eth2 quick update number 3

Welcome to the third article. eth2 quick update.

tldr;

• Strengthening fork selection defenses in response to audits
• introduction challenges.ethereum.org
• Herumi grant for ultrafast BLS implementation

fork selection defense

This week we strengthened our defense of the level 0 fork selection rule. We spend a lot of time analyzing eth2 to ensure that the system can remain stable even under adverse conditions (e.g. large-scale attackers, major network outages or partitions, etc.). The goal of any large engineering project is to find as many potential problems and prepare for these scenarios before launch. That is why we have been working with many external teams and researchers to conduct audits, economic analyzes and formal verification of eth2. But at the same time, as we move toward launch, we must remain vigilant and flexible to respond to unexpected attacks during production. (Example: Shanghai DoS attack in 2016)

To help with this effort, consensus researcher Ryuya Nakamura analyzed eth2’s consensus algorithm (Casper FFG) and fork selection rule (LMD GHOST) to better determine how these two parts of the protocol could be utilized in some scenarios. He has many great articles, including: ethresearch.ch Some attack vectors and recommended solutions are discussed in detail. Please confirm Decoy flip-flop attack on LMD GHOST, Bound attack analysis for FFGand Preventing boundary attacks on FFG For informative and entertaining reading.

Fortunately, the recommended solutions for decoy flip-flop and bouncing attacks are all simple modifications to the fork options in stage 0. Decoy flip-flop attacks are solved by considering only validator proofs from the current and previous epochs when: adding Proof of the fork selection point of view. You can see PR changing the specs. here. Bounce attacks are solved by updating only the most recently justified checkpoint within the first fork selection. K Slots of the ages. later K For slots, we postpone the inclusion of new legitimate checkpoints in fork selection until the next epoch boundary. You can check this fix here.

Several other components of the Phase 0 specification are not currently subject to audit. While we do not expect any major changes, we do anticipate a small number of additional post-audit proposed changes that will be implemented for PR in the coming months.

challenges.ethereum.org

Just released challenges.ethereum.org. This site is your single source for all current bounties hosted by the Ethereum Foundation or related to Ethereum research and development. Bounties range from finding vulnerabilities in existing Ethereum infrastructure to finding collisions in new hash functions. Something for everyone 🙂

We’ll continue to build out EF’s bounties program in the coming months, so check back for more opportunities.

Herumi BLS Grant

The grant was given to Shigeo Mitsunari, manager of the ultra-fast Herumi. pairing library and BLS Signature Library. This grant will support new BLS standards (New Hash-G2It helps to do things like constant-time signing, etc.) as well as some more practical stuff for eth2 usability (Rust integration, fuzzing operations, etc.).

In addition to the functional component of the grant, there is also a performance component. The Herumi library is already 2-3 times faster than the suboptimal BLS option, but since signature verification is one of the main bottlenecks of eth2, the additional gain here is outstanding, allowing eth2 to run under much higher loads and more adverse scenarios. . Shigeo will invest additional time and effort into optimizing your libraries to ensure they run properly. ASAP 🚀.