Files
mike f8ead215d8
build-windows / build-hello-agent-x64 (push) Successful in 5m41s
Initial commit: hello-agent — headless RustDesk-protocol-compatible Windows agent
A single-binary, Flutter-free remote-support agent that speaks the stock
RustDesk wire protocol. Designed for one-line MDM deployment against a
self-hosted rustdesk-server: a supporter using the unmodified rustdesk.exe
client connects, the controlled-side user gets a native Win32 approval
prompt, click Yes / No.

CLI surface

    hello-agent.exe --install                # register + start service
    hello-agent.exe --uninstall              # stop, delete, clean up
    hello-agent.exe --config <BLOB>          # admin-UI deploy string
    hello-agent.exe --install --config <BLOB>   # MDM one-liner

--config accepts both forms emitted by the rustdesk-server admin UI: the
reversed-base64 deploy string and the host=,key=,api=,relay= filename
form. Decoded via the upstream custom_server module, persisted via
hbb_common::config::Config::set_option.

Architecture

    --service runs as a Session 0 LocalSystem service. It polls
    WTSGetActiveConsoleSessionId and (re)spawns hello-agent.exe --server
    into the active console session via librustdesk::platform::run_as_user,
    handling the Session 0 → user-session token impersonation.

    --server is the worker. It boots three concurrent components:
      1. cm_popup: an IPC listener on the rustdesk `_cm` named pipe
      2. librustdesk::start_server(true, false): the upstream protocol
         stack — rendezvous mediator, NAT punch, IPC server, screen
         capture, login validation, hbbs_http heartbeat / sysinfo sync
      3. (implicit) ApproveMode::Click is pinned in config, so every
         incoming connection routes through cm_popup

The popup mechanism reuses an existing upstream contract without any
patches to the protocol code: when a peer connects with no password,
Connection::start in the upstream code calls try_start_cm_ipc, which
ipc::connect-s the `_cm` pipe before falling back to spawning a Flutter
CM child. Since cm_popup is up first, step 1 succeeds; we read the
Data::Login{authorized:false} frame, show MessageBoxTimeoutW (Yes/No,
60s, top-most, system-modal), and reply Data::Authorize or Data::Close.

Source tree

    src/main.rs             CLI dispatcher + run_server() composition
    src/cli.rs              hand-rolled argv parser + unit tests
    src/service.rs          windows-service install/uninstall/dispatcher
    src/config_import.rs    --config blob decoding + persistence
    src/cm_popup.rs         _cm IPC listener + Win32 approval dialog

Vendoring

The upstream RustDesk crate is vendored under vendor/rustdesk/ — full
workspace including libs/{hbb_common, scrap, enigo, clipboard,
virtual_display, remote_printer}. This makes the build self-contained
(no submodules, no sibling-repo checkout in CI) and gives us freedom to
fork in a different direction later. Excluded from the vendor: .git,
target/, flutter/, appimage/, flatpak/, fastlane/, docs/, examples/,
ci/, build.py, Dockerfile, upstream README/CLAUDE/AGENTS/GEMINI.

One local divergence vs. upstream: vendor/rustdesk/src/lib.rs flips
`mod custom_server` → `pub mod custom_server` so config_import.rs can
call get_custom_server_from_string without going through the
ui_interface shim. Documented in README.md → "Re-syncing the vendored
copy".

CI

.gitea/workflows/build-windows.yml builds on a self-hosted Windows
runner with Rust 1.75, LLVM 15.0.6 (libclang for bindgen via libvpx-sys),
and a vcpkg cache. The vendored vcpkg.json drives x64-windows-static
deps. The workflow stages the resulting hello-agent.exe into
SignOutput\, reports authenticode signing status (warns on unsigned),
and uploads as artifact. ~15 min full build, faster on incremental.

Out of scope for this commit: Linux/macOS builds, code signing, MSI
packaging, coexistence with stock rustdesk on the same box (currently
shares the RustDesk APP_NAME and config dir).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-08 16:29:31 +02:00

518 lines
18 KiB
C++

#include "pch.h"
#include <Windows.h>
#include <winspool.h>
#include <setupapi.h>
#include <memory>
#include <string>
#include <functional>
#include <vector>
#include <iostream>
#include "Common.h"
#pragma comment(lib, "setupapi.lib")
#pragma comment(lib, "winspool.lib")
namespace RemotePrinter
{
#define HRESULT_ERR_ELEMENT_NOT_FOUND 0x80070490
LPCWCH RD_DRIVER_INF_PATH = L"drivers\\RustDeskPrinterDriver\\RustDeskPrinterDriver.inf";
LPCWCH RD_PRINTER_PORT = L"RustDesk Printer";
LPCWCH RD_PRINTER_NAME = L"RustDesk Printer";
LPCWCH RD_PRINTER_DRIVER_NAME = L"RustDesk v4 Printer Driver";
LPCWCH XCV_MONITOR_LOCAL_PORT = L",XcvMonitor Local Port";
using FuncEnum = std::function<BOOL(DWORD level, LPBYTE pDriverInfo, DWORD cbBuf, LPDWORD pcbNeeded, LPDWORD pcReturned)>;
template <typename T, typename R>
using FuncOnData = std::function<std::shared_ptr<R>(const T &)>;
template <typename R>
using FuncOnNoData = std::function<std::shared_ptr<R>()>;
template <class T, class R>
std::shared_ptr<R> commonEnum(std::wstring funcName, FuncEnum func, DWORD level, FuncOnData<T, R> onData, FuncOnNoData<R> onNoData)
{
DWORD needed = 0;
DWORD returned = 0;
func(level, NULL, 0, &needed, &returned);
if (needed == 0)
{
return onNoData();
}
std::vector<BYTE> buffer(needed);
if (!func(level, buffer.data(), needed, &needed, &returned))
{
return nullptr;
}
T *pPortInfo = reinterpret_cast<T *>(buffer.data());
for (DWORD i = 0; i < returned; i++)
{
auto r = onData(pPortInfo[i]);
if (r)
{
return r;
}
}
return onNoData();
}
BOOL isNameEqual(LPCWSTR lhs, LPCWSTR rhs)
{
// https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-lstrcmpiw
// For some locales, the lstrcmpi function may be insufficient.
// If this occurs, use `CompareStringEx` to ensure proper comparison.
// For example, in Japan call with the NORM_IGNORECASE, NORM_IGNOREKANATYPE, and NORM_IGNOREWIDTH values to achieve the most appropriate non-exact string comparison.
// Note that specifying these values slows performance, so use them only when necessary.
//
// No need to consider `CompareStringEx` for now.
return lstrcmpiW(lhs, rhs) == 0 ? TRUE : FALSE;
}
BOOL enumPrinterPort(
DWORD level,
LPBYTE pPortInfo,
DWORD cbBuf,
LPDWORD pcbNeeded,
LPDWORD pcReturned)
{
// https://learn.microsoft.com/en-us/windows/win32/printdocs/enumports
// This is a blocking or synchronous function and might not return immediately.
// How quickly this function returns depends on run-time factors
// such as network status, print server configuration, and printer driver implementation factors that are difficult to predict when writing an application.
// Calling this function from a thread that manages interaction with the user interface could make the application appear to be unresponsive.
return EnumPortsW(NULL, level, pPortInfo, cbBuf, pcbNeeded, pcReturned);
}
BOOL isPortExists(LPCWSTR port)
{
auto onData = [port](const PORT_INFO_2 &info)
{
if (isNameEqual(info.pPortName, port) == TRUE) {
return std::shared_ptr<BOOL>(new BOOL(TRUE));
}
else {
return std::shared_ptr<BOOL>(nullptr);
} };
auto onNoData = []()
{ return nullptr; };
auto res = commonEnum<PORT_INFO_2, BOOL>(L"EnumPortsW", enumPrinterPort, 2, onData, onNoData);
if (res == nullptr)
{
return false;
}
else
{
return *res;
}
}
BOOL executeOnLocalPort(LPCWSTR port, LPCWSTR command)
{
PRINTER_DEFAULTSW dft = {0};
dft.DesiredAccess = SERVER_WRITE;
HANDLE hMonitor = NULL;
if (OpenPrinterW(const_cast<LPWSTR>(XCV_MONITOR_LOCAL_PORT), &hMonitor, &dft) == FALSE)
{
return FALSE;
}
DWORD outputNeeded = 0;
DWORD status = 0;
if (XcvDataW(hMonitor, command, (LPBYTE)port, (lstrlenW(port) + 1) * 2, NULL, 0, &outputNeeded, &status) == FALSE)
{
ClosePrinter(hMonitor);
return FALSE;
}
ClosePrinter(hMonitor);
return TRUE;
}
BOOL addLocalPort(LPCWSTR port)
{
return executeOnLocalPort(port, L"AddPort");
}
BOOL deleteLocalPort(LPCWSTR port)
{
return executeOnLocalPort(port, L"DeletePort");
}
BOOL checkAddLocalPort(LPCWSTR port)
{
if (!isPortExists(port))
{
return addLocalPort(port);
}
return TRUE;
}
std::wstring getPrinterInstalledOnPort(LPCWSTR port);
BOOL checkDeleteLocalPort(LPCWSTR port)
{
if (isPortExists(port))
{
if (getPrinterInstalledOnPort(port) != L"")
{
WcaLog(LOGMSG_STANDARD, "The printer is installed on the port. Please remove the printer first.\n");
return FALSE;
}
return deleteLocalPort(port);
}
return TRUE;
}
BOOL enumPrinterDriver(
DWORD level,
LPBYTE pDriverInfo,
DWORD cbBuf,
LPDWORD pcbNeeded,
LPDWORD pcReturned)
{
// https://learn.microsoft.com/en-us/windows/win32/printdocs/enumprinterdrivers
// This is a blocking or synchronous function and might not return immediately.
// How quickly this function returns depends on run-time factors
// such as network status, print server configuration, and printer driver implementation factors that are difficult to predict when writing an application.
// Calling this function from a thread that manages interaction with the user interface could make the application appear to be unresponsive.
return EnumPrinterDriversW(
NULL,
NULL,
level,
pDriverInfo,
cbBuf,
pcbNeeded,
pcReturned);
}
DWORDLONG getInstalledDriverVersion(LPCWSTR name)
{
auto onData = [name](const DRIVER_INFO_6W &info)
{
if (isNameEqual(name, info.pName) == TRUE)
{
return std::shared_ptr<DWORDLONG>(new DWORDLONG(info.dwlDriverVersion));
}
else
{
return std::shared_ptr<DWORDLONG>(nullptr);
} };
auto onNoData = []()
{ return nullptr; };
auto res = commonEnum<DRIVER_INFO_6W, DWORDLONG>(L"EnumPrinterDriversW", enumPrinterDriver, 6, onData, onNoData);
if (res == nullptr)
{
return 0;
}
else
{
return *res;
}
}
std::wstring findInf(LPCWSTR name)
{
auto onData = [name](const DRIVER_INFO_8W &info)
{
if (isNameEqual(name, info.pName) == TRUE)
{
return std::shared_ptr<std::wstring>(new std::wstring(info.pszInfPath));
}
else
{
return std::shared_ptr<std::wstring>(nullptr);
} };
auto onNoData = []()
{ return nullptr; };
auto res = commonEnum<DRIVER_INFO_8W, std::wstring>(L"EnumPrinterDriversW", enumPrinterDriver, 8, onData, onNoData);
if (res == nullptr)
{
return L"";
}
else
{
return *res;
}
}
BOOL deletePrinterDriver(LPCWSTR name)
{
// If the printer is used after the spooler service is started. E.g., printing a document through RustDesk Printer.
// `DeletePrinterDriverExW()` may fail with `ERROR_PRINTER_DRIVER_IN_USE`(3001, 0xBB9).
// We can only ignore this error for now.
// Though restarting the spooler service is a solution, it's not a good idea to restart the service.
//
// Deleting the printer driver after deleting the printer is a common practice.
// No idea why `DeletePrinterDriverExW()` fails with `ERROR_UNKNOWN_PRINTER_DRIVER` after using the printer once.
// https://github.com/ChromiumWebApps/chromium/blob/c7361d39be8abd1574e6ce8957c8dbddd4c6ccf7/cloud_print/virtual_driver/win/install/setup.cc#L422
// AnyDesk printer driver and the simplest printer driver also have the same issue.
BOOL res = DeletePrinterDriverExW(NULL, NULL, const_cast<LPWSTR>(name), DPD_DELETE_ALL_FILES, 0);
if (res == FALSE)
{
DWORD error = GetLastError();
if (error == ERROR_UNKNOWN_PRINTER_DRIVER)
{
return TRUE;
}
else
{
WcaLog(LOGMSG_STANDARD, "Failed to delete printer driver. Error (%d)\n", error);
}
}
return res;
}
BOOL deletePrinterDriverPackage(const std::wstring &inf)
{
// https://learn.microsoft.com/en-us/windows/win32/printdocs/deleteprinterdriverpackage
// This function is a blocking or synchronous function and might not return immediately.
// How quickly this function returns depends on run-time factors such as network status, print server configuration, and printer driver implementation factors that are difficult to predict when writing an application.
// Calling this function from a thread that manages interaction with the user interface could make the application appear to be unresponsive.
int tries = 3;
HRESULT result = S_FALSE;
while ((result = DeletePrinterDriverPackage(NULL, inf.c_str(), NULL)) != S_OK)
{
if (result == HRESULT_ERR_ELEMENT_NOT_FOUND)
{
return TRUE;
}
WcaLog(LOGMSG_STANDARD, "Failed to delete printer driver package. HRESULT (%d)\n", result);
tries--;
if (tries <= 0)
{
return FALSE;
}
Sleep(2000);
}
return S_OK;
}
BOOL uninstallDriver(LPCWSTR name)
{
auto infFile = findInf(name);
if (!deletePrinterDriver(name))
{
return FALSE;
}
if (infFile != L"" && !deletePrinterDriverPackage(infFile))
{
return FALSE;
}
return TRUE;
}
BOOL installDriver(LPCWSTR name, LPCWSTR inf)
{
DWORD size = MAX_PATH * 10;
wchar_t package_path[MAX_PATH * 10] = {0};
HRESULT result = UploadPrinterDriverPackage(
NULL, inf, NULL,
UPDP_SILENT_UPLOAD | UPDP_UPLOAD_ALWAYS, NULL, package_path, &size);
if (result != S_OK)
{
WcaLog(LOGMSG_STANDARD, "Uploading the printer driver package to the driver cache silently, failed. Will retry with user UI. HRESULT (%d)\n", result);
result = UploadPrinterDriverPackage(
NULL, inf, NULL, UPDP_UPLOAD_ALWAYS,
GetForegroundWindow(), package_path, &size);
if (result != S_OK)
{
WcaLog(LOGMSG_STANDARD, "Uploading the printer driver package to the driver cache failed with user UI. Aborting...\n");
return FALSE;
}
}
result = InstallPrinterDriverFromPackage(
NULL, package_path, name, NULL, IPDFP_COPY_ALL_FILES);
if (result != S_OK)
{
WcaLog(LOGMSG_STANDARD, "Installing the printer driver failed. HRESULT (%d)\n", result);
}
return result == S_OK;
}
BOOL enumLocalPrinter(
DWORD level,
LPBYTE pPrinterInfo,
DWORD cbBuf,
LPDWORD pcbNeeded,
LPDWORD pcReturned)
{
// https://learn.microsoft.com/en-us/windows/win32/printdocs/enumprinters
// This is a blocking or synchronous function and might not return immediately.
// How quickly this function returns depends on run-time factors
// such as network status, print server configuration, and printer driver implementation factors that are difficult to predict when writing an application.
// Calling this function from a thread that manages interaction with the user interface could make the application appear to be unresponsive.
return EnumPrintersW(PRINTER_ENUM_LOCAL, NULL, level, pPrinterInfo, cbBuf, pcbNeeded, pcReturned);
}
BOOL isPrinterAdded(LPCWSTR name)
{
auto onData = [name](const PRINTER_INFO_1W &info)
{
if (isNameEqual(name, info.pName) == TRUE)
{
return std::shared_ptr<BOOL>(new BOOL(TRUE));
}
else
{
return std::shared_ptr<BOOL>(nullptr);
} };
auto onNoData = []()
{ return nullptr; };
auto res = commonEnum<PRINTER_INFO_1W, BOOL>(L"EnumPrintersW", enumLocalPrinter, 1, onData, onNoData);
if (res == nullptr)
{
return FALSE;
}
else
{
return *res;
}
}
std::wstring getPrinterInstalledOnPort(LPCWSTR port)
{
auto onData = [port](const PRINTER_INFO_2W &info)
{
if (isNameEqual(port, info.pPortName) == TRUE)
{
return std::shared_ptr<std::wstring>(new std::wstring(info.pPrinterName));
}
else
{
return std::shared_ptr<std::wstring>(nullptr);
} };
auto onNoData = []()
{ return nullptr; };
auto res = commonEnum<PRINTER_INFO_2W, std::wstring>(L"EnumPrintersW", enumLocalPrinter, 2, onData, onNoData);
if (res == nullptr)
{
return L"";
}
else
{
return *res;
}
}
BOOL addPrinter(LPCWSTR name, LPCWSTR driver, LPCWSTR port)
{
PRINTER_INFO_2W printerInfo = {0};
printerInfo.pPrinterName = const_cast<LPWSTR>(name);
printerInfo.pPortName = const_cast<LPWSTR>(port);
printerInfo.pDriverName = const_cast<LPWSTR>(driver);
printerInfo.pPrintProcessor = const_cast<LPWSTR>(L"WinPrint");
printerInfo.pDatatype = const_cast<LPWSTR>(L"RAW");
printerInfo.Attributes = PRINTER_ATTRIBUTE_LOCAL;
HANDLE hPrinter = AddPrinterW(NULL, 2, (LPBYTE)&printerInfo);
return hPrinter == NULL ? FALSE : TRUE;
}
VOID deletePrinter(LPCWSTR name)
{
PRINTER_DEFAULTSW dft = {0};
dft.DesiredAccess = PRINTER_ALL_ACCESS;
HANDLE hPrinter = NULL;
if (OpenPrinterW(const_cast<LPWSTR>(name), &hPrinter, &dft) == FALSE)
{
DWORD error = GetLastError();
if (error == ERROR_INVALID_PRINTER_NAME)
{
return;
}
WcaLog(LOGMSG_STANDARD, "Failed to open printer. error (%d)\n", error);
return;
}
if (SetPrinterW(hPrinter, 0, NULL, PRINTER_CONTROL_PURGE) == FALSE)
{
ClosePrinter(hPrinter);
WcaLog(LOGMSG_STANDARD, "Failed to purge printer queue. error (%d)\n", GetLastError());
return;
}
if (DeletePrinter(hPrinter) == FALSE)
{
ClosePrinter(hPrinter);
WcaLog(LOGMSG_STANDARD, "Failed to delete printer. error (%d)\n", GetLastError());
return;
}
ClosePrinter(hPrinter);
}
bool FileExists(const std::wstring &filePath)
{
DWORD fileAttributes = GetFileAttributes(filePath.c_str());
return (fileAttributes != INVALID_FILE_ATTRIBUTES && !(fileAttributes & FILE_ATTRIBUTE_DIRECTORY));
}
// Steps:
// 1. Add the local port.
// 2. Check if the driver is installed.
// Uninstall the existing driver if it is installed.
// We should not check the driver version because the driver is deployed with the application.
// It's better to uninstall the existing driver and install the driver from the application.
// 3. Add the printer.
VOID installUpdatePrinter(const std::wstring &installFolder)
{
const std::wstring infFile = installFolder + L"\\" + RemotePrinter::RD_DRIVER_INF_PATH;
if (!FileExists(infFile))
{
WcaLog(LOGMSG_STANDARD, "Printer driver INF file not found, aborting...\n");
return;
}
if (!checkAddLocalPort(RD_PRINTER_PORT))
{
WcaLog(LOGMSG_STANDARD, "Failed to check add local port, error (%d)\n", GetLastError());
return;
}
else
{
WcaLog(LOGMSG_STANDARD, "Local port added successfully\n");
}
if (getInstalledDriverVersion(RD_PRINTER_DRIVER_NAME) > 0)
{
deletePrinter(RD_PRINTER_NAME);
if (FALSE == uninstallDriver(RD_PRINTER_DRIVER_NAME))
{
WcaLog(LOGMSG_STANDARD, "Failed to uninstall previous printer driver, error (%d)\n", GetLastError());
}
}
if (FALSE == installDriver(RD_PRINTER_DRIVER_NAME, infFile.c_str()))
{
WcaLog(LOGMSG_STANDARD, "Driver installation failed, still try to add the printer\n");
}
else
{
WcaLog(LOGMSG_STANDARD, "Driver installed successfully\n");
}
if (FALSE == addPrinter(RD_PRINTER_NAME, RD_PRINTER_DRIVER_NAME, RD_PRINTER_PORT))
{
WcaLog(LOGMSG_STANDARD, "Failed to add printer, error (%d)\n", GetLastError());
}
else
{
WcaLog(LOGMSG_STANDARD, "Printer installed successfully\n");
}
}
VOID uninstallPrinter()
{
deletePrinter(RD_PRINTER_NAME);
WcaLog(LOGMSG_STANDARD, "Deleted the printer\n");
uninstallDriver(RD_PRINTER_DRIVER_NAME);
WcaLog(LOGMSG_STANDARD, "Uninstalled the printer driver\n");
checkDeleteLocalPort(RD_PRINTER_PORT);
WcaLog(LOGMSG_STANDARD, "Deleted the local port\n");
}
}