Introduce precompiles to manage ERC20 connector

.github/workflows/lints.yml

@@ -34,8 +34,23 @@ jobs:
           toolchain: nightly-2021-03-25
           override: true
           components: clippy
-      - name: Run cargo clippy
+      - run: make etc/eth-contracts/res/EvmErc20.bin
+      - name: Run Contract cargo clippy
         uses: actions-rs/cargo@v1
         with:
           command: clippy
           args: --no-default-features --features=contract -- -D warnings
+      - name: Run cargo clippy
+        uses: actions-rs/cargo@v1
+        with:
+          command: clippy
+
+  contracts:
+    name: eth-contracts
+    runs-on: ubuntu-latest
+    steps:
+      - name: Clone the repository
+        uses: actions/checkout@v2
+      - name: Run yarn lint
+        working-directory: etc/eth-contracts
+        run: yarn && yarn lint

.gitignore

@@ -13,8 +13,16 @@
 # Rust artifacts
 /*.wasm
 /target/
-etc/state-migration-test/target/
 
+# Solidity artifacts
+artifacts/
+cache/
 node_modules/
+res/
+
+# Other
+etc/state-migration-test/target/
+
+node_modules/*
 artifacts/
-cache
+cache

Cargo.toml

@@ -41,8 +41,8 @@ rpath = false
 blake2 = { git = "https://github.com/near/near-blake2.git", version = "0.9.1", default-features = false }
 borsh = { version = "0.8.2", default-features = false }
 bn = { package = "aurora-bn", git = "https://github.com/aurora-is-near/aurora-bn.git", default-features = false }
-evm = { version = "0.27.0", default-features = false }
-evm-core = { version = "0.27.1", default-features = false }
+evm = { version = "0.28.0", default-features = false }
+evm-core = { version = "0.28.0", default-features = false }
 libsecp256k1 = { version = "0.3.5", default-features = false }
 num = { version = "0.4.0", default-features = false, features = ["alloc"] }
 primitive-types = { version = "0.9.0", default-features = false, features = ["rlp"] }
@@ -72,6 +72,8 @@ libsecp256k1 = "0.3.5"
 rand = "0.7.3"
 criterion = "0.3.4"
 git2 = "0.13"
+lazy-static-include = "3.1.1"
+base64 = "0.13.0"
 
 [features]
 default = ["sha2", "std"]

Makefile

@@ -1,6 +1,6 @@
 CARGO = cargo
 NEAR  = near
-FEATURES = contract,log
+FEATURES = contract,log,exit-precompiles
 
 ifeq ($(evm-bully),yes)
   FEATURES := $(FEATURES),evm_bully
@@ -13,11 +13,14 @@ release: release.wasm
 release.wasm: target/wasm32-unknown-unknown/release/aurora_engine.wasm
 	ln -sf $< $@
 
-target/wasm32-unknown-unknown/release/aurora_engine.wasm: Cargo.toml Cargo.lock $(wildcard src/*.rs)
+target/wasm32-unknown-unknown/release/aurora_engine.wasm: Cargo.toml Cargo.lock $(shell find src -name "*.rs") etc/eth-contracts/res/EvmErc20.bin
 	RUSTFLAGS='-C link-arg=-s' $(CARGO) build --target wasm32-unknown-unknown --release --no-default-features --features=$(FEATURES) -Z avoid-dev-deps
-	ls -l target/wasm32-unknown-unknown/release/aurora_engine.wasm 
+	ls -l target/wasm32-unknown-unknown/release/aurora_engine.wasm
 
-etc/eth-contracts/artifacts/contracts/StateTest.sol/StateTest.json: $(shell find etc/eth-contracts/contracts -name "*.sol") etc/eth-contracts/package.json
+etc/eth-contracts/res/EvmErc20.bin: $(shell find etc/eth-contracts/contracts -name "*.sol") etc/eth-contracts/package.json
+	cd etc/eth-contracts && yarn && yarn build
+
+etc/eth-contracts/artifacts/contracts/test/StateTest.sol/StateTest.json: $(shell find etc/eth-contracts/contracts -name "*.sol") etc/eth-contracts/package.json
 	cd etc/eth-contracts && yarn && yarn build
 
 debug: debug.wasm
@@ -28,12 +31,12 @@ debug.wasm: target/wasm32-unknown-unknown/debug/aurora_engine.wasm
 target/wasm32-unknown-unknown/debug/aurora_engine.wasm: Cargo.toml Cargo.lock $(wildcard src/*.rs)
 	$(CARGO) build --target wasm32-unknown-unknown --no-default-features --features=$(FEATURES) -Z avoid-dev-deps
 
-test-build: etc/eth-contracts/artifacts/contracts/StateTest.sol/StateTest.json
-	RUSTFLAGS='-C link-arg=-s' $(CARGO) build --target wasm32-unknown-unknown --release --no-default-features --features=contract,integration-test -Z avoid-dev-deps
-	ln -sf target/wasm32-unknown-unknown/release/aurora_engine.wasm release.wasm 
-	ls -l target/wasm32-unknown-unknown/release/aurora_engine.wasm 
+test-build: etc/eth-contracts/artifacts/contracts/test/StateTest.sol/StateTest.json etc/eth-contracts/res/EvmErc20.bin
+	RUSTFLAGS='-C link-arg=-s' $(CARGO) build --target wasm32-unknown-unknown --release --no-default-features --features=contract,integration-test,exit-precompiles -Z avoid-dev-deps
+	ln -sf target/wasm32-unknown-unknown/release/aurora_engine.wasm release.wasm
+	ls -l target/wasm32-unknown-unknown/release/aurora_engine.wasm
 
-.PHONY: all release debug
+.PHONY: all release debug eth-contracts
 
 deploy: release.wasm
 	$(NEAR) deploy --account-id=$(or $(NEAR_EVM_ACCOUNT),aurora.test.near) --wasm-file=$<

etc/eth-contracts/.soliumignore

@@ -1 +1,9 @@
 node_modules
+
+# solium fails to run linter in Tester.sol
+# see issue for more details: https://github.com/duaraghav8/Ethlint/issues/293
+contracts/test/Tester.sol
+
+# solium fails to run linter in Tester.sol
+# see issue for more details: https://github.com/duaraghav8/Ethlint/issues/294
+contracts/test/StateTest.sol

etc/eth-contracts/.soliumrc.json

@@ -20,4 +20,4 @@
     "security/no-block-members": ["off"],
     "security/no-inline-assembly": ["warning"]
   }
-}
+}

etc/eth-contracts/contracts/AdminControlled.sol

@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: CC0 1.0 Universal
+pragma solidity ^0.8.0;
+
+
+contract AdminControlled {
+    address public admin;
+    uint public paused;
+
+    constructor(address _admin, uint flags) {
+        admin = _admin;
+
+        // Add the possibility to set pause flags on the initialization
+        paused = flags;
+    }
+
+    modifier onlyAdmin {
+        require(msg.sender == admin);
+        _;
+    }
+
+    modifier pausable(uint flag) {
+        require((paused & flag) == 0 || msg.sender == admin);
+        _;
+    }
+
+    function adminPause(uint flags) public onlyAdmin {
+        paused = flags;
+    }
+
+    function adminSstore(uint key, uint value) public onlyAdmin {
+        assembly {
+            sstore(key, value)
+        }
+    }
+
+    function adminSendEth(address payable destination, uint amount) public onlyAdmin {
+        destination.transfer(amount);
+    }
+
+    function adminReceiveEth() public payable onlyAdmin {}
+
+    function adminDelegatecall(address target, bytes memory data) public payable onlyAdmin returns (bytes memory) {
+        (bool success, bytes memory rdata) = target.delegatecall(data);
+        require(success);
+        return rdata;
+    }
+}

etc/eth-contracts/contracts/EvmErc20.sol

@@ -0,0 +1,55 @@
+// SPDX-License-Identifier: CC0 1.0 Universal
+pragma solidity ^0.8.0;
+
+import "@openzeppelin/contracts/utils/Context.sol";
+import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
+import "./AdminControlled.sol";
+import "./IExit.sol";
+
+
+/**
+ * @title SimpleToken
+ * @dev Very simple ERC20 Token example, where all tokens are pre-assigned to the creator.
+ * Note they can later distribute these tokens as they wish using `transfer` and other
+ * `ERC20` functions.
+ */
+contract EvmErc20 is Context, ERC20, AdminControlled, IExit {
+    uint8 private _decimals;
+
+    constructor (string memory name, string memory symbol, uint8 decimal, address admin)  ERC20(name, symbol) AdminControlled(admin, 0) {
+        _decimals = decimal;
+    }
+
+    function decimals() public view override returns (uint8) {
+        return _decimals;
+    }
+
+    function mint(address account, uint256 amount) public onlyAdmin {
+        _mint(account, amount);
+    }
+
+    function withdrawToNear(bytes memory recipient, uint256 amount) external override {
+        _burn(msg.sender, amount);
+
+        bytes32 amount_b = bytes32(amount);
+        bytes memory input = abi.encodePacked("\x01", amount_b, recipient);
+        uint input_size = 1 + 32 + recipient.length;
+
+        assembly {
+            let res := staticcall(gas(), 0xe9217bc70b7ed1f598ddd3199e80b093fa71124f, add(input, 32), input_size, 0, 32)
+        }
+    }
+
+    function withdrawToEthereum(address recipient, uint256 amount) external override {
+        _burn(msg.sender, amount);
+
+        bytes32 amount_b = bytes32(amount);
+        bytes20 recipient_b = bytes20(recipient);
+        bytes memory input = abi.encodePacked("\x01", amount_b, recipient_b);
+        uint input_size = 1 + 32 + 20;
+
+        assembly {
+            let res := staticcall(gas(), 0xb0bd02f6a392af548bdf1cfaee5dfa0eefcc8eab, add(input, 32), input_size, 0, 32)
+        }
+    }
+}

etc/eth-contracts/contracts/IExit.sol

@@ -0,0 +1,8 @@
+// SPDX-License-Identifier: CC0 1.0 Universal
+pragma solidity ^0.8.0;
+
+interface IExit {
+    function withdrawToNear(bytes memory recipient, uint256 amount) external;
+
+    function withdrawToEthereum(address recipient, uint256 amount) external;
+}

etc/eth-contracts/contracts/StateTest.sol → etc/eth-contracts/contracts/test/StateTest.sol

@@ -1,10 +1,11 @@
+// SPDX-License-Identifier: CC0 1.0 Universal
 pragma solidity ^0.8.0;
 
+
 contract SelfDestruct {
     uint256 public counter;
 
-    constructor() public {
-    }
+    constructor() { }
 
     function increase() public {
         counter += 1;
@@ -15,9 +16,9 @@ contract SelfDestruct {
     }
 }
 
+
 contract SelfDestructFactory {
-    constructor() public {
-    }
+    constructor() { }
 
     function deploy() public returns(address) {
         address addr = address(new SelfDestruct{salt: bytes32(uint256(0x1234))}());

etc/eth-contracts/contracts/test/Tester.sol

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: CC0 1.0 Universal
+pragma solidity ^0.8.0;
+
+import "../IExit.sol";
+
+contract Tester {
+    IExit public erc20Token;
+
+    constructor (IExit _erc20Token) {
+        erc20Token = _erc20Token;
+    }
+
+    function helloWorld(string memory name) public pure returns(string memory) {
+        return string(abi.encodePacked("Hello ", name, "!"));
+    }
+
+    // Use flag to indicate if should withdraw to NEAR (true) or to Ethereum (false)
+    function withdraw(bool toNear) external {
+        if (toNear) {
+            erc20Token.withdrawToNear("target.aurora", 1);
+        } else {
+            erc20Token.withdrawToEthereum(0xE0f5206BBD039e7b0592d8918820024e2a7437b9, 1);
+        }
+    }
+
+    function withdrawAndFail(bool toNear) external {
+        this.withdraw(toNear);
+        require(false);
+    }
+
+    function tryWithdrawAndAvoidFail(bool toNear) external {
+        try this.withdrawAndFail(toNear) {
+            require(false);
+        } catch {
+        }
+    }
+
+    function tryWithdrawAndAvoidFailAndSucceed(bool toNear) external {
+        this.tryWithdrawAndAvoidFail(toNear);
+        this.withdraw(toNear);
+    }
+}

etc/eth-contracts/main.js

@@ -0,0 +1,8 @@
+const fs = require('fs');
+const path = require('path');
+const artifact = require(process.argv[2]);
+if (!fs.existsSync('res')) {
+    fs.mkdirSync('res');
+}
+fs.writeFileSync(path.join('res', 'EvmErc20.hex'), artifact.bytecode);
+fs.writeFileSync(path.join('res', 'EvmErc20.bin'), Buffer.from(artifact.bytecode.substring(2), 'hex'));

etc/eth-contracts/package.json

@@ -23,7 +23,8 @@
     "solium": "^1.2.5"
   },
   "scripts": {
-    "build": "hardhat compile",
+    "compile": "hardhat compile",
+    "build": "yarn compile && node main.js ./artifacts/contracts/EvmErc20.sol/EvmErc20.json",
     "test": "hardhat test",
     "coverage": "hardhat coverage",
     "lint:js": "eslint .",
@@ -33,4 +34,4 @@
     "lint": "yarn lint:js && yarn lint:sol",
     "lint:fix": "yarn lint:js:fix && yarn lint:sol:fix"
   }
-}
+}