X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchan_utils.rs;h=370c0cc8edfe6737f3f1d65f5dab59ea688ee854;hb=d629a7edb7241eee7fde9f5ccdf1c481d2d6297b;hp=80dd872a9de9cec9e6e3277cf0ccab8c4b2d9705;hpb=3efcbab5d42d5c2cd7d37ce18a8bcca211569bb8;p=rust-lightning diff --git a/lightning/src/ln/chan_utils.rs b/lightning/src/ln/chan_utils.rs index 80dd872a..370c0cc8 100644 --- a/lightning/src/ln/chan_utils.rs +++ b/lightning/src/ln/chan_utils.rs @@ -39,11 +39,25 @@ use util::transaction_utils::sort_outputs; use ln::channel::{INITIAL_COMMITMENT_NUMBER, ANCHOR_OUTPUT_VALUE_SATOSHI}; use core::ops::Deref; use chain; +use util::crypto::sign; pub(crate) const MAX_HTLCS: u16 = 483; -pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703; -pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663; +/// Gets the weight for an HTLC-Success transaction. +#[inline] +pub fn htlc_success_tx_weight(opt_anchors: bool) -> u64 { + const HTLC_SUCCESS_TX_WEIGHT: u64 = 703; + const HTLC_SUCCESS_ANCHOR_TX_WEIGHT: u64 = 706; + if opt_anchors { HTLC_SUCCESS_ANCHOR_TX_WEIGHT } else { HTLC_SUCCESS_TX_WEIGHT } +} + +/// Gets the weight for an HTLC-Timeout transaction. +#[inline] +pub fn htlc_timeout_tx_weight(opt_anchors: bool) -> u64 { + const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663; + const HTLC_TIMEOUT_ANCHOR_TX_WEIGHT: u64 = 666; + if opt_anchors { HTLC_TIMEOUT_ANCHOR_TX_WEIGHT } else { HTLC_TIMEOUT_TX_WEIGHT } +} #[derive(PartialEq)] pub(crate) enum HTLCType { @@ -127,10 +141,10 @@ pub fn build_closing_transaction(to_holder_value_sat: u64, to_counterparty_value /// Implements the per-commitment secret storage scheme from /// [BOLT 3](https://github.com/lightningnetwork/lightning-rfc/blob/dcbf8583976df087c79c3ce0b535311212e6812d/03-transactions.md#efficient-per-commitment-secret-storage). /// -/// Allows us to keep track of all of the revocation secrets of counterarties in just 50*32 bytes +/// Allows us to keep track of all of the revocation secrets of our counterparty in just 50*32 bytes /// or so. #[derive(Clone)] -pub(crate) struct CounterpartyCommitmentSecrets { +pub struct CounterpartyCommitmentSecrets { old_secrets: [([u8; 32], u64); 49], } @@ -146,7 +160,8 @@ impl PartialEq for CounterpartyCommitmentSecrets { } impl CounterpartyCommitmentSecrets { - pub(crate) fn new() -> Self { + /// Creates a new empty `CounterpartyCommitmentSecrets` structure. + pub fn new() -> Self { Self { old_secrets: [([0; 32], 1 << 48); 49], } } @@ -160,7 +175,9 @@ impl CounterpartyCommitmentSecrets { 48 } - pub(crate) fn get_min_seen_secret(&self) -> u64 { + /// Returns the minimum index of all stored secrets. Note that indexes start + /// at 1 << 48 and get decremented by one for each new secret. + pub fn get_min_seen_secret(&self) -> u64 { //TODO This can be optimized? let mut min = 1 << 48; for &(_, idx) in self.old_secrets.iter() { @@ -184,7 +201,9 @@ impl CounterpartyCommitmentSecrets { res } - pub(crate) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> { + /// Inserts the `secret` at `idx`. Returns `Ok(())` if the secret + /// was generated in accordance with BOLT 3 and is consistent with previous secrets. + pub fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), ()> { let pos = Self::place_secret(idx); for i in 0..pos { let (old_secret, old_idx) = self.old_secrets[i as usize]; @@ -199,8 +218,9 @@ impl CounterpartyCommitmentSecrets { Ok(()) } - /// Can only fail if idx is < get_min_seen_secret - pub(crate) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> { + /// Returns the secret at `idx`. + /// Returns `None` if `idx` is < [`CounterpartyCommitmentSecrets::get_min_seen_secret`]. + pub fn get_secret(&self, idx: u64) -> Option<[u8; 32]> { for i in 0..self.old_secrets.len() { if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 { return Some(Self::derive_secret(self.old_secrets[i].0, i as u8, idx)) @@ -586,7 +606,7 @@ pub fn make_funding_redeemscript(broadcaster: &PublicKey, countersignatory: &Pub /// /// Panics if htlc.transaction_output_index.is_none() (as such HTLCs do not appear in the /// commitment transaction). -pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { +pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, opt_anchors: bool, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction { let mut txins: Vec = Vec::new(); txins.push(TxIn { previous_output: OutPoint { @@ -594,15 +614,16 @@ pub fn build_htlc_transaction(commitment_txid: &Txid, feerate_per_kw: u32, conte vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"), }, script_sig: Script::new(), - sequence: 0, + sequence: if opt_anchors { 1 } else { 0 }, witness: Vec::new(), }); - let total_fee = if htlc.offered { - feerate_per_kw as u64 * HTLC_TIMEOUT_TX_WEIGHT / 1000 - } else { - feerate_per_kw as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000 - }; + let weight = if htlc.offered { + htlc_timeout_tx_weight(opt_anchors) + } else { + htlc_success_tx_weight(opt_anchors) + }; + let total_fee = feerate_per_kw as u64 * weight / 1000; let mut txouts: Vec = Vec::new(); txouts.push(TxOut { @@ -636,7 +657,7 @@ pub(crate) fn get_to_countersignatory_with_anchors_redeemscript(payment_point: & /// <> /// (empty vector required to satisfy compliance with MINIMALIF-standard rule) #[inline] -pub(crate) fn get_anchor_redeemscript(funding_pubkey: &PublicKey) -> Script { +pub fn get_anchor_redeemscript(funding_pubkey: &PublicKey) -> Script { Builder::new().push_slice(&funding_pubkey.serialize()[..]) .push_opcode(opcodes::all::OP_CHECKSIG) .push_opcode(opcodes::all::OP_IFDUP) @@ -774,6 +795,11 @@ impl<'a> DirectedChannelTransactionParameters<'a> { pub fn funding_outpoint(&self) -> OutPoint { self.inner.funding_outpoint.unwrap().into_bitcoin_outpoint() } + + /// Whether to use anchors for this channel + pub fn opt_anchors(&self) -> bool { + self.inner.opt_anchors.is_some() + } } /// Information needed to build and sign a holder's commitment transaction. @@ -816,7 +842,7 @@ impl HolderCommitmentTransaction { pub fn dummy() -> Self { let secp_ctx = Secp256k1::new(); let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()); - let dummy_sig = secp_ctx.sign(&secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap()); + let dummy_sig = sign(&secp_ctx, &secp256k1::Message::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap()); let keys = TxCreationKeys { per_commitment_point: dummy_key.clone(), @@ -911,7 +937,7 @@ impl BuiltCommitmentTransaction { /// because we are about to broadcast a holder transaction. pub fn sign(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1) -> Signature { let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis); - secp_ctx.sign(&sighash, funding_key) + sign(secp_ctx, &sighash, funding_key) } } @@ -920,6 +946,7 @@ impl BuiltCommitmentTransaction { /// /// This class can be used inside a signer implementation to generate a signature given the relevant /// secret key. +#[derive(Clone, Hash, PartialEq)] pub struct ClosingTransaction { to_holder_value_sat: u64, to_counterparty_value_sat: u64, @@ -1034,7 +1061,7 @@ impl<'a> TrustedClosingTransaction<'a> { /// because we are about to broadcast a holder transaction. pub fn sign(&self, funding_key: &SecretKey, funding_redeemscript: &Script, channel_value_satoshis: u64, secp_ctx: &Secp256k1) -> Signature { let sighash = self.get_sighash_all(funding_redeemscript, channel_value_satoshis); - secp_ctx.sign(&sighash, funding_key) + sign(secp_ctx, &sighash, funding_key) } } @@ -1225,7 +1252,7 @@ impl CommitmentTransaction { if let &Some(ref b_htlcout) = b { a_htlcout.cltv_expiry.cmp(&b_htlcout.cltv_expiry) // Note that due to hash collisions, we have to have a fallback comparison - // here for fuzztarget mode (otherwise at least chanmon_fail_consistency + // here for fuzzing mode (otherwise at least chanmon_fail_consistency // may fail)! .then(a_htlcout.payment_hash.0.cmp(&b_htlcout.payment_hash.0)) // For non-HTLC outputs, if they're copying our SPK we don't really care if we @@ -1373,6 +1400,8 @@ impl<'a> TrustedCommitmentTransaction<'a> { /// which HTLCOutputInCommitment::transaction_output_index.is_some()). /// /// The returned Vec has one entry for each HTLC, and in the same order. + /// + /// This function is only valid in the holder commitment context, it always uses SigHashType::All. pub fn get_htlc_sigs(&self, htlc_base_key: &SecretKey, channel_parameters: &DirectedChannelTransactionParameters, secp_ctx: &Secp256k1) -> Result, ()> { let inner = self.inner; let keys = &inner.keys; @@ -1382,12 +1411,12 @@ impl<'a> TrustedCommitmentTransaction<'a> { for this_htlc in inner.htlcs.iter() { assert!(this_htlc.transaction_output_index.is_some()); - let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key); + let htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, self.opt_anchors(), &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key); let sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, this_htlc.amount_msat / 1000, SigHashType::All)[..]); - ret.push(secp_ctx.sign(&sighash, &holder_htlc_key)); + ret.push(sign(secp_ctx, &sighash, &holder_htlc_key)); } Ok(ret) } @@ -1404,16 +1433,18 @@ impl<'a> TrustedCommitmentTransaction<'a> { // Further, we should never be provided the preimage for an HTLC-Timeout transaction. if this_htlc.offered && preimage.is_some() { unreachable!(); } - let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key); + let mut htlc_tx = build_htlc_transaction(&txid, inner.feerate_per_kw, channel_parameters.contest_delay(), &this_htlc, self.opt_anchors(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc, self.opt_anchors(), &keys.broadcaster_htlc_key, &keys.countersignatory_htlc_key, &keys.revocation_key); + let sighashtype = if self.opt_anchors() { SigHashType::SinglePlusAnyoneCanPay } else { SigHashType::All }; + // First push the multisig dummy, note that due to BIP147 (NULLDUMMY) it must be a zero-length element. htlc_tx.input[0].witness.push(Vec::new()); htlc_tx.input[0].witness.push(counterparty_signature.serialize_der().to_vec()); htlc_tx.input[0].witness.push(signature.serialize_der().to_vec()); - htlc_tx.input[0].witness[1].push(SigHashType::All as u8); + htlc_tx.input[0].witness[1].push(sighashtype as u8); htlc_tx.input[0].witness[2].push(SigHashType::All as u8); if this_htlc.offered { @@ -1475,6 +1506,7 @@ mod tests { use chain::keysinterface::{KeysInterface, BaseSign}; use bitcoin::Network; use ln::PaymentHash; + use bitcoin::hashes::hex::ToHex; #[test] fn test_anchors() { @@ -1578,6 +1610,10 @@ mod tests { assert_eq!(tx.built.transaction.output.len(), 3); assert_eq!(tx.built.transaction.output[0].script_pubkey, get_htlc_redeemscript(&received_htlc, false, &keys).to_v0_p2wsh()); assert_eq!(tx.built.transaction.output[1].script_pubkey, get_htlc_redeemscript(&offered_htlc, false, &keys).to_v0_p2wsh()); + assert_eq!(get_htlc_redeemscript(&received_htlc, false, &keys).to_v0_p2wsh().to_hex(), + "002085cf52e41ba7c099a39df504e7b61f6de122971ceb53b06731876eaeb85e8dc5"); + assert_eq!(get_htlc_redeemscript(&offered_htlc, false, &keys).to_v0_p2wsh().to_hex(), + "002049f0736bb335c61a04d2623a24df878a7592a3c51fa7258d41b2c85318265e73"); // Generate broadcaster output and received and offered HTLC outputs, with anchors channel_parameters.opt_anchors = Some(()); @@ -1593,6 +1629,10 @@ mod tests { assert_eq!(tx.built.transaction.output.len(), 5); assert_eq!(tx.built.transaction.output[2].script_pubkey, get_htlc_redeemscript(&received_htlc, true, &keys).to_v0_p2wsh()); assert_eq!(tx.built.transaction.output[3].script_pubkey, get_htlc_redeemscript(&offered_htlc, true, &keys).to_v0_p2wsh()); + assert_eq!(get_htlc_redeemscript(&received_htlc, true, &keys).to_v0_p2wsh().to_hex(), + "002067114123af3f95405bae4fd930fc95de03e3c86baaee8b2dd29b43dd26cf613c"); + assert_eq!(get_htlc_redeemscript(&offered_htlc, true, &keys).to_v0_p2wsh().to_hex(), + "0020a06e3b0d4fcf704f2b9c41e16a70099e39989466c3142b8573a1154542f28f57"); } #[test]