InterProcess Communication

[BinToss]

Related Issues

• InterProcess Communication AmaiSosu#20
• InterProcess Communication HXE#289
• InterProcess Communication SPV3.Loader#122

Purposes

MCC process inspection

NOTE: this may be deprecated by HaloSPV3/HXE#288 in the future. In which case, we can instead check a process's executable path to find MCC's root directory.

Details

Only a 64-bit process can inspect another 64-bit process's modules.
HXE can remain 32-bit if this functionality is offloaded to a 64-bit app.

Embedding a small app within HXE to be extracted when needed seems to be the best delivery option. The alternative is to download the latest release during the Compile stage so it is embedded in the Install payload.

Elevated Operations When Access Is Denied

Details

If the current process tries to access a filesystem, registry, process, etc. resource and is denied access due to insufficient permissions, we can start an elevated sub-process and tell it what to do via IPC.

When a User process attempts to access an Elevated process, they will be greeted with

Unhandled exception. System.ComponentModel.Win32Exception (5): Access is denied.
   at System.Diagnostics.ProcessManager.OpenProcess(Int32 processId, Int32 access, Boolean throwIfExited)  
   at System.Diagnostics.Process.GetProcessHandle(Int32 access, Boolean throwIfExited)
   at System.Diagnostics.Process.GetOrOpenProcessHandle()
   at System.Diagnostics.Process.get_SafeHandle()

Solutions

https://www.c-sharpcorner.com/article/inter-process-communication/

gRPC

https://devblogs.microsoft.com/dotnet/grpc-in-dotnet-6/
https://docs.microsoft.com/en-us/dotnet/architecture/grpc-for-wcf-developers/rpc-types
https://docs.microsoft.com/en-us/aspnet/core/grpc/?view=aspnetcore-6.0
You can use gRPC with an IPC transport like Unix domain sockets
https://github.com/grpc/grpc-dotnet
https://www.nuget.org/profiles/grpc-packages
https://www.nuget.org/packages/Grpc.Net.Client
https://www.nuget.org/packages/Grpc.Net.ClientFactory

IpcServiceFramework

can be configured to work over TCP or named pipes.

JSON RPC

JSON-RPC.NET

StreamJsonRpc

Can be used over most streams. Works with Pipes, WebSockets, etc, and has testability built-in.

Pipes

How to: Use Anonymous Pipes for Local Interprocess Communication
using Streams over a Pipe is the best way if I want to avoid a web service or gRPC/http

MessagePipe

PipeMethodCalls

https://nicolasdeory.medium.com/simple-ipc-using-named-pipes-in-net-core-7cb1b29f6dab

Protobuf

https://johnkoerner.com/csharp/IPC-in-net-core-using-protobuf/

WCF

https://docs.microsoft.com/en-us/dotnet/framework/wcf/feature-details/duplex-services
https://stackoverflow.com/a/56135/14894786

zeroMQ