Codex review: the /31 TAP doesn't make source IP unspoofable, and the
app-layer token was returned by launch but never delivered or enforced, so
a spoofed source could select a victim bottle's policy/tokens. Make the
token mandatory and deliver it on each attributed plane (anti-spoof landed
separately as the network boundary).
Enforcement (control plane):
- `Orchestrator.resolve` now requires a matching (source_ip, identity_token)
pair (constant-time) — no source-IP-only fallback. `/resolve` fail-closes
(403) on a missing/empty/mismatched token.
Delivery, per plane (the token is `token_urlsafe`, safe in a URL):
- egress: proxy credentials (`HTTPS_PROXY=http://bottle:<token>@gw`). The
addon reads `Proxy-Authorization` — from the request (HTTP) or captured at
the CONNECT for HTTPS tunnels (keyed by client conn, cleared on disconnect)
— validates, and strips it (+ the legacy header) before upstream.
- git-http: a URL-scoped `http.<gate>/.extraHeader: x-bot-bottle-identity`
in the agent's git config (only over the http transport).
- supervise: `mcp add --header x-bot-bottle-identity: <token>` (claude +
codex); the server reads the header and passes it to resolve.
Wiring: thread `ctx.identity_token` onto the firecracker + docker plans and
into the agent env/config at launch.
Verified on a KVM host: egress with the correct proxy-cred token returns
200 (HTTP and HTTPS/CONNECT), and no-token / wrong-token return 403; a real
`cli.py start --backend=firecracker` launch provisions git config + the
supervise MCP header and reaches the agent session, all under mandatory
enforcement. Fixed a `claude mcp add` arg-order bug (--header must follow
the positional name/url) found by that launch.
Transparent proxy for tools that ignore proxy env is deferred to a
follow-up (see thread); anti-spoof + host firewall remain the fail-closed
boundary.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WBMWTEtQdJ4W5UrWuLHCck
Completes the de-sidecar cleanup: no live code, test, current doc,
script, or nix file mentions or is named "sidecar" any more. Only the
dated PRD/research docs keep the term as historical record (agreed on
the #385 thread).
- Rename `sidecar_init.py`→`gateway_init.py` was done earlier; this pass
sweeps the remaining descriptive uses: the egress / git-gate / supervise
components are the gateway's *daemons*, the shared container is the
*gateway*, the old per-bottle container was the *companion container*.
- Rename `tests/integration/test_sidecar_bundle_image.py`→`test_gateway_image.py`
and its class; update `docs/ci.md` + `tests/README.md` for the renamed/
removed integration tests.
- `SIDECAR_PORTS` shell var in `scripts/firecracker-netpool.sh`→`GATEWAY_PORTS`.
Full unit suite green (bar the pre-existing `/bin/sleep`-missing env
errors in test_gateway_init); docker integration — gateway singleton,
broker, real two-bottle multitenant isolation, and the gateway-image
build — all pass.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WBMWTEtQdJ4W5UrWuLHCck
Adds a Firecracker-based backend for Linux, providing mature KVM-based
microVM isolation to replace smolmachines/libkrun (issue #342, closes
the dead-end tracked in #332).
Architecture:
- Guest control over SSH (dropbear injected into the rootfs) on a
point-to-point TAP link. `ssh -t` forwards SIGWINCH natively, so no
resize bridge is needed.
- Networking: a one-time, root-provisioned pool of user-owned TAP
devices (no shared bridge → no docker0/virbr0/cni0 collisions) plus a
dedicated `table inet bot_bottle_fc` nftables table (independent of
Docker/ufw/firewalld rules). `./cli.py firecracker setup` prints the
host-appropriate config (NixOS module or sudo script).
- Rootfs: `docker export` → ext4 via `mke2fs -d` (rootless, no mount),
cached by image digest; per-bottle SSH pubkey + IP passed via the
kernel cmdline.
- Sidecar: reuses the Docker bundle, published on the slot's host TAP IP.
- Fail-closed isolation: TAP pool verified at preflight; the egress
boundary is proven empirically post-boot (before the agent runs) by a
canary probe — the VM must fail to reach the host directly, or launch
is refused.
Linux hosts with Firecracker + KVM now default to this backend;
macOS stays on macos-container.
Not yet validated end-to-end on live hardware (requires the one-time
network pool). Unit tests + pyright pass.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01G8p32HJgPoS1hLPWubbftM
didericis