From e49037024c5a92ddb76ee59d4ca90e2fb84327af Mon Sep 17 00:00:00 2001
From: "Nathan J. Brauer" <nathanbrauer@gmail.com>
Date: Thu, 9 Nov 2023 14:53:21 -0800
Subject: [PATCH 1/2] FIX Infinite recursion sanity checks with more helpful
 error messages (#214)

* Infinite recursion protections
Adds sanity checks to prevent unanticipated internal infinite recursions (now throws Exceptions with helpful messages; previously timed out or hit memory limits)

* Accepting coding standards

Co-authored-by: Steve Boyd <emteknetnz@gmail.com>

* MNT Linting

---------

Co-authored-by: Steve Boyd <emteknetnz@gmail.com>
---
 src/Controllers/ShareDraftController.php | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/Controllers/ShareDraftController.php b/src/Controllers/ShareDraftController.php
index 3ea1914..883a228 100644
--- a/src/Controllers/ShareDraftController.php
+++ b/src/Controllers/ShareDraftController.php
@@ -52,6 +52,8 @@ class ShareDraftController extends Controller
      */
     protected static $isViewingPreview = false;
 
+    private array $redirectRecursionIterations = [];
+
     /**
      * @return bool
      */
@@ -172,8 +174,8 @@ private function getRenderedPageByURL(string $url): HTTPResponse
         $variables['_SERVER']['HTTP_USER_AGENT'] =
             isset($variables['_SERVER']['HTTP_USER_AGENT']) &&
             $variables['_SERVER']['HTTP_USER_AGENT']
-            ? $variables['_SERVER']['HTTP_USER_AGENT']
-            : 'CLI';
+                ? $variables['_SERVER']['HTTP_USER_AGENT']
+                : 'CLI';
 
         Environment::setVariables($variables);
 
@@ -183,6 +185,15 @@ private function getRenderedPageByURL(string $url): HTTPResponse
         $response = Director::singleton()->handleRequest($pageRequest);
 
         if ($response->isRedirect()) {
+            if (in_array($url, $this->redirectRecursionIterations)) {
+                throw new \Exception("Infinite recursion detected." . $this->getRedirectRecursionIterationsLog($url));
+            }
+
+            $this->redirectRecursionIterations[] = $url;
+            if (count($this->redirectRecursionIterations) >= 30) {
+                throw new \Exception("Max redirect recursions reached." . $this->getRedirectRecursionIterationsLog());
+            }
+
             // The redirect will probably be Absolute URL so just want the path
             $newUrl = parse_url($response->getHeader('location') ?? '', PHP_URL_PATH);
 
@@ -192,6 +203,13 @@ private function getRenderedPageByURL(string $url): HTTPResponse
         return $response;
     }
 
+    private function getRedirectRecursionIterationsLog(string $appendUrl = ''): string
+    {
+        return "\n\nRedirected URLs stack: \n"
+            . implode("\n", $this->redirectRecursionIterations)
+            . ($appendUrl ? "\n$appendUrl" : '');
+    }
+
     /**
      * @return DBHTMLText
      */

From 58a795e50a940c29bbdd8761ce50c010830f79ec Mon Sep 17 00:00:00 2001
From: "Nathan J. Brauer" <nathan@marketera.com>
Date: Sun, 15 Oct 2023 17:50:19 -0700
Subject: [PATCH 2/2] Fixes internal infinite recursion on Nginx/PHP-FPM
 environments

---
 src/Controllers/ShareDraftController.php | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Controllers/ShareDraftController.php b/src/Controllers/ShareDraftController.php
index 883a228..51870de 100644
--- a/src/Controllers/ShareDraftController.php
+++ b/src/Controllers/ShareDraftController.php
@@ -179,6 +179,11 @@ private function getRenderedPageByURL(string $url): HTTPResponse
 
         Environment::setVariables($variables);
 
+        // This extra step required for PHP-FPM/Nginx implementations
+        Environment::setEnv('REQUEST_URI', $url);
+        Environment::setEnv('REQUEST_METHOD', 'GET');
+        Environment::setEnv('HTTP_USER_AGENT', $variables['_SERVER']['HTTP_USER_AGENT']);
+
         // Health-check prior to creating environment
         $pageRequest = HTTPRequestBuilder::createFromVariables($variables, @file_get_contents('php://input'));