forkidentity: drop a per-fork identity record into every fork#217
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forkidentity: drop a per-fork identity record into every fork#217sjmiller609 wants to merge 1 commit intomainfrom
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When N forks come up off the same restored memory snapshot they share /dev/urandom state, machine-id, hostname, and clock — which silently breaks crypto and makes fan-out forks indistinguishable. This change adds lib/forkidentity, a small package that produces a fresh per-fork record (256 bytes of crypto-rand entropy plus a small forward clock jitter) and atomically writes it as fork-identity.json into the fork's data directory. forkInstanceFromStoppedOrStandby now calls it on every fork before metadata save. The hypervisor side never touches guest state. A future guest-agent change reads this file at boot and applies it: reseeds /dev/urandom, refreshes machine-id, and steps the clock by ClockOffsetNs. Failure to build/write the record is fatal because identity reuse is a security regression, not a soft warning. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
lib/forkidentitypackage:Build(forkID)produces an identity with 256 bytes of crypto-rand entropy + a small forward clock jitter;Write(dir, id)atomically writesfork-identity.jsoninto the fork's data directory;Read(dir)loads it.writeForkIdentityintoforkInstanceFromStoppedOrStandbyso every fork drops a fresh record before metadata save.Why
When N forks come up off the same restored memory snapshot they share
/dev/urandomstate, machine-id, hostname, and clock. That silently breaks crypto (TLS keys, JWTs) and makes fan-out forks indistinguishable to operators. Hypeman can't safely rewrite guest state directly, but it can plant a small record that a guest agent (separate work) reads at boot to reseed/dev/urandom, refresh machine-id, and step the clock byClockOffsetNs.Test plan
go test ./lib/forkidentity/...go test ./lib/instances/... -run "TestForkInstance|TestValidateFork|TestForkRequest"<fork>/fork-identity.jsonexists, hasversion: 1, has 256-byteentropy_seed, and a smallclock_offset_ns🤖 Generated with Claude Code