Merge pull request github#3098 from kyprizel/master

Experimental SockJS support

Author: asgerf

javascript/ql/src/experimental/SockJS/SockJS.qll

@@ -0,0 +1,46 @@
+/**
+ * Provides classes for working with [SockJS](http://sockjs.org).
+ */
+
+import javascript
+
+/**
+ * A model of the `SockJS` websocket data handler (https://sockjs.org).
+ */
+module SockJS {
+  /**
+   * Access to user-controlled data object received from websocket
+   * For example:
+   * ```
+   * server.on('connection', function(conn) {
+   *     conn.on('data', function(message) {
+   *       ...
+   *     });
+   *  });
+   * ```
+   */
+  class SourceFromSocketJS extends RemoteFlowSource {
+    SourceFromSocketJS() {
+      exists(
+        DataFlow::CallNode createServer, DataFlow::CallNode connNode,
+        DataFlow::CallNode dataHandlerNode
+      |
+        createServer = appCreation() and
+        connNode = createServer.getAMethodCall("on") and
+        connNode.getArgument(0).getStringValue() = "connection" and
+        dataHandlerNode = connNode.getCallback(1).getParameter(0).getAMethodCall("on") and
+        dataHandlerNode.getArgument(0).getStringValue() = "data" and
+        this = dataHandlerNode.getCallback(1).getParameter(0)
+      )
+    }
+
+    override string getSourceType() { result = "input from SockJS WebSocket" }
+  }
+
+  /**
+   * Gets a new SockJS server.
+   */
+  private DataFlow::CallNode appCreation() {
+    result = DataFlow::moduleImport("sockjs").getAMemberCall("createServer")
+  }
+}

javascript/ql/src/experimental/SockJS/examples/server.js

@@ -0,0 +1,16 @@
+const express = require('express');
+const http = require('http');
+const sockjs = require('sockjs');
+
+const app = express();
+const server = http.createServer(app);
+const sockjs_echo = sockjs.createServer({});
+sockjs_echo.on('connection', function(conn) {
+    conn.on('data', function(message) {
+        var data = JSON.parse(message);
+        conn.write(JSON.stringify(eval(data.test)));
+    });
+});
+
+sockjs_echo.installHandlers(server, {prefix:'/echo'});
+server.listen(9090, '127.0.0.1');