fix: support macOS VNC connections (#1311)

src/backend/tests/hosts/guacamole/macos-vnc-proxy.test.ts

@@ -0,0 +1,80 @@
+import net from "net";
+import { afterEach, describe, expect, it } from "vitest";
+import { createMacosVncCompatibilityProxy } from "../../../hosts/guacamole/macos-vnc-proxy.js";
+
+const closers: Array<() => void> = [];
+
+afterEach(() => {
+  for (const close of closers.splice(0)) close();
+});
+
+async function listen(server: net.Server): Promise<number> {
+  return new Promise((resolve, reject) => {
+    server.once("error", reject);
+    server.listen(0, "127.0.0.1", () => {
+      resolve((server.address() as net.AddressInfo).port);
+    });
+  });
+}
+
+async function read(socket: net.Socket, length: number): Promise<Buffer> {
+  return new Promise((resolve, reject) => {
+    let received = Buffer.alloc(0);
+    const onData = (chunk: Buffer) => {
+      received = Buffer.concat([received, chunk]);
+      if (received.length < length) return;
+      socket.off("data", onData);
+      resolve(received);
+    };
+    socket.on("data", onData);
+    socket.once("error", reject);
+  });
+}
+
+describe("createMacosVncCompatibilityProxy", () => {
+  it("normalizes Apple's private RFB banner and preserves later traffic", async () => {
+    let clientBanner = "";
+    const target = net.createServer((socket) => {
+      socket.write("RFB 003.");
+      socket.write("889\n");
+      socket.once("data", (data) => {
+        clientBanner = data.toString("ascii");
+        socket.write("security-types");
+      });
+    });
+    const targetPort = await listen(target);
+    closers.push(() => target.close());
+
+    const proxy = await createMacosVncCompatibilityProxy({
+      targetHost: "127.0.0.1",
+      targetPort,
+      bindHost: "127.0.0.1",
+    });
+    closers.push(proxy.close);
+
+    const client = net.createConnection(proxy.port, "127.0.0.1");
+    closers.push(() => client.destroy());
+    expect((await read(client, 12)).subarray(0, 12).toString("ascii")).toBe(
+      "RFB 003.008\n",
+    );
+    client.write("RFB 003.008\n");
+    expect((await read(client, 14)).toString("ascii")).toBe("security-types");
+    expect(clientBanner).toBe("RFB 003.008\n");
+  });
+
+  it("passes standard RFB banners through unchanged", async () => {
+    const target = net.createServer((socket) => socket.write("RFB 003.008\n"));
+    const targetPort = await listen(target);
+    closers.push(() => target.close());
+    const proxy = await createMacosVncCompatibilityProxy({
+      targetHost: "127.0.0.1",
+      targetPort,
+      bindHost: "127.0.0.1",
+    });
+    closers.push(proxy.close);
+
+    const client = net.createConnection(proxy.port, "127.0.0.1");
+    closers.push(() => client.destroy());
+    expect((await read(client, 12)).toString("ascii")).toBe("RFB 003.008\n");
+  });
+});