tiny.reticulum.interface

1//! The code every frame on one network interface carries to show it belongs2//! there, and the two calls that add it on the way out and check it on the way3//! in.4//!5//! An operator running a closed network over a shared medium wants its nodes to6//! take each other's frames and nothing else. The check runs on every frame in7//! both directions, so it has to be cheap and it has to work in the buffer the8//! caller already holds.9//!10//! A shared secret sent in the clear on every frame is readable by anyone11//! listening, so what goes on the wire has to prove knowledge of the secret12//! without carrying it. A frame that still looks like a Reticulum packet to an13//! outsider announces that the network is there. A check that stops at the14//! first byte that disagrees tells an attacker how much of a guess was right.15//!16//! The subtree follows Reticulum 1.5.0, the reference implementation, pinned to17//! one upstream commit by the package README and the generated conformance18//! corpus. What it takes is the key derivation of Reticulum@1.5.019//! RNS/Reticulum.py:989-1002, the masking of Reticulum@1.5.020//! RNS/Transport.py:1244-1276, and the checking of Reticulum@1.5.021//! RNS/Transport.py:1648-1694. The package generates masked frames and verdicts22//! from that release and replays them in tests, so each of those claims is23//! checkable from this tree.24//!25//! The code a frame carries to show it belongs on one network interface (the26//! *access code*) is the tail of an Ed25519 signature over the packet, from one27//! to 64 bytes of it, taken under a key derived from the network's name and28//! key, so the secret stays off the wire. Every other byte of the frame is29//! combined with derived bytes (the *mask*) seeded by that code, which leaves30//! the frame looking like unstructured bytes to anyone without the key.31//! Checking recomputes the signature over the recovered packet and compares it32//! against the carried code over a fixed 64 bytes, so the comparison takes the33//! same time whatever the bytes are. Both directions refuse a call whose input34//! and output buffers overlap.35//!36//! - *interface key*: the 64 bytes derived from a network name and a network37//!   key, which both sign the access code and key the mask.3839pub const ifac = @import("ifac.zig");

1pub const interface = @import("interface/root.zig");