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Include 0FC channels in `chan_utils::test_anchors`
Public commit record
50/100 · Thin
What the developer wrote
Authored by Leo Nash
Include 0FC channels in `chan_utils::test_anchors`
✓ Specific, descriptive subject✓ Names a concrete action or component! No meaningful explanatory body
What changed, and why it matters
This commit only adds and updates unit tests for channel anchor output handling in the Lightning Dev Kit library. It does not change any production code, so it cannot introduce a runtime security vulnerability. The change expands test coverage to include a newer channel type known as 'zero-fee commitment' (0FC) channels, ensuring the existing code correctly builds transactions with shared anchors.
Recommended action
No security action required. Treat as a normal test-coverage improvement.
Security signals we found
No strong security signals were identified.
Evidence from the diff
The diff modifies lightning/src/ln/chan_utils.rs, specifically the test_anchors unit test. It increases the test channel value from 3000 to 4000 satoshis, adds assertions for existing keyed anchor outputs, and adds new test cases for ChannelTypeFeatures::anchors_zero_fee_commitments() (0FC) channels using shared_anchor_script_pubkey(). It also updates comments and renames one test section from ‘with anchors’ to ‘with keyed anchors’. No production logic is altered.
Changed components
lightning/src/ln/chan_utils.rs (unit tests only)Inspect captured patch +50 / −4
diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 7c02078..9063b29 100644
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -2206,7 +2206,8 @@ mod tests {
use super::{ChannelPublicKeys, CounterpartyCommitmentSecrets};
use crate::chain;
use crate::ln::chan_utils::{
- get_htlc_redeemscript, get_to_countersigner_keyed_anchor_redeemscript,
+ get_htlc_redeemscript, get_keyed_anchor_redeemscript,
+ get_to_countersigner_keyed_anchor_redeemscript, shared_anchor_script_pubkey,
BuiltCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction,
CounterpartyChannelTransactionParameters, HTLCOutputInCommitment,
TrustedCommitmentTransaction,
@@ -2254,7 +2255,7 @@ mod tests {
funding_outpoint: Some(chain::transaction::OutPoint { txid: Txid::all_zeros(), index: 0 }),
splice_parent_funding_txid: None,
channel_type_features: ChannelTypeFeatures::only_static_remote_key(),
- channel_value_satoshis: 3000,
+ channel_value_satoshis: 4000,
};
Self {
@@ -2297,14 +2298,42 @@ mod tests {
let tx = builder.build(1000, 2000, Vec::new());
assert_eq!(tx.built.transaction.output.len(), 4);
assert_eq!(tx.built.transaction.output[3].script_pubkey, get_to_countersigner_keyed_anchor_redeemscript(&builder.counterparty_pubkeys.payment_point).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, get_keyed_anchor_redeemscript(&builder.channel_parameters.holder_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 330);
+ assert_eq!(tx.built.transaction.output[1].script_pubkey, get_keyed_anchor_redeemscript(&builder.counterparty_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[1].value.to_sat(), 330);
// Generate broadcaster output and anchor
let tx = builder.build(3000, 0, Vec::new());
assert_eq!(tx.built.transaction.output.len(), 2);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, get_keyed_anchor_redeemscript(&builder.channel_parameters.holder_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 330);
// Generate counterparty output and anchor
let tx = builder.build(0, 3000, Vec::new());
assert_eq!(tx.built.transaction.output.len(), 2);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, get_keyed_anchor_redeemscript(&builder.counterparty_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 330);
+
+ // Generate broadcaster and counterparty outputs as well as a single anchor
+ builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_fee_commitments();
+ let tx = builder.build(1000, 2000, Vec::new());
+ assert_eq!(tx.built.transaction.output.len(), 3);
+ assert_eq!(tx.built.transaction.output[2].script_pubkey, bitcoin::address::Address::p2wpkh(&CompressedPublicKey(builder.counterparty_pubkeys.payment_point), Network::Testnet).script_pubkey());
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, shared_anchor_script_pubkey());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 240); // remember total channel value is 4000sat
+
+ // Generate broadcaster output and anchor
+ let tx = builder.build(3000, 0, Vec::new());
+ assert_eq!(tx.built.transaction.output.len(), 2);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, shared_anchor_script_pubkey());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 240); // remember total channel value is 4000sat
+
+ // Generate counterparty output and anchor
+ let tx = builder.build(0, 3000, Vec::new());
+ assert_eq!(tx.built.transaction.output.len(), 2);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, shared_anchor_script_pubkey());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 240); // remember total channel value is 4000sat
let received_htlc = HTLCOutputInCommitment {
offered: false,
@@ -2322,7 +2351,7 @@ mod tests {
transaction_output_index: None,
};
- // Generate broadcaster output and received and offered HTLC outputs, w/o anchors
+ // Generate broadcaster output and received and offered HTLC outputs, w/o anchors
builder.channel_parameters.channel_type_features = ChannelTypeFeatures::only_static_remote_key();
let tx = builder.build(3000, 0, vec![received_htlc.clone(), offered_htlc.clone()]);
let keys = tx.trust().keys();
@@ -2334,16 +2363,33 @@ mod tests {
assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::only_static_remote_key(), &keys).to_p2wsh().to_hex_string(),
"0020215d61bba56b19e9eadb6107f5a85d7f99c40f65992443f69229c290165bc00d");
- // Generate broadcaster output and received and offered HTLC outputs, with anchors
+ // Generate broadcaster output and received and offered HTLC outputs, with keyed anchors
builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies();
let tx = builder.build(3000, 0, vec![received_htlc.clone(), offered_htlc.clone()]);
assert_eq!(tx.built.transaction.output.len(), 5);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, get_keyed_anchor_redeemscript(&builder.channel_parameters.holder_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 330);
+ assert_eq!(tx.built.transaction.output[1].script_pubkey, get_keyed_anchor_redeemscript(&builder.counterparty_pubkeys.funding_pubkey).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[1].value.to_sat(), 330);
assert_eq!(tx.built.transaction.output[2].script_pubkey, get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_p2wsh());
assert_eq!(tx.built.transaction.output[3].script_pubkey, get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_p2wsh());
assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_p2wsh().to_hex_string(),
"0020b70d0649c72b38756885c7a30908d912a7898dd5d79457a7280b8e9a20f3f2bc");
assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies(), &keys).to_p2wsh().to_hex_string(),
"002087a3faeb1950a469c0e2db4a79b093a41b9526e5a6fc6ef5cb949bde3be379c7");
+
+ // Generate broadcaster output and received and offered HTLC outputs, with P2A anchors
+ builder.channel_parameters.channel_type_features = ChannelTypeFeatures::anchors_zero_fee_commitments();
+ let tx = builder.build(3000, 0, vec![received_htlc.clone(), offered_htlc.clone()]);
+ assert_eq!(tx.built.transaction.output.len(), 4);
+ assert_eq!(tx.built.transaction.output[0].script_pubkey, shared_anchor_script_pubkey());
+ assert_eq!(tx.built.transaction.output[0].value.to_sat(), 0);
+ assert_eq!(tx.built.transaction.output[1].script_pubkey, get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_fee_commitments(), &keys).to_p2wsh());
+ assert_eq!(tx.built.transaction.output[2].script_pubkey, get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_fee_commitments(), &keys).to_p2wsh());
+ assert_eq!(get_htlc_redeemscript(&received_htlc, &ChannelTypeFeatures::anchors_zero_fee_commitments(), &keys).to_p2wsh().to_hex_string(),
+ "0020e43a7c068553003fe68fcae424fb7b28ec5ce48cd8b6744b3945631389bad2fb");
+ assert_eq!(get_htlc_redeemscript(&offered_htlc, &ChannelTypeFeatures::anchors_zero_fee_commitments(), &keys).to_p2wsh().to_hex_string(),
+ "0020215d61bba56b19e9eadb6107f5a85d7f99c40f65992443f69229c290165bc00d");
}
#[test]
Risk score
Our methodology →Why this scored 15/100
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