Johnathan Corgan
8b396b662d
A native API flow's descriptor reaches the client inside a message: an arrival for a flow a listener accepts, or a connect or listen reply. The daemon closed its own copy once the message was written, so until the client read it, the message was the only reference to the socket. xnu's descriptor collector flushes a socket in that state, and the client then receives a flow that reads as end of file with the datagrams the daemon held for it gone. That is the intermittent macOS failure of the two listener tests. A listener now keeps the daemon's copy of each flow it hands over until the client's first write on the flow, the listener's close, or the flow's end, on every platform the listener builds on. The flow is recorded before its reader starts, so a write already queued cannot race the record. The connection's serving loop, now a method on the connection so a test can run it over a real socket, keeps the copy sent in a connect or listen reply until the client's next command on that connection or the connection's end of file. A client sends its next command only after reading the reply, so either event means the descriptor has left the message. The shipped client closes the connection as soon as it has the reply, so it sees no change. The cost is accepted and documented: a flow a client accepts and closes without ever writing stays open, holding its port and a flow slot, until the listener closes, so a server that refuses flows by dropping them pays for each one until then; a client speaking the protocol directly that leaves its setup connection open sees a flow or listener it closes stay open until its next command or the connection's close. The reference and how-to pages, the client rustdoc on FipsStream, FipsListener and accept, and the design note say so, and the security reference records that a remote peer opening flows from many source ports to such a server can exhaust the node-wide max_flows ceiling. Tests cover an arrival surviving a provoked collection (deterministic on macOS), a held flow outliving its dropped descriptor until the listener closes, a client's write releasing it, a flow its client still holds working after the listener has closed and let its copy go, and a reply's copy kept until the next command and let go when the connection ends. The native API harness asserts the new lifetime of a refused flow. On macOS and FreeBSD the daemon notices a client's close only when a reader retries its read, up to a quarter second later, so the test helpers that wait for a close (forgotten, rebind, settle_closed) retry for up to five seconds by the clock rather than for a count of yields, and still_open waits two retry intervals there before asserting a flow is still open.
FIPS Documentation
FIPS (Free Internetworking Peering System) is a self-organizing encrypted mesh network built on Nostr identities, capable of operating over arbitrary transports — local networks, the public internet, Tor, Bluetooth, or point-to-point links — without central infrastructure.
With FIPS, your machine becomes a node in the mesh with a self-generated cryptographic identity. There are two ways to deploy it.
As an overlay on top of existing IP networks, FIPS lets your node reach any other FIPS node wherever it sits — behind a NAT, on a different ISP, on a phone over cellular, on a laptop with only Bluetooth in range, or behind a Tor onion. The mesh forwards IPv6 traffic transparently and end-to-end encrypted, with no central VPN concentrator or coordinating server.
From the ground up over raw Ethernet, WiFi, or Bluetooth, FIPS provides a complete permissionless network without any pre-existing IP infrastructure, ISP, or DNS. Any node that joins the link gets routable IPv6 addresses, peer discovery, and a path to every other node automatically.
Either way, existing networking software runs over it unchanged: SSH, HTTP servers, file transfer, anything IPv6-native works the same way it would on a local network.
New to FIPS? Start with the Getting Started guide.
Documentation Sections
Tutorials
If you are starting from scratch and want a guided path to a working mesh, go here.
How-To Guides
If you have a specific task in mind — enabling a feature, deploying a component, diagnosing a problem — go here.
Reference
If you need to look up wire formats, configuration keys, command flags, or counter inventories, go here.
Design
If you want to understand how the mesh self-organizes, why FIPS makes the choices it does, or how the pieces fit together, go here.
Releases
If you want the notes for a particular version — what changed, what broke, and what to do about it on upgrade — go here.