rust-crypto-lib-base

This crate provides core cryptographic primitives and message hashing utilities for StarkNet-based applications, with a focus on interoperability and off-chain message construction. The code is designed to be called from other languages (such as Python or JavaScript) and provides a set of Rust functions and types for working with StarkNet signatures, domain separation, and message hashing.

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File Overview

src/lib.rs

This is the main entry point of the library. It provides:

• Key Derivation and Signing

  • grind_key: Deterministically derives a StarkNet-compatible private key from a seed using SHA-256 and modular reduction.
  • get_private_key_from_eth_signature: Extracts a private key from an Ethereum signature, using the grind_key function.
  • sign_message: Signs a message using StarkNet ECDSA and returns a StarkSignature struct.

• Message Hashing Functions

  • get_order_hash: Computes the hash for an order message, given all order parameters as strings.
  • get_transfer_hash: Computes the hash for a transfer message, given all transfer parameters as strings.
  • get_withdrawal_hash: Computes the hash for a withdrawal message, given all withdrawal parameters as strings.

• Types

  • StarkSignature: Holds the r, s, and v components of a StarkNet ECDSA signature.

• Testing

  • Comprehensive unit tests for key derivation, signing, and message hash computation.

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src/starknet_messages.rs

This module defines the core data structures and hashing logic for StarkNet off-chain messages:

• Traits

  • Hashable: For types that can be hashed with a Poseidon hash and a selector.
  • OffChainMessage: For types that represent off-chain messages and can be hashed with domain separation and a public key.

• Domain and Message Types

  • StarknetDomain: Represents the domain for message separation (name, version, chain_id, revision).
  • AssetId, PositionId, AssetAmount, Timestamp: Basic types for message construction.
  • Order, TransferArgs, WithdrawalArgs: Main message types for orders, transfers, and withdrawals.

• Hash Implementations

  • Each message type implements Hashable and provides a unique selector and hashing logic using the Poseidon hash function.

• Constants

  • SEPOLIA_DOMAIN: A pre-defined domain for the Sepolia testnet.

• Testing

  • Unit tests for selectors, hashing, and message hash computation for all message types.

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Usage

• Hashing and Signing:
  Use the functions in lib.rs to derive keys, sign messages, and compute message hashes for StarkNet off-chain protocols.
• Extending Message Types:
  Implement the Hashable and OffChainMessage traits for new message types as needed.
• Interoperability:
  All public functions are designed to accept string arguments for easy FFI or WASM integration.

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Example

use rust_crypto_lib_base::{get_order_hash, sign_message, get_private_key_from_eth_signature};

// Compute an order hash
let hash = get_order_hash(
    "1".to_string(), "0x2".to_string(), "100".to_string(), "0x1".to_string(),
    "-156".to_string(), "0x1".to_string(), "74".to_string(), "100".to_string(),
    "123".to_string(), "0x...".to_string(), "Perpetuals".to_string(), "v0".to_string(),
    "SN_SEPOLIA".to_string(), "1".to_string()
)?;

// Sign a message
let private_key = get_private_key_from_eth_signature("0x...")?;
let signature = sign_message(&hash, &private_key)?;