Ironrdp Activex Mstsc Testing

Native MSTSC ActiveX testing

Exercise this exact host path:

mstscex.exe -> mstsc.exe -> MsRdpEx.dll -> ironrdpax.dll

Read the native MSTSC, certificate, resize, and local RPC sections of crates\ironrdp-activex\README.md before testing. Treat that README and ironrdp-agent --help-agent as the current behavior contract.

Guardrails

• Use only an explicitly authorized endpoint and credentials.
• Load an architecture-matched target\release\ironrdpax.dll through MSRDPEX_MSTSCAX_DLL.
• Never register the test DLL, replace mstscax.dll, or alter machine-wide RDP settings.
• Keep credentials in the launcher process environment. Never print them or place them in commands, .rdp files, reports, traces, screenshots, or repository files.
• Keep scripts and artifacts in the session artifact directory.
• Do not synthesize pointer-bearing messages such as WM_DPICHANGED. Use UI Automation, SendInput, and Win32 window APIs to produce real UI and window events.
• Do not disable certificate validation by default. Follow the control's certificate-warning UI for an authorized endpoint. Set AuthenticationLevel=0 only when the user explicitly authorizes that weaker policy for an isolated test endpoint and the chosen host exposes a supported preconnect setter.

Launch and connect

1. Build with cargo build -p ironrdp-activex --release.

2. In one PowerShell process, set:

   $env:MSRDPEX_MSTSCAX_DLL = (Resolve-Path .\target\release\ironrdpax.dll)
   $env:MSRDPEX_AX_BACKEND = 'ironrdp'
   $env:IRONRDP_ACTIVEX_NATIVE_MSTSC_CREDENTIAL_BRIDGE = '1'
   $env:IRONRDP_ACTIVEX_HOST_TRACE = '<session-artifacts>\mstsc.trace'
   

   Set RDP_USERNAME and RDP_PASSWORD only for CredUI prefill or authorized auto logon. Add RDP_AUTOLOGON=1 only for an explicitly authorized unattended run. Add IRONRDP_ACTIVEX_RPC=1 when post-connect inspection through ironrdp-agent --backend active-x is useful.

3. Snapshot existing mstsc.exe processes, then start the architecture-matched mstscex.exe without /axhost. Poll every 250 ms for up to 15 seconds for exactly one new mstsc.exe child, identified by parent PID and creation time. Fail the launch if the timeout expires or pre-existing processes make the target ambiguous.

4. Target UI Automation at that child. Set the visible Computer field and invoke Connect. Approve CredUI for an interactive run, then handle any certificate warning according to the authorized test policy. Do not use the ActiveX RPC connect operation because it bypasses the native MSTSC bridge being tested.

5. Confirm the expected bridge route in the value-free trace:

   NativeMstscCredentialBridge::StartProgramBridgeEnabled
   NativeMstscCredentialBridge::StartProgramBridgeAttached
   

   An interactive run must also reach ActiveXCredentialPrompt::Prompt and ActiveXCredentialPrompt::CredentialsAccepted. An unattended run must instead reach NativeMstscCredentialBridge::AutoLogon. Do not require username-form, certificate, clipboard, resize, or redraw markers when the corresponding feature or condition was not exercised.

Exercise and assess

Wait for a connected state and a rendered frame before stress testing. When RPC is enabled, use ironrdp-agent --backend active-x status and ironrdp-agent --backend active-x screenshot <session-artifacts>\frame.png.

Apply a bounded sequence of moves, valid resizes, minimize/restore, maximize/restore, hide/show, activation, invalidation, safe pointer input, wheel input, and a harmless key press such as VK_F24. Exercise SmartSizing or Zoom only when the native UI exposes it. Space resize changes by at least 250 ms.

After every case, require:

• The selected mstsc.exe PID is alive.
• IsWindow is true and IsHungAppWindow is false.
• SendMessageTimeout(WM_NULL, SMTO_ABORTIFHUNG, 500 ms) succeeds.
• GetWindowRect reports positive dimensions after restoring the window.
• The session remains connected unless the case intentionally disconnects it.

For resize coverage, accept an in-session display update or a bounded reconnect fallback. A RdpWorker::DisplayResizeFallback:* marker is diagnostic, not a failure, unless the session stays disconnected or the host becomes unresponsive. Fail on a connection failure, fatal event, unexpected disconnect, process exit, hung window, or missing rendered frame.

Teardown and report

Close the native shell through its UI and accept the standard disconnect confirmation. Poll every 250 ms for up to 10 seconds for the selected child and launcher PIDs to exit. If either remains, stop only those known PIDs and fail the teardown. Require IConnectionPoint::Unadvise in the trace, clear the process-local environment variables, and report only aggregate case results, liveness, value-free markers, and non-sensitive artifact paths.