public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: "Russell O'Connor" <roconnor@blockstream.io>
To: Anthony Towns <aj@erisian.com.au>
Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Taproot proposal
Date: Fri, 28 Jun 2019 07:16:46 -0400	[thread overview]
Message-ID: <CAMZUoK==mXiJQjcJO+KgxtCSf9qBan4tgsGzfPKLjP4CHcZ_iA@mail.gmail.com> (raw)
In-Reply-To: <20190628094937.u5zisdhdyfc6g5ts@erisian.com.au>

[-- Attachment #1: Type: text/plain, Size: 1149 bytes --]

Hmm? If I'm following what you mean, that's not the P2P rules, it's the
> Unserialize code, in particular:
>
>   compat/assumptions.h:52:static_assert(sizeof(int) == 4, "32-bit int
> assumed");
>
>   serialize.h:289:uint64_t ReadCompactSize(Stream& is)
>
>   serialize.h-679-template<typename Stream, unsigned int N, typename T,
> typename V>
>   serialize.h-680-void Unserialize_impl(Stream& is, prevector<N, T>& v,
> const V&)
>   serialize.h-681-{
>   serialize.h-682-    v.clear();
>   serialize.h:683:    unsigned int nSize = ReadCompactSize(is);
>
>   (and other Unserialize_impl implementations)
>
> However, ReadCompactSize throws "size too large" if the return value is
> greater than MAX_SIZE == 0x02000000 =~ 33.5M, which prior to the implicit
> cast to 32 bits in Unserialize_impl. And it looks like that check's been
> there since Satoshi...
>
> So as far as I can see, that encoding's just unsupported/invalid, rather
> than equivalent/non-canonical?
>

Thanks for this correction!  I totally missed that MAX_SIZE == 0x02000000.
I think I mistook it for SIZE_MAX when reviewing this, or just didn't
notice it at all.

Cheers,
> aj
>
>

[-- Attachment #2: Type: text/html, Size: 1732 bytes --]

  reply	other threads:[~2019-06-28 11:16 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-05-06 17:57 [bitcoin-dev] Taproot proposal Pieter Wuille
2019-05-06 20:17 ` Luke Dashjr
2019-05-07 20:42   ` Sjors Provoost
2019-05-08  4:37     ` ZmnSCPxj
2019-05-08  5:16       ` ZmnSCPxj
2019-05-08 23:06     ` Pieter Wuille
2019-05-18 17:51       ` ZmnSCPxj
2019-05-08  3:44   ` ZmnSCPxj
2019-05-09 16:56     ` Johnson Lau
2019-05-10  5:38       ` ZmnSCPxj
2019-05-08  4:49   ` Anthony Towns
2019-05-08 13:10   ` Luke Dashjr
2019-05-21 17:20 ` Russell O'Connor
2019-05-23  2:06   ` Pieter Wuille
2019-05-23  2:32     ` Russell O'Connor
2019-05-22 14:14 ` John Newbery
2019-09-16 16:18   ` Greg Sanders
2019-09-17  4:09     ` ZmnSCPxj
2019-09-18 21:21       ` Pieter Wuille
2019-06-27  0:08 ` Russell O'Connor
2019-06-28  9:49   ` Anthony Towns
2019-06-28 11:16     ` Russell O'Connor [this message]
2019-08-09 14:58 Elichai Turkel
2019-08-09 18:29 ` Pieter Wuille

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='CAMZUoK==mXiJQjcJO+KgxtCSf9qBan4tgsGzfPKLjP4CHcZ_iA@mail.gmail.com' \
    --to=roconnor@blockstream.io \
    --cc=aj@erisian.com.au \
    --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