📅 Original date posted:2023-05-22
🗒️ Summary of this message: A new method for reducing steps in coinjoin using ALL|ANYONECANPAY sighash flag in PSBTs has been discovered and tested, with a proof of concept provided.
📝 Original message:Hi Bitcoin Developers,
I recently experimented with different sighash flags, PSBTs and realized ALL|ANYONECANPAY could be used to reduce some steps in coinjoin.
Steps:
- Register outputs.
- One user creates a signed PSBT with 1 input, all registered outputs and ALL|ANYONECANPAY sighash flag. Other participants keep adding their inputs to PSBT.
- Finalize and broadcast the transaction.
Proof of Concept (Aice and Bob): https://gitlab.com/-/snippets/2542297
Tx: https://mempool.space/testnet/tx/c6dd626591dca7e25bbd516f01b23171eb0f2b623471fcf8e073c87c1179c492
I plan to use this in joinstr if there are no major drawbacks and it can even be implemented by other coinjoin implementations.
/dev/fd0
floppy disk guy
Sent with Proton Mail secure email.
alicexbt [ARCHIVE] /
npub1w3…jzhn2
2023-06-07 23:21:57
in reply to nevent1q…rxnd
Author Public Key
npub1w30zwgl8947760cd62fawy9hqmxnq24cga5c8s5j6j7m07w96dnqzjzhn2Seen on
wss://relay.noswhere.comPublished at
2023-06-07 23:21:57Event JSON
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"content": "📅 Original date posted:2023-05-22\n🗒️ Summary of this message: A new method for reducing steps in coinjoin using ALL|ANYONECANPAY sighash flag in PSBTs has been discovered and tested, with a proof of concept provided.\n📝 Original message:Hi Bitcoin Developers,\n\nI recently experimented with different sighash flags, PSBTs and realized ALL|ANYONECANPAY could be used to reduce some steps in coinjoin.\n\nSteps:\n\n- Register outputs.\n- One user creates a signed PSBT with 1 input, all registered outputs and ALL|ANYONECANPAY sighash flag. Other participants keep adding their inputs to PSBT.\n- Finalize and broadcast the transaction.\n\nProof of Concept (Aice and Bob): https://gitlab.com/-/snippets/2542297\n\nTx: https://mempool.space/testnet/tx/c6dd626591dca7e25bbd516f01b23171eb0f2b623471fcf8e073c87c1179c492\n\nI plan to use this in joinstr if there are no major drawbacks and it can even be implemented by other coinjoin implementations. \n\n/dev/fd0\nfloppy disk guy\n\nSent with Proton Mail secure email.",
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