From 05916f4238315a3e74eaa367dc82bc902b61c6b5 Mon Sep 17 00:00:00 2001
From: Luca Iadicicco <info@lucaiadicicco.it>
Date: Tue, 16 Jul 2024 18:27:09 +0200
Subject: [PATCH] Add DKIM private key settings to `.env` and
 `/config/mail.php`. Ensure correct key format. Log errors if private key
 retrieval fails.

---
 README.md      | 28 +++++++++-------------------
 src/Mailer.php | 29 ++++++++++++++++-------------
 2 files changed, 25 insertions(+), 32 deletions(-)

diff --git a/README.md b/README.md
index 83f5028..59a218f 100644
--- a/README.md
+++ b/README.md
@@ -27,9 +27,9 @@ composer require hostbrook/laravel-dkim
 HostBrook\LaravelDkim\DkimMailServiceProvider::class,
 ```
 
-3. Add your DKIM private key settings in `/.env` or in `/config/mail.php`. The priority of DKIM settings is from `/.env` file.
+1. Add your DKIM private key settings in `/.env` and in `/config/mail.php`. 
 
-   3.1. The syntax, if you want to add DKIM private key settings in `/.env` file:
+   3.1. Add DKIM private key settings in `/.env` file:
 
    ```
    DKIM_SELECTOR="selector1"
@@ -38,7 +38,7 @@ HostBrook\LaravelDkim\DkimMailServiceProvider::class,
    DKIM_PRIVATE_KEY="/storage/app/dkim/private_key.txt"
    ```
 
-   As an option, you can add the full RSA Private Key to the `.env` file, for example:
+   Or, add the full RSA Private Key to the `.env` file, for example:
 
    ```
    DKIM_PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----
@@ -48,28 +48,18 @@ HostBrook\LaravelDkim\DkimMailServiceProvider::class,
    -----END RSA PRIVATE KEY-----"
    ```
 
-   3.2. The syntax, if you want to add DKIM private key settings in `/config/mail.php` file:
+   3.2. Then in `/config/mail.php` file:
 
    ```
-   'dkim_selector' => 'selector1',
-   'dkim_domain' => 'domain.name',
-   'dkim_passphrase' => '', // leave empty if you didn’t protect the private key
-   'dkim_private_key' => '/storage/app/dkim/private_key.txt',
-   ```
-
-   As an option, you can add the full RSA Private Key to the `/config/mail.php` file, for example:
-
-   ```
-   'dkim_private_key' => '-----BEGIN RSA PRIVATE KEY-----
-   MIIEowIBAAKCAQEAq1SCAScet736Rr/f36OYUo8cRziq4v2uq6kNs5wzEaaqUAoh
-   ...
-   ENwDlqtgpM9D7YznrL6W9NH7fdSwmz2Ux0frY6weuBx/VSeJn1fb
-   -----END RSA PRIVATE KEY-----',
+    'dkim_private_key' => env('DKIM_PRIVATE_KEY', ''),
+    'dkim_domain' => env('DKIM_DOMAIN', ''),
+    'dkim_selector' => env('DKIM_SELECTOR', 'default'),
+    'dkim_passphrase' => env('DKIM_PASSPHRASE', ''),
    ```
 
 ## Notes and recommendations
 
-- No matter where you keep the RSA Private Key, in `/.env` file or in `/config/mail.php` file or in a text file, everything between two instances `'-----BEGIN RSA PRIVATE KEY-----'` and `'-----END RSA PRIVATE KEY-----'` must be right up to the start of the line!
+- No matter where you keep the RSA Private Key, everything between two instances `'-----BEGIN RSA PRIVATE KEY-----'` and `'-----END RSA PRIVATE KEY-----'` must be right up to the start of the line!
 - It is not recommended to keep private key directly in the `/config/mail.php` file for security reasons especially if your project is not in the private repository.
 - If you would like to keep RSA Private key in a text file, the path to the text file must be relative to the project base path (like in the example above).
 
diff --git a/src/Mailer.php b/src/Mailer.php
index f950d81..6fa824f 100644
--- a/src/Mailer.php
+++ b/src/Mailer.php
@@ -42,7 +42,7 @@ public function send($view, array $data = [], $callback = null): ?SentMessage
         // Once we have retrieved the view content for the e-mail we will set the body
         // of this message using the HTML type, which will provide a simple wrapper
         // to creating view based emails that are able to receive arrays of data.
-        if (! is_null($callback)) {
+        if (!is_null($callback)) {
             $callback($message);
         }
 
@@ -59,25 +59,28 @@ public function send($view, array $data = [], $callback = null): ?SentMessage
         // one final chance to stop this message and then we will send it to all of
         // its recipients. We will then fire the sent event for the sent message.
         $symfonyMessage = $message->getSymfonyMessage();
+        $privateKey = config('mail.dkim_private_key', '');
+        if ($privateKey != null)
+            try {
+                if (File::exists(base_path() . $privateKey))
+                    $privateKey = File::get(base_path() . $privateKey);
+            } catch (\Exception $ex) {
+                Log::error($ex->getMessage());
+                return null;
+            }
 
-        $privateKey = env('DKIM_PRIVATE_KEY') ? env('DKIM_PRIVATE_KEY','') : config('mail.dkim_private_key','');
-        if (File::exists(base_path().$privateKey)) $privateKey = File::get(base_path().$privateKey);
-
-        $domain = env('DKIM_DOMAIN') ? env('DKIM_DOMAIN','') : config('mail.dkim_domain','');
-        $selector = env('DKIM_SELECTOR') ? env('DKIM_SELECTOR','') : config('mail.dkim_selector','');
-        $passphrase = env('DKIM_PASSPHRASE') ? env('DKIM_PASSPHRASE','') : config('mail.dkim_passphrase','');
+        $domain = config('mail.dkim_domain', '');
+        $selector = config('mail.dkim_selector', '');
+        $passphrase = config('mail.dkim_passphrase', '');
 
         // Sign emails if values of domain, selector and passphrase exist:
         if (!$privateKey) {
             Log::warning('The message hasn\'t been signed with DKIM: No private key set.');
-        }
-        elseif (!$domain) {
+        } elseif (!$domain) {
             Log::warning('The message hasn\'t been signed with DKIM: No domain set.');
-        }
-        elseif (!$selector) {
+        } elseif (!$selector) {
             Log::warning('The message hasn\'t been signed with DKIM: No selector set.');
-        }
-        else {
+        } else {
             $signer = new DkimSigner($privateKey, $domain, $selector, [], $passphrase);
             $signedEmail = $signer->sign($message->getSymfonyMessage());
             $symfonyMessage->setHeaders($signedEmail->getHeaders());