]));
						do {
							$i++;
						}while($strings[$i]!=")");
					}
					$this->name =        preg_replace("/^\'/", "", $this->name);
					$this->name =        preg_replace("/\'$/", "", $this->name);
					break;
				case 'DESC':
					do {
						$i++;
						if(strlen($this->description)==0)
							$this->description=$this->description . $strings[$i];
						else
							$this->description=$this->description . " " . $strings[$i];
					}while(!preg_match("/\'$/s", $strings[$i]));
					break;
				case 'OBSOLETE':
					$this->is_obsolete = TRUE;
					break;
				case 'SYNTAX':
					$this->syntax = $strings[++$i];
					break;
				default:
					if(preg_match ("/[\d\.]+/i",$strings[$i]) && $i == 1)
						$this->oid = $strings[$i];
			}
		}
		$this->description = preg_replace("/^\'/", "", $this->description);
		$this->description = preg_replace("/\'$/", "", $this->description);
	}

	/*
	 * Sets the list of used_by_attrs to the array specified by $attrs;
	 */
	function setUsedByAttrs( $attrs )
	{
		$this->used_by_attrs = $attrs;
	}

	/*
	 * Adds an attribute name to the list of attributes who use this MatchingRule
	 * @return true if the attribute was added and false otherwise (already in the list)
	 */
	function addUsedByAttr( $new_attr_name )
	{
		foreach( $this->used_by_attrs as $attr_name )
			if( 0 == strcasecmp( $attr_name, $new_attr_name ) )
				return false;
		$this->used_by_attrs[] = $new_attr_name;
		return true;
	}

	/* Getters */

	function getName()
	{
		return $this->name;
	}

	function getDescription()
	{
		return $this->description;
	}

	function getIsObsolete()
	{
		return $this->is_obsolete;
	}

	function getSyntax()
	{
		return $this->description;
	}

	function getOID()
	{
		return $this->oid;
	}

	function getUsedByAttrs()
	{
		return $this->used_by_attrs;
	}
}

/*
 * Represents an LDAP schema matchingRuleUse entry
 */ 
class MatchingRuleUse
{
	/* The OID of the MatchingRule this applies to */
	var $oid;
	/* The name of the MathingRule this applies to */
	var $name;
	/* An array of attributeType names who make use of the mathingRule 
	 * identified by $this->oid and $this->name */
	var $used_by_attrs;

	/* Initialize the class' member variables */
	function initVars()
	{
		$this->oid = null;
		$this->name = null;
		$this->used_by_attrs = array();
	}

	function MatchingRuleUse( $raw_matching_rule_use_string )
	{
		$strings = preg_split ("/[\s,]+/", $raw_matching_rule_use_string, -1,PREG_SPLIT_DELIM_CAPTURE);
		for($i=0; $i<count($strings); $i++) {
			switch($strings[$i]) {
				case '(':
					break;
				case 'NAME':
					if($strings[$i+1]!="(") {
						do {
							$i++;
							if(strlen($this->name)==0)
								$this->name = $strings[$i];
						else
								$this->name .= " " . $strings[$i];
						}while(!preg_match("/\'$/s", $strings[$i]));
					} else {
						$i++;
						do {
							$i++;
							if(strlen($this->name) == 0)
								$this->name = $strings[$i];
							else
								$this->name .= " " . $strings[$i];
						} while(!preg_match("/\'$/s", $strings[$i]));
						do {
							$i++;
						}while($strings[$i]!=")");
					}
					$this->name =        preg_replace("/^\'/", "", $this->name);
					$this->name =        preg_replace("/\'$/", "", $this->name);
					break;
				case 'APPLIES':
					// TODO
					if($strings[$i+1]!="(") {
						// has a single attribute name
						$i++;
						$this->used_by_attrs = array( $strings[$i] );
						//echo "Adding single: " . $strings[$i] . "<br />";
					} else {
						// has multiple attribute names
						$i++;
						while($strings[$i]!=")") {
							$i++;
							$new_attr = $strings[$i];
							$new_attr = preg_replace("/^\'/", "", $new_attr );
							$new_attr = preg_replace("/\'$/", "", $new_attr );
							$this->used_by_attrs[] = $new_attr;
							//echo "Adding $new_attr<br />";
							$i++;
						}
					}
					break;
				default:
					if(preg_match ("/[\d\.]+/i",$strings[$i]) && $i == 1)
						$this->oid = $strings[$i];
			}
		}
		sort( $this->used_by_attrs );
	}

	/* Getters */

	function getOID()
	{
		return $this->oid;
	}

	function getName()
	{
		return $this->name;
	}

	function getUsedByAttrs()
	{
		return $this->used_by_attrs;
	}
}

/*
 * Helper for _get_raw_schema() which fetches the DN of the schema object
 * in an LDAP server based on a DN. Entries should set the subSchemaSubEntry
 * attribute pointing to the DN of the server schema. You can specify  the
 * DN whose subSchemaSubEntry you wish to retrieve of specify an empty string
 * to fetch the subScehamSubEntry from the Root DSE.
 */
function _get_schema_dn( $server_id, $dn, $debug=false )
{
	if( $debug ) echo "<pre>";
	$ds = pla_ldap_connect( $server_id );
	if( ! $ds )
		return false;

	$search = @ldap_read( $ds, $dn, 'objectClass=*', array( 'subschemaSubentry' ) );
	if( $debug ) { echo "Search result (ldap_read): "; var_dump( $search ); echo "\n"; }
	if( ! $search ) {
		if( $debug ) echo "_get_schema_dn() returning false. (search val is false)\n";
		return false;
	}

	if( ldap_count_entries( $ds, $search ) == 0 ) {
		if( $debug ) echo "_get_schema_dn() returning false (ldap_count_entries() == 0).\n";
		return false;
	}

	$entries = @ldap_get_entries( $ds, $search );
	if( $debug ) { echo "Entries (ldap_get_entries): "; var_dump( $entries ); echo "\n"; }
	if( ! $entries || ! is_array( $entries ) ) {
		if( $debug ) echo "_get_schema_dn() returning false (Bad entries val, false or not array).\n";
		return false;
	}

	$entry = isset( $entries[0] ) ? $entries[0] : false;
	if( ! $entry ) {
		if( $debug ) echo "_get_schema_dn() returning false (entry val is false)\n";
		return false;
	}

	$sub_schema_sub_entry = isset( $entry[0] ) ? $entry[0] : false;
	if( ! $sub_schema_sub_entry ) {
		if( $debug ) echo "_get_schema_dn() returning false (sub_schema_sub_entry val is false)\n";
		return false;
	}

	$schema_dn = isset( $entry[ $sub_schema_sub_entry ][0] ) ?
					$entry[ $sub_schema_sub_entry ][0] :
					false;

	if( $debug ) echo "_get_schema_dn() returning: \"" . $schema_dn . "\"\n";
	return $schema_dn;
}

/*
 * Fetches the raw schema array for the subschemaSubentry of the server. Note,
 * this function has grown many hairs to accomodate more LDAP servers. It is
 * needfully complicated. If you can find a better way to write it, feel free!
 *
 * @param $server_id - The server ID whose server you want to retrieve
 * @param $schema_to_fetch - A string indicating which type of schema to 
 *		fetch. Five valid values: 'objectclasses', 'attributetypes', 
 *		'ldapsyntaxes', 'matchingruleuse', or 'matchingrules'. 
 *		Case insensitive.
 * @param $dn (optional) This paremeter is the DN of the entry whose schema you
 * 		would like to fetch. Entries have the option of specifying
 * 		their own subschemaSubentry that points to the DN of the system
 * 		schema entry which applies to this attribute. If unspecified,
 *		this will try to retrieve the schema from the RootDSE subschemaSubentry.
 *		Failing that, we use some commonly known schema DNs. Default 
 *		value is the Root DSE DN (zero-length string)
 * @return an array of strings of this form:
 *    Array (
 *      [0] => "( 1.3.6.1.4.1.7165.1.2.2.4 NAME 'gidPool' DESC 'Pool ...
 *      [1] => "( 1.3.6.1.4.1.7165.2.2.3 NAME 'sambaAccount' DESC 'Sa ...
 *      etc.
 */
function _get_raw_schema( $server_id, $schema_to_fetch, $dn='' )
{
	global $lang;
	static $cache = null;

	// Swith to true to enable verbose output of schema fetching progress
	$debug = false;

	$ds = pla_ldap_connect( $server_id );
	if( ! $ds )
		return false;

	// error checking
	$schema_to_fetch = strtolower( $schema_to_fetch );
	$valid_schema_to_fetch = array( 'objectclasses', 'attributetypes', 'ldapsyntaxes', 
					'matchingrules', 'matchingruleuse'  );
	if( ! in_array( $schema_to_fetch, $valid_schema_to_fetch ) )
		pla_error( "Bad parameter provided to function to _get_raw_schema(). '" 
				. htmlspecialchars( $schema_to_fetch ) . "' is 
				not valid for the schema_to_fetch parameter." );
	
	// Minimize the hits to LDAP server by caching the result
	if( isset( $cache[ $server_id ][ $schema_to_fetch ] ) )
		return $cache[ $server_id ][ $schema_to_fetch ];

	// Try to get the schema DN from the specified entry. 
	$schema_dn = _get_schema_dn( $server_id, $dn, $debug );

	// Do we need to try again with the Root DSE?
	if( ! $schema_dn )
		$schema_dn = _get_schema_dn( $server_id, '', $debug );

	// Store the eventual schema retrieval in $schema_search
	$schema_search = null;

	if( $schema_dn ) {
		if( $debug ) { echo "Found the schema DN: "; var_dump( $schema_dn ); echo "\n"; }
		$schema_search = @ldap_read( $ds, $schema_dn, '(objectClass=*)',
							array( $schema_to_fetch ), 0, 0, 0, 
							LDAP_DEREF_ALWAYS );
		if( $schema_search === false ) {
			if( $debug ) echo "Did not find the schema at DN: $schema_dn.\n";
			$schema_search = null;
			unset( $schema_dn );
		} else {
			if( $debug ) echo "Found the schema at DN: $schema_dn.\n";
		}
	} 

	// Second chance: If the DN or Root DSE didn't give us the subschemaSubentry, ie $schema_search
	// is still null, use some common subSchemaSubentry DNs as a work-around.

	if( $debug && $schema_search == null )
		echo "Attempting work-arounds for 'broken' LDAP servers...\n";

	// cn=subschema for OpenLDAP
	if( $schema_search == null ) {
		if( $debug ) echo "Attempting with cn=subschema (OpenLDAP)...\n";
		// try with the standard DN
		$schema_search = @ldap_read($ds, 'cn=subschema', '(objectClass=*)',
				array( $schema_to_fetch ), 0, 0, 0, LDAP_DEREF_ALWAYS );
	}

	// cn=schema for Novell eDirectory
	if( $schema_search == null ) {
		if( $debug ) echo "Attempting with cn=schema (Novell)...\n";
		// try again, with a different schema DN
		$schema_search = @ldap_read($ds, 'cn=schema', '(objectClass=*)',
				array( $schema_to_fetch ), 0, 0, 0, LDAP_DEREF_ALWAYS );
	}

	// cn=schema,cn=configuration,dc=example,dc=com for ActiveDirectory
	if( $schema_search == null ) {
		// try again, with a different schema DN
		global $servers;
		$base_dn = isset( $servers[ $server_id ][ 'base' ] ) ?
				$servers[ $server_id ][ 'base' ] :
				null;
		if( $debug ) echo "Attempting with cn=schema,cn=configuration,$base_dn (ActiveDirectory)...\n";
		if( $base_dn != null )
			$schema_search = @ldap_read($ds, 'cn=schema,cn=configuration,' . $base_dn, '(objectClass=*)',
				array( $schema_to_fetch ), 0, 0, 0, LDAP_DEREF_ALWAYS );
	}

	// cn=Schema,ou=Admin,dc=example,dc=com for SiteServer
	if( $schema_search == null ) {
		// try again, with a different schema DN
		global $servers;
		$base_dn = isset( $servers[ $server_id ][ 'base' ] ) ?
				$servers[ $server_id ][ 'base' ] :
				null;
		if( $debug ) echo "Attempting with cn=Schema,ou=Admin,$base_dn (ActiveDirectory)...\n";
		if( $base_dn != null )
			$schema_search = @ldap_read($ds, 'cn=Schema,ou=Admin,' . $base_dn, '(objectClass=*)',
				array( $schema_to_fetch ), 0, 0, 0, LDAP_DEREF_ALWAYS );
	}

	// Shall we just give up?
	if( $schema_search == null ) 
		return false;

	// Did we get something unrecognizable?
	if( 'resource' != gettype( $schema_search ) ) {
		if( $debug ) "Returning false since schema_esarch is not of type 'resource'\n";
		return false;
	}
	
	$schema = @ldap_get_entries( $ds, $schema_search );
	if( $schema == false ) {
		if( $debug ) "Returning false since ldap_get_entries() returned false.\n";
		return false;
	}

	// Make a nice array of this form:
	// Array (
	//    [0] => "( 1.3.6.1.4.1.7165.1.2.2.4 NAME 'gidPool' DESC 'Pool ...
	//    [1] => "( 1.3.6.1.4.1.7165.2.2.3 NAME 'sambaAccount' DESC 'Sa ...
	//    etc.
	if( ! isset( $schema[0][$schema_to_fetch] ) ) {
		if( $debug ) "Returning false since '$schema_to_fetch' isn't in the schema array\n";
		return false;
	}

	$schema = $schema[0][$schema_to_fetch];
	unset( $schema['count'] );

	// Store the results in cache for subsequent calls
	$cache[ $server_id ][ $schema_to_fetch ] = $schema;

	return $schema;
}

/* 
 * Returns an associative array of objectClasses for the specified 
 * $server_id. Each array entry's key is the name of the objectClass
 * in lower-case. 
 * The sub-entries consist of sub-arrays called 'must_attrs' and 
 * 'may_attrs', and sub-entries called 'oid', 'name' and 'description'.
 */
function get_schema_objectclasses( $server_id, $dn=null )
{
	// cache the schema to prevent multiple schema fetches from LDAP server
	static $cache = array();
	if( isset( $cache[$server_id] ) ) {
		//echo "Using oclass cache.<br />";
		return $cache[$server_id];
	}

	$raw_oclasses = _get_raw_schema( $server_id, 'objectclasses', $dn );
	if( ! $raw_oclasses )
		return false;

	// build the array of objectClasses
	$object_classes = array();
	foreach( $raw_oclasses as $class_string  ) {
		if( $class_string == null || 0 == strlen( $class_string ) )
			continue;
		$object_class = new ObjectClass( $class_string );
		$name = $object_class->getName();
		$key = strtolower( $name );
		$object_classes[ $key ] = $object_class;
	}

	ksort( $object_classes );

	// cache the schema to prevent multiple schema fetches from LDAP server
	$cache[ $server_id ] = $object_classes;
	return( $object_classes );
}

/*
 * Returns the schema for a single ObjectClass
 */
function get_schema_objectclass( $server_id, $oclass_name, $dn=null )
{
	$oclass_name = strtolower( $oclass_name );
	$oclasses = get_schema_objectclasses( $server_id, $dn );
	if( ! $oclasses )
		return false;
	if( isset( $oclasses[ $oclass_name ] ) )
		return $oclasses[ $oclass_name ];
	else
		return false;
}

/*
 * Retrieves the schema for a single attribute.
 */
function get_schema_attribute( $server_id, $attr_name, $dn=null ) 
{
	$attr_name = real_attr_name( $attr_name );
	$schema_attrs = get_schema_attributes( $server_id, $dn );
	$attr_name = strtolower( $attr_name );
	$schema_attr = isset( $schema_attrs[ $attr_name ] ) ?
				$schema_attrs[ $attr_name ] :
				false;
	return $schema_attr;
}

/* 
 * Returns an array of AttributeType objects for the specified 
 * $server_id. Each array entry's key is the name of the attribute,
 * in lower-case.
 */
function get_schema_attributes( $server_id, $dn = null )
{
	// Cache gets filled in later (bottom). each subsequent call uses
	// the cache which has the attributes already fetched and parsed
	static $cache = null;
	if( isset( $cache[ $server_id ] ) )
		return $cache[ $server_id ];

	$raw_attrs = _get_raw_schema( $server_id, 'attributeTypes', $dn );
	if( ! $raw_attrs )
		return false;
	
	// build the array of attribueTypes
	$syntaxes = get_schema_syntaxes( $server_id, $dn );
	$attrs = array();
	foreach( $raw_attrs as $attr_string ) {
		if( $attr_string == null || 0 == strlen( $attr_string ) )
			continue;
		$attr = new AttributeType( $attr_string );
		if( isset( $syntaxes[ $attr->getSyntaxOID() ] ) ) {
			$syntax = $syntaxes[ $attr->getSyntaxOID() ];
			$attr->setType( $syntax->getDescription() );
		}
		$name = $attr->getName();
		$key = strtolower( $name );
		$attrs[ $key ] = $attr;
	}

	add_aliases_to_attrs( $attrs );
	add_sup_to_attrs( $attrs );

	ksort( $attrs );

	// cache the schema to prevent multiple schema fetches from LDAP server
	$cache[ $server_id ] = $attrs;
	return( $attrs );
}

/*
 * For each attribute that has multiple names, this function adds unique entries to 
 * the attrs array for those names. Ie, attributeType has name 'gn' and 'givenName'.
 * This function will create a unique entry for 'gn' and 'givenName'.
 */
function add_aliases_to_attrs( &$attrs )
{
	// go back and add data from aliased attributeTypes
	foreach( $attrs as $name => $attr ) {
		$aliases = $attr->getAliases();
		if( is_array( $aliases ) &&  count( $aliases ) > 0 ) {
			// foreach of the attribute's aliases, create a new entry in the attrs array
			// with its name set to the alias name, and all other data copied
			foreach( $aliases as $alias_attr_name ) {
				$new_attr = $attr;
				$new_attr->setName( $alias_attr_name );
				$new_attr->addAlias( $attr->getName() );
				$new_attr->removeAlias( $alias_attr_name );
				$new_attr_key = strtolower( $alias_attr_name );
				$attrs[ $new_attr_key ] = $new_attr;
			}
		}
	}
}

/*
 * Adds inherited values to each attributeType specified by the SUP directive. 
 * Supports infinite levels of inheritance.
 */
function add_sup_to_attrs( &$attrs )
{
	$debug = false;
	if( $debug ) echo "<pre>";

	if( $debug ) print_r( $attrs );
	
	// go back and add any inherited descriptions from parent attributes (ie, cn inherits name)
	foreach( $attrs as $key => $attr ) {
		if( $debug ) echo "Analyzing inheritance for attribute '" . $attr->getName() . "'\n";
		$sup_attr_name = $attr->getSupAttribute();
		$sup_attr = null;

		// Does this attribute have any inheritance happening here?
		if( null != trim( $sup_attr_name ) ) {

			// This loop really should traverse infinite levels of inheritance (SUP) for attributeTypes,
			// but just in case we get carried away, stop at 100. This shouldn't happen, but for
			// some weird reason, we have had someone report that it has happened. Oh well.
			$i = 0;
			while( $i++ < 100 /* 100 == INFINITY ;) */ ) {
				if( $debug ) echo "Top of loop.\n";

				if( ! isset( $attrs[ strtolower( $sup_attr_name ) ] ) ){ 
					pla_error( "Schema error: attributeType '" . $attr->getName() . "' inherits from 
								'" . $sup_attr_name . "', but attributeType '" . $sup_attr_name . "' does not
								exist." );
						return;
				}

				if( $debug ) echo " sup_attr_name: $sup_attr_name\n";
				$sup_attr = $attrs[ strtolower( $sup_attr_name ) ];
				if( $debug ) echo " Sup attr: " . $sup_attr->getName() . "\n";

				$sup_attr_name = $sup_attr->getSupAttribute();
				if( $debug ) echo " Does the sup attr itself have a sup attr?\n";

				// Does this superior attributeType not have a superior attributeType?
				if( null == $sup_attr_name || strlen( trim( $sup_attr_name ) ) == 0 ) {

					// Since this attribute's superior attribute does not have another superior
					// attribute, clone its properties for this attribute. Then, replace
					// those cloned values with those that can be explicitly set by the child
					// attribute attr). Save those few properties which the child can set here:
					if( $debug ) echo "  nope, this is the end of the inheritance chain after $i iterations.\n";
					$tmp_name = $attr->getName();
					$tmp_oid = $attr->getOID();
					$tmp_sup = $attr->getSupAttribute();
					$tmp_aliases = $attr->getAliases();
					$tmp_single_val = $attr->getIsSingleValue();


					if( $debug ) {
						echo "  populating values into attribute from sup attribute:\n";
						echo "Before: ";
						print_r( $attr );
					}

					// clone the SUP attributeType and populate those values
					// that were set by the child attributeType
					$attr = $sup_attr;
					$attr->setOID( $tmp_oid );
					$attr->setName( $tmp_name );
					$attr->setSupAttribute( $tmp_sup);
					$attr->setAliases( $tmp_aliases );

					if( $debug ) {
						echo "After (name, sup_attr, and aliases should not have changed!: ";
						print_r( $attr );
					}
					// only overwrite the SINGLE-VALUE property if the child explicitly sets it
					// (note: All LDAP attributes default to multi-value if not explicitly set SINGLE-VALUE)
					if( true == $tmp_single_val )
						$attr->setIsSingleValue( true );

					// replace this attribute in the attrs array now that we have populated
					// new values therein
					$attrs[$key] = $attr;

					// very important: break out after we are done with this attribute
					$sup_attr_name = null;
					$sup_attr = null;
					break;

				} else {

					// do nothing, move on down the chain of inheritance...
					if( $debug ) echo "  yup, march down the inheritance chain (iteration $i).\n";
					if( $debug ) { echo "  The sup attr is: "; var_dump( $sup_attr_name ); echo "\n"; }

				}
			}
		}
	}

	if( $debug ) echo "</pre>\n";
}

/* 
 * Returns an array of MatchingRule objects for the specified server.
 * The key of each entry is the OID of the matching rule.
 */
function get_schema_matching_rules( $server_id, $dn=null )
{
	static $cache;

	// cache the schema to prevent multiple schema fetches from LDAP server
	if( isset( $cache[$server_id] ) ) {
		return $cache[$server_id];
	}

	// build the array of MatchingRule objects
	$raw_matching_rules = _get_raw_schema( $server_id, 'matchingRules', $dn );
	if( ! $raw_matching_rules )
		return false;
	$rules = array();
	foreach( $raw_matching_rules as $rule_string ) {
		if( $rule_string == null || 0 == strlen( $rule_string ) )
			continue;
		$rule = new MatchingRule( $rule_string );
		$key = strtolower( $rule->getName() );
		$rules[ $key ] = $rule;
	}

	ksort( $rules );

	// For each MatchingRuleUse entry, add the attributes who use it to the
	// MatchingRule in the $rules array.
	$raw_matching_rule_use = _get_raw_schema( $server_id, 'matchingRuleUse' );
	if( $raw_matching_rule_use != false ) {
		foreach( $raw_matching_rule_use as $rule_use_string ) {
			if( $rule_use_string == null || 0 == strlen( $rule_use_string ) )
				continue;
			$rule_use = new MatchingRuleUse( $rule_use_string );
			$key = strtolower( $rule_use->getName() );
			if( isset( $rules[ $key ] ) )
				$rules[ $key ]->setUsedByAttrs( $rule_use->getUsedByAttrs() );
		}
	} else {
		// No MatchingRuleUse entry in the subschema, so brute-forcing
		// the reverse-map for the "$rule->getUsedByAttrs()" data.
		$attrs = get_schema_attributes( $server_id, $dn );
		if( is_array( $attrs ) )
			foreach( $attrs as $attr ) {
				$rule_key = strtolower( $attr->getEquality() );
				if( isset( $rules[ $rule_key ] ) )
					$rules[ $rule_key ]->addUsedByAttr( $attr->getName() );
			}
	}

	// cache the schema to prevent multiple schema fetches from LDAP server
	$cache[$server_id] = $rules;
	return $rules;
}

/* 
 * Returns an array of Syntax objects that this LDAP server uses mapped to
 * their descriptions. The key of each entry is the OID of the Syntax.
 */
function get_schema_syntaxes( $server_id, $dn=null )
{
	static $cache;

	// cache the schema to prevent multiple schema fetches from LDAP server
	if( isset( $cache[$server_id] ) ) {
		return $cache[$server_id];
	}

	$raw_syntaxes = _get_raw_schema( $server_id, 'ldapSyntaxes', $dn );
	if( ! $raw_syntaxes )
		return false;

	// build the array of attributes
	$syntaxes = array();
	foreach( $raw_syntaxes as $syntax_string ) {
		$syntax = new Syntax( $syntax_string );
		$key = strtolower( trim( $syntax->getOID() ) );
		if( ! $key ) continue;
		$syntaxes[$key] = $syntax;
	}

	ksort( $syntaxes );

	// cache the schema to prevent multiple schema fetches from LDAP server
	$cache[$server_id] = $syntaxes;

	return $syntaxes;
}

?>