fix(proxy): cap connect tunnel timeouts

src/infra/net/http-connect-tunnel.test.ts

@@ -1,5 +1,6 @@
 import { EventEmitter } from "node:events";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
+import { MAX_TIMER_TIMEOUT_MS } from "../../shared/number-coercion.js";
 
 class FakeSocket extends EventEmitter {
   public readonly writes: string[] = [];
@@ -349,4 +350,27 @@ describe("openHttpConnectTunnel", () => {
     await rejected;
     expect(proxySocket.destroyed).toBe(true);
   });
+
+  it("caps oversized CONNECT timeouts before arming the watchdog", async () => {
+    vi.useFakeTimers();
+    const proxySocket = new FakeSocket();
+    setNextNetSocket(proxySocket);
+    const { openHttpConnectTunnel } = await import("./http-connect-tunnel.js");
+
+    const tunnel = openHttpConnectTunnel({
+      proxyUrl: new URL("http://proxy.example:8080"),
+      targetHost: "api.push.apple.com",
+      targetPort: 443,
+      timeoutMs: Number.MAX_SAFE_INTEGER,
+    });
+
+    await vi.advanceTimersByTimeAsync(1);
+    expect(proxySocket.destroyed).toBe(false);
+
+    await vi.advanceTimersByTimeAsync(MAX_TIMER_TIMEOUT_MS - 1);
+    await expect(tunnel).rejects.toThrow(
+      `Proxy CONNECT failed via http://proxy.example:8080: Proxy CONNECT timed out after ${MAX_TIMER_TIMEOUT_MS}ms`,
+    );
+    expect(proxySocket.destroyed).toBe(true);
+  });
 });

src/infra/net/http-connect-tunnel.ts

@@ -1,5 +1,6 @@
 import * as net from "node:net";
 import * as tls from "node:tls";
+import { resolveTimerTimeoutMs } from "../../shared/number-coercion.js";
 import type { ManagedProxyTlsOptions } from "./proxy/proxy-tls.js";
 
 export type HttpConnectTunnelParams = {
@@ -11,6 +12,7 @@ export type HttpConnectTunnelParams = {
 };
 
 const MAX_CONNECT_RESPONSE_HEADER_BYTES = 16 * 1024;
+const MIN_CONNECT_TIMEOUT_MS = 1;
 
 type ProxySocket = net.Socket | tls.TLSSocket;
 type ConnectResponseBuffer = Buffer;
@@ -159,11 +161,14 @@ class HttpConnectTunnelAttempt {
   }
 
   private startTimeout(): void {
-    const timeoutMs = this.params.timeoutMs;
-    if (timeoutMs && Number.isFinite(timeoutMs) && timeoutMs > 0) {
+    const timeoutMs =
+      this.params.timeoutMs === undefined || this.params.timeoutMs <= 0
+        ? undefined
+        : resolveTimerTimeoutMs(this.params.timeoutMs, MIN_CONNECT_TIMEOUT_MS);
+    if (timeoutMs !== undefined) {
       this.timeout = setTimeout(() => {
-        this.fail(new Error(`Proxy CONNECT timed out after ${Math.trunc(timeoutMs)}ms`));
-      }, Math.trunc(timeoutMs));
+        this.fail(new Error(`Proxy CONNECT timed out after ${timeoutMs}ms`));
+      }, timeoutMs);
     }
   }