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<?php
# $Id: ldap.php 2459 2017-12-10 22:17:52Z richard $

/* written by steweb57, Rexy & Tom HOUDAYER */
/****************************************************************
*                       GLOBAL FILE PATHS                       *
*****************************************************************/
define('CONF_FILE', '/usr/local/etc/alcasar.conf');

/****************************************************************
*                       FILE reading test                       *
*****************************************************************/
$conf_files = array(CONF_FILE);
foreach ($conf_files as $file) {
        if (!file_exists($file)) {
                exit("Fichier $file non présent");
        }
        if (!is_readable($file)) {
                exit("Vous n'avez pas les droits de lecture sur le fichier $file");
        }
}

/****************************************************************
*                       Read CONF_FILE                          *
*****************************************************************/
$file_conf = fopen(CONF_FILE, 'r');
if (!$file_conf) {
        exit('Error opening the file '.CONF_FILE);
}
while (!feof($file_conf)) {
        $buffer = fgets($file_conf, 4096);
        if ((strpos($buffer, '=') !== false) && (substr($buffer, 0, 1) !== '#')) {
                $tmp = explode('=', $buffer, 2);
                $conf[trim($tmp[0])] = trim($tmp[1]);
        }
}
fclose($file_conf);

/****************************************************************
*                       Choice of language                      *
*****************************************************************/
$Language = 'en';
if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
        $Langue   = explode(',', $_SERVER['HTTP_ACCEPT_LANGUAGE']);
        $Language = strtolower(substr(chop($Langue[0]), 0, 2));
}
if ($Language === 'fr') {               // French
        $l_ldap_update                  = "Mise à jour des paramètres LDAP effectuée";
        $l_ldap_title                   = "Authentification externe : LDAP";
        $l_ldap_legend                  = "Authentification LDAP";
        $l_ldap_auth_enable_label       = "Éditer la configuration LDAP:";
        $l_ldap_YES                     = "OUI";
        $l_ldap_NO                      = "NON";
        $l_ldap_server_label            = "Serveur LDAP:";
        $l_ldap_server_text             = "Adresse IP du serveur";
        $l_ldap_base_dn_label           = "DN de la base:";
        $l_ldap_base_dn_text            = "Le DN (Distinguished Name) définit où se situent les informations des utilisateurs dans l'annuaire.<br> - Exemple LDAP: 'o=mycompany, c=FR'.<br> - Exemple AD 'cn=Users,dc=server_name,dc=localdomain'";
        $l_ldap_uid_label               = "Identifiant d'utilisateur (UID):";
        $l_ldap_uid_text                = "Clé utilisée pour rechercher un identifiant de connexion.<br> - Exemple LDAP: 'uid', 'sn', etc.<br> - Pour A.D. mettre 'sAMAccountName'.";
        $l_ldap_base_filter_label       = "Filtre de recherche des utilisateurs (optionnel):";
        $l_ldap_base_filter_text        = "Vous pouvez limiter les objets recherchés avec des filtres additionnels.<br> Exemple 'objectClass=posixGroup' ajouterait le filtre '(&amp;(uid=username)(objectClass=posixGroup))'";
        $l_ldap_user_label              = "CN de l'utilisateur exploité par ALCASAR:";
        $l_ldap_user_text               = "CN=Common Name. Laissez vide pour utiliser un accès invité (ou anonyme). Obligatoire sur un AD.<br> - Exemple LDAP : 'uid=username,ou=my_lan,o=mycompany,c=FR'.<br> - Exemple AD : 'username' ou 'cn=username,cn=Users,dc=server_name,dc=localdomain'";
        $l_ldap_password_label          = "Mot de passe:";
        $l_ldap_password_text           = "Laissez vide pour un accès invité (ou anonyme). Obligatoire sur un AD.";
        $l_ldap_submit                  = "Enregistrer et vérifier";
        $l_ldap_test_service_failed     = "Service LDAP injoignable sur ce serveur (vérifiez l'@IP).";
        $l_ldap_test_service_ok         = "Un port 389 est actif sur ce serveur";
        $l_ldap_test_connection_failed  = "Connexion LDAP impossible (vérifiez le service LDAP sur ce serveur)";
        $l_ldap_test_connection_ok      = "Une connexion LDAP a été établie";
        $l_ldap_test_bind_failed        = "Echec d'authentification (vérifiez l'utilisateur et le mot de passe)";
        $l_ldap_test_bind_ok            = "L'authentification a réussie";
        $l_ldap_test_dn_failed          = "Le DN de la base semble incorrect (vérifiez le)";
        $l_ldap_test_dn_ok              = "Le DN de la base semble correct";
        $l_ldap_error                   = "erreur LDAP";
        $l_ldap_entries                 = "entrées dans la base";
        $l_ldap_push_config             = "Activer cette configuration";
} else {                                // English
        $l_ldap_update                  = "LDAP settings updated";
        $l_ldap_title                   = "External authentication : LDAP";
        $l_ldap_legend                  = "LDAP authentication";
        $l_ldap_auth_enable_label       = "Edit the LDAP configuration :";
        $l_ldap_YES                     = "YES";
        $l_ldap_NO                      = "NO";
        $l_ldap_server_label            = "LDAP server :";
        $l_ldap_server_text             = "IP address of the LDAP server.";
        $l_ldap_base_dn_label           = "DN of the base:";
        $l_ldap_base_dn_text            = "The DN (Distinguished Name) is used to locate the users information in the directory.<br> e.g. LDAP : 'o=MyCompany,c=US'.<br> e.g. AD : 'cn=Users,dc=server_name,dc=localdomain'";
        $l_ldap_uid_label               = "User IDentifier (UID):";
        $l_ldap_uid_text                = "Key used to search for a given login identity.<br>e.g. 'uid', 'sn', etc.. For AD use 'sAMAccountName'.";
        $l_ldap_base_filter_label       = "User search filter (optional):";
        $l_ldap_base_filter_text        = "You can further limit the searched objects with additional filters.<br> For example 'objectClass=posixGroup' would result in the use of '(&amp;(uid=username)(objectClass=posixGroup))'";
        $l_ldap_user_label              = "CN of the user operated by ALCASAR:";
        $l_ldap_user_text               = "CN=Common Name. Leave blank to use anonymous binding. Mandatory for AD.<br> e.g. LDAP :'uid=Username,ou=my_lan,o=mycompany,c=US'.<br> e.g. AD : 'username' or 'cn=username,cn=Users,dc=server_name,dc=localdomain'";
        $l_ldap_password_label          = "Password:";
        $l_ldap_password_text           = "Leave blank to use anonymous binding. Mandatory for AD.";
        $l_ldap_submit                  = "Save & Check";
        $l_ldap_test_service_failed     = "LDAP service is not reachable on that server (check IP)";
        $l_ldap_test_service_ok         = "A port 389 is open on this server";
        $l_ldap_test_connection_failed  = "LDAP connexion failed (check the LDAP service on this server)";
        $l_ldap_test_connection_ok      = "A LDAP connexion is established";
        $l_ldap_test_bind_failed        = "LDAP authentication failed (check the LDAP user and password)";
        $l_ldap_test_bind_ok            = "Successful authentication";
        $l_ldap_test_dn_failed          = "DN of the base seems to be wrong (check it)";
        $l_ldap_test_dn_ok              = "DN of the base seems to be ok";
        $l_ldap_error                   = "LDAP error";
        $l_ldap_entries                 = "entries in the base";
        $l_ldap_push_config             = "Activate this configuration";
}


function ldap_checkServerConfig($f_ldap_server, $f_ldap_identity, $f_ldap_password, $f_ldap_basedn, $f_ldap_uid, $f_ldap_port = 389) {
        // Socket to the LDAP port of the server
        if (!$sock = @fsockopen($f_ldap_server, $f_ldap_port, $num, $error, 2)) {
                // no network connection
                return -2;
        }
        fclose($sock);

        // if ok, Test LDAP connection
        $ldapconn = ldap_connect($f_ldap_server, $f_ldap_port);
        ldap_set_option($ldapconn, LDAP_OPT_TIMELIMIT, 2);
        if (!$ldapconn) {
                // LDAP connection failed
                return -1;
        }

        // if ok, test a ldap-bind with the user used by ALCASAR
        $ldapbind = ldap_bind($ldapconn, $f_ldap_identity, $f_ldap_password);
        if (!$ldapbind) {
                // Test LDAP Version 3
                ldap_set_option($ldapconn, LDAP_OPT_PROTOCOL_VERSION, 3);
                $ldapbind = ldap_bind($ldapconn, $f_ldap_identity, $f_ldap_password);
                if (!$ldapbind) {
                        // LDAP Bind failed
                        return 0;
                }
        }

        // if ok, try to query the directory of users
        $query = $f_ldap_uid."=*";
        $ldap_result = ldap_search($ldapconn, $f_ldap_basedn, $query);
        if (ldap_search($ldapconn, $f_ldap_basedn, $query)) {
                $ldap_users_number = ldap_count_entries($ldapconn, $ldap_result);
                return $ldap_users_number;
        } else {
                return 1;
        }
        ldap_unbind($ldapconn);
}

$messages = '';
$ldap_can_be_enabled = False;

if (isset($_POST['auth_enable'])) {
        if ($_POST['auth_enable'] === '1') {
                $varErrors = [];
                if (isset($_POST['ldap_server']))      $ldap_server      = $_POST['ldap_server'];      else array_push($varErrors, 'Variable error "ldap_server"');
                if (isset($_POST['ldap_base_dn']))     $ldap_base_dn     = $_POST['ldap_base_dn'];     else array_push($varErrors, 'Variable error "ldap_base_dn"');
                if (isset($_POST['ldap_uid']))      $ldap_uid      = $_POST['ldap_uid'];      else array_push($varErrors, 'Variable error "ldap_uid"');
                if (isset($_POST['ldap_base_filter'])) $ldap_base_filter = $_POST['ldap_base_filter']; else array_push($varErrors, 'Variable error "ldap_base_filter"');
                if (isset($_POST['ldap_user']))        $ldap_user        = $_POST['ldap_user'];        else array_push($varErrors, 'Variable error "ldap_user"');
                if (isset($_POST['ldap_password']))    $ldap_password    = $_POST['ldap_password'];    else array_push($varErrors, 'Variable error "ldap_password"');

                // Validation
                if (isset($ldap_server)) {
                        if ((!preg_match('/^([0-9]{1,3}\.){3}([0-9]{1,3})$/', $ldap_server)) && (preg_match('/^[a-zA-Z0-9-_.]+$/', $ldap_server))) {
                                $ldap_server = gethostbyname($ldap_server);
                        }
                        if (!preg_match('/^([0-9]{1,3}\.){3}([0-9]{1,3})$/', $ldap_server)) {
                                array_push($varErrors, 'Invalid LDAP server IP');
                        }
                }

                if (!empty($varErrors)) { 
                        $messages .= '<div style="text-align: center"><br>';
                        foreach ($varErrors as $error) {
                                $messages .= '<span style="font-weight: bold; color: red;">'.$error.'</span><br>';
                        }
                        $messages .= '<br></div>';
                } else {
                        exec('sed -i \'s/^LDAP=.*/LDAP=on/g\' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_SERVER=.*/LDAP_SERVER=$ldap_server/g").' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_BASE=.*/LDAP_BASE=$ldap_base_dn/g").' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_UID=.*/LDAP_UID=$ldap_uid/g").' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_FILTER=.*/LDAP_FILTER=$ldap_base_filter/g").' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_USER=.*/LDAP_USER=$ldap_user/g").' '.CONF_FILE);
                        exec('sed -i '.escapeshellarg("s/^LDAP_PASSWORD=.*/LDAP_PASSWORD=$ldap_password/g").' '.CONF_FILE);
                        exec('sudo /usr/local/bin/alcasar-ldap.sh --on');

                        $messages .= '<div style="text-align: center"><br>';
                        $messages .= '<span style="font-weight: bold; color: green;">'.$l_ldap_update.'</span><br>';
                        $messages .= '<br></div>';
                }
        } else {
                exec('sed -i "s/^LDAP=.*/LDAP=off/g" '.CONF_FILE);
                exec('sudo /usr/local/bin/alcasar-ldap.sh --off');

                $messages .= '<div style="text-align: center"><br>';
                $messages .= '<span style="font-weight: bold; color: green;">'.$l_ldap_update.'</span><br>';
                $messages .= '<br></div>';
        }

        // Reload configuration
        $file_conf = fopen(CONF_FILE, 'r');
        if (!$file_conf) {
                exit('Error opening the file '.CONF_FILE);
        }
        while (!feof($file_conf)) {
                $buffer = fgets($file_conf, 4096);
                if ((strpos($buffer, '=') !== false) && (substr($buffer, 0, 1) !== '#')) {
                        $tmp = explode('=', $buffer, 2);
                        $conf[trim($tmp[0])] = trim($tmp[1]);
                }
        }
        fclose($file_conf);
}

// LDAP configuration params
$ldap_status      = ($conf['LDAP'] === 'on');
$ldap_server      = $conf['LDAP_SERVER'];
$ldap_user        = $conf['LDAP_USER'];
$ldap_password    = $conf['LDAP_PASSWORD'];
$ldap_base_dn     = $conf['LDAP_BASE'];
$ldap_uid         = $conf['LDAP_UID'];
$ldap_base_filter = $conf['LDAP_FILTER'];

// TODO : check LDAP PHP extension loaded?
// if (!extension_loaded('ldap')) {
//      exit();
// }

$pos = strpos($ldap_server, '//');
if ($pos !== false) {
        // TODO : useless?
        $new_ldap_server = explode('//', $ldap_server); // pour discriminer le host et le protocole dans la notation "ldap://192.168.182.10" ou "ldaps://monldap.monentreperise.com"
} else {
        $new_ldap_server = $ldap_server;
}
if ($ldap_status) {
        $serverCheckResult = ldap_checkServerConfig($new_ldap_server, $ldap_user, $ldap_password, $ldap_base_dn, $ldap_uid);
}

// AJAX LDAP configuration checker
if (isset($_GET['conf_check'])) {
        $response = [
                'enable' => $ldap_status
        ];
        if ($ldap_status || ($_SERVER['REQUEST_METHOD'] === 'POST')) {
                $varErrors = [];
                if ($_SERVER['REQUEST_METHOD'] === 'POST') {
                        if (isset($_POST['ldap_server']))      $ldap_server      = $_POST['ldap_server'];      else array_push($varErrors, 'Variable error "ldap_server"');
                        if (isset($_POST['ldap_base_dn']))     $ldap_base_dn     = $_POST['ldap_base_dn'];     else array_push($varErrors, 'Variable error "ldap_base_dn"');
                        if (isset($_POST['ldap_uid']))      $ldap_uid      = $_POST['ldap_uid'];      else array_push($varErrors, 'Variable error "ldap_uid"');
                        if (isset($_POST['ldap_base_filter'])) $ldap_base_filter = $_POST['ldap_base_filter']; else array_push($varErrors, 'Variable error "ldap_base_filter"');
                        if (isset($_POST['ldap_user']))        $ldap_user        = $_POST['ldap_user'];        else array_push($varErrors, 'Variable error "ldap_user"');
                        if (isset($_POST['ldap_password']))    $ldap_password    = $_POST['ldap_password'];    else array_push($varErrors, 'Variable error "ldap_password"');
                }

                // Validation
                if (isset($ldap_server)) {
                        if ((!preg_match('/^([0-9]{1,3}\.){3}([0-9]{1,3})$/', $ldap_server)) && (preg_match('/^[a-zA-Z0-9-_.]+$/', $ldap_server))) {
                                $ldap_server = gethostbyname($ldap_server);
                        }
                        if (!preg_match('/^([0-9]{1,3}\.){3}([0-9]{1,3})$/', $ldap_server)) {
                                array_push($varErrors, 'Invalid LDAP server IP');
                        }
                }

                $response['result'] = (ldap_checkServerConfig($ldap_server, $ldap_user, $ldap_password, $ldap_base_dn, $ldap_uid) > 0);

                if (!empty($varErrors)) {
                        $response['errors'] = $varErrors;
                }
        }

        header('Content-Type: application/json');
        echo json_encode($response);
        exit();
}

?>
<!DOCTYPE html>
<html>
<head>
        <meta charset="UTF-8">
        <title><?= $l_ldap_title ?></title>
        <link type="text/css" href="/css/style.css" rel="stylesheet">
        <link type="text/css" href="/css/acc.css" rel="stylesheet">
        <link type="text/css" href="/css/ldap.css" rel="stylesheet">
        <script>
        function onLdapStatusChange() {
                var listToDisables = ['ldap_server', 'ldap_dn', 'ldap_uid', 'ldap_base_filter', 'ldap_user', 'ldap_password'];

                if (document.getElementById('auth_enable').value === '1') {
                        for (var i=0; i<listToDisables.length; i++) {
                                document.getElementById(listToDisables[i]).style.backgroundColor = '#ffffff';
                                document.getElementById(listToDisables[i]).disabled = false;
                        }
                } else {
                        for (var i=0; i<listToDisables.length; i++) {
                                document.getElementById(listToDisables[i]).style.backgroundColor = '#c0c0c0';
                                document.getElementById(listToDisables[i]).disabled = true;
                        }
                }
        }

        function checkConfig() {
                var ldap_config = {
                        ldap_status:     (document.getElementById('auth_enable').value === '1'),
                        ldap_server:      document.getElementById('ldap_server').value,
                        ldap_user:        document.getElementById('ldap_user').value,
                        ldap_password:    document.getElementById('ldap_password').value,
                        ldap_base_dn:     document.getElementById('ldap_dn').value,
                        ldap_uid:      document.getElementById('ldap_uid').value,
                        ldap_base_filter: document.getElementById('ldap_base_filter').value
                };

                console.log(ldap_config);

                var params = Object.keys(ldap_config).map( function (k) { return encodeURIComponent(k) + '=' + encodeURIComponent(ldap_config[k]) } ).join('&');

                var xhr = new XMLHttpRequest();
                xhr.onreadystatechange = function() {
                        if (this.readyState == 4) {
                                if (this.status == 200) {
                                        var data = JSON.parse(this.responseText);

                                        if (data.result === true) {
                                                alert('Configuration valide');
                                        } else {
                                                alert('Configuration non valide');
                                        }

                                        if (typeof data.errors !== 'undefined') {
                                                alert(data.errors.join("\n"));
                                        }

                                        console.log(data)
                                } else {
                                        console.log(this.responseText)
                                }
                        }
                };
                xhr.open('POST', 'ldap.php?conf_check', true);
                xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
                xhr.send(params);
        }
        </script>
</head>
<body onLoad="onLdapStatusChange();">
        <div class="panel">
                <div class="panel-header"><?= $l_ldap_legend ?></div>
                <div class="panel-body">
                        <form name="config_ldap" method="POST" action="<?= htmlspecialchars($_SERVER['PHP_SELF']) ?>">
                                <fieldset>
                                        <legend>
                                                <?= $messages ?>
                                                <?php if ($ldap_status): ?>
                                                        <div style="text-align: center"><br>
                                                                <?php if ($serverCheckResult === -2): ?>
                                                                        <span style="color: red"><?= $l_ldap_test_service_failed ?></span>
                                                                <?php elseif ($serverCheckResult === -1): ?>
                                                                        <span style="color: green"><?= $l_ldap_test_service_ok ?></span><br>
                                                                        <span style="color: red"><?= $l_ldap_test_connection_failed ?></span>
                                                                <?php elseif ($serverCheckResult === 0): ?>
                                                                        <span style="color: green"><?= $l_ldap_test_service_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_connection_ok ?></span><br>
                                                                        <span style="color: red"><?= $l_ldap_test_bind_failed ?></span>
                                                                <?php elseif ($serverCheckResult === 1): ?>
                                                                        <span style="color: green"><?= $l_ldap_test_service_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_connection_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_bind_ok ?></span><br>
                                                                        <span style="color: red"><?= $l_ldap_test_dn_failed ?></span>
                                                                <?php elseif ($serverCheckResult > 1): ?>
                                                                        <span style="color: green"><?= $l_ldap_test_service_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_connection_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_bind_ok ?></span><br>
                                                                        <span style="color: green"><?= $l_ldap_test_dn_ok." ($serverCheckResult $l_ldap_entries)"; $ldap_can_be_enabled = True;?></span>
                                                                <?php else: ?>
                                                                        <span><?= $l_ldap_error ?></span>
                                                                <?php endif ?>
                                                                <br><br>
                                                        </div>
                                                <?php endif ?>
                                        </legend>
                                        <dl>
                                                <dt>
                                                        <label for="auth_enable"><?= $l_ldap_auth_enable_label ?></label>
                                                </dt>
                                                <dd>
                                                        <select id="auth_enable" name="auth_enable" onchange="onLdapStatusChange();">
                                                                <option value="1"<?= ($ldap_status)  ? ' selected="selected"' : '' ?>><?= $l_ldap_YES ?></option>
                                                                <option value="0"<?= (!$ldap_status) ? ' selected="selected"' : '' ?>><?= $l_ldap_NO ?></option>
                                                        </select>
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_server"><?= $l_ldap_server_label ?></label><br>
                                                        <?= $l_ldap_server_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_server" size="40" name="ldap_server" value="<?= htmlspecialchars($ldap_server) ?>">
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_dn"><?= $l_ldap_base_dn_label ?></label><br>
                                                        <?= $l_ldap_base_dn_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_dn" size="40" name="ldap_base_dn" value="<?= htmlspecialchars($ldap_base_dn) ?>">
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_uid"><?= $l_ldap_uid_label ?></label><br>
                                                        <?= $l_ldap_uid_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_uid" size="40" name="ldap_uid" value="<?= htmlspecialchars($ldap_uid) ?>">
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_base_filter"><?= $l_ldap_base_filter_label ?></label><br>
                                                        <?= $l_ldap_base_filter_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_base_filter" size="40" name="ldap_base_filter" value="<?= htmlspecialchars($ldap_base_filter) ?>">
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_user"><?= $l_ldap_user_label ?></label><br>
                                                        <?= $l_ldap_user_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_user" size="40" name="ldap_user" value="<?= htmlspecialchars($ldap_user) ?>">
                                                </dd>
                                        </dl>
                                        <dl>
                                                <dt>
                                                        <label for="ldap_password"><?= $l_ldap_password_label ?></label><br>
                                                        <?= $l_ldap_password_text ?>
                                                </dt>
                                                <dd>
                                                        <input id="ldap_password" type="password" size="40" name="ldap_password" value="<?= htmlspecialchars($ldap_password) ?>">
                                                </dd>
                                        </dl>
                                        <p>
                                                <input id="submit" type="submit" value="<?= $l_ldap_submit ?>" name="submit">
                                                <? if ($ldap_can_be_enabled === True) {echo "<input id=\"push_config\" value=\"$l_ldap_push_config\" name=\"push_config_button\">";}?>
                                        </p>
                                </fieldset>
                        </form>
                </div>
        </div>
</body>
</html>