Add fallback routines for empty secret cases

Signed-off-by: Julius Härtl <jus@bitgrid.net>
nextcloud · Mar 10, 2022 · 81f8719 · 81f8719
1 parent 0825c3e
commit 81f8719
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Showing 4 changed files with 41 additions and 5 deletions.
diff --git a/lib/private/Authentication/Token/PublicKeyTokenProvider.php b/lib/private/Authentication/Token/PublicKeyTokenProvider.php
@@ -185,6 +185,7 @@ public function invalidateToken(string $token) {
 		$this->cache->clear();
 
 		$this->mapper->invalidate($this->hashToken($token));
+		$this->mapper->invalidate($this->hashTokenWithEmptySecret($token));
 	}
 
 	public function invalidateTokenById(string $uid, int $id) {
@@ -301,9 +302,14 @@ private function decrypt(string $cipherText, string $token): string {
 		try {
 			return $this->crypto->decrypt($cipherText, $token . $secret);
 		} catch (\Exception $ex) {
-			// Delete the invalid token
-			$this->invalidateToken($token);
-			throw new InvalidTokenException("Could not decrypt token password: " . $ex->getMessage(), 0, $ex);
+			// Retry with empty secret as a fallback for instances where the secret might not have been set by accident
+			try {
+				return $this->crypto->decrypt($cipherText, $token);
+			} catch (\Exception $ex2) {
+				// Delete the invalid token
+				$this->invalidateToken($token);
+				throw new InvalidTokenException("Could not decrypt token password: " . $ex->getMessage(), 0, $ex2);
+			}
 		}
 	}
 
@@ -326,6 +332,13 @@ private function hashToken(string $token): string {
 		return hash('sha512', $token . $secret);
 	}
 
+	/**
+	 * @depreacted Fallback for instances where the secret might not have been set by accident
+	 */
+	private function hashTokenWithEmptySecret(string $token): string {
+		return hash('sha512', $token);
+	}
+
 	/**
 	 * @throws \RuntimeException when OpenSSL reports a problem
 	 */

diff --git a/lib/private/Security/Crypto.php b/lib/private/Security/Crypto.php
@@ -125,6 +125,15 @@ public function decrypt(string $authenticatedCiphertext, string $password = ''):
 		if ($password === '') {
 			$password = $this->config->getSystemValue('secret');
 		}
+		try {
+			return $this->decryptWithoutSecret($authenticatedCiphertext, $password);
+		} catch (Exception $e) {
+			// Retry with empty secret as a fallback for instances where the secret might not have been set by accident
+			return $this->decryptWithoutSecret($authenticatedCiphertext, '');
+		}
+	}
+
+	private function decryptWithoutSecret(string $authenticatedCiphertext, string $password = ''): string {
 		$hmacKey = $encryptionKey = $password;
 
 		$parts = explode('|', $authenticatedCiphertext);

diff --git a/lib/private/Security/Hasher.php b/lib/private/Security/Hasher.php
@@ -137,6 +137,15 @@ protected function legacyHashVerify($message, $hash, &$newHash = null): bool {
 			return true;
 		}
 
+		// Verify whether it matches a legacy PHPass or SHA1 string
+		// Retry with empty passwordsalt for cases where it was not set
+		$hashLength = \strlen($hash);
+		if (($hashLength === 60 && password_verify($message, $hash)) ||
+			($hashLength === 40 && hash_equals($hash, sha1($message)))) {
+			$newHash = $this->hash($message);
+			return true;
+		}
+
 		return false;
 	}
 

diff --git a/lib/private/Security/VerificationToken/VerificationToken.php b/lib/private/Security/VerificationToken/VerificationToken.php
@@ -84,10 +84,15 @@ public function check(string $token, ?IUser $user, string $subject, string $pass
 		try {
 			$decryptedToken = $this->crypto->decrypt($encryptedToken, $passwordPrefix.$this->config->getSystemValue('secret'));
 		} catch (\Exception $e) {
-			$this->throwInvalidTokenException(InvalidTokenException::TOKEN_DECRYPTION_ERROR);
+			// Retry with empty secret as a fallback for instances where the secret might not have been set by accident
+			try {
+				$decryptedToken = $this->crypto->decrypt($encryptedToken, $passwordPrefix);
+			} catch (\Exception $e2) {
+				$this->throwInvalidTokenException(InvalidTokenException::TOKEN_DECRYPTION_ERROR);
+			}
 		}
 
-		$splitToken = explode(':', $decryptedToken ?? '');
+		$splitToken = explode(':', $decryptedToken);
 		if (count($splitToken) !== 2) {
 			$this->throwInvalidTokenException(InvalidTokenException::TOKEN_INVALID_FORMAT);
 		}