Use random_bytes

Since we don't care if it is human readbale.
The code is backwards compatible with the old format.

Signed-off-by: Roeland Jago Douma <roeland@famdouma.nl>

diff --git a/lib/private/Security/Crypto.php b/lib/private/Security/Crypto.php
index 10a52d9fc8f76f0e34b7b699cf48db3bc212c56c..154448281b9a35ab00863ec4837fa1ad86335243 100644 (file)
--- a/lib/private/Security/Crypto.php
+++ b/lib/private/Security/Crypto.php
@@ -52,17 +52,14 @@ class Crypto implements ICrypto {
        private $ivLength = 16;
        /** @var IConfig */
        private $config;
-       /** @var ISecureRandom */
-       private $random;
 
        /**
         * @param IConfig $config
         * @param ISecureRandom $random
         */
-       public function __construct(IConfig $config, ISecureRandom $random) {
+       public function __construct(IConfig $config) {
                $this->cipher = new AES();
                $this->config = $config;
-               $this->random = $random;
        }
 
        /**
@@ -95,13 +92,14 @@ class Crypto implements ICrypto {
                }
                $this->cipher->setPassword($password);
 
-               $iv = $this->random->generate($this->ivLength);
+               $iv = \random_bytes($this->ivLength);
                $this->cipher->setIV($iv);
 
                $ciphertext = bin2hex($this->cipher->encrypt($plaintext));
+               $iv = bin2hex($iv);
                $hmac = bin2hex($this->calculateHMAC($ciphertext.$iv, $password));
 
-               return $ciphertext.'|'.$iv.'|'.$hmac;
+               return $ciphertext.'|'.$iv.'|'.$hmac.'|2';
        }
 
        /**
@@ -119,7 +117,8 @@ class Crypto implements ICrypto {
                $this->cipher->setPassword($password);
 
                $parts = explode('|', $authenticatedCiphertext);
-               if (\count($parts) !== 3) {
+               $partCount = \count($parts);
+               if ($partCount < 3 || $partCount > 4) {
                        throw new \Exception('Authenticated ciphertext could not be decoded.');
                }
 
@@ -127,6 +126,13 @@ class Crypto implements ICrypto {
                $iv = $parts[1];
                $hmac = hex2bin($parts[2]);
 
+               if ($partCount === 4) {
+                       $version = $parts[3];
+                       if ($version === '2') {
+                               $iv = hex2bin($iv);
+                       }
+               }
+
                $this->cipher->setIV($iv);
 
                if (!hash_equals($this->calculateHMAC($parts[0] . $parts[1], $password), $hmac)) {

diff --git a/tests/lib/Security/CryptoTest.php b/tests/lib/Security/CryptoTest.php
index a6f4902594a8a18a04df0074feb57dd090bf714f..dbdf6f6a195b8ca3851cfe0e63610447bf8c1c77 100644 (file)
--- a/tests/lib/Security/CryptoTest.php
+++ b/tests/lib/Security/CryptoTest.php
@@ -24,7 +24,7 @@ class CryptoTest extends \Test\TestCase {
 
        protected function setUp(): void {
                parent::setUp();
-               $this->crypto = new Crypto(\OC::$server->getConfig(), \OC::$server->getSecureRandom());
+               $this->crypto = new Crypto(\OC::$server->getConfig());
        }
 
        /**
@@ -35,7 +35,7 @@ class CryptoTest extends \Test\TestCase {
                $this->assertEquals($stringToEncrypt, $this->crypto->decrypt($ciphertext));
        }
 
-       
+
        public function testWrongPassword() {
                $this->expectException(\Exception::class);
                $this->expectExceptionMessage('HMAC does not match.');
@@ -51,7 +51,7 @@ class CryptoTest extends \Test\TestCase {
                $this->assertEquals($stringToEncrypt, $this->crypto->decrypt($encryptedString, 'ThisIsAVeryS3cur3P4ssw0rd'));
        }
 
-       
+
        public function testWrongIV() {
                $this->expectException(\Exception::class);
                $this->expectExceptionMessage('HMAC does not match.');
@@ -60,7 +60,7 @@ class CryptoTest extends \Test\TestCase {
                $this->crypto->decrypt($encryptedString, 'ThisIsAVeryS3cur3P4ssw0rd');
        }
 
-       
+
        public function testWrongParameters() {
                $this->expectException(\Exception::class);
                $this->expectExceptionMessage('Authenticated ciphertext could not be decoded.');
@@ -68,4 +68,11 @@ class CryptoTest extends \Test\TestCase {
                $encryptedString = '1|2';
                $this->crypto->decrypt($encryptedString, 'ThisIsAVeryS3cur3P4ssw0rd');
        }
+
+       public function testLegacy() {
+               $cipherText = 'e16599188e3d212f5c7f17fdc2abca46|M1WfLAxbcAmITeD6|509457885d6ca5e6c3bfd3741852687a7f2bffce197f8d5ae97b65818b15a1b7f616b68326ff312371540f4ca8ac55f8e2de4aa13aab3474bd3431e51214e3ee';
+               $password = 'mypass';
+
+               $this->assertSame('legacy test', $this->crypto->decrypt($cipherText, $password));
+       }
 }