Merge pull request #997 from asger-semmle/closure-promise

JS: model of closure Promises

Author: Max Schaefer

javascript/ql/src/semmle/javascript/Promises.qll

@@ -45,3 +45,57 @@ module Q {
     override DataFlow::FunctionNode getExecutor() { result = getCallback(0) }
   }
 }
+
+private module ClosurePromise {
+  /**
+   * A promise created by a call `new goog.Promise(executor)`.
+   */
+  private class ClosurePromiseDefinition extends PromiseDefinition, DataFlow::NewNode {
+    ClosurePromiseDefinition() { this = Closure::moduleImport("goog.Promise").getACall() }
+
+    override DataFlow::FunctionNode getExecutor() { result = getCallback(0) }
+  }
+
+  /**
+   * A promise created by a call `goog.Promise.resolve(value)`.
+   */
+  private class ResolvedClosurePromiseDefinition extends ResolvedPromiseDefinition {
+    ResolvedClosurePromiseDefinition() {
+      this = Closure::moduleImport("goog.Promise.resolve").getACall()
+    }
+
+    override DataFlow::Node getValue() { result = getArgument(0) }
+  }
+
+  /**
+   * Taint steps through closure promise methods.
+   */
+  private class ClosurePromiseTaintStep extends TaintTracking::AdditionalTaintStep {
+    DataFlow::Node pred;
+
+    ClosurePromiseTaintStep() {
+      // static methods in goog.Promise
+      exists (DataFlow::CallNode call, string name |
+        call = Closure::moduleImport("goog.Promise." + name).getACall() and
+        this = call and
+        pred = call.getAnArgument()
+        |
+        name = "all" or
+        name = "allSettled" or
+        name = "firstFulfilled" or
+        name = "race"
+      )
+      or
+      // promise created through goog.promise.withResolver()
+      exists (DataFlow::CallNode resolver |
+        resolver = Closure::moduleImport("goog.Promise.withResolver").getACall() and
+        this = resolver.getAPropertyRead("promise") and
+        pred = resolver.getAMethodCall("resolve").getArgument(0)
+      )
+    }
+
+    override predicate step(DataFlow::Node src, DataFlow::Node dst) {
+      src = pred and dst = this
+    }
+  }
+}

javascript/ql/test/library-tests/Promises/AdditionalPromises.expected

@@ -5,3 +5,5 @@
 | promises.js:43:19:45:6 | Q.Promi ... \\n    }) |
 | promises.js:53:19:53:41 | Promise ... source) |
 | promises.js:62:19:62:41 | Promise ... source) |
+| promises.js:71:5:71:27 | Promise ... source) |
+| promises.js:72:5:72:41 | new Pro ... ource)) |

javascript/ql/test/library-tests/Promises/ResolvedPromiseDefinition.expected

@@ -1,2 +1,3 @@
 | promises.js:53:19:53:41 | Promise ... source) | promises.js:53:35:53:40 | source |
 | promises.js:62:19:62:41 | Promise ... source) | promises.js:62:35:62:40 | source |
+| promises.js:71:5:71:27 | Promise ... source) | promises.js:71:21:71:26 | source |

javascript/ql/test/library-tests/Promises/promises.js

@@ -64,3 +64,13 @@
         var sink = val;
     });
 })();
+
+(function() {
+    var Promise = goog.require('goog.Promise');
+    var source = "tainted";
+    Promise.resolve(source).then(val => { var sink = val; });
+    new Promise((res,rej) => res(source)).then(val => { var sink = val });
+    let resolver = Promise.withResolver();
+    resolver.resolve(source);
+    resolver.promise.then(val => { var sink = val });
+})();

javascript/ql/test/library-tests/TaintTracking/BasicTaintTracking.expected

@@ -26,6 +26,8 @@
 | partialCalls.js:4:17:4:24 | source() | partialCalls.js:51:14:51:14 | x |
 | promise.js:4:24:4:31 | source() | promise.js:4:8:4:32 | Promise ... urce()) |
 | promise.js:5:25:5:32 | source() | promise.js:5:8:5:33 | bluebir ... urce()) |
+| promise.js:10:24:10:31 | source() | promise.js:10:8:10:32 | Promise ... urce()) |
+| promise.js:12:20:12:27 | source() | promise.js:13:8:13:23 | resolver.promise |
 | sanitizer-guards.js:2:11:2:18 | source() | sanitizer-guards.js:4:8:4:8 | x |
 | sanitizer-guards.js:13:14:13:21 | source() | sanitizer-guards.js:15:10:15:15 | this.x |
 | sanitizer-guards.js:13:14:13:21 | source() | sanitizer-guards.js:21:14:21:19 | this.x |

javascript/ql/test/library-tests/TaintTracking/promise.js

@@ -4,3 +4,11 @@ function test() {
   sink(Promise.resolve(source())); // NOT OK
   sink(bluebird.resolve(source())); // NOT OK
 }
+
+function closure() {
+  let Promise = goog.require('goog.Promise');
+  sink(Promise.resolve(source())); // NOT OK
+  let resolver = Promise.withResolver();
+  resolver.resolve(source());
+  sink(resolver.promise); // NOT OK
+}