# Developing with Visual Studio Code

# Overview

  1. Use Visual Studio Code and the Remote - SSH plugin to establish a vscode-ssh session.
  2. Tweak a project with a new Cargo.toml workspace and all Makefiles. This enables rls.
  3. Tweak the build options for compiling in debug mode.
  4. Use Native Debug plugin for graphic debugging.

# Prerequisites

  • Visual Studio Code installed on your machine. OS is flexible.
  • Remote Linux supports Intel SGX, with SSH service started.
  • rustup, Intel SGX driver/PSW/SDKs are correctly installed. hello-rust code sample works.
  • Remote Linux could be the same machine. Just ignore the vscode-ssh plugin mentioned in this wiki page and you'll be fine.

# Known bugs

  • sgx-gdb throws Python exception on gdb > 7.12 on some platforms, such as mine. But native sgx-gdb may not throw that error. Don't have a solution for VSCode yet.

# Steps

# Setup the vscode-ssh session.

  1. Setup a convenient way for ssh login. I always append my ~/.ssh/id_rsa.pub to the remote ~/.ssh/authorized_keys.
  2. Install the Remote - SSH plugin.
  3. Establish a vscode-ssh session to the remote Linux.

# Create an rls-friendly Teaclave SGX SDK project.

hello-rust-vscode-debug is an example. Differences between this and hello-rust are:

  1. An extra Cargo.toml at the root, which contains two Rust crates: app and enclave. This change would result in changing the path of target folders.
  2. Tweak Makefile and enclave/Makefile and correct the path of target folders.
  3. Tweak Makefile and enclave/Makefile to enable debug compilation. Changes include: (1) remove --release in cargo build, (2) add -ggdb to SGX_COMMON_FLAGS.

After these steps, the hello-rust-vscode-debug should be an rls-friendly project. And open the remote folder of it in the VSCode main screen "Start - open folder". Then autocompletion should work!

# Setup Native Debug with sgx-gdb

Now we have a vscode-ssh session to the remote Linux and an opened folder of hello-rust-vscode-debug. The next step is to configure a correct launch.json for Native Debug plugin. Now open the debug panel of VS code and click on the gear icon to open launch.json in the editor.

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Debug",
            "type": "gdb",
            "request": "launch",
            "target": "app",
            "cwd": "${workspaceRoot}/bin",
            "valuesFormatting": "parseText",
            "gdbpath": "sgx-gdb",
            "ssh": {
                "forwardX11": false,
                "host": "xxx", // your IP
                "cwd": "${workspaceRoot}/bin",
                 // SSH private key on remote machine. Add the pub key to ~/.ssh/authorized_keys
                 // This ssh configuration is established from host to host, because the current
                 // vscode session is "within a ssh session established by vscode-ssh".
                 // I think this might be a bug but can hardly be resolved.
                "keyfile": "/home/ding/.ssh/id_rsa", // private key
                "user": "xxx",
                "bootstrap": "source /opt/sgxsdk/environment",
                "port": 22
            }
        }
    ]
}

name,type,request,valuesFormatting are default values. cwd is the working directory we launch the app, so it should be the bin folder. target is the debugee executable so it should be the app. host is the IP address of your Linux machine. Then comes the tricky part: ssh. It means that we use an extra ssh session for debugger, within the current vscode-ssh session. This means that we are here creating an additional ssh session from remote machine to itself. Only in this way could we setup the environment using the Intel's script before launching sgx-gdb. So we need to add the public key ~/.ssh/id_rsa to ~/.ssh/authorized_keys and demonstrate the corresponding private key as ~/.ssh/id_rsa.

Having this launch.json configured correctly, we could simply set up a breakpoint on the first line of say_something and start debugging. Enjoy!

Last Updated: 10/27/2020, 8:49:48 PM