X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fkeysinterface.rs;h=7356dad8e40d64c353a80efa77b89e01c2fed7b8;hb=0dfcacd22c23f69b6526c9c6507d21427a2b7ccb;hp=b3e33b57ca8e0ff3282c85f075f12c6bbc81f080;hpb=414e62230e8bcca5c841222b21a00fe60609ee03;p=rust-lightning diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index b3e33b57..7356dad8 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -26,6 +26,7 @@ use bitcoin::hash_types::WPubkeyHash; use bitcoin::secp256k1::key::{SecretKey, PublicKey}; use bitcoin::secp256k1::{Secp256k1, Signature, Signing}; +use bitcoin::secp256k1::recovery::RecoverableSignature; use bitcoin::secp256k1; use util::{byte_utils, transaction_utils}; @@ -36,9 +37,9 @@ use ln::chan_utils; use ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, HolderCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction}; use ln::msgs::UnsignedChannelAnnouncement; -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 @@ -58,7 +59,7 @@ pub struct DelayedPaymentOutputDescriptor { /// derive the witnessScript for this output. pub revocation_pubkey: PublicKey, /// Arbitrary identification information returned by a call to - /// `ChannelKeys::channel_keys_id()`. This may be useful in re-deriving keys used in + /// `Sign::channel_keys_id()`. This may be useful in re-deriving keys used in /// the channel to spend the output. pub channel_keys_id: [u8; 32], /// The value of the channel which this output originated from, possibly indirectly. @@ -71,6 +72,16 @@ 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)] @@ -80,7 +91,7 @@ pub struct StaticPaymentOutputDescriptor { /// The output which is referenced by the given outpoint pub output: TxOut, /// Arbitrary identification information returned by a call to - /// `ChannelKeys::channel_keys_id()`. This may be useful in re-deriving keys used in + /// `Sign::channel_keys_id()`. This may be useful in re-deriving keys used in /// the channel to spend the output. pub channel_keys_id: [u8; 32], /// The value of the channel which this transactions spends. @@ -92,6 +103,12 @@ 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 @@ -125,14 +142,14 @@ pub enum SpendableOutputDescriptor { /// /// To derive the delayed_payment key which is used to sign for this input, you must pass the /// holder 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 + /// Sign::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(). + /// Sign::pubkeys(). /// /// To derive the revocation_pubkey provided here (which is used in the witness /// script generation), you must pass the counterparty revocation_basepoint (which appears in the - /// call to ChannelKeys::ready_channel) and the provided per_commitment point + /// call to Sign::ready_channel) and the provided per_commitment point /// to chan_utils::derive_public_revocation_key. /// /// The witness script which is hashed and included in the output script_pubkey may be @@ -141,7 +158,7 @@ pub enum SpendableOutputDescriptor { /// chan_utils::get_revokeable_redeemscript. DelayedPaymentOutput(DelayedPaymentOutputDescriptor), /// 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). + /// corresponds to the public key in Sign::pubkeys().payment_point). /// The witness in the spending input, is, thus, simply: /// /// @@ -150,67 +167,20 @@ 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), +); -/// Set of lightning keys needed to operate a channel as described in BOLT 3. +/// A trait to sign lightning channel transactions as described in BOLT 3. /// /// Signing services could be implemented on a hardware wallet. In this case, -/// the current ChannelKeys would be a front-end on top of a communication +/// the current Sign would be a front-end on top of a communication /// channel connected to your secure device and lightning key material wouldn't /// reside on a hot server. Nevertheless, a this deployment would still need /// to trust the ChannelManager to avoid loss of funds as this latest component @@ -224,13 +194,13 @@ impl Readable for SpendableOutputDescriptor { /// In any case, ChannelMonitor or fallback watchtowers are always going to be trusted /// to act, as liveness and breach reply correctness are always going to be hard requirements /// of LN security model, orthogonal of key management issues. -// TODO: We should remove Clone by instead requesting a new ChannelKeys copy when we create +// TODO: We should remove Clone by instead requesting a new Sign copy when we create // ChannelMonitors instead of expecting to clone the one out of the Channel into the monitors. -pub trait ChannelKeys : Send+Clone + Writeable { +pub trait BaseSign { /// 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; + 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 @@ -245,7 +215,7 @@ pub trait ChannelKeys : Send+Clone + Writeable { fn pubkeys(&self) -> &ChannelPublicKeys; /// Gets an arbitrary identifier describing the set of keys which are provided back to you in /// some SpendableOutputDescriptor types. This should be sufficient to identify this - /// ChannelKeys object uniquely and lookup or re-derive its keys. + /// Sign object uniquely and lookup or re-derive its keys. fn channel_keys_id(&self) -> [u8; 32]; /// Create a signature for a counterparty's commitment transaction and associated HTLC transactions. @@ -253,7 +223,7 @@ pub trait ChannelKeys : Send+Clone + Writeable { /// Note that if signing fails or is rejected, the channel will be force-closed. // // 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), ()>; + fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; /// 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 @@ -269,21 +239,37 @@ pub trait ChannelKeys : Send+Clone + Writeable { // // TODO: Document the things someone using this interface should enforce before signing. // TODO: Key derivation failure should panic rather than Err - fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; /// Same as sign_holder_commitment, but exists only for tests to get access to holder commitment /// transactions which will be broadcasted later, after the channel has moved on to a newer /// state. Thus, needs its own method as sign_holder_commitment may enforce that we only ever /// get called once. #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))] - fn unsafe_sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + fn unsafe_sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + + /// Create a signature for the given input in a transaction spending an HTLC transaction output + /// or a commitment transaction `to_local` output when our counterparty broadcasts an old state. + /// + /// A justice transaction may claim multiple 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 multiple times for same output(s) if a fee-bump is needed with regards + /// to an upcoming timelock expiration. + /// + /// Amount is value of the output spent by this input, committed to in the BIP 143 signature. + /// + /// 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 _holder_ secret key and does + /// not allow the spending of any funds by itself (you need our holder revocation_secret to do + /// so). + fn sign_justice_revoked_output(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, secp_ctx: &Secp256k1) -> Result; - /// Create a signature for the given input in a transaction spending an HTLC or commitment - /// transaction output when our counterparty broadcasts an old state. + /// Create a signature for the given input in a transaction spending a commitment transaction + /// HTLC output when our counterparty broadcasts an old state. /// - /// A justice transaction may claim multiples outputs at the same time if timelocks are + /// A justice transaction may claim multiple 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 + /// It may be called multiple times for same output(s) if a fee-bump is needed with regards /// to an upcoming timelock expiration. /// /// Amount is value of the output spent by this input, committed to in the BIP 143 signature. @@ -293,10 +279,9 @@ pub trait ChannelKeys : Send+Clone + Writeable { /// not allow the spending of any funds by itself (you need our holder revocation_secret to do /// so). /// - /// 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; + /// htlc holds HTLC elements (hash, timelock), thus changing the format of the witness script + /// (which is committed to in the BIP 143 signatures). + fn sign_justice_revoked_htlc(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result; /// Create a signature for a claiming transaction for a HTLC output on a counterparty's commitment /// transaction, either offered or received. @@ -315,13 +300,13 @@ pub trait ChannelKeys : Send+Clone + Writeable { /// 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_counterparty_htlc_transaction(&self, htlc_tx: &Transaction, input: usize, amount: u64, per_commitment_point: &PublicKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result; + fn sign_counterparty_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. /// /// 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: &Transaction, secp_ctx: &Secp256k1) -> Result; /// Signs a channel announcement message with our funding key, proving it comes from one /// of the channel participants. @@ -329,7 +314,7 @@ pub trait ChannelKeys : Send+Clone + Writeable { /// Note that if this fails or is rejected, the channel will not be publicly announced and /// our counterparty may (though likely will not) close the channel on us for violating the /// protocol. - fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result; + fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result; /// Set the counterparty static channel data, including basepoints, /// counterparty_selected/holder_selected_contest_delay and funding outpoint. @@ -344,10 +329,18 @@ pub trait ChannelKeys : Send+Clone + Writeable { fn ready_channel(&mut self, channel_parameters: &ChannelTransactionParameters); } +/// A cloneable signer. +/// +/// Although we require signers to be cloneable, it may be useful for developers to be able to use +/// signers in an un-sized way, for example as `dyn BaseSign`. Therefore we separate the Clone trait, +/// which implies Sized, into this derived trait. +pub trait Sign: BaseSign + Writeable + Clone { +} + /// 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; +pub trait KeysInterface { + /// A type which implements Sign which will be returned by get_channel_signer. + type Signer : Sign; /// Get node secret key (aka node_id or network_key). /// @@ -364,11 +357,11 @@ pub trait KeysInterface: Send + Sync { /// 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; - /// Get a new set of ChannelKeys for per-channel secrets. These MUST be unique even if you + /// Get a new set of Sign for per-channel secrets. These MUST be unique even if you /// restarted with some stale data! /// /// This method must return a different value each time it is called. - fn get_channel_keys(&self, inbound: bool, channel_value_satoshis: u64) -> Self::ChanKeySigner; + fn get_channel_signer(&self, inbound: bool, channel_value_satoshis: u64) -> Self::Signer; /// Gets a unique, cryptographically-secure, random 32 byte value. This is used for encrypting /// onion packets and for temporary channel IDs. There is no requirement that these be /// persisted anywhere, though they must be unique across restarts. @@ -376,21 +369,27 @@ pub trait KeysInterface: Send + Sync { /// This method must return a different value each time it is called. fn get_secure_random_bytes(&self) -> [u8; 32]; - /// Reads a `ChanKeySigner` for this `KeysInterface` from the given input stream. + /// Reads a `Signer` for this `KeysInterface` from the given input stream. /// This is only called during deserialization of other objects which contain - /// `ChannelKeys`-implementing objects (ie `ChannelMonitor`s and `ChannelManager`s). - /// The bytes are exactly those which `::write()` writes, and + /// `Sign`-implementing objects (ie `ChannelMonitor`s and `ChannelManager`s). + /// The bytes are exactly those which `::write()` writes, and /// contain no versioning scheme. You may wish to include your own version prefix and ensure /// you've read all of the provided bytes to ensure no corruption occurred. - fn read_chan_signer(&self, reader: &[u8]) -> Result; + fn read_chan_signer(&self, reader: &[u8]) -> Result; + + /// Sign an invoice's preimage (note that this is the preimage of the invoice, not the HTLC's + /// preimage). By parameterizing by the preimage instead of the hash, we allow implementors of + /// this trait to parse the invoice and make sure they're signing what they expect, rather than + /// blindly signing the hash. + fn sign_invoice(&self, invoice_preimage: Vec) -> Result; } #[derive(Clone)] -/// A simple implementation of ChannelKeys that just keeps the private keys in memory. +/// A simple implementation of Sign that just keeps the private keys in memory. /// /// This implementation performs no policy checks and is insufficient by itself as /// a secure external signer. -pub struct InMemoryChannelKeys { +pub struct InMemorySigner { /// Private key of anchor tx pub funding_key: SecretKey, /// Holder secret key for blinded revocation pubkey @@ -413,8 +412,8 @@ pub struct InMemoryChannelKeys { channel_keys_id: [u8; 32], } -impl InMemoryChannelKeys { - /// Create a new InMemoryChannelKeys +impl InMemorySigner { + /// Create a new InMemorySigner pub fn new( secp_ctx: &Secp256k1, funding_key: SecretKey, @@ -424,12 +423,12 @@ impl InMemoryChannelKeys { htlc_base_key: SecretKey, commitment_seed: [u8; 32], channel_value_satoshis: u64, - channel_keys_id: [u8; 32]) -> InMemoryChannelKeys { + channel_keys_id: [u8; 32]) -> InMemorySigner { let holder_channel_pubkeys = - InMemoryChannelKeys::make_holder_keys(secp_ctx, &funding_key, &revocation_base_key, + InMemorySigner::make_holder_keys(secp_ctx, &funding_key, &revocation_base_key, &payment_key, &delayed_payment_base_key, &htlc_base_key); - InMemoryChannelKeys { + InMemorySigner { funding_key, revocation_base_key, payment_key, @@ -549,8 +548,8 @@ impl InMemoryChannelKeys { } } -impl ChannelKeys for InMemoryChannelKeys { - fn get_per_commitment_point(&self, idx: u64, secp_ctx: &Secp256k1) -> PublicKey { +impl BaseSign for InMemorySigner { + 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) } @@ -562,7 +561,7 @@ impl ChannelKeys for InMemoryChannelKeys { fn pubkeys(&self) -> &ChannelPublicKeys { &self.holder_channel_pubkeys } fn channel_keys_id(&self) -> [u8; 32] { self.channel_keys_id } - fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { + fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { let trusted_tx = commitment_tx.trust(); let keys = trusted_tx.keys(); @@ -578,17 +577,14 @@ impl ChannelKeys for InMemoryChannelKeys { 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_sighash = hash_to_message!(&bip143::SigHashCache::new(&htlc_tx).signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, SigHashType::All)[..]); - let holder_htlc_key = match chan_utils::derive_private_key(&secp_ctx, &keys.per_commitment_point, &self.htlc_base_key) { - Ok(s) => s, - Err(_) => return Err(()), - }; + 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)); } Ok((commitment_sig, htlc_sigs)) } - fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { + 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); let trusted_tx = commitment_tx.trust(); @@ -599,7 +595,7 @@ impl ChannelKeys for InMemoryChannelKeys { } #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))] - fn unsafe_sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { + fn unsafe_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); let trusted_tx = commitment_tx.trust(); @@ -609,39 +605,34 @@ impl ChannelKeys for InMemoryChannelKeys { Ok((sig, htlc_sigs)) } - 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(()) - }; + fn sign_justice_revoked_output(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, secp_ctx: &Secp256k1) -> Result { + let revocation_key = chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_key, &self.revocation_base_key).map_err(|_| ())?; let per_commitment_point = PublicKey::from_secret_key(secp_ctx, &per_commitment_key); - let revocation_pubkey = match chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &self.pubkeys().revocation_basepoint) { - Ok(revocation_pubkey) => revocation_pubkey, - Err(_) => return Err(()) + let revocation_pubkey = chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &self.pubkeys().revocation_basepoint).map_err(|_| ())?; + let witness_script = { + let counterparty_delayedpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().delayed_payment_basepoint).map_err(|_| ())?; + chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.holder_selected_contest_delay(), &counterparty_delayedpubkey) }; - let witness_script = if let &Some(ref htlc) = htlc { - let counterparty_htlcpubkey = match chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().htlc_basepoint) { - Ok(counterparty_htlcpubkey) => counterparty_htlcpubkey, - Err(_) => return Err(()) - }; - let holder_htlcpubkey = match chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.pubkeys().htlc_basepoint) { - Ok(holder_htlcpubkey) => holder_htlcpubkey, - Err(_) => return Err(()) - }; + let mut sighash_parts = bip143::SigHashCache::new(justice_tx); + let sighash = hash_to_message!(&sighash_parts.signature_hash(input, &witness_script, amount, SigHashType::All)[..]); + return Ok(secp_ctx.sign(&sighash, &revocation_key)) + } + + fn sign_justice_revoked_htlc(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result { + let revocation_key = chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_key, &self.revocation_base_key).map_err(|_| ())?; + let per_commitment_point = PublicKey::from_secret_key(secp_ctx, &per_commitment_key); + let revocation_pubkey = chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &self.pubkeys().revocation_basepoint).map_err(|_| ())?; + 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) - } else { - let counterparty_delayedpubkey = match chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().delayed_payment_basepoint) { - Ok(counterparty_delayedpubkey) => counterparty_delayedpubkey, - Err(_) => return Err(()) - }; - chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.holder_selected_contest_delay(), &counterparty_delayedpubkey) }; let mut sighash_parts = bip143::SigHashCache::new(justice_tx); let sighash = hash_to_message!(&sighash_parts.signature_hash(input, &witness_script, amount, SigHashType::All)[..]); return Ok(secp_ctx.sign(&sighash, &revocation_key)) } - fn sign_counterparty_htlc_transaction(&self, htlc_tx: &Transaction, input: usize, amount: u64, per_commitment_point: &PublicKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result { + fn sign_counterparty_htlc_transaction(&self, htlc_tx: &Transaction, input: usize, amount: u64, per_commitment_point: &PublicKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1) -> Result { if let Ok(htlc_key) = chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &self.htlc_base_key) { 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) { @@ -657,7 +648,7 @@ impl ChannelKeys for InMemoryChannelKeys { Err(()) } - fn sign_closing_transaction(&self, closing_tx: &Transaction, secp_ctx: &Secp256k1) -> Result { + 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(()); } @@ -670,7 +661,7 @@ impl ChannelKeys for InMemoryChannelKeys { Ok(secp_ctx.sign(&sighash, &self.funding_key)) } - fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result { + fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result { let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]); Ok(secp_ctx.sign(&msghash, &self.funding_key)) } @@ -682,8 +673,15 @@ impl ChannelKeys for InMemoryChannelKeys { } } -impl Writeable for InMemoryChannelKeys { +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)?; @@ -694,12 +692,16 @@ impl Writeable for InMemoryChannelKeys { self.channel_value_satoshis.write(writer)?; self.channel_keys_id.write(writer)?; + write_tlv_fields!(writer, {}); + Ok(()) } } -impl Readable for InMemoryChannelKeys { - fn read(reader: &mut R) -> Result { +impl Readable for InMemorySigner { + 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)?; @@ -710,12 +712,14 @@ impl Readable for InMemoryChannelKeys { let channel_value_satoshis = Readable::read(reader)?; let secp_ctx = Secp256k1::signing_only(); let holder_channel_pubkeys = - InMemoryChannelKeys::make_holder_keys(&secp_ctx, &funding_key, &revocation_base_key, + InMemorySigner::make_holder_keys(&secp_ctx, &funding_key, &revocation_base_key, &payment_key, &delayed_payment_base_key, &htlc_base_key); let keys_id = Readable::read(reader)?; - Ok(InMemoryChannelKeys { + read_tlv_fields!(reader, {}); + + Ok(InMemorySigner { funding_key, revocation_base_key, payment_key, @@ -738,14 +742,16 @@ impl Readable for InMemoryChannelKeys { /// Cooperative closes may use seed/2' /// The two close keys may be needed to claim on-chain funds! pub struct KeysManager { - secp_ctx: Secp256k1, + secp_ctx: Secp256k1, node_secret: SecretKey, destination_script: Script, shutdown_pubkey: PublicKey, channel_master_key: ExtendedPrivKey, channel_child_index: AtomicUsize, + rand_bytes_master_key: ExtendedPrivKey, rand_bytes_child_index: AtomicUsize, + rand_bytes_unique_start: Sha256State, seed: [u8; 32], starting_time_secs: u64, @@ -773,7 +779,7 @@ impl KeysManager { /// 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], starting_time_secs: u64, starting_time_nanos: u32) -> Self { - let secp_ctx = Secp256k1::signing_only(); + let secp_ctx = Secp256k1::new(); // Note that when we aren't serializing the key, network doesn't matter match ExtendedPrivKey::new_master(Network::Testnet, seed) { Ok(master_key) => { @@ -794,39 +800,44 @@ impl KeysManager { let channel_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(3).unwrap()).expect("Your RNG is busted"); let rand_bytes_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(4).unwrap()).expect("Your RNG is busted"); - KeysManager { + let mut rand_bytes_unique_start = Sha256::engine(); + rand_bytes_unique_start.input(&byte_utils::be64_to_array(starting_time_secs)); + rand_bytes_unique_start.input(&byte_utils::be32_to_array(starting_time_nanos)); + rand_bytes_unique_start.input(seed); + + let mut res = KeysManager { secp_ctx, node_secret, + destination_script, shutdown_pubkey, + channel_master_key, channel_child_index: AtomicUsize::new(0), + rand_bytes_master_key, rand_bytes_child_index: AtomicUsize::new(0), + rand_bytes_unique_start, seed: *seed, starting_time_secs, starting_time_nanos, - } + }; + let secp_seed = res.get_secure_random_bytes(); + res.secp_ctx.seeded_randomize(&secp_seed); + res }, Err(_) => panic!("Your rng is busted"), } } - fn derive_unique_start(&self) -> Sha256State { - let mut unique_start = Sha256::engine(); - unique_start.input(&byte_utils::be64_to_array(self.starting_time_secs)); - unique_start.input(&byte_utils::be32_to_array(self.starting_time_nanos)); - unique_start.input(&self.seed); - unique_start - } - /// Derive an old set of ChannelKeys for per-channel secrets based on a key derivation - /// parameters. + /// Derive an old Sign containing per-channel secrets based on a key derivation parameters. + /// /// Key derivation parameters are accessible through a per-channel secrets - /// ChannelKeys::channel_keys_id and is provided inside DynamicOuputP2WSH in case of + /// Sign::channel_keys_id and is provided inside DynamicOuputP2WSH in case of /// 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]) -> InMemoryChannelKeys { + 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); @@ -860,7 +871,7 @@ impl KeysManager { let delayed_payment_base_key = key_step!(b"delayed payment base key", payment_key); let htlc_base_key = key_step!(b"HTLC base key", delayed_payment_base_key); - InMemoryChannelKeys::new( + InMemorySigner::new( &self.secp_ctx, funding_key, revocation_base_key, @@ -883,8 +894,8 @@ impl KeysManager { /// We do not enforce that outputs meet the dust limit or that any output scripts are standard. /// /// May panic if the `SpendableOutputDescriptor`s were not generated by Channels which used - /// this KeysManager or one of the `InMemoryChannelKeys` created by this KeysManager. - pub fn spend_spendable_outputs(&self, descriptors: &[SpendableOutputDescriptor], outputs: Vec, change_destination_script: Script, feerate_sat_per_1000_weight: u32, secp_ctx: &Secp256k1) -> Result { + /// this KeysManager or one of the `InMemorySigner` created by this KeysManager. + pub fn spend_spendable_outputs(&self, descriptors: &[&SpendableOutputDescriptor], outputs: Vec, change_destination_script: Script, feerate_sat_per_1000_weight: u32, secp_ctx: &Secp256k1) -> Result { let mut input = Vec::new(); let mut input_value = 0; let mut witness_weight = 0; @@ -935,7 +946,7 @@ impl KeysManager { }; 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<(InMemoryChannelKeys, [u8; 32])> = None; + let mut keys_cache: Option<(InMemorySigner, [u8; 32])> = None; let mut input_idx = 0; for outp in descriptors { match outp { @@ -992,7 +1003,7 @@ impl KeysManager { } impl KeysInterface for KeysManager { - type ChanKeySigner = InMemoryChannelKeys; + type Signer = InMemorySigner; fn get_node_secret(&self) -> SecretKey { self.node_secret.clone() @@ -1006,9 +1017,9 @@ impl KeysInterface for KeysManager { self.shutdown_pubkey.clone() } - fn get_channel_keys(&self, _inbound: bool, channel_value_satoshis: u64) -> Self::ChanKeySigner { + 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)); @@ -1017,7 +1028,7 @@ impl KeysInterface for KeysManager { } fn get_secure_random_bytes(&self) -> [u8; 32] { - let mut sha = self.derive_unique_start(); + let mut sha = self.rand_bytes_unique_start.clone(); let child_ix = self.rand_bytes_child_index.fetch_add(1, Ordering::AcqRel); let child_privkey = self.rand_bytes_master_key.ckd_priv(&self.secp_ctx, ChildNumber::from_hardened_idx(child_ix as u32).expect("key space exhausted")).expect("Your RNG is busted"); @@ -1027,7 +1038,17 @@ impl KeysInterface for KeysManager { Sha256::from_engine(sha).into_inner() } - fn read_chan_signer(&self, reader: &[u8]) -> Result { - InMemoryChannelKeys::read(&mut std::io::Cursor::new(reader)) + fn read_chan_signer(&self, reader: &[u8]) -> Result { + InMemorySigner::read(&mut io::Cursor::new(reader)) } + + fn sign_invoice(&self, invoice_preimage: Vec) -> Result { + Ok(self.secp_ctx.sign_recoverable(&hash_to_message!(&Sha256::hash(&invoice_preimage)), &self.get_node_secret())) + } +} + +// Ensure that BaseSign can have a vtable +#[test] +pub fn dyn_sign() { + let _signer: Box; }