<?php
// Pandora FMS - the Flexible Monitoring System
// ============================================
// Copyright (c) 2009 Evi Vanoost, vanooste@rcbi.rochester.edu
// Please see http://pandora.sourceforge.net for full contribution list

// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation for version 2.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
// Database configuration (default ones)
	
if (!isset ($config)) {
	die ('You cannot access this file directly!');
}

$config["user_can_update_info"] = false;
$config["user_can_update_password"] = false;
$config["admin_can_add_user"] = false;
$config["admin_can_delete_user"] = false;
$config["admin_can_disable_user"] = false; //Not implemented
$config["admin_can_make_admin"] = false;

//Required and optional keys for this function to work
$req_keys = array ("ldap_server", "ldap_base_dn", "ldap_login_attr", "ldap_admin_group_name", "ldap_admin_group_attr", "ldap_admin_group_type", "ldap_user_filter", "ldap_user_attr");
$opt_keys = array ("ldap_port", "ldap_start_tls", "ldap_version", "ldap_admin_dn", "ldap_admin_pwd");

global $ldap_cache; //Needs to be globalized because process_config () function calls this file first and the variable would be local and subsequently lost
$ldap_cache = array ();
$ldap_cache["error"] = "";
$ldap_cache["ds"] = "";

//Put each required key in a variable.
foreach ($req_keys as $key) {
	if (!isset ($config["auth"][$key])) {
		user_error ("Required key ".$key." not set", E_USER_ERROR);
	}
}

// Convert group name to lower case to prevent problems
$config["auth"]["ldap_admin_group_attr"] = strtolower ($config["auth"]["ldap_admin_group_attr"]);
$config["auth"]["ldap_admin_group_type"] = strtolower ($config["auth"]["ldap_admin_group_type"]);

foreach ($opt_keys as $key) {
	if (!isset ($config["auth"][$key])) {
		switch ($key) {
			case "ldap_start_tls":
				$config["auth"][$key] = false;
				continue;
			case "ldap_version":
				$config["auth"][$key] = 0;
				continue;
			case "ldap_admin_dn":
			case "ldap_admin_pwd":	
				$config["auth"][$key] = "";
				continue;
			default:
				//Key not implemented
				continue;
		}
	}
}

//Reference the global use authorization error to last ldap error.
$config["auth_error"] = &$ldap_cache["error"];

unset ($req_keys, $opt_keys);
	

/**
 * process_user_login accepts $login and $pass and handles it according to current authentication scheme
 *
 * @param string $login 
 * @param string $pass
 *
 * @return mixed False in case of error or invalid credentials, the username in case it's correct.
 */
function process_user_login ($login, $pass) {
	if (!ldap_valid_login ($login, $pass)) {
		return false;
	} 
	global $config;
		
	$profile = get_db_value ("id_usuario", "tusuario_perfil", "id_usuario", $login);
	
	if ($profile === false && empty ($config["auth"]["create_user_undefined"])) {
		$config["auth_error"] = "No profile"; //Error message, don't translate
		return false; //User doesn't have a profile so doesn't have access
	} elseif ($profile === false && !empty ($config["auth"]["create_user_undefined"])) {
		$ret = create_user_profile ($login); //User doesn't have a profile but we are asked to create one
		if ($ret === false) {
			$config["auth_error"] = "Profile creation failed"; //Error message, don't translate
			return false; //We couldn't create the profile for some or another reason
		}
	}
	
	return $login;
}

/** 
 * Checks if a user is administrator.
 * 
 * @param string User id.
 * 
 * @return bool True is the user is admin
 */
function is_user_admin ($user_id) {
	$admins = get_user_admins ();
	
	if (in_array ($user_id, $admins)) {
		return true;
	}
	
	return false;
}

/**
 * Checks if a user exists
 *
 * @param string User id.
 *
 * @return bool True if the user exists
 */
function is_user ($id_user) {
	$user = get_user_info ($id_user);
	if (empty ($user))
		return false;
	return true;
}

/** 
 * Gets the users real name
 * 
 * @param string User id.
 * 
 * @return string The users full name
 */
function get_user_fullname ($id_user) {
	$info = get_user_info ($id_user);
	if (empty ($info)) {
		//User doesn't exist
		return '';
	}
	return (string) $info["fullname"];
}

/** 
 * Gets the users email
 * 
 * @param string User id.
 * 
 * @return string The users email address
 */
function get_user_email ($id_user) {
	$info = get_user_info ($id_user);
	return (string) $info["email"];
}

/** 
 * Get the user id field on a mixed structure.
 *
 * This function is needed to make auth system more compatible and independant.
 *
 * @param mixed User structure to get id. It might be a row returned from
 * tusuario or tusuario_perfil. If it's not a row, the int value is returned.
 */
function get_user_id ($user) {
	if (is_array ($user))
		/* FIXME: Is this right? */
		return $user['id_user'];
	return (int) $user;
}

/** 
 * Gets the users info
 * 
 * @param string User id.
 * 
 * @return array User info
 */
function get_user_info ($id_user) {
	global $ldap_cache;
	
	if (!empty ($ldap_cache[$id_user])) {
		return $ldap_cache[$id_user];
	}
	
	$ldap_cache[$id_user] = ldap_load_user ($id_user);
	
	if ($ldap_cache[$id_user] === false) {
		return array ();
	}
	
	return $ldap_cache[$id_user];
}
	
/**
 * Get all users that are defined in the admin group in LDAP
 *
 * @return array Array of users or empty array
 */
function get_user_admins () {
	global $ldap_cache, $config;
	
	if (! empty ($ldap_cache["cached_admins"])) {
		return $ldap_cache["cached_admins"];
	} else {
		$ldap_cache["cached_admins"] = array ();
	}
	
	if (ldap_connect_bind ()) {
		$search_filter = "(".$config["auth"]["ldap_admin_group_attr"]."=*)";
		$sr = ldap_search ( $ldap_cache["ds"], $config["auth"]["ldap_admin_group_name"], $search_filter, array ($config["auth"]["ldap_admin_group_attr"]));
		if (!$sr) {
			$ldap_cache["error"] .= 'Error searching LDAP server (get_user_admins): ' . ldap_error ($ldap_cache["ds"]);
		} else {
			$admins = ldap_get_entries( $ldap_cache["ds"], $sr);
			for( $x = 0; $x < $admins[0][$config["auth"]["ldap_admin_group_attr"]]['count']; $x++) {
				if ($config["auth"]["ldap_admin_group_type"] != 'posixgroup') {
					$ldap_cache["cached_admins"][] = stripdn ($admins[0][$config["auth"]["ldap_admin_group_attr"]][$x]);
				} else {
					$ldap_cache["cached_admins"][] = $admins[0][$config["auth"]["ldap_admin_group_attr"]][$x];
				}
			}
			@ldap_free_result($sr);
		}
		@ldap_close ($ldap_cache["ds"]);
	}
	
	return $ldap_cache["cached_admins"];
}

/**
 * Sets the last login for a user. LDAP doesn't have this (or it's inherent to the login process)
 *
 * @param string User id
 */
function process_user_contact ($id_user) {
	//Empty function
}

/**
 * LDAP user functions based on webcalendar's implementation
 *
 * File from webcalendar (GPL) project:
 * $Id: user-ldap.php,v 1.42.2.1 2007/08/17 14:39:00 umcesrjones Exp $
 *
 * Note: this application assumes that usernames (logins) are unique.
 */

/**
 * Function to search the dn for a given user. Error messages in $ldap_cache["error"];
 *
 * @param string User login
 *
 * @return mixed The DN if the user is found, false in other case
 */
function ldap_search_user ($login) {
	global $ldap_cache, $config;
	
	$nick = false;
	if (ldap_connect_bind ()) {
		$sr = @ldap_search ($ldap_cache["ds"], $config["auth"]["ldap_base_dn"], "(&(".$config["auth"]["ldap_login_attr"]."=".$login.")".$config["auth"]["ldap_user_filter"].")", array_values ($config["auth"]["ldap_user_attr"]));
		
		if (!$sr) {
			$ldap_cache["error"] .= 'Error searching LDAP server: ' . ldap_error ($ldap_cache["ds"]);
		} else {
			$info = @ldap_get_entries ($ldap_cache["ds"], $sr );
			if ( $info['count'] != 1 ) {
				$ldap_cache["error"] .= 'Invalid user';
			} else {
				$nick = $info[0]['dn'];
			}
			@ldap_free_result ($sr);
		}
		@ldap_close ($ldap_cache["ds"]);
	}
	return $nick;
}

/**
 * Function to validate the user and password for a given login. Error messages in $ldap_cache["error"];
 *
 * @param string User login
 * @param string User password (plain text)
 *
 * @return bool True if the login is correct, false in other case
 */
function ldap_valid_login ($login, $password) {
	global $ldap_cache, $config;
	
	if (! function_exists ("ldap_connect")) {
		die ("Your installation of PHP does not support LDAP");
	}
	
	$ret = false;
	if (!empty ($config["auth"]["ldap_port"])) {
		$ds = @ldap_connect ($config["auth"]["ldap_server"], $config["auth"]["ldap_port"]); //Since this is a separate bind, we don't store it global
	} else {
		$ds = @ldap_connect ($config["auth"]["ldap_server"]); //Since this is a separate bind we don't store it global
	}
	if ($ds) {
		if ($config["auth"]["ldap_version"] > 0) {
			ldap_set_option ($ds, LDAP_OPT_PROTOCOL_VERSION, $config["auth"]["ldap_version"]);
		}
		
		if ($config["auth"]["ldap_start_tls"] && !@ldap_start_tls ($ds)) {
			$ldap_cache["error"] .= 'Could not start TLS for LDAP connection';
			return $ret;
		}
		
		if (ldap_search_user ($login)) {
			$r = @ldap_bind ($ds, $config["auth"]["ldap_login_attr"]."=".$login.",".$config["auth"]["ldap_base_dn"], $password);
			if (!$r) {
				$ldap_cache["error"] .= 'Invalid login';
				//$ldap_cache["error"] .= ': incorrect password'; // uncomment for debugging
			} else {
				$ret = true;
			}
		} else {
			$ldap_cache["error"] .= 'Invalid login';
			//$ldap_cache["error"] .= ': no such user';
		}
		@ldap_close ($ds);
	} else {
		$ldap_cache["error"] .= 'Error connecting to LDAP server';
	}
	return $ret;
}

/**
 * Function to load user information according to PandoraFMS structure. Error messages in $ldap_cache["error"];
 *
 * @param string User login
 *
 * @return mixed Array with the information, false in other case
 */
function ldap_load_user ($login) {
	global $ldap_cache, $config;
		
	$ret =  false;
	$time = get_system_time ();
	if (ldap_connect_bind ()) {
		
		$sr = ldap_search ($ldap_cache["ds"], $config["auth"]["ldap_base_dn"], "(&(".$config["auth"]["ldap_login_attr"]."=".$login.")".$config["auth"]["ldap_user_filter"].")", array_values ($config["auth"]["ldap_user_attr"]));
		
		if (!$sr) {
			$ldap_cache["error"] .= 'Error searching LDAP server (load_user): ' . ldap_error( $ldap_cache["ds"] );
		} else {
			$info = @ldap_get_entries ($ldap_cache["ds"], $sr);
			if ($info['count'] != 1) {
				$ldap_cache["error"] .= 'Invalid login';
				//$ldap_cache["error"] .= ', could not load user'; //Uncomment for debugging
			} else {
				$ret = array ();
				foreach ($config["auth"]["ldap_user_attr"] as $internal_key => $ldap_key) {
					$ret["last_connect"] = $time;
					$ret["registered"] = $time;
					$ret["is_admin"] = is_user_admin ($info[0][$config["auth"]["ldap_user_attr"]["id_user"]][0]);
					if (isset ($info[0][$ldap_key])) {
						$ret[$internal_key] = $info[0][$ldap_key][0];
					} else {
						$ret[$internal_key] = '';
					}
				}
			}
			@ldap_free_result ($sr);
		}
		@ldap_close ( $ldap_cache["ds"] );
	} else {
		$ldap_cache["error"] .= 'Could not connect to LDAP server';
	}

	return $ret;
}

/**
 * Function to create a new user. We don't do LDAP admin in Pandora, so not implemented.
 *
 * @return bool false
 */
function create_user () {
	global $ldap_cache;
	
	$ldap_cache["error"] .= 'Creating users not supported.';
	return false;
}

/**
 * Function to update a user. We don't do LDAP admin in Pandora, so not implemented.
 *
 * @return bool false
 */
function process_user () {
	global $ldap_cache;
	
	$ldap_cache["error"] .= 'Updating users not supported.';
	return false;
}

/**
 * Function to update a user password. We don't do LDAP admin in Pandora, so not implemented.
 *
 * @return bool false
 */
function update_user_password ($user, $password_old, $password_new) {
	global $ldap_cache;
	
	$ldap_cache["error"] = 'Changing passwords not supported';
	return false;
}

/**
 * Delete a user (preferences etc.) from the pandora database (NOT from LDAP)
 *
 * @param string $user User to delete
 *
 * @return bool True if successfully deleted, false otherwise
 */
function delete_user ($user) {
	global $ldap_cache;
	
	$ldap_cache["error"] = 'Deleting users not supported';
	return false;
}

/**
 * Function to get all users (for LDAP this also includes the admin users which you have to get separate)
 *
 * @param string Order currently not done for LDAP
 *
 * @return array List if successful, empty array otherwise
 */
function get_users ($order = false) {
	global $ldap_cache, $config;
	
	if (!empty ($ldap_cache["cached_users"])) {
		return $ldap_cache["cached_users"];
	}
	
	$ldap_cache["cached_users"] = array ();
	$time = get_system_time ();
	
	if (ldap_connect_bind ()) {
		$sr = @ldap_search ($ldap_cache["ds"], $config["auth"]["ldap_base_dn"], $config["auth"]["ldap_user_filter"], array_values ($config["auth"]["ldap_user_attr"]));
		if (!$sr) {
			$ldap_cache["error"] .= 'Error searching LDAP server (get_users): ' . ldap_error( $ldap_cache["ds"] );
		} else {
			ldap_sort ($ldap_cache["ds"], $sr, $config["auth"]["ldap_user_attr"]["fullname"]);
			$info = @ldap_get_entries( $ldap_cache["ds"], $sr );
			for ( $i = 0; $i < $info['count']; $i++ ) {
				foreach ($config["auth"]["ldap_user_attr"] as $internal_key => $ldap_key) {
					$ret[$info[$i][$config["auth"]["ldap_user_attr"]["id_user"]][0]]["last_connect"] = $time;
					if (isset ($info[$i][$ldap_key])) {
						$ret[$info[$i][$config["auth"]["ldap_user_attr"]["id_user"]][0]][$internal_key] = $info[$i][$ldap_key][0];
					} else {
						$ret[$info[$i][$config["auth"]["ldap_user_attr"]["id_user"]][0]][$internal_key] = '';
					}
					$ret[$info[$i][$config["auth"]["ldap_user_attr"]["id_user"]][0]]["is_admin"] = is_user_admin ($info[$i][$config["auth"]["ldap_user_attr"]["id_user"]][0]);
				}
			}
			@ldap_free_result($sr);
		}
		@ldap_close ( $ldap_cache["ds"] );
	}
	
	//Admins are also users and since they can be in separate channels in LDAP, we merge them
	$ldap_cache["cached_users"] = $ret;
	
	return $ldap_cache["cached_users"];
}

// Strip everything but the username (uid) from a dn.
//  params:
//    $dn - the dn you want to strip the uid from.
//  returns: string - userid
//
//  ex: stripdn(uid=jeffh,ou=people,dc=example,dc=com) returns jeffh
function stripdn ($dn) {
	list ($uid, $trash) = split (',', $dn, 2);
	list ($trash, $user) = split ('=', $uid);
	return ($user);
}

// Connects and binds to the LDAP server
// Tries to connect as $config["auth"]["ldap_admin_dn"] if we set it.
//  returns: bind result or false
function ldap_connect_bind () {
	global $ldap_cache, $config;
	
	if (! function_exists ('ldap_connect')) {
		die ('Your installation of PHP does not support LDAP');
	}
	
	$ret = false;
	
	if (!empty ($config["auth"]["ldap_port"]) && !is_resource ($ldap_cache["ds"])) {
		$ldap_cache["ds"] = @ldap_connect ($config["auth"]["ldap_server"], $config["auth"]["ldap_port"]);
	} elseif (!is_resource ($ldap_cache["ds"])) {
		$ldap_cache["ds"] = @ldap_connect ($config["auth"]["ldap_server"]);
	} else {
		return true;
	}
	
	if ($ldap_cache["ds"]) {
		if (!empty ($config["auth"]["ldap_version"])) {
			ldap_set_option($ldap_cache["ds"], LDAP_OPT_PROTOCOL_VERSION, $config["auth"]["ldap_version"]);
		}
		
		if (!empty ($config["auth"]["ldap_start_tls"])) {
			if (!ldap_start_tls ($ldap_cache["ds"])) {
				$ldap_cache["error"] .= 'Could not start TLS for LDAP connection';
				return $ret;
			}
		}
		
		if (!empty ($config["auth"]["ldap_admin_dn"])) {
			$r = @ldap_bind ($ldap_cache["ds"], $config["auth"]["ldap_admin_dn"], $config["auth"]["ldap_admin_pwd"]);
		} else {
			$r = @ldap_bind ($ldap_cache["ds"]);
		}
		
		if (!$r) {
			$ldap_cache["error"] .= 'Invalid bind login for LDAP Server or (in case of OpenLDAP 2.x) could not connect';
			return $ret;
		}
		return true;
	} else {
		$ldap_cache["error"] .= 'Error connecting to LDAP server';
		return $ret;
	}
}

?>