feat: control-plane egress relay (decision 19)#6
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Decision 19 (DESIGN §3): coxswain reaches a node through a relay so the node never sees coxswain's IP. coxswain opens a substream on its outbound tunnel, writes a one-line CONNECT target, and the relay dials it over raw TCP and pumps bytes both ways. The relay is protocol-blind — the gRPC-mTLS or SSH payload is end-to-end secured and opaque to it — so one generic relay serves both control channels. This is the core mechanism (CONNECT codec + relay Serve + controller Open), transport-abstracted so it is unit-testable over an in-memory substream. The egress tunnel (inverted-direction yamux) and the coxswain dialer wiring (gRPC WithContextDialer + SSH net.Dialer) build on it next. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
`beacon egress` runs the relay side of decision 19: coxswain dials in on --tunnel-addr (mutual TLS, relay cert + Fleet-CA-verified coxswain), and each substream coxswain opens carries a CONNECT target that beacon dials over raw TCP and pipes via egress.RunRelay. Protocol-blind — no device-ca needed on this leg (no caravel clients), reuses run's relay.crt/key + fleet-ca.crt. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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The egress PR (#6) committed only egress.go — the transport file (ClientSession, AcceptAndServe, RunRelay) was left untracked, so `beacon egress`, which calls egress.RunRelay, failed to compile on main. Add tunnel.go + tunnel_test.go (inverted-direction yamux: coxswain opens substreams, the relay accepts and dials the node), with the multiplexing round-trip test. main builds again. Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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beacon's egress package is on main now (PharosVPN/relay#6, #7), so bump the beacon dependency to it and remove the development `replace => ../beacon`. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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…32) * feat(egress): coxswain egress tunnel + relay-routed gRPC/SSH dialers Decision 19: coxswain reaches nodes through a relay so a node never sees coxswain's IP. internal/egress.Tunnel TLS-dials the relay, holds a yamux client session (lazy reconnect on a dead session), and exposes DialContext — the single chokepoint both control channels route through: - gRPC NodeControl: control.NewDialer gains WithContextDialer. - SSH: ssh.DialConfig gains an optional Dialer. Both opt-in and backward-compatible — direct dial stays the default. The mTLS and SSH handshakes run end-to-end over the relayed conn, so the relay is protocol-blind. Full coxswain->relay->node path (and lazy reconnect) proven in internal/egress tests against beacon's egress relay. Dev: go.mod replaces github.com/PharosVPN/beacon => ../beacon for the new egress package; drop once beacon's egress branch lands and the dep is bumped. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> * chore(egress): use merged beacon egress; drop dev replace beacon's egress package is on main now (PharosVPN/relay#6, #7), so bump the beacon dependency to it and remove the development `replace => ../beacon`. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> --------- Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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The relay side of control-plane egress relaying (DESIGN decision 19): coxswain reaches a node through beacon so the node never sees coxswain's IP.
egresspackage — protocol-blind: coxswain opens a substream and writes a one-line CONNECT target; beacon dials it over raw TCP and pumps bytes both ways. The gRPC-mTLS / SSH payload is end-to-end and opaque to the relay. Inverted-direction yamux vs the ingress tunnel (coxswain opens, relay accepts). Codec + transport unit-tested, incl. multiplexing.beacon egressCLI — runnable relay; reusesrun's relay.crt/key + fleet-ca.crt (no device-ca on this leg).Consumed by coxswain via PharosVPN/coxswain#32 (which currently uses a dev
replaceto this branch — bump the dep + drop the replace once this lands).🤖 Generated with Claude Code