rns_core/transport/
mod.rs

1pub mod announce_proc;
2pub mod announce_queue;
3pub mod announce_verify_queue;
4pub mod dedup;
5pub mod inbound;
6pub mod ingress_control;
7pub mod jobs;
8pub mod outbound;
9pub mod path_requests;
10pub mod pathfinder;
11pub mod persistence;
12pub mod queries;
13pub mod rate_limit;
14pub mod retention;
15pub mod tables;
16pub mod tunnel;
17pub mod types;
18
19use alloc::collections::{BTreeMap, BTreeSet, VecDeque};
20use alloc::string::String;
21use alloc::vec::Vec;
22use core::mem::size_of;
23
24use rns_crypto::Rng;
25
26use crate::announce::AnnounceData;
27use crate::constants;
28use crate::hash;
29use crate::packet::RawPacket;
30
31use self::announce_proc::compute_path_expires;
32use self::announce_queue::AnnounceQueues;
33use self::announce_verify_queue::{AnnounceVerifyKey, AnnounceVerifyQueue, PendingAnnounce};
34use self::dedup::{AnnounceSignatureCache, PacketHashlist};
35use self::inbound::{
36    clamp_forwarded_link_request_mtu, create_link_entry, create_reverse_entry,
37    forward_transport_packet, route_proof_via_reverse, route_via_link_table, LocalHopRewrite,
38};
39use self::ingress_control::IngressControl;
40use self::outbound::{route_outbound_with_options, should_transmit_announce, OutboundRouteOptions};
41use self::pathfinder::{
42    extract_random_blob, timebase_from_random_blob, timebase_from_random_blobs, MultiPathDecision,
43};
44use self::rate_limit::AnnounceRateLimiter;
45use self::tables::{AnnounceEntry, DiscoveryPathRequest, LinkEntry, PathEntry, PathSet};
46use self::tunnel::TunnelTable;
47use self::types::{
48    BlackholeEntry, InterfaceId, InterfaceInfo, PacketBytes, TransportAction, TransportConfig,
49};
50
51pub type PathTableRow = ([u8; 16], f64, [u8; 16], u8, f64, String);
52pub type RateTableRow = ([u8; 16], f64, u32, f64, Vec<f64>);
53/// Parsed LRPROOF data used to rebalance an existing link route.
54pub type LrproofRebalanceCandidate = ([u8; 16], [u8; 16], u8, Vec<u8>);
55
56fn lrproof_hop_mismatch_diagnostic(packet_hops: u8, entry: &LinkEntry) -> String {
57    alloc::format!(
58        "Received link request proof with hop mismatch ({}/{}:{}->{}), not transporting it",
59        packet_hops,
60        entry.remaining_hops,
61        entry.next_hop_interface.0,
62        entry.received_interface.0,
63    )
64}
65
66fn link_route_hops_match(
67    packet_hops: u8,
68    entry: &LinkEntry,
69    receiving_interface: InterfaceId,
70) -> bool {
71    if entry.next_hop_interface == entry.received_interface {
72        packet_hops == entry.remaining_hops || packet_hops == entry.taken_hops
73    } else if receiving_interface == entry.next_hop_interface {
74        packet_hops == entry.remaining_hops
75    } else if receiving_interface == entry.received_interface {
76        packet_hops == entry.taken_hops
77    } else {
78        // The routing failure is the interface, not a hop mismatch.
79        true
80    }
81}
82
83#[derive(Debug, Clone, Copy, PartialEq, Default)]
84pub struct RxMetadata {
85    pub rssi: Option<i16>,
86    pub snr: Option<f32>,
87}
88
89#[derive(Debug, Clone, Copy, PartialEq)]
90pub struct InboundFrame<'a> {
91    pub raw: &'a [u8],
92    pub iface: InterfaceId,
93    pub now: f64,
94    pub rx: RxMetadata,
95}
96
97impl<'a> InboundFrame<'a> {
98    pub fn new(raw: &'a [u8], iface: InterfaceId, now: f64) -> Self {
99        Self {
100            raw,
101            iface,
102            now,
103            rx: RxMetadata::default(),
104        }
105    }
106
107    pub fn with_rx(mut self, rx: RxMetadata) -> Self {
108        self.rx = rx;
109        self
110    }
111}
112
113/// A syntactically decoded packet. Routing/admission is rechecked on every use.
114/// Fields are read-only so cached hashes cannot diverge from the parsed bytes.
115pub struct DecodedPacket {
116    packet: RawPacket,
117    /// Set by [`TransportEngine::decode_inbound`] for link traffic it only
118    /// forwards; `packet.packet_hash` is then zeroed until the engine needs it.
119    hash_deferred: bool,
120}
121
122impl DecodedPacket {
123    pub fn unpack(raw: &[u8]) -> Result<Self, crate::packet::PacketError> {
124        RawPacket::unpack(raw).map(Self::hashed)
125    }
126
127    /// Decode wire bytes the caller owns without copying them.
128    pub fn unpack_owned(raw: Vec<u8>) -> Result<Self, crate::packet::PacketError> {
129        RawPacket::unpack_owned(raw).map(Self::hashed)
130    }
131
132    fn hashed(packet: RawPacket) -> Self {
133        Self {
134            packet,
135            hash_deferred: false,
136        }
137    }
138
139    /// The decoded fields. Its `packet_hash` is zeroed when hashing was
140    /// deferred; read the hash through [`DecodedPacket::packet_hash`].
141    pub fn packet(&self) -> &RawPacket {
142        &self.packet
143    }
144
145    /// The packet hash, unless [`TransportEngine::decode_inbound`] deferred it.
146    pub fn packet_hash(&self) -> Option<&[u8; 32]> {
147        (!self.hash_deferred).then_some(&self.packet.packet_hash)
148    }
149}
150
151/// Decoded bytes plus the current receive context; no admission decision cached.
152pub struct DecodedInboundFrame {
153    pub decoded: DecodedPacket,
154    pub iface: InterfaceId,
155    pub now: f64,
156    pub rx: RxMetadata,
157}
158
159struct InboundPacketCtx {
160    packet: RawPacket,
161    /// `packet.packet_hash` is zeroed: the packet is link traffic that is
162    /// only forwarded, which never reads it.
163    hash_deferred: bool,
164    original_raw: Option<Vec<u8>>,
165    iface: InterfaceId,
166    now: f64,
167    from_local_client: bool,
168}
169
170struct VerifiedAnnounceCtx<'a> {
171    packet: &'a RawPacket,
172    original_raw: &'a [u8],
173    iface: InterfaceId,
174    now: f64,
175    validated: crate::announce::ValidatedAnnounce,
176    received_from: [u8; 16],
177    random_blob: [u8; 10],
178    announce_emitted: u64,
179}
180
181struct TickCtx<'a> {
182    now: f64,
183    rng: &'a mut dyn Rng,
184    actions: Vec<TransportAction>,
185}
186
187/// Validated, uniquely tagged path request awaiting ingress accounting.
188///
189/// This two-phase token is intended for the network driver; applications
190/// should use [`TransportEngine::handle_path_request`] instead.
191#[doc(hidden)]
192pub struct AcceptedPathRequest {
193    tag: [u8; 16],
194    tag_len: usize,
195    interface_id: InterfaceId,
196    now: f64,
197    destination_hash: [u8; 16],
198    already_in_flight: bool,
199}
200
201/// The core transport/routing engine.
202///
203/// Maintains routing tables and processes packets without performing any I/O.
204/// Returns `Vec<TransportAction>` that the caller must execute.
205pub struct TransportEngine {
206    config: TransportConfig,
207    path_table: BTreeMap<[u8; 16], PathSet>,
208    announce_table: BTreeMap<[u8; 16], AnnounceEntry>,
209    reverse_table: tables::ReverseTable,
210    link_table: BTreeMap<[u8; 16], LinkEntry>,
211    held_announces: BTreeMap<[u8; 16], AnnounceEntry>,
212    packet_hashlist: PacketHashlist,
213    announce_sig_cache: AnnounceSignatureCache,
214    rate_limiter: AnnounceRateLimiter,
215    path_states: BTreeMap<[u8; 16], u8>,
216    interfaces: BTreeMap<InterfaceId, InterfaceInfo>,
217    interface_hashes: BTreeMap<InterfaceId, [u8; 32]>,
218    local_destinations: BTreeMap<[u8; 16], u8>,
219    blackholed_identities: BTreeMap<[u8; 16], BlackholeEntry>,
220    announce_queues: AnnounceQueues,
221    ingress_control: IngressControl,
222    tunnel_table: TunnelTable,
223    discovery_pr_tags: VecDeque<[u8; 32]>,
224    discovery_pr_tag_set: BTreeSet<[u8; 32]>,
225    path_requests: BTreeMap<[u8; 16], f64>,
226    discovery_path_requests: BTreeMap<[u8; 16], DiscoveryPathRequest>,
227    discovery_path_request_deadlines: BTreeMap<[u8; 16], f64>,
228    /// Path requests for destinations behind a local client, by destination:
229    /// the requesting interface and when it asked (Transport.py
230    /// `pending_local_path_requests`).
231    pending_local_path_requests: BTreeMap<[u8; 16], (InterfaceId, f64)>,
232    path_destination_cap_evict_count: usize,
233    // Job timing
234    announces_last_checked: f64,
235    tables_last_culled: f64,
236}
237
238mod engine_state;
239mod inbound_engine;
240mod maintenance;
241mod outbound_engine;
242
243#[cfg(test)]
244mod tests;
rns_core/transport/mod.rs

rns_core/transport/
mod.rs
