Implement identity management for the FIPS daemon with two modes:
Ephemeral (default): A fresh keypair is generated on every start.
Key files (fips.key, fips.pub) are written for operator visibility
but overwritten on each restart. This is privacy-friendly and
requires no configuration.
Persistent (opt-in via `node.identity.persistent: true`): Uses
three-tier identity resolution:
1. Explicit nsec in config file (advanced users)
2. Persistent key file alongside config (reused across restarts)
3. Generate new keypair, persist to key file
Key files follow the SSH id_ed25519/id_ed25519.pub convention:
- fips.key: bare bech32 nsec string, mode 0600
- fips.pub: bare bech32 npub string, mode 0644
The daemon always writes fips.pub on startup so operators can
find their current identity via `cat /etc/fips/fips.pub`.
Identity resolution extracted into testable `resolve_identity()`
function in config module. Graceful degradation: key file write
failure silently falls back to ephemeral identity.
Add `fipsctl keygen` subcommand for manual key generation:
- `-d <dir>` output directory (default: /etc/fips)
- `-f` force overwrite existing files
- `-s` print nsec/npub to stdout instead of writing files
- Warns that `persistent: true` must be set in config
- Works without a running daemon
Includes unit tests for key file read/write roundtrip, file
permissions, whitespace trimming, empty file error, path derivation,
ephemeral-by-default behavior, ephemeral key cycling, persistent
key file loading, and persistent generate-and-reuse lifecycle.
Add a Unix domain socket interface for querying node state at runtime.
A spawned tokio task accepts connections and communicates with the main
event loop via mpsc/oneshot channels, keeping all Node access
single-threaded.
Includes:
- src/control/ module with socket lifecycle, JSON protocol, and 11
query handlers (status, peers, links, tree, sessions, bloom, mmp,
cache, connections, transports, routing)
- Separate fipsctl binary for CLI queries (fipsctl show <command>)
- ControlConfig in node configuration (enabled, socket_path)
- Integration into the main select! event loop