Grasshopper
Ban resistance by continuously moving a contract through the address space. The implemented PoC is a mixer that cannot be banned through static list techniques.
Created on 18th September 2022
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Grasshopper
Ban resistance by continuously moving a contract through the address space. The implemented PoC is a mixer that cannot be banned through static list techniques.
The problem Grasshopper solves
Grasshopper addresses are more difficult to idenitfy and ban through static list techniques as was witnessed recently with Tornado cash. Banning techniques can only identify previous and current locations, but not future locations which can be created upon each and every user interact, making Grasshoppers an ever moving target. Additionally, it has a UI that can easily allow a user to find the latest contract by following a chain of transactions and movements since the last known good address.
Challenges I ran into
Due to the removal of Tornado Cash repositories, and incomplete deployment of clones, generating necessary elements to test against Tornado Cash was not possible during the Hackathon.
We decided to use a simple ringsignature based mixer to demonstrate a Grasshopper implementation in a use case resembling that of Tornado, albeit with considerably lower privacy. We struggled with the scripts to generate the cryptographic proofs necessary for withdrawals which reduced the amount of time allowed to testing
Technologies used