- backend: require CSRF token to be passed via POST

- do not leak CSRF token via GET request in feed debugger
- rework Article/redirect to use POST

backend.php

@@ -20,7 +20,7 @@
 		return;
 	}
 
-	@$csrf_token = $_REQUEST['csrf_token'];
+	@$csrf_token = $_POST['csrf_token'];
 
 	require_once "autoload.php";
 	require_once "sessions.php";

classes/feeds.php

@@ -751,7 +751,7 @@ class Feeds extends Handler_Protected {
 
 		$feed_id = (int)$_REQUEST["feed_id"];
 		@$do_update = $_REQUEST["action"] == "do_update";
-		$csrf_token = $_REQUEST["csrf_token"];
+		$csrf_token = $_POST["csrf_token"];
 
 		$sth = $this->pdo->prepare("SELECT id FROM ttrss_feeds WHERE id = ? AND owner_uid = ?");
 		$sth->execute([$feed_id, $_SESSION['uid']]);
@@ -799,7 +799,7 @@ class Feeds extends Handler_Protected {
 			<div class="container">
 				<h1>Feed Debugger: <?php echo "$feed_id: " . $this->getFeedTitle($feed_id) ?></h1>
 				<div class="content">
-					<form method="GET" action="">
+					<form method="post" action="">
 						<input type="hidden" name="op" value="feeds">
 						<input type="hidden" name="method" value="update_debugger">
 						<input type="hidden" name="xdebug" value="1">

classes/handler/public.php

@@ -728,7 +728,7 @@ class Handler_Public extends Handler {
 		if ($_SESSION["uid"]) {
 
 			$feed_url = trim(clean($_REQUEST["feed_url"]));
-			$csrf_token = clean($_REQUEST["csrf_token"]);
+			$csrf_token = clean($_POST["csrf_token"]);
 
 			header('Content-Type: text/html; charset=utf-8');
 			?>

js/App.js

@@ -126,6 +126,32 @@ const App = {
 				return callOriginal(options);
 			}
 		);
+   },
+   postOpenWindow: function(target, params) {
+      const w = window.open("");
+
+		if (w) {
+			w.opener = null;
+
+			const form = document.createElement("form");
+
+			form.setAttribute("method", "post");
+			form.setAttribute("action", App.getInitParam("self_url_prefix") + "/" + target);
+
+			for (const [k,v] of Object.entries(params)) {
+				const field = document.createElement("input");
+
+				field.setAttribute("name", k);
+				field.setAttribute("value", v);
+				field.setAttribute("type", "hidden");
+
+				form.appendChild(field);
+			}
+
+			w.document.body.appendChild(form);
+			form.submit();
+		}
+
    },
 	urlParam: function(param) {
 		return String(window.location.href).parseQuery()[param];
@@ -986,8 +1012,11 @@ const App = {
          };
          this.hotkey_actions["feed_debug_update"] = () => {
             if (!Feeds.activeIsCat() && parseInt(Feeds.getActive()) > 0) {
-               window.open("backend.php?op=feeds&method=update_debugger&feed_id=" + Feeds.getActive() +
+               //window.open("backend.php?op=feeds&method=update_debugger&feed_id=" + Feeds.getActive());
-                  "&csrf_token=" + this.getInitParam("csrf_token"));
+
+               /* global __csrf_token */
+               App.postOpenWindow("backend.php", {op: "feeds", method: "update_debugger", feed_id: Feeds.getActive(), csrf_token: __csrf_token});
+
             } else {
                alert("You can't debug this kind of feed.");
             }

js/Article.js

@@ -131,37 +131,11 @@ const Article = {
 		});
 	},
 	openInNewWindow: function (id) {
-
-		const w = window.open("");
-
-		if (w) {
-			w.opener = null;
-
-			const form = document.createElement("form");
-
-			form.setAttribute("method", "post");
-			form.setAttribute("action", App.getInitParam("self_url_prefix") + "/backend.php");
-
 		/* global __csrf_token */
-
+		App.postOpenWindow("backend.php",
-			const params = { "op": "article", "method": "redirect", "id": id, "csrf_token": __csrf_token };
+			{ "op": "article", "method": "redirect", "id": id, "csrf_token": __csrf_token });
-
-			for (const [k,v] of Object.entries(params)) {
-				const field = document.createElement("input");
-
-				field.setAttribute("name", k);
-				field.setAttribute("value", v);
-				field.setAttribute("type", "hidden");
-
-				form.appendChild(field);
-			}
-
-			w.document.body.appendChild(form);
-			form.submit();
 
 		Headlines.toggleUnread(id, 0);
-		}
-
 	},
 	render: function (article) {
 		App.cleanupMemory("content-insert");

js/FeedTree.js

@@ -101,8 +101,9 @@ define(["dojo/_base/declare", "dojo/dom-construct", "dojo/_base/array", "dojo/co
 					menu.addChild(new dijit.MenuItem({
 						label: __("Debug feed"),
 						onClick: function() {
-							window.open("backend.php?op=feeds&method=update_debugger&feed_id=" + this.getParent().row_id +
+							/* global __csrf_token */
-								"&csrf_token=" + App.getInitParam("csrf_token"));
+							App.postOpenWindow("backend.php", {op: "feeds", method: "update_debugger",
+								feed_id: this.getParent().row_id, csrf_token: __csrf_token});
 						}}));
 				}