Merge branch 'dev' into beta

1 files changed, 14 insertions, 0 deletions

diff --git a/lib/lib_rss.php b/lib/lib_rss.php
index 823f53716..31c9cdbc1 100644
--- a/lib/lib_rss.php
+++ b/lib/lib_rss.php
@@ -230,3 +230,17 @@ function cryptAvailable() {
 	}
 	return false;
 }
+
+function is_referer_from_same_domain() {
+	if (empty($_SERVER['HTTP_REFERER'])) {
+		return false;
+	}
+	$host = parse_url(((isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] === 'on') ? 'https://' : 'http://') .
+		(empty($_SERVER['HTTP_HOST']) ? $_SERVER['SERVER_NAME'] : $_SERVER['HTTP_HOST']));
+	$referer = parse_url($_SERVER['HTTP_REFERER']);
+	if (empty($host['scheme']) || empty($referer['scheme']) || $host['scheme'] !== $referer['scheme'] ||
+	    empty($host['host']) || empty($referer['host']) || $host['host'] !== $referer['host']) {
+		return false;
+	}
+	return (isset($host['port']) ? $host['port'] : 0) === (isset($referer['port']) ? $referer['port'] : 0);
+}