I should be able to locally verify a transaction

[skolliecool]

Hi

I hope I am not misunderstanding anything. After initiating a USDT contract via:

const contract = new ethers.Contract(contractAddress, contractAbiFragment, signer);

I get back the following:

{
  "hash": "0xf4584008cc70f2f532765a2f035a2525992a258b2d2afd6b49ad5b2857a6197d",
  "type": 2,
  "accessList": null,
  "blockHash": null,
  "blockNumber": null,
  "transactionIndex": null,
  "confirmations": 0,
  "from": "0x0936c90c59ecb79fc01C780f283CABfB9e118940",
  "gasPrice": {
    "_hex": "0x203f403384",
    "_isBigNumber": true
  },
  "gasLimit": {
    "_hex": "0xb41d",
    "_isBigNumber": true
  },
  "to": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
  "value": {
    "_hex": "0x00",
    "_isBigNumber": true
  },
  "nonce": 38,
  "data": "0xa9059cbb0000000000000000000000009418bfc542817e4320480990f34951351b0db5130000000000000000000000000000000000000000000000000000000002faf080",
  "r": "0x270e826d5bbf71fa492de0da460b06f0f586d007d05db364493d1bf70b4fc77e",
  "s": "0x4b4795d7c50cd4e56342ab3044cb3986f85278a4a2377dcc621589d8289bfaaf",
  "v": 1,
  "creates": null,
  "chainId": 0
}

Now, I should have everything to locally verify this transaction:

1. I should be able to rehash the transaction, and compare that hash with the above hash.
2. Then, I should be able to use the signature (r,s,v) to enure that nothing has been altered.

Why am I unable to do this easily in ethers? I suspect it is because I am missing information? If so, what?

[ricmoo]

Everything you should need is there. Can you include the code you are using and how you are computing the transaction pre-image for the digest computation?

For more details on how to compute a transaction hash, see: https://github.com/ethers-io/ethers.js/blob/master/packages/transactions/src.ts/index.ts

[ricmoo]

(moving to discussions)

[skolliecool]

This is what I am doing:

Sending Transaction

const contractAbiFragment = [
  // Some details about the token
  "function name() view returns (string)",
  "function symbol() view returns (string)",

  // Get the account balance
  "function balanceOf(address) view returns (uint)",

  // Send some of your tokens to someone else
  "function transfer(address to, uint amount)",
]
const contractAddress =  "0xdAC17F958D2ee523a2206206994597C13D831ec7"; // USDT contract
const signer = ...; // The metamask signer
const contract = new ethers.Contract(contractAddress, contractAbiFragment, signer);
const tx = await contract.transfer(strategyWalletAddress, numberOfTokens);

The result I get is this:

{
  "hash": "0xf4584008cc70f2f532765a2f035a2525992a258b2d2afd6b49ad5b2857a6197d",
  "type": 2,
  "accessList": null,
  "blockHash": null,
  "blockNumber": null,
  "transactionIndex": null,
  "confirmations": 0,
  "from": "0x0936c90c59ecb79fc01C780f283CABfB9e118940",
  "gasPrice": {
    "_hex": "0x203f403384",
    "_isBigNumber": true
  },
  "gasLimit": {
    "_hex": "0xb41d",
    "_isBigNumber": true
  },
  "to": "0xdAC17F958D2ee523a2206206994597C13D831ec7",
  "value": {
    "_hex": "0x00",
    "_isBigNumber": true
  },
  "nonce": 38,
  "data": "0xa9059cbb0000000000000000000000009418bfc542817e4320480990f34951351b0db5130000000000000000000000000000000000000000000000000000000002faf080",
  "r": "0x270e826d5bbf71fa492de0da460b06f0f586d007d05db364493d1bf70b4fc77e",
  "s": "0x4b4795d7c50cd4e56342ab3044cb3986f85278a4a2377dcc621589d8289bfaaf",
  "v": 1,
  "creates": null,
  "chainId": 0
}

So, I would want to use utils.parseTransaction, only I would need to serialize the above transaction. This is a problem because when I try to serialize the above transaction, I get Error: mismatch EIP-1559 gasPrice != maxFeePerGas...

So I assume I cannot use utils.parseTransaction. So how would I go about it:

1. Create a hash as shown, and then compare with the txHash above?
2. Verifying with a signature? How would I do that with the r,s,v above?

[skolliecool]

So be certain, I just tried to use parseTransaction. But I assume there is no easy way out and I will need to do this manually?

[skolliecool]

@ricmoo Here is the code that I am trying to use to verify the above transaction:

const rawTransaction = getRawTransaction(tx); // getRawTransaction is from the cookbook - this throws an error as tx.hash does not equal the calculated hash.
const transaction = utils.parseTransaction(rawTransaction); 

My understanding is that how it was done. Is this incorrect?