X-Git-Url: http://git.bitcoin.ninja/index.cgi?p=rust-lightning;a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fonchaintx.rs;h=186793581cea9cd05f9d281b77074508c72ba8c7;hp=40d9f18abb71efc445acb26218a6c4e89a3cc99b;hb=359b3d5702b585a67e4e6d4044c35caf86bd787d;hpb=0bc82ee1bc357137f59d45abaff60f63032cf4c9 diff --git a/lightning/src/ln/onchaintx.rs b/lightning/src/ln/onchaintx.rs index 40d9f18a..18679358 100644 --- a/lightning/src/ln/onchaintx.rs +++ b/lightning/src/ln/onchaintx.rs @@ -15,14 +15,15 @@ use secp256k1; use ln::msgs::DecodeError; use ln::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER, InputMaterial, ClaimRequest}; -use ln::chan_utils::HTLCType; +use ln::channelmanager::PaymentPreimage; +use ln::chan_utils::{HTLCType, LocalCommitmentTransaction}; use chain::chaininterface::{FeeEstimator, BroadcasterInterface, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT}; use chain::keysinterface::ChannelKeys; use util::logger::Logger; use util::ser::{ReadableArgs, Readable, Writer, Writeable}; use util::byte_utils; -use std::collections::{HashMap, hash_map, HashSet}; +use std::collections::{HashMap, hash_map}; use std::sync::Arc; use std::cmp; use std::ops::Deref; @@ -52,7 +53,7 @@ enum OnchainEvent { pub struct ClaimTxBumpMaterial { // At every block tick, used to check if pending claiming tx is taking too // much time for confirmation and we need to bump it. - height_timer: u32, + height_timer: Option, // Tracked in case of reorg to wipe out now-superflous bump material feerate_previous: u64, // Soonest timelocks among set of outpoints claimed, used to compute @@ -64,7 +65,7 @@ pub struct ClaimTxBumpMaterial { impl Writeable for ClaimTxBumpMaterial { fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { - writer.write_all(&byte_utils::be32_to_array(self.height_timer))?; + self.height_timer.write(writer)?; writer.write_all(&byte_utils::be64_to_array(self.feerate_previous))?; writer.write_all(&byte_utils::be32_to_array(self.soonest_timelock))?; writer.write_all(&byte_utils::be64_to_array(self.per_input_material.len() as u64))?; @@ -141,6 +142,9 @@ macro_rules! subtract_high_prio_fee { /// do RBF bumping if possible. pub struct OnchainTxHandler { destination_script: Script, + local_commitment: Option, + prev_local_commitment: Option, + local_csv: u16, key_storage: ChanSigner, @@ -180,6 +184,10 @@ pub struct OnchainTxHandler { impl OnchainTxHandler { pub(crate) fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { self.destination_script.write(writer)?; + self.local_commitment.write(writer)?; + self.prev_local_commitment.write(writer)?; + + self.local_csv.write(writer)?; self.key_storage.write(writer)?; @@ -222,6 +230,11 @@ impl ReadableArgs> for OnchainTx fn read(reader: &mut R, logger: Arc) -> Result { let destination_script = Readable::read(reader)?; + let local_commitment = Readable::read(reader)?; + let prev_local_commitment = Readable::read(reader)?; + + let local_csv = Readable::read(reader)?; + let key_storage = Readable::read(reader)?; let pending_claim_requests_len: u64 = Readable::read(reader)?; @@ -269,6 +282,9 @@ impl ReadableArgs> for OnchainTx Ok(OnchainTxHandler { destination_script, + local_commitment, + prev_local_commitment, + local_csv, key_storage, claimable_outpoints, pending_claim_requests, @@ -280,12 +296,15 @@ impl ReadableArgs> for OnchainTx } impl OnchainTxHandler { - pub(super) fn new(destination_script: Script, keys: ChanSigner, logger: Arc) -> Self { + pub(super) fn new(destination_script: Script, keys: ChanSigner, local_csv: u16, logger: Arc) -> Self { let key_storage = keys; OnchainTxHandler { destination_script, + local_commitment: None, + prev_local_commitment: None, + local_csv, key_storage, pending_claim_requests: HashMap::new(), claimable_outpoints: HashMap::new(), @@ -342,7 +361,7 @@ impl OnchainTxHandler { /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize coutnerparty onchain) lays on the assumption of claim transactions getting confirmed before timelock expiration /// (CSV or CLTV following cases). In case of high-fee spikes, claim tx may stuck in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or Child-Pay-For-Parent. - fn generate_claim_tx(&self, height: u32, cached_claim_datas: &ClaimTxBumpMaterial, fee_estimator: F) -> Option<(u32, u64, Transaction)> + fn generate_claim_tx(&mut self, height: u32, cached_claim_datas: &ClaimTxBumpMaterial, fee_estimator: F) -> Option<(Option, u64, Transaction)> where F::Target: FeeEstimator { if cached_claim_datas.per_input_material.len() == 0 { return None } // But don't prune pending claiming request yet, we may have to resurrect HTLCs @@ -407,9 +426,10 @@ impl OnchainTxHandler { // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it). - let new_timer = Self::get_height_timer(height, cached_claim_datas.soonest_timelock); + let new_timer = Some(Self::get_height_timer(height, cached_claim_datas.soonest_timelock)); let mut inputs_witnesses_weight = 0; let mut amt = 0; + let mut dynamic_fee = true; for per_outp_material in cached_claim_datas.per_input_material.values() { match per_outp_material { &InputMaterial::Revoked { ref witness_script, ref is_htlc, ref amount, .. } => { @@ -420,72 +440,108 @@ impl OnchainTxHandler { inputs_witnesses_weight += Self::get_witnesses_weight(if preimage.is_some() { &[InputDescriptors::OfferedHTLC] } else { &[InputDescriptors::ReceivedHTLC] }); amt += *amount; }, - &InputMaterial::LocalHTLC { .. } => { return None; } - } - } - - let predicted_weight = bumped_tx.get_weight() + inputs_witnesses_weight; - let mut new_feerate; - // If old feerate is 0, first iteration of this claim, use normal fee calculation - if cached_claim_datas.feerate_previous != 0 { - if let Some((new_fee, feerate)) = RBF_bump!(amt, cached_claim_datas.feerate_previous, fee_estimator, predicted_weight as u64) { - // If new computed fee is superior at the whole claimable amount burn all in fees - if new_fee > amt { - bumped_tx.output[0].value = 0; - } else { - bumped_tx.output[0].value = amt - new_fee; + &InputMaterial::LocalHTLC { .. } => { + dynamic_fee = false; + }, + &InputMaterial::Funding { .. } => { + dynamic_fee = false; } - new_feerate = feerate; - } else { return None; } - } else { - if subtract_high_prio_fee!(self, fee_estimator, amt, predicted_weight, new_feerate) { - bumped_tx.output[0].value = amt; - } else { return None; } + } } - assert!(new_feerate != 0); - - for (i, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() { - match per_outp_material { - &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount } => { - let sighash_parts = bip143::SighashComponents::new(&bumped_tx); - let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]); - let sig = self.secp_ctx.sign(&sighash, &key); - bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); - bumped_tx.input[i].witness[0].push(SigHashType::All as u8); - if *is_htlc { - bumped_tx.input[i].witness.push(pubkey.unwrap().clone().serialize().to_vec()); + if dynamic_fee { + let predicted_weight = bumped_tx.get_weight() + inputs_witnesses_weight; + let mut new_feerate; + // If old feerate is 0, first iteration of this claim, use normal fee calculation + if cached_claim_datas.feerate_previous != 0 { + if let Some((new_fee, feerate)) = RBF_bump!(amt, cached_claim_datas.feerate_previous, fee_estimator, predicted_weight as u64) { + // If new computed fee is superior at the whole claimable amount burn all in fees + if new_fee > amt { + bumped_tx.output[0].value = 0; } else { - bumped_tx.input[i].witness.push(vec!(1)); + bumped_tx.output[0].value = amt - new_fee; } - bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); - log_trace!(self, "Going to broadcast Penalty Transaction {} claiming revoked {} output {} from {} with new feerate {}...", bumped_tx.txid(), if !is_htlc { "to_local" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { "offered" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { "received" } else { "" }, outp.vout, outp.txid, new_feerate); - }, - &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => { - if !preimage.is_some() { bumped_tx.lock_time = *locktime }; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation - let sighash_parts = bip143::SighashComponents::new(&bumped_tx); - let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]); - let sig = self.secp_ctx.sign(&sighash, &key); - bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); - bumped_tx.input[i].witness[0].push(SigHashType::All as u8); - if let &Some(preimage) = preimage { - bumped_tx.input[i].witness.push(preimage.clone().0.to_vec()); - } else { - bumped_tx.input[i].witness.push(vec![]); + new_feerate = feerate; + } else { return None; } + } else { + if subtract_high_prio_fee!(self, fee_estimator, amt, predicted_weight, new_feerate) { + bumped_tx.output[0].value = amt; + } else { return None; } + } + assert!(new_feerate != 0); + + for (i, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() { + match per_outp_material { + &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount } => { + let sighash_parts = bip143::SighashComponents::new(&bumped_tx); + let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]); + let sig = self.secp_ctx.sign(&sighash, &key); + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + if *is_htlc { + bumped_tx.input[i].witness.push(pubkey.unwrap().clone().serialize().to_vec()); + } else { + bumped_tx.input[i].witness.push(vec!(1)); + } + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + log_trace!(self, "Going to broadcast Penalty Transaction {} claiming revoked {} output {} from {} with new feerate {}...", bumped_tx.txid(), if !is_htlc { "to_local" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { "offered" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { "received" } else { "" }, outp.vout, outp.txid, new_feerate); + }, + &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => { + if !preimage.is_some() { bumped_tx.lock_time = *locktime }; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation + let sighash_parts = bip143::SighashComponents::new(&bumped_tx); + let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]); + let sig = self.secp_ctx.sign(&sighash, &key); + bumped_tx.input[i].witness.push(sig.serialize_der().to_vec()); + bumped_tx.input[i].witness[0].push(SigHashType::All as u8); + if let &Some(preimage) = preimage { + bumped_tx.input[i].witness.push(preimage.clone().0.to_vec()); + } else { + bumped_tx.input[i].witness.push(vec![]); + } + bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); + log_trace!(self, "Going to broadcast Claim Transaction {} claiming remote {} htlc output {} from {} with new feerate {}...", bumped_tx.txid(), if preimage.is_some() { "offered" } else { "received" }, outp.vout, outp.txid, new_feerate); + }, + _ => unreachable!() + } + } + log_trace!(self, "...with timer {}", new_timer.unwrap()); + assert!(predicted_weight >= bumped_tx.get_weight()); + return Some((new_timer, new_feerate, bumped_tx)) + } else { + for (_, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() { + match per_outp_material { + &InputMaterial::LocalHTLC { ref preimage, ref amount } => { + let mut htlc_tx = None; + if let Some(ref mut local_commitment) = self.local_commitment { + if local_commitment.txid() == outp.txid { + self.key_storage.sign_htlc_transaction(local_commitment, outp.vout, *preimage, self.local_csv, &self.secp_ctx); + htlc_tx = local_commitment.htlc_with_valid_witness(outp.vout).clone(); + } + } + if let Some(ref mut prev_local_commitment) = self.prev_local_commitment { + if prev_local_commitment.txid() == outp.txid { + self.key_storage.sign_htlc_transaction(prev_local_commitment, outp.vout, *preimage, self.local_csv, &self.secp_ctx); + htlc_tx = prev_local_commitment.htlc_with_valid_witness(outp.vout).clone(); + } + } + if let Some(htlc_tx) = htlc_tx { + let feerate = (amount - htlc_tx.output[0].value) * 1000 / htlc_tx.get_weight() as u64; + // Timer set to $NEVER given we can't bump tx without anchor outputs + log_trace!(self, "Going to broadcast Local HTLC-{} claiming HTLC output {} from {}...", if preimage.is_some() { "Success" } else { "Timeout" }, outp.vout, outp.txid); + return Some((None, feerate, htlc_tx)); + } + return None; + }, + &InputMaterial::Funding {} => { + let signed_tx = self.get_fully_signed_local_tx().unwrap(); + // Timer set to $NEVER given we can't bump tx without anchor outputs + log_trace!(self, "Going to broadcast Local Transaction {} claiming funding output {} from {}...", signed_tx.txid(), outp.vout, outp.txid); + return Some((None, self.local_commitment.as_ref().unwrap().feerate_per_kw, signed_tx)); } - bumped_tx.input[i].witness.push(witness_script.clone().into_bytes()); - log_trace!(self, "Going to broadcast Claim Transaction {} claiming remote {} htlc output {} from {} with new feerate {}...", bumped_tx.txid(), if preimage.is_some() { "offered" } else { "received" }, outp.vout, outp.txid, new_feerate); - }, - &InputMaterial::LocalHTLC { .. } => { - //TODO : Given that Local Commitment Transaction and HTLC-Timeout/HTLC-Success are counter-signed by peer, we can't - // RBF them. Need a Lightning specs change and package relay modification : - // https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-November/016518.html - return None; + _ => unreachable!() } } } - log_trace!(self, "...with timer {}", new_timer); - assert!(predicted_weight >= bumped_tx.get_weight()); - Some((new_timer, new_feerate, bumped_tx)) + None } pub(super) fn block_connected(&mut self, txn_matched: &[&Transaction], claimable_outpoints: Vec, height: u32, broadcaster: B, fee_estimator: F) @@ -519,23 +575,23 @@ impl OnchainTxHandler { // Generate claim transactions and track them to bump if necessary at // height timer expiration (i.e in how many blocks we're going to take action). - for claim in new_claims { - let mut claim_material = ClaimTxBumpMaterial { height_timer: 0, feerate_previous: 0, soonest_timelock: claim.0, per_input_material: claim.1.clone() }; + for (soonest_timelock, claim) in new_claims.drain(..) { + let mut claim_material = ClaimTxBumpMaterial { height_timer: None, feerate_previous: 0, soonest_timelock, per_input_material: claim }; if let Some((new_timer, new_feerate, tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator) { claim_material.height_timer = new_timer; claim_material.feerate_previous = new_feerate; let txid = tx.txid(); - self.pending_claim_requests.insert(txid, claim_material); - for k in claim.1.keys() { + for k in claim_material.per_input_material.keys() { log_trace!(self, "Registering claiming request for {}:{}", k.txid, k.vout); self.claimable_outpoints.insert(k.clone(), (txid, height)); } + self.pending_claim_requests.insert(txid, claim_material); log_trace!(self, "Broadcast onchain {}", log_tx!(tx)); broadcaster.broadcast_transaction(&tx); } } - let mut bump_candidates = HashSet::new(); + let mut bump_candidates = HashMap::new(); for tx in txn_matched { // Scan all input to verify is one of the outpoint spent is of interest for us let mut claimed_outputs_material = Vec::new(); @@ -592,7 +648,7 @@ impl OnchainTxHandler { } //TODO: recompute soonest_timelock to avoid wasting a bit on fees if at_least_one_drop { - bump_candidates.insert(first_claim_txid_height.0.clone()); + bump_candidates.insert(first_claim_txid_height.0.clone(), claim_material.clone()); } } break; //No need to iterate further, either tx is our or their @@ -638,27 +694,23 @@ impl OnchainTxHandler { // Check if any pending claim request must be rescheduled for (first_claim_txid, ref claim_data) in self.pending_claim_requests.iter() { - if claim_data.height_timer == height { - bump_candidates.insert(*first_claim_txid); + if let Some(h) = claim_data.height_timer { + if h == height { + bump_candidates.insert(*first_claim_txid, (*claim_data).clone()); + } } } // Build, bump and rebroadcast tx accordingly log_trace!(self, "Bumping {} candidates", bump_candidates.len()); - for first_claim_txid in bump_candidates.iter() { - if let Some((new_timer, new_feerate)) = { - if let Some(claim_material) = self.pending_claim_requests.get(first_claim_txid) { - if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator) { - log_trace!(self, "Broadcast onchain {}", log_tx!(bump_tx)); - broadcaster.broadcast_transaction(&bump_tx); - Some((new_timer, new_feerate)) - } else { None } - } else { unreachable!(); } - } { + for (first_claim_txid, claim_material) in bump_candidates.iter() { + if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator) { + log_trace!(self, "Broadcast onchain {}", log_tx!(bump_tx)); + broadcaster.broadcast_transaction(&bump_tx); if let Some(claim_material) = self.pending_claim_requests.get_mut(first_claim_txid) { claim_material.height_timer = new_timer; claim_material.feerate_previous = new_feerate; - } else { unreachable!(); } + } } } } @@ -709,4 +761,51 @@ impl OnchainTxHandler { self.pending_claim_requests.remove(&req); } } + + pub(super) fn provide_latest_local_tx(&mut self, tx: LocalCommitmentTransaction) -> Result<(), ()> { + // To prevent any unsafe state discrepancy between offchain and onchain, once local + // commitment transaction has been signed due to an event (either block height for + // HTLC-timeout or channel force-closure), don't allow any further update of local + // commitment transaction view to avoid delivery of revocation secret to counterparty + // for the aformentionned signed transaction. + if let Some(ref local_commitment) = self.local_commitment { + if local_commitment.has_local_sig() { return Err(()) } + } + self.prev_local_commitment = self.local_commitment.take(); + self.local_commitment = Some(tx); + Ok(()) + } + + //TODO: getting lastest local transactions should be infaillible and result in us "force-closing the channel", but we may + // have empty local 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(super) fn get_fully_signed_local_tx(&mut self) -> Option { + if let Some(ref mut local_commitment) = self.local_commitment { + self.key_storage.sign_local_commitment(local_commitment, &self.secp_ctx); + return Some(local_commitment.with_valid_witness().clone()); + } + None + } + + #[cfg(test)] + pub(super) fn get_fully_signed_copy_local_tx(&mut self) -> Option { + if let Some(ref mut local_commitment) = self.local_commitment { + let mut local_commitment = local_commitment.clone(); + self.key_storage.unsafe_sign_local_commitment(&mut local_commitment, &self.secp_ctx); + return Some(local_commitment.with_valid_witness().clone()); + } + None + } + + pub(super) fn get_fully_signed_htlc_tx(&mut self, txid: Sha256dHash, htlc_index: u32, preimage: Option) -> Option { + //TODO: store preimage in OnchainTxHandler + if let Some(ref mut local_commitment) = self.local_commitment { + if local_commitment.txid() == txid { + self.key_storage.sign_htlc_transaction(local_commitment, htlc_index, preimage, self.local_csv, &self.secp_ctx); + return local_commitment.htlc_with_valid_witness(htlc_index).clone(); + } + } + None + } }