LDAP Controls

Here are some examples of using LDAP Controls with PHP >= 7.3.0.

Example #1 Bind with policy information

<?php

$user   = 'cn=admin,dc=example,dc=com';
$passwd = 'adminpassword';

$ds = ldap_connect('ldap://localhost');

if ($ds) {
    $r = ldap_bind_ext($ds, $user, $passwd, [['oid' => LDAP_CONTROL_PASSWORDPOLICYREQUEST]]);

    if (ldap_parse_result($ds, $r, $errcode, $matcheddn, $errmsg, $referrals, $ctrls)) {
        if ($errcode != 0) {
            die("Error: $errmsg ($errcode)");
        }
        if (isset($ctrls[LDAP_CONTROL_PASSWORDPOLICYRESPONSE])) {
            $value = $ctrls[LDAP_CONTROL_PASSWORDPOLICYRESPONSE]['value'];
            echo "Expires in: ".$value['expire']." seconds\n";
            echo "Number of auth left: ".$value['grace']."\n";
            if (isset($value['error'])) {
                echo "Policy error code: ".$value['error'];
            }
        }
    }
} else {
    die("Unable to connect to LDAP server");
}
?>

Example #2 Modify description only if it's not empty

<?php
// $link is an LDAP connection

$result = ldap_mod_replace_ext(
    $link,
    'o=test,dc=example,dc=com',
    ['description' => 'New description'],
    [
        [
            'oid'         => LDAP_CONTROL_ASSERT,
            'iscritical'  => TRUE,
            'value'       => ['filter' => '(!(description=*))']
        ]
    ]
);

// Then use ldap_parse_result
?>

Example #3 Read some values before deletion

<?php
// $link is an LDAP connection

$result = ldap_delete_ext(
    $link,
    'o=test,dc=example,dc=com',
    [
        [
            'oid'         => LDAP_CONTROL_PRE_READ,
            'iscritical'  => TRUE,
            'value'       => ['attrs' => ['o', 'description']]
        ]
    ]
);

// Then use ldap_parse_result
?>

Example #4 Delete a reference

<?php
// $link is an LDAP connection

// Without the control it would delete the referenced node
// Make sure to set the control as critical to avoid that
$result = ldap_delete_ext(
    $link,
    'cn=reference,dc=example,dc=com',
    [['oid' => LDAP_CONTROL_MANAGEDSAIT, 'iscritical' => TRUE]]
);

// Then use ldap_parse_result
?>

Example #5 Use pagination for a search

<?php
// $link is an LDAP connection

$cookie = '';

do {
    $result = ldap_search(
        $link, 'dc=example,dc=base', '(cn=*)', ['cn'], 0, 0, 0, LDAP_DEREF_NEVER,
        [['oid' => LDAP_CONTROL_PAGEDRESULTS, 'value' => ['size' => 2, 'cookie' => $cookie]]]
    );
    ldap_parse_result($link, $result, $errcode , $matcheddn , $errmsg , $referrals, $controls);
    // To keep the example short errors are not tested
    $entries = ldap_get_entries($link, $result);
    foreach ($entries as $entry) {
        echo "cn: ".$entry['cn'][0]."\n";
    }
    if (isset($controls[LDAP_CONTROL_PAGEDRESULTS]['value']['cookie'])) {
        // You need to pass the cookie from the last call to the next one
        $cookie = $controls[LDAP_CONTROL_PAGEDRESULTS]['value']['cookie'];
    } else {
        $cookie = '';
    }
    // Empty cookie means last page
} while (strlen($cookie) > 0);
?>