cdupuis/sbx-kit-github-yubikey:1.0.0

schemaVersion: "3"
displayName: GitHub via forwarded YubiKey (PIV)
description: |
    Prepares a sandbox for GitHub git over the forwarded host ssh-agent
    (YubiKey PIV slot 9a, served by docker-piv-agent). The private key and
    PIN never enter the sandbox — each git network op makes the HOST YubiKey
    blink for a tap, which the human approves. Pairs with host-side
    ssh-agent forwarding (the daemon's SSH_AUTH_SOCK at startup).

    What it does:
    - network-policy runtime: allow GitHub SSH egress. sbx egress is a
      TLS-intercepting HTTP(S) proxy, so raw SSH on port 22 is closed at kex
      by default; this opens it (also covers ssh.github.com:443 for the 443
      fallback).
    - lifecycle startup (idempotent; runs on every boot): accept
      GitHub's host key on first use (a non-TTY agent can't answer the
      interactive yes/no prompt), and rewrite any HTTPS github URL to SSH so
      all git traffic routes through the forwarded agent.
sourceUrl: https://github.com/docker/docker-piv-agent
version: 1.0.0
kind: mixin
capabilities:
    - type: com.docker.sandbox/network-policy@1
      config:
        runtime:
            allow:
                - github.com:22
                - ssh.github.com:443
    - type: com.docker.sandbox/lifecycle@1
      config:
        startup:
            - command:
                - sh
                - -c
                - mkdir -p ~/.ssh && chmod 700 ~/.ssh && (grep -q "StrictHostKeyChecking accept-new" ~/.ssh/config 2>/dev/null || printf "Host github.com\n  StrictHostKeyChecking accept-new\nHost ssh.github.com\n  StrictHostKeyChecking accept-new\n" >> ~/.ssh/config)
              description: Accept GitHub host key on first use (non-TTY agent has no prompt)
              user: agent
            - command:
                - sh
                - -c
                - git config --global url."[email protected]:".insteadOf "https://github.com/"
              description: Route github HTTPS -> SSH (use forwarded YubiKey agent)
              user: agent
            - command:
                - sh
                - -c
                - 'if [ -S "$SSH_AUTH_SOCK" ]; then echo "github-yubikey kit: forwarded agent OK ($SSH_AUTH_SOCK)"; ssh-add -l 2>&1 | head -1; else echo "github-yubikey kit: ERROR no SSH_AUTH_SOCK — host agent not forwarded (start sbx from a shell with SSH_AUTH_SOCK set)"; exit 1; fi'
              description: Diagnostic — report forwarded ssh-agent state
              env:
                - SSH_AUTH_SOCK
              user: agent
            - command:
                - sh
                - -c
                - ssh-add -L | grep -m1 docker-piv-agent > ~/.ssh/piv_signing.pub || ssh-add -L | head -1 > ~/.ssh/piv_signing.pub
              description: Write YubiKey PIV signing public key to ~/.ssh/piv_signing.pub
              env:
                - SSH_AUTH_SOCK
              user: agent
            - command:
                - sh
                - -c
                - git config --global gpg.format ssh && git config --global user.signingkey ~/.ssh/piv_signing.pub && git config --global commit.gpgsign true && git config --global tag.gpgsign true
              description: Configure git to use YubiKey PIV for signing
              user: agent