This PR mitigates an issue with Ledger's on-device RLP deserialization, see
https://github.com/LedgerHQ/app-ethereum/issues/409
Ledger's RLP deserialization code does not validate the length of the RLP list received,
and it may prematurely enter the signing flow when a APDU chunk boundary falls immediately
before the EIP-155 chain_id when deserializing a transaction. Since the chain_id is
uninitialized, it is 0 during this signing flow. This may cause the user to accidentally
sign the transaction with chain_id = 0. That signature would be returned from the device 1
packet earlier than expected by the communication loop. The device blocks the
second-to-last packet waiting for the signer flow, and then errors on the successive
packet (which contains the chain_id, zeroed r, and zeroed s)
Since the signature's early arrival causes successive errors during the communication
process, geth does not parse the improper signature produced by the device, and therefore
no improperly-signed transaction can be created. User funds are not at risk.
We mitigate by selecting the highest chunk size that leaves at least 4 bytes in the
final chunk.
This changes the CI / release builds to use the latest Go version. It also
upgrades golangci-lint to a newer version compatible with Go 1.19.
In Go 1.19, godoc has gained official support for links and lists. The
syntax for code blocks in doc comments has changed and now requires a
leading tab character. gofmt adapts comments to the new syntax
automatically, so there are a lot of comment re-formatting changes in this
PR. We need to apply the new format in order to pass the CI lint stage with
Go 1.19.
With the linter upgrade, I have decided to disable 'gosec' - it produces
too many false-positive warnings. The 'deadcode' and 'varcheck' linters
have also been removed because golangci-lint warns about them being
unmaintained. 'unused' provides similar coverage and we already have it
enabled, so we don't lose much with this change.