X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fkeysinterface.rs;h=c001646263fdf0d7ae4e1f1c079ed02ab3b40135;hb=09d2a71352f738de1f4f36248a735e6383ee0d8d;hp=2a68299c248caabc0045244d3e8cb03a5fa6d7f1;hpb=b1ed0ee0339db7cb1820c14a920d294a264037c7;p=rust-lightning diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index 2a68299c..c0016462 100644 --- a/lightning/src/chain/keysinterface.rs +++ b/lightning/src/chain/keysinterface.rs @@ -24,7 +24,7 @@ use util::logger::Logger; use util::ser::Writeable; use ln::chan_utils; -use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment}; +use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment, make_funding_redeemscript}; use ln::msgs; use std::sync::Arc; @@ -142,7 +142,13 @@ pub trait ChannelKeys : Send { /// 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, channel_value_satoshis: u64, channel_funding_script: &Script, 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, channel_value_satoshis: u64, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()>; + + /// 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, channel_value_satoshis: u64, channel_funding_redeemscript: &Script, 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. @@ -151,6 +157,12 @@ pub trait ChannelKeys : Send { /// our counterparty may (though likely will not) close the channel on us for violating the /// protocol. fn sign_channel_announcement(&self, msg: &msgs::UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result; + + /// Set the remote funding key. This is done immediately on incoming channels + /// and as soon as the channel is accepted on outgoing channels. + /// + /// Will be called before any signatures are applied. + fn set_remote_funding_pubkey(&mut self, key: &PublicKey); } #[derive(Clone)] @@ -168,6 +180,8 @@ pub struct InMemoryChannelKeys { pub htlc_base_key: SecretKey, /// Commitment seed pub commitment_seed: [u8; 32], + /// Remote funding pubkey + pub remote_funding_pubkey: Option, } impl ChannelKeys for InMemoryChannelKeys { @@ -178,9 +192,14 @@ impl ChannelKeys for InMemoryChannelKeys { fn htlc_base_key(&self) -> &SecretKey { &self.htlc_base_key } fn commitment_seed(&self) -> &[u8; 32] { &self.commitment_seed } - fn sign_remote_commitment(&self, channel_value_satoshis: u64, channel_funding_script: &Script, 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, channel_value_satoshis: u64, feerate_per_kw: u64, commitment_tx: &Transaction, keys: &TxCreationKeys, htlcs: &[&HTLCOutputInCommitment], to_self_delay: u16, secp_ctx: &Secp256k1) -> Result<(Signature, Vec), ()> { if commitment_tx.input.len() != 1 { return Err(()); } - let commitment_sighash = hash_to_message!(&bip143::SighashComponents::new(&commitment_tx).sighash_all(&commitment_tx.input[0], &channel_funding_script, channel_value_satoshis)[..]); + + let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key); + let remote_funding_pubkey = self.remote_funding_pubkey.as_ref().expect("must set remote funding key before signing"); + let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, remote_funding_pubkey); + + let commitment_sighash = hash_to_message!(&bip143::SighashComponents::new(&commitment_tx).sighash_all(&commitment_tx.input[0], &channel_funding_redeemscript, channel_value_satoshis)[..]); let commitment_sig = secp_ctx.sign(&commitment_sighash, &self.funding_key); let commitment_txid = commitment_tx.txid(); @@ -202,10 +221,25 @@ impl ChannelKeys for InMemoryChannelKeys { Ok((commitment_sig, htlc_sigs)) } + fn sign_closing_transaction(&self, channel_value_satoshis: u64, channel_funding_redeemscript: &Script, 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(()); } + + let sighash = hash_to_message!(&bip143::SighashComponents::new(closing_tx) + .sighash_all(&closing_tx.input[0], &channel_funding_redeemscript, channel_value_satoshis)[..]); + Ok(secp_ctx.sign(&sighash, &self.funding_key)) + } + fn sign_channel_announcement(&self, msg: &msgs::UnsignedChannelAnnouncement, secp_ctx: &Secp256k1) -> Result { let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]); Ok(secp_ctx.sign(&msghash, &self.funding_key)) } + + fn set_remote_funding_pubkey(&mut self, key: &PublicKey) { + assert!(self.remote_funding_pubkey.is_none(), "Already set remote funding key"); + self.remote_funding_pubkey = Some(*key); + } } impl_writeable!(InMemoryChannelKeys, 0, { @@ -214,7 +248,8 @@ impl_writeable!(InMemoryChannelKeys, 0, { payment_base_key, delayed_payment_base_key, htlc_base_key, - commitment_seed + commitment_seed, + remote_funding_pubkey }); /// Simple KeysInterface implementor that takes a 32-byte seed for use as a BIP 32 extended key @@ -363,6 +398,7 @@ impl KeysInterface for KeysManager { delayed_payment_base_key, htlc_base_key, commitment_seed, + remote_funding_pubkey: None, } }