use ln::{PaymentHash, PaymentPreimage};
use ln::msgs::DecodeError;
use util::ser::{Readable, Writeable, Writer};
-use util::byte_utils;
+use util::{byte_utils, transaction_utils};
use bitcoin::hash_types::WPubkeyHash;
use bitcoin::secp256k1::key::{SecretKey, PublicKey};
use bitcoin::secp256k1::Error as SecpError;
use bitcoin::secp256k1;
+use io;
use prelude::*;
use core::cmp;
use ln::chan_utils;
use util::transaction_utils::sort_outputs;
-use ln::channel::INITIAL_COMMITMENT_NUMBER;
+use ln::channel::{INITIAL_COMMITMENT_NUMBER, ANCHOR_OUTPUT_VALUE_SATOSHI};
use core::ops::Deref;
use chain;
res
}
+/// Build a closing transaction
+pub fn build_closing_transaction(value_to_holder: u64, value_to_counterparty: u64, holder_shutdown_script: Script, counterparty_shutdown_script: Script, funding_outpoint: OutPoint) -> Transaction {
+ let txins = {
+ let mut ins: Vec<TxIn> = Vec::new();
+ ins.push(TxIn {
+ previous_output: funding_outpoint,
+ script_sig: Script::new(),
+ sequence: 0xffffffff,
+ witness: Vec::new(),
+ });
+ ins
+ };
+
+ let mut txouts: Vec<(TxOut, ())> = Vec::new();
+
+ if value_to_counterparty > 0 {
+ txouts.push((TxOut {
+ script_pubkey: counterparty_shutdown_script,
+ value: value_to_counterparty
+ }, ()));
+ }
+
+ if value_to_holder > 0 {
+ txouts.push((TxOut {
+ script_pubkey: holder_shutdown_script,
+ value: value_to_holder
+ }, ()));
+ }
+
+ transaction_utils::sort_outputs(&mut txouts, |_, _| { cmp::Ordering::Equal }); // Ordering doesnt matter if they used our pubkey...
+
+ let mut outputs: Vec<TxOut> = Vec::new();
+ for out in txouts.drain(..) {
+ outputs.push(out.0);
+ }
+
+ Transaction {
+ version: 2,
+ lock_time: 0,
+ input: txins,
+ output: outputs,
+ }
+}
+
/// 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).
///
}
impl Writeable for CounterpartyCommitmentSecrets {
- fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+ fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
for &(ref secret, ref idx) in self.old_secrets.iter() {
writer.write_all(secret)?;
writer.write_all(&byte_utils::be64_to_array(*idx))?;
}
- write_tlv_fields!(writer, {}, {});
+ write_tlv_fields!(writer, {});
Ok(())
}
}
impl Readable for CounterpartyCommitmentSecrets {
- fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+ fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
let mut old_secrets = [([0; 32], 1 << 48); 49];
for &mut (ref mut secret, ref mut idx) in old_secrets.iter_mut() {
*secret = Readable::read(reader)?;
*idx = Readable::read(reader)?;
}
- read_tlv_fields!(reader, {}, {});
+ read_tlv_fields!(reader, {});
Ok(Self { old_secrets })
}
}
}
impl_writeable_tlv_based!(TxCreationKeys, {
- (0, per_commitment_point),
- (2, revocation_key),
- (4, broadcaster_htlc_key),
- (6, countersignatory_htlc_key),
- (8, broadcaster_delayed_payment_key),
-}, {}, {});
+ (0, per_commitment_point, required),
+ (2, revocation_key, required),
+ (4, broadcaster_htlc_key, required),
+ (6, countersignatory_htlc_key, required),
+ (8, broadcaster_delayed_payment_key, required),
+});
/// One counterparty's public keys which do not change over the life of a channel.
#[derive(Clone, PartialEq)]
}
impl_writeable_tlv_based!(ChannelPublicKeys, {
- (0, funding_pubkey),
- (2, revocation_basepoint),
- (4, payment_point),
- (6, delayed_payment_basepoint),
- (8, htlc_basepoint),
-}, {}, {});
+ (0, funding_pubkey, required),
+ (2, revocation_basepoint, required),
+ (4, payment_point, required),
+ (6, delayed_payment_basepoint, required),
+ (8, htlc_basepoint, required),
+});
impl TxCreationKeys {
/// Create per-state keys from channel base points and the per-commitment point.
}
impl_writeable_tlv_based!(HTLCOutputInCommitment, {
- (0, offered),
- (2, amount_msat),
- (4, cltv_expiry),
- (6, payment_hash),
-}, {
- (8, transaction_output_index)
-}, {});
+ (0, offered, required),
+ (2, amount_msat, required),
+ (4, cltv_expiry, required),
+ (6, payment_hash, required),
+ (8, transaction_output_index, option),
+});
#[inline]
pub(crate) fn get_htlc_redeemscript_with_explicit_keys(htlc: &HTLCOutputInCommitment, broadcaster_htlc_key: &PublicKey, countersignatory_htlc_key: &PublicKey, revocation_key: &PublicKey) -> Script {
}.push_opcode(opcodes::all::OP_PUSHNUM_2).push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
}
-/// panics if htlc.transaction_output_index.is_none()!
-pub fn build_htlc_transaction(prev_hash: &Txid, feerate_per_kw: u32, contest_delay: u16, htlc: &HTLCOutputInCommitment, broadcaster_delayed_payment_key: &PublicKey, revocation_key: &PublicKey) -> Transaction {
+/// Builds an unsigned HTLC-Success or HTLC-Timeout transaction from the given channel and HTLC
+/// parameters. This is used by [`TrustedCommitmentTransaction::get_htlc_sigs`] to fetch the
+/// transaction which needs signing, and can be used to construct an HTLC transaction which is
+/// broadcastable given a counterparty HTLC signature.
+///
+/// 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 {
let mut txins: Vec<TxIn> = Vec::new();
txins.push(TxIn {
previous_output: OutPoint {
- txid: prev_hash.clone(),
+ txid: commitment_txid.clone(),
vout: htlc.transaction_output_index.expect("Can't build an HTLC transaction for a dust output"),
},
script_sig: Script::new(),
}
}
+/// Gets the witnessScript for an anchor output from the funding public key.
+/// The witness in the spending input must be:
+/// <BIP 143 funding_signature>
+/// After 16 blocks of confirmation, an alternative satisfying witness could be:
+/// <>
+/// (empty vector required to satisfy compliance with MINIMALIF-standard rule)
+#[inline]
+pub(crate) 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)
+ .push_opcode(opcodes::all::OP_NOTIF)
+ .push_int(16)
+ .push_opcode(opcodes::all::OP_CSV)
+ .push_opcode(opcodes::all::OP_ENDIF)
+ .into_script()
+}
+
/// Per-channel data used to build transactions in conjunction with the per-commitment data (CommitmentTransaction).
/// The fields are organized by holder/counterparty.
///
}
impl_writeable_tlv_based!(CounterpartyChannelTransactionParameters, {
- (0, pubkeys),
- (2, selected_contest_delay),
-}, {}, {});
+ (0, pubkeys, required),
+ (2, selected_contest_delay, required),
+});
impl_writeable_tlv_based!(ChannelTransactionParameters, {
- (0, holder_pubkeys),
- (2, holder_selected_contest_delay),
- (4, is_outbound_from_holder),
-}, {
- (6, counterparty_parameters),
- (8, funding_outpoint),
-}, {});
+ (0, holder_pubkeys, required),
+ (2, holder_selected_contest_delay, required),
+ (4, is_outbound_from_holder, required),
+ (6, counterparty_parameters, option),
+ (8, funding_outpoint, option),
+});
/// Static channel fields used to build transactions given per-commitment fields, organized by
/// broadcaster/countersignatory.
}
impl_writeable_tlv_based!(HolderCommitmentTransaction, {
- (0, inner),
- (2, counterparty_sig),
- (4, holder_sig_first),
-}, {}, {
- (6, counterparty_htlc_sigs),
+ (0, inner, required),
+ (2, counterparty_sig, required),
+ (4, holder_sig_first, required),
+ (6, counterparty_htlc_sigs, vec_type),
});
impl HolderCommitmentTransaction {
funding_outpoint: Some(chain::transaction::OutPoint { txid: Default::default(), index: 0 })
};
let mut htlcs_with_aux: Vec<(_, ())> = Vec::new();
- let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, keys, 0, &mut htlcs_with_aux, &channel_parameters.as_counterparty_broadcastable());
+ let inner = CommitmentTransaction::new_with_auxiliary_htlc_data(0, 0, 0, false, dummy_key.clone(), dummy_key.clone(), keys, 0, &mut htlcs_with_aux, &channel_parameters.as_counterparty_broadcastable());
HolderCommitmentTransaction {
inner,
counterparty_sig: dummy_sig,
}
impl_writeable_tlv_based!(BuiltCommitmentTransaction, {
- (0, transaction),
- (2, txid)
-}, {}, {});
+ (0, transaction, required),
+ (2, txid, required),
+});
impl BuiltCommitmentTransaction {
/// Get the SIGHASH_ALL sighash value of the transaction.
to_countersignatory_value_sat: u64,
feerate_per_kw: u32,
htlcs: Vec<HTLCOutputInCommitment>,
+ // A boolean that is serialization backwards-compatible
+ opt_anchors: Option<()>,
// A cache of the parties' pubkeys required to construct the transaction, see doc for trust()
keys: TxCreationKeys,
// For access to the pre-built transaction, see doc for trust()
self.to_countersignatory_value_sat == o.to_countersignatory_value_sat &&
self.feerate_per_kw == o.feerate_per_kw &&
self.htlcs == o.htlcs &&
+ self.opt_anchors == o.opt_anchors &&
self.keys == o.keys;
if eq {
debug_assert_eq!(self.built.transaction, o.built.transaction);
}
impl_writeable_tlv_based!(CommitmentTransaction, {
- (0, commitment_number),
- (2, to_broadcaster_value_sat),
- (4, to_countersignatory_value_sat),
- (6, feerate_per_kw),
- (8, keys),
- (10, built),
-}, {}, {
- (12, htlcs),
+ (0, commitment_number, required),
+ (2, to_broadcaster_value_sat, required),
+ (4, to_countersignatory_value_sat, required),
+ (6, feerate_per_kw, required),
+ (8, keys, required),
+ (10, built, required),
+ (12, htlcs, vec_type),
+ (14, opt_anchors, option),
});
impl CommitmentTransaction {
/// Only include HTLCs that are above the dust limit for the channel.
///
/// (C-not exported) due to the generic though we likely should expose a version without
- pub fn new_with_auxiliary_htlc_data<T>(commitment_number: u64, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, keys: TxCreationKeys, feerate_per_kw: u32, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> CommitmentTransaction {
+ pub fn new_with_auxiliary_htlc_data<T>(commitment_number: u64, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, opt_anchors: bool, broadcaster_funding_key: PublicKey, countersignatory_funding_key: PublicKey, keys: TxCreationKeys, feerate_per_kw: u32, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> CommitmentTransaction {
// Sort outputs and populate output indices while keeping track of the auxiliary data
- let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters).unwrap();
+ let (outputs, htlcs) = Self::internal_build_outputs(&keys, to_broadcaster_value_sat, to_countersignatory_value_sat, htlcs_with_aux, channel_parameters, opt_anchors, &broadcaster_funding_key, &countersignatory_funding_key).unwrap();
let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(commitment_number, channel_parameters);
let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
to_countersignatory_value_sat,
feerate_per_kw,
htlcs,
+ opt_anchors: if opt_anchors { Some(()) } else { None },
keys,
built: BuiltCommitmentTransaction {
transaction,
}
}
- fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters) -> Result<BuiltCommitmentTransaction, ()> {
+ fn internal_rebuild_transaction(&self, keys: &TxCreationKeys, channel_parameters: &DirectedChannelTransactionParameters, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result<BuiltCommitmentTransaction, ()> {
let (obscured_commitment_transaction_number, txins) = Self::internal_build_inputs(self.commitment_number, channel_parameters);
let mut htlcs_with_aux = self.htlcs.iter().map(|h| (h.clone(), ())).collect();
- let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters)?;
+ let (outputs, _) = Self::internal_build_outputs(keys, self.to_broadcaster_value_sat, self.to_countersignatory_value_sat, &mut htlcs_with_aux, channel_parameters, self.opt_anchors.is_some(), broadcaster_funding_key, countersignatory_funding_key)?;
let transaction = Self::make_transaction(obscured_commitment_transaction_number, txins, outputs);
let txid = transaction.txid();
// - initial sorting of outputs / HTLCs in the constructor, in which case T is auxiliary data the
// caller needs to have sorted together with the HTLCs so it can keep track of the output index
// - building of a bitcoin transaction during a verify() call, in which case T is just ()
- fn internal_build_outputs<T>(keys: &TxCreationKeys, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters) -> Result<(Vec<TxOut>, Vec<HTLCOutputInCommitment>), ()> {
+ fn internal_build_outputs<T>(keys: &TxCreationKeys, to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, htlcs_with_aux: &mut Vec<(HTLCOutputInCommitment, T)>, channel_parameters: &DirectedChannelTransactionParameters, opt_anchors: bool, broadcaster_funding_key: &PublicKey, countersignatory_funding_key: &PublicKey) -> Result<(Vec<TxOut>, Vec<HTLCOutputInCommitment>), ()> {
let countersignatory_pubkeys = channel_parameters.countersignatory_pubkeys();
let contest_delay = channel_parameters.contest_delay();
));
}
+ if opt_anchors {
+ if to_broadcaster_value_sat > 0 || !htlcs_with_aux.is_empty() {
+ let anchor_script = get_anchor_redeemscript(broadcaster_funding_key);
+ txouts.push((
+ TxOut {
+ script_pubkey: anchor_script.to_v0_p2wsh(),
+ value: ANCHOR_OUTPUT_VALUE_SATOSHI,
+ },
+ None,
+ ));
+ }
+
+ if to_countersignatory_value_sat > 0 || !htlcs_with_aux.is_empty() {
+ let anchor_script = get_anchor_redeemscript(countersignatory_funding_key);
+ txouts.push((
+ TxOut {
+ script_pubkey: anchor_script.to_v0_p2wsh(),
+ value: ANCHOR_OUTPUT_VALUE_SATOSHI,
+ },
+ None,
+ ));
+ }
+ }
+
let mut htlcs = Vec::with_capacity(htlcs_with_aux.len());
for (htlc, _) in htlcs_with_aux {
let script = chan_utils::get_htlc_redeemscript(&htlc, &keys);
if keys != self.keys {
return Err(());
}
- let tx = self.internal_rebuild_transaction(&keys, channel_parameters)?;
+ let tx = self.internal_rebuild_transaction(&keys, channel_parameters, &broadcaster_keys.funding_pubkey, &countersignatory_keys.funding_pubkey)?;
if self.built.transaction != tx.transaction || self.built.txid != tx.txid {
return Err(());
}
}
}
-/// Get the transaction number obscure factor
+/// Commitment transaction numbers which appear in the transactions themselves are XOR'd with a
+/// shared secret first. This prevents on-chain observers from discovering how many commitment
+/// transactions occurred in a channel before it was closed.
+///
+/// This function gets the shared secret from relevant channel public keys and can be used to
+/// "decrypt" the commitment transaction number given a commitment transaction on-chain.
pub fn get_commitment_transaction_number_obscure_factor(
broadcaster_payment_basepoint: &PublicKey,
countersignatory_payment_basepoint: &PublicKey,
#[cfg(test)]
mod tests {
use super::CounterpartyCommitmentSecrets;
- use hex;
+ use ::{hex, chain};
use prelude::*;
+ use ln::chan_utils::{CommitmentTransaction, TxCreationKeys, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, HTLCOutputInCommitment};
+ use bitcoin::secp256k1::{PublicKey, SecretKey, Secp256k1};
+ use util::test_utils;
+ use chain::keysinterface::{KeysInterface, BaseSign};
+ use bitcoin::Network;
+ use ln::PaymentHash;
+
+ #[test]
+ fn test_anchors() {
+ let secp_ctx = Secp256k1::new();
+
+ let seed = [42; 32];
+ let network = Network::Testnet;
+ let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
+ let signer = keys_provider.get_channel_signer(false, 3000);
+ let counterparty_signer = keys_provider.get_channel_signer(false, 3000);
+ let delayed_payment_base = &signer.pubkeys().delayed_payment_basepoint;
+ let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
+ let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
+ let htlc_basepoint = &signer.pubkeys().htlc_basepoint;
+ let holder_pubkeys = signer.pubkeys();
+ let counterparty_pubkeys = counterparty_signer.pubkeys();
+ let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
+ let channel_parameters = ChannelTransactionParameters {
+ holder_pubkeys: holder_pubkeys.clone(),
+ holder_selected_contest_delay: 0,
+ is_outbound_from_holder: false,
+ counterparty_parameters: Some(CounterpartyChannelTransactionParameters { pubkeys: counterparty_pubkeys.clone(), selected_contest_delay: 0 }),
+ funding_outpoint: Some(chain::transaction::OutPoint { txid: Default::default(), index: 0 })
+ };
+
+ let mut htlcs_with_aux: Vec<(_, ())> = Vec::new();
+
+ // Generate broadcaster and counterparty outputs
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(
+ 0, 1000, 2000,
+ false,
+ holder_pubkeys.funding_pubkey,
+ counterparty_pubkeys.funding_pubkey,
+ keys.clone(), 1,
+ &mut htlcs_with_aux, &channel_parameters.as_holder_broadcastable()
+ );
+ assert_eq!(tx.built.transaction.output.len(), 2);
+
+ // Generate broadcaster and counterparty outputs as well as two anchors
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(
+ 0, 1000, 2000,
+ true,
+ holder_pubkeys.funding_pubkey,
+ counterparty_pubkeys.funding_pubkey,
+ keys.clone(), 1,
+ &mut htlcs_with_aux, &channel_parameters.as_holder_broadcastable()
+ );
+ assert_eq!(tx.built.transaction.output.len(), 4);
+
+ // Generate broadcaster output and anchor
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(
+ 0, 3000, 0,
+ true,
+ holder_pubkeys.funding_pubkey,
+ counterparty_pubkeys.funding_pubkey,
+ keys.clone(), 1,
+ &mut htlcs_with_aux, &channel_parameters.as_holder_broadcastable()
+ );
+ assert_eq!(tx.built.transaction.output.len(), 2);
+
+ // Generate counterparty output and anchor
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(
+ 0, 0, 3000,
+ true,
+ holder_pubkeys.funding_pubkey,
+ counterparty_pubkeys.funding_pubkey,
+ keys.clone(), 1,
+ &mut htlcs_with_aux, &channel_parameters.as_holder_broadcastable()
+ );
+ assert_eq!(tx.built.transaction.output.len(), 2);
+
+ // Generate broadcaster output, an HTLC output and two anchors
+ let payment_hash = PaymentHash([42; 32]);
+ let htlc_info = HTLCOutputInCommitment {
+ offered: false,
+ amount_msat: 1000000,
+ cltv_expiry: 100,
+ payment_hash,
+ transaction_output_index: None,
+ };
+
+ let tx = CommitmentTransaction::new_with_auxiliary_htlc_data(
+ 0, 3000, 0,
+ true,
+ holder_pubkeys.funding_pubkey,
+ counterparty_pubkeys.funding_pubkey,
+ keys.clone(), 1,
+ &mut vec![(htlc_info, ())], &channel_parameters.as_holder_broadcastable()
+ );
+ assert_eq!(tx.built.transaction.output.len(), 4);
+ }
#[test]
fn test_per_commitment_storage() {
projects / rust-lightning / blobdiff