Preventive measure if permission is denied for firewall file

Author: deleugpn

app/Disk.php

@@ -9,31 +9,39 @@
 class Disk
 {
     /**
-     * Write a file into Disk. Creates if it doesn't exist.
+     * Check whether a file can be written in the Disk.
      *
      * @param File $file
+     * @return bool
      */
-    public function write(File $file)
+    public function writable(File $file)
     {
-        if (!is_file($file->path)) {
-            $this->touch($file->path);
-        }
-
-        $this->put($file->path, $file->content());
+        return $this->isWritable($file->path);
     }
 
-    public function checksum(File $file)
+    /**
+     * Write a file into Disk. Creates if it doesn't exist.
+     *
+     * @param File $file
+     */
+    public function write(File $file)
     {
-        if (is_file($file->path)) {
-            return md5_file($file->path);
+        if (! $this->fileExists($file->path)) {
+            $this->touch($file->path);
         }
 
-        return md5('');
+        $this->put($file->path, $file->content);
     }
 
+    /**
+     * Check if the content in the database match the content in the Disk file.
+     *
+     * @param File $file
+     * @return bool
+     */
     public function match(File $file)
     {
-        return $this->checksum($file) == $file->checksum;
+        return $this->hash($file->path) == $file->checksum;
     }
 
     protected function touch($filepath)
@@ -66,11 +74,55 @@ protected function recursiveMakeDirectory($filepath)
     {
         try {
             $directory = dirname($filepath);
-            if (!is_dir($directory)) {
+            if (! is_dir($directory)) {
                 mkdir($directory, 0755, true);
             }
         } catch (ErrorException $e) {
             throw new PermissionDeniedException($filepath);
         }
     }
+
+    /**
+     * Return true if the file or directory exists.
+     *
+     * @param $path
+     * @return bool
+     */
+    protected function fileExists($path)
+    {
+        return file_exists($path);
+    }
+
+    protected function hash($path)
+    {
+        if ($this->fileExists($path)) {
+            return md5_file($path);
+        }
+
+        return md5('');
+    }
+
+    protected function isDirectory($path)
+    {
+        return is_dir($path);
+    }
+
+    /**
+     * Check if a path is writable.
+     *
+     * @param string $path
+     * @return bool
+     */
+    protected function isWritable($path)
+    {
+        // If the file or directory exists, we can just check if it's writable.
+        if ($this->fileExists($path)) {
+            return is_writable($path);
+        }
+
+        // Since it doesn't exist, let's check if we have permission in the parent directory
+        $directory = dirname($path);
+
+        return $this->isWritable($directory);
+    }
 }

app/Models/File.php

@@ -11,6 +11,7 @@
  * @property Collection sections
  * @property string path
  * @property string checksum
+ * @property string content
  */
 class File extends Model
 {
@@ -28,7 +29,7 @@ public function sections()
         return $this->hasMany(Section::class, 'file_id');
     }
 
-    public function content()
+    public function getContentAttribute()
     {
         $this->loadMissing('sections');
 
@@ -40,7 +41,7 @@ public function getChecksumAttribute()
     {
         // @TODO: Maybe improve performance by adding a checksum column to the file table and keeping it up to date with content change
         // instead of recalculating it real time.
-        return md5($this->content());
+        return md5($this->content);
     }
 
     public function getSynchronizedAttribute()

config/app.php

@@ -15,7 +15,7 @@
 
     'name' => env('APP_NAME', 'Thunderwall'),
 
-    'version' => '0.0.13',
+    'version' => '0.0.14',
 
     /*
     |--------------------------------------------------------------------------
@@ -229,6 +229,7 @@
         'Validator' => Illuminate\Support\Facades\Validator::class,
         'View' => Illuminate\Support\Facades\View::class,
 
+        'Disk' => Facades\App\Disk::class
     ],
 
 ];

resources/views/app/files/create.blade.php

@@ -5,6 +5,12 @@
         <div class="row">
             <div class="col-md-8 col-md-offset-2">
 
+                @if(! Disk::writable($file))
+                    <div class="alert alert-danger">
+                        <i class="fa fa-warning"></i> {{ __('Permission denied to file :file', ['file' => $file->path]) }}
+                    </div>
+                @endif
+
                 <form method="POST" action="/modules/firewall/{{ $file->id }}">
                     {{ method_field('PUT') }}
                     {{ csrf_field() }}
@@ -27,11 +33,13 @@
                             @endforeach
                         </div>
 
-                        <div class="panel-footer">
-                            <div class="form-group">
-                                <input type="submit" class="btn btn-primary" value="{{ __('Apply') }}">
+                        @if(Disk::writable($file))
+                            <div class="panel-footer">
+                                <div class="form-group">
+                                    <input type="submit" class="btn btn-primary" value="{{ __('Apply') }}">
+                                </div>
                             </div>
-                        </div>
+                        @endif
                     </div>
 
                 </form>