Simplify handling of OnChainTx.holder_commitment

It is no longer optional since it is available at construction time.
This commit is contained in:
Devrandom 2021-01-14 13:45:31 -08:00
parent 63c56a4a86
commit 0b20cf62e7
2 changed files with 69 additions and 84 deletions

View file

@ -969,7 +969,6 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
let key_derivation_params = keys.key_derivation_params();
let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
let mut onchain_tx_handler = OnchainTxHandler::new(destination_script.clone(), keys, channel_parameters.clone());
let secp_ctx = Secp256k1::new();
@ -991,7 +990,9 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
};
(holder_commitment_tx, trusted_tx.commitment_number())
};
onchain_tx_handler.provide_latest_holder_tx(initial_holder_commitment_tx);
let onchain_tx_handler =
OnchainTxHandler::new(destination_script.clone(), keys, channel_parameters.clone(), initial_holder_commitment_tx);
let mut outputs_to_watch = HashMap::new();
outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
@ -1725,28 +1726,26 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
log_trace!(logger, "Getting signed latest holder commitment transaction!");
self.holder_tx_signed = true;
if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
let txid = commitment_tx.txid();
let mut res = vec![commitment_tx];
for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
if let Some(vout) = htlc.0.transaction_output_index {
let preimage = if !htlc.0.offered {
if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
// We can't build an HTLC-Success transaction without the preimage
continue;
}
} else { None };
if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
&::bitcoin::OutPoint { txid, vout }, &preimage) {
res.push(htlc_tx);
let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
let txid = commitment_tx.txid();
let mut res = vec![commitment_tx];
for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
if let Some(vout) = htlc.0.transaction_output_index {
let preimage = if !htlc.0.offered {
if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
// We can't build an HTLC-Success transaction without the preimage
continue;
}
} else { None };
if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
&::bitcoin::OutPoint { txid, vout }, &preimage) {
res.push(htlc_tx);
}
}
// We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
// The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
return res
}
Vec::new()
// We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
// The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
return res;
}
/// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
@ -1755,26 +1754,24 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
#[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
log_trace!(logger, "Getting signed copy of latest holder commitment transaction!");
if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript) {
let txid = commitment_tx.txid();
let mut res = vec![commitment_tx];
for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
if let Some(vout) = htlc.0.transaction_output_index {
let preimage = if !htlc.0.offered {
if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
// We can't build an HTLC-Success transaction without the preimage
continue;
}
} else { None };
if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
&::bitcoin::OutPoint { txid, vout }, &preimage) {
res.push(htlc_tx);
let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
let txid = commitment_tx.txid();
let mut res = vec![commitment_tx];
for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
if let Some(vout) = htlc.0.transaction_output_index {
let preimage = if !htlc.0.offered {
if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
// We can't build an HTLC-Success transaction without the preimage
continue;
}
} else { None };
if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
&::bitcoin::OutPoint { txid, vout }, &preimage) {
res.push(htlc_tx);
}
}
return res
}
Vec::new()
return res
}
/// Processes transactions in a newly connected block, which may result in any of the following:
@ -1853,15 +1850,14 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
}
if should_broadcast {
self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript) {
self.holder_tx_signed = true;
let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx);
let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
if !new_outputs.is_empty() {
watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
}
claimable_outpoints.append(&mut new_outpoints);
let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
self.holder_tx_signed = true;
let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx);
let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
if !new_outputs.is_empty() {
watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
}
claimable_outpoints.append(&mut new_outpoints);
}
if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&height) {
for ev in events {

View file

@ -35,6 +35,7 @@ use util::byte_utils;
use std::collections::{HashMap, hash_map};
use std::cmp;
use std::ops::Deref;
use std::mem::replace;
const MAX_ALLOC_SIZE: usize = 64*1024;
@ -241,7 +242,7 @@ impl Writeable for Option<Vec<Option<(usize, Signature)>>> {
/// do RBF bumping if possible.
pub struct OnchainTxHandler<ChanSigner: ChannelKeys> {
destination_script: Script,
holder_commitment: Option<HolderCommitmentTransaction>,
holder_commitment: HolderCommitmentTransaction,
// holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
// transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
// the set of HTLCs in the HolderCommitmentTransaction.
@ -423,13 +424,13 @@ impl<'a, K: KeysInterface> ReadableArgs<&'a K> for OnchainTxHandler<K::ChanKeySi
}
impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
pub(crate) fn new(destination_script: Script, keys: ChanSigner, channel_parameters: ChannelTransactionParameters) -> Self {
pub(crate) fn new(destination_script: Script, keys: ChanSigner, channel_parameters: ChannelTransactionParameters, holder_commitment: HolderCommitmentTransaction) -> Self {
let key_storage = keys;
OnchainTxHandler {
destination_script,
holder_commitment: None,
holder_commitment,
holder_htlc_sigs: None,
prev_holder_commitment: None,
prev_holder_htlc_sigs: None,
@ -663,10 +664,10 @@ impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
return None;
},
&InputMaterial::Funding { ref funding_redeemscript } => {
let signed_tx = self.get_fully_signed_holder_tx(funding_redeemscript).unwrap();
let signed_tx = self.get_fully_signed_holder_tx(funding_redeemscript);
// Timer set to $NEVER given we can't bump tx without anchor outputs
log_trace!(logger, "Going to broadcast Holder Transaction {} claiming funding output {} from {}...", signed_tx.txid(), outp.vout, outp.txid);
return Some((None, self.holder_commitment.as_ref().unwrap().feerate_per_kw(), signed_tx));
return Some((None, self.holder_commitment.feerate_per_kw(), signed_tx));
}
_ => unreachable!()
}
@ -904,9 +905,8 @@ impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
}
pub(crate) fn provide_latest_holder_tx(&mut self, tx: HolderCommitmentTransaction) {
self.prev_holder_commitment = self.holder_commitment.take();
self.prev_holder_commitment = Some(replace(&mut self.holder_commitment, tx));
self.holder_htlc_sigs = None;
self.holder_commitment = Some(tx);
}
// Normally holder HTLCs are signed at the same time as the holder commitment tx. However,
@ -914,15 +914,13 @@ impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
// ChannelMonitor replica, so we handle that case here.
fn sign_latest_holder_htlcs(&mut self) {
if self.holder_htlc_sigs.is_none() {
if let Some(ref holder_commitment) = self.holder_commitment {
let (_sig, sigs) = self.key_storage.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, sigs));
}
let (_sig, sigs) = self.key_storage.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, sigs));
}
}
// Normally only the latest commitment tx and HTLCs need to be signed. However, in some
// configurations we may have updated our holder commtiment but a replica of the ChannelMonitor
// configurations we may have updated our holder commitment but a replica of the ChannelMonitor
// broadcast the previous one before we sync with it. We handle that case here.
fn sign_prev_holder_htlcs(&mut self) {
if self.prev_holder_htlc_sigs.is_none() {
@ -947,43 +945,34 @@ impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
// have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after Channel::get_outbound_funding_created,
// before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
// to monitor before.
pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Option<Transaction> {
if let Some(ref mut holder_commitment) = self.holder_commitment {
let (sig, htlc_sigs) = self.key_storage.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("signing holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, htlc_sigs));
Some(holder_commitment.add_holder_sig(funding_redeemscript, sig))
} else {
None
}
pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
let (sig, htlc_sigs) = self.key_storage.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
}
#[cfg(any(test, feature="unsafe_revoked_tx_signing"))]
pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Option<Transaction> {
if let Some(ref mut holder_commitment) = self.holder_commitment {
let (sig, htlc_sigs) = self.key_storage.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, htlc_sigs));
Some(holder_commitment.add_holder_sig(funding_redeemscript, sig))
} else {
None
}
pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
let (sig, htlc_sigs) = self.key_storage.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
}
pub(crate) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
let mut htlc_tx = None;
if self.holder_commitment.is_some() {
let commitment_txid = self.holder_commitment.as_ref().unwrap().trust().txid();
if commitment_txid == outp.txid {
self.sign_latest_holder_htlcs();
if let &Some(ref htlc_sigs) = &self.holder_htlc_sigs {
let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
let holder_commitment = self.holder_commitment.as_ref().unwrap();
let trusted_tx = holder_commitment.trust();
let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[*htlc_idx];
htlc_tx = Some(trusted_tx
.get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
}
let commitment_txid = self.holder_commitment.trust().txid();
// Check if the HTLC spends from the current holder commitment
if commitment_txid == outp.txid {
self.sign_latest_holder_htlcs();
if let &Some(ref htlc_sigs) = &self.holder_htlc_sigs {
let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
let trusted_tx = self.holder_commitment.trust();
let counterparty_htlc_sig = self.holder_commitment.counterparty_htlc_sigs[*htlc_idx];
htlc_tx = Some(trusted_tx
.get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
}
}
// If the HTLC doesn't spend the current holder commitment, check if it spends the previous one
if htlc_tx.is_none() && self.prev_holder_commitment.is_some() {
let commitment_txid = self.prev_holder_commitment.as_ref().unwrap().trust().txid();
if commitment_txid == outp.txid {