Ethereum JSON-RPC: signatures -- validate value of V

[raulk]

V corresponds to the public key recovery coordinates selector for the ECDSA signature on the elliptic curve function. See https://bitcoin.stackexchange.com/questions/38351/ecdsa-v-r-s-what-is-v. There are only some values possible in Ethereum, and I think they might have even changed over time (but I'm not sure if this was Ethereum or Bitcoin).

Whoever takes this issue should check:

1. Which V values are legal in Ethereum.
2. That we validate that only legal values are used in signatures received through the Eth JSON-RPC eth_sendRawTransaction operation.

[maciejwitowski]

@raulk can you set milestone and priority? Thanks!

[raulk]

@ychiaoli18 description added.

[raulk]

Merged in filecoin-project/lotus#9970.