Merge pull request #299 from LDAPAccountManager/feature/275_2fa_login

Feature/275 2fa login

lam/HISTORY

@@ -5,6 +5,7 @@ March 2024 8.7
   -> Cron job to deactivate inactive accounts based on lastBind overlay data (265)
   -> Request access: support Windows groups (266)
   -> Request access: usability improvements (278, 279)
+  -> Self service: passwordless SSO login supported for Okta and OpenID
  - Fixed bugs:
   -> User self registration creates accounts only with SSHA hash (287)
 

lam/docs/manual-sources/chapter-selfService.xml

@@ -202,7 +202,10 @@
               server is responsible to authenticate your users. LAM will use
               the given user name + password for the LDAP login. To setup HTTP
               authentication in Apache please see this <ulink
-              url="http://httpd.apache.org/docs/2.2/howto/auth.html">link</ulink>.</entry>
+              url="http://httpd.apache.org/docs/2.2/howto/auth.html">link</ulink>.
+              If you use Okta or OpenID for 2FA then you can also select to
+              trust the 2FA provider. In this case the user does not need to
+              enter any password in LAM itself (SSO).</entry>
             </row>
 
             <row>

lam/lib/2factor.inc

@@ -7,6 +7,7 @@ use Duo\DuoUniversal\DuoException;
 use Exception;
 use \htmlResponsiveRow;
 use \LAM\LOGIN\WEBAUTHN\WebauthnManager;
+use SelfServiceLoginHandler;
 use \selfServiceProfile;
 use \LAMConfig;
 use \htmlScript;
@@ -595,10 +596,12 @@ class OktaProvider extends BaseProvider {
 	 * @see \LAM\LIB\TWO_FACTOR\BaseProvider::addCustomInput()
 	 */
 	public function addCustomInput(&$row, $userDn) {
+		if (($this->config->loginHandler === null) || !$this->config->loginHandler->managesAuthentication()) {
 			$loginAttribute = $this->getLoginAttributeValue($userDn);
 			if (empty($loginAttribute)) {
 				throw new LAMException('Unable to read login attribute from ' . $userDn);
 			}
+		}
 		if ($this->verificationFailed) {
 			return;
 		}
@@ -656,11 +659,17 @@ class OktaProvider extends BaseProvider {
 		try {
 			$claims = json_decode(base64_decode(explode('.', $accessCode)[1]), true);
 			logNewMessage(LOG_DEBUG, 'Okta claims: ' . print_r($claims, true));
+			$oktaUser = $claims['sub'];
+			if (($this->config->loginHandler !== null) && $this->config->loginHandler->managesAuthentication()) {
+				$this->config->loginHandler->authorize2FaUser($oktaUser);
+			}
+			else {
 				$loginAttribute = $this->getLoginAttributeValue($user);
-			if ($loginAttribute !== $claims['sub']) {
+				if ($loginAttribute !== $oktaUser) {
-				logNewMessage(LOG_ERR, 'User name ' . $loginAttribute . ' does not match claim sub: ' . $claims['sub']);
+					logNewMessage(LOG_ERR, 'User name ' . $loginAttribute . ' does not match claim sub: ' . $oktaUser);
 					return false;
 				}
+			}
 			$this->verificationFailed = false;
 			return true;
 		}
@@ -771,10 +780,13 @@ class OpenIdProvider extends BaseProvider {
 	 * @see \LAM\LIB\TWO_FACTOR\BaseProvider::addCustomInput()
 	 */
 	public function addCustomInput(&$row, $userDn) {
+		$loginAttribute = '';
+		if (($this->config->loginHandler === null) || !$this->config->loginHandler->managesAuthentication()) {
 			$loginAttribute = $this->getLoginAttributeValue($userDn);
 			if (empty($loginAttribute)) {
 				throw new LAMException('Unable to read login attribute from ' . $userDn);
 			}
+		}
 		if ($this->verificationFailed) {
 			return;
 		}
@@ -867,11 +879,17 @@ class OpenIdProvider extends BaseProvider {
 			$tokenSet = $authorizationService->callback($client, $callbackParams, $_GET['redirect_uri']);
 			$claims = $tokenSet->claims();
 			logNewMessage(LOG_DEBUG, print_r($claims, true));
+			$openIdUser = $claims['preferred_username'];
+			if (($this->config->loginHandler !== null) && $this->config->loginHandler->managesAuthentication()) {
+				$this->config->loginHandler->authorize2FaUser($openIdUser);
+			}
+			else {
 				$loginAttribute = $this->getLoginAttributeValue($user);
-			if ($loginAttribute !== $claims['preferred_username']) {
+				if ($loginAttribute !== $openIdUser) {
-				logNewMessage(LOG_ERR, 'User name ' . $loginAttribute . ' does not match claim preferred_username: ' . $claims['preferred_username']);
+					logNewMessage(LOG_ERR, 'User name ' . $loginAttribute . ' does not match claim preferred_username: ' . $openIdUser);
 					return false;
 				}
+			}
 			$this->verificationFailed = false;
 			return true;
 		}
@@ -1250,6 +1268,7 @@ class TwoFactorProviderService {
 			$tfConfig->twoFactorRememberDeviceDuration = $profile->twoFactorRememberDeviceDuration;
 			$tfConfig->twoFactorRememberDevicePassword = $profile->twoFactorRememberDevicePassword;
 		}
+		$tfConfig->loginHandler = $profile->getLoginHandler();
 		return $tfConfig;
 	}
 
@@ -1362,4 +1381,9 @@ class TwoFactorConfiguration {
 	 */
 	public string $twoFactorRememberDevicePassword = '';
 
+	/**
+	 * @var SelfServiceLoginHandler|null login handler
+	 */
+	public ?SelfServiceLoginHandler $loginHandler = null;
+
 }

lam/lib/selfService.inc

@@ -925,6 +925,7 @@ class selfServiceProfile {
 	public function getLoginHandler(): SelfServiceLoginHandler {
 		return match ($this->loginHandler) {
 			SelfServiceHttpAuthLoginHandler::ID => new SelfServiceHttpAuthLoginHandler($this),
+			SelfService2FaLoginHandler::ID => new SelfService2FaLoginHandler($this),
 			default => new SelfServiceUserPasswordLoginHandler($this),
 		};
 	}
@@ -1020,6 +1021,30 @@ interface SelfServiceLoginHandler {
 	 */
 	function getLoginPassword(): string;
 
+	/**
+	 * Returns if the login handler manages authentication on its own.
+	 *
+	 * @return bool manages authentication
+	 */
+	function managesAuthentication(): bool;
+
+	/**
+	 * Returns if the authentication was successful.
+	 * Only valid if managesAuthentication() returns true.
+	 *
+	 * @return bool authentication successful
+	 * @throws LAMException error during authentication
+	 */
+	function isAuthenticationSuccessful(): bool;
+
+	/**
+	 * Authorizes an user that was provided by 2FA provider.
+	 *
+	 * @param string $userName user name
+	 * @throws LAMException error during authentication
+	 */
+	function authorize2FaUser(string $userName): void;
+
 }
 
 /**
@@ -1081,6 +1106,27 @@ class SelfServiceUserPasswordLoginHandler implements SelfServiceLoginHandler {
 		return $_POST['password'];
 	}
 
+	/**
+	 * @inheritDoc
+	 */
+	function managesAuthentication(): bool {
+		return false;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function isAuthenticationSuccessful(): bool {
+		throw new LAMException('Not implemented');
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function authorize2FaUser(string $userName): void {
+		// no action
+	}
+
 }
 
 /**
@@ -1142,4 +1188,137 @@ class SelfServiceHttpAuthLoginHandler implements SelfServiceLoginHandler {
 		return $_SERVER['PHP_AUTH_PW'];
 	}
 
+	/**
+	 * @inheritDoc
+	 */
+	function managesAuthentication(): bool {
+		return false;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function isAuthenticationSuccessful(): bool {
+		throw new LAMException('Not implemented');
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function authorize2FaUser(string $userName): void {
+		// no action
+	}
+
+}
+
+/**
+ * Performs login with pure 2FA.
+ */
+class SelfService2FaLoginHandler implements SelfServiceLoginHandler {
+
+	public const ID = "2fa";
+
+	private selfServiceProfile $profile;
+
+	/**
+	 * Constructor
+	 *
+	 * @param selfServiceProfile $profile profile
+	 */
+	function __construct(selfServiceProfile $profile) {
+		$this->profile = $profile;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function getId(): string {
+		return self::ID;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function addLoginFields(htmlResponsiveRow $content): void {
+		// no input fields
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function getLoginName(): string {
+		return '';
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function getLoginPassword(): string {
+		return '';
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function managesAuthentication(): bool {
+		return true;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function isAuthenticationSuccessful(): bool {
+		if (($this->profile->twoFactorAuthentication !== TwoFactorProviderService::TWO_FACTOR_OKTA)
+			&& ($this->profile->twoFactorAuthentication !== TwoFactorProviderService::TWO_FACTOR_OPENID)) {
+			logNewMessage(LOG_ERR, 'Unsupported 2FA provider: ' . $this->profile->twoFactorAuthentication);
+			return false;
+		}
+		if (!$this->profile->useForAllOperations) {
+			logNewMessage(LOG_ERR, 'Use for all operations must be set');
+			return false;
+		}
+		// authentication will be checked on 2FA page
+		return true;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	function authorize2FaUser(string $userName): void {
+		$bindUser = $this->profile->LDAPUser;
+		if (empty($bindUser)) {
+			throw new LAMException('SelfService2FaLoginHandler', 'No bind user set');
+		}
+		$bindPassword = deobfuscateText($this->profile->LDAPPassword);
+		$server = connectToLDAP($this->profile->serverURL, $this->profile->useTLS);
+		if ($server === null) {
+			throw new LAMException('SelfService2FaLoginHandler', 'Unable to match provided user with LDAP entry - LDAP connect failed');
+		}
+		ldap_set_option($server, LDAP_OPT_REFERRALS, $this->profile->followReferrals);
+		$bind = @ldap_bind($server, $bindUser, $bindPassword);
+		if (!$bind) {
+			throw new LAMException('SelfService2FaLoginHandler', 'Unable to match provided user with LDAP entry - LDAP bind failed');
+		}
+		$filter = '(' . $this->profile->twoFactorAuthenticationAttribute . "=" . ldap_escape($userName) . ')';
+		if (!empty($profile->additionalLDAPFilter)) {
+			$filter = '(&' . $filter . $profile->additionalLDAPFilter . ')';
+		}
+		$result = @ldap_search($server, $this->profile->LDAPSuffix, $filter, ['DN'], 0, 1, 0, LDAP_DEREF_NEVER);
+		if ($result === false) {
+			throw new LAMException('SelfService2FaLoginHandler', 'Unable to match provided user with LDAP entry - LDAP search failed');
+		}
+		$entries = @ldap_get_entries($server, $result);
+		if ($entries === false) {
+			throw new LAMException('SelfService2FaLoginHandler', 'Unable to match provided user with LDAP entry - LDAP search failed');
+		}
+		$info = $entries;
+		cleanLDAPResult($info);
+		if (sizeof($info) === 1) {
+			$userDN = $info[0]['dn'];
+			$_SESSION['selfService_clientDN'] = lamEncrypt($userDN, 'SelfService');
+			return;
+		}
+		throw new LAMException('SelfService2FaLoginHandler', 'Multiple or no results for ' . $userName . ' ' . print_r($info, true));
+	}
+
 }