path: root/9e/8f70850f9d2f6555031b384cac5d2ed88bdd55

Delivery-date: Thu, 27 Mar 2025 13:52:51 -0700
Received: from mail-qt1-f187.google.com ([209.85.160.187])
	by mail.fairlystable.org with esmtps  (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256
	(Exim 4.94.2)
	(envelope-from <bitcoindev+bncBD7O3WHWY4JRBGHVS27QMGQEVRNGROQ@googlegroups.com>)
	id 1txuDZ-0000FY-V1
	for bitcoindev@gnusha.org; Thu, 27 Mar 2025 13:52:51 -0700
Received: by mail-qt1-f187.google.com with SMTP id d75a77b69052e-4769a1db721sf31443551cf.3
        for <bitcoindev@gnusha.org>; Thu, 27 Mar 2025 13:52:49 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=googlegroups.com; s=20230601; t=1743108764; x=1743713564; darn=gnusha.org;
        h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post
         :list-id:mailing-list:precedence:x-original-sender:mime-version
         :subject:references:in-reply-to:message-id:to:from:date:sender:from
         :to:cc:subject:date:message-id:reply-to;
        bh=uczm8VxFpql0dvDXhllvLmcMKwevXkWZUPqUCRBIuxg=;
        b=u1EyGeil6g0lM3F32G2kyfM6nPCR6Qo/9yeLySvPZuGIAbx6g3mOMWCOAbQl6fcp9P
         8VhKZkN9YZrN1aewQP8NIXAWvH98Zh/+PGtCTr8ET0ZShfPgP5xi5HM9BFq/9bbX2vfy
         23OSjCNINsyU6cgP97KvhJlTV1t0+PwYXFAH3Mugij3fE10BMzvpv7SIwX283u62G6WX
         WUC0OTT1KBNpc2A5oF0v64ovDmN4JX98Cq+qGuIgB9mrP4JUTC1viqtzJqnbvy8dxNZD
         jhVhEqKkau8PMboipB5T/2Hr9yn4BvHipIkujIgyAHSPioP+VooHEu0wA3cmeUNIS1Ic
         hovg==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20230601; t=1743108764; x=1743713564; darn=gnusha.org;
        h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post
         :list-id:mailing-list:precedence:x-original-sender:mime-version
         :subject:references:in-reply-to:message-id:to:from:date:from:to:cc
         :subject:date:message-id:reply-to;
        bh=uczm8VxFpql0dvDXhllvLmcMKwevXkWZUPqUCRBIuxg=;
        b=NZMHMKngHVLJqz5QY0LMuv/xadEu5TFrxOk+VCdbrkASgCYKzgQ2XGMbCcjezvxtMa
         IWlPdPQtAaSX1IkjdCOQPS99ECmmcwPbh9K7FL5yMwPiIaSj37Z8Bpc0BSDhFosd8f3W
         6FQRjH8h1jIc3swbfgCWVpzMpwecDFp2HXZ4Ao+1knfoFM9Wf0b1exq37auVhB9t/+o0
         Glac+heC2qoRbkCsqttsDaHJE8/Y/C0xI7+TSjbkSLqjGkA0zsCkcxu1cjyuf61jbwQj
         IB/h1FfUV4hbVMEATL0zfggngtddSSR2ls913TctCZFb0vupatxQlJrUC5QF5pEobwsv
         OC4g==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=1e100.net; s=20230601; t=1743108764; x=1743713564;
        h=list-unsubscribe:list-subscribe:list-archive:list-help:list-post
         :list-id:mailing-list:precedence:x-original-sender:mime-version
         :subject:references:in-reply-to:message-id:to:from:date:x-beenthere
         :x-gm-message-state:sender:from:to:cc:subject:date:message-id
         :reply-to;
        bh=uczm8VxFpql0dvDXhllvLmcMKwevXkWZUPqUCRBIuxg=;
        b=esK+MDCvAdZrkibiN1s0eBVTkQzYf3x6IDlsgyuo/eMdtLy5W660FToCWgD6VhmT2W
         iLax03lsTuPXyGrxiayCjbLr/wKU9xuCbV4BK7JLBInB3dKbZfbwkDgNYYMfORbtYwVV
         epxX4kF6NNyusmi6lSyOmnoDGkcAedBjXpwEIDCE6hojrDZK8JJfQBiXuncR9etwv2ce
         0049qnZFTFweY1QPXUW5x7/5KIFOfxPGosJqRd08kPCse4gCbMnuMQ4Zl+Kpza9SXsVQ
         YNcbhJZX18rEjoUMErQ/xoiTOFEoU8KoT9UpSv95dL7o9/nx4g+0zexjT8MDrKZlp/S3
         K14Q==
Sender: bitcoindev@googlegroups.com
X-Forwarded-Encrypted: i=1; AJvYcCXFJOqm142jdaonQU4Cnif4YZ2wqJEs+hfPZfdpwh5M8gqlJKetfofjhwXGluewIFIRM82dNfwi6bkF@gnusha.org
X-Gm-Message-State: AOJu0YxQks+b3m/7C6K7kPGqjM58eT3WN7ZNr2rAdJVyL9HsUGqRiT5S
	pi0sVzjnRi6KekTmUINM0UV2c9ORGB2xzh2aDauBrzaMbAvdHCkh
X-Google-Smtp-Source: AGHT+IGeavunNSKiMVxlc2Ug1ExwRsVLiWrHlrvDgTfWJxuId6fWEH9Yn6H4KsOUkap3bOUDDPhLqw==
X-Received: by 2002:a05:622a:5c18:b0:476:a7f2:272d with SMTP id d75a77b69052e-4776e21d4e3mr80071061cf.44.1743108763545;
        Thu, 27 Mar 2025 13:52:43 -0700 (PDT)
X-BeenThere: bitcoindev@googlegroups.com; h=ARLLPAI2eyT//MmNn/QDEaCDW7oQW0YC/UHlnFxrEU+c+Rzghw==
Received: by 2002:a05:622a:1487:b0:476:70d8:43d2 with SMTP id
 d75a77b69052e-4776e4d06c8ls17235561cf.2.-pod-prod-00-us; Thu, 27 Mar 2025
 13:52:39 -0700 (PDT)
X-Received: by 2002:a05:620a:f0e:b0:7c5:93f8:f4b1 with SMTP id af79cd13be357-7c5f9db8810mr37857285a.4.1743108759808;
        Thu, 27 Mar 2025 13:52:39 -0700 (PDT)
Received: by 2002:a05:620a:1da8:b0:7c5:3b15:3956 with SMTP id af79cd13be357-7c5da16645bms85a;
        Thu, 27 Mar 2025 13:45:21 -0700 (PDT)
X-Received: by 2002:a05:690c:f96:b0:6fd:346f:97ba with SMTP id 00721157ae682-70224f8c4aamr68137637b3.11.1743108319591;
        Thu, 27 Mar 2025 13:45:19 -0700 (PDT)
Date: Thu, 27 Mar 2025 13:45:19 -0700 (PDT)
From: jeremy <jeremy.l.rubin@gmail.com>
To: Bitcoin Development Mailing List <bitcoindev@googlegroups.com>
Message-Id: <afedbc69-8042-4fe8-99c2-279173a440f3n@googlegroups.com>
In-Reply-To: <TD8gP8PKw3th-0DrZznBXrXFILRkwr66wVRoiPC2di_e-NivCRKVjooVZIh7JJSV_C9rJEkKTvudWSG8CJsq16jPhQBjM0eVmPe8rir50Y4=@protonmail.com>
References: <uDAujRxk4oWnEGYX9lBD3e0V7a4V4Pd-c4-2QVybSZNcfJj5a6IbO6fCM_xEQEpBvQeOT8eIi1r91iKFIveeLIxfNMzDys77HUcbl7Zne4g=@protonmail.com>
 <CAGL6+mFQqTS21cQZ_aU=hXtMaKkw5ygAk2PT9hQpdB4THz9X_A@mail.gmail.com>
 <TD8gP8PKw3th-0DrZznBXrXFILRkwr66wVRoiPC2di_e-NivCRKVjooVZIh7JJSV_C9rJEkKTvudWSG8CJsq16jPhQBjM0eVmPe8rir50Y4=@protonmail.com>
Subject: Re: [bitcoindev] Consensus Cleanup BIP draft
MIME-Version: 1.0
Content-Type: multipart/mixed; 
	boundary="----=_Part_55052_1515534136.1743108319260"
X-Original-Sender: Jeremy.L.Rubin@gmail.com
Precedence: list
Mailing-list: list bitcoindev@googlegroups.com; contact bitcoindev+owners@googlegroups.com
List-ID: <bitcoindev.googlegroups.com>
X-Google-Group-Id: 786775582512
List-Post: <https://groups.google.com/group/bitcoindev/post>, <mailto:bitcoindev@googlegroups.com>
List-Help: <https://groups.google.com/support/>, <mailto:bitcoindev+help@googlegroups.com>
List-Archive: <https://groups.google.com/group/bitcoindev
List-Subscribe: <https://groups.google.com/group/bitcoindev/subscribe>, <mailto:bitcoindev+subscribe@googlegroups.com>
List-Unsubscribe: <mailto:googlegroups-manage+786775582512+unsubscribe@googlegroups.com>,
 <https://groups.google.com/group/bitcoindev/subscribe>
X-Spam-Score: -0.5 (/)

------=_Part_55052_1515534136.1743108319260
Content-Type: multipart/alternative; 
	boundary="----=_Part_55053_1253683265.1743108319260"

------=_Part_55053_1253683265.1743108319260
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

> First of all, i do not expect to remove any of the mitigations from the=
=20
BIP at this stage. The fact that each of these mitigations was researched=
=20
and discussed at length by multiple people over the past year gives me=20
confidence to move forward with every single one of those. Otherwise i=20
would not have proposed this BIP in the first place.

I'd recommend taking a much more flexible mindset at this stage. The set of=
=20
eyeballs you get at a pre-BIP and BIP stage, and the level of attention are=
=20
very different, and this type of messaging is very discouraging for someone=
=20
with expertise to care to put review in v.s. disregarding the effort as=20
non-constructive.

Critically:

In your "discussed at length" proposal, you failed to realize that there=20
were indeed 64 byte transactions on-chain until it was pointed out to you 7=
=20
days ago.

You also include a hack using coinbase nSequence -- have you bothered to=20
talk to anyone in the mining business how they feel about that? Are you=20
sure no ASIC in the wild don't hardcode a field that never needed to be set=
=20
before?

I'm also personally strongly against removing 64-byte transactions. It's a=
=20
wart in how transactions work, and future upgrades (especially around tx=20
programmability) might integrate very poorly with this kind of edge=20
condition.

regards,

Jeremy

On Thursday, March 27, 2025 at 3:36:13=E2=80=AFPM UTC-4 Antoine Poinsot wro=
te:

> Hi Chris,
>
> As i already explained on this very list 2 months ago [0], i don't find=
=20
> the argument for splitting my BIP convincing. On the contrary i think it=
=20
> would be counterproductive as it would create more churn, invite=20
> bikeshedding and overall impede progress on this proposal.
>
> we've successfully activated multiple BIPs within a single soft fork in=
=20
> the past=E2=80=94e.g., BIP141 and BIP143 in Segwit, as well as BIP341, BI=
P342, and=20
> BIP343 in Taproot.
>
>
> Those BIPs had much more content to them. The specifications of the=20
> Consensus Cleanup is trivial in comparison: they fit in less than a dozen=
=20
> lines of text when described in details. Splitting them in 4 different BI=
Ps=20
> with a single or a couple lines of specifications would just introduce=20
> unnecessary overhead.
>
> if one of the proposed changes turns out to be controversial, we could=20
> remove it without holding up the rest of the improvements.
>
>
> First of all, i do not expect to remove any of the mitigations from the=
=20
> BIP at this stage. The fact that each of these mitigations was researched=
=20
> and discussed at length by multiple people over the past year gives me=20
> confidence to move forward with every single one of those. Otherwise i=20
> would not have proposed this BIP in the first place.
>
> Now, even if somehow we should drop one of the mitigations from the=20
> proposal, having them in separate BIPs does not make that any easier.
>
> More active contributors to the project may have stronger opinions on the=
=20
> best approach there.
>
>
> Yes.
>
> Best,
> Antoine
>
> [0]=20
> https://gnusha.org/pi/bitcoindev/mm_NvE4votqtjm455I3AmdrLOTzwgfFpqbtbFFNy=
0Zf2PywGt220MXfn76it60q_kbnS9Rw97cv6XzqogNgQMfIXi6-HdOnamw7tUrMtmXc=3D@prot=
onmail.com
> On Thursday, March 27th, 2025 at 6:46 AM, Chris Stewart <
> stewart....@gmail.com> wrote:
>
> Hi Antoine,=20
>
> First off, concept ACK. My concerns are procedural rather than objections=
=20
> to the individual security fixes themselves.
>
> The "Great Consensus Cleanup" is a fantastic brand for communicating thes=
e=20
> protocol changes to non-technical users. However, since this is a technic=
al=20
> forum and we are producing BIPs intended for technical audiences, I belie=
ve=20
> we should document these changes in separate BIPs.
>
> The proposed security fixes are largely unrelated from a technical=20
> standpoint:
>
>    1.=20
>   =20
>    Timewarp attack mitigation
>    2.=20
>   =20
>    Worst-case block validation constraints
>    3.=20
>   =20
>    Disallowing 64-byte transactions
>    4.=20
>   =20
>    Avoiding duplicate transactions
>   =20
> We should absolutely retain the "Great Consensus Cleanup" branding while=
=20
> independently documenting each security enhancement.
>
> A common concern I=E2=80=99ve heard about splitting this BIP is that depl=
oying=20
> soft forks is difficult, so all changes should be bundled together. While=
=20
> soft fork deployment is indeed challenging, we've successfully activated=
=20
> multiple BIPs within a single soft fork in the past=E2=80=94e.g., BIP141 =
and BIP143=20
> in Segwit, as well as BIP341, BIP342, and BIP343 in Taproot. If the=20
> community reaches consensus, we can still deploy all these changes=20
> together, even if they are documented separately.
>
> This approach also provides flexibility: if one of the proposed changes=
=20
> turns out to be controversial, we could remove it without holding up the=
=20
> rest of the improvements. Additionally, once these fixes are deployed,=20
> there will likely be significant research and documentation to incorporat=
e,=20
> and maintaining independent BIPs will make it easier to manage that growt=
h.
>
> I do see merit in implementing all the security fixes in a single PR for=
=20
> Bitcoin Core. More active contributors to the project may have stronger=
=20
> opinions on the best approach there.
>
> -Chris=20
> ------------------------------
>
>
>
>
> On Wed, Mar 26, 2025 at 1:23=E2=80=AFPM 'Antoine Poinsot' via Bitcoin Dev=
elopment=20
> Mailing List <bitco...@googlegroups.com> wrote:
>
>> Hi everyone,
>>
>> About two months ago i shared an update on this list about my (and=20
>> others', really) work on the
>> Consensus Cleanup [0]. I am now ready to share a BIP draft for a=20
>> Consensus Cleanup soft fork.
>>
>> The BIP draft can be found here:=20
>> https://github.com/darosior/bips/blob/consensus_cleanup/bip-cc.md
>>
>> It includes the following fixes:
>> - a restriction on the timestamp of the first and last blocks of a=20
>> difficulty adjustment period to
>> address the Timewarp and Murch-Zawy attacks;
>> - a limit on the number of legacy signature operations that may be=20
>> executed in validating a single
>> transaction to address long block validation times;
>> - making 64 bytes transactions invalid to address weaknesses in the bloc=
k=20
>> Merkle tree construction;
>> - mandating coinbase transactions be timelocked to their block height to=
=20
>> prevent future transaction
>> duplication without resorting to BIP30 validation.
>>
>> This BIP draws on the 2019 Great Consensus Cleanup proposal from Matt=20
>> Corallo [1]. A number of
>> people contributed ideas, testing, data or useful discussions. This=20
>> includes Ava Chow, Matt Corallo,
>> Mark Erhardt, Brian Groll, David A. Harding, Sjors Provoost, Anthony=20
>> Towns, Greg Sanders, Chris
>> Stewart, Eric Voskuil, @0xb10c and others.
>>
>> Antoine Poinsot
>>
>> [0]=20
>> https://gnusha.org/pi/bitcoindev/jiyMlvTX8BnG71f75SqChQZxyhZDQ65kldcugeI=
DJVJsvK4hadCO3GT46xFc7_cUlWdmOCG0B_WIz0HAO5ZugqYTuX5qxnNLRBn3MopuATI=3D@pro=
tonmail.com
>> [1]=20
>> https://github.com/TheBlueMatt/bips/blob/7f9670b643b7c943a0cc6d2197d3eab=
e661050c2/bip-XXXX.mediawiki
>>
>> --=20
>> You received this message because you are subscribed to the Google Group=
s=20
>> "Bitcoin Development Mailing List" group.
>> To unsubscribe from this group and stop receiving emails from it, send a=
n=20
>> email to bitcoindev+...@googlegroups.com.
>> To view this discussion visit=20
>> https://groups.google.com/d/msgid/bitcoindev/uDAujRxk4oWnEGYX9lBD3e0V7a4=
V4Pd-c4-2QVybSZNcfJj5a6IbO6fCM_xEQEpBvQeOT8eIi1r91iKFIveeLIxfNMzDys77HUcbl7=
Zne4g%3D%40protonmail.com
>> .
>>
>
>

--=20
You received this message because you are subscribed to the Google Groups "=
Bitcoin Development Mailing List" group.
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to bitcoindev+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/bitcoindev/=
afedbc69-8042-4fe8-99c2-279173a440f3n%40googlegroups.com.

------=_Part_55053_1253683265.1743108319260
Content-Type: text/html; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

&gt;=C2=A0<span style=3D"font-family: Arial, sans-serif;">First of all, i d=
o not expect to remove any of the mitigations from the BIP at this stage.=
=C2=A0The fact that each of these mitigations was researched and discussed =
at length by multiple people over the past year gives me confidence to move=
 forward with every single one of those. Otherwise i would not have propose=
d this BIP in the first place.</span><div style=3D"font-family: Arial, sans=
-serif;"><br /></div><div style=3D"font-family: Arial, sans-serif;">I'd rec=
ommend taking a much more flexible mindset at this stage. The set of eyebal=
ls you get at a pre-BIP and BIP stage, and the level of attention are very =
different, and this type of messaging is very discouraging for someone with=
 expertise to care to put review in v.s. disregarding the effort as non-con=
structive.</div><div style=3D"font-family: Arial, sans-serif;"><br /></div>=
<div style=3D"font-family: Arial, sans-serif;">Critically:</div><div style=
=3D"font-family: Arial, sans-serif;"><br /></div><div style=3D"font-family:=
 Arial, sans-serif;">In your "discussed at length" proposal, you failed to =
realize that there were indeed 64 byte transactions on-chain until it was p=
ointed out to you 7 days ago.</div><div style=3D"font-family: Arial, sans-s=
erif;"><br /></div><div style=3D"font-family: Arial, sans-serif;">You also =
include a hack using coinbase nSequence -- have you bothered to talk to any=
one in the mining business how they feel about that? Are you sure no ASIC i=
n the wild don't hardcode a field that never needed to be set before?</div>=
<div style=3D"font-family: Arial, sans-serif;"><br /></div><div style=3D"fo=
nt-family: Arial, sans-serif;">I'm also personally strongly against removin=
g 64-byte transactions. It's a wart in how transactions work, and future up=
grades (especially around tx programmability) might integrate very poorly w=
ith this kind of edge condition.</div><div style=3D"font-family: Arial, san=
s-serif;"><br /></div><div style=3D"font-family: Arial, sans-serif;">regard=
s,</div><div style=3D"font-family: Arial, sans-serif;"><br /></div><div sty=
le=3D"font-family: Arial, sans-serif;">Jeremy</div><div style=3D"font-famil=
y: Arial, sans-serif;"><br /></div><div class=3D"gmail_quote"><div dir=3D"a=
uto" class=3D"gmail_attr">On Thursday, March 27, 2025 at 3:36:13=E2=80=AFPM=
 UTC-4 Antoine Poinsot wrote:<br/></div><blockquote class=3D"gmail_quote" s=
tyle=3D"margin: 0 0 0 0.8ex; border-left: 1px solid rgb(204, 204, 204); pad=
ding-left: 1ex;"><div style=3D"font-family:Arial,sans-serif;font-size:14px"=
>Hi Chris,</div><div style=3D"font-family:Arial,sans-serif;font-size:14px">=
<br></div><div style=3D"font-family:Arial,sans-serif;font-size:14px">As i a=
lready explained on this very list 2 months ago [0], i don&#39;t find the a=
rgument for splitting my BIP convincing. On the contrary i think it would b=
e counterproductive as it would create more churn, invite bikeshedding and =
overall impede progress on this proposal.</div><div style=3D"font-family:Ar=
ial,sans-serif;font-size:14px"><br></div><blockquote style=3D"border-left:3=
px solid rgb(200,200,200);border-color:rgb(200,200,200);padding-left:10px;c=
olor:rgb(102,102,102)"><div style=3D"font-family:Arial,sans-serif;font-size=
:14px">we&#39;ve successfully activated multiple BIPs within a single soft =
fork in=20
the past=E2=80=94e.g., BIP141 and BIP143 in Segwit, as well as BIP341, BIP3=
42,=20
and BIP343 in Taproot.<br></div></blockquote><div style=3D"font-family:Aria=
l,sans-serif;font-size:14px"><br></div><div style=3D"font-family:Arial,sans=
-serif;font-size:14px">Those BIPs had much more content to them. The specif=
ications of the Consensus Cleanup is trivial in comparison: they fit in les=
s than a dozen lines of text when described in details. Splitting them in 4=
 different BIPs with a single or a couple lines of specifications would jus=
t introduce unnecessary overhead.</div><div style=3D"font-family:Arial,sans=
-serif;font-size:14px"><br></div><blockquote style=3D"border-left:3px solid=
 rgb(200,200,200);border-color:rgb(200,200,200);padding-left:10px;color:rgb=
(102,102,102)"><div style=3D"font-family:Arial,sans-serif;font-size:14px">i=
f one of the proposed changes turns out to be controversial, we could=20
remove it without holding up the rest of the improvements.<br></div></block=
quote><div style=3D"font-family:Arial,sans-serif;font-size:14px"><br>First =
of all, i do not expect to remove any of the mitigations from the BIP at th=
is stage.=C2=A0The fact that each of these mitigations was researched and d=
iscussed at length by multiple people over the past year gives me confidenc=
e to move forward with every single one of those. Otherwise i would not hav=
e proposed this BIP in the first place.</div><div style=3D"font-family:Aria=
l,sans-serif;font-size:14px"><br></div><div style=3D"font-family:Arial,sans=
-serif;font-size:14px">Now, even if somehow we should drop one of the mitig=
ations from the proposal, having them in separate BIPs does not make that a=
ny easier.</div><div style=3D"font-family:Arial,sans-serif;font-size:14px">=
<br></div><blockquote style=3D"border-left:3px solid rgb(200,200,200);borde=
r-color:rgb(200,200,200);padding-left:10px;color:rgb(102,102,102)"><div sty=
le=3D"font-family:Arial,sans-serif;font-size:14px">More active contributors=
 to the project may have stronger opinions on the best approach there.<br><=
/div></blockquote><div style=3D"font-family:Arial,sans-serif;font-size:14px=
"><br></div><div style=3D"font-family:Arial,sans-serif;font-size:14px">Yes.=
</div><div style=3D"font-family:Arial,sans-serif;font-size:14px"><br></div>=
<div style=3D"font-family:Arial,sans-serif;font-size:14px">Best,<br>Antoine=
<br></div><div style=3D"font-family:Arial,sans-serif;font-size:14px"><br></=
div><div style=3D"font-family:Arial,sans-serif;font-size:14px">[0] <span><a=
 rel=3D"noreferrer nofollow noopener" href=3D"https://gnusha.org/pi/bitcoin=
dev/mm_NvE4votqtjm455I3AmdrLOTzwgfFpqbtbFFNy0Zf2PywGt220MXfn76it60q_kbnS9Rw=
97cv6XzqogNgQMfIXi6-HdOnamw7tUrMtmXc=3D@protonmail.com" target=3D"_blank" d=
ata-saferedirecturl=3D"https://www.google.com/url?hl=3Den&amp;q=3Dhttps://g=
nusha.org/pi/bitcoindev/mm_NvE4votqtjm455I3AmdrLOTzwgfFpqbtbFFNy0Zf2PywGt22=
0MXfn76it60q_kbnS9Rw97cv6XzqogNgQMfIXi6-HdOnamw7tUrMtmXc%3D@protonmail.com&=
amp;source=3Dgmail&amp;ust=3D1743192218069000&amp;usg=3DAOvVaw1ytCP1TJj9p7w=
S1cIgK6-j">https://gnusha.org/pi/bitcoindev/mm_NvE4votqtjm455I3AmdrLOTzwgfF=
pqbtbFFNy0Zf2PywGt220MXfn76it60q_kbnS9Rw97cv6XzqogNgQMfIXi6-HdOnamw7tUrMtmX=
c=3D@protonmail.com</a></span><br></div><div>
        On Thursday, March 27th, 2025 at 6:46 AM, Chris Stewart &lt;<a href=
 data-email-masked rel=3D"nofollow">stewart....@gmail.com</a>&gt; wrote:<br=
>
        <blockquote type=3D"cite">
            <div><div dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><div di=
r=3D"ltr">Hi Antoine,
<p>First off, concept ACK. My concerns are procedural rather than objection=
s to the individual security fixes themselves.</p>
<p>The &quot;Great Consensus Cleanup&quot; is a fantastic brand for communi=
cating these protocol changes to non-technical users. However, since this i=
s a technical forum and we are producing BIPs intended for technical audien=
ces, I believe we should document these changes in separate BIPs.</p>
<p>The proposed security fixes are largely unrelated from a technical stand=
point:</p>
<ol><li>
<p>Timewarp attack mitigation</p>
</li><li>
<p>Worst-case block validation constraints</p>
</li><li>
<p>Disallowing 64-byte transactions</p>
</li><li>
<p>Avoiding duplicate transactions</p>
</li></ol>
<p>We should absolutely retain the &quot;Great Consensus Cleanup&quot; bran=
ding while independently documenting each security enhancement.</p>
<p>A common concern I=E2=80=99ve heard about splitting this BIP is that dep=
loying soft forks is difficult, so all changes should be bundled together. =
While soft fork deployment is indeed challenging, we&#39;ve successfully ac=
tivated multiple BIPs within a single soft fork in the past=E2=80=94e.g., B=
IP141 and BIP143 in Segwit, as well as BIP341, BIP342, and BIP343 in Taproo=
t. If the community reaches consensus, we can still deploy all these change=
s together, even if they are documented separately.</p>
<p>This approach also provides flexibility: if one of the proposed changes =
turns out to be controversial, we could remove it without holding up the re=
st of the improvements. Additionally, once these fixes are deployed, there =
will likely be significant research and documentation to incorporate, and m=
aintaining independent BIPs will make it easier to manage that growth.</p>
<p>I do see merit in implementing all the security fixes in a single PR for=
 Bitcoin Core. More active contributors to the project may have stronger op=
inions on the best approach there.<br><br></p><p>-Chris <br></p><hr><div><b=
r></div><div><br></div><div><br></div></div></div></div></div></div><div><d=
iv dir=3D"ltr"><div dir=3D"ltr"><div dir=3D"ltr"><br><div class=3D"gmail_qu=
ote"><div class=3D"gmail_attr" dir=3D"ltr">On Wed, Mar 26, 2025 at 1:23=E2=
=80=AFPM &#39;Antoine Poinsot&#39; via Bitcoin Development Mailing List &lt=
;<a href rel=3D"noreferrer nofollow noopener" data-email-masked>bitco...@go=
oglegroups.com</a>&gt; wrote:<br></div><blockquote style=3D"margin:0px 0px =
0px 0.8ex;border-left-width:1px;border-left-style:solid;padding-left:1ex;bo=
rder-left-color:rgb(204,204,204)" class=3D"gmail_quote">Hi everyone,<br>
<br>
About two months ago i shared an update on this list about my (and others&#=
39;, really) work on the<br>
Consensus Cleanup [0]. I am now ready to share a BIP draft for a Consensus =
Cleanup soft fork.<br>
<br>
The BIP draft can be found here: <a rel=3D"noreferrer nofollow noopener" hr=
ef=3D"https://github.com/darosior/bips/blob/consensus_cleanup/bip-cc.md" ta=
rget=3D"_blank" data-saferedirecturl=3D"https://www.google.com/url?hl=3Den&=
amp;q=3Dhttps://github.com/darosior/bips/blob/consensus_cleanup/bip-cc.md&a=
mp;source=3Dgmail&amp;ust=3D1743192218069000&amp;usg=3DAOvVaw3ccgxX-nKrN0D8=
EvdfMiWl">https://github.com/darosior/bips/blob/consensus_cleanup/bip-cc.md=
</a><br>
<br>
It includes the following fixes:<br>
- a restriction on the timestamp of the first and last blocks of a difficul=
ty adjustment period to<br>
  address the Timewarp and Murch-Zawy attacks;<br>
- a limit on the number of legacy signature operations that may be executed=
 in validating a single<br>
  transaction to address long block validation times;<br>
- making 64 bytes transactions invalid to address weaknesses in the block M=
erkle tree construction;<br>
- mandating coinbase transactions be timelocked to their block height to pr=
event future transaction<br>
  duplication without resorting to BIP30 validation.<br>
<br>
This BIP draws on the 2019 Great Consensus Cleanup proposal from Matt Coral=
lo [1]. A number of<br>
people contributed ideas, testing, data or useful discussions. This include=
s Ava Chow, Matt Corallo,<br>
Mark Erhardt, Brian Groll, David A. Harding, Sjors Provoost, Anthony Towns,=
 Greg Sanders, Chris<br>
Stewart, Eric Voskuil, @0xb10c and others.<br>
<br>
Antoine Poinsot<br>
<br>
[0] <a rel=3D"noreferrer nofollow noopener" href=3D"https://gnusha.org/pi/b=
itcoindev/jiyMlvTX8BnG71f75SqChQZxyhZDQ65kldcugeIDJVJsvK4hadCO3GT46xFc7_cUl=
WdmOCG0B_WIz0HAO5ZugqYTuX5qxnNLRBn3MopuATI=3D@protonmail.com" target=3D"_bl=
ank" data-saferedirecturl=3D"https://www.google.com/url?hl=3Den&amp;q=3Dhtt=
ps://gnusha.org/pi/bitcoindev/jiyMlvTX8BnG71f75SqChQZxyhZDQ65kldcugeIDJVJsv=
K4hadCO3GT46xFc7_cUlWdmOCG0B_WIz0HAO5ZugqYTuX5qxnNLRBn3MopuATI%3D@protonmai=
l.com&amp;source=3Dgmail&amp;ust=3D1743192218069000&amp;usg=3DAOvVaw1wB0lF9=
-vOTU1VvKTYb8Hi">https://gnusha.org/pi/bitcoindev/jiyMlvTX8BnG71f75SqChQZxy=
hZDQ65kldcugeIDJVJsvK4hadCO3GT46xFc7_cUlWdmOCG0B_WIz0HAO5ZugqYTuX5qxnNLRBn3=
MopuATI=3D@protonmail.com</a><br>
[1] <a rel=3D"noreferrer nofollow noopener" href=3D"https://github.com/TheB=
lueMatt/bips/blob/7f9670b643b7c943a0cc6d2197d3eabe661050c2/bip-XXXX.mediawi=
ki" target=3D"_blank" data-saferedirecturl=3D"https://www.google.com/url?hl=
=3Den&amp;q=3Dhttps://github.com/TheBlueMatt/bips/blob/7f9670b643b7c943a0cc=
6d2197d3eabe661050c2/bip-XXXX.mediawiki&amp;source=3Dgmail&amp;ust=3D174319=
2218069000&amp;usg=3DAOvVaw1CoU-1U8kZ0Be19fO02Bvj">https://github.com/TheBl=
ueMatt/bips/blob/7f9670b643b7c943a0cc6d2197d3eabe661050c2/bip-XXXX.mediawik=
i</a><br>
<br>
-- <br>
You received this message because you are subscribed to the Google Groups &=
quot;Bitcoin Development Mailing List&quot; group.<br>
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to <a href rel=3D"noreferrer nofollow noopener" data-email-masked>bitc=
oindev+...@googlegroups.com</a>.<br>
To view this discussion visit <a rel=3D"noreferrer nofollow noopener" href=
=3D"https://groups.google.com/d/msgid/bitcoindev/uDAujRxk4oWnEGYX9lBD3e0V7a=
4V4Pd-c4-2QVybSZNcfJj5a6IbO6fCM_xEQEpBvQeOT8eIi1r91iKFIveeLIxfNMzDys77HUcbl=
7Zne4g%3D%40protonmail.com" target=3D"_blank" data-saferedirecturl=3D"https=
://www.google.com/url?hl=3Den&amp;q=3Dhttps://groups.google.com/d/msgid/bit=
coindev/uDAujRxk4oWnEGYX9lBD3e0V7a4V4Pd-c4-2QVybSZNcfJj5a6IbO6fCM_xEQEpBvQe=
OT8eIi1r91iKFIveeLIxfNMzDys77HUcbl7Zne4g%253D%2540protonmail.com&amp;source=
=3Dgmail&amp;ust=3D1743192218069000&amp;usg=3DAOvVaw2LfFKyuEOjwC7OLflsqYwH"=
>https://groups.google.com/d/msgid/bitcoindev/uDAujRxk4oWnEGYX9lBD3e0V7a4V4=
Pd-c4-2QVybSZNcfJj5a6IbO6fCM_xEQEpBvQeOT8eIi1r91iKFIveeLIxfNMzDys77HUcbl7Zn=
e4g%3D%40protonmail.com</a>.<br>
</blockquote></div></div>
</div>
</div>
</div>

        </blockquote><br>
    </div></blockquote></div>

<p></p>

-- <br />
You received this message because you are subscribed to the Google Groups &=
quot;Bitcoin Development Mailing List&quot; group.<br />
To unsubscribe from this group and stop receiving emails from it, send an e=
mail to <a href=3D"mailto:bitcoindev+unsubscribe@googlegroups.com">bitcoind=
ev+unsubscribe@googlegroups.com</a>.<br />
To view this discussion visit <a href=3D"https://groups.google.com/d/msgid/=
bitcoindev/afedbc69-8042-4fe8-99c2-279173a440f3n%40googlegroups.com?utm_med=
ium=3Demail&utm_source=3Dfooter">https://groups.google.com/d/msgid/bitcoind=
ev/afedbc69-8042-4fe8-99c2-279173a440f3n%40googlegroups.com</a>.<br />

------=_Part_55053_1253683265.1743108319260--

------=_Part_55052_1515534136.1743108319260--