Fixes #4895: Output valid ETag and Expires headers

6 files changed, 16 insertions, 20 deletions

diff --git a/engine/handlers/cache_handler.php b/engine/handlers/cache_handler.php
index b332ec379..7706c2c92 100644
--- a/engine/handlers/cache_handler.php
+++ b/engine/handlers/cache_handler.php
@@ -64,7 +64,7 @@ $ts = $matches[4];
 
 // If is the same ETag, content didn't changed.
 $etag = $ts;
-if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == $etag) {
+if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == "\"$etag\"") {
 	header("HTTP/1.1 304 Not Modified");
 	exit;
 }
@@ -80,10 +80,10 @@ switch ($type) {
 		break;
 }
 
-header('Expires: ' . date('r', strtotime("+6 months")), true);
+header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+6 months")), true);
 header("Pragma: public", true);
 header("Cache-Control: public", true);
-header("ETag: $etag");
+header("ETag: \"$etag\"");
 
 $filename = $dataroot . 'views_simplecache/' . md5($viewtype . $view);
 
diff --git a/engine/lib/elgglib.php b/engine/lib/elgglib.php
index 974f38aad..dd3cba25d 100644
--- a/engine/lib/elgglib.php
+++ b/engine/lib/elgglib.php
@@ -1885,7 +1885,7 @@ function elgg_cacheable_view_page_handler($page, $type) {
 		header("Content-type: $content_type");
 
 		// @todo should js be cached when simple cache turned off
-		//header('Expires: ' . date('r', time() + 864000));
+		//header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+10 days")), true);
 		//header("Pragma: public");
 		//header("Cache-Control: public");
 		//header("Content-Length: " . strlen($return));
diff --git a/mod/file/thumbnail.php b/mod/file/thumbnail.php
index 35bf8c7f7..851f13a8f 100644
--- a/mod/file/thumbnail.php
+++ b/mod/file/thumbnail.php
@@ -46,7 +46,7 @@ if ($simpletype == "image") {
 
 		// caching images for 10 days
 		header("Content-type: $mime");
-		header('Expires: ' . date('r',time() + 864000));
+		header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+10 days")), true);
 		header("Pragma: public", true);
 		header("Cache-Control: public", true);
 		header("Content-Length: " . strlen($contents));
diff --git a/mod/groups/icon.php b/mod/groups/icon.php
index 1bd240ea6..ebdc1eb6d 100644
--- a/mod/groups/icon.php
+++ b/mod/groups/icon.php
@@ -18,7 +18,7 @@ if (!($group instanceof ElggGroup)) {
 
 // If is the same ETag, content didn't changed.
 $etag = $group->icontime . $group_guid;
-if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == $etag) {
+if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == "\"$etag\"") {
 	header("HTTP/1.1 304 Not Modified");
 	exit;
 }
@@ -46,9 +46,9 @@ if (!$success) {
 }
 
 header("Content-type: image/jpeg");
-header('Expires: ' . date('r',time() + 864000));
+header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+10 days")), true);
 header("Pragma: public");
 header("Cache-Control: public");
 header("Content-Length: " . strlen($contents));
-header("ETag: $etag");
+header("ETag: \"$etag\"");
 echo $contents;
diff --git a/mod/profile/icondirect.php b/mod/profile/icondirect.php
index c4439f78c..dbab5d31f 100644
--- a/mod/profile/icondirect.php
+++ b/mod/profile/icondirect.php
@@ -23,7 +23,7 @@ $guid = (int)$_GET['guid'];
 
 // If is the same ETag, content didn't changed.
 $etag = $last_cache . $guid;
-if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == $etag) {
+if (isset($_SERVER['HTTP_IF_NONE_MATCH']) && trim($_SERVER['HTTP_IF_NONE_MATCH']) == "\"$etag\"") {
 	header("HTTP/1.1 304 Not Modified");
 	exit;
 }
@@ -55,19 +55,15 @@ if ($mysql_dblink) {
 			$user_path = date('Y/m/d/', $join_date) . $guid;
 
 			$filename = "$data_root$user_path/profile/{$guid}{$size}.jpg";
-			$contents = @file_get_contents($filename);
-			if (!empty($contents)) {
+			$size = @filesize($filename);
+			if ($size) {
 				header("Content-type: image/jpeg");
-				header('Expires: ' . date('r', strtotime("+6 months")), true);
+				header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+6 months")), true);
 				header("Pragma: public");
 				header("Cache-Control: public");
-				header("Content-Length: " . strlen($contents));
-				header("ETag: $etag");
-				// this chunking is done for supposedly better performance
-				$split_string = str_split($contents, 1024);
-				foreach ($split_string as $chunk) {
-					echo $chunk;
-				}
+				header("Content-Length: $size");
+				header("ETag: \"$etag\"");
+				readfile($filename);
 				exit;
 			}
 		}
diff --git a/pages/avatar/view.php b/pages/avatar/view.php
index bd6c95821..10d81fef1 100644
--- a/pages/avatar/view.php
+++ b/pages/avatar/view.php
@@ -46,7 +46,7 @@ if (!$success) {
 }
 
 header("Content-type: image/jpeg", true);
-header('Expires: ' . date('r', strtotime("+6 months")), true);
+header('Expires: ' . gmdate('D, d M Y H:i:s \G\M\T', strtotime("+6 months")), true);
 header("Pragma: public", true);
 header("Cache-Control: public", true);
 header("Content-Length: " . strlen($contents));