cannot unmarshal hex number with leading zero digits into Go struct field TransactionArgs.authorizationList.s

[fubuloubu]

I am submitting a transaction to geth --dev containing an authorizationList with an item that has this for the s parameter: 0x0ef6776606b8edf07d5fe7f4d10ddecaeafdcfaa24dc81e23376147a1e8a4519

System information

Geth version: 1.15.11-stable-36b2371c
CL client & version: n/a
OS & Version: Linux
Commit hash : n/a

Expected behaviour

Transaction success

Actual behaviour

Transaction raises with:

invalid argument 0: json: cannot unmarshal hex number with leading zero digits into Go struct field TransactionArgs.authorizationList.s of type *uint256.Int

Steps to reproduce the behaviour

Do not have this

Backtrace

Do not have this

[fjl]

Which client are you using to submit the transaction?

[fubuloubu]

Which client are you using to submit the transaction?

web3py

[fjl]

It is the expected behavior. The s value is defined as uint256 in the spec, and does not allow specifying leading zero bytes. https://github.com/ethereum/execution-apis/blob/de87e24e0f2fbdbaee0fa36ab61b8ec25d3013d0/src/schemas/transaction.yaml#L82-L84

So web3py is encoding it incorrectly.

[fjl]

I checked, and it uses HexBytes, which is wrong. So you need to bring it up with them to change the encoding.

https://github.com/ethereum/web3.py/blob/0daa470f9bd7f3eaf0316684f2eaa8fdcb24bb43/web3/types.py#L106

[fubuloubu]

It is the expected behavior. The s value is defined as uint256 in the spec, and does not allow specifying leading zero bytes. https://github.com/ethereum/execution-apis/blob/de87e24e0f2fbdbaee0fa36ab61b8ec25d3013d0/src/schemas/transaction.yaml#L82-L84

So web3py is encoding it incorrectly.

Is the issue the inclusion of 0x? Because 0e is nonzero, so that would be confusing to me why it raises "leading zero" on a nonzero byte (and also this works perfectly fine with anvil)

[fjl]

The issue is that numbers are not supposed to include leading zero in text. The 0x is the hex prefix and it's required. So this error is about the 0e byte.

See here for the regular expression pattern that is expected for uint256: https://github.com/ethereum/execution-apis/blob/de87e24e0f2fbdbaee0fa36ab61b8ec25d3013d0/src/schemas/base-types.yaml#L62

[fjl]

Note also the error message says "leading zero digits". I was a bit imprecise talking about leading zero byte in my earlier comment.

[fubuloubu]

The issue is that numbers are not supposed to include leading zero in text. The 0x is the hex prefix and it's required. So this error is about the 0e byte.

See here for the regular expression pattern that is expected for uint256: https://github.com/ethereum/execution-apis/blob/de87e24e0f2fbdbaee0fa36ab61b8ec25d3013d0/src/schemas/base-types.yaml#L62

That's weird it requires odd-length hex strings, but who am I to question production code lol

I reported it downstream to web3py to fix. Thank you for helping me pin down the issue