From: Robin Gustafsson <robin@rgson.se>
Date: Sat, 28 May 2022 20:39:10 +0200
Subject: Handle the case of missing DES-ECB cipher support

One feature requires the DES-ECB cipher from the OpenSSL extension,
which is nowadays deemed insecure and thus no longer supported.
---
 lib/classes/Swift/Transport/Esmtp/Auth/NTLMAuthenticator.php    | 3 +++
 tests/unit/Swift/Transport/Esmtp/Auth/NTLMAuthenticatorTest.php | 4 ++++
 2 files changed, 7 insertions(+)

diff --git a/lib/classes/Swift/Transport/Esmtp/Auth/NTLMAuthenticator.php b/lib/classes/Swift/Transport/Esmtp/Auth/NTLMAuthenticator.php
index 41931fd..d62639f 100644
--- a/lib/classes/Swift/Transport/Esmtp/Auth/NTLMAuthenticator.php
+++ b/lib/classes/Swift/Transport/Esmtp/Auth/NTLMAuthenticator.php
@@ -549,6 +549,9 @@ class Swift_Transport_Esmtp_Auth_NTLMAuthenticator implements Swift_Transport_Es
      */
     protected function desEncrypt($value, $key)
     {
+        if (!in_array('des-ecb', openssl_get_cipher_methods())) {
+            throw new LogicException('The OpenSSL extension must provide the DES-ECB cipher to use certain features of the NTLM authenticator.');
+        }
         return substr(openssl_encrypt($value, 'DES-ECB', $key, \OPENSSL_RAW_DATA), 0, 8);
     }
 
diff --git a/tests/unit/Swift/Transport/Esmtp/Auth/NTLMAuthenticatorTest.php b/tests/unit/Swift/Transport/Esmtp/Auth/NTLMAuthenticatorTest.php
index 2337149..96c94d7 100644
--- a/tests/unit/Swift/Transport/Esmtp/Auth/NTLMAuthenticatorTest.php
+++ b/tests/unit/Swift/Transport/Esmtp/Auth/NTLMAuthenticatorTest.php
@@ -29,6 +29,10 @@ class Swift_Transport_Esmtp_Auth_NTLMAuthenticatorTest extends \SwiftMailerTestC
 
     public function testLMv1Generator()
     {
+        if (!in_array('des-ecb', openssl_get_cipher_methods())) {
+            $this->markTestSkipped('Need OpenSSL extension with the DES-ECB cipher to run this test.');
+        }
+
         $password = 'test1234';
         $challenge = 'b019d38bad875c9d';
         $lmv1 = '1879f60127f8a877022132ec221bcbf3ca016a9f76095606';