tiny.reticulum.wire

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

1//! The byte layouts of one datagram on a mesh network, with a reader and a2//! writer for each: the header and its flag bits, the byte that says what the3//! payload is for, the digest that names the packet, the two shapes of the4//! signed reply that says a packet arrived, and the payloads that open an5//! encrypted session. That network is Reticulum, in which nodes find each other6//! by broadcasting signed announcements and reach each other over any medium7//! that moves bytes.8//!9//! Two programs that have never met have to agree on every byte of a 500-byte10//! datagram, down to the order of the bits inside its first byte. The code that11//! reads those bytes runs where memory is fixed before the program starts, so12//! it works in buffers its caller owns and hands back slices of them. One13//! packet needs one name that both ends and every node between them compute the14//! same way, because a signed reply travels back naming the packet it answers.15//!16//! The bytes a device hands over are whatever the wire delivered, so a reader17//! settles every length question before it indexes into them. A packet changes18//! as it travels, because the hop count rises at every node and a node carrying19//! it for someone else inserts sixteen bytes of its own ahead of the address. A20//! field can arrive holding a value this release has no name for, and21//! discarding it would break a peer running a newer build.22//!23//! The subtree follows Reticulum 1.5.0, the reference implementation, pinned to24//! one upstream commit by the package README and the generated conformance25//! corpus. What it takes from the reference is the field order, the bit26//! positions, and the length rule of each layout, and each declaration names27//! the reference file and line range it follows. The package generates byte28//! vectors from that release and replays them in tests, so each of those claims29//! is checkable from this tree.30//!31//! Reading and writing both work in a slice the caller supplies and return a32//! slice of it, so this code calls no allocator. The 32-byte SHA-256 digest33//! that names a packet (*packet hash*) covers the low four bits of the first34//! byte and everything from the address onward, which leaves out the hop count35//! and the sixteen bytes a carrying node inserts, so the name holds still as36//! the packet crosses the mesh. Each enum here names every bit pattern its37//! field can hold, and the header's last byte, which says what the payload is38//! for (*context byte*), carries an unnamed value through a decode and an39//! encode unchanged. The subtree names its pieces: the flag bits, the context40//! byte, the packet hash, the header, the proof payloads, and the link41//! payloads.42//!43//! - *proof*: a packet carrying a signature over an earlier packet's hash, sent44//!   back so the sender learns the packet arrived.45//! - *link*: an encrypted session between two endpoints, named by a 16-byte46//!   link id that both ends derive from the request packet.4748pub const context = @import("context.zig");49pub const flags = @import("flags.zig");50pub const hash = @import("hash.zig");51pub const header = @import("header.zig");52pub const link = @import("link.zig");53pub const proof = @import("proof.zig");5455pub const Context = context.Context;56pub const Flags = flags.Flags;57pub const HeaderType = flags.HeaderType;58pub const TransportType = flags.TransportType;59pub const DestinationType = flags.DestinationType;60pub const PacketType = flags.PacketType;6162pub const Packet = header.Packet;63pub const DecodeError = header.DecodeError;64pub const EncodeError = header.EncodeError;65pub const decode = header.decode;66pub const encode = header.encode;67pub const encodedLength = header.encodedLength;68pub const headerLength = header.headerLength;69pub const header_one_bytes = header.header_one_bytes;70pub const header_two_bytes = header.header_two_bytes;71pub const mtu = header.mtu;72pub const pathfinder_hops = header.pathfinder_hops;73pub const truncated_hash_bytes = header.truncated_hash_bytes;