Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 9F526E34 for ; Tue, 12 Mar 2019 17:09:02 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from blaine.gmane.org (unknown [195.159.176.226]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id EBCDE84C for ; Tue, 12 Mar 2019 17:09:01 +0000 (UTC) Received: from list by blaine.gmane.org with local (Exim 4.89) (envelope-from ) id 1h3ktf-000GsJ-Aw for bitcoin-dev@lists.linuxfoundation.org; Tue, 12 Mar 2019 18:08:59 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: bitcoin-dev@lists.linuxfoundation.org From: Andreas Schildbach Date: Tue, 12 Mar 2019 18:08:52 +0100 Message-ID: References: <78CAF294-56E2-477C-B46F-C65A56357820@sprovoost.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit 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: Content-Language: en-US X-Spam-Status: No, score=-0.3 required=5.0 tests=BAYES_00,DKIM_ADSP_ALL, RDNS_NONE autolearn=no version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Tue, 12 Mar 2019 19:45:31 +0000 Subject: Re: [bitcoin-dev] Removal of reject network messages from Bitcoin Core (BIP61) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 12 Mar 2019 17:09:02 -0000 (Posting again, since my previous reply didn't appear) On 08/03/2019 01.52, Gregory Maxwell via bitcoin-dev wrote: > That is already required because even in the presence of perfectly > honest and cooperative hosts reject messages at most can only tell you > about first-hop behaviour. It won't even tell you if the transaction > was ever even attempted to be sent to a next hop. So alternative > handling must be provided and must be reliable for the software to > work at all regardless of reject messages. > > Rejection causes were also not stable or reliable because the validity > criteria cannot generally be tested independently. For example, if a > transaction is queued due to missing a parent it isn't rejected > because missing the parent is often a temporary issue, but its feerate > cannot be measured without the parent. Later, when the parent is > obtained, the transaction can then be rejected due to feerate-- but no > reject is sent then. These two cases are understood and handled by current code. Generally the idea is take reject messages serious, but don't overrate the lack of. Luckily, network confirmations fill the gap. (Yes, a timeout is still useful. But at least it almost never happens.) > Similarly, the error state detected for things like invalid signatures > are often not very useful. The software knows that script execution > returned false, but in the general case _why_ it returned false is not > clear, and a straightforward high performance validation > implementation doesn't necessarily yield a good way of figuring out > and propagating up that information. (I think invalid signatures end > up returning a stack-nonempty state from validation currently, as an > example of that). Nevertheless, it has been proven as useful in debugging (just recently when I implemented the witness signature hash in bitcoinj). I think Wilmer Paulino summed up this point quite nicely in his reply to this thread.