Announcements

Please join us for our next Socratic Seminar. A special thank you to our sponsors CardCoins, Chaincode Labs and ZEBEDEE for food, refreshments and event space.

Mailing Lists, Meetings and Bitcoin Optech

Mailing Lists

bitcoin-dev

• Inherited IDs
• Taproot testnet wallet

lightning-dev

• Full Disclosure: CVE-2021-41591/ CVE-2021-41592 / CVE-2021-41593 “Dust HTLC Exposure Considered Harmful”
• Fast Forwards By Channel-in-Channel Construction, Or: Spillman-Decker-Wattenhofer-Poon-Dryja-Towns
• Lightning over taproot with PTLCs
• A Mobile Lightning User Goes to Pay a Mobile Lightning User
• In-protocol liquidity probing and channel jamming mitigation

Meetings

• Bitcoin PR Review Club
  • 22950 - Pimpl AddrMan to abstract implementation details
  • 23157 - Txmempool -/-> validation 1/2: improve performance of check() and remove dependency on validation
  • 21943 - Dedup and RAII-fy the creation of a copy of CConnman::vNodes
  • 17631 - Expose block filters over REST
  • 22674 - Mempool validation and submission for packages of 1 child + parents
• Bitcoin Core general developer meetings
  • September 30th
  • October 7th
  • October 21st
• Bitcoin Core wallet meetings
  • October 8th
  • October 22nd
• c-lightning meetings
  • September 20th
• dlc-specs meetings
  • October 5th
• Lightning specification meetings
  • October 11th
  • October 25th

Optech

• Newsletter #169
• Newsletter #170
• Newsletter #171
• Newsletter #172

Network Data

• Distribution of Foundry pool across US
• FinCEN links $5.2 billion worth of Bitcoin transactions to ransomware
• Lightning use will outpace capacity growth
• Native segwit outputs continue to increase
• Wallet of Satoshi passes 2 million lightning payments

Research

• Efficient Threshold-Optimal ECDSA
• Elligator Squared for BN-like curves, context
• Evaluating Tooling and Methodology when Analysing Bitcoin Mixing Services After Forensic Seizure
• Fiat–Shamir Bulletproofs are Non-Malleable (in the Algebraic Group Model)
• HD scheme for threshold wallets
• HIDE & SEEK: Privacy-Preserving Rebalancing on Payment Channel Networks
• How to Prove Schnorr Assuming Schnorr: Security of Multi- and Threshold Signatures
• Non-Slanderability of Linkable Spontaneous Anonymous Group Signature (LSAG)
• On the security of ECDSA with additive key derivation and presignatures
• Selfish & Opaque Transaction Ordering in the Bitcoin Blockchain: The Case for Chain Neutrality
• Sleepy Channels: Bitcoin-Compatible Bi-directional Payment Channels without Watchtowers
• Three Attacks on Proof-of-Stake Ethereum
• TopoShot: Uncovering Ethereum’s Network Topology Leveraging Replacement Transactions
• Transaction Fees on a Honeymoon: Ethereum’s EIP-1559 One Month Later
• Verifying Payment Channels with TLA+

InfoSec

• 6,000 Coinbase user accounts accessed by SMS 2FA bypass
• Compound Finance distributes ~$80m in excess COMP rewards, bleeding continues
• Cloned voice leads to $35 million bank heist
• DarkSide ransomware funds flow, more, more
• Facebook nukes DNS A and AAA records for Facebook, Instagram and WhatsApp leading to hours-long outage, causes dns ddos as side effect
• GitKraken dependency ‘keypair’ generates weak SSH keys, Github revokes
• Indexed Finance drained of $16m
• Liquid hard fork diagnostic report
• OpenSea wallets hijacked with malicious NFTs
• Telegram Android image self-destruct bug

Pull Requests and repo updates

Bitcoin Core

• Add Single Random Draw as an additional coin selection algorithm
• Allow UTXO locks to be written to wallet DB
• Add syscall sandboxing using seccomp-bpf (Linux secure computing mode)
• Allow fundrawtransaction and walletcreatefundedpsbt to take external inputs
• Use legacy relaying to download blocks in blocks-only mode
• Add ability to flush keypool and always flush when upgrading non-HD to HD
• Re-include RBF replacement txs in fee estimation
• Make descriptor wallets by default
• Add level 3 verbosity to getblock RPC call

rust-bitcoin

• Taproot P2TR address
• Add OP_CHECKSIGADD and OP_SUCCESSxxx

lnd

• Add postgres
• Allow skipping PsbtFinalize step during channel funding to support external broadcast
• In-memory graph cache for faster pathfinding
• Introduce new commitment format to enforce channel lease expirations in scripts
• lnrpc+peer: custom peer messages
• Support remote signing over RPC
• Channeldb: write through cache for the graph and channel state
• Kvdb: migrate data between different backends

eclair

• Lower minimum remote dust limit
• Configure dust in flight threshold

c-lightning

• Delay fee changes
• Allow sending large HTLCs if peer offers option_support_large_channel (> 4294967295msat)
• Send and support channel_type in channel open
• Removal of old HTLC information and vacuuming shrinks large lightningd.sqlite3 by a factor of 2-3
• Send regular pings to peers to detect dead connections (particularly for Tor)

rust-lightning

• Increase our default/minimum dust limit and decrease our max
• Add channel scoring to get_route

BOLTs

• Peers need to check each other’s dust limit
  • Optech summary of vulnerability

BTCPay Server

• Add Lightning payout support

New Releases

• bdk v0.12.0 - miniscript, SOCK5 support, more
• bdk-cli v0.3.0 - rpc blockchain client, compactblockfilter, more
• bitcoin-s v1.8.0 - tor negotiation
• BlueWallet v6.2.8 - custom derivation, tor toggle, more
• c-lightning v0.10.2rc1
• eclair v0.6.2 - fixes CVE-2021-4159, anchor outputs, per node relays fees, more
• electrs v0.9.0 - fetch blocks over bitcoin gossip network
• hodlcontracts - non-custodial oracle and escrow system for the lightning network
• joinmarket v0.9.3 - urgent maker bugfix
• joininbox v0.6.3 - Bitcoin Core 22.0
• immortan v0.3.5 - RBF support
• lnd v0.13.3-beta - fixes CVE-2021-41593
• ln-probing-simulator
• nthkey-ios v1.0.4 - bech32m support
• mercury-wallet v0.4.31 - mainnet release of statechain wallet
• phoenix v1.4.17 - Lightning Address support
• raspiblitz v1.7.1 - c-lightning support
• rust-lightning - api updates, bug fixes
• secp256k1-py - python FFI bindings for libsecp256k1, discussion
• SimpleBitcoinWallet v2.2.14-16 - - CPFP, RBF-cancel, HODL payments, batch sends
• specter-desktop v1.7.0
• thunderhub v0.12.29 - Lightning Address support
• umbrel v0.4.3 - lnd 0.13.3

Events and Podcasts

• Lightning Tidbits 706070
• LNMarkets - BOLT 12 with Rusty Russell

Mining

• Bitfury to go public
• New US mining facility powered by nuclear
• US becomes world’s biggest Bitcoin miner

Miscellaneous

• A list of all places where (single or double) hashing is used in Bitcoin protocol, discussion
• Adventures in Adaptor Signatures
• And the man with the tie - Anthony Towns
• Bitcoin UI Kit Screens
• Bitrefill adds support for Lightning Address top ups
• Blockstream sponsors Minimint, federated e-cash server
• Brink and the Stacks Foundation supporting Bitcoin Core with BTC Yield
• Carl Dong’s thoughts on libbitcoinkernel
• Contango and backwardation, risks of the ProShares Bitcoin ETF
• BitMEX grant to @440UrPp
• Differences between BIP70 and LNURL, discussion
• Rolling for Initiative - Anthony Towns joins MIT DCI
• Rusty’s thoughts on updating Lightning gossip for taproot
• General full-RBF discussion
• Google antitrust filling thread
• How much does it cost to destroy Bitcoin?
• Introducing Flow: Effortlessly Create Lightning Channels
• Jonas Schnelli stepping down as Bitcoin Core maintainer
• Kraken commits to fund Bitcoin’s open-source Rust development ecosystem with Tamás Blummer Memorial Fund
• Lightning & Internet: choosing the right path
• Liquid and Taproot Activation
• Martin Zumsande announced as latest Brink fellow
• Okcoin renews grant to Marco Falke for another year
• Outsourced Stake
• Security Budget II, Low Fees, and Merged Mining
• Schnorr Wizardry
• Terminal Web supports Lightning Pool
• The State of Lightning
• Turing Machines on Bitcoin