Refactored size checks for attachments and check base64 upload length

src/Controller/ToolsController.php

@@ -74,7 +74,7 @@ class ToolsController extends AbstractController
             'detailed_error_pages' => $this->getParameter('partdb.error_pages.show_help'),
             'error_page_admin_email' => $this->getParameter('partdb.error_pages.admin_email'),
             'configured_max_file_size' => $settings->system->attachments->maxFileSize,
-            'effective_max_file_size' => $attachmentSubmitHandler->getMaximumAllowedUploadSize(),
+            'effective_max_file_size' => $attachmentSubmitHandler->getMaximumEffectiveUploadSize(),
             'saml_enabled' => $this->getParameter('partdb.saml.enabled'),
 
             //PHP section

src/Form/AttachmentFormType.php

@@ -209,7 +209,7 @@ class AttachmentFormType extends AbstractType
 
     public function finishView(FormView $view, FormInterface $form, array $options): void
     {
-        $view->vars['max_upload_size'] = $this->submitHandler->getMaximumAllowedUploadSize();
+        $view->vars['max_upload_size'] = $this->submitHandler->getMaximumEffectiveUploadSize();
     }
 
     public function getBlockPrefix(): string

src/Services/Attachments/AttachmentSubmitHandler.php

@@ -218,6 +218,14 @@ class AttachmentSubmitHandler
 
         //If no file was uploaded, but we have base64 encoded data, create a file from it
         if (!$file && $upload->data !== null) {
+            if (strlen($upload->data) > $this->getMaximumUserConfiguredUploadSize() * 4 / 3) { //Base64 encoding increases the size of the data by 4/3, so we have to check for that
+                throw new RuntimeException(
+                    sprintf(
+                        'The given base64 data is too big! Maximum size is %.1f MB!',
+                        $this->getMaximumUserConfiguredUploadSize() / 1000 / 1000
+                    ));
+            }
+
             $file = new UploadedBase64EncodedFile(new Base64EncodedFile($upload->data), $upload->filename ?? 'base64');
         }
 
@@ -226,6 +234,15 @@ class AttachmentSubmitHandler
 
         //When a file is given then upload it, otherwise check if we need to download the URL
         if ($file instanceof UploadedFile) {
+            //Check the file size, to avoid uploading too big files.
+            //The file is not necessarily validated as it can also come from an Base64 source
+            if ($file->getSize() > $this->getMaximumUserConfiguredUploadSize()) {
+                throw new RuntimeException(
+                    sprintf(
+                        'The uploaded file is too big! Maximum size is %.1f MB!',
+                        $this->getMaximumUserConfiguredUploadSize() / 1000 / 1000
+                    ));
+            }
 
             $this->upload($attachment, $file, $secure_attachment);
         } elseif ($upload->downloadUrl && $attachment->hasExternal()) {
@@ -402,7 +419,7 @@ class AttachmentSubmitHandler
             $fileHandler = fopen($tmp_path, 'wb');
 
             $bytesDownloaded = 0;
-            $maxSize = $this->attachmentsSettings->getMaxFileSizeInMegabytes() * 1024 * 1024; //Convert to bytes
+            $maxSize = $this->getMaximumUserConfiguredUploadSize(); //We use the maximum user configured size here, PHPs limits dont apply
 
             //Write the downloaded data to file
             foreach ($this->httpClient->stream($response) as $chunk) {
@@ -418,8 +435,8 @@ class AttachmentSubmitHandler
 
                     throw new AttachmentDownloadException(
                         sprintf(
-                            'The downloaded file is too big! Maximum size is %d MB!',
-                            $this->settings->getMaxFileSizeInMegabytes()
+                            'The downloaded file is too big! Maximum size is %.1f MB!',
+                            $maxSize / 1000 / 1000
                         ));
                 }
 
@@ -527,10 +544,10 @@ class AttachmentSubmitHandler
     }
 
     /*
-     * Returns the maximum allowed upload size in bytes.
+     * Returns the maximum effective upload size in bytes.
      * This is the minimum value of Part-DB max_file_size, and php.ini's post_max_size and upload_max_filesize.
      */
-    public function getMaximumAllowedUploadSize(): int
+    public function getMaximumEffectiveUploadSize(): int
     {
         if ($this->max_upload_size_bytes) {
             return $this->max_upload_size_bytes;
@@ -545,6 +562,15 @@ class AttachmentSubmitHandler
         return $this->max_upload_size_bytes;
     }
 
+    /**
+     * Returns the maximum user configured upload size in bytes.
+     * @return int
+     */
+   public function getMaximumUserConfiguredUploadSize(): int
+    {
+        return $this->parseFileSizeString($this->settings->maxFileSize);
+    }
+
     /**
      * Sanitizes the given SVG file, if the attachment is an internal SVG file.
      * @param  Attachment  $attachment

src/Settings/SystemSettings/AttachmentsSettings.php

@@ -65,18 +65,4 @@ class AttachmentsSettings
         envVar: "bool:ATTACHMENT_SHOW_HTML_FILES", envVarMode: EnvVarMode::OVERWRITE
     )]
     public bool $showHTMLAttachments = false;
-
-    public function getMaxFileSizeInMegabytes(): int
-    {
-        $size = $this->maxFileSize;
-        $unit = strtoupper(substr($size, -1));
-        $value = (int) rtrim($size, 'KMG');
-
-        return match ($unit) {
-            'K' => (int) ceil($value / 1024),
-            'M' => $value,
-            'G' => $value * 1024,
-            default => $value, // No unit specified, assume megabytes
-        };
-    }
 }