Files
fips/src/node/tests/discovery.rs
T
Johnathan Corgan 6011d233c1 discovery: keep tighter path_mtu when applying a LookupResponse
An originator handling a LookupResponse unconditionally overwrote the
cached path_mtu_lookup entry, so a looser (larger) estimate in a later
response could clobber a tighter value already learned from a reactive
MtuExceeded or PathMtuNotification. Read-and-compare before writing and
keep the minimum, so a looser discovery estimate no longer loosens the
clamp. Add a regression test.
2026-07-12 16:29:01 +00:00

1261 lines
47 KiB
Rust

//! Discovery protocol tests: LookupRequest and LookupResponse.
//!
//! Unit tests for handler logic (dedup, TTL, response caching) and
//! integration tests for multi-node forwarding and reverse-path
//! response routing.
use super::*;
use crate::node::RecentRequest;
use crate::protocol::{LookupRequest, LookupResponse};
use crate::tree::TreeCoordinate;
use spanning_tree::{
cleanup_nodes, generate_random_edges, lock_large_network_test, process_available_packets,
run_tree_test, verify_tree_convergence,
};
// ============================================================================
// Unit Tests — LookupRequest Handler
// ============================================================================
#[tokio::test]
async fn test_request_decode_error() {
let mut node = make_node();
let from = make_node_addr(0xAA);
// Too-short payload: should log error and return without panic
node.handle_lookup_request(&from, &[0x00; 5]).await;
assert!(node.recent_requests.is_empty());
}
#[tokio::test]
async fn test_request_dedup() {
let mut node = make_node();
let from = make_node_addr(0xAA);
let target = make_node_addr(0xBB);
let origin = make_node_addr(0xCC);
let coords = TreeCoordinate::from_addrs(vec![origin, make_node_addr(0)]).unwrap();
let request = LookupRequest::new(999, target, origin, coords, 5, 0);
let payload = &request.encode()[1..]; // skip msg_type byte
// First request: accepted
node.handle_lookup_request(&from, payload).await;
assert_eq!(node.recent_requests.len(), 1);
// Duplicate request: dropped
node.handle_lookup_request(&from, payload).await;
assert_eq!(node.recent_requests.len(), 1);
}
#[tokio::test]
async fn test_request_target_is_self() {
let mut node = make_node();
let from = make_node_addr(0xAA);
let origin = make_node_addr(0xCC);
let my_addr = *node.node_addr();
let coords = TreeCoordinate::from_addrs(vec![origin, make_node_addr(0)]).unwrap();
// Request targeting us
let request = LookupRequest::new(777, my_addr, origin, coords, 5, 0);
let payload = &request.encode()[1..];
// Should succeed without panic (response send will fail silently
// since we have no peers to route toward origin)
node.handle_lookup_request(&from, payload).await;
assert!(node.recent_requests.contains_key(&777));
}
#[tokio::test]
async fn test_request_ttl_zero_not_forwarded() {
let mut node = make_node();
let from = make_node_addr(0xAA);
let target = make_node_addr(0xBB);
let origin = make_node_addr(0xCC);
let coords = TreeCoordinate::from_addrs(vec![origin, make_node_addr(0)]).unwrap();
let request = LookupRequest::new(666, target, origin, coords, 0, 0);
let payload = &request.encode()[1..];
node.handle_lookup_request(&from, payload).await;
// Request recorded, but not forwarded (TTL=0, and no peers anyway)
assert!(node.recent_requests.contains_key(&666));
}
// ============================================================================
// Unit Tests — LookupResponse Handler
// ============================================================================
#[tokio::test]
async fn test_response_decode_error() {
let mut node = make_node();
let from = make_node_addr(0xAA);
node.handle_lookup_response(&from, &[0x00; 10]).await;
// No panic, no route cached
assert!(node.coord_cache().is_empty());
}
#[tokio::test]
async fn test_response_originator_caches_route() {
let mut node = make_node();
let from = make_node_addr(0xAA);
// Use the target identity's actual node_addr for consistency
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
// Register target identity in cache so verification can find it
node.register_identity(target, target_identity.pubkey_full());
// Create a valid response with a real proof signature (includes coords)
let proof_data = LookupResponse::proof_bytes(555, &target, &coords);
let proof = target_identity.sign(&proof_data);
let response = LookupResponse::new(555, target, coords.clone(), proof);
let payload = &response.encode()[1..]; // skip msg_type
// No entry in recent_requests for 555 → we're the originator
assert!(!node.recent_requests.contains_key(&555));
node.handle_lookup_response(&from, payload).await;
// Route should be cached in coord_cache
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(node.coord_cache().contains(&target, now_ms));
assert_eq!(node.coord_cache().get(&target, now_ms).unwrap(), &coords);
}
#[tokio::test]
async fn test_response_transit_needs_recent_request() {
let mut node = make_node();
let from = make_node_addr(0xAA);
let target = make_node_addr(0xBB);
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
// Transit nodes don't verify proofs, so any valid signature suffices
let proof_data = LookupResponse::proof_bytes(444, &target, &coords);
let target_identity = Identity::generate();
let proof = target_identity.sign(&proof_data);
let response = LookupResponse::new(444, target, coords, proof);
let payload = &response.encode()[1..];
// Simulate being a transit node: record a recent_request for this ID
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.unwrap()
.as_millis() as u64;
node.recent_requests
.insert(444, RecentRequest::new(make_node_addr(0xDD), now_ms));
// Handle response — should try to reverse-path forward to 0xDD
// (will fail silently since 0xDD is not an actual peer)
node.handle_lookup_response(&from, payload).await;
// Should NOT cache in coord_cache (we're transit, not originator)
let now_ms2 = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(!node.coord_cache().contains(&target, now_ms2));
}
// ============================================================================
// Unit Tests — LookupResponse Proof Verification
// ============================================================================
#[tokio::test]
async fn test_response_proof_verification_success() {
// Verify that a properly signed response is accepted and cached
// when the origin has the target's pubkey in identity_cache.
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
// Register target in identity_cache
node.register_identity(target, target_identity.pubkey_full());
// Sign with correct proof_bytes (including coords)
let proof_data = LookupResponse::proof_bytes(700, &target, &coords);
let proof = target_identity.sign(&proof_data);
let response = LookupResponse::new(700, target, coords.clone(), proof);
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
node.coord_cache().contains(&target, now_ms),
"Valid proof should result in cached coords"
);
assert_eq!(node.coord_cache().get(&target, now_ms).unwrap(), &coords);
}
#[tokio::test]
async fn test_response_proof_verification_failure() {
// Verify that a response with a bad signature is discarded.
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
// Register target in identity_cache
node.register_identity(target, target_identity.pubkey_full());
// Sign with a DIFFERENT identity (wrong key)
let wrong_identity = Identity::generate();
let proof_data = LookupResponse::proof_bytes(701, &target, &coords);
let proof = wrong_identity.sign(&proof_data);
let response = LookupResponse::new(701, target, coords, proof);
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
!node.coord_cache().contains(&target, now_ms),
"Bad signature should NOT result in cached coords"
);
}
#[tokio::test]
async fn test_response_identity_cache_miss() {
// Verify that a response is discarded when the origin lacks the
// target's pubkey in identity_cache (e.g., XK responder before msg3).
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
// Do NOT register target in identity_cache
let proof_data = LookupResponse::proof_bytes(702, &target, &coords);
let proof = target_identity.sign(&proof_data);
let response = LookupResponse::new(702, target, coords, proof);
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
!node.coord_cache().contains(&target, now_ms),
"identity_cache miss should discard the response"
);
}
#[tokio::test]
async fn test_response_coord_substitution_detected() {
// Verify that if the proof was signed with correct coords but
// different coords are placed in the response, verification fails.
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let real_coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
let fake_coords = TreeCoordinate::from_addrs(vec![target, make_node_addr(0xEE), root]).unwrap();
// Register target in identity_cache
node.register_identity(target, target_identity.pubkey_full());
// Sign proof with real coords
let proof_data = LookupResponse::proof_bytes(703, &target, &real_coords);
let proof = target_identity.sign(&proof_data);
// But construct the response with FAKE coords
let response = LookupResponse::new(703, target, fake_coords, proof);
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
!node.coord_cache().contains(&target, now_ms),
"Substituted coords should be detected and response discarded"
);
}
// ============================================================================
// Unit Tests — RecentRequest Expiry
// ============================================================================
#[tokio::test]
async fn test_recent_request_expiry() {
let mut node = make_node();
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.unwrap()
.as_millis() as u64;
// Insert an old request (11 seconds ago)
node.recent_requests
.insert(123, RecentRequest::new(make_node_addr(1), now_ms - 11_000));
// Insert a recent request
node.recent_requests
.insert(456, RecentRequest::new(make_node_addr(2), now_ms));
assert_eq!(node.recent_requests.len(), 2);
// Trigger purge via a new lookup request
let target = make_node_addr(0xBB);
let origin = make_node_addr(0xCC);
let coords = TreeCoordinate::from_addrs(vec![origin, make_node_addr(0)]).unwrap();
let request = LookupRequest::new(789, target, origin, coords, 3, 0);
let payload = &request.encode()[1..];
node.handle_lookup_request(&make_node_addr(0xAA), payload)
.await;
// Old entry (123) should be purged, recent entry (456) and new entry (789) kept
assert!(!node.recent_requests.contains_key(&123));
assert!(node.recent_requests.contains_key(&456));
assert!(node.recent_requests.contains_key(&789));
}
// ============================================================================
// Integration Tests — Multi-Node Forwarding
// ============================================================================
#[tokio::test]
async fn test_request_forwarding_two_node() {
// Set up a two-node topology: node0 — node1
// Send a LookupRequest from node0 targeting node1's address.
// Node1 should receive the forwarded request.
let edges = vec![(0, 1)];
let mut nodes = run_tree_test(2, &edges, false).await;
let node0_addr = *nodes[0].node.node_addr();
let target = *nodes[1].node.node_addr(); // target node1 (in bloom filters)
let root = make_node_addr(0);
let coords = TreeCoordinate::from_addrs(vec![node0_addr, root]).unwrap();
let request = LookupRequest::new(42, target, node0_addr, coords, 5, 0);
let payload = &request.encode()[1..];
// Handle on node0 as if we received it from outside
nodes[0]
.node
.handle_lookup_request(&node0_addr, payload)
.await;
// Process packets — node1 should receive the forwarded request
tokio::time::sleep(Duration::from_millis(50)).await;
let count = process_available_packets(&mut nodes).await;
assert!(
count > 0,
"Expected forwarded LookupRequest to arrive at node 1"
);
// Node1 should have recorded the request
assert!(
nodes[1].node.recent_requests.contains_key(&42),
"Node 1 should have recorded the forwarded request"
);
cleanup_nodes(&mut nodes).await;
}
#[tokio::test]
async fn test_request_target_found_generates_response() {
// Set up a two-node topology: node0 — node1
// Node0 initiates a lookup targeting node1.
// Node1 receives, detects it's the target, generates a LookupResponse.
// Response routes back to node0 which caches the coordinates.
let edges = vec![(0, 1)];
let mut nodes = run_tree_test(2, &edges, false).await;
let node1_addr = *nodes[1].node.node_addr();
// Node0 initiates lookup (doesn't record in recent_requests)
nodes[0].node.initiate_lookup(&node1_addr, 5).await;
// Process packets in rounds to allow request + response
for _ in 0..4 {
tokio::time::sleep(Duration::from_millis(50)).await;
process_available_packets(&mut nodes).await;
}
// Node0 should have cached node1's route (it originated the request)
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
nodes[0].node.coord_cache().contains(&node1_addr, now_ms),
"Node 0 should have cached node 1's route from LookupResponse"
);
cleanup_nodes(&mut nodes).await;
}
#[tokio::test]
async fn test_request_three_node_chain() {
// Topology: node0 — node1 — node2
// Node0 initiates a lookup targeting node2.
// Request should propagate: node0 → node1 → node2.
// Node2 generates response, reverse-path: node2 → node1 → node0.
let edges = vec![(0, 1), (1, 2)];
let mut nodes = run_tree_test(3, &edges, false).await;
let node2_addr = *nodes[2].node.node_addr();
let node2_pubkey = nodes[2].node.identity().pubkey_full();
// Pre-populate node0's identity_cache with node2's identity
// (in production, DNS resolution or prior handshake would do this)
nodes[0].node.register_identity(node2_addr, node2_pubkey);
// Node0 initiates lookup (doesn't record in recent_requests)
nodes[0].node.initiate_lookup(&node2_addr, 8).await;
// Process packets in rounds to allow multi-hop propagation + response
// Chain: node0→node1→node2 (request), node2→node1→node0 (response)
for _ in 0..10 {
tokio::time::sleep(Duration::from_millis(100)).await;
process_available_packets(&mut nodes).await;
}
// Node1 should have been a transit node (has the request_id in recent_requests)
assert!(
!nodes[1].node.recent_requests.is_empty(),
"Node 1 should have recorded the forwarded request"
);
// Node2 should have received the request (it's the target)
assert!(
!nodes[2].node.recent_requests.is_empty(),
"Node 2 should have received the request"
);
// Node0 should have cached node2's route
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
nodes[0].node.coord_cache().contains(&node2_addr, now_ms),
"Node 0 should have cached node 2's route through 3-node chain"
);
cleanup_nodes(&mut nodes).await;
}
#[tokio::test]
async fn test_request_dedup_convergent_paths() {
// Topology: triangle (node0 — node1, node0 — node2, node1 — node2)
// A request from node0 targeting node2 may reach it via two paths
// depending on bloom filter state. If both paths deliver the request,
// the second arrival at node2 should be deduped.
let edges = vec![(0, 1), (0, 2), (1, 2)];
let mut nodes = run_tree_test(3, &edges, false).await;
let node0_addr = *nodes[0].node.node_addr();
let target = *nodes[2].node.node_addr(); // target node2 (in bloom filters)
let root = make_node_addr(0);
let coords = TreeCoordinate::from_addrs(vec![node0_addr, root]).unwrap();
let request = LookupRequest::new(300, target, node0_addr, coords, 5, 0);
let payload = &request.encode()[1..];
// Node0 handles the request (forwards to peers whose bloom filter
// contains node2 — bloom-guided, not flooding)
nodes[0]
.node
.handle_lookup_request(&node0_addr, payload)
.await;
// Process several rounds
for _ in 0..5 {
tokio::time::sleep(Duration::from_millis(50)).await;
process_available_packets(&mut nodes).await;
}
// Node2 (the target) must have received the request
assert!(
nodes[2].node.recent_requests.contains_key(&300),
"Node 2 (target) should have received the request"
);
// If node1 also received and forwarded it, node2 would have seen a
// duplicate — verify dedup counter reflects convergent arrivals.
// With bloom-guided routing, node1 may or may not receive the request
// depending on filter state, so we only assert the target received it.
cleanup_nodes(&mut nodes).await;
}
// ============================================================================
// Integration Tests — 100-Node Discovery
// ============================================================================
#[tokio::test]
#[ignore] // Long-running (~2 min): run explicitly with --ignored
async fn test_discovery_100_nodes() {
let _guard = lock_large_network_test().await;
// Set up a 100-node random topology (same seed as other 100-node tests).
// Each node initiates lookups to a sample of other nodes in batches,
// processing packets between batches to avoid flooding the network.
const NUM_NODES: usize = 100;
const TARGET_EDGES: usize = 250;
const SEED: u64 = 42;
const TTL: u8 = 20; // must exceed tree diameter (can reach 17+ hops)
let edges = generate_random_edges(NUM_NODES, TARGET_EDGES, SEED);
let mut nodes = run_tree_test(NUM_NODES, &edges, false).await;
verify_tree_convergence(&nodes);
// Disable forward rate limiting: in this test all 100 nodes look up
// the same 10 targets in <1s wall time. The 2s per-target rate limit
// would suppress nearly all transit forwarding.
for tn in nodes.iter_mut() {
tn.node.disable_discovery_forward_rate_limit();
}
// Collect all node addresses and public keys for lookup targets
let all_addrs: Vec<NodeAddr> = nodes.iter().map(|tn| *tn.node.node_addr()).collect();
let all_pubkeys: Vec<secp256k1::PublicKey> = nodes
.iter()
.map(|tn| tn.node.identity().pubkey_full())
.collect();
// Pre-populate identity caches: each source needs the target's pubkey
// for proof verification. In production, DNS resolution populates this
// before lookups are initiated.
for (src, node) in nodes.iter_mut().enumerate() {
for dst in (0..NUM_NODES).step_by(10) {
if src == dst {
continue;
}
node.node
.register_identity(all_addrs[dst], all_pubkeys[dst]);
}
}
// Each node looks up every 10th other node (~10 targets per node).
// Build the full list of (src, dst) pairs.
let mut lookup_pairs: Vec<(usize, usize)> = Vec::new();
for src in 0..NUM_NODES {
for dst in (0..NUM_NODES).step_by(10) {
if src == dst {
continue;
}
lookup_pairs.push((src, dst));
}
}
let total_lookups = lookup_pairs.len();
// Process one source node at a time. Each node initiates ~10 lookups,
// which route through the tree via bloom filters. We drain until
// quiescent before moving to the next node.
for src in 0..NUM_NODES {
// Initiate all lookups for this source node
let mut initiated = false;
for &(s, dst) in &lookup_pairs {
if s == src {
nodes[src].node.initiate_lookup(&all_addrs[dst], TTL).await;
initiated = true;
}
}
if !initiated {
continue;
}
// Drain packets until quiescent. With single-path tree routing,
// a packet forwarded by node X may land in node Y's queue where
// Y < X in iteration order, causing a zero-count round even though
// packets are in flight. Use a higher idle threshold to handle this.
let mut idle_rounds = 0;
for _ in 0..80 {
tokio::time::sleep(Duration::from_millis(5)).await;
let count = process_available_packets(&mut nodes).await;
if count == 0 {
idle_rounds += 1;
if idle_rounds >= 5 {
break;
}
} else {
idle_rounds = 0;
}
}
}
// Verify: each originator should have the target's coords in coord_cache
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
let mut resolved = 0usize;
let mut failed = 0usize;
let mut failed_pairs: Vec<(usize, usize)> = Vec::new();
for &(src, dst) in &lookup_pairs {
if nodes[src]
.node
.coord_cache()
.contains(&all_addrs[dst], now_ms)
{
resolved += 1;
} else {
failed += 1;
if failed_pairs.len() < 20 {
failed_pairs.push((src, dst));
}
}
}
eprintln!("\n === Discovery 100-Node Test ===",);
eprintln!(
" Lookups: {} | Resolved: {} | Failed: {} | Success rate: {:.1}%",
total_lookups,
resolved,
failed,
resolved as f64 / total_lookups as f64 * 100.0
);
// Report coord_cache stats across all nodes
let total_cached: usize = nodes.iter().map(|tn| tn.node.coord_cache().len()).sum();
let min_cached = nodes
.iter()
.map(|tn| tn.node.coord_cache().len())
.min()
.unwrap();
let max_cached = nodes
.iter()
.map(|tn| tn.node.coord_cache().len())
.max()
.unwrap();
eprintln!(
" Coord cache entries: total={} min={} max={} avg={:.1}",
total_cached,
min_cached,
max_cached,
total_cached as f64 / NUM_NODES as f64
);
// Detailed diagnostics for failures (to aid future debugging)
if !failed_pairs.is_empty() {
eprintln!(
" --- Failure Diagnostics ({} failures) ---",
failed_pairs.len()
);
for &(src, dst) in &failed_pairs {
let src_coords = nodes[src].node.tree_state().my_coords().clone();
let dst_coords = nodes[dst].node.tree_state().my_coords().clone();
let tree_dist = src_coords.distance_to(&dst_coords);
let reverse_cached = nodes[dst]
.node
.coord_cache()
.contains(&all_addrs[src], now_ms);
let src_peers = nodes[src].node.peers.len();
let dst_peers = nodes[dst].node.peers.len();
eprintln!(
" node {} -> node {}: tree_dist={} src_depth={} dst_depth={} \
src_peers={} dst_peers={} reverse_cached={}",
src,
dst,
tree_dist,
src_coords.depth(),
dst_coords.depth(),
src_peers,
dst_peers,
reverse_cached
);
}
}
assert_eq!(
failed, 0,
"All {} lookups should resolve, but {} failed",
total_lookups, failed
);
cleanup_nodes(&mut nodes).await;
}
// ============================================================================
// Integration Tests — MTU Propagation
// ============================================================================
#[tokio::test]
async fn test_response_path_mtu_two_node() {
// Two-node topology: node0 — node1
// Node0 initiates lookup for node1. node1 is the target and generates
// the response: send_lookup_response folds in node1's own outgoing-link
// MTU before sending, so path_mtu reflects the target-edge link
// constraint (the test transport MTU, 1280) even with no transit hops.
// Without that target-edge fold, a 2-node lookup would leave path_mtu
// at u16::MAX since no transit min-fold runs — that's the gap closed
// alongside the configured-peer seed in the B3 follow-up.
let edges = vec![(0, 1)];
let mut nodes = run_tree_test(2, &edges, false).await;
let node1_addr = *nodes[1].node.node_addr();
nodes[0].node.initiate_lookup(&node1_addr, 5).await;
for _ in 0..4 {
tokio::time::sleep(Duration::from_millis(50)).await;
process_available_packets(&mut nodes).await;
}
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
nodes[0].node.coord_cache().contains(&node1_addr, now_ms),
"Node 0 should have cached node 1's route"
);
let entry = nodes[0].node.coord_cache().get_entry(&node1_addr).unwrap();
let path_mtu = entry
.path_mtu()
.expect("path_mtu should be set from discovery");
assert_eq!(
path_mtu, 1280,
"Two-node path_mtu should be the target-edge link MTU (1280 in tests)"
);
cleanup_nodes(&mut nodes).await;
}
#[tokio::test]
async fn test_apply_outgoing_link_mtu_to_response_unknown_peer_noop() {
// When next_hop is not a directly-connected peer (no entry in
// self.peers), apply_outgoing_link_mtu_to_response is a no-op and the
// response's path_mtu is left unchanged. Pins the early-return path.
let node = make_node();
let unknown = make_node_addr(0x99);
let coords = TreeCoordinate::from_addrs(vec![unknown, make_node_addr(0)]).unwrap();
let identity = Identity::generate();
let proof_data = LookupResponse::proof_bytes(1, &unknown, &coords);
let proof = identity.sign(&proof_data);
let mut response = LookupResponse::new(1, unknown, coords, proof);
response.path_mtu = 1500;
node.apply_outgoing_link_mtu_to_response(&mut response, &unknown);
assert_eq!(
response.path_mtu, 1500,
"Unknown next_hop must leave path_mtu untouched"
);
}
#[tokio::test]
async fn test_response_path_mtu_three_node_chain() {
// Topology: node0 — node1 — node2
// Node0 initiates lookup for node2. The response travels node2→node1→node0.
// Node1 is a transit node and applies path_mtu = min(u16::MAX, link_mtu).
// With test transport MTU of 1280, the final path_mtu at node0 should be 1280.
let edges = vec![(0, 1), (1, 2)];
let mut nodes = run_tree_test(3, &edges, false).await;
let node2_addr = *nodes[2].node.node_addr();
let node2_pubkey = nodes[2].node.identity().pubkey_full();
nodes[0].node.register_identity(node2_addr, node2_pubkey);
nodes[0].node.initiate_lookup(&node2_addr, 8).await;
for _ in 0..10 {
tokio::time::sleep(Duration::from_millis(100)).await;
process_available_packets(&mut nodes).await;
}
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(
nodes[0].node.coord_cache().contains(&node2_addr, now_ms),
"Node 0 should have cached node 2's route"
);
// Node1 is transit and applies min(u16::MAX, 1280) = 1280
let entry = nodes[0].node.coord_cache().get_entry(&node2_addr).unwrap();
let path_mtu = entry
.path_mtu()
.expect("path_mtu should be set from discovery");
assert_eq!(
path_mtu, 1280,
"Three-node chain path_mtu should reflect transit node's transport MTU (1280)"
);
cleanup_nodes(&mut nodes).await;
}
// ============================================================================
// Unit Tests — Cache Entry path_mtu
// ============================================================================
#[tokio::test]
async fn test_cache_entry_path_mtu_stored() {
// Verify that insert_with_path_mtu stores the path_mtu in the cache entry
let mut node = make_node();
let target = make_node_addr(0xBB);
let coords = TreeCoordinate::from_addrs(vec![target, make_node_addr(0)]).unwrap();
let now_ms = 1000u64;
node.coord_cache_mut()
.insert_with_path_mtu(target, coords, now_ms, 1280);
let entry = node.coord_cache().get_entry(&target).unwrap();
assert_eq!(entry.path_mtu(), Some(1280));
}
#[tokio::test]
async fn test_cache_entry_no_path_mtu_from_regular_insert() {
// Verify that regular insert() does not set path_mtu
let mut node = make_node();
let target = make_node_addr(0xBB);
let coords = TreeCoordinate::from_addrs(vec![target, make_node_addr(0)]).unwrap();
let now_ms = 1000u64;
node.coord_cache_mut().insert(target, coords, now_ms);
let entry = node.coord_cache().get_entry(&target).unwrap();
assert_eq!(entry.path_mtu(), None);
}
// ============================================================================
// Unit Tests — LookupRequest min_mtu field
// ============================================================================
#[tokio::test]
async fn test_request_min_mtu_preserved_through_encode_decode() {
// Verify min_mtu survives encode/decode in the handler test context
let target = make_node_addr(0xBB);
let origin = make_node_addr(0xCC);
let coords = TreeCoordinate::from_addrs(vec![origin, make_node_addr(0)]).unwrap();
let request = LookupRequest::new(100, target, origin, coords, 5, 1386);
let encoded = request.encode();
let decoded = LookupRequest::decode(&encoded[1..]).unwrap();
assert_eq!(decoded.min_mtu, 1386);
}
// ============================================================================
// Unit Tests — LookupResponse path_mtu in originator handling
// ============================================================================
#[tokio::test]
async fn test_originator_stores_path_mtu_in_cache() {
// Verify that the originator stores path_mtu from the response in coord_cache
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
node.register_identity(target, target_identity.pubkey_full());
let proof_data = LookupResponse::proof_bytes(800, &target, &coords);
let proof = target_identity.sign(&proof_data);
let mut response = LookupResponse::new(800, target, coords.clone(), proof);
// Simulate transit having reduced path_mtu
response.path_mtu = 1280;
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
let now_ms = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_millis() as u64)
.unwrap_or(0);
assert!(node.coord_cache().contains(&target, now_ms));
let entry = node.coord_cache().get_entry(&target).unwrap();
assert_eq!(
entry.path_mtu(),
Some(1280),
"Originator should store path_mtu from LookupResponse in cache"
);
}
#[tokio::test]
async fn test_originator_lookup_response_keeps_tighter_path_mtu_lookup() {
// Regression: a LookupResponse carrying a looser (larger) path_mtu must
// NOT clobber a tighter (smaller) value already in path_mtu_lookup that a
// reactive MtuExceeded or PathMtuNotification learned. Cross-carrier
// keep-tighter: the clamp must never loosen.
let mut node = make_node();
let from = make_node_addr(0xAA);
let target_identity = Identity::generate();
let target = *target_identity.node_addr();
let root = make_node_addr(0xF0);
let coords = TreeCoordinate::from_addrs(vec![target, root]).unwrap();
node.register_identity(target, target_identity.pubkey_full());
// Pre-seed a tighter value, as if a reactive signal already narrowed it.
let target_fips = crate::FipsAddress::from_node_addr(&target);
node.path_mtu_lookup_insert(target_fips, 1280);
let proof_data = LookupResponse::proof_bytes(800, &target, &coords);
let proof = target_identity.sign(&proof_data);
let mut response = LookupResponse::new(800, target, coords.clone(), proof);
// Looser discovery estimate that must be rejected in favor of the tighter
// existing entry.
response.path_mtu = 1500;
let payload = &response.encode()[1..];
node.handle_lookup_response(&from, payload).await;
assert_eq!(
node.path_mtu_lookup_get(&target_fips),
Some(1280),
"LookupResponse must not loosen a tighter existing path_mtu_lookup value"
);
}
// ============================================================================
// Open-Discovery Sweep — cache-injection unit test
// ============================================================================
/// Pin the iterate-filter-queue contract of `run_open_discovery_sweep`.
///
/// Builds a `Node` with `nostr.policy = Open` and an empty peer list,
/// then injects three cached adverts into a test `NostrDiscovery` and
/// asserts the sweep:
/// - queues a retry for an eligible (unknown, not-self) advert,
/// - skips the advert whose author is our own node identity, and
/// - skips the advert whose author is an already-connected peer.
///
/// Uses `NostrDiscovery::new_for_test()` and `insert_advert_for_test()`
/// (both `#[cfg(test)]`-gated test escape hatches in
/// `src/discovery/nostr/runtime.rs`) to populate the cache without
/// requiring live relay subscriptions.
#[tokio::test]
async fn test_open_discovery_sweep_queues_eligible_skips_filtered() {
use crate::config::NostrDiscoveryPolicy;
use crate::discovery::nostr::{NostrDiscovery, OverlayEndpointAdvert, OverlayTransportKind};
use crate::peer::ActivePeer;
use crate::transport::LinkId;
use std::sync::Arc;
// Build node with open-discovery enabled.
let mut config = crate::Config::new();
config.node.discovery.nostr.enabled = true;
config.node.discovery.nostr.policy = NostrDiscoveryPolicy::Open;
let mut node = crate::Node::new(config).unwrap();
// Identity of an already-connected peer; insert into node.peers
// so the sweep's `self.peers.contains_key(&node_addr)` filter fires.
let connected_identity = crate::Identity::generate();
let connected_npub = crate::encode_npub(&connected_identity.pubkey());
let connected_node_addr = *connected_identity.node_addr();
let connected_peer_identity = crate::PeerIdentity::from_pubkey(connected_identity.pubkey());
node.peers.insert(
connected_node_addr,
ActivePeer::new(connected_peer_identity, LinkId::new(1), 1_000),
);
// Eligible peer: fresh identity not in node.peers / retry_pending.
let eligible_identity = crate::Identity::generate();
let eligible_npub = crate::encode_npub(&eligible_identity.pubkey());
let eligible_node_addr = *eligible_identity.node_addr();
// Self filter: advert authored by node's own identity.
let self_npub = crate::encode_npub(&node.identity().pubkey());
let self_node_addr = *node.identity().node_addr();
// Build a NostrDiscovery test instance and inject the three adverts.
let bootstrap = Arc::new(NostrDiscovery::new_for_test());
let endpoint = OverlayEndpointAdvert {
transport: OverlayTransportKind::Udp,
addr: "203.0.113.7:2121".to_string(),
};
let now_secs = std::time::SystemTime::now()
.duration_since(std::time::UNIX_EPOCH)
.map(|d| d.as_secs())
.unwrap_or(0);
for npub in [&eligible_npub, &connected_npub, &self_npub] {
let advert =
NostrDiscovery::cached_advert_for_test(npub.clone(), endpoint.clone(), now_secs);
bootstrap.insert_advert_for_test(npub.clone(), advert).await;
}
// Run the sweep.
node.run_open_discovery_sweep(&bootstrap, Some(3_600), "test")
.await;
// Eligible peer was queued.
assert!(
node.retry_pending.contains_key(&eligible_node_addr),
"eligible advert should be queued for retry"
);
let queued = node.retry_pending.get(&eligible_node_addr).unwrap();
assert_eq!(queued.peer_config.npub, eligible_npub);
// Connected-peer skip filter held.
assert!(
!node.retry_pending.contains_key(&connected_node_addr),
"advert for already-connected peer must not be queued"
);
// Self skip filter held.
assert!(
!node.retry_pending.contains_key(&self_node_addr),
"advert authored by own node must not be queued"
);
// Exactly one queued entry from the three injected adverts.
assert_eq!(node.retry_pending.len(), 1);
}
// ============================================================================
// Per-Attempt Timeout State Machine — IF-3-A
// ============================================================================
/// Pin the per-attempt timeout sequence in `check_pending_lookups`.
///
/// Drives the state machine deterministically through the default
/// `node.discovery.attempt_timeouts_secs = [1, 2, 4, 8]` sequence.
/// Asserts:
/// 1. **Sequence timing** — retries fire at the cumulative deadlines
/// (t=1100ms, 3100ms, 7100ms) and unreachable at t=15100ms.
/// 2. **Fresh `initiate_lookup` per attempt** — `req_initiated` counter
/// increments by exactly one on each retry. The actual `request_id`
/// is generated by `LookupRequest::generate(...)` via `rand::random()`
/// inside `initiate_lookup` and is not stored on the originator
/// side, so per-attempt freshness is verified indirectly: each
/// `req_initiated` increment corresponds to one fresh
/// `LookupRequest::generate` call.
/// 3. **Final-timeout state transitions** — `pending_lookups` entry is
/// removed, `discovery.resp_timed_out` counter ticks, queued packet
/// is drained, and an ICMPv6 Destination Unreachable frame is
/// emitted via the TUN sender.
///
/// Skipped: direct request_id capture (originator does not record its
/// own request_ids; would require production instrumentation). The
/// `req_initiated` counter is the strongest cleanly-observable signal
/// that `initiate_lookup` ran fresh on each attempt.
#[tokio::test]
async fn test_check_pending_lookups_default_sequence_unreachable() {
use crate::bloom::BloomFilter;
use crate::node::handlers::discovery::PendingLookup;
use crate::peer::ActivePeer;
use crate::transport::LinkId;
use std::sync::mpsc;
let mut node = make_node();
// Default attempt_timeouts_secs is [1, 2, 4, 8]. Confirm so the test
// cannot silently drift if the default changes.
assert_eq!(
node.config().node.discovery.attempt_timeouts_secs,
vec![1, 2, 4, 8],
"test pins the [1,2,4,8] default; update the test if the default changes"
);
// Inject a TUN sender so `send_icmpv6_dest_unreachable` is observable.
let (tun_tx, tun_rx) = mpsc::channel::<Vec<u8>>();
node.tun_tx = Some(tun_tx);
// Build a target identity (the unreachable destination).
let target_identity = Identity::generate();
let target_addr = *target_identity.node_addr();
// Build a tree-peer that:
// - has the target in its inbound bloom filter (so `may_reach` is true),
// - declares us as its parent (so `is_tree_peer` returns true).
// The peer has no Noise session, so `send_encrypted_link_message` will
// fail at the wire-send step — but `initiate_lookup` already incremented
// `req_initiated` and the failure is logged at `debug!`. The state-
// machine bookkeeping we want to test runs to completion either way.
let peer_identity_full = Identity::generate();
let peer_addr = *peer_identity_full.node_addr();
let peer_identity = crate::PeerIdentity::from_pubkey(peer_identity_full.pubkey());
let mut peer = ActivePeer::new(peer_identity, LinkId::new(1), 0);
let mut bloom = BloomFilter::new();
bloom.insert(&target_addr);
peer.update_filter(bloom, 1, 0);
node.peers.insert(peer_addr, peer);
// Make the peer a tree-peer: install a peer declaration that names us
// as its parent. `is_tree_peer` checks both directions — the child
// direction (peer.parent_id == self.node_addr) is what we exercise.
let our_addr = *node.node_addr();
let peer_decl = crate::tree::ParentDeclaration::new(peer_addr, our_addr, 1, 0);
let peer_coords = TreeCoordinate::from_addrs(vec![peer_addr, our_addr]).unwrap();
node.tree_state_mut().update_peer(peer_decl, peer_coords);
assert!(node.is_tree_peer(&peer_addr), "peer must be a tree peer");
// Queue an IPv6 packet for the target so the final-timeout drop +
// ICMPv6 emission can be observed. Build a minimal valid IPv6 header
// with a non-multicast, non-unspecified source so
// `should_send_icmp_error` returns true.
let mut ipv6_pkt = vec![0u8; 40];
ipv6_pkt[0] = 0x60; // version 6
ipv6_pkt[6] = 17; // next_header = UDP (not ICMPv6)
ipv6_pkt[7] = 64; // hop limit
// src = fd00::1 (non-multicast, non-unspecified)
ipv6_pkt[8] = 0xfd;
ipv6_pkt[23] = 0x01;
// dst = target's IPv6 representation (not strictly required, just non-multicast)
let target_ipv6 = crate::FipsAddress::from_node_addr(&target_addr).to_ipv6();
ipv6_pkt[24..40].copy_from_slice(&target_ipv6.octets());
let mut queue = std::collections::VecDeque::new();
queue.push_back(ipv6_pkt);
node.pending_tun_packets.insert(target_addr, queue);
// Inject a PendingLookup directly: attempt=1, last_sent_ms=0. This
// mirrors the post-condition of a successful `maybe_initiate_lookup`
// at t=0 without depending on wall-clock-derived `Self::now_ms()`.
node.pending_lookups
.insert(target_addr, PendingLookup::new(0));
let baseline_initiated = node.metrics().discovery.req_initiated.get();
let baseline_timed_out = node.metrics().discovery.resp_timed_out.get();
// --- t = 1100ms: first retry deadline (1*1000) ---
node.check_pending_lookups(1100).await;
{
let entry = node
.pending_lookups
.get(&target_addr)
.expect("still pending");
assert_eq!(entry.attempt, 2, "after retry #1, attempt should be 2");
assert_eq!(entry.last_sent_ms, 1100);
}
assert_eq!(
node.metrics().discovery.req_initiated.get(),
baseline_initiated + 1,
"retry #1 must invoke initiate_lookup exactly once"
);
// --- t = 3100ms: second retry deadline (cumulative 1+2 = 3s) ---
node.check_pending_lookups(3100).await;
{
let entry = node
.pending_lookups
.get(&target_addr)
.expect("still pending");
assert_eq!(entry.attempt, 3, "after retry #2, attempt should be 3");
assert_eq!(entry.last_sent_ms, 3100);
}
assert_eq!(
node.metrics().discovery.req_initiated.get(),
baseline_initiated + 2,
"retry #2 must invoke initiate_lookup exactly once more"
);
// --- t = 7100ms: third retry deadline (cumulative 1+2+4 = 7s) ---
node.check_pending_lookups(7100).await;
{
let entry = node
.pending_lookups
.get(&target_addr)
.expect("still pending");
assert_eq!(entry.attempt, 4, "after retry #3, attempt should be 4");
assert_eq!(entry.last_sent_ms, 7100);
}
assert_eq!(
node.metrics().discovery.req_initiated.get(),
baseline_initiated + 3,
"retry #3 must invoke initiate_lookup exactly once more"
);
// --- Just-before-final: at t=15099ms the 8s window is not yet reached ---
node.check_pending_lookups(15_099).await;
assert!(
node.pending_lookups.contains_key(&target_addr),
"8s window not yet expired: pending_lookup must persist"
);
assert_eq!(
node.metrics().discovery.req_initiated.get(),
baseline_initiated + 3,
"no new attempt before final deadline"
);
assert_eq!(
node.metrics().discovery.resp_timed_out.get(),
baseline_timed_out,
"no timeout before final deadline"
);
// --- t = 15100ms: final deadline (cumulative 1+2+4+8 = 15s) ---
// Drain any TUN frames that may have leaked from earlier steps so the
// post-final-timeout drain observes only the unreachable-emission output.
while tun_rx.try_recv().is_ok() {}
node.check_pending_lookups(15_100).await;
// Pending lookup is dropped.
assert!(
!node.pending_lookups.contains_key(&target_addr),
"final timeout must remove the pending_lookups entry"
);
// resp_timed_out counter ticked.
assert_eq!(
node.metrics().discovery.resp_timed_out.get(),
baseline_timed_out + 1,
"final timeout must increment discovery.resp_timed_out"
);
// No additional initiate_lookup on the timeout step.
assert_eq!(
node.metrics().discovery.req_initiated.get(),
baseline_initiated + 3,
"the final-timeout step must NOT call initiate_lookup"
);
// Queued packet was drained from pending_tun_packets.
assert!(
!node.pending_tun_packets.contains_key(&target_addr),
"queued packets for the unreachable target must be drained"
);
// ICMPv6 Destination Unreachable was emitted to the TUN sender.
let icmp_frame = tun_rx
.try_recv()
.expect("ICMPv6 Destination Unreachable must be emitted on final timeout");
assert!(
icmp_frame.len() >= 48,
"ICMPv6 frame must be at least IPv6 header (40) + ICMPv6 header (8)"
);
assert_eq!(icmp_frame[0] >> 4, 6, "must be IPv6");
assert_eq!(icmp_frame[6], 58, "next_header must be IPPROTO_ICMPV6 (58)");
assert_eq!(icmp_frame[40], 1, "ICMPv6 type 1 = Destination Unreachable");
}