Features
<?php
/*
* qq: 290359552
* return string : "error" or array("user","pass");
*/
function auth()
{
if (!isset($_SERVER['PHP_AUTH_USER'])) {
header('WWW-Authenticate: Basic realm="My Realm"');
header('HTTP/1.0 401 Unauthorized');
return "error";
} else {
return array( $_SERVER['PHP_AUTH_USER'] , $_SERVER['PHP_AUTH_PW'] );
}
}
// test:
$au= auth();
print_r( $au );
?>
HTTP-Authentifizierung mit PHP
Die HTTP-Authentifizierung durch PHP ist nur verfügbar, wenn PHP als Apache-Modul läuft und funktioniert daher nicht mit der CGI-Version. In einem PHP-Skript für ein Apache-Modul kann man die Funktion header() benutzen, um die Nachricht "Authentifizierung notwendig" an den Client-Browser zu senden, damit dieser ein Fenster zur Eingabe von Benutzername/Passwort öffnet. Hat der Benutzer diese eingegeben, wird die URL des PHP-Scripts mit den vordefinierten Variablen PHP_AUTH_USER, PHP_AUTH_PW und AUTH_TYPE, die den Benutzernamen, das Passwort und den Typ der Authentifizierung enthalten, erneut aufgerufen. Diese vordefinierten Variablen befinden sich in den Arrays $_SERVER und $HTTP_SERVER_VARS. Es werden sowohl die "Basic"- als auch (seit PHP 5.1.0) die "Digest"-Authentifizierungsmethode unterstützt. Näheres hierzu bei der header() Funktion.
Hinweis: Anmerkung zur PHP Version
Superglobale, wie $_SERVER, sind seit PHP » 4.1.0 verfügbar.
Ein Auszug aus einem Skript, das die Clientauthentifizierung auf einer Seite erzwingt, würde so aussehen:
Beispiel #1 Beispiel: Basic-HTTP-Authentifizierung
<?php
if (!isset($_SERVER['PHP_AUTH_USER'])) {
header('WWW-Authenticate: Basic realm="My Realm"');
header('HTTP/1.0 401 Unauthorized');
echo 'Text, der gesendet wird, falls der Benutzer auf Abbrechen drückt';
exit;
} else {
echo "<p>Hallo {$_SERVER['PHP_AUTH_USER']}.</p>";
echo "<p>Sie gaben {$_SERVER['PHP_AUTH_PW']} als Passwort ein.</p>";
}
?>
Beispiel #2 Beispiel: Digest-HTTP-Authentifizierung
In diesem Beispiel wird gezeigt, wie ein einfaches Skript für die Digest-HTTP-Authentifizierung implementiert wird. Weitere Informationen dazu finden Sie im » RFC 2617.
<?php
$realm = 'Geschützter Bereich';
// Benutzer => Passwort
$benutzer = array('admin' => 'mypass', 'gast' => 'gast');
if (empty($_SERVER['PHP_AUTH_DIGEST'])) {
header('HTTP/1.1 401 Unauthorized');
header('WWW-Authenticate: Digest realm="' . $realm .
'",qop="auth",nonce="' . uniqid() . '",opaque="' . md5($realm) .
'"');
die('Text, der gesendet wird, falls der Benutzer auf Abbrechen drückt');
}
// Analysieren der Variable PHP_AUTH_DIGEST
if (!($daten = http_digest_parse($_SERVER['PHP_AUTH_DIGEST'])) ||
!isset($benutzer[$daten['username']]))
die('Falsche Zugangsdaten!');
// Erzeugen einer gültigen Antwort
$A1 = md5($daten['username'] . ':' . $realm . ':' .
$benutzer[$daten['username']]);
$A2 = md5($_SERVER['REQUEST_METHOD'] . ':' . $daten['uri']);
$gueltige_antwort = md5($A1 . ':' . $daten['nonce'] . ':' . $daten['nc'] .
':' . $daten['cnonce'] . ':' . $daten['qop'] . ':' .
$A2);
if ($daten['response'] != $gueltige_antwort)
die('Falsche Zugangsdaten!');
// OK, gültige Benutzername & Passwort
echo 'Sie sind angemeldet als: ' . $daten['username'];
// Funktion zum analysieren der HTTP-Auth-Header
function http_digest_parse($txt) {
// gegen fehlende Daten schützen
$noetige_teile = array('nonce'=>1, 'nc'=>1, 'cnonce'=>1, 'qop'=>1,
'username'=>1, 'uri'=>1, 'response'=>1);
$daten = array();
preg_match_all('@(\w+)=(?:([\'"])([^\2]+)\2|([^\s,]+))@', $txt, $treffer,
PREG_SET_ORDER);
foreach ($treffer as $t) {
$daten[$t[1]] = $t[3] ? $t[3] : $t[4];
unset($noetige_teile[$t[1]]);
}
return $noetige_teile ? false : $daten;
}
?>
Hinweis: Hinweis zur Kompatibilität
Achten Sie für die maximale Kompatibilität mit allen Clients bei den Header-Zeilen auf die richtige Schreibweise! Das Schlüsselwort "Basic" sollte genau so geschrieben werden, der Realm-String muss in doppelte (nicht einfache) Anführungszeichen gesetzt werden und in der HTTP/1.0 401-Zeile darf nur genau ein Leerzeichen vor dem 401-Code stehen. Wie im Beispiel oben zu sehen, müssen die Authentifizierungsparameter durch Kommata getrennt werden.
Anstatt PHP_AUTH_USER und PHP_AUTH_PW wie im Beispiel oben einfach nur auszugeben, werden Sie den Benutzernamen und das Passwort auf Gültigkeit überprüfen wollen. Dies kann durch abfragen einer Datenbank oder die Suche des Benutzers in einer Textdatei geschehen.
Vorsicht bei einigen Internet Explorer-Versionen - sie scheinen sehr wählerisch zu sein, was die Reihenfolge der Header angeht. Abhilfe schafft hier das Senden des WWW-Authenticate-Headers vor dem HTTP/1.0 401-Header.
Um zu unterbinden, dass ein Skript das Passwort einer durch einen traditionellen externen Mechanismus geschützten Seite ausliest, werden die PHP_AUTH Variablen ab PHP 4.3.0 nicht gesetzt, wenn eine externe Authentifizierung für diese bestimmte Seite und Safe Mode aktiviert sind. In diesem Fall kann die Variable REMOTE_USER benutzt werden, um den Benutzer durch die externe Zugriffskontrolle zu identifizieren. Es kann also $_SERVER['REMOTE_USER'] benutzt werden.
Hinweis: Konfigurationshinweis
PHP prüft das Vorhandensein einer AuthType Apache-Direktive, um zu entscheiden, ob eine externe Authentifizierung aktiv ist.
Zu beachten ist, dass obenstehendes keinesfalls jemanden, der auf dem selben Server die Kontrolle über eine nicht authentifizierte URL hat, davon abhalten kann, Passwörter von authentifizierten URLs auszulesen.
Sowohl Netscape als auch der Internet Explorer löschen den lokalen Authentifizierungscache des Browserfensters, wenn der Server eine 401-Meldung zurückgibt. Dies kann benutzt werden, um einen Benutzer "auszuloggen" und eine erneute Eingabe des Benutzernamens/Passworts zu erzwingen. Manchmal wird dieses Verhalten für das automatische Ausloggen nach Ablauf einer bestimmten Zeitspanne oder für einen Logout-Button genutzt.
Beispiel #3 HTTP-Authentifizierung, mit erneuter Anforderung von Name/Passwort
<?php
function authentifizieren() {
header('WWW-Authenticate: Basic realm="Test Authentication System"');
header('HTTP/1.0 401 Unauthorized');
echo "Bitte geben Sie eine gültige Login-ID und das Passwort für den
Zugang ein\n";
exit;
}
if (!isset($_SERVER['PHP_AUTH_USER']) ||
($_POST['Gesehen'] == 1 &&
$_POST['AlteAuth'] == $_SERVER['PHP_AUTH_USER'])) {
authentifizieren();
} else {
echo "<p>Willkommen: {$_SERVER['PHP_AUTH_USER']}<br />";
echo "Alt: {$_REQUEST['AlteAuth']}";
echo "<form action='{$_SERVER['PHP_SELF']}' METHOD='post'>\n";
echo "<input type='hidden' name='Gesehen' value='1' />\n";
echo "<input type='hidden' name='AlteAuth'
value='{$_SERVER['PHP_AUTH_USER']}' />\n";
echo "<input type='submit' value='Erneut Anmelden' />\n";
echo "</form></p>\n";
}
?>
Dieses Verhalten wird vom Authentifizierungsstandard HTTP Basic nicht gefordert, daher sollte man sich nie darauf verlassen. Tests mit Lynx haben gezeigt, dass Lynx die Authentifizierungsinformationen bei Erhalt einer 401-Meldung nicht löscht. Solange der benötigte Berechtigungsnachweis nicht geändert wird, kann der Benutzer auf die vorhergehende Seite zurück und danach vorwärts und die angeforderte Adresse wieder öffnen. Der Benutzer kann die Authentifizierungsinformationen aber durch Drücken von '_' löschen.
Weiterhin muss beachtet werden, dass die HTTP-Authentifizierung vor PHP 4.3.3 unter dem Microsoft IIS mit der CGI-Version von PHP aufgrund einer Einschränkung des IIS nicht funktioniert. Damit sie mit PHP 4.3.3+ funktioniert, müssen Sie die "Directory Security" Ihrer IIS-Konfiguration ändern. Klicken Sie auf "Edit" und aktivieren Sie nur "Anonymous Access". Alle anderen Felder sollten deaktiviert bleiben.
Eine andere Einschränkung gibt es, falls Sie das IIS-Modul (ISAPI) und PHP 4 verwenden: Sie können nicht die PHP_AUTH_*-Variablen benutzen, aber stattdessen steht die Variable HTTP_AUTHORIZATION zur Verfügung. Schauen Sie sich dazu z.B. folgenden Code an: list($user, $pw) = explode(':', base64_decode(substr($_SERVER['HTTP_AUTHORIZATION'], 6)));
Hinweis: IIS-Anmerkung:
Damit die HTTP-Authentifizierung mit dem IIS funktioniert, muss die PHP-Konfigurationsanweisung cgi.rfc2616_headers auf 0 (die Voreinstellung) gesetzt sein.
Hinweis: Falls safe mode aktiviert ist, wird die uid des Skripts dem realm-Teil des WWW-Authenticate-Headers hinzugefügt.
add a note
User Contributed NotesHTTP-Authentifizierung mit PHP
yaqy at qq dot com
21-Jul-2008 01:38
21-Jul-2008 01:38
silkensedai at online dot fr
16-Apr-2008 12:21
16-Apr-2008 12:21
Here is my code for basic authentification login/logout.
Include that code before any of your files:
<?php
function redirect_back($http=true, $html=true, $back=NULL){
if(is_null($back)){
if(isset($_REQUEST['referer'])){
$back = $_REQUEST['referer'];
//}elseif(isset($_SERVER['HTTP_REFERER'])){
// $back = isset($_SERVER['HTTP_REFERER']);
}else{
$back = "index.html";
}
}
if($http) header("Location: $back");
if($html){
$back = htmlspecialchars($back);
print <<<EOF
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="refresh" content="0; url=$back">
</head>
<body>
<h1>HTTP/1.0 401 Unauthorized</h1>
<p><a href="$back">Go back</a></p>
</body>
</html>
EOF;
exit();
}
}
$userid = 0;
$username = false;
if(isset($_SERVER['PHP_AUTH_USER']) and $_SERVER['PHP_AUTH_USER']){
$username = $_SERVER['PHP_AUTH_USER'];
$userid = authenticate($username, $_SERVER['PHP_AUTH_PW']);
if($userid===false) $username=false; // login failed
}
// If login succeeded (we have a username) or logout succeeded (no username)
if(isset($_GET['login']) && $username || isset($_GET['logout']) && !$username){
// Go back
redirect_back();
}elseif(isset($_GET['login']) || isset($_GET['logout'])){
// Ask for password
header('WWW-Authenticate: Basic realm=""');
header('HTTP/1.0 401 Unauthorized');
redirect_back(false);
}
?>
You have to test of $username is not false if you want to be sure the user is authenticated.
Example of use in HTML code:
<?php if($username){ ?>
<p>You are logged in with username <?php print htmlspecialchars($username); ?>.</p>
<ul>
<li><a href="?logout&referer=<?php print htmlspecialchars(urlencode($_SERVER['PHP_SELF'])); ?>">logout</a></li>
</ul>
<?php }else{ ?>
<p>You are anonymous.</p>
<ul>
<li><a href="?login&referer=<?php print htmlspecialchars(urlencode($_SERVER['PHP_SELF'])); ?>">login</a></li>
</ul>
<?php } ?>
AlexTM - alextm84 at gmail dot com
12-Mar-2008 08:04
12-Mar-2008 08:04
/* Bug fix of my previous note: a dot was missing */
I have written this code to use the Digest
authentication with PHP on both APACHE
and IIS_ISAPI.
This code fixes the differences between
the two modules.
I hope this will help.
AlexTM - Alessandro Cosci
<?php
session_start();
$realm = 'My Realm';
$logged = false;
//user => password
$users = array('user1' => 'psw1', 'user2' => 'psw2'); // ...
// We need to test which server authentication variable to use
// because the PHP ISAPI module in IIS acts different from CGI
if(isset($_SERVER['PHP_AUTH_DIGEST']))
{
$auth_data = $_SERVER['PHP_AUTH_DIGEST'];
$isapi = false;
}
elseif(isset($_SERVER['HTTP_AUTHORIZATION']))
{
$auth_data = $_SERVER['HTTP_AUTHORIZATION'];
$isapi = true;
}
else
$auth_data = "";
/* The $_SESSION['error_prompted'] variabile is used to ask
the password again if none given or if the user enters
a wrong auth. informations. */
if (
($auth_data == "") ||
(isset($_SESSION['error_prompted']) && $_SESSION['error_prompted']==true)
)
{
$uniqid = uniqid(""); // Empty argument for backward compatibility
$_SESSION['error_prompted'] = false;
header('HTTP/1.1 401 Unauthorized');
header('WWW-Authenticate: Digest realm="'.$realm.
'" qop="auth" nonce="'.$uniqid.'" opaque="'.md5($realm).'"');
die("You're not allowed to access this page.");
}
else
{
// We need to retrieve authentication informations from the $auth_data variable
if(!$isapi)
{
// CGI doesn't add backslashes to the authentication informations
// and doesn't prepend the "Digest " string before username.
// Furthermore it doesn't enclose the "qop" field between double quotes
preg_match('/username="(?P<username>.*)"' .
',\s*realm="(?P<realm>.*)"' .
',\s*nonce="(?P<nonce>.*)"' .
',\s*uri="(?P<uri>.*)"' .
',\s*response="(?P<response>.*)"' .
',\s*opaque="(?P<opaque>.*)"' .
',\s*qop=(?P<qop>.*)' .
',\s*nc=(?P<nc>.*)' .
',\s*cnonce="(?P<cnonce>.*)"/i', $auth_data, $digest);
}
else
{
// ISAP adds backslashes to the authentication informations
// and prependa the "Digest " string before username.
// Furthermore it encloses the "qop" field between double quotes
preg_match('/digest\susername="(?P<username>.*)"' .
',\s*realm="(?P<realm>.*)"' .
',\s*nonce="(?P<nonce>.*)"' .
',\s*uri="(?P<uri>.*)"' .
',\s*response="(?P<response>.*)"' .
',\s*opaque="(?P<opaque>.*)"' .
',\s*qop=(?P<qop>.*)' .
',\s*nc=(?P<nc>.*)' .
',\s*cnonce="(?P<cnonce>.*)"/i', stripslashes($auth_data), $digest);
// Sometimes ISAPI uses qop="auth", and sometimes it uses qop=auth
$digest['qop'] = str_replace("\"", "", $digest['qop']);
}
if (!isset($users[$digest['username']]))
{
$_SESSION['error_prompted'] = true;
die('Username not valid!');
}
else
{
// This is the valid response expected
$A1 = md5($digest['username'] . ':' . $realm . ':' . $users[$digest['username']]);
$A2 = md5($_SERVER['REQUEST_METHOD'].':'.$digest['uri']);
$valid_response = md5($A1.':'.$digest['nonce'].':'.$digest['nc'].':'.
$digest['cnonce'].':'.$digest['qop'].':'.$A2);
if ($digest['response'] != $valid_response)
{
$error_message = 'Wrong Credentials!';
$_SESSION['error_prompted'] = true;
}
else
{
// Ok, valid user/password
echo 'You are logged in as: ' . $digest['username'];
$logged = true;
}
}
}
?>
yuriry at gmail dot com
09-Mar-2008 12:22
09-Mar-2008 12:22
This example did not work for me too. The problem is only the second branch matches. This is why the trimming was required in the previous post. In addition, if there are spaces in the realm name, the second branch truncates the name.
I started from a simple regular expression to at least get the right number of matches:
preg_match_all('@(\w+)=[^,]+,?@',
$txt, $matches, PREG_SET_ORDER);
The next step was to replace [^,]+ with the right sub-patterns to distinguish between quoted and non-quoted values:
preg_match_all('@(\w+)=(?:([\'"])([^\'"]+)(?:\2)|(\w+)),?@',
$txt, $matches, PREG_SET_ORDER);
Branch ([\'"])([^\'"]+)(?:\2) matches quoted values and branch (\w+) matches non-quoted values.
The problem with the first branch is that the middle sub-pattern ([^\'"]+) matches both single and double quotes, and the author definitely intended to use back-references to solve it. Unfortunately, I could not figure out how to use back-references inside a character class. From the documentation it does not seem possible and I ended up duplicating ([\'"])([^\'"]+)(?:\2) branch to deal with single and double quotes separately:
preg_match_all(
'@(\w+)=(?:([\'])([^\']+)(?:\2)|(["])([^"]+)(?:\4)|(\w+)),?@',
$txt, $matches, PREG_SET_ORDER);
The assignment to the $data array in the foreach loop needs to be changed to reflect different number of sub-patterns:
$data[$m[1]] = $m[6] ? $m[6] : ($m[5] ? $m[5] : $m[3]);
Note that no trimming is required and the expression handles spaces in quoted values. It would also be interesting to know if it is possible to use back-references inside a character class.
Lars Stecken
12-Feb-2008 01:23
12-Feb-2008 01:23
To anybody who tried the digest example above and didn't get it to work.
For me the problem seemed to be the deprecated use of '\' (backslash) in the regex instead of the '$' (Dollar) to indicate a backreference. Also the results have to be trimmed off the remaining double and single quotes.
Here's the working example:
// function to parse the http auth header
function http_digest_parse($txt)
{
// protect against missing data
$needed_parts = array('nonce'=>1, 'nc'=>1, 'cnonce'=>1, 'qop'=>1, 'username'=>1, 'uri'=>1, 'response'=>1);
$data = array();
preg_match_all('@(\w+)=(?:([\'"])([^$2]+)$2|([^\s,]+))@', $txt, $matches, PREG_SET_ORDER);
foreach ($matches as $m) {
$data[$m[1]] = $m[3] ? trim($m[3],"\",'") : trim($m[4],"\",'");
unset($needed_parts[$m[1]]);
}
return $needed_parts ? false : $data;
}
Probably there's a more sophisticated way to trim the quotes within the regex, but I couldn't be bothered :-)
Greets, Lars
mt at shrewsbury dot org dot uk
12-Oct-2007 05:28
12-Oct-2007 05:28
On my servers here, the standard rewrite spell
RewriteRule .* - [E=REMOTE_USER:%{HTTP:Authorization},L]
to set $_SERVER[REMOTE_USER] with digest authentication results in the entire digest being bundled into $_SERVER[REMOTE_USER]
I have used this :
RewriteCond %{HTTP:Authorization} username=\"([^\"]+)\"
RewriteRule .* - [E=REMOTE_USER:%1,L]
And it seems to work successfully.
fordiman at gmail dot com
01-Aug-2007 08:07
01-Aug-2007 08:07
@Whatabrain:
"[E=REMOTE_USER:%{HTTP:Authorization},L] ... didn't work. I couldn't see the variable."
Check $_SERVER['REMOTE_USER'] and $_SERVER['REDIRECT_REMOTE_USER']. It'll be there.
gbelyh at gmail dot com
27-Jul-2007 02:48
27-Jul-2007 02:48
Back to the autherisation in CGI mode. this is the full working example:
# Create the .htaccess file with following contents:
# also you can use the condition (search at this page)
RewriteEngine on
RewriteRule .* - [E=REMOTE_USER:%{HTTP:Authorization},L]
# In the beginning the script checking the authorization place the code:
$userpass = base64_decode(substr($_SERVER["REDIRECT_REMOTE_USER"],6)) ;
$userpass = explode(":", $userpass);
if ( count($userpass) == 2 ){
#this part work not for all.
#print_r($userpass);die; #<- this can help find out right username and password
list($name, $password) = explode(':', $userpass);
$_SERVER['PHP_AUTH_USER'] = $name;
$_SERVER['PHP_AUTH_PW'] = $password;
}
tonwyatt at yahoo dot com
24-Jul-2007 04:27
24-Jul-2007 04:27
Here is my attempt to create a digest authentication class that will log the user in and out without using a cookie,session,db,or file. At the core is this simple code to parse the digest string into variables works for several browsers.
<?php
// explode the digest with multibrowser support by Tony Wyatt 21jun07
public function explodethedigest($instring) {
$quote = '"';
$equal = '=';
$comma = ',';
$space = ' ';
$a = explode( $comma, $instring);
$ax = explode($space, $a[0]);
$b = explode( $equal, $ax[1], 2);
$c = explode( $equal, $a[1], 2);
$d = explode( $equal, $a[2], 2);
$e = explode( $equal, $a[3], 2);
$f = explode( $equal, $a[4], 2);
$g = explode( $equal, $a[5], 2);
$h = explode( $equal, $a[6], 2);
$i = explode( $equal, $a[7], 2);
$j = explode( $equal, $a[8], 2);
$k = explode( $equal, $a[9], 2);
$l = explode( $equal, $a[10], 2);
$parts = array(trim($b[0])=>trim($b[1], '"'), trim($c[0])=>trim($c[1], '"'), trim($d[0])=>trim($d[1], '"'), trim($e[0])=>trim($e[1], '"'), trim($f[0])=>trim($f[1], '"'), trim($g[0])=>trim($g[1], '"'), trim($h[0])=>trim($h[1], '"'), trim($i[0])=>trim($i[1], '"'), trim($j[0])=>trim($j[1], '"'), trim($k[0])=>trim($k[1], '"'), trim($l[0])=>trim($l[1], '"'));
return $parts;
}
?>
Give it a try at http://tokko.kicks-ass.net/tests/ta1.php Log in with user test password pass or user guest password guest. Go to page two for links to the code. Comments, ideas, suggestions, or critique welcome.
Jack Bates
18-Jul-2007 04:01
18-Jul-2007 04:01
In writing the HTTP auth module for the Gallery project, we discovered the following tricks for logging out with HTTP authentication:
Because most web browsers cache HTTP auth credentials, the Gallery logout link didn't work as expected after logging in with HTTP auth. Gallery correctly logged out the active user but the web browser simply logged in again with the next request.
To work around this, the HTTP auth module listens for the Gallery::Logout event and delegates to the httpauth.TryLogout page if necessary: http://gallery.svn.sourceforge.net/viewvc/gallery
/trunk/gallery2/modules/httpauth/TryLogout.inc?view=markup
The TryLogout page tries clearing the browser's authentication cache by as many tricks possible:
* Ask browser to authenticate with bogus authtype:
GalleryUtilities::setResponseHeader('HTTP/1.0 401 Unauthorized', false);
GalleryUtilities::setResponseHeader('WWW-Authenticate: Bogus', false);
* Redirect with random username and password. This won't actually clear the browser's authentication cache but will replace it with an invalid username and password. Since Gallery ignores invalid HTTP auth credentials, this effectively logs the user out.
* Clear Internet Explorer's authentication cache with JavaScript:
try {ldelim}
{* http://msdn.microsoft.com/workshop/author
/dhtml/reference/constants/clearauthenticationcache.asp *}
document.execCommand("ClearAuthenticationCache");
{rdelim} catch (exception) {ldelim}
{rdelim}
The TryLogout page redirects to the FinishLogout page for two resons:
1. To replace the browser's authentication cache with an invalid username and password
2. To check that the user was indeed logged out. If the user was logged out, the FinishLogout page redirects back to the Gallery application. Otherwise it displays a warning advising the user to manually clear their authentication cache (Clear Private Data in Firefox).
The TryLogout page redirects to the FinishLogout page using JavaScript and falls back on a manual link. It can't use a 302 Found status because the page needs to load for the Internet Explorer JavaScript to execute and because we can't put an invalid username and password in a Location: header.
http://codex.gallery2.org/Gallery2:Modules:httpauth
rovok at web dot de
03-Apr-2007 03:05
03-Apr-2007 03:05
People are encouraged NOT to use register_globals, but Example 34.2. of german PHP documentation (http://de.php.net/manual/de/features.http-auth.php) uses register_globals in their example, assumed that the example is the whole script.
There is a <form> which has an <input> with type = "hidden", a name = "SeenBefore" and a value = "1". The Form is submitted by POST, so $SeenBefore should better be accessed by $_POST['SeenBefore'] instead of $SeenBefore.
Dutchdavey
16-Mar-2007 11:28
16-Mar-2007 11:28
My sincere thanks to: webmaster at kratia dot com 21-Feb-2007 01:53
The principle is to not allow an invalid PHP_AUTH_USER to exist.
The following easy peasy example using Oracle is based on his simple genius:
///////////////////////////////////////////////////////////////
//
// do_html_header
//
// This function outputs the html header for the page.
//
//////////////////////////////////////////////////////////////////
function initialize_session()
{
$err=error_reporting(0);
$connection=oci_connect($_SERVER['PHP_AUTH_USER'],
$_SERVER['PHP_AUTH_PW'],$databasename) ;
error_reporting($err);
if (!$connection)
{
header('WWW-Authenticate: Basic Realm="ZEIP1"');
header('HTTP/1.0 401 Unauthorized');
echo "Login Cancelled';
exit;
}
..
Normal Code..
..
}
Nicolas Merlet - admin(at)merletn.org
05-Mar-2007 12:37
05-Mar-2007 12:37
Be careful using http digest authentication (see above, example 34.2) if you have to use the 'setlocale' function *before* validating response with the 'http_digest_parse' function, because there's a conflict with \w in the pattern of 'preg_match_all' function :
In fact, as \w is supposed to be any letter or digit or the underscore character, you must not forgot that this may vary depending on your locale configuration (eg. it accepts accented letters in french)...
Due to this different pattern interpretation by the 'preg_match_all' function, the 'http_digest_parse' function will always return a false result if you have modified your locale (I mean if your locale accepts some extended characters, see http://fr.php.net/manual/en/reference.pcre.pattern.syntax.php for further information).
IMHO, I suggest you not to use setlocale before having your authentication completed...
PS : Here's a non-compatible setlocale declaration...
setlocale ( LC_ALL, 'fr_FR', 'fr', 'FR', 'french', 'fra', 'france', 'French', 'fr_FR.ISO8859-1' ) ;
webmaster at kratia dot com
20-Feb-2007 07:53
20-Feb-2007 07:53
This is the simplest form I found to do a Basic authorization with retries.
<?php
$valid_passwords = array ("mario" => "carbonell");
$valid_users = array_keys($valid_passwords);
$user = $_SERVER['PHP_AUTH_USER'];
$pass = $_SERVER['PHP_AUTH_PW'];
$validated = (in_array($user, $valid_users)) && ($pass == $valid_passwords[$user]);
if (!$validated) {
header('WWW-Authenticate: Basic realm="My Realm"');
header('HTTP/1.0 401 Unauthorized');
die ("Not authorized");
}
// If arrives here, is a valid user.
echo "<p>Welcome $user.</p>";
echo "<p>Congratulation, you are into the system.</p>";
?>
mg at evolution515 dot net
06-Feb-2007 07:20
06-Feb-2007 07:20
Example for digest doesn't work (at least for me):
use this fix:
--------------
preg_match_all('@(\w+)=(?:(([\'"])(.+?)\3|([A-Za-z0-9/]+)))@', $txt, $matches, PREG_SET_ORDER);
foreach ($matches as $m) {
$data[$m[1]] = $m[4] ? $m[4] : $m[5];
unset($needed_parts[$m[1]]);
}
It's also better to but to put the Auth-Digest-Header in a function and call it on unsuccessful authentification again. Otherwise users only have the chance to submit their username/password just one time.
bleuciell at aol dot com
29-Dec-2006 03:51
29-Dec-2006 03:51
For admin , i repair a fault , all is good now
Sorry for my english
It's a piece of code , to give a piece of reflexion about simple auth , we can also cryp login and pass in db , time is here for non-replay , the code isn't finish , but it work , only for reflexion about auth mechanism
<?php
function ky( $txt,$crypt) { $key = md5($crypt); $cpt = 0; $var = "";
for ( $Ctr = 0; $Ctr < strlen($txt); $Ctr++) { if ($cpt == strlen($crypt)) $cpt = 0;
$var.= substr($txt,$Ctr,1) ^ substr($crypt,$cpt,1); $cpt++; } return $var; }
$key = "";$list = 'abcdefghijklmnopqrstuvwxyz0123456789';
for($i = 0; $i< 200; $i++) { $key .= $list{mt_rand() % strlen($list)}; }
function cryp($txt,$key){ srand((double)microtime()*735412); $crypt = crypt(rand(0,3895234));$cpt = 0;$var= "";
for ( $Ctr=0; $Ctr < strlen($txt); $Ctr++ ) { if ($cpt == strlen($crypt))$cpt = 0;
$var.= substr($crypt,$cpt,1).( substr($txt,$Ctr,1) ^ substr($crypt,$cpt,1) ); $cpt++; } return base64_encode(ky($var,$key) ); }
function dcryp($txt,$key){ $txt=ky(base64_decode($txt),$key);$var= "";
for ( $Ctr = 0; $Ctr < strlen($txt); $Ctr++ ) { $md5 = substr($txt,$Ctr,1);$Ctr++; $var.= (substr($txt,$Ctr,1) ^ $md5); }return $var;}
$time= time(); $user = cryp('bubu',$key); $pwd = cryp('bubu-'.$time.'',$key);
function pwd($j,$key){ $x = dcryp($j,$key); $x = explode('-',$x); return $x[0];}
function pwd2($j,$key){ $x = dcryp($j,$key); $x = explode('-',$x); return $x[1];}
function auth(){$realm="Authentification PHPindex";
Header("WWW-Authenticate: Basic realm='".$realm."'");Header("HTTP/1.0 401 Unauthorized");
echo "Vous ne pouvez accéder à cette page"; }
if( !isset($_SERVER['PHP_AUTH_USER']) && !isset($_SERVER['PHP_AUTH_PW']) ) {auth();
} else {
if( $_SERVER['PHP_AUTH_USER'] == dcryp($user,$key) && $_SERVER['PHP_AUTH_PW'] == pwd($pwd,$key) && $time == pwd2($pwd,$key)) {
echo '';
} else{ auth();}}
?>
Whatabrain
10-Nov-2006 10:05
10-Nov-2006 10:05
Back to the problem of authenticating in CGI mode... mcbethh suggested using this to set a local variable in php:
RewriteRule .* - [E=REMOTE_USER:%{HTTP:Authorization},L]
It didn't work. I couldn't see the variable. My solution is pretty round-about, but it works:
RewriteEngine on
RewriteCond %{HTTP:Authorization} !^$
RewriteCond %{REQUEST_METHOD} =GET
RewriteCond %{QUERY_STRING} =""
RewriteRule ^page.php$ page.php?login=%{HTTP:Authorization}$1
This causes the Auth string to be added to the URL if there are no parameters and it's a GET request. This prevents POSTs and parameter lists from being corrupted.
Then, in the PHP script, I store the Auth string as a session cookie.
So the only way to log in to my script is to go to the url with no parameters.
admin at isprohosting dot com
01-Nov-2006 09:21
01-Nov-2006 09:21
There are .htaccess which actually works for us (cPanel + phpsuexec) unless others failed. Perhaps it may help someone.
# PHP (CGI mode) HTTP Authorization with ModRewrite:
RewriteEngine on
RewriteCond %{HTTP:Authorization} ^(.*)
RewriteRule ^(.*) - [E=HTTP_AUTHORIZATION:%1]
Then you need small piece of php code to parse this line and then everything will work like with mod_php:
if (isset($_SERVER['HTTP_AUTHORIZATION']))
{
$ha = base64_decode( substr($_SERVER['HTTP_AUTHORIZATION'],6) );
list($_SERVER['PHP_AUTH_USER'], $_SERVER['PHP_AUTH_PW']) = explode(':', $ha);
unset $ha;
}
Enjoy!
SlamJam
24-Oct-2006 02:28
24-Oct-2006 02:28
I used Louis example (03-Jun-2006) and it works well for me (thanks).
However, I added some lines, to make sure, the user does only get the Authentification-Window a few times:
<?php
$realm = mt_rand( 1, 1000000000)."@YourCompany";
$_SESSION['realm'] = $realm;
// In the beginning, when the realm ist defined:
$_SESSION['CountTrials'] = 1;
?>
And then when it comes to check the authentification (ZEND-Tutorial):
<?php
// Not more than 3 Trials
if (!$auth) {
$_SESSION['CountTrials']++;
if ($_SESSION['CountTrials'] == 4) {
session_destroy() ;
header('Location: noentry.php');
exit ;
} else {
header("WWW-Authenticate: Basic realm=".$_SESSION['realm']);
header("HTTP/1.0 401 Unauthorized");
echo 'Authorization Required.';
exit;
}
} else {
echo '<P>You are authorized!</P>';
}
?>
noentry.php is slightely different from comeagain.php.
roychri at php dot net
10-Oct-2006 11:12
10-Oct-2006 11:12
For PHP with CGI, make sure you put the rewrite rule above any other rewrite rule you might have.
In my case, I put this at the top of the .htaccess (below RewriteEngine On):
RewriteRule .* - [E=REMOTE_USER:%{HTTP:Authorization}]
My symptom was that the REMOTE_USER (or REDIRECT_REMOTE_USER in my case) was not being set at all.
The cause: I had some other RewriteRule that was kickin in and was set as LAST rule.
I hope this helps.
blah at blah dot com
27-Jul-2006 03:46
27-Jul-2006 03:46
Getting PHP Authentication to work with CGI-bin.
You must have mod_rewrite installed for this to work. In the directory (of the file) you want to protect, for the .htaccess file:
# PHP (CGI mode) HTTP Authorization with ModRewrite:
# most right example with header check for non empty:
RewriteEngine on
RewriteCond %{HTTP:Authorization} !^$
RewriteRule ^test.php$ test.php?login=%{HTTP:Authorization}
Change the Rewrite rule to whatever you want it to be. For simplicity, this example only applies to one file, test.php and only if the HTTP Authorization needs to take place.
In the php file:
<?
if (isset($_GET['login'])) {
$d = base64_decode( substr($_GET['login'],6) );
list($name, $password) = explode(':', $d);
echo 'Name:' . $name . "<br>\n";
echo 'Password:' . $password . "<br>\n";
} else {
header('WWW-Authenticate: Basic realm="My Realm"');
header('HTTP/1.0 401 Unauthorized');
echo 'You are not authorized. Bad user, bad!';
exit;
}
?>
You need to get rid of the first 6 characters for some reason, then decode the Auth data from its base64 format. Then it's a simple matter of extracting the data. You can even pass the data to the $_SERVER variables $_SERVER['PHP_AUTH_USER'] and $_SERVER['PHP_AUTH_PW']. These are the variables that get the login data if you have PHP running as an Apache module. This is useful for mods or plugins.
web at kwi dot dk
12-Jul-2006 01:23
12-Jul-2006 01:23
While Digest authentication is still far superior to Basic authentication, there are a number of security issues that one must keep in mind.
In this respect, the Digest example given above is somewhat flawed, because the nonce never times out or otherwise become invalid. It thus becomes a password-equivalent (although to that specific URL only) and can be used by an eavesdropper to fetch the page at any time in the future, thus allowing the attacker to always access the latest version of the page, or (much worse) repeatedly invoke a CGI script -- for instance, if the user requests the URL "/filemanager?delete=somefile", the attacker can repeat this deletion at any point in the future, possibly after the file has been recreated.
And while it might not be possible to change GET data without reauthentication, cookies and POST data *can* be changed.
To protect against the first problem, the nonce can be made to include a timestamp, and a check added to ensure that nonces older than e.g. 30 minutes result in a new authentication request.
To solve the second problem, a one-time only nonce needs to be generated -- that is, all further requests using a particular nonce must be refused.
One way to do this: When the user requests an action such as "deletefile", store a randomly generated nonce in a session variable, issue a 401 authentication challenge with that nonce, and then check against the stored value when receiving the authentication (and clear the session variable).
This way, although a possible eavesdropper receives the nonce and thus gains the ability to perform the action, he can only perform it once -- and the user was going to perform it anyway. (Only the user or the attacker, but not both, gets to perform the action, so it's safe.)
Of course, at some point, the security can only be improved by switching to HTTPS / SSL / TLS (this is for instance the only way to defend against man-in-the-middle attacks). You decide the level of security.
Louis
03-Jun-2006 06:51
03-Jun-2006 06:51
I couldn't get authentication to work properly with any of the examples. Finally, I started from ZEND's tutorial example at:
http://www.zend.com/zend/tut/authentication.php?article=authentication (validate using .htpasswd) and tried to deal with the additional cases. My general conclusion is that changing the realm is the only reliable way to cause the browser to ask again, and I like to thank the person who put that example in the manual, as it got me on the right path. No matter what, the browser refuses to discard the values that it already has in mind otherwise. The problem with changing the realm, of course, is that you don't want to do it within a given session, else it causes a new request for a password. So, here goes, hopefully the spacing isn't too messed up by the cut'n'paste.
I spent the better part of a day getting this to work right. I had a very hard time thinking through what the browser does when it encounters an authentication request: seems to me that it tries to get the password, then reloads the page... so the HTML doesn't get run. At least, this was the case with IE, I haven't tested it with anything else.
<?php
session_start() ;
if (!isset($_SESSION['realm'])) {
$_SESSION['realm'] = mt_rand( 1, 1000000000 ).
" SECOND level: Enter your !!!COMPANY!!! password.";
header( "WWW-Authenticate: Basic realm=".$_SESSION['realm'] );
// Below here runs HTML-wise only if there isn't a $_SESSION,
// and the browser *can't* set $PHP_AUTH_USER... normally
// the browser, having gotten the auth info, runs the page
// again without getting here.
// What I'm basically getting to is that the way to get
// here is to escape past the login screen. I tried
// putting a session_destroy() here originally, but the
// problem is that the PHP runs regardless, so the
// REFRESH seems like the best way to deal with it.
echo "<meta http-equiv=\"REFRESH\"
content=\"0;url=index.php\">" ;
exit;
}
if ($_POST['logout'] == "logout") {
session_destroy() ;
header('Location: comeagain.php');
exit ;
}
// "standard" authentication code here, from the ZEND tutorial above.
comeagain.php is as follows:
<?
session_start();
unset($_SESSION['realm']);
session_destroy();
echo "<html><head><title>Logged Out</title><h1>Logout Page</h1><body>" ;
echo "You have successfully logged out of TOGEN";
echo " at ".date("h:m:s")." on ".date("d F Y") ;
echo "<p><a href=\"index.php\">Login Again</a>" ;
echo "</body></html>" ;
?>
The idea is to be able to trash the session (and thus reset the realm) without prompting the browser to ask again... because it has been redirected to logout.php.
With this combination, I get things to work. Just make sure not to have apache run htpasswd authentication at the same time, then things get really weird :-).
henrik at laurells dot net
01-Jun-2006 02:36
01-Jun-2006 02:36
Above top example for digest mode dosn't work if you have safemode on. You need to add a dash and UID to the compare string to make it work. Something like this;;
$A1 = md5($data['username'].':'.
$realm.'-'.getmyuid().':'.
$users[$data['username']]);
kembl at example dot com
23-May-2006 11:06
23-May-2006 11:06
# PHP (CGI mode) HTTP Authorization with ModRewrite:
# most right example with header check for non empty:
RewriteEngine on
RewriteCond %{HTTP:Authorization} !^$
RewriteRule .* - [E=REMOTE_USER:%{HTTP:Authorization}, \
E=PHP_AUTH_USER:%{HTTP:Authorization},L]
cyberscribe at php dot net
08-May-2006 02:47
08-May-2006 02:47
To implement the Digest authentication mentioned above in PHP < 5.1, try prepending the following:
<?php
$headers = apache_request_headers();
$_SERVER['PHP_AUTH_DIGEST'] = $headers['Authorization'];
?>
or, if you don't like the idea of modifying the global $_SERVER variable directly, just use the first line and then substitute $_SERVER['PHP_AUTH_DIGEST'] in the sample code with $headers['Authorization']. Works great.
ZyX
04-Mar-2006 07:04
04-Mar-2006 07:04
Simple PHP Script to login on a Basic Authentication page.
<?php
/* Access Configuration */
define ('x401_host', 'www.example.com');
define ('x401_port', 80);
define ('x401_user', 'your_username');
define ('x401_pass', 'your_password');
/* Function */
function get401Page($file) {
$out = "GET $file HTTP/1.1\r\n";
$out .= "Host: ".x401_host."t\r\n";
$out .= "Connection: Close\r\n";
$out .= "Authorization: Basic ".base64_encode(x401_user.":".x401_pass)."\r\n";
$out .= "\r\n";
if (!$conex = @fsockopen(x401_host, x401_port, $errno, $errstr, 10))
return 0;
fwrite($conex, $out);
$data = '';
while (!feof($conex)) {
$data .= fgets($conex, 512);
}
fclose($conex);
return $data;
}
/* Code */
if ($source = get401Page('/absolute/path/file.php?get=value')) {
echo $source;
} else {
echo "I can't connect!";
}
?>
djreficul at yahoo dot com
15-Feb-2006 05:14
15-Feb-2006 05:14
Well, I think it's easy to make authentification works correctly. I use a session var to force authentication everytime a user visit the logging area.
<?php
if (!isset ($_SESSION['firstauthenticate'])) {
session_start();
}
function authenticate() {
header('WWW-Authenticate: Basic realm="Sistema autentificación UnoAutoSur"');
header('HTTP/1_0 401 Unauthorized');
// header("Status: 401 Access Denied");
echo "Unauthorized\n";
exit;
}
if (!isset($_SERVER['PHP_AUTH_USER']) || strcmp ($_SERVER['PHP_AUTH_USER'],$user)!=0 ||
!isset ($_SERVER['PHP_AUTH_PW']) || strcmp($_SERVER['PHP_AUTH_PW'],$pass)!=0 || !isset ($_SESSION['firstauthenticate']) || !$_SESSION['firstauthenticate']) {
$_SESSION['firstauthenticate']=true;
authenticate();
} else {
//I destroy the session var now
session_unset();
//Your code below
}
?>
notter at thisaddress dot com
12-Jan-2006 10:19
12-Jan-2006 10:19
A better example of the solution Brian was suggesting [admins: please delete my previous post]
logout.php:
<?php
if (!isset($_GET['quit'])) { ?>
<h4>To complete your log out, please click "OK" then "Cancel" in
this <a href="logout.php?quit=y">log in box</a>. Do not fill in a
password. This should clear your ID and password from the cache of your
browser.
<blockquote>Note: Logging in from this particular box is
disabled!</blockquote>
<p>Go <a href="/">back to the site</a>.</h4>
<?php
} else {
header('WWW-Authenticate: Basic realm="This Realm"');
header('HTTP/1.0 401 Unauthorized');<