How to use the WinRM C++ API in a simple example - c++

Question

why is my code failing to run a simple executable using WinRM's C++ API?
//main.cpp
int main()
{
ShellClient *shellClient = new ShellClient();
//Set up the shell client here and connect to the localhost.
//This seems to be working fine because I'm handling every
//possible error code, and none of them are being triggered
PCWSTR commandLine = L"\"MyExampleExecutable.exe\"";
isOk = shellClient->RunCommand(commandLine);
if (!isOk)
return 1;
return 0;
}
//ShellClient.cpp
bool ShellClient::RunCommand(PCWSTR command)
{
WSMAN_SHELL_ASYNC createCommandAsync;
ZeroMemory(&createCommandAsync, sizeof(createCommandAsync));
createCommandAsync.operationContext = this;
createCommandAsync.completionFunction = (WSMAN_SHELL_COMPLETION_FUNCTION)CommandCreatedCallback;
WSManRunShellCommand(shellHandle, 0, command, NULL, NULL, &createCommandAsync, &commandHandle);
if (commandHandle == NULL)//It is *always* NULL
{
std::cout << "command handle null" << std::endl;
system("pause");
return false;
}
return true;
}
One possible clue is that my C++ code thinks the shell gets created fine, but in the Event Viewer for my machine, there is this:
WSMan operation CreateShell failed, error code 2150859250
At the time of writing, this lovely error code gives precisely zero results when put into Google, making it rather difficult to know what it means.
Background and common solutions which I have already checked
As documented here and explaned in this video by the same author, most WinRM issues boil down to either connection or authentication problems. In my case, if I deliberately enter incorrect user credentials, I get an authentication error, so I know that my program is connecting and authenticating fine when the correct username and password are supplied. Also:
From the command line, I can connect to my local machine and pretend it's a remote server, for example the following command works fine:
winrs -r:http://localhost:5985 -u:COMPUTERNAME\Jeremy "dir"
winrm quickconfig shows the service is working (which we already know otherwise the winrs command wouldn't work)
winrm get winrm/config shows TrustedHosts = localhost, AllowUnencrypted = true, and all authentication methods are set to true
Following this advice, I have set the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\LocalAccountTokenFilterPolicy = 1
Working in Windows 10
Thank you in advance!

Answer 1

I wasn't aware of this so can't comment on whether it's common knowledge but Microsoft have a nifty error lookup tool where you can enter an error code (after converting it from a normal number to hexadecimal) and it tells you what it means.
In this case, 2150859250 (803381F2 in hex) corresponds to:
ERROR_WINRS_IDLETIMEOUT_OUTOFBOUNDS wsmerror.h
# The WS-Management service cannot process the request. The
# requested IdleTimeout is outside the allowed range.
When setting up the WinRM shell, I was doing the following:
WSMAN_SHELL_STARTUP_INFO startupInfo;
ZeroMemory(&startupInfo, sizeof(startupInfo));
startupInfo.idleTimeoutMs = 1000;//not large enough!
startupInfo.workingDirectory = L"C:\\";
//other parameters of startupInfo set here
WSManCreateShell(session, 0, shellUri, &startupInfo, NULL, NULL, &createShellAsync, &shellHandle);
Changing idleTimeoutMs from 1000 to a much larger number like 100000 solved the error and my program now works fine.
Since the official docs for this parameter say anything between 0 and 0xFFFFFFFF are valid, it remains a mystery why a value of 1000 is throwing this error. I leave this for somebody more knowledgable than myself to answer, on the off chance that they come across this question.