From: ZmnSCPxj <ZmnSCPxj@protonmail•com>
To: Bastien TEINTURIER <bastien@acinq•fr>
Cc: Bitcoin Protocol Discussion
<bitcoin-dev@lists•linuxfoundation.org>,
"lightning-dev\\\\\\\\@lists.linuxfoundation.org"
<lightning-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] Batch exchange withdrawal to lightning requires covenants
Date: Tue, 17 Oct 2023 17:04:06 +0000 [thread overview]
Message-ID: <Ckp3N2cHGyyFyTp8IkjqYwnXsef1KxzhFs9vHQvFCpdWKUCrCfpxLBAgIXsKEtTNQqvfdyywt7weJd2pVz8UKn6egfRy46-xd17pnltcQyU=@protonmail.com> (raw)
In-Reply-To: <CACdvm3MuKmzQ1EFMJDc0ahhrG6xpD6Rr9Vh=ZTpVHa12ZALB0w@mail.gmail.com>
Good morning Bastien,
I have not gotten around to posting it yet, but I have a write-up in my computer with the title:
> Batched Splicing Considered Risky
The core of the risk is that if:
* I have no funds right now in a channel (e.g. the LSP allowed me to have 0 reserve, or this is a newly-singlefunded channel from the LSP to me).
* I have an old state (e.g. for a newly-singlefunded channel, it could have been `update_fee`d, so that the initial transaction is old state).
Then if I participate in a batched splice, I can disrupt the batched splice by broadcasting the old state and somehow convincing miners to confirm it before the batched splice.
Thus, it is important for *any* batched splicing mechanism to have a backout, where if the batched splice transaction can no longer be confirmed due to some participant disrupting it by posting an old commitment transaction, either a subset of the splice is re-created or the channels revert back to pre-splice state (with knowledge that the post-splice state can no longer be confirmed).
I know that current splicing tech is to run both the pre-splice and post-splice state simultaneously until the splicing transaction is confirmed.
However we need to *also* check if the splicing transaction *cannot* be confirmed --- by checking if the other inputs to the splice transaction were already consumed by transactions that have deeply confirmed, and in that case, to drop the post-splice state and revert to the pre-splice state.
I do not know if existing splice implementations actually perform such a check.
Unless all splice implementations do this, then any kind of batched splicing is risky.
Regards,
ZmnSCPxj
next prev parent reply other threads:[~2023-10-17 17:04 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-17 13:03 Bastien TEINTURIER
2023-10-17 17:04 ` ZmnSCPxj [this message]
2023-10-17 17:10 ` Greg Sanders
2023-10-17 17:17 ` ZmnSCPxj
2023-10-17 19:10 ` [bitcoin-dev] [Lightning-dev] " Antoine Riard
2023-10-18 14:35 ` Bastien TEINTURIER
2023-10-18 18:03 ` Antoine Riard
2023-10-19 7:35 ` Bastien TEINTURIER
2023-10-19 17:09 ` Antoine Riard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to='Ckp3N2cHGyyFyTp8IkjqYwnXsef1KxzhFs9vHQvFCpdWKUCrCfpxLBAgIXsKEtTNQqvfdyywt7weJd2pVz8UKn6egfRy46-xd17pnltcQyU=@protonmail.com' \
--to=zmnscpxj@protonmail$(echo .)com \
--cc=bastien@acinq$(echo .)fr \
--cc=bitcoin-dev@lists$(echo .)linuxfoundation.org \
--cc=lightning-dev@lists$(echo .)linuxfoundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox