Bitwarden SSH Agent relay to WSL2

wsl2-bitwarden-ssh-agent.sh

#!/bin/bash
set -e

echo "Installing npiperelay..."
/mnt/c/WINDOWS/system32/cmd.exe /c "winget install --id=albertony.npiperelay -e --accept-source-agreements --accept-package-agreements"

echo "Installing socat..."
sudo apt-get update
sudo apt-get install -y socat iproute2

echo "Creating SSH agent bridge script..."

SCRIPT_DIR="$HOME/.local/bin"
mkdir -p "$SCRIPT_DIR"

cat << 'EOF' > "$SCRIPT_DIR/agent-bridge.sh"
#!/bin/bash

mkdir -p "$HOME/.ssh"
chmod 700 "$HOME/.ssh"

export SSH_AUTH_SOCK="$HOME/.ssh/agent.sock"

NPIPERELAY_WIN=$(
    /mnt/c/WINDOWS/system32/cmd.exe /c "where npiperelay.exe" 2>/dev/null |
        tr -d '\r' |
        head -n 1
)

if [ -z "$NPIPERELAY_WIN" ]; then
    echo "npiperelay.exe was not found in Windows PATH" >&2
    return 1 2>/dev/null || exit 1
fi

NPIPERELAY="$(wslpath -u "$NPIPERELAY_WIN")"

if [ ! -x "$NPIPERELAY" ]; then
    echo "npiperelay.exe is not executable from WSL: $NPIPERELAY" >&2
    return 1 2>/dev/null || exit 1
fi

if ! ss -a 2>/dev/null | grep -Fq -- "$SSH_AUTH_SOCK"; then
    rm -f "$SSH_AUTH_SOCK"
    (
        setsid socat \
            "UNIX-LISTEN:$SSH_AUTH_SOCK,fork" \
            "EXEC:$NPIPERELAY -ei -s //./pipe/openssh-ssh-agent,nofork" \
            &
    ) >/dev/null 2>&1
fi
EOF

chmod +x "$SCRIPT_DIR/agent-bridge.sh"

echo "Ensuring bridge script is sourced in .bashrc..."

BASHRC="$HOME/.bashrc"
BRIDGE_SOURCE='source ~/.local/bin/agent-bridge.sh'

touch "$BASHRC"

if ! grep -Fxq "$BRIDGE_SOURCE" "$BASHRC"; then
    printf '\n%s\n' "$BRIDGE_SOURCE" >> "$BASHRC"
    echo "Added agent bridge script to .bashrc"
else
    echo "Bridge script already sourced in .bashrc"
fi

echo "Setup complete! Restart your shell or run:"
echo "  source ~/.local/bin/agent-bridge.sh"

curl -fsSL https://gist.githubusercontent.com/espresso3389/6fbbe818cb98b6bab1e73cb39a0aee64/raw/wsl2-bitwarden-ssh-agent.sh | bash