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fuzz: prepare payment failure tracking
Public commit record
78/100 · Adequate
What the developer wrote
Authored by Joost Jager
fuzz: prepare payment failure tracking
Carry each send's minimum final CLTV expiry into payment
registration. Thread PaymentTracker through HTLC message delivery and
separate PaymentFailed from ProbeFailed dispatch.
A later invariant commit uses this context to classify failure roots.
Keeping the plumbing separate reduces its behavioral review even though
the minimum expiry remains temporarily unread.
✓ Descriptive subject✓ Names a concrete action or component✓ Provides detailed explanatory context✓ Mentions testing or verification
What changed, and why it matters
This commit only changes internal fuzz-testing code in rust-lightning. It adds plumbing to track the minimum final CLTV expiry for simulated payments and threads a PaymentTracker through more test helpers. The commit message explicitly says the new value is not yet used and that this is preparation for a later commit. There is no change to production Lightning logic, no fix for a vulnerability, and no security-relevant behavior change.
Recommended action
No security action needed. Treat as a normal test-infrastructure refactor. If reviewing the series, evaluate the later invariant commit that actually consumes min_final_cltv_expiry.
Security signals we found
No strong security signals were identified.
Evidence from the diff
The diff modifies fuzz/src/chanmon_consistency.rs, a fuzzing harness. It extends PendingPayment and NodePayments::add_pending with a min_final_cltv_expiry field, computes that value from route paths, and passes it through send helpers. It also threads &mut PaymentTracker through HTLC message-delivery helpers and splits the PaymentFailed/ProbeFailed event match arms. The commit message states the expiry is ‘temporarily unread’ and that this is ‘plumbing’ for a later invariant commit. No production code is touched.
Changed components
fuzz/src/chanmon_consistency.rsInspect captured patch +71 / −10
diff --git a/fuzz/src/chanmon_consistency.rs b/fuzz/src/chanmon_consistency.rs
index 033279f..5d493d5 100644
--- a/fuzz/src/chanmon_consistency.rs
+++ b/fuzz/src/chanmon_consistency.rs
@@ -1955,6 +1955,7 @@ struct PendingPayment {
payment_id: PaymentId,
payment_hash: PaymentHash,
first_persisted_manager_generation: u64,
+ min_final_cltv_expiry: u32,
}
struct NodePayments {
@@ -1969,7 +1970,7 @@ impl NodePayments {
fn add_pending(
&mut self, payment_id: PaymentId, payment_hash: PaymentHash,
- first_persisted_manager_generation: u64,
+ first_persisted_manager_generation: u64, min_final_cltv_expiry: u32,
) {
assert!(!self.pending.iter().any(|pending| pending.payment_id == payment_id));
assert!(!self.resolved.contains_key(&payment_id));
@@ -1977,6 +1978,7 @@ impl NodePayments {
payment_id,
payment_hash,
first_persisted_manager_generation,
+ min_final_cltv_expiry,
});
}
@@ -2133,15 +2135,33 @@ impl PaymentTracker {
})
}
+ fn route_min_final_cltv_expiry(route: &Route, source_best_block_height: u32) -> u32 {
+ let cur_height = source_best_block_height.saturating_add(1);
+ route
+ .paths
+ .iter()
+ .map(|path| {
+ cur_height.saturating_add(
+ path.hops
+ .last()
+ .expect("payment path should contain at least one hop")
+ .cltv_expiry_delta,
+ )
+ })
+ .min()
+ .expect("payment route should contain at least one path")
+ }
+
fn record_send_result(
&mut self, source_idx: usize, source: &HarnessNode<'_>, payment_id: PaymentId,
- payment_hash: PaymentHash, has_pending_work: bool,
+ payment_hash: PaymentHash, min_final_cltv_expiry: u32, has_pending_work: bool,
) {
let node_payments = &mut self.nodes[source_idx];
node_payments.add_pending(
payment_id,
payment_hash,
source.next_manager_persistence_generation(),
+ min_final_cltv_expiry,
);
if !has_pending_work {
node_payments.resolve_pending(payment_id, None);
@@ -2174,6 +2194,8 @@ impl PaymentTracker {
amt,
);
let route = Self::route_from_payment_paths(&payment_paths, &[dest], route_params);
+ let min_final_cltv_expiry =
+ Self::route_min_final_cltv_expiry(&route, source.current_best_block().height);
let onion = RecipientOnionFields::secret_only(secret, amt);
let res = source.send_payment_with_route(route, hash, onion, id);
let has_pending_work = match res {
@@ -2187,7 +2209,14 @@ impl PaymentTracker {
has_pending_work
},
};
- self.record_send_result(source_idx, source, id, hash, has_pending_work);
+ self.record_send_result(
+ source_idx,
+ source,
+ id,
+ hash,
+ min_final_cltv_expiry,
+ has_pending_work,
+ );
has_pending_work
}
@@ -2227,6 +2256,8 @@ impl PaymentTracker {
amt,
);
let route = Self::route_from_payment_paths(&payment_paths, &[middle, dest], route_params);
+ let min_final_cltv_expiry =
+ Self::route_min_final_cltv_expiry(&route, source.current_best_block().height);
let onion = RecipientOnionFields::secret_only(secret, amt);
let res = source.send_payment_with_route(route, hash, onion, id);
let has_pending_work = match res {
@@ -2241,7 +2272,14 @@ impl PaymentTracker {
has_pending_work
},
};
- self.record_send_result(source_idx, source, id, hash, has_pending_work);
+ self.record_send_result(
+ source_idx,
+ source,
+ id,
+ hash,
+ min_final_cltv_expiry,
+ has_pending_work,
+ );
}
fn send_noret(
@@ -2296,13 +2334,22 @@ impl PaymentTracker {
amt,
);
let route = Self::route_from_payment_paths(&payment_paths, &[dest], route_params);
+ let min_final_cltv_expiry =
+ Self::route_min_final_cltv_expiry(&route, source.current_best_block().height);
let onion = RecipientOnionFields::secret_only(secret, amt);
let res = source.send_payment_with_route(route, hash, onion, id);
let has_pending_work = match res {
Err(_) => false,
Ok(()) => Self::payment_has_pending_work(source, id),
};
- self.record_send_result(source_idx, source, id, hash, has_pending_work);
+ self.record_send_result(
+ source_idx,
+ source,
+ id,
+ hash,
+ min_final_cltv_expiry,
+ has_pending_work,
+ );
}
// MPP payment via hop - splits payment across multiple channels on either or both hops
@@ -2374,13 +2421,22 @@ impl PaymentTracker {
amt,
);
let route = Self::route_from_payment_paths(&payment_paths, &[middle, dest], route_params);
+ let min_final_cltv_expiry =
+ Self::route_min_final_cltv_expiry(&route, source.current_best_block().height);
let onion = RecipientOnionFields::secret_only(secret, amt);
let res = source.send_payment_with_route(route, hash, onion, id);
let has_pending_work = match res {
Err(_) => false,
Ok(()) => Self::payment_has_pending_work(source, id),
};
- self.record_send_result(source_idx, source, id, hash, has_pending_work);
+ self.record_send_result(
+ source_idx,
+ source,
+ id,
+ hash,
+ min_final_cltv_expiry,
+ has_pending_work,
+ );
}
fn claim_payment(&mut self, node: &HarnessNode<'_>, payment_hash: PaymentHash, fail: bool) {
@@ -3067,7 +3123,7 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
fn handle_update_htlcs_event<Out: Output + MaybeSend + MaybeSync>(
node_idx: usize, source_node_id: PublicKey, node_id: PublicKey, channel_id: ChannelId,
updates: CommitmentUpdate, corrupt_forward: bool, limit_events: ProcessMessages,
- nodes: &[HarnessNode<'_>; 3], out: &Out,
+ nodes: &[HarnessNode<'_>; 3], _payments: &mut PaymentTracker, out: &Out,
) -> Option<MessageSendEvent> {
let dest_idx = find_destination_node(nodes, &node_id);
let dest = &nodes[dest_idx];
@@ -3127,7 +3183,7 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
fn process_msg_event<Out: Output + MaybeSend + MaybeSync>(
node_idx: usize, source_node_id: PublicKey, event: MessageSendEvent,
corrupt_forward: bool, limit_events: ProcessMessages, nodes: &[HarnessNode<'_>; 3],
- close_tracker: &ChannelCloseTracker, out: &Out,
+ payments: &mut PaymentTracker, close_tracker: &ChannelCloseTracker, out: &Out,
) -> Option<MessageSendEvent> {
// Always deliver message events, even when the harness knows they are stale,
// so message handlers exercise their normal error paths.
@@ -3142,6 +3198,7 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
corrupt_forward,
limit_events,
nodes,
+ payments,
out,
)
},
@@ -3270,6 +3327,7 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
}
let nodes = &self.nodes;
+ let payments = &mut self.payments;
let close_tracker = &self.close_tracker;
let out = &self.out;
let queues = &mut self.queues;
@@ -3291,6 +3349,7 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
corrupt_forward,
limit_events,
nodes,
+ payments,
close_tracker,
out,
);
@@ -3341,8 +3400,10 @@ impl<'a, Out: Output + MaybeSend + MaybeSync> Harness<'a, Out> {
events::Event::ProbeSuccessful { payment_id, .. } => {
payments.nodes[node_idx].mark_successful_probe(payment_id);
},
- events::Event::PaymentFailed { payment_id, .. }
- | events::Event::ProbeFailed { payment_id, .. } => {
+ events::Event::PaymentFailed { payment_id, .. } => {
+ payments.nodes[node_idx].mark_resolved_without_hash(payment_id);
+ },
+ events::Event::ProbeFailed { payment_id, .. } => {
payments.nodes[node_idx].mark_resolved_without_hash(payment_id);
},
events::Event::PaymentClaimed { .. } => {},
Risk score
Our methodology →Why this scored 13/100
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