php man page for ldap_compare

LDAP_COMPARE(3) 							 1							   LDAP_COMPARE(3)

ldap_compare - Compare value of attribute found in entry specified with DN

SYNOPSIS
       mixed ldap_compare (resource  $link_identifier, string  $dn, string  $attribute, string	$value)

DESCRIPTION
	Compare $value of $attribute with value of same attribute in an LDAP directory entry.

PARAMETERS
	      o $link_identifier
		- An LDAP link identifier, returned by ldap_connect(3).

	      o $dn
		- The distinguished name of an LDAP entity.

	      o $attribute
		- The attribute name.

	      o $value
		- The compared value.

RETURN VALUES
	Returns TRUE if $value matches otherwise returns FALSE. Returns -1 on error.

EXAMPLES
	The following example demonstrates how to check whether or not given password matches the one defined in DN specified entry.

       Example #1

	      Complete example of password check

	      <?php

	      $ds=ldap_connect("localhost");  // assuming the LDAP server is on this host

	      if ($ds) {

		  // bind
		  if (ldap_bind($ds)) {

		      // prepare data
		      $dn = "cn=Matti Meikku, ou=My Unit, o=My Company, c=FI";
		      $value = "secretpassword";
		      $attr = "password";

		      // compare value
		      $r=ldap_compare($ds, $dn, $attr, $value);

		      if ($r === -1) {
			  echo "Error: " . ldap_error($ds);
		      } elseif ($r === true) {
			  echo "Password correct.";
		      } elseif ($r === false) {
			  echo "Wrong guess! Password incorrect.";
		      }

		  } else {
		      echo "Unable to bind to LDAP server.";
		  }

		  ldap_close($ds);

	      } else {
		  echo "Unable to connect to LDAP server.";
	      }
	      ?>

NOTES
       Warning

	      ldap_compare(3) can NOT be used to compare BINARY values!

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