Break Ethereum Deployer into crate

processor/ethereum/primitives/Cargo.toml

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+[package]
+name = "serai-processor-ethereum-primitives"
+version = "0.1.0"
+description = "Primitives for Serai's Ethereum Processor"
+license = "AGPL-3.0-only"
+repository = "https://github.com/serai-dex/serai/tree/develop/processor/ethereum/primitives"
+authors = ["Luke Parker <lukeparker5132@gmail.com>"]
+edition = "2021"
+publish = false
+rust-version = "1.79"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = ["--cfg", "docsrs"]
+
+[lints]
+workspace = true
+
+[dependencies]
+group = { version = "0.13", default-features = false }
+k256 = { version = "^0.13.1", default-features = false, features = ["std", "arithmetic"] }
+
+alloy-core = { version = "0.8", default-features = false }
+alloy-consensus = { version = "0.3", default-features = false, features = ["k256"] }

processor/ethereum/primitives/LICENSE

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+AGPL-3.0-only license
+
+Copyright (c) 2022-2024 Luke Parker
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License Version 3 as
+published by the Free Software Foundation.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.

processor/ethereum/primitives/README.md

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+# Ethereum Processor Primitives
+
+This library contains miscellaneous primitives and helper functions.

processor/ethereum/primitives/src/lib.rs

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+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![deny(missing_docs)]
+
+use group::ff::PrimeField;
+use k256::{elliptic_curve::ops::Reduce, U256, Scalar};
+
+use alloy_core::primitives::{Parity, Signature};
+use alloy_consensus::{SignableTransaction, Signed, TxLegacy};
+
+/// The Keccak256 hash function.
+pub fn keccak256(data: impl AsRef<[u8]>) -> [u8; 32] {
+  alloy_core::primitives::keccak256(data.as_ref()).into()
+}
+
+/// Deterministically sign a transaction.
+///
+/// This function panics if passed a transaction with a non-None chain ID.
+pub fn deterministically_sign(tx: &TxLegacy) -> Signed<TxLegacy> {
+  pub fn hash_to_scalar(data: impl AsRef<[u8]>) -> Scalar {
+    <Scalar as Reduce<U256>>::reduce_bytes(&keccak256(data).into())
+  }
+
+  assert!(
+    tx.chain_id.is_none(),
+    "chain ID was Some when deterministically signing a TX (causing a non-deterministic signer)"
+  );
+
+  let sig_hash = tx.signature_hash().0;
+  let mut r = hash_to_scalar([sig_hash.as_slice(), b"r"].concat());
+  let mut s = hash_to_scalar([sig_hash.as_slice(), b"s"].concat());
+  loop {
+    // Create the signature
+    let r_bytes: [u8; 32] = r.to_repr().into();
+    let s_bytes: [u8; 32] = s.to_repr().into();
+    let v = Parity::NonEip155(false);
+    let signature = Signature::from_scalars_and_parity(r_bytes.into(), s_bytes.into(), v).unwrap();
+
+    // Check if this is a valid signature
+    let tx = tx.clone().into_signed(signature);
+    if tx.recover_signer().is_ok() {
+      return tx;
+    }
+
+    // Re-hash until valid
+    r = hash_to_scalar(r_bytes);
+    s = hash_to_scalar(s_bytes);
+  }
+}