aljaz/lightning
1
0
Fork 0
mirror of https://github.com/aljazceru/lightning.git synced 2026-01-10 01:24:30 +01:00
Code Issues Packages Projects Releases Wiki Activity

closingd, lightningd: use bitcoin_tx_2of2_input_witness_weight

Browse Source 
This fixes lightningd's chronic weight underestimate.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Fixed: closingd: more accurate weight estimation helps mutual closing near min/max feerates.
This commit is contained in:
Rusty Russell
2022-01-26 12:42:34 +10:30
committed by Christian Decker
parent 8a8d7c4243
commit de28bbd792
3 changed files with 5 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

17
closingd/closingd.c
View File

@@ -579,10 +579,6 @@ static size_t closing_tx_weight_estimate(u8 *scriptpubkey[NUM_SIDES],
/* We create a dummy close */
struct bitcoin_tx *tx;
struct bitcoin_outpoint dummy_funding;
struct bitcoin_signature dummy_sig;
struct privkey dummy_privkey;
struct pubkey dummy_pubkey;
u8 **witness;
memset(&dummy_funding, 0, sizeof(dummy_funding));
tx = create_close_tx(tmpctx, chainparams,
@@ -594,17 +590,8 @@ static size_t closing_tx_weight_estimate(u8 *scriptpubkey[NUM_SIDES],
out[REMOTE],
dust_limit);
/* Create a signature, any signature, so we can weigh fully "signed"
* tx. */
dummy_sig.sighash_type = SIGHASH_ALL;
memset(&dummy_privkey, 1, sizeof(dummy_privkey));
sign_hash(&dummy_privkey, &dummy_funding.txid.shad, &dummy_sig.s);
pubkey_from_privkey(&dummy_privkey, &dummy_pubkey);
witness = bitcoin_witness_2of2(NULL, &dummy_sig, &dummy_sig,
&dummy_pubkey, &dummy_pubkey);
bitcoin_tx_input_set_witness(tx, 0, take(witness));
return bitcoin_tx_weight(tx);
/* We will have to append the witness */
return bitcoin_tx_weight(tx) + bitcoin_tx_2of2_input_witness_weight();
}
/* Get the minimum and desired fees */

4
lightningd/closing_control.c
View File

@@ -202,7 +202,9 @@ static bool closing_fee_is_acceptable(struct lightningd *ld,
last_fee = calc_tx_fee(channel->funding_sats, channel->last_tx);
/* Weight once we add in sigs. */
weight = bitcoin_tx_weight(tx) + bitcoin_tx_input_sig_weight() * 2;
assert(!tx->wtx->inputs[0].witness
|| tx->wtx->inputs[0].witness->num_items == 0);
weight = bitcoin_tx_weight(tx) + bitcoin_tx_2of2_input_witness_weight();
log_debug(channel->log, "Their actual closing tx fee is %s"
" vs previous %s: weight is %"PRIu64,

1
tests/test_closing.py
View File

@@ -3655,7 +3655,6 @@ def test_close_twice(node_factory, executor):
assert fut2.result(TIMEOUT)['type'] == 'mutual'
@pytest.mark.xfail(strict=True)
def test_close_weight_estimate(node_factory, bitcoind):
"""closingd uses the expected closing tx weight to constrain fees; make sure that lightningd agrees
once it has the actual agreed tx"""