Last Week: Finalized the blog post on succinctness (pending version 19.4 pointer update); updated documentation to correct factual errors and remove memory-hard mining references; reviewed the epsilon pull request regarding the sliding window bloom filter and guesser knowledge requirements; and developed a local libP2P pull request to resolve packet size and nested relay issues causing syncing nodes to drop connections.
Coming Week: Rebase the libP2P pull request and push code to GitHub; publish the succinctness blog post after updating the pointer to version 19.4; prioritize discussion with Thorkil regarding guesser reveal data and archival mutator set requirements.
Thorkil Værge
Last Week: Fixed low and medium severity security issues (transaction upgrader abuses, peer panics from skipped validation steps, and unmigrated libP2P flags); released version 19.3 for efficient archival mutator set sharing; implemented raw LevelDB database interfaces transmitting only raw leaves (reducing sharing time to under 50 ms and size to 40 MB); added multi-threaded Tip5 proof-of-work puzzle requirements and ban penalties for archival mutator requesters; modified handshake protocol extra data fields for transaction relay and archival mutator sharing preferences; and collaborated on the succinct validation rollout strategy and grandparent mutator set updates to prevent hidden block attacks.
Coming Week: Coordinate follow-up meetings asynchronously; continue advancing the succinct validation rollout and soft fork implementations.
3. Technical Discussion
Archival Mutator Set Sharing & Version 19.3: Version 19.3 was released to share archival mutator sets efficiently. By utilizing raw LevelDB database interfaces instead of persisted list abstractions, data transfer was reduced to under 50 milliseconds and 40 megabytes by sending only raw leaves and key/value bytes. Requesters must solve a multi-threaded standard Tip5 proof-of-work puzzle with a difficulty in the tens of millions and are subject to a 3-day ban penalty to prevent repeat requests.
Handshake Protocol Modifications: Handshake extra data fields in version 19.3 were modified to consume two characters: one indicating whether peers want to relay transactions (blocks-only field), and another communicating refusal to serve the archival mutator set along with the demanded proof-of-work difficulty.
Succinct Validation (S1) & Hidden Block Attack Mitigation: Addressed the hidden block attack vector where data is hidden in blocks needed by unspent transaction output owners to update membership proofs. Rule 2V (requiring guessers to demonstrate knowledge of the archival mutator set) was deferred for the initial S1 rollout to avoid locking in regrettable changes. Validation updates are split into two separate soft forks: binding power data and adding a self-recursive appendix. Grandparent mutator set updates will be sent separately in an appendix to prevent attackers from continuing on bad or solo chains without impacting block size limits or transaction throughput.
libP2P Network Discovery: Investigated and resolved packet size issues caused by nested relays at arbitrary depths in bootstrapper node data, preventing syncing nodes from dropping connections. Classified as a non-vulnerability optimization, with changes kept local pending rebasing.
4. Updates and Announcements
Released version 19.3 to enable efficient archival mutator set sharing.