feat(NODE-6333): Allow callers to specify the 'protect' flag (#198)

Co-authored-by: Michael Johns <michael.johns@apiture.com>
Co-authored-by: Bailey Pearson <bailey.pearson@mongodb.com>
Co-authored-by: Durran Jordan <durran@gmail.com>
Co-authored-by: Bailey Pearson <bailey.pearson@gmail.com>

README.md

@@ -182,6 +182,7 @@ Processes a single kerberos client-side step using the supplied server challenge
 | challenge | <code>string</code> | The response returned after calling `unwrap` |
 | [options] | <code>object</code> | Optional settings |
 | [options.user] | <code>string</code> | The user to authorize |
+| [options.protect] | <code>boolean</code> | Indicates if the wrap should request message confidentiality |
 | [callback] | <code>function</code> |  |
 
 Perform the client side kerberos wrap step.

lib/kerberos.js

@@ -52,6 +52,7 @@ KerberosClient.prototype.step = defineOperation(KerberosClient.prototype.step, [
  * @param {string} challenge The response returned after calling `unwrap`
  * @param {object} [options] Optional settings
  * @param {string} [options.user] The user to authorize
+ * @param {boolean} [options.protect] Indicates if the wrap should request message confidentiality
  * @param {function} [callback]
  * @return {Promise} returns Promise if no callback passed
  */

src/kerberos.cc

@@ -37,6 +37,17 @@ std::string ToStringWithNonStringAsEmpty(Napi::Value value) {
     return value.As<String>();
 }
 
+int KerberosClient::ParseWrapOptionsProtect(const Napi::Object& options) {
+    if (!options.Has("protect"))    return 0;
+
+    if (!options.Get("protect").IsBoolean()) {
+        throw TypeError::New(options.Env(), "options.protect must be a boolean.");
+    }
+
+    bool protect = options.Get("protect").As<Boolean>();
+    return protect ? 1 : 0;
+}
+
 Function KerberosClient::Init(Napi::Env env) {
     return
         DefineClass(env,

src/kerberos.h

@@ -55,6 +55,8 @@ class KerberosClient : public Napi::ObjectWrap<KerberosClient> {
     void UnwrapData(const Napi::CallbackInfo& info);
     void WrapData(const Napi::CallbackInfo& info);
 
+    int ParseWrapOptionsProtect(const Napi::Object& options);
+
    private:
     friend class Napi::ObjectWrap<KerberosClient>;
     explicit KerberosClient(const Napi::CallbackInfo& info);

src/unix/kerberos_unix.cc

@@ -74,8 +74,7 @@ void KerberosClient::WrapData(const CallbackInfo& info) {
     Object options = info[1].ToObject();
     Function callback = info[2].As<Function>();
     std::string user = ToStringWithNonStringAsEmpty(options["user"]);
-
-    int protect = 0; // NOTE: this should be an option
+    int protect = ParseWrapOptionsProtect(options);
 
     KerberosWorker::Run(callback, "kerberos:ClientWrap", [=](KerberosWorker::SetOnFinishedHandler onFinished) {
         gss_result result = authenticate_gss_client_wrap(

src/win32/kerberos_win32.cc

@@ -92,7 +92,7 @@ void KerberosClient::WrapData(const CallbackInfo& info) {
     Object options = info[1].ToObject();
     Function callback = info[2].As<Function>();
     std::string user = ToStringWithNonStringAsEmpty(options["user"]);
-    int protect = 0; // NOTE: this should be an option
+    int protect = ParseWrapOptionsProtect(options);
 
     if (isStringTooLong(user)) {
         throw Error::New(info.Env(), "User name is too long");

test/kerberos_tests.js

@@ -4,6 +4,7 @@ const request = require('request');
 const chai = require('chai');
 const expect = chai.expect;
 const os = require('os');
+const { test } = require('mocha');
 chai.use(require('chai-string'));
 
 // environment variables
@@ -122,4 +123,50 @@ describe('Kerberos', function () {
       });
     });
   });
+
+  describe('Client.wrap()', function () {
+    async function establishConext() {
+      const service = `HTTP@${hostname}`;
+      client = await kerberos.initializeClient(service, {});
+      server = await kerberos.initializeServer(service);
+      const clientResponse = await client.step('');
+      const serverResponse = await server.step(clientResponse);
+      await client.step(serverResponse);
+      expect(client.contextComplete).to.be.true;
+      return { client, server };
+    }
+
+    let client;
+    let server;
+
+    before(establishConext);
+    describe('options.protect', function () {
+      context('valid values for `protect`', function () {
+        test('no options provided', async function () {
+          await client.wrap('challenge');
+        });
+
+        test('options provided (protect omitted)', async function () {
+          await client.wrap('challenge', {});
+        });
+
+        test('protect = false', async function () {
+          await client.wrap('challenge', { protect: false });
+        });
+
+        test('protect = true', async function () {
+          await client.wrap('challenge', { protect: true });
+        });
+      });
+
+      context('when set to an invalid value', function () {
+        it('throws a TypeError', async function () {
+          const error = await client.wrap('challenge', { protect: 'non-boolean' }).catch(e => e);
+          expect(error)
+            .to.be.instanceOf(TypeError)
+            .to.match(/options.protect must be a boolean/);
+        });
+      });
+    });
+  });
 });