diff --git a/README.md b/README.md
index d192e50..91a5c62 100644
--- a/README.md
+++ b/README.md
@@ -26,8 +26,8 @@ This repository contains contracts and scripts demonstrating this flow.
## On-chain Components
-- `OriginSettler`: Origin chain contract that user interacts with to open an ERC7683 cross-chain intent. The `open` function helps the user to form an ERC7683 intent correctly containing the `calldata` that the user wants to delegate to a filler to execute on the destination chain.
- - The `open` function also optionally lets the user include a 7702 authorization that the user wants the filler to submit on-chain on their behalf. This can be used to allow the user to set the `code` of their destination chain EOA to the `XAccount` contract.
+- `OriginSettler`: Origin chain contract that user interacts with to open an ERC7683 cross-chain intent. The `open` function helps the user to form an ERC7683 intent correctly containing the `calldata` that the user wants to delegate to a filler to execute on the destination chain. `openFor` can be used to help a user pass their signed order to a filler off-chain and subsequently allows the filler to create the 7683 order on the user's behalf. Therefore, `openFor` allows the user to experience a totally gas-free experience from origin to destination chain.
+ - The `open` functionality also optionally lets the user include a 7702 authorization that the user wants the filler to submit on-chain on their behalf. This can be used to allow the user to set the `code` of their destination chain EOA to the `XAccount` contract.
- In the 7683 order, includes the 7702 authorization data and the destination chain calldata in a [`FillInstruction`](https://eips.ethereum.org/EIPS/eip-7683#fillerdata)
- `DestinationSettler`: Destination chain contract that filler interacts with to fulfill a ERC7683 cross-chain intent. The `fill` function is used by the `filler` to credit the user's EOA with any assets that they had deposited on the `OriginSettler` when initiating the 7683 intent and subsequently execute any `calldata` on behalf of the user that was included in the 7683 intent.
- The `fill` function will delegate execution of `calldata` to the `XAccount` 7702-compatible proxy contract so it is a prerequisite that the user has already set their destination chain EOA's `code` to `XAccount` via a 7702 transaction. The authorization should submitted by the user or delegated
diff --git a/script/Counter.s.sol b/script/Counter.s.sol
deleted file mode 100644
index cdc1fe9..0000000
--- a/script/Counter.s.sol
+++ /dev/null
@@ -1,19 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-import {Script, console} from "forge-std/Script.sol";
-import {Counter} from "../src/Counter.sol";
-
-contract CounterScript is Script {
- Counter public counter;
-
- function setUp() public {}
-
- function run() public {
- vm.startBroadcast();
-
- counter = new Counter();
-
- vm.stopBroadcast();
- }
-}
diff --git a/src/Counter.sol b/src/Counter.sol
deleted file mode 100644
index aded799..0000000
--- a/src/Counter.sol
+++ /dev/null
@@ -1,14 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-contract Counter {
- uint256 public number;
-
- function setNumber(uint256 newNumber) public {
- number = newNumber;
- }
-
- function increment() public {
- number++;
- }
-}
diff --git a/src/DestinationSettler.sol b/src/DestinationSettler.sol
index 0b40680..ddc220a 100644
--- a/src/DestinationSettler.sol
+++ b/src/DestinationSettler.sol
@@ -6,7 +6,7 @@ import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {OriginSettler} from "./OriginSettler.sol";
struct Asset {
- IERC20 token;
+ address token;
uint256 amount;
}
@@ -77,8 +77,8 @@ contract DestinationSettler {
function _fundUserAndApproveXAccount(CallByUser memory call) internal {
// TODO: Link the escrowed funds back to the user in case the delegation step fails, we don't want
// user to lose access to funds.
- call.asset.token.safeTransferFrom(msg.sender, address(this), call.asset.amount);
- call.asset.token.forceApprove(call.user, call.asset.amount);
+ IERC20(call.asset.token).safeTransferFrom(msg.sender, address(this), call.asset.amount);
+ IERC20(call.asset.token).forceApprove(call.user, call.asset.amount);
}
}
@@ -164,7 +164,7 @@ contract XAccount {
}
function _fundUser(CallByUser memory call) internal {
- call.asset.token.safeTransferFrom(msg.sender, call.user, call.asset.amount);
+ IERC20(call.asset.token).safeTransferFrom(msg.sender, call.user, call.asset.amount);
}
// Used if the caller is trying to unwrap the native token to this contract.
diff --git a/src/ERC7683Permit2Lib.sol b/src/ERC7683Permit2Lib.sol
new file mode 100644
index 0000000..2f25c44
--- /dev/null
+++ b/src/ERC7683Permit2Lib.sol
@@ -0,0 +1,72 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.0;
+
+import "./OriginSettler.sol";
+import "./DestinationSettler.sol";
+import "./IPermit2.sol";
+import {GaslessCrossChainOrder} from "./ERC7683.sol";
+
+bytes constant CALL_BY_USER_TYPE = abi.encodePacked(
+ "CallByUser(", "address user,", "Asset asset,", "uint64 chainId,", "bytes32 delegateCodeHash,", "Call[] calls)"
+);
+
+bytes constant CALL_TYPE = abi.encodePacked("Call(", "address target,", "bytes callData,", "uint256 value)");
+
+bytes constant ASSET_TYPE = abi.encodePacked("Asset(", "address token,", "uint256 amount)");
+
+bytes32 constant CALL_BY_USER_TYPE_HASH = keccak256(CALL_BY_USER_TYPE);
+
+library ERC7683Permit2Lib {
+ bytes internal constant GASLESS_CROSS_CHAIN_ORDER_TYPE = abi.encodePacked(
+ "GaslessCrossChainOrder(",
+ "address originSettler,",
+ "address user,",
+ "uint256 nonce,",
+ "uint256 originChainId,",
+ "uint32 openDeadline,",
+ "uint32 fillDeadline,",
+ "bytes32 orderDataType,",
+ "CallByUser orderData)"
+ );
+
+ bytes internal constant GASLESS_CROSS_CHAIN_ORDER_EIP712_TYPE =
+ abi.encodePacked(GASLESS_CROSS_CHAIN_ORDER_TYPE, CALL_BY_USER_TYPE, CALL_TYPE, ASSET_TYPE);
+ bytes32 internal constant GASLESS_CROSS_CHAIN_ORDER_TYPE_HASH = keccak256(GASLESS_CROSS_CHAIN_ORDER_EIP712_TYPE);
+
+ string private constant TOKEN_PERMISSIONS_TYPE = "TokenPermissions(address token,uint256 amount)";
+ string internal constant PERMIT2_ORDER_TYPE = string(
+ abi.encodePacked(
+ "GaslessCrossChainOrder witness)", CALL_BY_USER_TYPE, GASLESS_CROSS_CHAIN_ORDER_TYPE, TOKEN_PERMISSIONS_TYPE
+ )
+ );
+
+ // Hashes an order to get an order hash. Needed for permit2.
+ function hashOrder(GaslessCrossChainOrder memory order, bytes32 orderDataHash) internal pure returns (bytes32) {
+ return keccak256(
+ abi.encode(
+ GASLESS_CROSS_CHAIN_ORDER_TYPE_HASH,
+ order.originSettler,
+ order.user,
+ order.nonce,
+ order.originChainId,
+ order.openDeadline,
+ order.fillDeadline,
+ order.orderDataType,
+ orderDataHash
+ )
+ );
+ }
+
+ function hashUserCallData(CallByUser memory userCallData) internal pure returns (bytes32) {
+ return keccak256(
+ abi.encode(
+ CALL_BY_USER_TYPE_HASH,
+ userCallData.user,
+ userCallData.asset,
+ userCallData.chainId,
+ userCallData.delegateCodeHash,
+ userCallData.calls
+ )
+ );
+ }
+}
diff --git a/src/IPermit2.sol b/src/IPermit2.sol
new file mode 100644
index 0000000..61df041
--- /dev/null
+++ b/src/IPermit2.sol
@@ -0,0 +1,30 @@
+pragma solidity ^0.8.0;
+
+interface IPermit2 {
+ struct TokenPermissions {
+ address token;
+ uint256 amount;
+ }
+
+ struct PermitTransferFrom {
+ TokenPermissions permitted;
+ uint256 nonce;
+ uint256 deadline;
+ }
+
+ struct SignatureTransferDetails {
+ address to;
+ uint256 requestedAmount;
+ }
+
+ function permitWitnessTransferFrom(
+ PermitTransferFrom memory permit,
+ SignatureTransferDetails calldata transferDetails,
+ address owner,
+ bytes32 witness,
+ string calldata witnessTypeString,
+ bytes calldata signature
+ ) external;
+
+ function transferFrom(address from, address to, uint160 amount, address token) external;
+}
diff --git a/src/OriginSettler.sol b/src/OriginSettler.sol
index e0bda1a..6a45eba 100644
--- a/src/OriginSettler.sol
+++ b/src/OriginSettler.sol
@@ -4,10 +4,14 @@ import {SafeERC20} from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol
import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import {GaslessCrossChainOrder, ResolvedCrossChainOrder, IOriginSettler, Output, FillInstruction} from "./ERC7683.sol";
import {CallByUser, Call, Asset} from "./DestinationSettler.sol";
+import "./IPermit2.sol";
+import "./ERC7683Permit2Lib.sol";
contract OriginSettler {
using SafeERC20 for IERC20;
+ IPermit2 public immutable PERMIT2 = IPermit2(address(0xf00d));
+
// codeAddress will be set as the user's `code` on the `chainId` chain.
struct Authorization {
uint256 chainId;
@@ -20,11 +24,6 @@ contract OriginSettler {
Authorization[] authlist;
}
- struct InputAsset {
- IERC20 token;
- uint256 amount;
- }
-
error WrongSettlementContract();
error WrongChainId();
error WrongOrderDataType();
@@ -35,16 +34,18 @@ contract OriginSettler {
function openFor(GaslessCrossChainOrder calldata order, bytes calldata signature, bytes calldata originFillerData)
external
{
+ // TODO: Do we need to verify that signature is the signed order so that the filler can't just pass in any
+ // order data here? Or will this be implicitly handled by passing the signature into _processPermit2Order?
(
ResolvedCrossChainOrder memory resolvedOrder,
CallByUser memory calls,
EIP7702AuthData memory authData,
- InputAsset memory inputAsset
+ Asset memory inputAsset
) = _resolveFor(order, originFillerData);
// TODO: Support permit2 or approve+transferFrom flow or something else?
// // Verify Permit2 signature and pull user funds into this contract
- // _processPermit2Order(order, acrossOrderData, signature);
+ _processPermit2Order(order, calls, inputAsset, signature);
// TODO: Escrow funds in this contract and release post 7755 proof of settlement? Or use some other
// method.
@@ -53,12 +54,38 @@ contract OriginSettler {
emit IOriginSettler.Open(keccak256(resolvedOrder.fillInstructions[0].originData), resolvedOrder);
}
+ function _processPermit2Order(
+ GaslessCrossChainOrder memory order,
+ CallByUser memory calls,
+ Asset memory inputAsset,
+ bytes memory signature
+ ) internal {
+ IPermit2.PermitTransferFrom memory permit = IPermit2.PermitTransferFrom({
+ permitted: IPermit2.TokenPermissions({token: inputAsset.token, amount: inputAsset.amount}),
+ nonce: order.nonce,
+ deadline: order.openDeadline
+ });
+
+ IPermit2.SignatureTransferDetails memory signatureTransferDetails =
+ IPermit2.SignatureTransferDetails({to: address(this), requestedAmount: inputAsset.amount});
+
+ // Pull user funds.
+ PERMIT2.permitWitnessTransferFrom(
+ permit,
+ signatureTransferDetails,
+ order.user,
+ ERC7683Permit2Lib.hashOrder(order, ERC7683Permit2Lib.hashUserCallData(calls)), // witness data hash
+ ERC7683Permit2Lib.PERMIT2_ORDER_TYPE, // witness data type string
+ signature
+ );
+ }
+
function decode(bytes memory orderData)
public
pure
- returns (CallByUser memory calls, EIP7702AuthData memory authData, InputAsset memory asset)
+ returns (CallByUser memory calls, EIP7702AuthData memory authData, Asset memory asset)
{
- return (abi.decode(orderData, (CallByUser, EIP7702AuthData, InputAsset)));
+ return (abi.decode(orderData, (CallByUser, EIP7702AuthData, Asset)));
}
function _resolveFor(GaslessCrossChainOrder calldata order, bytes calldata fillerData)
@@ -68,7 +95,7 @@ contract OriginSettler {
ResolvedCrossChainOrder memory resolvedOrder,
CallByUser memory calls,
EIP7702AuthData memory authData,
- InputAsset memory inputAsset
+ Asset memory inputAsset
)
{
if (order.originSettler != address(this)) {
@@ -89,7 +116,7 @@ contract OriginSettler {
// Max outputs that filler should spend on destination chain.
Output[] memory maxSpent = new Output[](1);
maxSpent[0] = Output({
- token: _toBytes32(address(calls.asset.token)),
+ token: _toBytes32(calls.asset.token),
amount: calls.asset.amount,
recipient: _toBytes32(calls.user),
chainId: calls.chainId
@@ -98,7 +125,7 @@ contract OriginSettler {
// Minimum outputs that must be pulled from caller on this chain.
Output[] memory minReceived = new Output[](1);
minReceived[0] = Output({
- token: _toBytes32(address(inputAsset.token)),
+ token: _toBytes32(inputAsset.token),
amount: inputAsset.amount,
recipient: _toBytes32(msg.sender), // We assume that msg.sender is filler and wants to be repaid on this chain.
chainId: block.chainid
diff --git a/test/Counter.t.sol b/test/Counter.t.sol
deleted file mode 100644
index 54b724f..0000000
--- a/test/Counter.t.sol
+++ /dev/null
@@ -1,24 +0,0 @@
-// SPDX-License-Identifier: UNLICENSED
-pragma solidity ^0.8.13;
-
-import {Test, console} from "forge-std/Test.sol";
-import {Counter} from "../src/Counter.sol";
-
-contract CounterTest is Test {
- Counter public counter;
-
- function setUp() public {
- counter = new Counter();
- counter.setNumber(0);
- }
-
- function test_Increment() public {
- counter.increment();
- assertEq(counter.number(), 1);
- }
-
- function testFuzz_SetNumber(uint256 x) public {
- counter.setNumber(x);
- assertEq(counter.number(), x);
- }
-}