ChannelKeys - separate commitment revocation from getting the per-commitment point

[rust-lightning] / lightning / src / ln / chan_utils.rs

diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs
index 53a6e25f764cfd6fe75c0aa99abf08d08ea34246..ba175733abeb632065d0cf16fe44ca13b6560b66 100644 (file)
--- a/lightning/src/ln/chan_utils.rs
+++ b/lightning/src/ln/chan_utils.rs
@@ -5,7 +5,8 @@
 use bitcoin::blockdata::script::{Script,Builder};
 use bitcoin::blockdata::opcodes;
 use bitcoin::blockdata::transaction::{TxIn,TxOut,OutPoint,Transaction, SigHashType};
-use bitcoin::consensus::encode::{self, Decodable, Encodable};
+use bitcoin::consensus::encode::{Decodable, Encodable};
+use bitcoin::consensus::encode;
 use bitcoin::util::bip143;
 
 use bitcoin::hashes::{Hash, HashEngine};
@@ -51,7 +52,8 @@ impl HTLCType {
 // Various functions for key derivation and transaction creation for use within channels. Primarily
 // used in Channel and ChannelMonitor.
 
-pub(super) fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
+/// Build the commitment secret from the seed and the commitment number
+pub fn build_commitment_secret(commitment_seed: &[u8; 32], idx: u64) -> [u8; 32] {
        let mut res: [u8; 32] = commitment_seed.clone();
        for i in 0..48 {
                let bitpos = 47 - i;
@@ -461,7 +463,7 @@ pub fn make_funding_redeemscript(a: &PublicKey, b: &PublicKey) -> Script {
 }
 
 /// panics if htlc.transaction_output_index.is_none()!
-pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u64, to_self_delay: u16, htlc: &HTLCOutputInCommitment, a_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
+pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u32, to_self_delay: u16, htlc: &HTLCOutputInCommitment, a_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
        let mut txins: Vec<TxIn> = Vec::new();
        txins.push(TxIn {
                previous_output: OutPoint {
@@ -474,9 +476,9 @@ pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u64, to_self_del
        });
 
        let total_fee = if htlc.offered {
-                       feerate_per_kw * HTLC_TIMEOUT_TX_WEIGHT / 1000
+                       feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000
                } else {
-                       feerate_per_kw * HTLC_SUCCESS_TX_WEIGHT / 1000
+                       feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000
                };
 
        let mut txouts: Vec<TxOut> = Vec::new();
@@ -495,8 +497,8 @@ pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u64, to_self_del
 
 #[derive(Clone)]
 /// We use this to track local commitment transactions and put off signing them until we are ready
-/// to broadcast. Eventually this will require a signer which is possibly external, but for now we
-/// just pass in the SecretKeys required.
+/// to broadcast. This class can be used inside a signer implementation to generate a signature
+/// given the relevant secret key.
 pub struct LocalCommitmentTransaction {
        // TODO: We should migrate away from providing the transaction, instead providing enough to
        // allow the ChannelKeys to construct it from scratch. Luckily we already have HTLC data here,
@@ -512,7 +514,7 @@ pub struct LocalCommitmentTransaction {
        pub local_keys: TxCreationKeys,
        /// The feerate paid per 1000-weight-unit in this commitment transaction. This value is
        /// controlled by the channel initiator.
-       pub feerate_per_kw: u64,
+       pub feerate_per_kw: u32,
        /// The HTLCs and remote htlc signatures which were included in this commitment transaction.
        ///
        /// Note that this includes all HTLCs, including ones which were considered dust and not
@@ -560,7 +562,7 @@ impl LocalCommitmentTransaction {
 
        /// Generate a new LocalCommitmentTransaction based on a raw commitment transaction,
        /// remote signature and both parties keys
-       pub(crate) fn new_missing_local_sig(unsigned_tx: Transaction, their_sig: Signature, our_funding_key: &PublicKey, their_funding_key: &PublicKey, local_keys: TxCreationKeys, feerate_per_kw: u64, htlc_data: Vec<(HTLCOutputInCommitment, Option<Signature>)>) -> LocalCommitmentTransaction {
+       pub(crate) fn new_missing_local_sig(unsigned_tx: Transaction, their_sig: Signature, our_funding_key: &PublicKey, their_funding_key: &PublicKey, local_keys: TxCreationKeys, feerate_per_kw: u32, htlc_data: Vec<(HTLCOutputInCommitment, Option<Signature>)>) -> LocalCommitmentTransaction {
                if unsigned_tx.input.len() != 1 { panic!("Tried to store a commitment transaction that had input count != 1!"); }
                if unsigned_tx.input[0].witness.len() != 0 { panic!("Tried to store a signed commitment transaction?"); }