RunAs

1.3

RunAs.psm1

Add-Type -TypeDefinition @'
using System;
using System.ComponentModel;
using System.Diagnostics;
using System.Management.Automation;
using System.Runtime.InteropServices;
using System.Security.Principal;

public static class RunAs
{
    [StructLayout(LayoutKind.Sequential)]
    private struct PROCESS_INFORMATION
    {
        public IntPtr hProcess, hThread;
        public uint dwProcessId, dwThreadId;
    }

    [StructLayout(LayoutKind.Sequential)]
    private struct STARTUPINFO
    {
        public int cb;
        public string lpReserved, lpDesktop, lpTitle;
        public uint dwX, dwY, dwXSize, dwYSize, dwXCountChars, dwYCountChars, dwFillAttribute, dwFlags;
        public short wShowWindow, cbReserved2;
        public IntPtr lpReserved2, hStdInput, hStdOutput, hStdError;
    }

    [DllImport("advapi32", CharSet = CharSet.Unicode, SetLastError = true)]
    private static extern bool CreateProcessWithLogonW(string userName, string domain, string password, int logonFlags, string applicationName, string commandLine, int creationFlags, IntPtr environment, string currentDirectory, ref STARTUPINFO startupInfo, out PROCESS_INFORMATION processInformation);
    [DllImport("userenv")]
    private static extern bool CreateEnvironmentBlock(out IntPtr lpEnvironment, IntPtr hToken, bool bInherit);
    [DllImport("userenv")]
    private static extern bool DestroyEnvironmentBlock(IntPtr lpEnvironment);
    [DllImport("kernel32")]
    private static extern bool CloseHandle(IntPtr hObject);

    private static void SplitUsername(string username, out string user, out string domain)
    {
        var parts = username.Split('\\', '@');
        if (parts.Length == 1)
        {
            user = parts[0];
            domain = Environment.UserDomainName;
        }
        else if (username.Contains("@"))
        {
            user = parts[0];
            domain = parts[1];
        }
        else
        {
            user = parts[1];
            domain = parts[0];
        }
    }

    public static void Start(PSCredential credential, bool noProfile, bool env, bool netOnly, string applicationName, string commandLine, string currentDirectory)
    {
        var s = new STARTUPINFO();
        s.dwFlags = 1; // STARTF_USESHOWWINDOW
        s.wShowWindow = 1; // SW_SHOWNORMAL
        s.cb = Marshal.SizeOf(typeof(STARTUPINFO));

        int logonFlags = 1; // LOGON_WITH_PROFILE
        if (noProfile) logonFlags = 0;
        if (netOnly) logonFlags = 2; // LOGON_NETCREDENTIALS_ONLY

        IntPtr lpEnvironment = IntPtr.Zero;
        int creationFlags = 0x04000000; // CREATE_DEFAULT_ERROR_MODE
        if (env)
        {
            CreateEnvironmentBlock(out lpEnvironment, IntPtr.Zero, false);
            creationFlags |= 0x00000400; // CREATE_UNICODE_ENVIRONMENT
        }

        try
        {
            string domain, username;
            SplitUsername(credential.UserName, out username, out domain);

            PROCESS_INFORMATION p;
            if (!CreateProcessWithLogonW(username, domain, credential.GetNetworkCredential().Password, logonFlags, applicationName, commandLine, creationFlags, lpEnvironment, currentDirectory, ref s, out p))
                throw new Win32Exception(Marshal.GetLastWin32Error());

            CloseHandle(p.hProcess);
            CloseHandle(p.hThread);
        }
        finally
        {
            if (env) DestroyEnvironmentBlock(lpEnvironment);
        }
    }
}
'@

function RunAs ([switch]$noProfile, [switch]$env, [switch]$netOnly, [Parameter(Mandatory=$true)][PSCredential]$user, [Parameter(Mandatory=$true)][string]$program, [Parameter(ValueFromRemainingArguments=$true)][string]$arguments) {
    try {
        if (!(test-path $program)) {
            $cmd = (get-command $program -ea ignore)
            if ($cmd -and $cmd.path) { $program = $cmd.path }
        }
        [RunAs]::Start($user, $noProfile, $env, $netOnly, $program, " $([Environment]::ExpandEnvironmentVariables($arguments))", $pwd.Path)
    }
    catch { write-error $_.Exception.Message }
<#
.Synopsis
    A version of the Windows 'runas' command that accepts a PSCredential instead of prompting for a password.
.Description
    Allows a user to run specific tools and programs with different permissions than the user's current logon provides.
.Parameter noprofile
    Specifies that the user's profile should not be loaded. This causes the application to load more quickly, but can cause some applications to malfunction.
.Parameter env
    To use current environment instead of user's.
.Parameter netonly
    Use if the credentials specified are for remote access only.
.Parameter user
    Username should be in form user@domain or domain\user.
.Parameter program
    Command line for EXE. See below for examples.
.Example
    ...
    runas -noprofile -user mymachine\administrator cmd
    runas -env -user mydomain\admin mmc %windir%\system32\eventvwr.msc
    runas -env -user user@domain.microsoft.com notepad "my file.txt"
#>
}

Export-ModuleMember -function RunAs