X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fkeysinterface.rs;h=7be26634916fbaa5268d264528e7099953d6c03d;hb=cd4dc39a8c4732bea1a3221617f86e34dfb7efb8;hp=249a2f524604b4a64b28d2753abc78e79b369417;hpb=5d74cae6c5665a0bd917b24b4fcaf181ff6b5450;p=rust-lightning diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index 249a2f52..7be26634 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -34,12 +34,13 @@ use util::ser::{Writeable, Writer, Readable}; use chain::transaction::OutPoint; use ln::chan_utils; -use ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, HolderCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction}; +use ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, HolderCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction, ClosingTransaction}; use ln::msgs::UnsignedChannelAnnouncement; +use ln::script::ShutdownScript; -use std::collections::HashSet; -use std::sync::atomic::{AtomicUsize, Ordering}; -use std::io::Error; +use prelude::*; +use core::sync::atomic::{AtomicUsize, Ordering}; +use io::{self, Error}; use ln::msgs::{DecodeError, MAX_VALUE_MSAT}; /// Information about a spendable output to a P2WSH script. See @@ -72,6 +73,16 @@ impl DelayedPaymentOutputDescriptor { pub const MAX_WITNESS_LENGTH: usize = 1 + 73 + 1 + chan_utils::REVOKEABLE_REDEEMSCRIPT_MAX_LENGTH + 1; } +impl_writeable_tlv_based!(DelayedPaymentOutputDescriptor, { + (0, outpoint, required), + (2, per_commitment_point, required), + (4, to_self_delay, required), + (6, output, required), + (8, revocation_pubkey, required), + (10, channel_keys_id, required), + (12, channel_value_satoshis, required), +}); + /// Information about a spendable output to our "payment key". See /// SpendableOutputDescriptor::StaticPaymentOutput for more details on how to spend this. #[derive(Clone, Debug, PartialEq)] @@ -93,6 +104,12 @@ impl StaticPaymentOutputDescriptor { // redeemscript push length. pub const MAX_WITNESS_LENGTH: usize = 1 + 73 + 34; } +impl_writeable_tlv_based!(StaticPaymentOutputDescriptor, { + (0, outpoint, required), + (2, output, required), + (4, channel_keys_id, required), + (6, channel_value_satoshis, required), +}); /// When on-chain outputs are created by rust-lightning (which our counterparty is not able to /// claim at any point in the future) an event is generated which you must track and be able to @@ -102,8 +119,8 @@ impl StaticPaymentOutputDescriptor { #[derive(Clone, Debug, PartialEq)] pub enum SpendableOutputDescriptor { /// An output to a script which was provided via KeysInterface directly, either from - /// `get_destination_script()` or `get_shutdown_pubkey()`, thus you should already know how to - /// spend it. No secret keys are provided as rust-lightning was never given any key. + /// `get_destination_script()` or `get_shutdown_scriptpubkey()`, thus you should already know + /// how to spend it. No secret keys are provided as rust-lightning was never given any key. /// These may include outputs from a transaction punishing our counterparty or claiming an HTLC /// on-chain using the payment preimage or after it has timed out. StaticOutput { @@ -151,62 +168,15 @@ pub enum SpendableOutputDescriptor { StaticPaymentOutput(StaticPaymentOutputDescriptor), } -impl Writeable for SpendableOutputDescriptor { - fn write(&self, writer: &mut W) -> Result<(), ::std::io::Error> { - match self { - &SpendableOutputDescriptor::StaticOutput { ref outpoint, ref output } => { - 0u8.write(writer)?; - outpoint.write(writer)?; - output.write(writer)?; - }, - &SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) => { - 1u8.write(writer)?; - descriptor.outpoint.write(writer)?; - descriptor.per_commitment_point.write(writer)?; - descriptor.to_self_delay.write(writer)?; - descriptor.output.write(writer)?; - descriptor.revocation_pubkey.write(writer)?; - descriptor.channel_keys_id.write(writer)?; - descriptor.channel_value_satoshis.write(writer)?; - }, - &SpendableOutputDescriptor::StaticPaymentOutput(ref descriptor) => { - 2u8.write(writer)?; - descriptor.outpoint.write(writer)?; - descriptor.output.write(writer)?; - descriptor.channel_keys_id.write(writer)?; - descriptor.channel_value_satoshis.write(writer)?; - }, - } - Ok(()) - } -} - -impl Readable for SpendableOutputDescriptor { - fn read(reader: &mut R) -> Result { - match Readable::read(reader)? { - 0u8 => Ok(SpendableOutputDescriptor::StaticOutput { - outpoint: Readable::read(reader)?, - output: Readable::read(reader)?, - }), - 1u8 => Ok(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor { - outpoint: Readable::read(reader)?, - per_commitment_point: Readable::read(reader)?, - to_self_delay: Readable::read(reader)?, - output: Readable::read(reader)?, - revocation_pubkey: Readable::read(reader)?, - channel_keys_id: Readable::read(reader)?, - channel_value_satoshis: Readable::read(reader)?, - })), - 2u8 => Ok(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor { - outpoint: Readable::read(reader)?, - output: Readable::read(reader)?, - channel_keys_id: Readable::read(reader)?, - channel_value_satoshis: Readable::read(reader)?, - })), - _ => Err(DecodeError::InvalidValue), - } - } -} +impl_writeable_tlv_based_enum!(SpendableOutputDescriptor, + (0, StaticOutput) => { + (0, outpoint, required), + (2, output, required), + }, +; + (1, DelayedPaymentOutput), + (2, StaticPaymentOutput), +); /// A trait to sign lightning channel transactions as described in BOLT 3. /// @@ -242,6 +212,13 @@ pub trait BaseSign { /// Note that the commitment number starts at (1 << 48) - 1 and counts backwards. // TODO: return a Result so we can signal a validation error fn release_commitment_secret(&self, idx: u64) -> [u8; 32]; + /// Validate the counterparty's signatures on the holder commitment transaction and HTLCs. + /// + /// This is required in order for the signer to make sure that releasing a commitment + /// secret won't leave us without a broadcastable holder transaction. + /// Policy checks should be implemented in this function, including checking the amount + /// sent to us and checking the HTLCs. + fn validate_holder_commitment(&self, holder_tx: &HolderCommitmentTransaction) -> Result<(), ()>; /// Gets the holder's channel public keys and basepoints fn pubkeys(&self) -> &ChannelPublicKeys; /// Gets an arbitrary identifier describing the set of keys which are provided back to you in @@ -252,9 +229,17 @@ pub trait BaseSign { /// Create a signature for a counterparty's commitment transaction and associated HTLC transactions. /// /// Note that if signing fails or is rejected, the channel will be force-closed. + /// + /// Policy checks should be implemented in this function, including checking the amount + /// sent to us and checking the HTLCs. // // TODO: Document the things someone using this interface should enforce before signing. fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + /// Validate the counterparty's revocation. + /// + /// This is required in order for the signer to make sure that the state has moved + /// forward and it is safe to sign the next counterparty commitment. + fn validate_counterparty_revocation(&self, idx: u64, secret: &SecretKey) -> Result<(), ()>; /// Create a signatures for a holder's commitment transaction and its claiming HTLC transactions. /// This will only ever be called with a non-revoked commitment_tx. This will be called with the @@ -337,7 +322,7 @@ pub trait BaseSign { /// /// Note that, due to rounding, there may be one "missing" satoshi, and either party may have /// chosen to forgo their output as dust. - fn sign_closing_transaction(&self, closing_tx: &Transaction, secp_ctx: &Secp256k1) -> Result; + fn sign_closing_transaction(&self, closing_tx: &ClosingTransaction, secp_ctx: &Secp256k1) -> Result; /// Signs a channel announcement message with our funding key, proving it comes from one /// of the channel participants. @@ -382,12 +367,11 @@ pub trait KeysInterface { /// This method should return a different value each time it is called, to avoid linking /// on-chain funds across channels as controlled to the same user. fn get_destination_script(&self) -> Script; - /// Get a public key which we will send funds to (in the form of a P2WPKH output) when closing - /// a channel. + /// Get a script pubkey which we will send funds to when closing a channel. /// /// This method should return a different value each time it is called, to avoid linking /// on-chain funds across channels as controlled to the same user. - fn get_shutdown_pubkey(&self) -> PublicKey; + fn get_shutdown_scriptpubkey(&self) -> ShutdownScript; /// Get a new set of Sign for per-channel secrets. These MUST be unique even if you /// restarted with some stale data! /// @@ -521,6 +505,12 @@ impl InMemorySigner { self.channel_parameters.as_ref().unwrap() } + /// Whether anchors should be used. + /// Will panic if ready_channel wasn't called. + pub fn opt_anchors(&self) -> bool { + self.get_channel_parameters().opt_anchors.is_some() + } + /// Sign the single input of spend_tx at index `input_idx` which spends the output /// described by descriptor, returning the witness stack for the input. /// @@ -589,6 +579,10 @@ impl BaseSign for InMemorySigner { chan_utils::build_commitment_secret(&self.commitment_seed, idx) } + fn validate_holder_commitment(&self, _holder_tx: &HolderCommitmentTransaction) -> Result<(), ()> { + Ok(()) + } + fn pubkeys(&self) -> &ChannelPublicKeys { &self.holder_channel_pubkeys } fn channel_keys_id(&self) -> [u8; 32] { self.channel_keys_id } @@ -605,8 +599,8 @@ impl BaseSign for InMemorySigner { let mut htlc_sigs = Vec::with_capacity(commitment_tx.htlcs().len()); for htlc in commitment_tx.htlcs() { - let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_tx.feerate_per_kw(), self.holder_selected_contest_delay(), htlc, &keys.broadcaster_delayed_payment_key, &keys.revocation_key); - let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys); + let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_tx.feerate_per_kw(), self.holder_selected_contest_delay(), htlc, self.opt_anchors(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key); + let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, self.opt_anchors(), &keys); let htlc_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]); let holder_htlc_key = chan_utils::derive_private_key(&secp_ctx, &keys.per_commitment_point, &self.htlc_base_key).map_err(|_| ())?; htlc_sigs.push(secp_ctx.sign(&htlc_sighash, &holder_htlc_key)); @@ -615,6 +609,10 @@ impl BaseSign for InMemorySigner { Ok((commitment_sig, htlc_sigs)) } + fn validate_counterparty_revocation(&self, _idx: u64, _secret: &SecretKey) -> Result<(), ()> { + Ok(()) + } + fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); let funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &self.counterparty_pubkeys().funding_pubkey); @@ -656,7 +654,7 @@ impl BaseSign for InMemorySigner { let witness_script = { let counterparty_htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().htlc_basepoint).map_err(|_| ())?; let holder_htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.pubkeys().htlc_basepoint).map_err(|_| ())?; - chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &counterparty_htlcpubkey, &holder_htlcpubkey, &revocation_pubkey) + chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, self.opt_anchors(), &counterparty_htlcpubkey, &holder_htlcpubkey, &revocation_pubkey) }; let mut sighash_parts = bip143::SigHashCache::new(justice_tx); let sighash = hash_to_message!(&sighash_parts.signature_hash(input, &witness_script, amount, SigHashType::All)[..]); @@ -668,7 +666,7 @@ impl BaseSign for InMemorySigner { let witness_script = if let Ok(revocation_pubkey) = chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &self.pubkeys().revocation_basepoint) { if let Ok(counterparty_htlcpubkey) = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().htlc_basepoint) { if let Ok(htlcpubkey) = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.pubkeys().htlc_basepoint) { - chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &counterparty_htlcpubkey, &htlcpubkey, &revocation_pubkey) + chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, self.opt_anchors(), &counterparty_htlcpubkey, &htlcpubkey, &revocation_pubkey) } else { return Err(()) } } else { return Err(()) } } else { return Err(()) }; @@ -679,17 +677,10 @@ impl BaseSign for InMemorySigner { Err(()) } - fn sign_closing_transaction(&self, closing_tx: &Transaction, secp_ctx: &Secp256k1) -> Result { - if closing_tx.input.len() != 1 { return Err(()); } - if closing_tx.input[0].witness.len() != 0 { return Err(()); } - if closing_tx.output.len() > 2 { return Err(()); } - + fn sign_closing_transaction(&self, closing_tx: &ClosingTransaction, secp_ctx: &Secp256k1) -> Result { let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &self.counterparty_pubkeys().funding_pubkey); - - let sighash = hash_to_message!(&bip143::SigHashCache::new(closing_tx) - .signature_hash(0, &channel_funding_redeemscript, self.channel_value_satoshis, SigHashType::All)[..]); - Ok(secp_ctx.sign(&sighash, &self.funding_key)) + Ok(closing_tx.trust().sign(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx)) } fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result { @@ -704,10 +695,15 @@ impl BaseSign for InMemorySigner { } } +const SERIALIZATION_VERSION: u8 = 1; +const MIN_SERIALIZATION_VERSION: u8 = 1; + impl Sign for InMemorySigner {} impl Writeable for InMemorySigner { fn write(&self, writer: &mut W) -> Result<(), Error> { + write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION); + self.funding_key.write(writer)?; self.revocation_base_key.write(writer)?; self.payment_key.write(writer)?; @@ -718,12 +714,16 @@ impl Writeable for InMemorySigner { self.channel_value_satoshis.write(writer)?; self.channel_keys_id.write(writer)?; + write_tlv_fields!(writer, {}); + Ok(()) } } impl Readable for InMemorySigner { - fn read(reader: &mut R) -> Result { + fn read(reader: &mut R) -> Result { + let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION); + let funding_key = Readable::read(reader)?; let revocation_base_key = Readable::read(reader)?; let payment_key = Readable::read(reader)?; @@ -739,6 +739,8 @@ impl Readable for InMemorySigner { &htlc_base_key); let keys_id = Readable::read(reader)?; + read_tlv_fields!(reader, {}); + Ok(InMemorySigner { funding_key, revocation_base_key, @@ -857,7 +859,7 @@ impl KeysManager { /// onchain output detection for which a corresponding delayed_payment_key must be derived. pub fn derive_channel_keys(&self, channel_value_satoshis: u64, params: &[u8; 32]) -> InMemorySigner { let chan_id = byte_utils::slice_to_be64(¶ms[0..8]); - assert!(chan_id <= std::u32::MAX as u64); // Otherwise the params field wasn't created by us + assert!(chan_id <= core::u32::MAX as u64); // Otherwise the params field wasn't created by us let mut unique_start = Sha256::engine(); unique_start.input(params); unique_start.input(&self.seed); @@ -964,7 +966,8 @@ impl KeysManager { input, output: outputs, }; - transaction_utils::maybe_add_change_output(&mut spend_tx, input_value, witness_weight, feerate_sat_per_1000_weight, change_destination_script)?; + let expected_max_weight = + transaction_utils::maybe_add_change_output(&mut spend_tx, input_value, witness_weight, feerate_sat_per_1000_weight, change_destination_script)?; let mut keys_cache: Option<(InMemorySigner, [u8; 32])> = None; let mut input_idx = 0; @@ -1018,6 +1021,12 @@ impl KeysManager { } input_idx += 1; } + + debug_assert!(expected_max_weight >= spend_tx.get_weight()); + // Note that witnesses with a signature vary somewhat in size, so allow + // `expected_max_weight` to overshoot by up to 3 bytes per input. + debug_assert!(expected_max_weight <= spend_tx.get_weight() + descriptors.len() * 3); + Ok(spend_tx) } } @@ -1033,13 +1042,13 @@ impl KeysInterface for KeysManager { self.destination_script.clone() } - fn get_shutdown_pubkey(&self) -> PublicKey { - self.shutdown_pubkey.clone() + fn get_shutdown_scriptpubkey(&self) -> ShutdownScript { + ShutdownScript::new_p2wpkh_from_pubkey(self.shutdown_pubkey.clone()) } fn get_channel_signer(&self, _inbound: bool, channel_value_satoshis: u64) -> Self::Signer { let child_ix = self.channel_child_index.fetch_add(1, Ordering::AcqRel); - assert!(child_ix <= std::u32::MAX as usize); + assert!(child_ix <= core::u32::MAX as usize); let mut id = [0; 32]; id[0..8].copy_from_slice(&byte_utils::be64_to_array(child_ix as u64)); id[8..16].copy_from_slice(&byte_utils::be64_to_array(self.starting_time_nanos as u64)); @@ -1059,7 +1068,7 @@ impl KeysInterface for KeysManager { } fn read_chan_signer(&self, reader: &[u8]) -> Result { - InMemorySigner::read(&mut std::io::Cursor::new(reader)) + InMemorySigner::read(&mut io::Cursor::new(reader)) } fn sign_invoice(&self, invoice_preimage: Vec) -> Result {