Saturday, April 22, 2023

How to Use 1Password SSH Agent with WSL2 (on Windows 11)

Note:
- Always look for the official documentation, this tutorial may not suit you as there are new updates to the installation process.
- References are at the end of the document.
Was used:
- Windows 11 (x64)
- WSL 2 (Ubuntu 22.04.2 LTS)
- 1Password (for Windows 8.10.5)

Install WSL2 (on Windows 11)

Windows 11 makes it easy to install WSL, basically you need to run these commands:

In your PowerShell(admin) or CMD(admin):

Run the command to install WSL2, and restart the computer.

# The command will install WSL alongside the Ubuntu distribution.
wsl –install
# Or, to install WSL with a specific distro, run the command:
wsl –install -d <distro-name>

Other Useful Commands:

# Checking the image version
wsl --list --verbose

# Selecting Distro as Main
wsl --setdefault <distro-name>

# If you need to remove a distro
wsl --unregister <distro-name>

# If necessary, kill the WSL process
wsl --shutdown

1. Enable 1Password SSH Agent

Open your 1Password settings and go to the “Developer” section. You need to check the “Use the SSH agent” checkbox.
- If you have not created or imported your SSH keys into 1Password, you can do it by following this youtube video or these articles:
  - Manage SSH keys
  - Authorize Git with ease (in the second stage)

2. Download npiperelay

This tool (npiperelay) is used for communication between WSL and the 1Password SSH agent. It uses WSL to communicate with Windows Named Pipes.
1. Download npiperelay from the GitHub repository
2. Unzip it, and paste the npiperelay.exe file in any folder that's configured in your system's PATH.
  - If you don't know how to modify your system's PATH... Example Here
```
# 1. Create a folder at an address like this
C:\Users\my-user\folder-npiperelay
# 2. Create PATH Environment Variable on Windows
# 3. Run npiperelay.exe
```

3. Connect WSL with 1Password's SSH agent

In your WSL distribution:

"We need to install socat which is a utility to transfer data between channels, this tool will use npiperelay to then communicate with the named pipes"
```
sudo apt install socat
```

Create a new file named .agent-bridge.sh in your home directory

touch $HOME/.agent-bridge.sh && chmod +x $HOME/.agent-bridge.sh

(IMPORTANT) Create the folder on your root for the agent.sock (How mentioned by @rfay and @Lochnair in the comments) or if you prefer, add the content on .agent-bridge.sh at the top of the step bellow
```
mkdir -p ~/.1password
```

Paste content into File: .agent-bridge.sh

# Code extracted from https://stuartleeks.com/posts/wsl-ssh-key-forward-to-windows/ 

# (IMPORTANT) Create the folder on your root for the `agent.sock` (How mentioned by @rfay and @Lochnair in the comments)
# mkdir -p ~/.1password

# Configure ssh forwarding
export SSH_AUTH_SOCK=$HOME/.1password/agent.sock
# need `ps -ww` to get non-truncated command for matching
# use square brackets to generate a regex match for the process we want but that doesn't match the grep command running it!
ALREADY_RUNNING=$(ps -auxww | grep -q "[n]piperelay.exe -ei -s //./pipe/openssh-ssh-agent"; echo $?)
if [[ $ALREADY_RUNNING != "0" ]]; then
    if [[ -S $SSH_AUTH_SOCK ]]; then
        # not expecting the socket to exist as the forwarding command isn't running (http://www.tldp.org/LDP/abs/html/fto.html)
        echo "removing previous socket..."
        rm $SSH_AUTH_SOCK
    fi
    echo "Starting SSH-Agent relay..."
    # setsid to force new session to keep running
    # set socat to listen on $SSH_AUTH_SOCK and forward to npiperelay which then forwards to openssh-ssh-agent on windows
    (setsid socat UNIX-LISTEN:$SSH_AUTH_SOCK,fork EXEC:"npiperelay.exe -ei -s //./pipe/openssh-ssh-agent",nofork &) >/dev/null 2>&1
fi

Add the following line at the end of the file .bashrc
```
source $HOME/.agent-bridge.sh
```

4. Finally last step

Reset your Windows Terminal and you should be able to see your keys imported into 1Password when listing the keys added to the agent.
Try this command on your WSL2 and if it returns your keys, congratulations you finished the setup!
```
ssh-add -l
```

References

Links:
- Using 1Password's SSH Agent with WSL2
- How to change the PATH environment variable in Windows

zhiyue/wsl2-with-1password-info.md