Refactor ChainXBridge by precompile contracts

contracts/ChainXBridge.sol

@@ -1,21 +1,17 @@
 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.13;
 
+import "./SystemWithdraw.sol";
+
 interface IBitcoinAssets {
  function burnFrom(address account, uint256 amount) external;
 }
 
 contract ChainXBridge {
- uint constant MIN_BTC_TRANSFER_VALUE = 10_000_000_000;
  address public cold;
- uint64 public chainId;
  uint64 public nonce;
 
- event Balance(uint256);
-
- event SwapOut(
- uint64 fromChainId,
- uint64 toChainId,
+ event Withdraw(
  address sender,
  string receiver,
  uint256 amount,
@@ -28,31 +24,37 @@ contract ChainXBridge {
  _;
  }
 
- constructor(
- address _cold,
- uint64 _chainId
- ){
+ constructor(address _cold){
  require(_cold != address(0), "InvalidCold");
- require(_chainId != 0, "InvalidChainId");
 
  cold = _cold;
- chainId = _chainId;
  nonce = 0;
  }
 
+ function withdrawBTC(
+ uint256 value,
+ string calldata btcAddr
+ ) external autoIncreaseNonce returns (bool) {
+ return SystemWithdraw.withdrawBTC(value, btcAddr);
+ }
 
+ function withdrawPCX(
+ uint256 value,
+ bytes32 chainxPubkey
+ ) external autoIncreaseNonce returns (bool) {
+ return SystemWithdraw.withdrawPCX(value, chainxPubkey);
+ }
 
- function swap_out(
- uint64 toChainId,
+ function withdraw(
  string calldata receiver,
  address token,
  uint256 amount,
  uint256 estGas
  ) external payable autoIncreaseNonce {
  require((cold != address(0)), "InvalidCold");
  // Less than MIN_BTC_TRANSFER_VALUE as 0
+ uint256 MIN_BTC_TRANSFER_VALUE = SystemWithdraw.MIN_BTC_TRANSFER_VALUE;
  estGas = estGas / MIN_BTC_TRANSFER_VALUE * MIN_BTC_TRANSFER_VALUE;
- emit Balance(estGas);
  require(estGas >= MIN_BTC_TRANSFER_VALUE, "InvalidEstGas");
  require(msg.value >= estGas, "ValueErr");
 
@@ -64,9 +66,7 @@ contract ChainXBridge {
 
  IBitcoinAssets(token).burnFrom(msg.sender, amount);
 
- emit SwapOut(
- chainId,
- toChainId,
+ emit Withdraw(
  msg.sender,
  receiver,
  amount,

contracts/SystemWithdraw.sol

@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: MIT
+
+pragma solidity ^0.8.0;
+
+library SystemWithdraw {
+ address constant private precompile = address(0x403);
+ uint256 constant MIN_BTC_TRANSFER_VALUE = 10_000_000_000;
+
+ event WithdrawBTC(address from, uint256 amount, string to);
+ event WithdrawPCX(address from, uint256 amount, bytes32 to);
+
+ function withdrawBTC(
+ uint256 value,
+ string calldata btcAddr
+ ) public returns (bool) {
+ (bool success, bytes memory returnData) = precompile.delegatecall(abi.encodePacked(false, value, btcAddr));
+
+ require(success, string(returnData));
+
+ emit WithdrawBTC(msg.sender, value / MIN_BTC_TRANSFER_VALUE, btcAddr);
+
+ return success;
+ }
+
+ function withdrawPCX(
+ uint256 value,
+ bytes32 chainxPubkey
+ ) public returns (bool) {
+ (bool success, bytes memory returnData) = precompile.delegatecall(abi.encodePacked(true, value, chainxPubkey));
+
+ require(success, string(returnData));
+
+ emit WithdrawPCX(msg.sender, value, chainxPubkey);
+
+ return success;
+ }
+}

runtime/dev/src/lib.rs

@@ -116,6 +116,8 @@ use pallet_evm::{
 use sp_core::{H160, U256};
 use sp_runtime::traits::{Dispatchable, PostDispatchInfoOf};
 mod precompiles;
+mod withdraw;
+
 pub use precompiles::ChainXPrecompiles;
 
 /// This runtime version.

runtime/dev/src/precompiles.rs

@@ -25,7 +25,7 @@ where
  /// Return all addresses that contain precompiles. This can be used to populate dummy code
  /// under the precompile.
  pub fn used_addresses() -> sp_std::vec::Vec<H160> {
- sp_std::vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 1024, 1025, 1026]
+ sp_std::vec![1, 2, 3, 4, 5, 6, 7, 8, 9, 1024, 1025, 1026, 1027]
  .into_iter()
  .map(hash)
  .collect()
@@ -38,7 +38,9 @@ where
 /// 2048-4095 ChainX specific precompiles
 impl<R> PrecompileSet for ChainXPrecompiles<R>
 where
- R: pallet_evm::Config,
+ R: xpallet_assets_bridge::Config
+ + xpallet_gateway_common::Config
+ + xpallet_gateway_records::Config,
  Dispatch<R>: Precompile,
 {
  fn execute(
@@ -70,6 +72,9 @@ where
  a if a == hash(1026) => Some(ECRecoverPublicKey::execute(
  input, target_gas, context, is_static,
  )),
+ a if a == hash(1027) => Some(crate::withdraw::Withdraw::<R>::execute(
+ input, target_gas, context, is_static,
+ )),
  _ => None,
  }
  }