# Dosh Native v1 Audit Packet

This is the handoff checklist for an external security review.

## Scope

Review the security properties of Dosh native v1:

- Native UDP authentication and key exchange
- Host key trust and known-host mismatch behavior
- Authorized key parsing and policy enforcement
- Transport encryption, replay protection, rekeying, resume, and stale packet handling
- Attach ticket sealing/opening
- TCP forwarding and agent forwarding authorization boundaries
- Parser robustness for untrusted wire/config data

Primary files:

- `src/native.rs`
- `src/protocol.rs`
- `src/auth.rs`
- `src/ssh_agent.rs`
- `src/bin/dosh-client.rs`
- `src/bin/dosh-server.rs`
- `src/config.rs`
- `tests/parser_robustness.rs`
- `tests/protocol_auth.rs`
- `tests/hostile_network.rs`
- `tests/integration_smoke.rs`
- `fuzz/fuzz_targets/*`

Primary docs:

- `docs/NATIVE_V1_SPEC.md`
- `docs/THREAT_MODEL.md`
- `docs/PROTOCOL_VERSIONING.md`
- `docs/PUBLIC_READINESS.md`
- `docs/RELEASE_EVIDENCE_2026-06-20.md`

## Required Reviewer Questions

1. Is the native handshake transcript complete enough to bind client/server keys,
   requested session, mode, env, and forwarding permissions?
2. Are host-key trust transitions fail-closed, especially unknown vs mismatch vs
   explicit TOFU?
3. Are authorized-key options parsed conservatively enough, and are unsupported
   options rejected safely?
4. Can replayed, reordered, delayed, stale, or cross-epoch packets affect terminal
   input or forwarded streams more than once?
5. Does key rotation preserve confidentiality without creating split-brain epoch
   states?
6. Do attach tickets create any bearer-token replay or privilege-extension issue?
7. Can UDP endpoint migration be abused for hijack or reflection?
8. Are local/remote/dynamic TCP forwarding and agent forwarding gated correctly by
   client opt-in, server config, and authorized-key options?
9. Are parser and packet-size limits sufficient against malicious inputs?
10. Are there any unsafe assumptions in process/session persistence or holder
    adoption?

## Current Local Evidence

As of 2026-06-20:

- `cargo test`: `153 passed, 1 ignored`
- `make soak-local`: passed 30-minute sleep/roaming soak
- `make fuzz-smoke`: passed all configured fuzz targets for 20s each
- `make bench-docker-mosh`: passed SSH, ControlMaster, native, cached, and Mosh
  comparison gates

## Explicit Non-Claims Before Audit

- No claim of generic SSH protocol replacement.
- No claim of full Mosh compatibility.
- No claim that native v1 is externally audited.
- No claim that Windows server support is production-ready.