HD Node

Wraps an Ethereum node RPC endpoint with account managment.

This allows, for example, to run a local node RPC endpoint that proxies all requests to say, Infura, while internally handing account-specific requests like eth_sendTransaction.

Validation

The service provides some very basic validation on the signed data:

1. The chain ID specified in the transaction and typed data must match the node's chain ID
2. The nonce specified in the transaction is only the next nonce. This means you can only sign one transaction at a time, but is important for foward secrecy.

Additionally, the service has a concept of a "validator" - a Lua module that gets called on every signature operation to validate whether or not the signature should be allowed. It can perform arbitrary logic. For an example, take a look at the CowSwap sample validator.

TODO

• CI
• Increase test coverage - its pretty poor ATM
• Optionally record signatures to a database instead of just logging them
• General project cleanup - it was done quite quickly