Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id E2875DBB for ; Mon, 3 Jun 2019 12:56:54 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-io1-f42.google.com (mail-io1-f42.google.com [209.85.166.42]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 79041A3 for ; Mon, 3 Jun 2019 12:56:54 +0000 (UTC) Received: by mail-io1-f42.google.com with SMTP id i10so4260559iol.13 for ; Mon, 03 Jun 2019 05:56:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=blockstream.io; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=HFdIvjZE4xOr7kR5Q5Ghth/pC/TKOhN1joWhsOryjEw=; b=KtJaojyACxaIKFwF0A0GRun7oBe5ica9zVfKbY8ZwgNoPAjV+PFwwGeSY3GS+++ULC yjEIML+/FmyskhMX/P+19BcK4Y53PEx3CkqbA1eShjE2XLDxklKs3Chq+kLbdu6IuM4y 7alsVZw3/Zkvh7qbdm7PuQfDq/fvZzEhTb9vE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=HFdIvjZE4xOr7kR5Q5Ghth/pC/TKOhN1joWhsOryjEw=; b=J857eH5DjIAyVMbFz8KYwCPKRSbT8gIW5wIpKK9pYNax0HPmxARbCZNrvMrhGvPCT7 Xbp3G+j5wFkaQdH4xxCQt06qPUHQQuDCeGRGUGmR/kzVe7jQ2jpWOaL0ZRYYCLWPh3w8 /4aHeRxaw92x254XqoTVIg9F6U5Je06bYc3UJAKJ/lLA+ukZ6x+Vl77y+jtjiibS6Uko j1g86Xo0JRt2sTiG20ox00vPHUNxzb70LBC+byfTMUb3AofMyKCXEEEQ6gGREs802RmD nO7NFLhnL6PUVWInZdrSK0wcsVSVvULQKYODoBgGjFaoQmS0ftakyfrqbYYKbV0JFFJ7 lQvA== X-Gm-Message-State: APjAAAX1EtqOzeqyg6tjn4lWEMGl2jDgcmH8qvJfNMe2QdDdjEU0Y2rl ZjRVTUQyexCK+/73lTCxOrBK9fqjg+bEre0EBw7J8cga X-Google-Smtp-Source: APXvYqyHW2zNmZsKgrhrbY7/UYbnPIl3htryd5NFNV1OViCPK33L2av6FQ4ozn2dfGM+JU9qA92J+NaR7IoxwQZ38fE= X-Received: by 2002:a5d:94d7:: with SMTP id y23mr16083585ior.296.1559566613503; Mon, 03 Jun 2019 05:56:53 -0700 (PDT) MIME-Version: 1.0 References: <871s0c1tvg.fsf@rustcorp.com.au> In-Reply-To: <871s0c1tvg.fsf@rustcorp.com.au> From: "Russell O'Connor" Date: Mon, 3 Jun 2019 08:56:42 -0400 Message-ID: To: Rusty Russell , Bitcoin Protocol Discussion Content-Type: multipart/alternative; boundary="00000000000000730f058a6ae660" X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HTML_MESSAGE, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Mon, 03 Jun 2019 15:10:25 +0000 Subject: Re: [bitcoin-dev] [PROPOSAL] Emergency RBF (BIP 125) 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: Mon, 03 Jun 2019 12:56:55 -0000 --00000000000000730f058a6ae660 Content-Type: text/plain; charset="UTF-8" Hi Rusty, On Sun, Jun 2, 2019 at 9:21 AM Rusty Russell via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > The new "emergency RBF" rule: > > 6. If the original transaction was not in the first 4,000,000 weight > units of the fee-ordered mempool and the replacement transaction is, > rules 3, 4 and 5 do not apply. > > This means: > > 3. This proposal does not open any significant new ability to RBF spam, > since it can (usually) only be used once. IIUC bitcoind won't > accept more that 100 descendents of an unconfirmed tx anyway. > Is it not possible for Alice to grief Bob's node by alternating RBFing two transactions, each one placing itself at the bottom of Bob's top 4,000,000 weight mempool which pushes the other one below the top 4,000,000 weight, and then repeating with the other transaction? It might be possible to amend this proposal to partially mitigate this. --00000000000000730f058a6ae660 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Rusty,

On Sun, Jun 2, 2019 at 9:21 AM Rusty Rus= sell via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:
The new "emergency RBF" rule:

=C2=A06. If the original transaction was not in the first 4,000,000 weight<= br> =C2=A0 =C2=A0 units of the fee-ordered mempool and the replacement transact= ion is,
=C2=A0 =C2=A0 rules 3, 4 and 5 do not apply.

This means:

3. This proposal does not open any significant new ability to RBF spam,=
=C2=A0 =C2=A0since it can (usually) only be used once.=C2=A0 IIUC bitcoind = won't
=C2=A0 =C2=A0accept more that 100 descendents of an unconfirmed tx anyway.<= br>

Is it not possible for Alice to grief B= ob's node by alternating RBFing two transactions, each one placing itse= lf at the bottom of Bob's top 4,000,000 weight mempool which pushes the= other one below the top 4,000,000 weight, and then repeating with the othe= r transaction?=C2=A0 It might be possible to amend this proposal to partial= ly mitigate this.
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