Enable double-submit CSRF protection

Author: nicolas-grekas

symfony/framework-bundle/7.2/config/packages/framework.yaml

@@ -1,6 +1,8 @@
 # see https://symfony.com/doc/current/reference/configuration/framework.html
 framework:
     secret: '%env(APP_SECRET)%'
+    form:
+        csrf_protection: x-csrf-token
 
     # Note that the session will be started ONLY if you read or write from it.
     session: true

symfony/stimulus-bundle/2.19/assets/bootstrap.js

@@ -0,0 +1,2 @@
+// register any custom, 3rd party controllers here
+// app.register('some_controller_name', SomeImportedController);

symfony/stimulus-bundle/2.19/assets/controllers.json

@@ -0,0 +1,4 @@
+{
+    "controllers": [],
+    "entrypoints": []
+}

symfony/stimulus-bundle/2.19/assets/controllers/csrf_protection_controller.js

@@ -0,0 +1,35 @@
+document.addEventListener('submit', function (event) {
+    let csrfField = event.target.querySelector('input[data-controller="csrf-protection"]');
+
+    if (!csrfField) {
+        return;
+    }
+
+    let csrfCookie = csrfField.getAttribute('data-csrf-protection-cookie');
+
+    if (!csrfCookie) {
+        csrfField.setAttribute('data-csrf-protection-cookie', csrfCookie = csrfField.value);
+    }
+
+
+    if (!/^[-a-zA-Z0-9_]+$/.test(csrfCookie)) {
+        return
+    }
+
+    let csrfToken = btoa(String.fromCharCode.apply(null, (window.crypto || window.msCrypto).getRandomValues(new Uint8Array(18))));
+    csrfField.value = csrfToken;
+    let cookie = csrfCookie + '_' + csrfToken + '=' + csrfCookie + '; path=/; samesite=strict';
+
+    document.cookie = window.location.protocol === 'https:' ? '__Host-' + cookie + '; secure' : cookie;
+});
+
+document.addEventListener('turbo:submit-start', function (event) {
+    let csrfField = event.detail.formSubmission.formElement.querySelector('input[data-controller="csrf-protection"]');
+
+    if (csrfField) {
+        event.detail.formSubmission.fetchRequest.headers[csrfField.getAttribute('data-csrf-protection-cookie')] = csrfField.value;
+    }
+});
+
+/* stimulusFetch: 'lazy' */
+export default 'csrf-protection-controller';

symfony/stimulus-bundle/2.19/assets/controllers/hello_controller.js

@@ -0,0 +1,16 @@
+import { Controller } from '@hotwired/stimulus';
+
+/*
+ * This is an example Stimulus controller!
+ *
+ * Any element with a data-controller="hello" attribute will cause
+ * this controller to be executed. The name "hello" comes from the filename:
+ * hello_controller.js -> "hello"
+ *
+ * Delete this file or adapt it for your use!
+ */
+export default class extends Controller {
+    connect() {
+        this.element.textContent = 'Hello Stimulus! Edit me in assets/controllers/hello_controller.js';
+    }
+}

symfony/stimulus-bundle/2.19/manifest.json

@@ -0,0 +1,41 @@
+{
+    "bundles": {
+        "Symfony\\UX\\StimulusBundle\\StimulusBundle": ["all"]
+    },
+    "copy-from-recipe": {
+        "assets/": "assets/"
+    },
+    "aliases": ["stimulus", "stimulus-bundle"],
+    "conflict": {
+        "symfony/framework-bundle": "<7.2",
+        "symfony/security-csrf": "<7.2",
+        "symfony/webpack-encore-bundle": "<2.0",
+        "symfony/flex": "<1.20.0 || >=2.0.0,<2.3.0"
+    },
+    "add-lines": [
+        {
+            "file": "webpack.config.js",
+            "content": "\n    // enables the Symfony UX Stimulus bridge (used in assets/bootstrap.js)\n    .enableStimulusBridge('./assets/controllers.json')",
+            "position": "after_target",
+            "target": ".splitEntryChunks()"
+        },
+        {
+            "file": "assets/app.js",
+            "content": "import './bootstrap.js';",
+            "position": "top",
+            "warn_if_missing": true
+        },
+        {
+            "file": "assets/bootstrap.js",
+            "content": "import { startStimulusApp } from '@symfony/stimulus-bridge';\n\n// Registers Stimulus controllers from controllers.json and in the controllers/ directory\nexport const app = startStimulusApp(require.context(\n    '@symfony/stimulus-bridge/lazy-controller-loader!./controllers',\n    true,\n    /\\.[jt]sx?$/\n));",
+            "position": "top",
+            "requires": "symfony/webpack-encore-bundle"
+        },
+        {
+            "file": "assets/bootstrap.js",
+            "content": "import { startStimulusApp } from '@symfony/stimulus-bundle';\n\nconst app = startStimulusApp();",
+            "position": "top",
+            "requires": "symfony/asset-mapper"
+        }
+    ]
+}