Remove unnecessary mut from reference
[rust-lightning] / lightning / src / chain / keysinterface.rs
index a7965d4f3419a15c4c97460fca7cc77951521800..dffe060d91bb71a5f33e8c023de6cac94fb9826d 100644 (file)
@@ -18,6 +18,7 @@ use bitcoin::network::constants::Network;
 use bitcoin::util::bip32::{ExtendedPrivKey, ExtendedPubKey, ChildNumber};
 use bitcoin::util::bip143;
 
+use bitcoin::bech32::u5;
 use bitcoin::hashes::{Hash, HashEngine};
 use bitcoin::hashes::sha256::HashEngine as Sha256State;
 use bitcoin::hashes::sha256::Hash as Sha256;
@@ -30,10 +31,10 @@ use bitcoin::secp256k1::recovery::RecoverableSignature;
 use bitcoin::secp256k1;
 
 use util::{byte_utils, transaction_utils};
-use util::ser::{Writeable, Writer, Readable};
+use util::ser::{Writeable, Writer, Readable, ReadableArgs};
 
 use chain::transaction::OutPoint;
-use ln::chan_utils;
+use ln::{chan_utils, PaymentPreimage};
 use ln::chan_utils::{HTLCOutputInCommitment, make_funding_redeemscript, ChannelPublicKeys, HolderCommitmentTransaction, ChannelTransactionParameters, CommitmentTransaction, ClosingTransaction};
 use ln::msgs::UnsignedChannelAnnouncement;
 use ln::script::ShutdownScript;
@@ -42,6 +43,7 @@ use prelude::*;
 use core::sync::atomic::{AtomicUsize, Ordering};
 use io::{self, Error};
 use ln::msgs::{DecodeError, MAX_VALUE_MSAT};
+use 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.
@@ -224,7 +226,14 @@ pub trait BaseSign {
        /// 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.
-       fn validate_holder_commitment(&self, holder_tx: &HolderCommitmentTransaction) -> Result<(), ()>;
+       ///
+       /// 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: 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<(), ()>;
        /// Gets the holder's channel public keys and basepoints
        fn pubkeys(&self) -> &ChannelPublicKeys;
        /// Gets an arbitrary identifier describing the set of keys which are provided back to you in
@@ -238,9 +247,16 @@ pub trait BaseSign {
        ///
        /// 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: 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, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()>;
+       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
@@ -330,13 +346,17 @@ pub trait BaseSign {
        /// chosen to forgo their output as dust.
        fn sign_closing_transaction(&self, closing_tx: &ClosingTransaction, 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.
+       /// Signs a channel announcement message with our funding key and our node secret key (aka
+       /// node_id or network_key), proving it comes from one of the channel participants.
+       ///
+       /// The first returned signature should be from our node secret key, the second from our
+       /// funding key.
        ///
        /// Note that if this fails or is rejected, the channel will not be publicly announced and
        /// our counterparty may (though likely will not) close the channel on us for violating the
        /// protocol.
-       fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()>;
+       fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>)
+               -> Result<(Signature, Signature), ()>;
 
        /// Set the counterparty static channel data, including basepoints,
        /// counterparty_selected/holder_selected_contest_delay and funding outpoint.
@@ -398,11 +418,12 @@ pub trait KeysInterface {
        /// you've read all of the provided bytes to ensure no corruption occurred.
        fn read_chan_signer(&self, reader: &[u8]) -> Result<Self::Signer, DecodeError>;
 
-       /// Sign an invoice's preimage (note that this is the preimage of the invoice, not the HTLC's
-       /// preimage). By parameterizing by the preimage instead of the hash, we allow implementors of
+       /// 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.
-       fn sign_invoice(&self, invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()>;
+       /// The hrp is ascii bytes, while the invoice data is base32.
+       fn sign_invoice(&self, hrp_bytes: &[u8], invoice_data: &[u5]) -> Result<RecoverableSignature, ()>;
 
        /// Get secret key material as bytes for use in encrypting and decrypting inbound payment data.
        ///
@@ -430,6 +451,8 @@ pub struct InMemorySigner {
        pub commitment_seed: [u8; 32],
        /// Holder public keys and basepoints
        pub(crate) holder_channel_pubkeys: ChannelPublicKeys,
+       /// Private key of our node secret, used for signing channel announcements
+       node_secret: SecretKey,
        /// Counterparty public keys and counterparty/holder selected_contest_delay, populated on channel acceptance
        channel_parameters: Option<ChannelTransactionParameters>,
        /// The total value of this channel
@@ -442,6 +465,7 @@ impl InMemorySigner {
        /// Create a new InMemorySigner
        pub fn new<C: Signing>(
                secp_ctx: &Secp256k1<C>,
+               node_secret: SecretKey,
                funding_key: SecretKey,
                revocation_base_key: SecretKey,
                payment_key: SecretKey,
@@ -461,6 +485,7 @@ impl InMemorySigner {
                        delayed_payment_base_key,
                        htlc_base_key,
                        commitment_seed,
+                       node_secret,
                        channel_value_satoshis,
                        holder_channel_pubkeys,
                        channel_parameters: None,
@@ -526,7 +551,8 @@ impl InMemorySigner {
        /// described by descriptor, returning the witness stack for the input.
        ///
        /// Returns an Err if the input at input_idx does not exist, has a non-empty script_sig,
-       /// or is not spending the outpoint described by `descriptor.outpoint`.
+       /// is not spending the outpoint described by `descriptor.outpoint`,
+       /// or if an output descriptor script_pubkey does not match the one we can spend.
        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
@@ -540,6 +566,9 @@ impl InMemorySigner {
                let witness_script = bitcoin::Address::p2pkh(&::bitcoin::PublicKey{compressed: true, key: remotepubkey}, Network::Testnet).script_pubkey();
                let sighash = hash_to_message!(&bip143::SigHashCache::new(spend_tx).signature_hash(input_idx, &witness_script, descriptor.output.value, SigHashType::All)[..]);
                let remotesig = secp_ctx.sign(&sighash, &self.payment_key);
+               let payment_script = bitcoin::Address::p2wpkh(&::bitcoin::PublicKey{compressed: true, key: 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());
@@ -552,8 +581,9 @@ impl InMemorySigner {
        /// described by descriptor, returning the witness stack for the input.
        ///
        /// Returns an Err 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 does not have a
-       /// sequence set to `descriptor.to_self_delay`.
+       /// 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.
        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
@@ -570,6 +600,9 @@ impl InMemorySigner {
                let witness_script = chan_utils::get_revokeable_redeemscript(&descriptor.revocation_pubkey, descriptor.to_self_delay, &delayed_payment_pubkey);
                let sighash = hash_to_message!(&bip143::SigHashCache::new(spend_tx).signature_hash(input_idx, &witness_script, descriptor.output.value, SigHashType::All)[..]);
                let local_delayedsig = secp_ctx.sign(&sighash, &delayed_payment_key);
+               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());
@@ -590,14 +623,14 @@ impl BaseSign for InMemorySigner {
                chan_utils::build_commitment_secret(&self.commitment_seed, idx)
        }
 
-       fn validate_holder_commitment(&self, _holder_tx: &HolderCommitmentTransaction) -> Result<(), ()> {
+       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 sign_counterparty_commitment(&self, commitment_tx: &CommitmentTransaction, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<(Signature, Vec<Signature>), ()> {
+       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();
 
@@ -695,9 +728,10 @@ impl BaseSign for InMemorySigner {
                Ok(closing_tx.trust().sign(&self.funding_key, &channel_funding_redeemscript, self.channel_value_satoshis, secp_ctx))
        }
 
-       fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>) -> Result<Signature, ()> {
+       fn sign_channel_announcement(&self, msg: &UnsignedChannelAnnouncement, secp_ctx: &Secp256k1<secp256k1::All>)
+       -> Result<(Signature, Signature), ()> {
                let msghash = hash_to_message!(&Sha256dHash::hash(&msg.encode()[..])[..]);
-               Ok(secp_ctx.sign(&msghash, &self.funding_key))
+               Ok((secp_ctx.sign(&msghash, &self.node_secret), secp_ctx.sign(&msghash, &self.funding_key)))
        }
 
        fn ready_channel(&mut self, channel_parameters: &ChannelTransactionParameters) {
@@ -732,8 +766,8 @@ impl Writeable for InMemorySigner {
        }
 }
 
-impl Readable for InMemorySigner {
-       fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+impl ReadableArgs<SecretKey> for InMemorySigner {
+       fn read<R: io::Read>(reader: &mut R, node_secret: SecretKey) -> Result<Self, DecodeError> {
                let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
 
                let funding_key = Readable::read(reader)?;
@@ -759,6 +793,7 @@ impl Readable for InMemorySigner {
                        payment_key,
                        delayed_payment_base_key,
                        htlc_base_key,
+                       node_secret,
                        commitment_seed,
                        channel_value_satoshis,
                        holder_channel_pubkeys,
@@ -912,6 +947,7 @@ impl KeysManager {
 
                InMemorySigner::new(
                        &self.secp_ctx,
+                       self.node_secret,
                        funding_key,
                        revocation_base_key,
                        payment_key,
@@ -927,8 +963,9 @@ impl KeysManager {
        /// 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 or
-       /// if a descriptor was duplicated.
+       /// 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.
        ///
@@ -996,7 +1033,7 @@ impl KeysManager {
                                                        self.derive_channel_keys(descriptor.channel_value_satoshis, &descriptor.channel_keys_id),
                                                        descriptor.channel_keys_id));
                                        }
-                                       spend_tx.input[input_idx].witness = keys_cache.as_ref().unwrap().0.sign_counterparty_payment_input(&spend_tx, input_idx, &descriptor, &secp_ctx).unwrap();
+                                       spend_tx.input[input_idx].witness = 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 {
@@ -1004,7 +1041,7 @@ impl KeysManager {
                                                        self.derive_channel_keys(descriptor.channel_value_satoshis, &descriptor.channel_keys_id),
                                                        descriptor.channel_keys_id));
                                        }
-                                       spend_tx.input[input_idx].witness = keys_cache.as_ref().unwrap().0.sign_dynamic_p2wsh_input(&spend_tx, input_idx, &descriptor, &secp_ctx).unwrap();
+                                       spend_tx.input[input_idx].witness = 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 {
@@ -1029,6 +1066,10 @@ impl KeysManager {
                                                assert_eq!(pubkey.key, 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!(&bip143::SigHashCache::new(&spend_tx).signature_hash(input_idx, &witness_script, output.value, SigHashType::All)[..]);
                                        let sig = secp_ctx.sign(&sighash, &secret.private_key.key);
                                        spend_tx.input[input_idx].witness.push(sig.serialize_der().to_vec());
@@ -1089,11 +1130,12 @@ impl KeysInterface for KeysManager {
        }
 
        fn read_chan_signer(&self, reader: &[u8]) -> Result<Self::Signer, DecodeError> {
-               InMemorySigner::read(&mut io::Cursor::new(reader))
+               InMemorySigner::read(&mut io::Cursor::new(reader), self.get_node_secret())
        }
 
-       fn sign_invoice(&self, invoice_preimage: Vec<u8>) -> Result<RecoverableSignature, ()> {
-               Ok(self.secp_ctx.sign_recoverable(&hash_to_message!(&Sha256::hash(&invoice_preimage)), &self.get_node_secret()))
+       fn sign_invoice(&self, hrp_bytes: &[u8], invoice_data: &[u5]) -> Result<RecoverableSignature, ()> {
+               let preimage = construct_invoice_preimage(&hrp_bytes, &invoice_data);
+               Ok(self.secp_ctx.sign_recoverable(&hash_to_message!(&Sha256::hash(&preimage)), &self.get_node_secret()))
        }
 }