From: Jonas Schnelli <dev@jonasschnelli•ch>
To: Pieter Wuille <pieter.wuille@gmail•com>,
Bitcoin Protocol Discussion
<bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] BIP 174 thoughts
Date: Tue, 19 Jun 2018 11:38:24 +0200 [thread overview]
Message-ID: <011F22E3-0116-4769-88FB-0CB675E5BCD5@jonasschnelli.ch> (raw)
In-Reply-To: <CAPg+sBhGMxXatsyCAqeboQKH8ASSFAfiXzxyXR9UrNFnah5PPw@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 2164 bytes --]
> * Key-value map model or set model.
> * Ability for Combiners to verify two PSBT are for the same transaction
> * Optional signing
> * Derivation from xpub or fingerprint
> * Generic key offset derivation
> * Hex encoding?
I think all of Pieters points are valid and reasonable thought, though I’m unsure if it would be worth changing the existing-implementation-breaking things like the k/v set model.
AFAIK things like non-hex-encoding or generic key offset derivation are extensions and would not break existing implementations.
Further thoughts on BIP174 from my side.
Key derivation in multisig:
From my understanding, the signers and the creator must have agreed – in advance to the PSBT use case – on a key derivation scheme.
BIP32 derivation is assumed, but may not always be the case.
Sharing xpubs (the chaincode) may be a concern in non-trust-relationships between signer(s) and the creator (regarding Pieters xpub/fingerprint concerns).
Providing the type 0x03, the bip32 derivation path is one form of a support to faster (or computational possible) derivation of the required keys for signing a particular input.
From my point of view, it is a support of additional metadata shared between creator and signer and provided from the creator to the signer for faster (or computation possible) key deviation.
I think it could be more flexible (generic) in BIP174.
It could be just a single child key {32-bit int}, or just a keypath ({32-bit int}]{32-bit int}…) which is very likely sufficient for a HWW to derive the relevant key without the creation of a lookup-window or other „maps".
It could even be an enciphered payload which was shared during address/redeem-script generation and „loops“ back during a signing request.
Maybe I’m overcomplicating things, but for practical multisig with HWWs, a simple BIP32-child-key-index or BIP32-keypath derivation support field should be sufficient.
A generic „derivation support field“, provided from the signer to the creator during address-generation that just „loops“ back during the PSBT use-cases is probably a overkill.
Thanks
—
/jonas
[-- Attachment #2: Message signed with OpenPGP --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
next prev parent reply other threads:[~2018-06-19 9:38 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-15 23:34 Pieter Wuille
2018-06-16 15:00 ` Peter D. Gray
2018-06-19 9:38 ` Jonas Schnelli [this message]
2018-06-19 14:20 ` matejcik
2018-06-19 15:20 ` Jonas Schnelli
2018-06-21 20:28 ` Peter D. Gray
2018-06-19 17:16 ` Pieter Wuille
2018-06-21 11:29 ` matejcik
2018-06-21 17:39 ` Pieter Wuille
2018-06-21 11:44 ` Tomas Susanka
2018-06-19 14:22 ` matejcik
2018-06-21 0:39 ` Achow101
2018-06-21 14:32 ` Tomas Susanka
2018-06-21 15:40 ` Greg Sanders
2018-06-21 19:56 ` Peter D. Gray
2018-06-21 21:39 ` Gregory Maxwell
2018-06-22 19:10 ` Pieter Wuille
2018-06-22 22:28 ` Achow101
2018-06-23 17:00 ` William Casarin
2018-06-23 20:33 ` Andrew Chow
2018-06-24 8:19 ` Andrea
2018-06-24 8:28 ` Andrew Chow
2018-06-24 9:00 ` Andrea
2018-06-23 18:27 ` Peter D. Gray
2018-06-25 19:47 ` Tomas Susanka
2018-06-25 20:10 ` Jonas Schnelli
2018-06-25 20:30 ` Achow101
2018-06-26 15:33 ` matejcik
2018-06-26 16:58 ` William Casarin
2018-06-26 17:11 ` Marek Palatinus
2018-06-27 14:11 ` matejcik
2018-06-26 20:30 ` Pieter Wuille
2018-06-27 14:04 ` matejcik
2018-06-27 15:06 ` Pieter Wuille
2018-06-29 9:53 ` matejcik
2018-06-29 19:12 ` Achow101
2018-06-29 20:31 ` Peter D. Gray
2018-07-04 13:19 ` matejcik
2018-07-04 18:35 ` Achow101
2018-07-05 17:23 ` Jason Les
2018-07-04 19:09 ` Pieter Wuille
2018-07-05 11:52 ` matejcik
2018-07-05 22:06 ` Pieter Wuille
2018-07-10 12:10 ` matejcik
2018-07-11 18:27 ` Pieter Wuille
2018-07-11 20:05 ` Gregory Maxwell
2018-07-11 20:54 ` [bitcoin-dev] BIP 174 thoughts on graphics vv01f
2018-06-26 21:56 ` [bitcoin-dev] BIP 174 thoughts Achow101
2018-06-27 6:09 ` William Casarin
2018-06-27 13:39 ` Andrea
2018-06-27 17:55 ` Achow101
2018-06-28 20:42 ` Rodolfo Novak
2018-07-05 19:20 ` William Casarin
2018-07-06 18:59 ` Achow101
2018-06-20 0:39 Jason Les
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=011F22E3-0116-4769-88FB-0CB675E5BCD5@jonasschnelli.ch \
--to=dev@jonasschnelli$(echo .)ch \
--cc=bitcoin-dev@lists$(echo .)linuxfoundation.org \
--cc=pieter.wuille@gmail$(echo .)com \
/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