To: bitcoin-dev@lists.linuxfoundation.org
From: Andreas Schildbach <andreas@schildbach.de>
Date: Mon, 21 Oct 2019 10:44:16 +0200
Message-ID: <qojr51$7pnq$1@blaine.gmane.org>
References: <CAK51vgDO2Tg38XbW0pqAnO3ETJ_qf8owRsUYsTXmrf7H2yGZtw@mail.gmail.com>
	<CAFmfg2u3cLwG4h=tSF1+ho__1n2n4xyBGH+mwQgVYE9c_s+EMw@mail.gmail.com>
	<CAFmfg2sU=ur7NdzU6r9bGC=xZqcX7WA7ux-r8QOwNa+FKhS4Pw@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
Openpgp: preference=signencrypt
Autocrypt: addr=andreas@schildbach.de; keydata=
	xsDiBD/S9DARBACgg0IF3cCFaNXbQtCAZBpiZRawQAfsfL87sHhy1xq3UwR4RmQKsWjtZQ9C
	7kSDTkzzn7Sqg+YtXgiJdGeYinSMy+6mBKQjtrIKLikbjB1ORTfA29m7m7VTBY9X3Cvmpm0+
	0mWvrQ9hSpq8adXitY4Z+/VB/1YSo77RakfNr3sQOwCgzrXH37AlAu307IgOOFnI1y78Y4cD
	/29gtaY3/u8ThFI/mXBOHnfXaIVGLYKtlf2Lyj2JnixhhzxEpuDJ0lkcyNQ0N7Ky8ohJS3tG
	ShwHjsQNtqK2V1DomsUnDI/W4hJNCSd0zfIoQgHvE1RbOyOpz4F+CNw8uQcxwE5FmwRtk6xa
	zJsiMVKLFhKr6LnMoVaNi8mZZFKzA/9HcXAse5epfrZD1tt7dHr58+egIA0OkoQ8oUgqCgN1
	4qmUxQoWTdmvet0E+XaHcowr1fXu79uQ2zuvHSk/S4mjP6uT+XOxENVcKRUtyEBtSzFDyyCj
	853KrBQSppCgxS8loHj1g1YIKqu97kGVtfmHM9L9TPVA1opuYOcJh7iJ9s0qQW5kcmVhcyBT
	Y2hpbGRiYWNoIDxhbmRyZWFzQHNjaGlsZGJhY2guZGU+wl4EExECAB4FAj/S9DACGwMGCwkI
	BwMCAxUCAwMWAgECHgECF4AACgkQymYr4YuHemD4NACePnpSANmR2vrZVv+BteOva6gzOJ0A
	nioa6JoKCYx3jQOIqoBGcBUkc8q1zsFNBD/S9DgQCACctel4AnL7nuh+Uv+IBz0GMvu6Ewdn
	sVCOLf54neIxuaW4BC5RYAdS6Tkp3hxv+ZfA0Uv6X3nz4tOsVHD50+CCq51pRlnbUwcWcn9e
	nynJyddTjei+JmJrdOJOAzWa/al8YagjQSZqgD6mmPUy/a201Bh0L2zbLmxQMFg+PPB81j4y
	UmSXmhYzg/+SonZ3lr9pJNtoZszg95NDyYBceiF5RSw4Qusi+C5/W3nIKzuaIKZijE9Dvo6D
	W6ggbB/gSxDTSjvrnvvXeG1SdlKLeFvsJ9y/0ro3EP01RRVJvA5RaM5W2MRbwGuSRcSw8B74
	6ijEOqSh0IYLXoHdV7Vj4Qt/AAMFB/9ZcgxVGvs2ob6MCTVdPLlVKRKDn7RjZiDE6hRa/jp7
	ewdstjjc22DU/jCz16IX75B/sr1cDJqbChONFdljjQNWe2cTFXSazUjsyZa35+KvehDi7cAU
	+vCYmisMpkPM41hR6HYqjadDp6gOVJTnHPcJ6EPdgUQTsNQH3dCTD68b5WwzBEBNLdwyDGLK
	McExzaOClwwSeHBmnj72O7Chdhn/M/2+fpTUPqhp/0sflVyR/ILyc/KEp85pwani2dXuZ02i
	gSaSIBwQJOVrjsUTwp2Wxdmywt13/cGGVlsGLe8lY0Kv6G43/eip+42OfIVhxRgARRtJ5KjK
	chTLwfl3tbgawkkEGBECAAkFAj/S9DgCGwwACgkQymYr4YuHemAWjACgtRlmiISVlCf7/mum
	klJfLM6wKIMAnA2uS1BS4d7GJkQp09ViaWmUUsMc
In-Reply-To: <CAFmfg2sU=ur7NdzU6r9bGC=xZqcX7WA7ux-r8QOwNa+FKhS4Pw@mail.gmail.com>
Content-Language: en-US
Subject: Re: [bitcoin-dev] Removal of reject network messages from Bitcoin
	Core (BIP61)
Precedence: list

I guess then the best way to discover nodes that have reject messages
enabled is connecting/disconnecting to random nodes and send them
invalid transactions and keep the ones which reply with a reject message.


On 18/10/2019 22.53, John Newbery via bitcoin-dev wrote:
>> Is there a NODE_* bit we can use to pick peers that support this
> (useful!) feature?
> 
> No. BIP 61 has no mechanism for advertising that a node will send REJECT
> messages.
> 
> On Wed, Oct 16, 2019 at 12:43 PM John Newbery <john@johnnewbery.com
> <mailto:john@johnnewbery.com>> wrote:
> 
>     Following discussion on this mailing list, support for BIP 61 REJECT
>     messages was not removed from Bitcoin Core in V0.19. The behaviour
>     in that upcoming release is that REJECT messages are disabled by
>     default and can be enabled using the `-enablebip61` command line option.
> 
>     Support for REJECT messages will be removed entirely in Bitcoin Core
>     V0.20, expected for release in mid 2020. The PR to remove support
>     was merged into Bitcoin Core's master branch this week.
> 
>     Adoption of new Bitcoin Core versions across reachable nodes
>     generally takes several months.
>     https://bitnodes.earn.com/dashboard/?days=365 shows that although
>     v0.18 was released in May 2019, there are still several hundred
>     reachable nodes on V0.17, V0.16, V0.15 and earlier software.
>     Software that currently use REJECT messages from public nodes for
>     troubleshooting issues therefore have plenty of time to transition
>     to one of the methods listed by Marco in the email above.
> 
>     John
> 
>     On Tue, Mar 5, 2019 at 10:28 PM Marco Falke via bitcoin-dev
>     <bitcoin-dev@lists.linuxfoundation.org
>     <mailto:bitcoin-dev@lists.linuxfoundation.org>> wrote:
> 
>         Bitcoin Core may send "reject" messages as response to "tx",
>         "block" or
>         "version" messages from a network peer when the message could
>         not be accepted.
> 
>         This feature is toggled by the `-enablebip61` command line
>         option and has been
>         disabled by default since Bitcoin Core version 0.18.0 (not yet
>         released as of
>         time of writing). Nodes on the network can not generally be
>         trusted to send
>         valid ("reject") messages, so this should only ever be used when
>         connected to a
>         trusted node. At this time, I am not aware of any software that
>         requires this
>         feature, and I would like to remove if from Bitcoin Core to make
>         the codebase
>         slimmer, easier to understand and maintain. Let us know if your
>         application
>         relies on this feature and you can not use any of the
>         recommended alternatives:
> 
>         * Testing or debugging of implementations of the Bitcoin P2P
>         network protocol
>           should be done by inspecting the log messages that are
>         produced by a recent
>           version of Bitcoin Core. Bitcoin Core logs debug messages
>           (`-debug=<category>`) to a stream (`-printtoconsole`) or to a file
>           (`-debuglogfile=<debug.log>`).
> 
>         * Testing the validity of a block can be achieved by specific RPCs:
>           - `submitblock`
>           - `getblocktemplate` with `'mode'` set to `'proposal'` for
>         blocks with
>             potentially invalid POW
> 
>         * Testing the validity of a transaction can be achieved by
>         specific RPCs:
>           - `sendrawtransaction`
>           - `testmempoolaccept`
> 
>         * Wallets should not use the absence of "reject" messages to
>         indicate a
>           transaction has propagated the network, nor should wallets use
>         "reject"
>           messages to set transaction fees. Wallets should rather use
>         fee estimation
>           to determine transaction fees and set replace-by-fee if
>         desired. Thus, they
>           could wait until the transaction has confirmed (taking into
>         account the fee
>           target they set (compare the RPC `estimatesmartfee`)) or
>         listen for the
>           transaction announcement by other network peers to check for
>         propagation.
> 
>         I propose to remove "reject" messages from Bitcoin Core 0.19.0
>         unless there are
>         valid concerns about its removal.
> 
>         Marco
>         _______________________________________________
>         bitcoin-dev mailing list
>         bitcoin-dev@lists.linuxfoundation.org
>         <mailto:bitcoin-dev@lists.linuxfoundation.org>
>         https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
> 
> 
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>