X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fkeysinterface.rs;h=366afe0db0969b9f757302b2df256c27767dec55;hb=refs%2Ftags%2Fv0.0.14;hp=9d3b955861dbfca672fabf614ab4378f58aaa6a7;hpb=94bb0c9128c2635ea08ec089f79fab04880dedd0;p=rust-lightning diff --git a/lightning/src/chain/keysinterface.rs b/lightning/src/chain/keysinterface.rs index 9d3b9558..366afe0d 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}; @@ -226,11 +227,11 @@ impl Readable for SpendableOutputDescriptor { /// of LN security model, orthogonal of key management issues. // 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 Sign : 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 @@ -253,7 +254,7 @@ pub trait Sign : 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 @@ -269,14 +270,14 @@ pub trait Sign : 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 or commitment /// transaction output when our counterparty broadcasts an old state. @@ -296,7 +297,7 @@ pub trait Sign : Send+Clone + Writeable { /// 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; + 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 counterparty's commitment /// transaction, either offered or received. @@ -315,13 +316,13 @@ pub trait Sign : 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 +330,7 @@ pub trait Sign : 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. @@ -344,8 +345,16 @@ pub trait Sign : 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 { +pub trait KeysInterface { /// A type which implements Sign which will be returned by get_channel_signer. type Signer : Sign; @@ -383,6 +392,12 @@ pub trait KeysInterface: Send + Sync { /// 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; + + /// 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)] @@ -549,8 +564,8 @@ impl InMemorySigner { } } -impl Sign for InMemorySigner { - 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 +577,7 @@ impl Sign for InMemorySigner { 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(); @@ -588,7 +603,7 @@ impl Sign for InMemorySigner { 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 +614,7 @@ impl Sign for InMemorySigner { } #[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(); @@ -609,7 +624,7 @@ impl Sign for InMemorySigner { 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 { + 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(()) @@ -641,7 +656,7 @@ impl Sign for InMemorySigner { 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 +672,7 @@ impl Sign for InMemorySigner { 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 +685,7 @@ impl Sign for InMemorySigner { 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)) } @@ -682,6 +697,8 @@ impl Sign for InMemorySigner { } } +impl Sign for InMemorySigner {} + impl Writeable for InMemorySigner { fn write(&self, writer: &mut W) -> Result<(), Error> { self.funding_key.write(writer)?; @@ -738,14 +755,16 @@ impl Readable for InMemorySigner { /// 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 +792,7 @@ 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) => { @@ -794,33 +813,38 @@ 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 Sign 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 /// 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. @@ -1017,7 +1041,7 @@ 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"); @@ -1030,4 +1054,14 @@ impl KeysInterface for KeysManager { fn read_chan_signer(&self, reader: &[u8]) -> Result { InMemorySigner::read(&mut std::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; }