[BUGFIX] Display detected fatal in extension check

In the installer fatals can happen during updates of
very outdated extensions. Many updates can lead to a
redirect to the extension check where the user gets
displayed a message that a fatal has been detected.
But the detected fatal error itself is not displayed.

This patch passes the error as url parameter to the
extension check and displays it there.

Fixes: #54943
Releases: 6.2
Change-Id: I111df5d5411015b21c4b2b5e9be3b83b311c8bc5
Reviewed-on: https://review.typo3.org/26781
Reviewed-by: Helmut Hummel
Tested-by: Helmut Hummel
Reviewed-by: Thomas Maroschik
Reviewed-by: Wouter Wolters
Reviewed-by: Stefan Neufeind
Reviewed-by: Markus Klein
Reviewed-by: Anja Leichsenring
Tested-by: Anja Leichsenring
Tested-by: Wouter Wolters
Reviewed-by: Christian Kuhn
Tested-by: Christian Kuhn

typo3/sysext/install/Classes/Controller/Action/AbstractAction.php

@@ -63,6 +63,11 @@ abstract class AbstractAction {
 	 */
 	protected $postValues = array();
 
+	/**
+	 * @var array Contains the fatal error array of the last request when passed. Schema is the one returned by error_get_last()
+	 */
+	protected $lastError = array();
+
 	/**
 	 * @var array<\TYPO3\CMS\Install\Status\StatusInterface> Optional status message from controller
 	 */
@@ -103,6 +108,7 @@ abstract class AbstractAction {
 			->assign('token', $this->token)
 			->assign('context', $contextService->getContextString())
 			->assign('contextService', $contextService)
+			->assign('lastError', $this->lastError)
 			->assign('messages', $this->messages)
 			->assign('typo3Version', TYPO3_version)
 			->assign('siteName', $GLOBALS['TYPO3_CONF_VARS']['SYS']['sitename'])
@@ -151,6 +157,15 @@ abstract class AbstractAction {
 		$this->postValues = $postValues;
 	}
 
+	/**
+	 * Set the last error array as returned by error_get_last()
+	 *
+	 * @param array $lastError
+	 */
+	public function setLastError(array $lastError) {
+		$this->lastError = $lastError;
+	}
+
 	/**
 	 * Status messages from controller
 	 *

typo3/sysext/install/Classes/Controller/Action/ActionInterface.php

@@ -69,6 +69,13 @@ interface ActionInterface {
 	 */
 	public function setPostValues(array $postValues);
 
+	/**
+	 * Set the last error array as returned by error_get_last()
+	 *
+	 * @param array $lastError
+	 */
+	public function setLastError(array $lastError);
+
 	/**
 	 * Status messages from controller
 	 *

typo3/sysext/install/Classes/Controller/ToolController.php

@@ -129,6 +129,12 @@ class ToolController extends AbstractController {
 					// Add action if specified
 					$parameters[] = 'install[action]=loadExtensions';
 
+					// Add error to display a message what triggered the check
+					$errorEncoded = json_encode($error);
+					$parameters[] = 'install[lastError]=' . rawurlencode($errorEncoded);
+					// We do not use GeneralUtility here to be sure that hash generation works even if that class might not exist any more.
+					$parameters[] = 'install[lastErrorHash]=' . hash_hmac('sha1', $errorEncoded, $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'] . 'InstallToolError');
+
 					$redirectLocation = 'Install.php?' . implode('&', $parameters);
 
 					if (!headers_sent()) {
@@ -148,6 +154,23 @@ class ToolController extends AbstractController {
 		});
 	}
 
+	/**
+	 * Get last error values of install tool.
+	 *
+	 * @return array
+	 */
+	protected function getLastError() {
+		$getVars = \TYPO3\CMS\Core\Utility\GeneralUtility::_GET('install');
+		$lastError = array();
+		if (isset($getVars['lastError']) && isset($getVars['lastErrorHash']) && !empty($GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'])) {
+			$calculatedHash = hash_hmac('sha1', $getVars['lastError'], $GLOBALS['TYPO3_CONF_VARS']['SYS']['encryptionKey'] . 'InstallToolError');
+			if ($calculatedHash === $getVars['lastErrorHash']) {
+				$lastError = json_decode($getVars['lastError'], TRUE);
+			}
+		}
+		return $lastError;
+	}
+
 	/**
 	 * Call an action that needs authentication
 	 *
@@ -173,6 +196,7 @@ class ToolController extends AbstractController {
 		$toolAction->setAction($action);
 		$toolAction->setToken($this->generateTokenForAction($action));
 		$toolAction->setPostValues($this->getPostValues());
+		$toolAction->setLastError($this->getLastError());
 		$this->output($toolAction->handle());
 	}
 }

typo3/sysext/install/Resources/Private/Partials/Action/Tool/ImportantActions/LastError.html

+<f:if condition="{lastError}">
+	<div class="typo3-message message-warning">
+		<div class="header-container">
+			<div class="message-header">
+				<strong>Detected Fatal Error</strong>
+			</div>
+			<div class="message-body">
+				{lastError.message} in {lastError.file} on line {lastError.line}
+			</div>
+		</div>
+	</div>
+</f:if>
\ No newline at end of file

typo3/sysext/install/Resources/Private/Templates/Action/Tool/LoadExtensions.html

@@ -13,6 +13,8 @@
 		are unloaded, you can restart the initial action to proceed your request.
 	</p>
 
+	<f:render partial="Action/Tool/ImportantActions/LastError" arguments="{lastError: lastError}"/>
+
 	<hr />
 	<f:render partial="Action/Tool/ImportantActions/ExtensionCompatibilityTester" arguments="{_all}"/>
 	<script type="text/javascript">