[General] Cannot use 2 or more parameters in the paymaster's innerInput data

[lutr0]

Environment

Testnet

Provide a brief description of the functionality you're trying to implement.

I am trying to deploy a custom paymaster implementation that verify a second signature by passing data to the innerInput.

What is the specific issue or error you're encountering?

I can pass one parameter (e.g. the expiration timestamp), but I receive the error below if I try to add more

Can you share the error messages or logs you're receiving, if any?

1 failing

  1) ERC20Paymaster
       Should validate and pay for paymaster transaction:
     Error: processing response error (body="{\"jsonrpc\":\"2.0\",\"error\":{\"code\":3,\"message\":\"Execution error: Failed to execute next transaction: Paymaster validation error: Error function_selector = 0x, data = 0x\",\"data\":\"0xf92b35b5d25a58b78e93049a6d71aa6917bb24c2c38062a5b9ed55b1d26b34ed\"},\"id\":64}\n", error={"code":3,"data":"0xf92b35b5d25a58b78e93049a6d71aa6917bb24c2c38062a5b9ed55b1d26b34ed"}, requestBody="{\"method\":\"eth_sendRawTransaction\",\"params\":[\"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\"],\"id\":64,\"jsonrpc\":\"2.0\"}", requestMethod="POST", url="http://localhost:8011", code=SERVER_ERROR, version=web/5.7.1)
      at Logger.makeError (node_modules/@ethersproject/logger/src.ts/index.ts:269:28)
      at Logger.throwError (node_modules/@ethersproject/logger/src.ts/index.ts:281:20)
      at /home/joe/Dev/0Ondefy/ondefy-paymaster/node_modules/@ethersproject/web/src.ts/index.ts:341:28
      at step (node_modules/@ethersproject/web/lib/index.js:33:23)
      at Object.next (node_modules/@ethersproject/web/lib/index.js:14:53)
      at fulfilled (node_modules/@ethersproject/web/lib/index.js:5:58)
      at processTicksAndRejections (node:internal/process/task_queues:95:5)



error Command failed with exit code 1.

Have you made any recent changes to the contract before encountering this issue?

N/A

Are there any external libraries or contracts that your contract interacts with?

No

Can you provide the relevant portions of your contract code where the issue is occurring?

Test file

const innerInput = ethers.utils.solidityPack(["uint256", "bytes"], [expiration, SignedMessageHash]);

    const paymasterParams = utils.getPaymasterParams(
      paymaster.address.toString(),
      {
        type: payType,
        token: token,
        minimalAllowance,
        innerInput: innerInput,
      }
    );

    console.log("Paymaster params: ", paymasterParams);

    await (
      await erc20.connect(userWallet).mint(user.address, 5, {
        maxPriorityFeePerGas: ethers.BigNumber.from(0),
        maxFeePerGas: gasPrice,
        gasLimit: GAS_LIMIT,
        customData: {
          paymasterParams: paymasterParams,
          gasPerPubdata: utils.DEFAULT_GAS_PER_PUBDATA_LIMIT,
        },
      })
    ).wait();
  }

Solidity

if (paymasterInputSelector == IPaymasterFlow.approvalBased.selector) {
          // While the transaction data consists of address, uint256 and bytes data,
          // the data is not needed for this paymaster
          (address token, uint256 amount, bytes memory data) = abi.decode(
              _transaction.paymasterInput[4:],
              (address, uint256, bytes)
          );

          // Unwrap the data
          (uint256 expiration, bytes memory signedMessage) = abi.decode(
              data,
              (uint256, bytes)
          );

Have you tried to isolate the problem, and if so, what were the results?

I tried using different parameters, but I always get an error with 2+ parameters.
It works with only one

What steps have you already taken to try to resolve the issue?

I am running the in-memory node

Repo Link (Optional)

No response

Additional Details

No response

[dutterbutter]

Thanks for posting!! Let me reproduce on my side and I will follow up.

[lutr0]

Hi @dutterbutter, I wonder if this one may also be solved by using arrayifi as in #156.
Still didn't manage to make it work on my end

[dutterbutter]

I havent had a chance to debug this further yet, but I plan to this week. My apologies on the delay. We want to make this apart of the paymaster-examples repo as well so others can see a working example.

[dutterbutter]

Hey @lutr0 - thanks for posting these great questions. Please keep them coming 💪

I was able to pass in two params using the following example:

const value1 = ethers.utils.hexlify(ethers.utils.toUtf8Bytes("dutterbutter"));
const value2 = ethers.utils.hexlify(ethers.utils.toUtf8Bytes("zk_dutterbutter"));

const paymasterParams = utils.getPaymasterParams(
  paymaster.address.toString(),
  {
    type: payType,
    token: token,
    minimalAllowance,
    innerInput: ethers.utils.defaultAbiCoder.encode(
      ["bytes", "bytes"],
      [ethers.utils.arrayify(value1), ethers.utils.arrayify(value2)]
  ),
  }
);

And then on the contract side:

function bytesToString(bytes memory data) internal pure returns (string memory) {
    return string(data);
}

if (paymasterInputSelector == IPaymasterFlow.approvalBased.selector) {
      // While the transaction data consists of address, uint256 and bytes data,
      // the data is not needed for this paymaster
      (address token, uint256 amount, bytes memory data) = abi.decode(
          _transaction.paymasterInput[4:],
          (address, uint256, bytes)
      );

      (string memory strValue1, string memory strValue2) = abi.decode(data, (string, string));
      console.log("value1: ", bytesToString(bytes(strValue1)));
      console.log("value2: ", bytesToString(bytes(strValue2)));

Logs from era-test-node 👇

Note: There is likely optimizations to be done here but figured I would share 💯

[lutr0]

Thank you so much, it's really helpful!
How would it change if a value were a uint256 or an address?