Merge pull request #2724 from nextcloud/fix-23591

[downstream] Report failures for SignApp and SignCore

2 files changed, 59 insertions, 18 deletions

diff --git a/lib/private/IntegrityCheck/Checker.php b/lib/private/IntegrityCheck/Checker.php
index cba290e6aa7..419f989fa0f 100644
--- a/lib/private/IntegrityCheck/Checker.php
+++ b/lib/private/IntegrityCheck/Checker.php
@@ -267,16 +267,23 @@ class Checker {
 	public function writeAppSignature($path,
 									  X509 $certificate,
 									  RSA $privateKey) {
-		if(!is_dir($path)) {
-			throw new \Exception('Directory does not exist.');
-		}
-		$iterator = $this->getFolderIterator($path);
-		$hashes = $this->generateHashes($iterator, $path);
-		$signature = $this->createSignatureData($hashes, $certificate, $privateKey);
-		$this->fileAccessHelper->file_put_contents(
-				$path . '/appinfo/signature.json',
+		$appInfoDir = $path . '/appinfo';
+		try {
+			$this->fileAccessHelper->assertDirectoryExists($appInfoDir);
+
+			$iterator = $this->getFolderIterator($path);
+			$hashes = $this->generateHashes($iterator, $path);
+			$signature = $this->createSignatureData($hashes, $certificate, $privateKey);
+				$this->fileAccessHelper->file_put_contents(
+					$appInfoDir . '/signature.json',
 				json_encode($signature, JSON_PRETTY_PRINT)
-		);
+			);
+		} catch (\Exception $e){
+			if (!$this->fileAccessHelper->is_writable($appInfoDir)) {
+				throw new \Exception($appInfoDir . ' is not writable');
+			}
+			throw $e;
+		}
 	}
 
 	/**
@@ -285,17 +292,28 @@ class Checker {
 	 * @param X509 $certificate
 	 * @param RSA $rsa
 	 * @param string $path
+	 * @throws \Exception
 	 */
 	public function writeCoreSignature(X509 $certificate,
 									   RSA $rsa,
 									   $path) {
-		$iterator = $this->getFolderIterator($path, $path);
-		$hashes = $this->generateHashes($iterator, $path);
-		$signatureData = $this->createSignatureData($hashes, $certificate, $rsa);
-		$this->fileAccessHelper->file_put_contents(
-				$path . '/core/signature.json',
+		$coreDir = $path . '/core';
+		try {
+
+			$this->fileAccessHelper->assertDirectoryExists($coreDir);
+			$iterator = $this->getFolderIterator($path, $path);
+			$hashes = $this->generateHashes($iterator, $path);
+			$signatureData = $this->createSignatureData($hashes, $certificate, $rsa);
+			$this->fileAccessHelper->file_put_contents(
+				$coreDir . '/signature.json',
 				json_encode($signatureData, JSON_PRETTY_PRINT)
-		);
+			);
+		} catch (\Exception $e){
+			if (!$this->fileAccessHelper->is_writable($coreDir)) {
+				throw new \Exception($coreDir . ' is not writable');
+			}
+			throw $e;
+		}
 	}
 
 	/**
diff --git a/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php b/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php
index 9e2b76ce11a..a7e378c165e 100644
--- a/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php
+++ b/lib/private/IntegrityCheck/Helpers/FileAccessHelper.php
@@ -53,10 +53,33 @@ class FileAccessHelper {
 	 * Wrapper around file_put_contents($filename, $data)
 	 *
 	 * @param string $filename
-	 * @param $data
-	 * @return int|false
+	 * @param string $data
+	 * @return int
+	 * @throws \Exception
 	 */
 	public function file_put_contents($filename, $data) {
-		return file_put_contents($filename, $data);
+		$bytesWritten = @file_put_contents($filename, $data);
+		if ($bytesWritten === false || $bytesWritten !== strlen($data)){
+			throw new \Exception('Failed to write into ' . $filename);
+		}
+		return $bytesWritten;
+	}
+
+	/**
+	 * @param string $path
+	 * @return bool
+	 */
+	public function is_writable($path) {
+		return is_writable($path);
+	}
+
+	/**
+	 * @param string $path
+	 * @throws \Exception
+	 */
+	public function assertDirectoryExists($path) {
+		if (!is_dir($path)) {
+			throw new \Exception('Directory ' . $path . ' does not exist.');
+		}
 	}
 }