public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: SeedHammer Team <team@seedhammer.com>
To: "bitcoin-dev@lists.linuxfoundation.org"
	<bitcoin-dev@lists.linuxfoundation.org>
Subject: [bitcoin-dev] A proposal for a "PSBT for descriptors" format
Date: Thu, 23 Nov 2023 22:25:43 +0000	[thread overview]
Message-ID: <_pNFQS1xsa8HZF-9x3hk8EBZRfYAbzCAha1rKaFbwpfqMqjK51rGQspALrdYvB0R0r90iReLLsktJOfFowJG-wkX3E1NvPwtEQyMT95uo_4=@seedhammer.com> (raw)

Hi,

At SeedHammer we're interested in standard, compact output descriptors to make
self-contained metal engraved backups feasible. To that end, we're proposing a
descriptor format based on the PSBT binary encoding. The format has not reached
widespread consensus, never mind adoption, so at this point we're soliciting
comments before formally proposing it as a BIP.

See [proposal], [implementation] and [playground] for details and examples.

The format is a binary and compact serialization specification for the
[wallet-policies] BIP. Features:

- Based on the binary [BIP174] PSBT format, including re-using the compact
  PSBT_GLOBAL_XPUB encoding for extended keys.
- The descriptor itself is encoded in the same textual format as described
  in BIPs 380-386 (+389).
- Key references (always) use the wallet-policies format @<key-index>.
- Miniscript is trivially supported, except inline keys are not allowed, and
  pk(NAME) expressions are replaced with indexed (@<idx>) key references.
- Metadata such as labels and birthdate blocks are encoded as PSBT
  map entries.

Known issues:

- CBOR vs PSBT. Blockchain Commons believes[0] that a CBOR based format is better
  because it is a widely used binary encoding standard, whereas we believe the
  complexity of CBOR doesn't justify its cost compared to the PSBT encoding
  already widely supported by wallet software.
- The proposal specifies a separate header and magic; should the format instead be
  an extension to the PSBT format?

Thanks,
E

[proposal] https://github.com/BlockchainCommons/Research/issues/135
[implementation] https://github.com/seedhammer/bip-serialized-descriptors
[playground] https://go.dev/play/p/nouZlbbcEWt
[wallet-policies] https://github.com/bitcoin/bips/blob/bb98f8017a883262e03127ab718514abf4a5e5f9/bip-wallet-policies.mediawiki
[BIP174] https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki

[0] https://github.com/BlockchainCommons/Research/issues/135#issuecomment-1789644032


             reply	other threads:[~2023-11-23 22:26 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-23 22:25 SeedHammer Team [this message]
2023-11-30 23:12 ` [bitcoin-dev] A proposal for a "PSBT for descriptors" format Brandon Black

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='_pNFQS1xsa8HZF-9x3hk8EBZRfYAbzCAha1rKaFbwpfqMqjK51rGQspALrdYvB0R0r90iReLLsktJOfFowJG-wkX3E1NvPwtEQyMT95uo_4=@seedhammer.com' \
    --to=team@seedhammer.com \
    --cc=bitcoin-dev@lists.linuxfoundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
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