Bitcoin Output/Transaction definitions

processor/bitcoin/src/lib.rs

@@ -2,7 +2,15 @@
 #![doc = include_str!("../README.md")]
 #![deny(missing_docs)]
 
-use std::{sync::OnceLock, time::Duration, io, collections::HashMap};
+#[global_allocator]
+static ALLOCATOR: zalloc::ZeroizingAlloc<std::alloc::System> =
+  zalloc::ZeroizingAlloc(std::alloc::System);
+
+mod output;
+mod transaction;
+
+/*
+use std::{sync::LazyLock, time::Duration, io, collections::HashMap};
 
 use async_trait::async_trait;
 
@@ -49,127 +57,9 @@ use serai_client::{
   primitives::{MAX_DATA_LEN, Coin, NetworkId, Amount, Balance},
   networks::bitcoin::Address,
 };
+*/
 
-use crate::{
-  networks::{
-    NetworkError, Block as BlockTrait, OutputType, Output as OutputTrait,
-    Transaction as TransactionTrait, SignableTransaction as SignableTransactionTrait,
-    Eventuality as EventualityTrait, EventualitiesTracker, Network, UtxoNetwork,
-  },
-  Payment,
-  multisigs::scheduler::utxo::Scheduler,
-};
-
-#[derive(Clone, PartialEq, Eq, Debug)]
-pub struct OutputId(pub [u8; 36]);
-impl Default for OutputId {
-  fn default() -> Self {
-    Self([0; 36])
-  }
-}
-impl AsRef<[u8]> for OutputId {
-  fn as_ref(&self) -> &[u8] {
-    self.0.as_ref()
-  }
-}
-impl AsMut<[u8]> for OutputId {
-  fn as_mut(&mut self) -> &mut [u8] {
-    self.0.as_mut()
-  }
-}
-
-#[derive(Clone, PartialEq, Eq, Debug)]
-pub struct Output {
-  kind: OutputType,
-  presumed_origin: Option<Address>,
-  output: ReceivedOutput,
-  data: Vec<u8>,
-}
-
-impl OutputTrait<Bitcoin> for Output {
-  type Id = OutputId;
-
-  fn kind(&self) -> OutputType {
-    self.kind
-  }
-
-  fn id(&self) -> Self::Id {
-    let mut res = OutputId::default();
-    self.output.outpoint().consensus_encode(&mut res.as_mut()).unwrap();
-    debug_assert_eq!(
-      {
-        let mut outpoint = vec![];
-        self.output.outpoint().consensus_encode(&mut outpoint).unwrap();
-        outpoint
-      },
-      res.as_ref().to_vec()
-    );
-    res
-  }
-
-  fn tx_id(&self) -> [u8; 32] {
-    let mut hash = *self.output.outpoint().txid.as_raw_hash().as_byte_array();
-    hash.reverse();
-    hash
-  }
-
-  fn key(&self) -> ProjectivePoint {
-    let script = &self.output.output().script_pubkey;
-    assert!(script.is_p2tr());
-    let Instruction::PushBytes(key) = script.instructions_minimal().last().unwrap().unwrap() else {
-      panic!("last item in v1 Taproot script wasn't bytes")
-    };
-    let key = XOnlyPublicKey::from_slice(key.as_ref())
-      .expect("last item in v1 Taproot script wasn't x-only public key");
-    Secp256k1::read_G(&mut key.public_key(Parity::Even).serialize().as_slice()).unwrap() -
-      (ProjectivePoint::GENERATOR * self.output.offset())
-  }
-
-  fn presumed_origin(&self) -> Option<Address> {
-    self.presumed_origin.clone()
-  }
-
-  fn balance(&self) -> Balance {
-    Balance { coin: Coin::Bitcoin, amount: Amount(self.output.value()) }
-  }
-
-  fn data(&self) -> &[u8] {
-    &self.data
-  }
-
-  fn write<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
-    self.kind.write(writer)?;
-    let presumed_origin: Option<Vec<u8>> = self.presumed_origin.clone().map(Into::into);
-    writer.write_all(&presumed_origin.encode())?;
-    self.output.write(writer)?;
-    writer.write_all(&u16::try_from(self.data.len()).unwrap().to_le_bytes())?;
-    writer.write_all(&self.data)
-  }
-
-  fn read<R: io::Read>(mut reader: &mut R) -> io::Result<Self> {
-    Ok(Output {
-      kind: OutputType::read(reader)?,
-      presumed_origin: {
-        let mut io_reader = scale::IoReader(reader);
-        let res = Option::<Vec<u8>>::decode(&mut io_reader)
-          .unwrap()
-          .map(|address| Address::try_from(address).unwrap());
-        reader = io_reader.0;
-        res
-      },
-      output: ReceivedOutput::read(reader)?,
-      data: {
-        let mut data_len = [0; 2];
-        reader.read_exact(&mut data_len)?;
-
-        let mut data = vec![0; usize::from(u16::from_le_bytes(data_len))];
-        reader.read_exact(&mut data)?;
-        data
-      },
-    })
-  }
-}
-
+/*
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
 pub struct Fee(u64);
 
@@ -201,71 +91,6 @@ impl TransactionTrait<Bitcoin> for Transaction {
   }
 }
 
-#[derive(Clone, PartialEq, Eq, Debug)]
-pub struct Eventuality([u8; 32]);
-
-#[derive(Clone, PartialEq, Eq, Default, Debug)]
-pub struct EmptyClaim;
-impl AsRef<[u8]> for EmptyClaim {
-  fn as_ref(&self) -> &[u8] {
-    &[]
-  }
-}
-impl AsMut<[u8]> for EmptyClaim {
-  fn as_mut(&mut self) -> &mut [u8] {
-    &mut []
-  }
-}
-
-impl EventualityTrait for Eventuality {
-  type Claim = EmptyClaim;
-  type Completion = Transaction;
-
-  fn lookup(&self) -> Vec<u8> {
-    self.0.to_vec()
-  }
-
-  fn read<R: io::Read>(reader: &mut R) -> io::Result<Self> {
-    let mut id = [0; 32];
-    reader
-      .read_exact(&mut id)
-      .map_err(|_| io::Error::other("couldn't decode ID in eventuality"))?;
-    Ok(Eventuality(id))
-  }
-  fn serialize(&self) -> Vec<u8> {
-    self.0.to_vec()
-  }
-
-  fn claim(_: &Transaction) -> EmptyClaim {
-    EmptyClaim
-  }
-  fn serialize_completion(completion: &Transaction) -> Vec<u8> {
-    let mut buf = vec![];
-    completion.consensus_encode(&mut buf).unwrap();
-    buf
-  }
-  fn read_completion<R: io::Read>(reader: &mut R) -> io::Result<Transaction> {
-    Transaction::consensus_decode(&mut io::BufReader::with_capacity(0, reader))
-      .map_err(|e| io::Error::other(format!("{e}")))
-  }
-}
-
-#[derive(Clone, Debug)]
-pub struct SignableTransaction {
-  actual: BSignableTransaction,
-}
-impl PartialEq for SignableTransaction {
-  fn eq(&self, other: &SignableTransaction) -> bool {
-    self.actual == other.actual
-  }
-}
-impl Eq for SignableTransaction {}
-impl SignableTransactionTrait for SignableTransaction {
-  fn fee(&self) -> u64 {
-    self.actual.fee()
-  }
-}
-
 #[async_trait]
 impl BlockTrait<Bitcoin> for Block {
   type Id = [u8; 32];
@@ -944,3 +769,4 @@ impl Network for Bitcoin {
 impl UtxoNetwork for Bitcoin {
   const MAX_INPUTS: usize = MAX_INPUTS;
 }
+*/

processor/bitcoin/src/output.rs

@@ -0,0 +1,133 @@
+use std::io;
+
+use ciphersuite::{Ciphersuite, Secp256k1};
+
+use bitcoin_serai::{
+  bitcoin::{
+    hashes::Hash as HashTrait,
+    key::{Parity, XOnlyPublicKey},
+    consensus::Encodable,
+    script::Instruction,
+  },
+  wallet::ReceivedOutput as WalletOutput,
+};
+
+use scale::{Encode, Decode, IoReader};
+use borsh::{BorshSerialize, BorshDeserialize};
+
+use serai_client::{
+  primitives::{Coin, Amount, Balance, ExternalAddress},
+  networks::bitcoin::Address,
+};
+
+use primitives::{OutputType, ReceivedOutput};
+
+#[derive(Clone, PartialEq, Eq, Hash, Debug, Encode, Decode, BorshSerialize, BorshDeserialize)]
+pub(crate) struct OutputId([u8; 36]);
+impl Default for OutputId {
+  fn default() -> Self {
+    Self([0; 36])
+  }
+}
+impl AsRef<[u8]> for OutputId {
+  fn as_ref(&self) -> &[u8] {
+    self.0.as_ref()
+  }
+}
+impl AsMut<[u8]> for OutputId {
+  fn as_mut(&mut self) -> &mut [u8] {
+    self.0.as_mut()
+  }
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub(crate) struct Output {
+  kind: OutputType,
+  presumed_origin: Option<Address>,
+  output: WalletOutput,
+  data: Vec<u8>,
+}
+
+impl ReceivedOutput<<Secp256k1 as Ciphersuite>::G, Address> for Output {
+  type Id = OutputId;
+  type TransactionId = [u8; 32];
+
+  fn kind(&self) -> OutputType {
+    self.kind
+  }
+
+  fn id(&self) -> Self::Id {
+    let mut id = OutputId::default();
+    self.output.outpoint().consensus_encode(&mut id.as_mut()).unwrap();
+    id
+  }
+
+  fn transaction_id(&self) -> Self::TransactionId {
+    self.output.outpoint().txid.to_raw_hash().to_byte_array()
+  }
+
+  fn key(&self) -> <Secp256k1 as Ciphersuite>::G {
+    // We read the key from the script pubkey so we don't have to independently store it
+    let script = &self.output.output().script_pubkey;
+
+    // These assumptions are safe since it's an output we successfully scanned
+    assert!(script.is_p2tr());
+    let Instruction::PushBytes(key) = script.instructions_minimal().last().unwrap().unwrap() else {
+      panic!("last item in v1 Taproot script wasn't bytes")
+    };
+    let key = XOnlyPublicKey::from_slice(key.as_ref())
+      .expect("last item in v1 Taproot script wasn't a valid x-only public key");
+
+    // Convert to a full key
+    let key = key.public_key(Parity::Even);
+    // Convert to a k256 key (from libsecp256k1)
+    let output_key = Secp256k1::read_G(&mut key.serialize().as_slice()).unwrap();
+    // The output's key minus the output's offset is the root key
+    output_key - (<Secp256k1 as Ciphersuite>::G::GENERATOR * self.output.offset())
+  }
+
+  fn presumed_origin(&self) -> Option<Address> {
+    self.presumed_origin.clone()
+  }
+
+  fn balance(&self) -> Balance {
+    Balance { coin: Coin::Bitcoin, amount: Amount(self.output.value()) }
+  }
+
+  fn data(&self) -> &[u8] {
+    &self.data
+  }
+
+  fn write<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
+    self.kind.write(writer)?;
+    let presumed_origin: Option<ExternalAddress> = self.presumed_origin.clone().map(Into::into);
+    writer.write_all(&presumed_origin.encode())?;
+    self.output.write(writer)?;
+    writer.write_all(&u16::try_from(self.data.len()).unwrap().to_le_bytes())?;
+    writer.write_all(&self.data)
+  }
+
+  fn read<R: io::Read>(mut reader: &mut R) -> io::Result<Self> {
+    Ok(Output {
+      kind: OutputType::read(reader)?,
+      presumed_origin: {
+        Option::<ExternalAddress>::decode(&mut IoReader(&mut reader))
+          .map_err(|e| io::Error::other(format!("couldn't decode ExternalAddress: {e:?}")))?
+          .map(|address| {
+            Address::try_from(address)
+              .map_err(|()| io::Error::other("couldn't decode Address from ExternalAddress"))
+          })
+          .transpose()?
+      },
+      output: WalletOutput::read(reader)?,
+      data: {
+        let mut data_len = [0; 2];
+        reader.read_exact(&mut data_len)?;
+
+        let mut data = vec![0; usize::from(u16::from_le_bytes(data_len))];
+        reader.read_exact(&mut data)?;
+        data
+      },
+    })
+  }
+}

processor/bitcoin/src/transaction.rs

@@ -0,0 +1,170 @@
+use std::io;
+
+use rand_core::{RngCore, CryptoRng};
+
+use transcript::{Transcript, RecommendedTranscript};
+use ciphersuite::Secp256k1;
+use frost::{dkg::ThresholdKeys, sign::PreprocessMachine};
+
+use bitcoin_serai::{
+  bitcoin::{
+    consensus::{Encodable, Decodable},
+    ScriptBuf, Transaction as BTransaction,
+  },
+  wallet::{
+    ReceivedOutput, TransactionError, SignableTransaction as BSignableTransaction,
+    TransactionMachine,
+  },
+};
+
+use borsh::{BorshSerialize, BorshDeserialize};
+
+use serai_client::networks::bitcoin::Address;
+
+use crate::output::OutputId;
+
+#[derive(Clone, Debug)]
+pub(crate) struct Transaction(BTransaction);
+
+impl From<BTransaction> for Transaction {
+  fn from(tx: BTransaction) -> Self {
+    Self(tx)
+  }
+}
+
+impl scheduler::Transaction for Transaction {
+  fn read(reader: &mut impl io::Read) -> io::Result<Self> {
+    let tx =
+      BTransaction::consensus_decode(&mut io::BufReader::new(reader)).map_err(io::Error::other)?;
+    Ok(Self(tx))
+  }
+  fn write(&self, writer: &mut impl io::Write) -> io::Result<()> {
+    let mut writer = io::BufWriter::new(writer);
+    self.0.consensus_encode(&mut writer)?;
+    writer.into_inner()?;
+    Ok(())
+  }
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct SignableTransaction {
+  inputs: Vec<ReceivedOutput>,
+  payments: Vec<(Address, u64)>,
+  change: Option<Address>,
+  data: Option<Vec<u8>>,
+  fee_per_vbyte: u64,
+}
+
+impl SignableTransaction {
+  fn signable(self) -> Result<BSignableTransaction, TransactionError> {
+    BSignableTransaction::new(
+      self.inputs,
+      &self
+        .payments
+        .iter()
+        .cloned()
+        .map(|(address, amount)| (ScriptBuf::from(address), amount))
+        .collect::<Vec<_>>(),
+      self.change.map(ScriptBuf::from),
+      self.data,
+      self.fee_per_vbyte,
+    )
+  }
+}
+
+#[derive(Clone)]
+pub(crate) struct ClonableTransctionMachine(SignableTransaction, ThresholdKeys<Secp256k1>);
+impl PreprocessMachine for ClonableTransctionMachine {
+  type Preprocess = <TransactionMachine as PreprocessMachine>::Preprocess;
+  type Signature = <TransactionMachine as PreprocessMachine>::Signature;
+  type SignMachine = <TransactionMachine as PreprocessMachine>::SignMachine;
+
+  fn preprocess<R: RngCore + CryptoRng>(
+    self,
+    rng: &mut R,
+  ) -> (Self::SignMachine, Self::Preprocess) {
+    self
+      .0
+      .signable()
+      .expect("signing an invalid SignableTransaction")
+      .multisig(&self.1, RecommendedTranscript::new(b"Serai Processor Bitcoin Transaction"))
+      .expect("incorrect keys used for SignableTransaction")
+      .preprocess(rng)
+  }
+}
+
+impl scheduler::SignableTransaction for SignableTransaction {
+  type Transaction = Transaction;
+  type Ciphersuite = Secp256k1;
+  type PreprocessMachine = ClonableTransctionMachine;
+
+  fn read(reader: &mut impl io::Read) -> io::Result<Self> {
+    let inputs = {
+      let mut input_len = [0; 4];
+      reader.read_exact(&mut input_len)?;
+      let mut inputs = vec![];
+      for _ in 0 .. u32::from_le_bytes(input_len) {
+        inputs.push(ReceivedOutput::read(reader)?);
+      }
+      inputs
+    };
+
+    let payments = <_>::deserialize_reader(reader)?;
+    let change = <_>::deserialize_reader(reader)?;
+    let data = <_>::deserialize_reader(reader)?;
+    let fee_per_vbyte = <_>::deserialize_reader(reader)?;
+
+    Ok(Self { inputs, payments, change, data, fee_per_vbyte })
+  }
+  fn write(&self, writer: &mut impl io::Write) -> io::Result<()> {
+    writer.write_all(&u32::try_from(self.inputs.len()).unwrap().to_le_bytes())?;
+    for input in &self.inputs {
+      input.write(writer)?;
+    }
+
+    self.payments.serialize(writer)?;
+    self.change.serialize(writer)?;
+    self.data.serialize(writer)?;
+    self.fee_per_vbyte.serialize(writer)?;
+
+    Ok(())
+  }
+
+  fn id(&self) -> [u8; 32] {
+    self.clone().signable().unwrap().txid()
+  }
+
+  fn sign(self, keys: ThresholdKeys<Self::Ciphersuite>) -> Self::PreprocessMachine {
+    ClonableTransctionMachine(self, keys)
+  }
+}
+
+#[derive(Clone, PartialEq, Eq, Debug, BorshSerialize, BorshDeserialize)]
+pub(crate) struct Eventuality {
+  txid: [u8; 32],
+  singular_spent_output: Option<OutputId>,
+}
+
+impl primitives::Eventuality for Eventuality {
+  type OutputId = OutputId;
+
+  fn id(&self) -> [u8; 32] {
+    self.txid
+  }
+
+  // We define the lookup as our ID since the resolving transaction only has a singular possible ID
+  fn lookup(&self) -> Vec<u8> {
+    self.txid.to_vec()
+  }
+
+  fn singular_spent_output(&self) -> Option<Self::OutputId> {
+    self.singular_spent_output.clone()
+  }
+
+  fn read(reader: &mut impl io::Read) -> io::Result<Self> {
+    Self::deserialize_reader(reader)
+  }
+  fn write(&self, writer: &mut impl io::Write) -> io::Result<()> {
+    self.serialize(writer)
+  }
+}