/// The revocation point specific to the commitment transaction which was broadcast. Used to
/// derive the witnessScript for this output.
pub revocation_pubkey: PublicKey,
- /// Arbitrary identification information returned by a call to [`BaseSign::channel_keys_id`].
+ /// Arbitrary identification information returned by a call to [`ChannelSigner::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.
pub outpoint: OutPoint,
/// The output which is referenced by the given outpoint.
pub output: TxOut,
- /// Arbitrary identification information returned by a call to [`BaseSign::channel_keys_id`].
+ /// Arbitrary identification information returned by a call to [`ChannelSigner::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.
///
/// To derive the delayed payment key which is used to sign this input, you must pass the
/// holder [`InMemorySigner::delayed_payment_base_key`] (i.e., the private key which corresponds to the
- /// [`ChannelPublicKeys::delayed_payment_basepoint`] in [`BaseSign::pubkeys`]) and the provided
+ /// [`ChannelPublicKeys::delayed_payment_basepoint`] in [`ChannelSigner::pubkeys`]) and the provided
/// [`DelayedPaymentOutputDescriptor::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
- /// [`ChannelPublicKeys::delayed_payment_basepoint`] which appears in [`BaseSign::pubkeys`].
+ /// [`ChannelPublicKeys::delayed_payment_basepoint`] which appears in [`ChannelSigner::pubkeys`].
///
/// To derive the [`DelayedPaymentOutputDescriptor::revocation_pubkey`] provided here (which is
/// used in the witness script generation), you must pass the counterparty
/// [`ChannelPublicKeys::revocation_basepoint`] (which appears in the call to
- /// [`BaseSign::provide_channel_parameters`]) and the provided
+ /// [`ChannelSigner::provide_channel_parameters`]) and the provided
/// [`DelayedPaymentOutputDescriptor::per_commitment_point`] to
/// [`chan_utils::derive_public_revocation_key`].
///
/// [`chan_utils::get_revokeable_redeemscript`].
DelayedPaymentOutput(DelayedPaymentOutputDescriptor),
/// An output to a P2WPKH, spendable exclusively by our payment key (i.e., the private key
- /// which corresponds to the `payment_point` in [`BaseSign::pubkeys`]). The witness
+ /// which corresponds to the `payment_point` in [`ChannelSigner::pubkeys`]). The witness
/// in the spending input is, thus, simply:
/// ```bitcoin
/// <BIP 143 signature> <payment key>
(2, StaticPaymentOutput),
);
-/// A trait to sign Lightning channel transactions as described in
-/// [BOLT 3](https://github.com/lightning/bolts/blob/master/03-transactions.md).
-///
-/// Signing services could be implemented on a hardware wallet and should implement signing
-/// policies in order to be secure. Please refer to the [VLS Policy
-/// Controls](https://gitlab.com/lightning-signer/validating-lightning-signer/-/blob/main/docs/policy-controls.md)
-/// for an example of such policies.
-pub trait BaseSign {
+/// A trait to handle Lightning channel key material without concretizing the channel type or
+/// the signature mechanism.
+pub trait ChannelSigner {
/// 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<secp256k1::All>) -> 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
/// 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
/// irrelevant or duplicate preimages.
fn validate_holder_commitment(&self, holder_tx: &HolderCommitmentTransaction,
preimages: Vec<PaymentPreimage>) -> Result<(), ()>;
+
/// Returns the holder's channel public keys and basepoints.
fn pubkeys(&self) -> &ChannelPublicKeys;
+
/// Returns 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
- /// [`BaseSign`] object uniquely and lookup or re-derive its keys.
+ /// [`EcdsaChannelSigner`] object uniquely and lookup or re-derive its keys.
fn channel_keys_id(&self) -> [u8; 32];
+
+ /// Set the counterparty static channel data, including basepoints,
+ /// `counterparty_selected`/`holder_selected_contest_delay` and funding outpoint.
+ ///
+ /// This data is static, and will never change for a channel once set. For a given [`ChannelSigner`]
+ /// instance, LDK will call this method exactly once - either immediately after construction
+ /// (not including if done via [`SignerProvider::read_chan_signer`]) or when the funding
+ /// information has been generated.
+ ///
+ /// channel_parameters.is_populated() MUST be true.
+ fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters);
+}
+
+/// A trait to sign Lightning channel transactions as described in
+/// [BOLT 3](https://github.com/lightning/bolts/blob/master/03-transactions.md).
+///
+/// Signing services could be implemented on a hardware wallet and should implement signing
+/// policies in order to be secure. Please refer to the [VLS Policy
+/// Controls](https://gitlab.com/lightning-signer/validating-lightning-signer/-/blob/main/docs/policy-controls.md)
+/// for an example of such policies.
+pub trait EcdsaChannelSigner: ChannelSigner {
/// 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.
fn sign_channel_announcement_with_funding_key(
&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>
) -> Result<Signature, ()>;
- /// Set the counterparty static channel data, including basepoints,
- /// `counterparty_selected`/`holder_selected_contest_delay` and funding outpoint.
- ///
- /// This data is static, and will never change for a channel once set. For a given [`BaseSign`]
- /// instance, LDK will call this method exactly once - either immediately after construction
- /// (not including if done via [`SignerProvider::read_chan_signer`]) or when the funding
- /// information has been generated.
- ///
- /// channel_parameters.is_populated() MUST be true.
- fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters);
}
/// A writeable signer.
///
/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
/// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
-pub trait Sign: BaseSign + Writeable {}
+pub trait WriteableEcdsaChannelSigner: EcdsaChannelSigner + Writeable {}
/// Specifies the recipient of an invoice.
///
/// A trait that can return signer instances for individual channels.
pub trait SignerProvider {
- /// A type which implements [`Sign`] which will be returned by [`Self::derive_channel_signer`].
- type Signer : Sign;
+ /// A type which implements [`WriteableEcdsaChannelSigner`] which will be returned by [`Self::derive_channel_signer`].
+ type Signer : WriteableEcdsaChannelSigner;
/// Generates a unique `channel_keys_id` that can be used to obtain a [`Self::Signer`] through
/// [`SignerProvider::derive_channel_signer`]. The `user_channel_id` is provided to allow
/// To derive a new `Signer`, a fresh `channel_keys_id` should be obtained through
/// [`SignerProvider::generate_channel_keys_id`]. Otherwise, an existing `Signer` can be
/// re-derived from its `channel_keys_id`, which can be obtained through its trait method
- /// [`BaseSign::channel_keys_id`].
+ /// [`ChannelSigner::channel_keys_id`].
fn derive_channel_signer(&self, channel_value_satoshis: u64, channel_keys_id: [u8; 32]) -> Self::Signer;
/// Reads a [`Signer`] for this [`SignerProvider`] from the given input stream.
/// This is only called during deserialization of other objects which contain
- /// [`Sign`]-implementing objects (i.e., [`ChannelMonitor`]s and [`ChannelManager`]s).
+ /// [`WriteableEcdsaChannelSigner`]-implementing objects (i.e., [`ChannelMonitor`]s and [`ChannelManager`]s).
/// The bytes are exactly those which `<Self::Signer as Writeable>::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.
}
#[derive(Clone)]
-/// A simple implementation of [`Sign`] that just keeps the private keys in memory.
+/// A simple implementation of [`WriteableEcdsaChannelSigner`] that just keeps the private keys in memory.
///
/// This implementation performs no policy checks and is insufficient by itself as
/// a secure external signer.
/// Returns the counterparty's pubkeys.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn counterparty_pubkeys(&self) -> &ChannelPublicKeys { &self.get_channel_parameters().counterparty_parameters.as_ref().unwrap().pubkeys }
/// Returns the `contest_delay` value specified by our counterparty and applied on holder-broadcastable
/// transactions, i.e., the amount of time that we have to wait to recover our funds if we
/// broadcast a transaction.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn counterparty_selected_contest_delay(&self) -> u16 { self.get_channel_parameters().counterparty_parameters.as_ref().unwrap().selected_contest_delay }
/// Returns the `contest_delay` value specified by us and applied on transactions broadcastable
/// by our counterparty, i.e., the amount of time that they have to wait to recover their funds
/// if they broadcast a transaction.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn holder_selected_contest_delay(&self) -> u16 { self.get_channel_parameters().holder_selected_contest_delay }
/// Returns whether the holder is the initiator.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn is_outbound(&self) -> bool { self.get_channel_parameters().is_outbound_from_holder }
/// Funding outpoint
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn funding_outpoint(&self) -> &OutPoint { self.get_channel_parameters().funding_outpoint.as_ref().unwrap() }
/// Returns a [`ChannelTransactionParameters`] for this channel, to be used when verifying or
/// building transactions.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn get_channel_parameters(&self) -> &ChannelTransactionParameters {
self.channel_parameters.as_ref().unwrap()
}
/// Returns whether anchors should be used.
///
- /// Will panic if [`BaseSign::provide_channel_parameters`] has not been called before.
+ /// Will panic if [`ChannelSigner::provide_channel_parameters`] has not been called before.
pub fn opt_anchors(&self) -> bool {
self.get_channel_parameters().opt_anchors.is_some()
}
}
}
-impl BaseSign for InMemorySigner {
+impl ChannelSigner for InMemorySigner {
fn get_per_commitment_point(&self, idx: u64, secp_ctx: &Secp256k1<secp256k1::All>) -> 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 channel_keys_id(&self) -> [u8; 32] { self.channel_keys_id }
+ fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters) {
+ assert!(self.channel_parameters.is_none() || self.channel_parameters.as_ref().unwrap() == channel_parameters);
+ if self.channel_parameters.is_some() {
+ // The channel parameters were already set and they match, return early.
+ return;
+ }
+ assert!(channel_parameters.is_populated(), "Channel parameters must be fully populated");
+ self.channel_parameters = Some(channel_parameters.clone());
+ }
+}
+
+impl EcdsaChannelSigner for InMemorySigner {
fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, _preimages: Vec<PaymentPreimage>, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()> {
let trusted_tx = commitment_tx.trust();
let keys = trusted_tx.keys();
let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
Ok(sign(secp_ctx, &msghash, &self.funding_key))
}
-
- fn provide_channel_parameters(&mut self, channel_parameters: &ChannelTransactionParameters) {
- assert!(self.channel_parameters.is_none() || self.channel_parameters.as_ref().unwrap() == channel_parameters);
- if self.channel_parameters.is_some() {
- // The channel parameters were already set and they match, return early.
- return;
- }
- assert!(channel_parameters.is_populated(), "Channel parameters must be fully populated");
- self.channel_parameters = Some(channel_parameters.clone());
- }
}
const SERIALIZATION_VERSION: u8 = 1;
const MIN_SERIALIZATION_VERSION: u8 = 1;
-impl Sign for InMemorySigner {}
+impl WriteableEcdsaChannelSigner for InMemorySigner {}
impl Writeable for InMemorySigner {
fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
Err(_) => panic!("Your rng is busted"),
}
}
- /// Derive an old [`Sign`] containing per-channel secrets based on a key derivation parameters.
+ /// Derive an old [`WriteableEcdsaChannelSigner`] containing per-channel secrets based on a key derivation parameters.
pub fn derive_channel_keys(&self, channel_value_satoshis: u64, params: &[u8; 32]) -> InMemorySigner {
let chan_id = u64::from_be_bytes(params[0..8].try_into().unwrap());
let mut unique_start = Sha256::engine();
}
}
-// Ensure that BaseSign can have a vtable
+// Ensure that EcdsaChannelSigner can have a vtable
#[test]
pub fn dyn_sign() {
- let _signer: Box<dyn BaseSign>;
+ let _signer: Box<dyn EcdsaChannelSigner>;
}
projects / rust-lightning / blobdiff