Decode 0x3593564c execute function

[jazzlifepro]

Ethers Version

6.13.2

Search Terms

abi, execute function, 0x3593564c, decode

Describe the Problem

I'm trying to decode parameter data in a swap transaction that uses function "0x3593564c execute" occurred on BSC TestNet to extract all the information they contain.
The ABI is 'function execute(bytes calldata param1, bytes[] calldata param2, uint256 param3)'.
Here is an example of the data that can be seen in the transaction details, in the Input Data field:"
https://testnet.bscscan.com/tx/0xaa4eca5c9fbc195238fd2a5158e424cb899020f45dba0a8791963bded6ca4e4e
0 | commands | bytes | 0x0b00
1 | inputs | bytes[] |
0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000
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
2 | deadline | uint256 | 1724064461

Param1: Commands
Param2: Unknown
Param3: Timestamp

I was searching on the internet for the param2 encoding format of this function but I couldn't find anything.

I've been trying various functions in ethers.js to decode this array of data, but none of them work without knowing its structure beforehand.

Code Snippet

No response

Contract ABI

'function execute(bytes calldata param1, bytes[] calldata param2, uint256 param3)'

Errors

No response

Environment

node.js (v12 or newer)

Environment (Other)

No response

[ricmoo]

Can you include the error you are getting? Also, what is the ABI used to encode the param2. If you want to decode the bytes, you need to know what format is used to encode it. If you have a link to the tx on block explorer, that'd be helpful too. :)

Few quick notes:

• the data (inputs) is 321 bytes long, which seems odd, since it should be a multiple of 32
• no selector is present, so decoding will require using the low-level decode operations since the high-level API expects calldata.

(chatted on Discord; the OP will update the issue shortly)

[jazzlifepro]

Can you include the error you are getting? Also, what is the ABI used to encode the param2. If you want to decode the bytes, you need to know what format is used to encode it. If you have a link to the tx on block explorer, that'd be helpful too. :)

Few quick notes:

• the data (inputs) is 321 bytes long, which seems odd, since it should be a multiple of 32
• no selector is present, so decoding will require using the low-level decode operations since the high-level API expects calldata.

(chatted on Discord; the OP will update the issue shortly)

I already updated the issue.

[ricmoo]

Sorry for the delay. Here is a complete working example, which should help:

import { ethers } from "./test.js";


(async function() {
  const hash = "0xaa4eca5c9fbc195238fd2a5158e424cb899020f45dba0a8791963bded6ca4e4e";

  // Connect to BNB testnet
  const provider = ethers.getDefaultProvider("bnbt");

  // Get the transaction from the network
  const tx = await provider.getTransaction(hash);

  // The minimal ABI needed for parsing
  const iface = new ethers.Interface([
    "function execute(bytes command, bytes[] inputs, uint deadline)"
  ]);

  // Parse the transaction; this will include a .args property
  const result = iface.parseTransaction(tx);
  console.log(result);
  // TransactionDescription {
  //   name: 'execute',
  //   args: Result(3) [
  //     '0x0b00',
  //     Result(2) [
  //       '0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000',
  //       '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'
  //     ],
  //     1724064461n
  //   ],
  //   signature: 'execute(bytes,bytes[],uint256)',
  //   selector: '0x3593564c',
  //   value: 100000000000000n
  // }

  const { command, inputs, deadline } = result.args;
  console.log({ command, inputs, deadline });
  // {
  //   command: '0x0b00',
  //   inputs: Result(2) [
  //     '0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000',
  //     '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'
  //   ],
  //   deadline: 1724064461n
  // }
})();

Let me know if anything needs further explanation. :)

(I'll move this from issues to discussions)

[jazzlifepro]

I honestly don't understand what you're trying to show me. In what part of the code does parameter 2 decode? I don't see it
Besides, it is asking the same query 2 times in different ways.
This is the log:

TransactionDescription {
fragment: FunctionFragment {
type: 'function',
inputs: [ [ParamType], [ParamType], [ParamType] ],
name: 'execute',
constant: false,
outputs: [],
stateMutability: 'nonpayable',
payable: false,
gas: null
},
name: 'execute',
args: Result(3) [
'0x0b00',
Result(2) [
'0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000',
'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'
],
1724064461n
],
signature: 'execute(bytes,bytes[],uint256)',
selector: '0x3593564c',
value: 100000000000000n
}
{
command: '0x0b00',
inputs: Result(2) [
'0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000',
'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'
],
deadline: 1724064461n
}

I need to decode this parameter to obtain the wallets involved, amount of tokens sent, etc. and then send a transaction filling this parameter with new encoded data.

[jazzlifepro]

Looking at the code and documentation of PancakeSwap, I found this:

Parameter 1 corresponds to the commands that will be executed in Parameter 2. In my case, 0x0b00 would be:
WRAP_ETH (0x0b) (address recipient, uint256 amountMin)
V3_SWAP_EXACT_IN (0x00) (address recipient, uint256 amountIn, uint256 amountOutMin, bytes path, bool payerIsUser).

Parameter 2 is an array of byte strings. Each element in the array is the ABI-encoded input that will be used for the respective command. Each command is identified by a byte (bytes1), and depending on the value of that byte, the corresponding input is decoded using abi.decode or Solidity assembly.

The issue is that I want to decode this in Python or Node, but the results I'm getting don't make sense.

With Python:
python inputdata2.py
WRAP_ETH
Recipient: 0x0000000000000000000000000000000000000002
Amount Min: 100000000000000
V3_SWAP_EXACT_IN
Recipient: 0xa9e4c77d44267F7F48f96c67faBEE55783c6e1A4,
Amount In: 100000000000000,
Amount Out Min: 1861818621027981,
Path: 0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000002bae13d989dac2f0debff460ac112a837c89baa7cd0009c4ed24fc36d5ee211ea25a80239fb8c4cfd80f12ee000000000000000000000000000000000000000000,
Payer Is User: False

This is the data I am getting. They don't make much sense.

[ricmoo]

Can you link to the documentation where you get the ABI format to decode the param2 fields?

[jazzlifepro]

https://testnet.bscscan.com/address/0xd77c2afebf3dc665af07588bf798bd938968c72e#code
https://docs.uniswap.org/contracts/universal-router/technical-reference

[ricmoo]

Here is a short example script to decode what I think you are trying to accomplish:

const Fields = {
  "0b": [
    "address recipient",
    "uint256 amount"
  ],
  "00": [
    "address recipient",
    "uint256 amountIn",
    "uint256 amountOutMin",
    "bytes path",
    "bool payerIsUser"
  ],
};

function decode(command, data) {
  const fields = Fields[command];
  return {
      command,
      result: ethers.AbiCoder.defaultAbiCoder().decode(fields, data)
  }
}

const commands = '0x0b00';

const params2 = [
  '0x000000000000000000000000000000000000000000000000000000000000000200000000000000000000000000000000000000000000000000005af3107a4000',
  '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'
];

for (let i = 0; i < params2.length; i++) {
  const command = commands.substring(2 + (i * 2), 2 + ((i + 1) * 2));
  console.log(decode(command, params2[i]));
}

Which produces the following output:

{
  command: '0b',
  result: Result(2) [
    '0x0000000000000000000000000000000000000002',
    100000000000000n
  ]
}
{
  command: '00',
  result: Result(5) [
    '0xa9e4c77d44267F7F48f96c67faBEE55783c6e1A4',
    100000000000000n,
    1861818621027981n,
    '0xae13d989dac2f0debff460ac112a837c89baa7cd0009c4ed24fc36d5ee211ea25a80239fb8c4cfd80f12ee',
    false
  ]
}

Is that what you were looking for?

[jazzlifepro]

That's right. It's the same result I got.

If we compare with the transaction details, the recipient matches, the amountIn matches (100000000000000 wei = 0.0001 ETH/TBNB), but the amountOutMin does not match. It should be 0.002475978857485536 BUSD. Why is this happening?

[jazzlifepro]

I already understood that it does not match because the result in amountOutMin is the minimum number of tokens that are expected to be received based on the slippage.

[ricmoo]

So is everything sorted then? Or are there still curiosities? :)