Use new get_commitment_transaction_number_obscure_factor utility function

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index 32ca3d30b91fd1cd076a7169bab9b0062e9fc3c3..c319c5524cef4768239eebcd05b510b492a8e57f 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -14,7 +14,7 @@ use bitcoin::blockdata::opcodes;
 use bitcoin::util::bip143;
 use bitcoin::consensus::encode;
 
-use bitcoin::hashes::{Hash, HashEngine};
+use bitcoin::hashes::Hash;
 use bitcoin::hashes::sha256::Hash as Sha256;
 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
 
@@ -26,7 +26,7 @@ use ln::features::{ChannelFeatures, InitFeatures};
 use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
-use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS};
+use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor};
 use ln::chan_utils;
 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
 use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};
@@ -795,29 +795,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                Ok(chan)
        }
 
-       // Utilities to build transactions:
-
-       fn get_commitment_transaction_number_obscure_factor(&self) -> u64 {
-               let mut sha = Sha256::engine();
-
-               let counterparty_payment_point = &self.get_counterparty_pubkeys().payment_point.serialize();
-               if self.is_outbound() {
-                       sha.input(&self.get_holder_pubkeys().payment_point.serialize());
-                       sha.input(counterparty_payment_point);
-               } else {
-                       sha.input(counterparty_payment_point);
-                       sha.input(&self.get_holder_pubkeys().payment_point.serialize());
-               }
-               let res = Sha256::from_engine(sha).into_inner();
-
-               ((res[26] as u64) << 5*8) |
-               ((res[27] as u64) << 4*8) |
-               ((res[28] as u64) << 3*8) |
-               ((res[29] as u64) << 2*8) |
-               ((res[30] as u64) << 1*8) |
-               ((res[31] as u64) << 0*8)
-       }
-
        /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
        /// transaction is referred to as "a's transaction" implying that a will be able to broadcast
        /// the transaction. Thus, b will generally be sending a signature over such a transaction to
@@ -846,7 +823,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let mut local_htlc_total_msat = 0;
                let mut value_to_self_msat_offset = 0;
 
-               log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for {}, generated by {} with fee {}...", commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number), self.get_commitment_transaction_number_obscure_factor(), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
+               log_trace!(logger, "Building commitment transaction number {} (really {} xor {}) for {}, generated by {} with fee {}...", commitment_number, (INITIAL_COMMITMENT_NUMBER - commitment_number), get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound()), if local { "us" } else { "remote" }, if generated_by_local { "us" } else { "remote" }, feerate_per_kw);
 
                macro_rules! get_htlc_in_commitment {
                        ($htlc: expr, $offered: expr) => {
@@ -1539,12 +1516,13 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
                let funding_redeemscript = self.get_funding_redeemscript();
                let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
                let mut channel_monitor = ChannelMonitor::new(self.holder_keys.clone(),
                                                              &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
                                                              &self.destination_script, (funding_txo, funding_txo_script.clone()),
                                                              &self.channel_transaction_parameters,
                                                              funding_redeemscript.clone(), self.channel_value_satoshis,
-                                                             self.get_commitment_transaction_number_obscure_factor(),
+                                                             obscure_factor,
                                                              holder_commitment_tx);
 
                channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);
@@ -1608,12 +1586,13 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                let funding_redeemscript = self.get_funding_redeemscript();
                let funding_txo = self.get_funding_txo().unwrap();
                let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.get_holder_pubkeys().payment_point, &self.get_counterparty_pubkeys().payment_point, self.is_outbound());
                let mut channel_monitor = ChannelMonitor::new(self.holder_keys.clone(),
                                                              &self.shutdown_pubkey, self.get_holder_selected_contest_delay(),
                                                              &self.destination_script, (funding_txo, funding_txo_script),
                                                              &self.channel_transaction_parameters,
                                                              funding_redeemscript.clone(), self.channel_value_satoshis,
-                                                             self.get_commitment_transaction_number_obscure_factor(),
+                                                             obscure_factor,
                                                              holder_commitment_tx);
 
                channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.cur_counterparty_commitment_transaction_number, self.counterparty_cur_commitment_point.unwrap(), logger);