fix(gateway): allow trusted-proxy control-ui auth to skip device pairing

Control UI connections authenticated via gateway.auth.mode=trusted-proxy were
still forced through device pairing because pairing bypass only considered
shared token/password auth (sharedAuthOk). In trusted-proxy deployments,
this produced persistent "pairing required" failures despite valid trusted
proxy headers.

Treat authenticated trusted-proxy control-ui connections as pairing-bypass
eligible and allow missing device identity in that mode.

Fixes #25293

Co-authored-by: Cursor <cursoragent@cursor.com>

src/gateway/server/ws-connection/connect-policy.test.ts

@@ -49,6 +49,7 @@ describe("ws connect policy", () => {
         role: "node",
         isControlUi: false,
         controlUiAuthPolicy: policy,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
@@ -68,6 +69,7 @@ describe("ws connect policy", () => {
         role: "operator",
         isControlUi: true,
         controlUiAuthPolicy: controlUiStrict,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
@@ -82,6 +84,7 @@ describe("ws connect policy", () => {
         role: "operator",
         isControlUi: true,
         controlUiAuthPolicy: controlUiStrict,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
@@ -101,6 +104,7 @@ describe("ws connect policy", () => {
         role: "operator",
         isControlUi: true,
         controlUiAuthPolicy: controlUiNoInsecure,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
@@ -114,6 +118,7 @@ describe("ws connect policy", () => {
         role: "operator",
         isControlUi: false,
         controlUiAuthPolicy: policy,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
@@ -127,6 +132,7 @@ describe("ws connect policy", () => {
         role: "operator",
         isControlUi: false,
         controlUiAuthPolicy: policy,
+        trustedProxyAuthOk: false,
         sharedAuthOk: false,
         authOk: false,
         hasSharedAuth: true,
@@ -140,15 +146,31 @@ describe("ws connect policy", () => {
         role: "node",
         isControlUi: false,
         controlUiAuthPolicy: policy,
+        trustedProxyAuthOk: false,
         sharedAuthOk: true,
         authOk: true,
         hasSharedAuth: true,
         isLocalClient: false,
       }).kind,
     ).toBe("reject-device-required");
+
+    // Trusted-proxy authenticated Control UI should bypass device-identity gating.
+    expect(
+      evaluateMissingDeviceIdentity({
+        hasDeviceIdentity: false,
+        role: "operator",
+        isControlUi: true,
+        controlUiAuthPolicy: controlUiNoInsecure,
+        trustedProxyAuthOk: true,
+        sharedAuthOk: false,
+        authOk: true,
+        hasSharedAuth: false,
+        isLocalClient: false,
+      }).kind,
+    ).toBe("allow");
   });
 
-  test("pairing bypass requires control-ui bypass + shared auth", () => {
+  test("pairing bypass requires control-ui bypass + shared auth (or trusted-proxy auth)", () => {
     const bypass = resolveControlUiAuthPolicy({
       isControlUi: true,
       controlUiConfig: { dangerouslyDisableDeviceAuth: true },
@@ -159,8 +181,9 @@ describe("ws connect policy", () => {
       controlUiConfig: undefined,
       deviceRaw: null,
     });
-    expect(shouldSkipControlUiPairing(bypass, true)).toBe(true);
-    expect(shouldSkipControlUiPairing(bypass, false)).toBe(false);
-    expect(shouldSkipControlUiPairing(strict, true)).toBe(false);
+    expect(shouldSkipControlUiPairing(bypass, true, false)).toBe(true);
+    expect(shouldSkipControlUiPairing(bypass, false, false)).toBe(false);
+    expect(shouldSkipControlUiPairing(strict, true, false)).toBe(false);
+    expect(shouldSkipControlUiPairing(strict, false, true)).toBe(true);
   });
 });

src/gateway/server/ws-connection/connect-policy.ts

@@ -35,7 +35,11 @@ export function resolveControlUiAuthPolicy(params: {
 export function shouldSkipControlUiPairing(
   policy: ControlUiAuthPolicy,
   sharedAuthOk: boolean,
+  trustedProxyAuthOk = false,
 ): boolean {
+  if (trustedProxyAuthOk) {
+    return true;
+  }
   return policy.allowBypass && sharedAuthOk;
 }
 
@@ -50,6 +54,7 @@ export function evaluateMissingDeviceIdentity(params: {
   role: GatewayRole;
   isControlUi: boolean;
   controlUiAuthPolicy: ControlUiAuthPolicy;
+  trustedProxyAuthOk?: boolean;
   sharedAuthOk: boolean;
   authOk: boolean;
   hasSharedAuth: boolean;
@@ -58,6 +63,9 @@ export function evaluateMissingDeviceIdentity(params: {
   if (params.hasDeviceIdentity) {
     return { kind: "allow" };
   }
+  if (params.isControlUi && params.trustedProxyAuthOk) {
+    return { kind: "allow" };
+  }
   if (params.isControlUi && !params.controlUiAuthPolicy.allowBypass) {
     // Allow localhost Control UI connections when allowInsecureAuth is configured.
     // Localhost has no network interception risk, and browser SubtleCrypto

src/gateway/server/ws-connection/message-handler.ts

@@ -427,11 +427,17 @@ export function attachGatewayWsMessageHandler(params: {
           if (!device) {
             clearUnboundScopes();
           }
+          const trustedProxyAuthOk =
+            isControlUi &&
+            resolvedAuth.mode === "trusted-proxy" &&
+            authOk &&
+            authMethod === "trusted-proxy";
           const decision = evaluateMissingDeviceIdentity({
             hasDeviceIdentity: Boolean(device),
             role,
             isControlUi,
             controlUiAuthPolicy,
+            trustedProxyAuthOk,
             sharedAuthOk,
             authOk,
             hasSharedAuth,
@@ -563,8 +569,13 @@ export function attachGatewayWsMessageHandler(params: {
         // In that case, don't force device pairing on first connect.
         const skipPairingForOperatorSharedAuth =
           role === "operator" && sharedAuthOk && !isControlUi && !isWebchat;
+        const trustedProxyAuthOk =
+          isControlUi &&
+          resolvedAuth.mode === "trusted-proxy" &&
+          authOk &&
+          authMethod === "trusted-proxy";
         const skipPairing =
-          shouldSkipControlUiPairing(controlUiAuthPolicy, sharedAuthOk) ||
+          shouldSkipControlUiPairing(controlUiAuthPolicy, sharedAuthOk, trustedProxyAuthOk) ||
           skipPairingForOperatorSharedAuth;
         if (device && devicePublicKey && !skipPairing) {
           const formatAuditList = (items: string[] | undefined): string => {