Fix #70

MichaelXF · May 17, 2023 · d109f8b · d109f8b
1 parent 2f4202d
commit d109f8b
Show file tree

Hide file tree

Showing 2 changed files with 52 additions and 1 deletion.
diff --git a/src/transforms/controlFlowFlattening/controlFlowFlattening.ts b/src/transforms/controlFlowFlattening/controlFlowFlattening.ts
@@ -47,6 +47,7 @@ import ChoiceFlowObfuscation from "./choiceFlowObfuscation";
 import ControlFlowObfuscation from "./controlFlowObfuscation";
 import ExpressionObfuscation from "./expressionObfuscation";
 import SwitchCaseObfuscation from "./switchCaseObfuscation";
+import { isModuleSource } from "../string/stringConcealing";
 
 var flattenStructures = new Set([
   "IfStatement",
@@ -226,6 +227,13 @@ export default class ControlFlowFlattening extends Transform {
         fnNames.delete(illegal);
       });
 
+      var importDeclarations = [];
+      for (var stmt of body) {
+        if (stmt.type === "ImportDeclaration") {
+          importDeclarations.push(stmt);
+        }
+      }
+
       var fraction = 0.9;
       if (body.length > 20) {
         fraction /= Math.max(1.2, body.length - 18);
@@ -285,6 +293,7 @@ export default class ControlFlowFlattening extends Transform {
             if (
               o.type == "Literal" &&
               typeof o.value == "string" &&
+              !isModuleSource(o, p) &&
               !o.regex &&
               Math.random() / (Object.keys(stringBank).length / 2 + 1) > 0.5
             ) {
@@ -318,7 +327,10 @@ export default class ControlFlowFlattening extends Transform {
         };
 
         body.forEach((stmt, i) => {
-          if (functionDeclarations.has(stmt)) {
+          if (
+            functionDeclarations.has(stmt) ||
+            stmt.type === "ImportDeclaration"
+          ) {
             return;
           }
 
@@ -1045,6 +1057,9 @@ export default class ControlFlowFlattening extends Transform {
       var discriminant = Template(`${stateVars.join("+")}`).single().expression;
 
       body.length = 0;
+      for (var importDeclaration of importDeclarations) {
+        body.push(importDeclaration);
+      }
 
       if (functionDeclarations.size) {
         functionDeclarations.forEach((x) => {

diff --git a/test/transforms/controlFlowFlattening/controlFlowFlattening.test.ts b/test/transforms/controlFlowFlattening/controlFlowFlattening.test.ts
@@ -672,3 +672,39 @@ test("Variant #20: Don't apply when functions are redefined", async () => {
   eval(output);
   expect(TEST_ARRAY).toStrictEqual([0, 0, 0]);
 });
+
+// https://github.com/MichaelXF/js-confuser/issues/70
+test("Variant #21: Don't move Import Declarations", async () => {
+  var output = await JsConfuser(
+    `
+    import {createHash} from "crypto";
+    var inputString = "Hash this string";
+    var hashed = createHash("sha256").update(inputString).digest("hex");
+    TEST_OUTPUT = hashed;
+  `,
+    {
+      target: "node",
+      controlFlowFlattening: true,
+    }
+  );
+
+  // Ensure Control Flow FLattening was applied
+  expect(output).toContain("switch");
+
+  // Ensure the import declaration wasn't moved
+  expect(output.startsWith("import")).toStrictEqual(true);
+
+  // Convert to runnable code
+  output = output.replace(
+    `import{createHash}from'crypto';`,
+    "const {createHash}=require('crypto');"
+  );
+
+  var TEST_OUTPUT = "";
+
+  eval(output);
+
+  expect(TEST_OUTPUT).toStrictEqual(
+    "1cac63f39fd68d8c531f27b807610fb3d50f0fc3f186995767fb6316e7200a3e"
+  );
+});