Option to automatically strip EXIF metadata from JPEGs

inc/config.php

@@ -418,6 +418,9 @@
 	//	- 'convert'	The command line version of ImageMagick (`convert`). Fixes most of the bugs in PHP Imagick.
 	$config['thumb_method'] = 'gd';
 	
+	// Strip EXIF metadata from JPEG files
+	$config['strip_exif'] = false;
+	
 	// Regular expression to check for IE MIME type detection XSS exploit. To disable, comment the line out
 	// https://github.com/savetheinternet/Tinyboard/issues/20
 	$config['ie_mime_type_detection'] = '/<(?:body|head|html|img|plaintext|pre|script|table|title|a href|channel|scriptlet)/i';

inc/image.php

@@ -166,6 +166,9 @@ class ImageImagick extends ImageBase {
 		}
 	}
 	public function to($src) {
+		if ($config['strip_exif']) {
+			$this->image->stripImage();
+		}
 		if (preg_match('/\.gif$/i', $src))
 			$this->image->writeImages($src, true);
 		else
@@ -236,9 +239,14 @@ class ImageConvert extends ImageBase {
 		}
 	}
 	public function to($src) {
+		global $config;
+		
 		if (!$this->temp) {
-			// $config['redraw_image']
-			shell_exec('convert ' . escapeshellarg($this->src) . ' ' . escapeshellarg($src));
+			if ($config['strip_exif']) {
+				shell_exec('convert ' . escapeshellarg($this->src) . ' -strip ' . escapeshellarg($src));
+			} else {
+				shell_exec('convert ' . escapeshellarg($this->src) . ' ' . escapeshellarg($src));
+			}
 		} else {
 			rename($this->temp, $src);
 			chmod($src, 0664);

post.php

@@ -420,10 +420,11 @@ if (isset($_POST['delete'])) {
 				error($config['error']['maxsize']);
 			}
 			
-			// The following code corrects the image orientation based on EXIF.
-			// Currently only works with the 'convert' option selected but it could easily be expanded to work with the rest if you can be bothered.
-			if ($config['thumb_method'] == 'convert') {
-				if ($post['extension'] == 'jpg' || $post['extension'] == 'jpeg') {
+			
+			if ($post['extension'] == 'jpg' || $post['extension'] == 'jpeg') {
+				// The following code corrects the image orientation.
+				// Currently only works with the 'convert' option selected but it could easily be expanded to work with the rest if you can be bothered.
+				if ($config['thumb_method'] == 'convert') {
 					$exif = exif_read_data($upload);
 					if (isset($exif['Orientation']) && $exif['Orientation'] != 1) {
 						shell_exec('convert ' . escapeshellarg($upload) . ' -auto-orient ' . escapeshellarg($upload));							
@@ -473,7 +474,7 @@ if (isset($_POST['delete'])) {
 				$thumb->_destroy();
 			}
 			
-			if ($config['redraw_image']) {
+			if ($config['redraw_image'] || ($config['strip_exif'] && ($post['extension'] == 'jpg' || $post['extension'] == 'jpeg'))) {
 				$image->to($post['file']);
 				$dont_copy_file = true;
 			}