ABI encoding address checksum validation

[Gudahtt]

I would like to use the AbiCoder to encode addresses that are not valid EIP-55 checksums. However, AbiCoder doesn't seem to allow this at the moment. It will automatically validate that any mixed-case address values are valid address checksums according to EIP-55.

This is problematic for me because I'm trying to replace the use of ethereumjs-abi with minimal breaking changes, and ethereumjs-abi has no such validation. If I were to accept this requirement that address data must be valid EIP-55 checksums, it would break compatibility with anything that used non-EIP-55 mixed-case address data.

Even if it were feasible for us to accept this validation, I'm not sure we'd want to. There are legitimate reasons for wanting to use mixed-case addresses that are not valid address checksums according to EIP-55. For example, address checksums created according to EIP-1191 are currently considered as invalid by the AbiCoder. As such, this validation seems overly restrictive.

[Gudahtt]

Nevermind - I can just normalize the input prior to passing it into the encoder! I was misunderstanding how this was being encoded. False alarm.

As a matter of API convenience, it might still be worth considering dropping this validation so that those using EIP-1191 can use the AbiCoder without the extra step though.

[ricmoo]

Thanks for letting me know of this EIP, I have added my comments.

As I understand it, this EIP would effectively abolish the usefulness of checksum addresses, but I’m waiting on some feedback before I get too crazy rallying against it. :)

As it stands now though, if I understand the EIP (and sentiment on the discussions) this would never be incorporated into ethers, sorta for the exact problem you are having. :)

It is possible in v6 to override this in the network formatter, but I’ll worry about that if this EIP gains adoption. :)

[juli]

Checksums should be used in user facing code only: showing checksumed addresses that users can copy&paste, and validating user input. As soon as you validate user input you should normalize the address to pass it to libaries.