+++ /dev/null
-// This file is Copyright its original authors, visible in version control
-// history.
-//
-// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
-// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
-// You may not use this file except in accordance with one or both of these
-// licenses.
-
-//! Provides keys to LDK and defines some useful objects describing spendable on-chain outputs.
-//!
-//! The provided output descriptors follow a custom LDK data format and are currently not fully
-//! compatible with Bitcoin Core output descriptors.
-
-use bitcoin::blockdata::transaction::{Transaction, TxOut, TxIn, EcdsaSighashType};
-use bitcoin::blockdata::script::{Script, Builder};
-use bitcoin::blockdata::opcodes;
-use bitcoin::network::constants::Network;
-use bitcoin::util::bip32::{ExtendedPrivKey, ExtendedPubKey, ChildNumber};
-use bitcoin::util::sighash;
-
-use bitcoin::bech32::u5;
-use bitcoin::hashes::{Hash, HashEngine};
-use bitcoin::hashes::sha256::Hash as Sha256;
-use bitcoin::hashes::sha256d::Hash as Sha256dHash;
-use bitcoin::hash_types::WPubkeyHash;
-
-use bitcoin::secp256k1::{SecretKey, PublicKey, Scalar};
-use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature, Signing};
-use bitcoin::secp256k1::ecdh::SharedSecret;
-use bitcoin::secp256k1::ecdsa::RecoverableSignature;
-use bitcoin::{PackedLockTime, secp256k1, Sequence, Witness};
-
-use crate::util::transaction_utils;
-use crate::util::crypto::{hkdf_extract_expand_twice, sign, sign_with_aux_rand};
-use crate::util::ser::{Writeable, Writer, Readable, ReadableArgs};
-use crate::chain::transaction::OutPoint;
-#[cfg(anchors)]
-use crate::events::bump_transaction::HTLCDescriptor;
-use crate::ln::channel::ANCHOR_OUTPUT_VALUE_SATOSHI;
-use crate::ln::{chan_utils, PaymentPreimage};
-use crate::ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, HolderCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction, ClosingTransaction};
-use crate::ln::msgs::{UnsignedChannelAnnouncement, UnsignedGossipMessage};
-use crate::ln::script::ShutdownScript;
-
-use crate::prelude::*;
-use core::convert::TryInto;
-use core::ops::Deref;
-use core::sync::atomic::{AtomicUsize, Ordering};
-use crate::io::{self, Error};
-use crate::ln::msgs::{DecodeError, MAX_VALUE_MSAT};
-use crate::util::atomic_counter::AtomicCounter;
-use crate::util::chacha20::ChaCha20;
-use crate::util::invoice::construct_invoice_preimage;
-
-/// Used as initial key material, to be expanded into multiple secret keys (but not to be used
-/// directly). This is used within LDK to encrypt/decrypt inbound payment data.
-///
-/// This is not exported to bindings users as we just use `[u8; 32]` directly
-#[derive(Hash, Copy, Clone, PartialEq, Eq, Debug)]
-pub struct KeyMaterial(pub [u8; 32]);
-
-/// Information about a spendable output to a P2WSH script.
-///
-/// See [`SpendableOutputDescriptor::DelayedPaymentOutput`] for more details on how to spend this.
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub struct DelayedPaymentOutputDescriptor {
- /// The outpoint which is spendable.
- pub outpoint: OutPoint,
- /// Per commitment point to derive the delayed payment key by key holder.
- pub per_commitment_point: PublicKey,
- /// The `nSequence` value which must be set in the spending input to satisfy the `OP_CSV` in
- /// the witness_script.
- pub to_self_delay: u16,
- /// The output which is referenced by the given outpoint.
- pub output: TxOut,
- /// 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 [`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 channel_value_satoshis: u64,
-}
-impl DelayedPaymentOutputDescriptor {
- /// The maximum length a well-formed witness spending one of these should have.
- /// Note: If you have the grind_signatures feature enabled, this will be at least 1 byte
- /// shorter.
- // Calculated as 1 byte length + 73 byte signature, 1 byte empty vec push, 1 byte length plus
- // redeemscript push length.
- 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, Eq)]
-pub struct StaticPaymentOutputDescriptor {
- /// The outpoint which is spendable.
- pub outpoint: OutPoint,
- /// The output which is referenced by the given outpoint.
- pub output: TxOut,
- /// 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.
- pub channel_value_satoshis: u64,
-}
-impl StaticPaymentOutputDescriptor {
- /// The maximum length a well-formed witness spending one of these should have.
- /// Note: If you have the grind_signatures feature enabled, this will be at least 1 byte
- /// shorter.
- // Calculated as 1 byte legnth + 73 byte signature, 1 byte empty vec push, 1 byte length plus
- // 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),
-});
-
-/// Describes the necessary information to spend a spendable output.
-///
-/// When on-chain outputs are created by LDK (which our counterparty is not able to claim at any
-/// point in the future) a [`SpendableOutputs`] event is generated which you must track and be able
-/// to spend on-chain. The information needed to do this is provided in this enum, including the
-/// outpoint describing which `txid` and output `index` is available, the full output which exists
-/// at that `txid`/`index`, and any keys or other information required to sign.
-///
-/// [`SpendableOutputs`]: crate::events::Event::SpendableOutputs
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub enum SpendableOutputDescriptor {
- /// An output to a script which was provided via [`SignerProvider`] directly, either from
- /// [`get_destination_script`] or [`get_shutdown_scriptpubkey`], thus you should already
- /// know how to spend it. No secret keys are provided as LDK was never given any key.
- /// These may include outputs from a transaction punishing our counterparty or claiming an HTLC
- /// on-chain using the payment preimage or after it has timed out.
- ///
- /// [`get_shutdown_scriptpubkey`]: SignerProvider::get_shutdown_scriptpubkey
- /// [`get_destination_script`]: SignerProvider::get_shutdown_scriptpubkey
- StaticOutput {
- /// The outpoint which is spendable.
- outpoint: OutPoint,
- /// The output which is referenced by the given outpoint.
- output: TxOut,
- },
- /// An output to a P2WSH script which can be spent with a single signature after an `OP_CSV`
- /// delay.
- ///
- /// The witness in the spending input should be:
- /// ```bitcoin
- /// <BIP 143 signature> <empty vector> (MINIMALIF standard rule) <provided witnessScript>
- /// ```
- ///
- /// Note that the `nSequence` field in the spending input must be set to
- /// [`DelayedPaymentOutputDescriptor::to_self_delay`] (which means the transaction is not
- /// broadcastable until at least [`DelayedPaymentOutputDescriptor::to_self_delay`] blocks after
- /// the outpoint confirms, see [BIP
- /// 68](https://github.com/bitcoin/bips/blob/master/bip-0068.mediawiki)). Also note that LDK
- /// won't generate a [`SpendableOutputDescriptor`] until the corresponding block height
- /// is reached.
- ///
- /// These are generally the result of a "revocable" output to us, spendable only by us unless
- /// it is an output from an old state which we broadcast (which should never happen).
- ///
- /// 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 [`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 [`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
- /// [`ChannelSigner::provide_channel_parameters`]) and the provided
- /// [`DelayedPaymentOutputDescriptor::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
- /// regenerated by passing the [`DelayedPaymentOutputDescriptor::revocation_pubkey`] (derived
- /// as explained above), our delayed payment pubkey (derived as explained above), and the
- /// [`DelayedPaymentOutputDescriptor::to_self_delay`] contained here to
- /// [`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 [`ChannelSigner::pubkeys`]). The witness
- /// in the spending input is, thus, simply:
- /// ```bitcoin
- /// <BIP 143 signature> <payment key>
- /// ```
- ///
- /// These are generally the result of our counterparty having broadcast the current state,
- /// allowing us to claim the non-HTLC-encumbered outputs immediately.
- StaticPaymentOutput(StaticPaymentOutputDescriptor),
-}
-
-impl_writeable_tlv_based_enum!(SpendableOutputDescriptor,
- (0, StaticOutput) => {
- (0, outpoint, required),
- (2, output, required),
- },
-;
- (1, DelayedPaymentOutput),
- (2, StaticPaymentOutput),
-);
-
-/// 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
- /// 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];
-
- /// 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
- /// secret won't leave us without a broadcastable holder transaction.
- /// Policy checks should be implemented in this function, including checking the amount
- /// sent to us and checking the HTLCs.
- ///
- /// The preimages of outgoing HTLCs that were fulfilled since the last commitment are provided.
- /// A validating signer should ensure that an HTLC output is removed only when the matching
- /// preimage is provided, or when the value to holder is restored.
- ///
- /// Note that all the relevant preimages will be provided, but there may also be additional
- /// 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
- /// [`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.
- ///
- /// Policy checks should be implemented in this function, including checking the amount
- /// sent to us and checking the HTLCs.
- ///
- /// The preimages of outgoing HTLCs that were fulfilled since the last commitment are provided.
- /// A validating signer should ensure that an HTLC output is removed only when the matching
- /// preimage is provided, or when the value to holder is restored.
- ///
- /// Note that all the relevant preimages will be provided, but there may also be additional
- /// irrelevant or duplicate preimages.
- //
- // TODO: Document the things someone using this interface should enforce before signing.
- fn sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction,
- preimages: Vec<PaymentPreimage>, secp_ctx: &Secp256k1<secp256k1::All>
- ) -> Result<(Signature, Vec<Signature>), ()>;
- /// Validate the counterparty's revocation.
- ///
- /// This is required in order for the signer to make sure that the state has moved
- /// forward and it is safe to sign the next counterparty commitment.
- fn validate_counterparty_revocation(&self, idx: u64, secret: &SecretKey) -> Result<(), ()>;
- /// Creates a signature for a holder's commitment transaction and its claiming HTLC transactions.
- ///
- /// This will be called
- /// - with a non-revoked `commitment_tx`.
- /// - with the latest `commitment_tx` when we initiate a force-close.
- /// - with the previous `commitment_tx`, just to get claiming HTLC
- /// signatures, if we are reacting to a [`ChannelMonitor`]
- /// [replica](https://github.com/lightningdevkit/rust-lightning/blob/main/GLOSSARY.md#monitor-replicas)
- /// that decided to broadcast before it had been updated to the latest `commitment_tx`.
- ///
- /// This may be called multiple times for the same transaction.
- ///
- /// An external signer implementation should check that the commitment has not been revoked.
- ///
- /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
- // TODO: Document the things someone using this interface should enforce before signing.
- fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction,
- secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()>;
- /// Same as [`sign_holder_commitment_and_htlcs`], 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_and_htlcs`] 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<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()>;
- /// 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<secp256k1::All>
- ) -> Result<Signature, ()>;
- /// 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 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 the 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).
- ///
- /// `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<secp256k1::All>) -> Result<Signature, ()>;
- #[cfg(anchors)]
- /// Computes the signature for a commitment transaction's HTLC output used as an input within
- /// `htlc_tx`, which spends the commitment transaction at index `input`. The signature returned
- /// must be be computed using [`EcdsaSighashType::All`]. Note that this should only be used to
- /// sign HTLC transactions from channels supporting anchor outputs after all additional
- /// inputs/outputs have been added to the transaction.
- ///
- /// [`EcdsaSighashType::All`]: bitcoin::blockdata::transaction::EcdsaSighashType::All
- fn sign_holder_htlc_transaction(&self, htlc_tx: &Transaction, input: usize,
- htlc_descriptor: &HTLCDescriptor, secp_ctx: &Secp256k1<secp256k1::All>
- ) -> Result<Signature, ()>;
- /// Create a signature for a claiming transaction for a HTLC output on a counterparty's commitment
- /// transaction, either offered or received.
- ///
- /// 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 an offered or received script as defined in BOLT3 for HTLC
- /// outputs.
- ///
- /// `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 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<secp256k1::All>) -> Result<Signature, ()>;
- /// 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: &ClosingTransaction,
- secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()>;
- /// Computes the signature for a commitment transaction's anchor output used as an
- /// input within `anchor_tx`, which spends the commitment transaction, at index `input`.
- fn sign_holder_anchor_input(
- &self, anchor_tx: &Transaction, input: usize, secp_ctx: &Secp256k1<secp256k1::All>,
- ) -> Result<Signature, ()>;
- /// Signs a channel announcement message with our funding key proving it comes from one of the
- /// channel participants.
- ///
- /// Channel announcements also require a signature from each node's network key. Our node
- /// signature is computed through [`NodeSigner::sign_gossip_message`].
- ///
- /// 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_with_funding_key(
- &self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>
- ) -> Result<Signature, ()>;
-}
-
-/// A writeable signer.
-///
-/// There will always be two instances of a signer per channel, one occupied by the
-/// [`ChannelManager`] and another by the channel's [`ChannelMonitor`].
-///
-/// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
-/// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
-pub trait WriteableEcdsaChannelSigner: EcdsaChannelSigner + Writeable {}
-
-/// Specifies the recipient of an invoice.
-///
-/// This indicates to [`NodeSigner::sign_invoice`] what node secret key should be used to sign
-/// the invoice.
-pub enum Recipient {
- /// The invoice should be signed with the local node secret key.
- Node,
- /// The invoice should be signed with the phantom node secret key. This secret key must be the
- /// same for all nodes participating in the [phantom node payment].
- ///
- /// [phantom node payment]: PhantomKeysManager
- PhantomNode,
-}
-
-/// A trait that describes a source of entropy.
-pub trait EntropySource {
- /// Gets a unique, cryptographically-secure, random 32-byte value. This method must return a
- /// different value each time it is called.
- fn get_secure_random_bytes(&self) -> [u8; 32];
-}
-
-/// A trait that can handle cryptographic operations at the scope level of a node.
-pub trait NodeSigner {
- /// Get secret key material as bytes for use in encrypting and decrypting inbound payment data.
- ///
- /// If the implementor of this trait supports [phantom node payments], then every node that is
- /// intended to be included in the phantom invoice route hints must return the same value from
- /// this method.
- // This is because LDK avoids storing inbound payment data by encrypting payment data in the
- // payment hash and/or payment secret, therefore for a payment to be receivable by multiple
- // nodes, they must share the key that encrypts this payment data.
- ///
- /// This method must return the same value each time it is called.
- ///
- /// [phantom node payments]: PhantomKeysManager
- fn get_inbound_payment_key_material(&self) -> KeyMaterial;
-
- /// Get node id based on the provided [`Recipient`].
- ///
- /// This method must return the same value each time it is called with a given [`Recipient`]
- /// parameter.
- ///
- /// Errors if the [`Recipient`] variant is not supported by the implementation.
- fn get_node_id(&self, recipient: Recipient) -> Result<PublicKey, ()>;
-
- /// Gets the ECDH shared secret of our node secret and `other_key`, multiplying by `tweak` if
- /// one is provided. Note that this tweak can be applied to `other_key` instead of our node
- /// secret, though this is less efficient.
- ///
- /// Note that if this fails while attempting to forward an HTLC, LDK will panic. The error
- /// should be resolved to allow LDK to resume forwarding HTLCs.
- ///
- /// Errors if the [`Recipient`] variant is not supported by the implementation.
- fn ecdh(&self, recipient: Recipient, other_key: &PublicKey, tweak: Option<&Scalar>) -> Result<SharedSecret, ()>;
-
- /// Sign an invoice.
- ///
- /// By parameterizing by the raw invoice bytes 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.
- ///
- /// The `hrp_bytes` are ASCII bytes, while the `invoice_data` is base32.
- ///
- /// The secret key used to sign the invoice is dependent on the [`Recipient`].
- ///
- /// Errors if the [`Recipient`] variant is not supported by the implementation.
- fn sign_invoice(&self, hrp_bytes: &[u8], invoice_data: &[u5], recipient: Recipient) -> Result<RecoverableSignature, ()>;
-
- /// Sign a gossip message.
- ///
- /// Note that if this fails, LDK may panic and the message will not be broadcast to the network
- /// or a possible channel counterparty. If LDK panics, the error should be resolved to allow the
- /// message to be broadcast, as otherwise it may prevent one from receiving funds over the
- /// corresponding channel.
- fn sign_gossip_message(&self, msg: UnsignedGossipMessage) -> Result<Signature, ()>;
-}
-
-/// A trait that can return signer instances for individual channels.
-pub trait SignerProvider {
- /// 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
- /// implementations of [`SignerProvider`] to maintain a mapping between itself and the generated
- /// `channel_keys_id`.
- ///
- /// This method must return a different value each time it is called.
- fn generate_channel_keys_id(&self, inbound: bool, channel_value_satoshis: u64, user_channel_id: u128) -> [u8; 32];
-
- /// Derives the private key material backing a `Signer`.
- ///
- /// 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
- /// [`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
- /// [`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.
- ///
- /// This method is slowly being phased out -- it will only be called when reading objects
- /// written by LDK versions prior to 0.0.113.
- ///
- /// [`Signer`]: Self::Signer
- /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
- /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
- fn read_chan_signer(&self, reader: &[u8]) -> Result<Self::Signer, DecodeError>;
-
- /// Get a script pubkey which we send funds to when claiming on-chain contestable outputs.
- ///
- /// If this function returns an error, this will result in a channel failing to open.
- ///
- /// 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_destination_script(&self) -> Result<Script, ()>;
-
- /// Get a script pubkey which we will send funds to when closing a channel.
- ///
- /// If this function returns an error, this will result in a channel failing to open or close.
- /// In the event of a failure when the counterparty is initiating a close, this can result in a
- /// channel force close.
- ///
- /// 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_scriptpubkey(&self) -> Result<ShutdownScript, ()>;
-}
-
-/// 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.
-pub struct InMemorySigner {
- /// Holder secret key in the 2-of-2 multisig script of a channel. This key also backs the
- /// holder's anchor output in a commitment transaction, if one is present.
- pub funding_key: SecretKey,
- /// Holder secret key for blinded revocation pubkey.
- pub revocation_base_key: SecretKey,
- /// Holder secret key used for our balance in counterparty-broadcasted commitment transactions.
- pub payment_key: SecretKey,
- /// Holder secret key used in an HTLC transaction.
- pub delayed_payment_base_key: SecretKey,
- /// Holder HTLC secret key used in commitment transaction HTLC outputs.
- pub htlc_base_key: SecretKey,
- /// Commitment seed.
- pub commitment_seed: [u8; 32],
- /// Holder public keys and basepoints.
- pub(crate) holder_channel_pubkeys: ChannelPublicKeys,
- /// Counterparty public keys and counterparty/holder `selected_contest_delay`, populated on channel acceptance.
- channel_parameters: Option<ChannelTransactionParameters>,
- /// The total value of this channel.
- channel_value_satoshis: u64,
- /// Key derivation parameters.
- channel_keys_id: [u8; 32],
- /// Seed from which all randomness produced is derived from.
- rand_bytes_unique_start: [u8; 32],
- /// Tracks the number of times we've produced randomness to ensure we don't return the same
- /// bytes twice.
- rand_bytes_index: AtomicCounter,
-}
-
-impl Clone for InMemorySigner {
- fn clone(&self) -> Self {
- Self {
- funding_key: self.funding_key.clone(),
- revocation_base_key: self.revocation_base_key.clone(),
- payment_key: self.payment_key.clone(),
- delayed_payment_base_key: self.delayed_payment_base_key.clone(),
- htlc_base_key: self.htlc_base_key.clone(),
- commitment_seed: self.commitment_seed.clone(),
- holder_channel_pubkeys: self.holder_channel_pubkeys.clone(),
- channel_parameters: self.channel_parameters.clone(),
- channel_value_satoshis: self.channel_value_satoshis,
- channel_keys_id: self.channel_keys_id,
- rand_bytes_unique_start: self.get_secure_random_bytes(),
- rand_bytes_index: AtomicCounter::new(),
- }
- }
-}
-
-impl InMemorySigner {
- /// Creates a new [`InMemorySigner`].
- pub fn new<C: Signing>(
- secp_ctx: &Secp256k1<C>,
- funding_key: SecretKey,
- revocation_base_key: SecretKey,
- payment_key: SecretKey,
- delayed_payment_base_key: SecretKey,
- htlc_base_key: SecretKey,
- commitment_seed: [u8; 32],
- channel_value_satoshis: u64,
- channel_keys_id: [u8; 32],
- rand_bytes_unique_start: [u8; 32],
- ) -> InMemorySigner {
- let holder_channel_pubkeys =
- InMemorySigner::make_holder_keys(secp_ctx, &funding_key, &revocation_base_key,
- &payment_key, &delayed_payment_base_key,
- &htlc_base_key);
- InMemorySigner {
- funding_key,
- revocation_base_key,
- payment_key,
- delayed_payment_base_key,
- htlc_base_key,
- commitment_seed,
- channel_value_satoshis,
- holder_channel_pubkeys,
- channel_parameters: None,
- channel_keys_id,
- rand_bytes_unique_start,
- rand_bytes_index: AtomicCounter::new(),
- }
- }
-
- fn make_holder_keys<C: Signing>(secp_ctx: &Secp256k1<C>,
- funding_key: &SecretKey,
- revocation_base_key: &SecretKey,
- payment_key: &SecretKey,
- delayed_payment_base_key: &SecretKey,
- htlc_base_key: &SecretKey) -> ChannelPublicKeys {
- let from_secret = |s: &SecretKey| PublicKey::from_secret_key(secp_ctx, s);
- ChannelPublicKeys {
- funding_pubkey: from_secret(&funding_key),
- revocation_basepoint: from_secret(&revocation_base_key),
- payment_point: from_secret(&payment_key),
- delayed_payment_basepoint: from_secret(&delayed_payment_base_key),
- htlc_basepoint: from_secret(&htlc_base_key),
- }
- }
-
- /// Returns the counterparty's pubkeys.
- ///
- /// 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 [`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 [`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 [`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 [`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 [`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 [`ChannelSigner::provide_channel_parameters`] has not been called before.
- pub fn opt_anchors(&self) -> bool {
- self.get_channel_parameters().opt_anchors.is_some()
- }
- /// Sign the single input of `spend_tx` at index `input_idx`, which spends the output described
- /// by `descriptor`, returning the witness stack for the input.
- ///
- /// Returns an error if the input at `input_idx` does not exist, has a non-empty `script_sig`,
- /// is not spending the outpoint described by [`descriptor.outpoint`],
- /// or if an output descriptor `script_pubkey` does not match the one we can spend.
- ///
- /// [`descriptor.outpoint`]: StaticPaymentOutputDescriptor::outpoint
- pub fn sign_counterparty_payment_input<C: Signing>(&self, spend_tx: &Transaction, input_idx: usize, descriptor: &StaticPaymentOutputDescriptor, secp_ctx: &Secp256k1<C>) -> Result<Vec<Vec<u8>>, ()> {
- // TODO: We really should be taking the SigHashCache as a parameter here instead of
- // spend_tx, but ideally the SigHashCache would expose the transaction's inputs read-only
- // so that we can check them. This requires upstream rust-bitcoin changes (as well as
- // bindings updates to support SigHashCache objects).
- if spend_tx.input.len() <= input_idx { return Err(()); }
- if !spend_tx.input[input_idx].script_sig.is_empty() { return Err(()); }
- if spend_tx.input[input_idx].previous_output != descriptor.outpoint.into_bitcoin_outpoint() { return Err(()); }
-
- let remotepubkey = self.pubkeys().payment_point;
- let witness_script = bitcoin::Address::p2pkh(&::bitcoin::PublicKey{compressed: true, inner: remotepubkey}, Network::Testnet).script_pubkey();
- let sighash = hash_to_message!(&sighash::SighashCache::new(spend_tx).segwit_signature_hash(input_idx, &witness_script, descriptor.output.value, EcdsaSighashType::All).unwrap()[..]);
- let remotesig = sign_with_aux_rand(secp_ctx, &sighash, &self.payment_key, &self);
- let payment_script = bitcoin::Address::p2wpkh(&::bitcoin::PublicKey{compressed: true, inner: remotepubkey}, Network::Bitcoin).unwrap().script_pubkey();
-
- if payment_script != descriptor.output.script_pubkey { return Err(()); }
-
- let mut witness = Vec::with_capacity(2);
- witness.push(remotesig.serialize_der().to_vec());
- witness[0].push(EcdsaSighashType::All as u8);
- witness.push(remotepubkey.serialize().to_vec());
- Ok(witness)
- }
-
- /// Sign the single input of `spend_tx` at index `input_idx` which spends the output
- /// described by `descriptor`, returning the witness stack for the input.
- ///
- /// Returns an error if the input at `input_idx` does not exist, has a non-empty `script_sig`,
- /// is not spending the outpoint described by [`descriptor.outpoint`], does not have a
- /// sequence set to [`descriptor.to_self_delay`], or if an output descriptor
- /// `script_pubkey` does not match the one we can spend.
- ///
- /// [`descriptor.outpoint`]: DelayedPaymentOutputDescriptor::outpoint
- /// [`descriptor.to_self_delay`]: DelayedPaymentOutputDescriptor::to_self_delay
- pub fn sign_dynamic_p2wsh_input<C: Signing>(&self, spend_tx: &Transaction, input_idx: usize, descriptor: &DelayedPaymentOutputDescriptor, secp_ctx: &Secp256k1<C>) -> Result<Vec<Vec<u8>>, ()> {
- // TODO: We really should be taking the SigHashCache as a parameter here instead of
- // spend_tx, but ideally the SigHashCache would expose the transaction's inputs read-only
- // so that we can check them. This requires upstream rust-bitcoin changes (as well as
- // bindings updates to support SigHashCache objects).
- if spend_tx.input.len() <= input_idx { return Err(()); }
- if !spend_tx.input[input_idx].script_sig.is_empty() { return Err(()); }
- if spend_tx.input[input_idx].previous_output != descriptor.outpoint.into_bitcoin_outpoint() { return Err(()); }
- if spend_tx.input[input_idx].sequence.0 != descriptor.to_self_delay as u32 { return Err(()); }
-
- let delayed_payment_key = chan_utils::derive_private_key(&secp_ctx, &descriptor.per_commitment_point, &self.delayed_payment_base_key);
- let delayed_payment_pubkey = PublicKey::from_secret_key(&secp_ctx, &delayed_payment_key);
- let witness_script = chan_utils::get_revokeable_redeemscript(&descriptor.revocation_pubkey, descriptor.to_self_delay, &delayed_payment_pubkey);
- let sighash = hash_to_message!(&sighash::SighashCache::new(spend_tx).segwit_signature_hash(input_idx, &witness_script, descriptor.output.value, EcdsaSighashType::All).unwrap()[..]);
- let local_delayedsig = sign_with_aux_rand(secp_ctx, &sighash, &delayed_payment_key, &self);
- let payment_script = bitcoin::Address::p2wsh(&witness_script, Network::Bitcoin).script_pubkey();
-
- if descriptor.output.script_pubkey != payment_script { return Err(()); }
-
- let mut witness = Vec::with_capacity(3);
- witness.push(local_delayedsig.serialize_der().to_vec());
- witness[0].push(EcdsaSighashType::All as u8);
- witness.push(vec!()); //MINIMALIF
- witness.push(witness_script.clone().into_bytes());
- Ok(witness)
- }
-}
-
-impl EntropySource for InMemorySigner {
- fn get_secure_random_bytes(&self) -> [u8; 32] {
- let index = self.rand_bytes_index.get_increment();
- let mut nonce = [0u8; 16];
- nonce[..8].copy_from_slice(&index.to_be_bytes());
- ChaCha20::get_single_block(&self.rand_bytes_unique_start, &nonce)
- }
-}
-
-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 release_commitment_secret(&self, idx: u64) -> [u8; 32] {
- chan_utils::build_commitment_secret(&self.commitment_seed, idx)
- }
-
- fn validate_holder_commitment(&self, _holder_tx: &HolderCommitmentTransaction, _preimages: Vec<PaymentPreimage>) -> Result<(), ()> {
- Ok(())
- }
-
- fn pubkeys(&self) -> &ChannelPublicKeys { &self.holder_channel_pubkeys }
-
- 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 funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key);
- let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &self.counterparty_pubkeys().funding_pubkey);
-
- let built_tx = trusted_tx.built_transaction();
- let commitment_sig = built_tx.sign_counterparty_commitment(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx);
- let commitment_txid = built_tx.txid;
-
- let mut htlc_sigs = Vec::with_capacity(commitment_tx.htlcs().len());
- for htlc in commitment_tx.htlcs() {
- let channel_parameters = self.get_channel_parameters();
- let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_tx.feerate_per_kw(), self.holder_selected_contest_delay(), htlc, self.opt_anchors(), channel_parameters.opt_non_zero_fee_anchors.is_some(), &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
- let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, self.opt_anchors(), &keys);
- let htlc_sighashtype = if self.opt_anchors() { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };
- let htlc_sighash = hash_to_message!(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, htlc_sighashtype).unwrap()[..]);
- let holder_htlc_key = chan_utils::derive_private_key(&secp_ctx, &keys.per_commitment_point, &self.htlc_base_key);
- htlc_sigs.push(sign(secp_ctx, &htlc_sighash, &holder_htlc_key));
- }
-
- Ok((commitment_sig, htlc_sigs))
- }
-
- fn validate_counterparty_revocation(&self, _idx: u64, _secret: &SecretKey) -> Result<(), ()> {
- Ok(())
- }
-
- fn sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()> {
- 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();
- let sig = trusted_tx.built_transaction().sign_holder_commitment(&self.funding_key, &funding_redeemscript, self.channel_value_satoshis, &self, secp_ctx);
- let channel_parameters = self.get_channel_parameters();
- let htlc_sigs = trusted_tx.get_htlc_sigs(&self.htlc_base_key, &channel_parameters.as_holder_broadcastable(), &self, secp_ctx)?;
- Ok((sig, htlc_sigs))
- }
-
- #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
- fn unsafe_sign_holder_commitment_and_htlcs(&self, commitment_tx: &HolderCommitmentTransaction, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()> {
- 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();
- let sig = trusted_tx.built_transaction().sign_holder_commitment(&self.funding_key, &funding_redeemscript, self.channel_value_satoshis, &self, secp_ctx);
- let channel_parameters = self.get_channel_parameters();
- let htlc_sigs = trusted_tx.get_htlc_sigs(&self.htlc_base_key, &channel_parameters.as_holder_broadcastable(), &self, secp_ctx)?;
- Ok((sig, htlc_sigs))
- }
-
- fn sign_justice_revoked_output(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()> {
- let revocation_key = chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_key, &self.revocation_base_key);
- 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);
- let witness_script = {
- let counterparty_delayedpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().delayed_payment_basepoint);
- chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.holder_selected_contest_delay(), &counterparty_delayedpubkey)
- };
- let mut sighash_parts = sighash::SighashCache::new(justice_tx);
- let sighash = hash_to_message!(&sighash_parts.segwit_signature_hash(input, &witness_script, amount, EcdsaSighashType::All).unwrap()[..]);
- return Ok(sign_with_aux_rand(secp_ctx, &sighash, &revocation_key, &self))
- }
-
- fn sign_justice_revoked_htlc(&self, justice_tx: &Transaction, input: usize, amount: u64, per_commitment_key: &SecretKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()> {
- let revocation_key = chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_key, &self.revocation_base_key);
- 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);
- let witness_script = {
- let counterparty_htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().htlc_basepoint);
- let holder_htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.pubkeys().htlc_basepoint);
- chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, self.opt_anchors(), &counterparty_htlcpubkey, &holder_htlcpubkey, &revocation_pubkey)
- };
- let mut sighash_parts = sighash::SighashCache::new(justice_tx);
- let sighash = hash_to_message!(&sighash_parts.segwit_signature_hash(input, &witness_script, amount, EcdsaSighashType::All).unwrap()[..]);
- return Ok(sign_with_aux_rand(secp_ctx, &sighash, &revocation_key, &self))
- }
-
- #[cfg(anchors)]
- fn sign_holder_htlc_transaction(
- &self, htlc_tx: &Transaction, input: usize, htlc_descriptor: &HTLCDescriptor,
- secp_ctx: &Secp256k1<secp256k1::All>
- ) -> Result<Signature, ()> {
- let per_commitment_point = self.get_per_commitment_point(
- htlc_descriptor.per_commitment_number, &secp_ctx
- );
- let witness_script = htlc_descriptor.witness_script(&per_commitment_point, secp_ctx);
- let sighash = &sighash::SighashCache::new(&*htlc_tx).segwit_signature_hash(
- input, &witness_script, htlc_descriptor.htlc.amount_msat / 1000, EcdsaSighashType::All
- ).map_err(|_| ())?;
- let our_htlc_private_key = chan_utils::derive_private_key(
- &secp_ctx, &per_commitment_point, &self.htlc_base_key
- );
- Ok(sign_with_aux_rand(&secp_ctx, &hash_to_message!(sighash), &our_htlc_private_key, &self))
- }
-
- fn sign_counterparty_htlc_transaction(&self, htlc_tx: &Transaction, input: usize, amount: u64, per_commitment_point: &PublicKey, htlc: &HTLCOutputInCommitment, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()> {
- let htlc_key = chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &self.htlc_base_key);
- let revocation_pubkey = chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &self.pubkeys().revocation_basepoint);
- let counterparty_htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.counterparty_pubkeys().htlc_basepoint);
- let htlcpubkey = chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &self.pubkeys().htlc_basepoint);
- let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, self.opt_anchors(), &counterparty_htlcpubkey, &htlcpubkey, &revocation_pubkey);
- let mut sighash_parts = sighash::SighashCache::new(htlc_tx);
- let sighash = hash_to_message!(&sighash_parts.segwit_signature_hash(input, &witness_script, amount, EcdsaSighashType::All).unwrap()[..]);
- Ok(sign_with_aux_rand(secp_ctx, &sighash, &htlc_key, &self))
- }
-
- fn sign_closing_transaction(&self, closing_tx: &ClosingTransaction, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()> {
- let funding_pubkey = PublicKey::from_secret_key(secp_ctx, &self.funding_key);
- let channel_funding_redeemscript = make_funding_redeemscript(&funding_pubkey, &self.counterparty_pubkeys().funding_pubkey);
- Ok(closing_tx.trust().sign(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx))
- }
-
- fn sign_holder_anchor_input(
- &self, anchor_tx: &Transaction, input: usize, secp_ctx: &Secp256k1<secp256k1::All>,
- ) -> Result<Signature, ()> {
- let witness_script = chan_utils::get_anchor_redeemscript(&self.holder_channel_pubkeys.funding_pubkey);
- let sighash = sighash::SighashCache::new(&*anchor_tx).segwit_signature_hash(
- input, &witness_script, ANCHOR_OUTPUT_VALUE_SATOSHI, EcdsaSighashType::All,
- ).unwrap();
- Ok(sign_with_aux_rand(secp_ctx, &hash_to_message!(&sighash[..]), &self.funding_key, &self))
- }
-
- fn sign_channel_announcement_with_funding_key(
- &self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>
- ) -> Result<Signature, ()> {
- let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
- Ok(secp_ctx.sign_ecdsa(&msghash, &self.funding_key))
- }
-}
-
-const SERIALIZATION_VERSION: u8 = 1;
-
-const MIN_SERIALIZATION_VERSION: u8 = 1;
-
-impl WriteableEcdsaChannelSigner for InMemorySigner {}
-
-impl Writeable for InMemorySigner {
- fn write<W: Writer>(&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)?;
- self.delayed_payment_base_key.write(writer)?;
- self.htlc_base_key.write(writer)?;
- self.commitment_seed.write(writer)?;
- self.channel_parameters.write(writer)?;
- self.channel_value_satoshis.write(writer)?;
- self.channel_keys_id.write(writer)?;
-
- write_tlv_fields!(writer, {});
-
- Ok(())
- }
-}
-
-impl<ES: Deref> ReadableArgs<ES> for InMemorySigner where ES::Target: EntropySource {
- fn read<R: io::Read>(reader: &mut R, entropy_source: ES) -> Result<Self, DecodeError> {
- 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)?;
- let delayed_payment_base_key = Readable::read(reader)?;
- let htlc_base_key = Readable::read(reader)?;
- let commitment_seed = Readable::read(reader)?;
- let counterparty_channel_data = Readable::read(reader)?;
- let channel_value_satoshis = Readable::read(reader)?;
- let secp_ctx = Secp256k1::signing_only();
- let holder_channel_pubkeys =
- 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)?;
-
- read_tlv_fields!(reader, {});
-
- Ok(InMemorySigner {
- funding_key,
- revocation_base_key,
- payment_key,
- delayed_payment_base_key,
- htlc_base_key,
- commitment_seed,
- channel_value_satoshis,
- holder_channel_pubkeys,
- channel_parameters: counterparty_channel_data,
- channel_keys_id: keys_id,
- rand_bytes_unique_start: entropy_source.get_secure_random_bytes(),
- rand_bytes_index: AtomicCounter::new(),
- })
- }
-}
-
-/// Simple implementation of [`EntropySource`], [`NodeSigner`], and [`SignerProvider`] that takes a
-/// 32-byte seed for use as a BIP 32 extended key and derives keys from that.
-///
-/// Your `node_id` is seed/0'.
-/// Unilateral closes may use seed/1'.
-/// Cooperative closes may use seed/2'.
-/// The two close keys may be needed to claim on-chain funds!
-///
-/// This struct cannot be used for nodes that wish to support receiving phantom payments;
-/// [`PhantomKeysManager`] must be used instead.
-///
-/// Note that switching between this struct and [`PhantomKeysManager`] will invalidate any
-/// previously issued invoices and attempts to pay previous invoices will fail.
-pub struct KeysManager {
- secp_ctx: Secp256k1<secp256k1::All>,
- node_secret: SecretKey,
- node_id: PublicKey,
- inbound_payment_key: KeyMaterial,
- destination_script: Script,
- shutdown_pubkey: PublicKey,
- channel_master_key: ExtendedPrivKey,
- channel_child_index: AtomicUsize,
-
- rand_bytes_unique_start: [u8; 32],
- rand_bytes_index: AtomicCounter,
-
- seed: [u8; 32],
- starting_time_secs: u64,
- starting_time_nanos: u32,
-}
-
-impl KeysManager {
- /// Constructs a [`KeysManager`] from a 32-byte seed. If the seed is in some way biased (e.g.,
- /// your CSRNG is busted) this may panic (but more importantly, you will possibly lose funds).
- /// `starting_time` isn't strictly required to actually be a time, but it must absolutely,
- /// without a doubt, be unique to this instance. ie if you start multiple times with the same
- /// `seed`, `starting_time` must be unique to each run. Thus, the easiest way to achieve this
- /// is to simply use the current time (with very high precision).
- ///
- /// The `seed` MUST be backed up safely prior to use so that the keys can be re-created, however,
- /// obviously, `starting_time` should be unique every time you reload the library - it is only
- /// used to generate new ephemeral key data (which will be stored by the individual channel if
- /// necessary).
- ///
- /// Note that the seed is required to recover certain on-chain funds independent of
- /// [`ChannelMonitor`] data, though a current copy of [`ChannelMonitor`] data is also required
- /// for any channel, and some on-chain during-closing funds.
- ///
- /// [`ChannelMonitor`]: crate::chain::channelmonitor::ChannelMonitor
- pub fn new(seed: &[u8; 32], starting_time_secs: u64, starting_time_nanos: u32) -> Self {
- 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) => {
- let node_secret = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(0).unwrap()).expect("Your RNG is busted").private_key;
- let node_id = PublicKey::from_secret_key(&secp_ctx, &node_secret);
- let destination_script = match master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(1).unwrap()) {
- Ok(destination_key) => {
- let wpubkey_hash = WPubkeyHash::hash(&ExtendedPubKey::from_priv(&secp_ctx, &destination_key).to_pub().to_bytes());
- Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
- .push_slice(&wpubkey_hash.into_inner())
- .into_script()
- },
- Err(_) => panic!("Your RNG is busted"),
- };
- let shutdown_pubkey = match master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(2).unwrap()) {
- Ok(shutdown_key) => ExtendedPubKey::from_priv(&secp_ctx, &shutdown_key).public_key,
- Err(_) => panic!("Your RNG is busted"),
- };
- let channel_master_key = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(3).unwrap()).expect("Your RNG is busted");
- let inbound_payment_key: SecretKey = master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(5).unwrap()).expect("Your RNG is busted").private_key;
- let mut inbound_pmt_key_bytes = [0; 32];
- inbound_pmt_key_bytes.copy_from_slice(&inbound_payment_key[..]);
-
- let mut rand_bytes_engine = Sha256::engine();
- rand_bytes_engine.input(&starting_time_secs.to_be_bytes());
- rand_bytes_engine.input(&starting_time_nanos.to_be_bytes());
- rand_bytes_engine.input(seed);
- rand_bytes_engine.input(b"LDK PRNG Seed");
- let rand_bytes_unique_start = Sha256::from_engine(rand_bytes_engine).into_inner();
-
- let mut res = KeysManager {
- secp_ctx,
- node_secret,
- node_id,
- inbound_payment_key: KeyMaterial(inbound_pmt_key_bytes),
-
- destination_script,
- shutdown_pubkey,
-
- channel_master_key,
- channel_child_index: AtomicUsize::new(0),
-
- rand_bytes_unique_start,
- rand_bytes_index: AtomicCounter::new(),
-
- 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"),
- }
- }
-
- /// Gets the "node_id" secret key used to sign gossip announcements, decode onion data, etc.
- pub fn get_node_secret_key(&self) -> SecretKey {
- self.node_secret
- }
-
- /// 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();
- unique_start.input(params);
- unique_start.input(&self.seed);
-
- // We only seriously intend to rely on the channel_master_key for true secure
- // entropy, everything else just ensures uniqueness. We rely on the unique_start (ie
- // starting_time provided in the constructor) to be unique.
- let child_privkey = self.channel_master_key.ckd_priv(&self.secp_ctx,
- ChildNumber::from_hardened_idx((chan_id as u32) % (1 << 31)).expect("key space exhausted")
- ).expect("Your RNG is busted");
- unique_start.input(&child_privkey.private_key[..]);
-
- let seed = Sha256::from_engine(unique_start).into_inner();
-
- let commitment_seed = {
- let mut sha = Sha256::engine();
- sha.input(&seed);
- sha.input(&b"commitment seed"[..]);
- Sha256::from_engine(sha).into_inner()
- };
- macro_rules! key_step {
- ($info: expr, $prev_key: expr) => {{
- let mut sha = Sha256::engine();
- sha.input(&seed);
- sha.input(&$prev_key[..]);
- sha.input(&$info[..]);
- SecretKey::from_slice(&Sha256::from_engine(sha).into_inner()).expect("SHA-256 is busted")
- }}
- }
- let funding_key = key_step!(b"funding key", commitment_seed);
- let revocation_base_key = key_step!(b"revocation base key", funding_key);
- let payment_key = key_step!(b"payment key", revocation_base_key);
- 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);
- let prng_seed = self.get_secure_random_bytes();
-
- InMemorySigner::new(
- &self.secp_ctx,
- funding_key,
- revocation_base_key,
- payment_key,
- delayed_payment_base_key,
- htlc_base_key,
- commitment_seed,
- channel_value_satoshis,
- params.clone(),
- prng_seed,
- )
- }
-
- /// Creates a [`Transaction`] which spends the given descriptors to the given outputs, plus an
- /// output to the given change destination (if sufficient change value remains). The
- /// transaction will have a feerate, at least, of the given value.
- ///
- /// Returns `Err(())` if the output value is greater than the input value minus required fee,
- /// if a descriptor was duplicated, or if an output descriptor `script_pubkey`
- /// does not match the one we can spend.
- ///
- /// 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 [`InMemorySigner`] created by this [`KeysManager`].
- pub fn spend_spendable_outputs<C: Signing>(&self, descriptors: &[&SpendableOutputDescriptor], outputs: Vec<TxOut>, change_destination_script: Script, feerate_sat_per_1000_weight: u32, secp_ctx: &Secp256k1<C>) -> Result<Transaction, ()> {
- let mut input = Vec::new();
- let mut input_value = 0;
- let mut witness_weight = 0;
- let mut output_set = HashSet::with_capacity(descriptors.len());
- for outp in descriptors {
- match outp {
- SpendableOutputDescriptor::StaticPaymentOutput(descriptor) => {
- input.push(TxIn {
- previous_output: descriptor.outpoint.into_bitcoin_outpoint(),
- script_sig: Script::new(),
- sequence: Sequence::ZERO,
- witness: Witness::new(),
- });
- witness_weight += StaticPaymentOutputDescriptor::MAX_WITNESS_LENGTH;
- #[cfg(feature = "grind_signatures")]
- { witness_weight -= 1; } // Guarantees a low R signature
- input_value += descriptor.output.value;
- if !output_set.insert(descriptor.outpoint) { return Err(()); }
- },
- SpendableOutputDescriptor::DelayedPaymentOutput(descriptor) => {
- input.push(TxIn {
- previous_output: descriptor.outpoint.into_bitcoin_outpoint(),
- script_sig: Script::new(),
- sequence: Sequence(descriptor.to_self_delay as u32),
- witness: Witness::new(),
- });
- witness_weight += DelayedPaymentOutputDescriptor::MAX_WITNESS_LENGTH;
- #[cfg(feature = "grind_signatures")]
- { witness_weight -= 1; } // Guarantees a low R signature
- input_value += descriptor.output.value;
- if !output_set.insert(descriptor.outpoint) { return Err(()); }
- },
- SpendableOutputDescriptor::StaticOutput { ref outpoint, ref output } => {
- input.push(TxIn {
- previous_output: outpoint.into_bitcoin_outpoint(),
- script_sig: Script::new(),
- sequence: Sequence::ZERO,
- witness: Witness::new(),
- });
- witness_weight += 1 + 73 + 34;
- #[cfg(feature = "grind_signatures")]
- { witness_weight -= 1; } // Guarantees a low R signature
- input_value += output.value;
- if !output_set.insert(*outpoint) { return Err(()); }
- }
- }
- if input_value > MAX_VALUE_MSAT / 1000 { return Err(()); }
- }
- let mut spend_tx = Transaction {
- version: 2,
- lock_time: PackedLockTime(0),
- input,
- output: outputs,
- };
- let expected_max_weight =
- 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<(InMemorySigner, [u8; 32])> = None;
- let mut input_idx = 0;
- for outp in descriptors {
- match outp {
- SpendableOutputDescriptor::StaticPaymentOutput(descriptor) => {
- if keys_cache.is_none() || keys_cache.as_ref().unwrap().1 != descriptor.channel_keys_id {
- keys_cache = Some((
- self.derive_channel_keys(descriptor.channel_value_satoshis, &descriptor.channel_keys_id),
- descriptor.channel_keys_id));
- }
- spend_tx.input[input_idx].witness = Witness::from_vec(keys_cache.as_ref().unwrap().0.sign_counterparty_payment_input(&spend_tx, input_idx, &descriptor, &secp_ctx)?);
- },
- SpendableOutputDescriptor::DelayedPaymentOutput(descriptor) => {
- if keys_cache.is_none() || keys_cache.as_ref().unwrap().1 != descriptor.channel_keys_id {
- keys_cache = Some((
- self.derive_channel_keys(descriptor.channel_value_satoshis, &descriptor.channel_keys_id),
- descriptor.channel_keys_id));
- }
- spend_tx.input[input_idx].witness = Witness::from_vec(keys_cache.as_ref().unwrap().0.sign_dynamic_p2wsh_input(&spend_tx, input_idx, &descriptor, &secp_ctx)?);
- },
- SpendableOutputDescriptor::StaticOutput { ref output, .. } => {
- let derivation_idx = if output.script_pubkey == self.destination_script {
- 1
- } else {
- 2
- };
- let secret = {
- // Note that when we aren't serializing the key, network doesn't matter
- match ExtendedPrivKey::new_master(Network::Testnet, &self.seed) {
- Ok(master_key) => {
- match master_key.ckd_priv(&secp_ctx, ChildNumber::from_hardened_idx(derivation_idx).expect("key space exhausted")) {
- Ok(key) => key,
- Err(_) => panic!("Your RNG is busted"),
- }
- }
- Err(_) => panic!("Your rng is busted"),
- }
- };
- let pubkey = ExtendedPubKey::from_priv(&secp_ctx, &secret).to_pub();
- if derivation_idx == 2 {
- assert_eq!(pubkey.inner, self.shutdown_pubkey);
- }
- let witness_script = bitcoin::Address::p2pkh(&pubkey, Network::Testnet).script_pubkey();
- let payment_script = bitcoin::Address::p2wpkh(&pubkey, Network::Testnet).expect("uncompressed key found").script_pubkey();
-
- if payment_script != output.script_pubkey { return Err(()); };
-
- let sighash = hash_to_message!(&sighash::SighashCache::new(&spend_tx).segwit_signature_hash(input_idx, &witness_script, output.value, EcdsaSighashType::All).unwrap()[..]);
- let sig = sign_with_aux_rand(secp_ctx, &sighash, &secret.private_key, &self);
- let mut sig_ser = sig.serialize_der().to_vec();
- sig_ser.push(EcdsaSighashType::All as u8);
- spend_tx.input[input_idx].witness.push(sig_ser);
- spend_tx.input[input_idx].witness.push(pubkey.inner.serialize().to_vec());
- },
- }
- input_idx += 1;
- }
-
- debug_assert!(expected_max_weight >= spend_tx.weight());
- // Note that witnesses with a signature vary somewhat in size, so allow
- // `expected_max_weight` to overshoot by up to 3 bytes per input.
- debug_assert!(expected_max_weight <= spend_tx.weight() + descriptors.len() * 3);
-
- Ok(spend_tx)
- }
-}
-
-impl EntropySource for KeysManager {
- fn get_secure_random_bytes(&self) -> [u8; 32] {
- let index = self.rand_bytes_index.get_increment();
- let mut nonce = [0u8; 16];
- nonce[..8].copy_from_slice(&index.to_be_bytes());
- ChaCha20::get_single_block(&self.rand_bytes_unique_start, &nonce)
- }
-}
-
-impl NodeSigner for KeysManager {
- fn get_node_id(&self, recipient: Recipient) -> Result<PublicKey, ()> {
- match recipient {
- Recipient::Node => Ok(self.node_id.clone()),
- Recipient::PhantomNode => Err(())
- }
- }
-
- fn ecdh(&self, recipient: Recipient, other_key: &PublicKey, tweak: Option<&Scalar>) -> Result<SharedSecret, ()> {
- let mut node_secret = match recipient {
- Recipient::Node => Ok(self.node_secret.clone()),
- Recipient::PhantomNode => Err(())
- }?;
- if let Some(tweak) = tweak {
- node_secret = node_secret.mul_tweak(tweak).map_err(|_| ())?;
- }
- Ok(SharedSecret::new(other_key, &node_secret))
- }
-
- fn get_inbound_payment_key_material(&self) -> KeyMaterial {
- self.inbound_payment_key.clone()
- }
-
- fn sign_invoice(&self, hrp_bytes: &[u8], invoice_data: &[u5], recipient: Recipient) -> Result<RecoverableSignature, ()> {
- let preimage = construct_invoice_preimage(&hrp_bytes, &invoice_data);
- let secret = match recipient {
- Recipient::Node => Ok(&self.node_secret),
- Recipient::PhantomNode => Err(())
- }?;
- Ok(self.secp_ctx.sign_ecdsa_recoverable(&hash_to_message!(&Sha256::hash(&preimage)), secret))
- }
-
- fn sign_gossip_message(&self, msg: UnsignedGossipMessage) -> Result<Signature, ()> {
- let msg_hash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
- Ok(self.secp_ctx.sign_ecdsa(&msg_hash, &self.node_secret))
- }
-}
-
-impl SignerProvider for KeysManager {
- type Signer = InMemorySigner;
-
- fn generate_channel_keys_id(&self, _inbound: bool, _channel_value_satoshis: u64, user_channel_id: u128) -> [u8; 32] {
- let child_idx = self.channel_child_index.fetch_add(1, Ordering::AcqRel);
- // `child_idx` is the only thing guaranteed to make each channel unique without a restart
- // (though `user_channel_id` should help, depending on user behavior). If it manages to
- // roll over, we may generate duplicate keys for two different channels, which could result
- // in loss of funds. Because we only support 32-bit+ systems, assert that our `AtomicUsize`
- // doesn't reach `u32::MAX`.
- assert!(child_idx < core::u32::MAX as usize, "2^32 channels opened without restart");
- let mut id = [0; 32];
- id[0..4].copy_from_slice(&(child_idx as u32).to_be_bytes());
- id[4..8].copy_from_slice(&self.starting_time_nanos.to_be_bytes());
- id[8..16].copy_from_slice(&self.starting_time_secs.to_be_bytes());
- id[16..32].copy_from_slice(&user_channel_id.to_be_bytes());
- id
- }
-
- fn derive_channel_signer(&self, channel_value_satoshis: u64, channel_keys_id: [u8; 32]) -> Self::Signer {
- self.derive_channel_keys(channel_value_satoshis, &channel_keys_id)
- }
-
- fn read_chan_signer(&self, reader: &[u8]) -> Result<Self::Signer, DecodeError> {
- InMemorySigner::read(&mut io::Cursor::new(reader), self)
- }
-
- fn get_destination_script(&self) -> Result<Script, ()> {
- Ok(self.destination_script.clone())
- }
-
- fn get_shutdown_scriptpubkey(&self) -> Result<ShutdownScript, ()> {
- Ok(ShutdownScript::new_p2wpkh_from_pubkey(self.shutdown_pubkey.clone()))
- }
-}
-
-/// Similar to [`KeysManager`], but allows the node using this struct to receive phantom node
-/// payments.
-///
-/// A phantom node payment is a payment made to a phantom invoice, which is an invoice that can be
-/// paid to one of multiple nodes. This works because we encode the invoice route hints such that
-/// LDK will recognize an incoming payment as destined for a phantom node, and collect the payment
-/// itself without ever needing to forward to this fake node.
-///
-/// Phantom node payments are useful for load balancing between multiple LDK nodes. They also
-/// provide some fault tolerance, because payers will automatically retry paying other provided
-/// nodes in the case that one node goes down.
-///
-/// Note that multi-path payments are not supported in phantom invoices for security reasons.
-// In the hypothetical case that we did support MPP phantom payments, there would be no way for
-// nodes to know when the full payment has been received (and the preimage can be released) without
-// significantly compromising on our safety guarantees. I.e., if we expose the ability for the user
-// to tell LDK when the preimage can be released, we open ourselves to attacks where the preimage
-// is released too early.
-//
-/// Switching between this struct and [`KeysManager`] will invalidate any previously issued
-/// invoices and attempts to pay previous invoices will fail.
-pub struct PhantomKeysManager {
- inner: KeysManager,
- inbound_payment_key: KeyMaterial,
- phantom_secret: SecretKey,
- phantom_node_id: PublicKey,
-}
-
-impl EntropySource for PhantomKeysManager {
- fn get_secure_random_bytes(&self) -> [u8; 32] {
- self.inner.get_secure_random_bytes()
- }
-}
-
-impl NodeSigner for PhantomKeysManager {
- fn get_node_id(&self, recipient: Recipient) -> Result<PublicKey, ()> {
- match recipient {
- Recipient::Node => self.inner.get_node_id(Recipient::Node),
- Recipient::PhantomNode => Ok(self.phantom_node_id.clone()),
- }
- }
-
- fn ecdh(&self, recipient: Recipient, other_key: &PublicKey, tweak: Option<&Scalar>) -> Result<SharedSecret, ()> {
- let mut node_secret = match recipient {
- Recipient::Node => self.inner.node_secret.clone(),
- Recipient::PhantomNode => self.phantom_secret.clone(),
- };
- if let Some(tweak) = tweak {
- node_secret = node_secret.mul_tweak(tweak).map_err(|_| ())?;
- }
- Ok(SharedSecret::new(other_key, &node_secret))
- }
-
- fn get_inbound_payment_key_material(&self) -> KeyMaterial {
- self.inbound_payment_key.clone()
- }
-
- fn sign_invoice(&self, hrp_bytes: &[u8], invoice_data: &[u5], recipient: Recipient) -> Result<RecoverableSignature, ()> {
- let preimage = construct_invoice_preimage(&hrp_bytes, &invoice_data);
- let secret = match recipient {
- Recipient::Node => &self.inner.node_secret,
- Recipient::PhantomNode => &self.phantom_secret,
- };
- Ok(self.inner.secp_ctx.sign_ecdsa_recoverable(&hash_to_message!(&Sha256::hash(&preimage)), secret))
- }
-
- fn sign_gossip_message(&self, msg: UnsignedGossipMessage) -> Result<Signature, ()> {
- self.inner.sign_gossip_message(msg)
- }
-}
-
-impl SignerProvider for PhantomKeysManager {
- type Signer = InMemorySigner;
-
- fn generate_channel_keys_id(&self, inbound: bool, channel_value_satoshis: u64, user_channel_id: u128) -> [u8; 32] {
- self.inner.generate_channel_keys_id(inbound, channel_value_satoshis, user_channel_id)
- }
-
- fn derive_channel_signer(&self, channel_value_satoshis: u64, channel_keys_id: [u8; 32]) -> Self::Signer {
- self.inner.derive_channel_signer(channel_value_satoshis, channel_keys_id)
- }
-
- fn read_chan_signer(&self, reader: &[u8]) -> Result<Self::Signer, DecodeError> {
- self.inner.read_chan_signer(reader)
- }
-
- fn get_destination_script(&self) -> Result<Script, ()> {
- self.inner.get_destination_script()
- }
-
- fn get_shutdown_scriptpubkey(&self) -> Result<ShutdownScript, ()> {
- self.inner.get_shutdown_scriptpubkey()
- }
-}
-
-impl PhantomKeysManager {
- /// Constructs a [`PhantomKeysManager`] given a 32-byte seed and an additional `cross_node_seed`
- /// that is shared across all nodes that intend to participate in [phantom node payments]
- /// together.
- ///
- /// See [`KeysManager::new`] for more information on `seed`, `starting_time_secs`, and
- /// `starting_time_nanos`.
- ///
- /// `cross_node_seed` must be the same across all phantom payment-receiving nodes and also the
- /// same across restarts, or else inbound payments may fail.
- ///
- /// [phantom node payments]: PhantomKeysManager
- pub fn new(seed: &[u8; 32], starting_time_secs: u64, starting_time_nanos: u32, cross_node_seed: &[u8; 32]) -> Self {
- let inner = KeysManager::new(seed, starting_time_secs, starting_time_nanos);
- let (inbound_key, phantom_key) = hkdf_extract_expand_twice(b"LDK Inbound and Phantom Payment Key Expansion", cross_node_seed);
- let phantom_secret = SecretKey::from_slice(&phantom_key).unwrap();
- let phantom_node_id = PublicKey::from_secret_key(&inner.secp_ctx, &phantom_secret);
- Self {
- inner,
- inbound_payment_key: KeyMaterial(inbound_key),
- phantom_secret,
- phantom_node_id,
- }
- }
-
- /// See [`KeysManager::spend_spendable_outputs`] for documentation on this method.
- pub fn spend_spendable_outputs<C: Signing>(&self, descriptors: &[&SpendableOutputDescriptor], outputs: Vec<TxOut>, change_destination_script: Script, feerate_sat_per_1000_weight: u32, secp_ctx: &Secp256k1<C>) -> Result<Transaction, ()> {
- self.inner.spend_spendable_outputs(descriptors, outputs, change_destination_script, feerate_sat_per_1000_weight, secp_ctx)
- }
-
- /// See [`KeysManager::derive_channel_keys`] for documentation on this method.
- pub fn derive_channel_keys(&self, channel_value_satoshis: u64, params: &[u8; 32]) -> InMemorySigner {
- self.inner.derive_channel_keys(channel_value_satoshis, params)
- }
-
- /// Gets the "node_id" secret key used to sign gossip announcements, decode onion data, etc.
- pub fn get_node_secret_key(&self) -> SecretKey {
- self.inner.get_node_secret_key()
- }
-
- /// Gets the "node_id" secret key of the phantom node used to sign invoices, decode the
- /// last-hop onion data, etc.
- pub fn get_phantom_node_secret_key(&self) -> SecretKey {
- self.phantom_secret
- }
-}
-
-// Ensure that EcdsaChannelSigner can have a vtable
-#[test]
-pub fn dyn_sign() {
- let _signer: Box<dyn EcdsaChannelSigner>;
-}
-
-#[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
-mod benches {
- use std::sync::{Arc, mpsc};
- use std::sync::mpsc::TryRecvError;
- use std::thread;
- use std::time::Duration;
- use bitcoin::blockdata::constants::genesis_block;
- use bitcoin::Network;
- use crate::chain::keysinterface::{EntropySource, KeysManager};
-
- use test::Bencher;
-
- #[bench]
- fn bench_get_secure_random_bytes(bench: &mut Bencher) {
- let seed = [0u8; 32];
- let now = Duration::from_secs(genesis_block(Network::Testnet).header.time as u64);
- let keys_manager = Arc::new(KeysManager::new(&seed, now.as_secs(), now.subsec_micros()));
-
- let mut handles = Vec::new();
- let mut stops = Vec::new();
- for _ in 1..5 {
- let keys_manager_clone = Arc::clone(&keys_manager);
- let (stop_sender, stop_receiver) = mpsc::channel();
- let handle = thread::spawn(move || {
- loop {
- keys_manager_clone.get_secure_random_bytes();
- match stop_receiver.try_recv() {
- Ok(_) | Err(TryRecvError::Disconnected) => {
- println!("Terminating.");
- break;
- }
- Err(TryRecvError::Empty) => {}
- }
- }
- });
- handles.push(handle);
- stops.push(stop_sender);
- }
-
- bench.iter(|| {
- for _ in 1..100 {
- keys_manager.get_secure_random_bytes();
- }
- });
-
- for stop in stops {
- let _ = stop.send(());
- }
- for handle in handles {
- handle.join().unwrap();
- }
- }
-
-}
projects / rust-lightning / blobdiff