From: ZmnSCPxj <ZmnSCPxj@protonmail•com>
To: Christopher Gilliard <christopher.gilliard@gmail•com>,
Bitcoin Protocol Discussion
<bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] BIP - limiting OP_RETURN / HF
Date: Fri, 16 Apr 2021 23:52:48 +0000 [thread overview]
Message-ID: <iU2J5dWMIgqAf312ZCNmx38_hcYsKrcuqx84kniWeEdb0wP8jPZPvwHK3P-q1yvmQ5OtdMCwMFqPgwmsL7BUfE8PGUlrxW4rOM3slwHun3E=@protonmail.com> (raw)
In-Reply-To: <CAK=nyAz5+yMUA=XDcunA1eeachSisaJoYE2_yzTLj=B0r4=w5A@mail.gmail.com>
Good morning Christopher,
> >> But more importantly, adding limitations on OP_RETURN transactions is not helpful. Users who want to embed arbitrary data in their transactions can always do so by encoding their data inside the values of legacy multi-signature scriptpubkeys (pubkeys can be generated without knowing the private key in order to encode non-key related data). Not only can users do this, users have done this in the past. However, this behaviour is problematic because such multi-signature "data" scriptpubkeys are indistinguishable from "real" multisignature scriptpubkeys, and thus must be kept in the UTXO set. This differs from outputs using OP_RETURN which are provably unspendable, and therefore can be safely omitted from the UTXO set.
>
> This sounds like a good justification to remove the legacy multi-signature capabilities as well.
The same technique can be used on P2PKH as well --- the "pubkey hash" need not be a hash of a public key, it can be a 20-byte commitment, or even an ASCII message like "ZmnSCPxj is the best" (20 characters, I counted).
There is nothing that *can* check if the hash of a public key is indeed the hash of a public key unless you actually reveal the public key.
If you need a 32-byte commitment, a P2WSH would work --- again the "script hash" need not be a hash of a script, it can be any 32-byte commitment.
In all these cases you have to waste 547 satoshi, but that tends to be small compared to tx fees currently.
Regards,
ZmnSCPxj
next prev parent reply other threads:[~2021-04-16 23:53 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-16 7:45 Christopher Gilliard
2021-04-16 13:56 ` Russell O'Connor
2021-04-16 15:34 ` Christopher Gilliard
2021-04-16 15:55 ` Andrew Poelstra
2021-04-16 23:52 ` ZmnSCPxj [this message]
2021-04-17 3:57 ` Christopher Gilliard
2021-04-17 15:50 ` Peter Todd
2021-04-17 16:57 ` Christopher Gilliard
2021-04-16 13:59 ` Clark Moody
2021-04-16 15:33 ` Christopher Gilliard
2021-04-16 16:32 ` Jeremy
2021-04-16 17:05 ` Christopher Gilliard
2021-04-16 18:00 ` Jeremy
2021-04-16 19:15 ` Kostas Karasavvas
2021-04-16 20:12 ` Christopher Gilliard
2021-04-17 7:41 ` Kostas Karasavvas
2021-04-16 20:30 ` Ruben Somsen
2021-04-16 21:09 ` Christopher Gilliard
2021-04-20 1:23 ` yanmaani
2021-04-20 8:45 ` Zach Greenwood
2021-04-20 17:12 ` Christopher Gilliard
2021-04-20 19:07 ` Ruben Somsen
2021-05-03 5:17 ` ZmnSCPxj
2021-05-04 12:51 ` Ruben Somsen
2021-04-20 1:22 ` yanmaani
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='iU2J5dWMIgqAf312ZCNmx38_hcYsKrcuqx84kniWeEdb0wP8jPZPvwHK3P-q1yvmQ5OtdMCwMFqPgwmsL7BUfE8PGUlrxW4rOM3slwHun3E=@protonmail.com' \
--to=zmnscpxj@protonmail$(echo .)com \
--cc=bitcoin-dev@lists$(echo .)linuxfoundation.org \
--cc=christopher.gilliard@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