X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fkeysinterface.rs;h=0a4366e881fa743af704a8b70c2d5cc23c1f7a05;hb=4395b92cc8bfe0cc803e70bba11f4db58d5d0dbf;hp=449327791649f600d78fb155243bc5bf578bffc3;hpb=42b731d92b29265d57e976691e1233e2bc6b3a1b;p=rust-lightning diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index 44932779..0a4366e8 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -1,3 +1,12 @@ +// This file is Copyright its original authors, visible in version control +// history. +// +// This file is licensed under the Apache License, Version 2.0 or the MIT license +// , at your option. +// You may not use this file except in accordance with one or both of these +// licenses. + //! keysinterface provides keys into rust-lightning and defines some useful enums which describe //! spendable on-chain outputs which the user owns and is responsible for using just as any other //! on-chain output which is theirs. @@ -23,7 +32,7 @@ use util::byte_utils; use util::ser::{Writeable, Writer, Readable}; use ln::chan_utils; -use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, LocalCommitmentTransaction}; +use ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, LocalCommitmentTransaction, PreCalculatedTxCreationKeys}; use ln::msgs; use std::sync::atomic::{AtomicUsize, Ordering}; @@ -54,26 +63,30 @@ pub enum SpendableOutputDescriptor { /// (MINIMALIF standard rule) /// /// Note that the nSequence field in the spending input must be set to to_self_delay - /// (which means the transaction not being broadcastable until at least to_self_delay + /// (which means the transaction is not broadcastable until at least to_self_delay /// blocks after the outpoint confirms). /// /// These are generally the result of a "revocable" output to us, spendable only by us unless - /// it is an output from us having broadcast an old state (which should never happen). - /// - /// WitnessScript may be regenerated by passing the revocation_pubkey, to_self_delay and - /// delayed_payment_pubkey to chan_utils::get_revokeable_redeemscript. + /// it is an output from an old state which we broadcast (which should never happen). /// - /// To derive the delayed_payment key corresponding to the channel state, you must pass the - /// local delayed_payment_base_key and the provided per_commitment_point to - /// chan_utils::derive_private_key. The resulting key should be used to sign the spending - /// transaction. + /// To derive the delayed_payment key which is used to sign for this input, you must pass the + /// local delayed_payment_base_key (ie the private key which corresponds to the pubkey in + /// ChannelKeys::pubkeys().delayed_payment_basepoint) and the provided per_commitment_point to + /// chan_utils::derive_private_key. The public key can be generated without the secret key + /// using chan_utils::derive_public_key and only the delayed_payment_basepoint which appears in + /// ChannelKeys::pubkeys(). /// - /// To derive the revocation_pubkey corresponding to the channel state, you must pass the - /// remote revocation_basepoint and the provided per_commitment point to - /// chan_utils::derive_public_revocation_key. + /// To derive the remote_revocation_pubkey provided here (which is used in the witness + /// script generation), you must pass the remote revocation_basepoint (which appears in the + /// call to ChannelKeys::on_accept) and the provided per_commitment point + /// to chan_utils::derive_public_revocation_key. /// - /// Both remote revocation_basepoint and local delayed_payment_base_key should be given - /// by ChannelKeys, either default implementation (InMemoryChannelKeys) or custom one. + /// The witness script which is hashed and included in the output script_pubkey may be + /// regenerated by passing the revocation_pubkey (derived as above), our delayed_payment pubkey + /// (derived as above), and the to_self_delay contained here to + /// chan_utils::get_revokeable_redeemscript. + // + // TODO: we need to expose utility methods in KeyManager to do all the relevant derivation. DynamicOutputP2WSH { /// The outpoint which is spendable outpoint: OutPoint, @@ -90,7 +103,8 @@ pub enum SpendableOutputDescriptor { /// The remote_revocation_pubkey used to derive witnessScript remote_revocation_pubkey: PublicKey }, - /// An output to a P2WPKH, spendable exclusively by our payment key. + /// An output to a P2WPKH, spendable exclusively by our payment key (ie the private key which + /// corresponds to the public key in ChannelKeys::pubkeys().payment_point). /// The witness in the spending input, is, thus, simply: /// /// @@ -162,28 +176,6 @@ impl Readable for SpendableOutputDescriptor { } } -/// A trait to describe an object which can get user secrets and key material. -pub trait KeysInterface: Send + Sync { - /// A type which implements ChannelKeys which will be returned by get_channel_keys. - type ChanKeySigner : ChannelKeys; - - /// Get node secret key (aka node_id or network_key) - fn get_node_secret(&self) -> SecretKey; - /// Get destination redeemScript to encumber static protocol exit points. - fn get_destination_script(&self) -> Script; - /// Get shutdown_pubkey to use as PublicKey at channel closure - fn get_shutdown_pubkey(&self) -> PublicKey; - /// Get a new set of ChannelKeys for per-channel secrets. These MUST be unique even if you - /// restarted with some stale data! - fn get_channel_keys(&self, inbound: bool, channel_value_satoshis: u64) -> Self::ChanKeySigner; - /// Get a secret and PRNG seed for construting an onion packet - fn get_onion_rand(&self) -> (SecretKey, [u8; 32]); - /// Get a unique temporary channel id. Channels will be referred to by this until the funding - /// transaction is created, at which point they will use the outpoint in the funding - /// transaction. - fn get_channel_id(&self) -> [u8; 32]; -} - /// Set of lightning keys needed to operate a channel as described in BOLT 3. /// /// Signing services could be implemented on a hardware wallet. In this case, @@ -212,22 +204,22 @@ pub trait KeysInterface: Send + Sync { // TODO: We should remove Clone by instead requesting a new ChannelKeys copy when we create // ChannelMonitors instead of expecting to clone the one out of the Channel into the monitors. pub trait ChannelKeys : Send+Clone { - /// Gets the private key for the anchor tx - fn funding_key<'a>(&'a self) -> &'a SecretKey; - /// Gets the local secret key for blinded revocation pubkey - fn revocation_base_key<'a>(&'a self) -> &'a SecretKey; - /// Gets the local secret key used in the to_remote output of remote commitment tx (ie the - /// output to us in transactions our counterparty broadcasts). - /// Also as part of obscured commitment number. - fn payment_key<'a>(&'a self) -> &'a SecretKey; - /// Gets the local secret key used in HTLC-Success/HTLC-Timeout txn and to_local output - fn delayed_payment_base_key<'a>(&'a self) -> &'a SecretKey; - /// Gets the local htlc secret key used in commitment tx htlc outputs - fn htlc_base_key<'a>(&'a self) -> &'a SecretKey; - /// Gets the commitment seed - fn commitment_seed<'a>(&'a self) -> &'a [u8; 32]; + /// Gets the per-commitment point for a specific commitment number + /// + /// Note that the commitment number starts at (1 << 48) - 1 and counts backwards. + fn get_per_commitment_point(&self, idx: u64, secp_ctx: &Secp256k1) -> PublicKey; + /// Gets the commitment secret for a specific commitment number as part of the revocation process + /// + /// An external signer implementation should error here if the commitment was already signed + /// and should refuse to sign it in the future. + /// + /// May be called more than once for the same index. + /// + /// 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]; /// Gets the local channel public keys and basepoints - fn pubkeys<'a>(&'a self) -> &'a ChannelPublicKeys; + fn pubkeys(&self) -> &ChannelPublicKeys; /// Gets arbitrary identifiers describing the set of keys which are provided back to you in /// some SpendableOutputDescriptor types. These should be sufficient to identify this /// ChannelKeys object uniquely and lookup or re-derive its keys. @@ -240,11 +232,12 @@ pub trait ChannelKeys : Send+Clone { // TODO: Document the things someone using this interface should enforce before signing. // TODO: Add more input vars to enable better checking (preferably removing commitment_tx and // making the callee generate it via some util function we expose)! - fn sign_remote_commitment(&self, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + fn sign_remote_commitment(&self, feerate_per_kw: u32, commitment_tx: &Transaction, keys: &PreCalculatedTxCreationKeys, htlcs: &[&HTLCOutputInCommitment], secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; /// Create a signature for a local commitment transaction. This will only ever be called with /// the same local_commitment_tx (or a copy thereof), though there are currently no guarantees /// that it will not be called multiple times. + /// An external signer implementation should check that the commitment has not been revoked. // // TODO: Document the things someone using this interface should enforce before signing. // TODO: Add more input vars to enable better checking (preferably removing commitment_tx and @@ -270,49 +263,45 @@ pub trait ChannelKeys : Send+Clone { /// (implying they were considered dust at the time the commitment transaction was negotiated), /// a corresponding None should be included in the return value. All other positions in the /// return value must contain a signature. - fn sign_local_commitment_htlc_transactions(&self, local_commitment_tx: &LocalCommitmentTransaction, local_csv: u16, secp_ctx: &Secp256k1) -> Result>, ()>; + fn sign_local_commitment_htlc_transactions(&self, local_commitment_tx: &LocalCommitmentTransaction, secp_ctx: &Secp256k1) -> Result>, ()>; - /// Create a signature for a transaction spending an HTLC or commitment transaction output - /// when our counterparty broadcast an old state. + /// Create a signature for the given input in a transaction spending an HTLC or commitment + /// transaction output when our counterparty broadcasts an old state. /// - /// Justice transaction may claim multiples outputs at same time if timelock are similar. + /// A justice transaction may claim multiples outputs at the same time if timelocks are + /// similar, but only a signature for the input at index `input` should be signed for here. /// It may be called multiples time for same output(s) if a fee-bump is needed with regards /// to an upcoming timelock expiration. /// - /// Input index is a pointer towards outpoint spent, commited by sigs (BIP 143). - /// - /// Amount is value of the output spent by this input, committed by sigs (BIP 143). + /// Amount is value of the output spent by this input, committed to in the BIP 143 signature. /// - /// Per_commitment key is revocation secret such as provided by remote party while - /// revocating detected onchain transaction. It's not a _local_ secret key, therefore - /// it may cross interfaces, a node compromise won't allow to spend revoked output without - /// also compromissing revocation key. + /// per_commitment_key is revocation secret which was provided by our counterparty when they + /// revoked the state which they eventually broadcast. It's not a _local_ secret key and does + /// not allow the spending of any funds by itself (you need our local revocation_secret to do + /// so). /// - /// htlc holds HTLC elements (hash, timelock) if output spent is a HTLC one, committed as - /// part of witnessScript by sigs (BIP 143). - /// - /// on_remote_tx_csv is the relative lock-time challenge if output spent is on remote - /// balance or 2nd-stage HTLC transactions, committed as part of witnessScript by sigs - /// (BIP 143). - fn sign_justice_transaction(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &Option, on_remote_tx_csv: u16, secp_ctx: &Secp256k1) -> Result; + /// htlc holds HTLC elements (hash, timelock) if the output being spent is a HTLC output, thus + /// changing the format of the witness script (which is committed to in the BIP 143 + /// signatures). + fn sign_justice_transaction(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &Option, secp_ctx: &Secp256k1) -> Result; /// Create a signature for a claiming transaction for a HTLC output on a remote commitment /// transaction, either offered or received. /// - /// HTLC transaction may claim multiples offered outputs at same time if we know preimage - /// for each at detection. It may be called multtiples time for same output(s) if a fee-bump - /// is needed with regards to an upcoming timelock expiration. + /// Such a transaction may claim multiples offered outputs at same time if we know the + /// preimage for each when we create it, but only the input at index `input` should be + /// signed for here. It may be called multiple times for same output(s) if a fee-bump is + /// needed with regards to an upcoming timelock expiration. /// /// Witness_script is either a offered or received script as defined in BOLT3 for HTLC /// outputs. /// - /// Input index is a pointer towards outpoint spent, commited by sigs (BIP 143). - /// - /// Amount is value of the output spent by this input, committed by sigs (BIP 143). + /// Amount is value of the output spent by this input, committed to in the BIP 143 signature. /// /// Per_commitment_point is the dynamic point corresponding to the channel state - /// detected onchain. It has been generated by remote party and is used to derive - /// channel state keys, committed as part of witnessScript by sigs (BIP 143). + /// detected onchain. It has been generated by our counterparty and is used to derive + /// channel state keys, which are then included in the witness script and committed to in the + /// BIP 143 signature. fn sign_remote_htlc_transaction(&self, htlc_tx: &Transaction, input: usize, amount: u64, per_commitment_point: &PublicKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result; /// Create a signature for a (proposed) closing transaction. @@ -329,32 +318,75 @@ pub trait ChannelKeys : Send+Clone { /// protocol. fn sign_channel_announcement(&self, msg: &msgs::UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result; - /// Set the remote channel basepoints. This is done immediately on incoming channels - /// and as soon as the channel is accepted on outgoing channels. + /// Set the remote channel basepoints and remote/local to_self_delay. + /// This is done immediately on incoming channels and as soon as the channel is accepted on outgoing channels. + /// + /// We bind local_to_self_delay late here for API convenience. /// /// Will be called before any signatures are applied. - fn set_remote_channel_pubkeys(&mut self, channel_points: &ChannelPublicKeys); + fn on_accept(&mut self, channel_points: &ChannelPublicKeys, remote_to_self_delay: u16, local_to_self_delay: u16); +} + +/// A trait to describe an object which can get user secrets and key material. +pub trait KeysInterface: Send + Sync { + /// A type which implements ChannelKeys which will be returned by get_channel_keys. + type ChanKeySigner : ChannelKeys; + + /// Get node secret key (aka node_id or network_key) + fn get_node_secret(&self) -> SecretKey; + /// Get destination redeemScript to encumber static protocol exit points. + fn get_destination_script(&self) -> Script; + /// Get shutdown_pubkey to use as PublicKey at channel closure + fn get_shutdown_pubkey(&self) -> PublicKey; + /// Get a new set of ChannelKeys for per-channel secrets. These MUST be unique even if you + /// restarted with some stale data! + fn get_channel_keys(&self, inbound: bool, channel_value_satoshis: u64) -> Self::ChanKeySigner; + /// Get a secret and PRNG seed for constructing an onion packet + fn get_onion_rand(&self) -> (SecretKey, [u8; 32]); + /// Get a unique temporary channel id. Channels will be referred to by this until the funding + /// transaction is created, at which point they will use the outpoint in the funding + /// transaction. + fn get_channel_id(&self) -> [u8; 32]; +} + +#[derive(Clone)] +/// Holds late-bound channel data. +/// This data is available after the channel is known to be accepted, either +/// when receiving an open_channel for an inbound channel or when +/// receiving accept_channel for an outbound channel. +struct AcceptedChannelData { + /// Remote public keys and base points + remote_channel_pubkeys: ChannelPublicKeys, + /// The to_self_delay value specified by our counterparty and applied on locally-broadcastable + /// transactions, ie the amount of time that we have to wait to recover our funds if we + /// broadcast a transaction. You'll likely want to pass this to the + /// ln::chan_utils::build*_transaction functions when signing local transactions. + remote_to_self_delay: u16, + /// The to_self_delay value specified by us and applied on transactions broadcastable + /// by our counterparty, ie the amount of time that they have to wait to recover their funds + /// if they broadcast a transaction. + local_to_self_delay: u16, } #[derive(Clone)] /// A simple implementation of ChannelKeys that just keeps the private keys in memory. pub struct InMemoryChannelKeys { /// Private key of anchor tx - funding_key: SecretKey, + pub funding_key: SecretKey, /// Local secret key for blinded revocation pubkey - revocation_base_key: SecretKey, + pub revocation_base_key: SecretKey, /// Local secret key used for our balance in remote-broadcasted commitment transactions - payment_key: SecretKey, + pub payment_key: SecretKey, /// Local secret key used in HTLC tx - delayed_payment_base_key: SecretKey, + pub delayed_payment_base_key: SecretKey, /// Local htlc secret key used in commitment tx htlc outputs - htlc_base_key: SecretKey, + pub htlc_base_key: SecretKey, /// Commitment seed - commitment_seed: [u8; 32], + pub commitment_seed: [u8; 32], /// Local public keys and basepoints pub(crate) local_channel_pubkeys: ChannelPublicKeys, - /// Remote public keys and base points - pub(crate) remote_channel_pubkeys: Option, + /// Remote public keys and remote/local to_self_delay, populated on channel acceptance + accepted_channel_data: Option, /// The total value of this channel channel_value_satoshis: u64, /// Key derivation parameters @@ -386,7 +418,7 @@ impl InMemoryChannelKeys { commitment_seed, channel_value_satoshis, local_channel_pubkeys, - remote_channel_pubkeys: None, + accepted_channel_data: None, key_derivation_params, } } @@ -407,25 +439,44 @@ impl InMemoryChannelKeys { } } - fn remote_pubkeys<'a>(&'a self) -> &'a ChannelPublicKeys { self.remote_channel_pubkeys.as_ref().unwrap() } + /// Remote pubkeys. + /// Will panic if on_accept wasn't called. + pub fn remote_pubkeys(&self) -> &ChannelPublicKeys { &self.accepted_channel_data.as_ref().unwrap().remote_channel_pubkeys } + + /// The to_self_delay value specified by our counterparty and applied on locally-broadcastable + /// transactions, ie the amount of time that we have to wait to recover our funds if we + /// broadcast a transaction. You'll likely want to pass this to the + /// ln::chan_utils::build*_transaction functions when signing local transactions. + /// Will panic if on_accept wasn't called. + pub fn remote_to_self_delay(&self) -> u16 { self.accepted_channel_data.as_ref().unwrap().remote_to_self_delay } + + /// The to_self_delay value specified by us and applied on transactions broadcastable + /// by our counterparty, ie the amount of time that they have to wait to recover their funds + /// if they broadcast a transaction. + /// Will panic if on_accept wasn't called. + pub fn local_to_self_delay(&self) -> u16 { self.accepted_channel_data.as_ref().unwrap().local_to_self_delay } } impl ChannelKeys for InMemoryChannelKeys { - fn funding_key(&self) -> &SecretKey { &self.funding_key } - fn revocation_base_key(&self) -> &SecretKey { &self.revocation_base_key } - fn payment_key(&self) -> &SecretKey { &self.payment_key } - fn delayed_payment_base_key(&self) -> &SecretKey { &self.delayed_payment_base_key } - fn htlc_base_key(&self) -> &SecretKey { &self.htlc_base_key } - fn commitment_seed(&self) -> &[u8; 32] { &self.commitment_seed } - fn pubkeys<'a>(&'a self) -> &'a ChannelPublicKeys { &self.local_channel_pubkeys } + fn get_per_commitment_point(&self, idx: u64, secp_ctx: &Secp256k1) -> PublicKey { + let commitment_secret = SecretKey::from_slice(&chan_utils::build_commitment_secret(&self.commitment_seed, idx)).unwrap(); + PublicKey::from_secret_key(secp_ctx, &commitment_secret) + } + + fn release_commitment_secret(&self, idx: u64) -> [u8; 32] { + chan_utils::build_commitment_secret(&self.commitment_seed, idx) + } + + fn pubkeys(&self) -> &ChannelPublicKeys { &self.local_channel_pubkeys } fn key_derivation_params(&self) -> (u64, u64) { self.key_derivation_params } - fn sign_remote_commitment(&self, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { + fn sign_remote_commitment(&self, feerate_per_kw: u32, commitment_tx: &Transaction, pre_keys: &PreCalculatedTxCreationKeys, htlcs: &[&HTLCOutputInCommitment], secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { if commitment_tx.input.len() != 1 { return Err(()); } + let keys = pre_keys.trust_key_derivation(); let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); - let remote_channel_pubkeys = self.remote_channel_pubkeys.as_ref().expect("must set remote channel pubkeys before signing"); - let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_pubkeys.funding_pubkey); + let accepted_data = self.accepted_channel_data.as_ref().expect("must accept before signing"); + let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &accepted_data.remote_channel_pubkeys.funding_pubkey); let commitment_sighash = hash_to_message!(&bip143::SighashComponents::new(&commitment_tx).sighash_all(&commitment_tx.input[0], &channel_funding_redeemscript, self.channel_value_satoshis)[..]); let commitment_sig = secp_ctx.sign(&commitment_sighash, &self.funding_key); @@ -435,7 +486,7 @@ impl ChannelKeys for InMemoryChannelKeys { let mut htlc_sigs = Vec::with_capacity(htlcs.len()); for ref htlc in htlcs { if let Some(_) = htlc.transaction_output_index { - let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw, to_self_delay, htlc, &keys.a_delayed_payment_key, &keys.revocation_key); + let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, feerate_per_kw, accepted_data.local_to_self_delay, htlc, &keys.a_delayed_payment_key, &keys.revocation_key); let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys); let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]); let our_htlc_key = match chan_utils::derive_private_key(&secp_ctx, &keys.per_commitment_point, &self.htlc_base_key) { @@ -451,8 +502,8 @@ impl ChannelKeys for InMemoryChannelKeys { fn sign_local_commitment(&self, local_commitment_tx: &LocalCommitmentTransaction, secp_ctx: &Secp256k1) -> Result { let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); - let remote_channel_pubkeys = self.remote_channel_pubkeys.as_ref().expect("must set remote channel pubkeys before signing"); - let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_pubkeys.funding_pubkey); + let remote_channel_data = self.accepted_channel_data.as_ref().expect("must accept before signing"); + let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_data.remote_channel_pubkeys.funding_pubkey); Ok(local_commitment_tx.get_local_sig(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx)) } @@ -460,17 +511,18 @@ impl ChannelKeys for InMemoryChannelKeys { #[cfg(test)] fn unsafe_sign_local_commitment(&self, local_commitment_tx: &LocalCommitmentTransaction, secp_ctx: &Secp256k1) -> Result { let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); - let remote_channel_pubkeys = self.remote_channel_pubkeys.as_ref().expect("must set remote channel pubkeys before signing"); + let remote_channel_pubkeys = &self.accepted_channel_data.as_ref().expect("must accept before signing").remote_channel_pubkeys; let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_pubkeys.funding_pubkey); Ok(local_commitment_tx.get_local_sig(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx)) } - fn sign_local_commitment_htlc_transactions(&self, local_commitment_tx: &LocalCommitmentTransaction, local_csv: u16, secp_ctx: &Secp256k1) -> Result>, ()> { + fn sign_local_commitment_htlc_transactions(&self, local_commitment_tx: &LocalCommitmentTransaction, secp_ctx: &Secp256k1) -> Result>, ()> { + let local_csv = self.accepted_channel_data.as_ref().unwrap().remote_to_self_delay; local_commitment_tx.get_htlc_sigs(&self.htlc_base_key, local_csv, secp_ctx) } - fn sign_justice_transaction(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &Option, on_remote_tx_csv: u16, secp_ctx: &Secp256k1) -> Result { + fn sign_justice_transaction(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &Option, secp_ctx: &Secp256k1) -> Result { let revocation_key = match chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_key, &self.revocation_base_key) { Ok(revocation_key) => revocation_key, Err(_) => return Err(()) @@ -495,7 +547,7 @@ impl ChannelKeys for InMemoryChannelKeys { Ok(remote_delayedpubkey) => remote_delayedpubkey, Err(_) => return Err(()) }; - chan_utils::get_revokeable_redeemscript(&revocation_pubkey, on_remote_tx_csv, &remote_delayedpubkey) + chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.local_to_self_delay(), &remote_delayedpubkey) }; let sighash_parts = bip143::SighashComponents::new(&justice_tx); let sighash = hash_to_message!(&sighash_parts.sighash_all(&justice_tx.input[input], &witness_script, amount)[..]); @@ -523,9 +575,9 @@ impl ChannelKeys for InMemoryChannelKeys { if closing_tx.input[0].witness.len() != 0 { return Err(()); } if closing_tx.output.len() > 2 { return Err(()); } - let remote_channel_pubkeys = self.remote_channel_pubkeys.as_ref().expect("must set remote channel pubkeys before signing"); let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); - let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_pubkeys.funding_pubkey); + let remote_channel_data = self.accepted_channel_data.as_ref().expect("must accept before signing"); + let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &remote_channel_data.remote_channel_pubkeys.funding_pubkey); let sighash = hash_to_message!(&bip143::SighashComponents::new(closing_tx) .sighash_all(&closing_tx.input[0], &channel_funding_redeemscript, self.channel_value_satoshis)[..]); @@ -537,12 +589,19 @@ impl ChannelKeys for InMemoryChannelKeys { Ok(secp_ctx.sign(&msghash, &self.funding_key)) } - fn set_remote_channel_pubkeys(&mut self, channel_pubkeys: &ChannelPublicKeys) { - assert!(self.remote_channel_pubkeys.is_none(), "Already set remote channel pubkeys"); - self.remote_channel_pubkeys = Some(channel_pubkeys.clone()); + fn on_accept(&mut self, channel_pubkeys: &ChannelPublicKeys, remote_to_self_delay: u16, local_to_self_delay: u16) { + assert!(self.accepted_channel_data.is_none(), "Already accepted"); + self.accepted_channel_data = Some(AcceptedChannelData { + remote_channel_pubkeys: channel_pubkeys.clone(), + remote_to_self_delay, + local_to_self_delay, + }); } } +impl_writeable!(AcceptedChannelData, 0, + { remote_channel_pubkeys, remote_to_self_delay, local_to_self_delay }); + impl Writeable for InMemoryChannelKeys { fn write(&self, writer: &mut W) -> Result<(), Error> { self.funding_key.write(writer)?; @@ -551,7 +610,7 @@ impl Writeable for InMemoryChannelKeys { self.delayed_payment_base_key.write(writer)?; self.htlc_base_key.write(writer)?; self.commitment_seed.write(writer)?; - self.remote_channel_pubkeys.write(writer)?; + self.accepted_channel_data.write(writer)?; self.channel_value_satoshis.write(writer)?; self.key_derivation_params.0.write(writer)?; self.key_derivation_params.1.write(writer)?; @@ -568,7 +627,7 @@ impl Readable for InMemoryChannelKeys { let delayed_payment_base_key = Readable::read(reader)?; let htlc_base_key = Readable::read(reader)?; let commitment_seed = Readable::read(reader)?; - let remote_channel_pubkeys = Readable::read(reader)?; + let remote_channel_data = Readable::read(reader)?; let channel_value_satoshis = Readable::read(reader)?; let secp_ctx = Secp256k1::signing_only(); let local_channel_pubkeys = @@ -587,7 +646,7 @@ impl Readable for InMemoryChannelKeys { commitment_seed, channel_value_satoshis, local_channel_pubkeys, - remote_channel_pubkeys, + accepted_channel_data: remote_channel_data, key_derivation_params: (params_1, params_2), }) } @@ -637,7 +696,7 @@ impl KeysManager { /// Note that until the 0.1 release there is no guarantee of backward compatibility between /// versions. Once the library is more fully supported, the docs will be updated to include a /// detailed description of the guarantee. - pub fn new(seed: &[u8; 32], network: Network, starting_time_secs: u64, starting_time_nanos: u32) -> KeysManager { + pub fn new(seed: &[u8; 32], network: Network, starting_time_secs: u64, starting_time_nanos: u32) -> Self { let secp_ctx = Secp256k1::signing_only(); match ExtendedPrivKey::new_master(network.clone(), seed) { Ok(master_key) => {