diff options
| author | Gregory Maxwell <gmaxwell@gmail.com> | 2015-07-20 20:55:57 +0000 |
|---|---|---|
| committer | bitcoindev <bitcoindev@gnusha.org> | 2015-07-20 20:55:58 +0000 |
| commit | 3e2189f2bf6c0a4fa846dd628f2be8b1b8afe8be (patch) | |
| tree | c0892d956e40aebf643fae1cb9fcbc54d1d92acf | |
| parent | 945c8fcec375dd14a9db82f4badb675786aadee6 (diff) | |
| download | pi-bitcoindev-3e2189f2bf6c0a4fa846dd628f2be8b1b8afe8be.tar.gz pi-bitcoindev-3e2189f2bf6c0a4fa846dd628f2be8b1b8afe8be.zip | |
Re: [bitcoin-dev] For discussion: limit transaction size to mitigate CVE-2013-2292
| -rw-r--r-- | 62/9d4d92b0e762e48929712a3fbbfbe79eb03919 | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/62/9d4d92b0e762e48929712a3fbbfbe79eb03919 b/62/9d4d92b0e762e48929712a3fbbfbe79eb03919 new file mode 100644 index 000000000..83ad1b11a --- /dev/null +++ b/62/9d4d92b0e762e48929712a3fbbfbe79eb03919 @@ -0,0 +1,76 @@ +Return-Path: <gmaxwell@gmail.com> +Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org + [172.17.192.35]) + by mail.linuxfoundation.org (Postfix) with ESMTPS id EAB2C45E + for <bitcoin-dev@lists.linuxfoundation.org>; + Mon, 20 Jul 2015 20:55:58 +0000 (UTC) +X-Greylist: whitelisted by SQLgrey-1.7.6 +Received: from mail-ig0-f169.google.com (mail-ig0-f169.google.com + [209.85.213.169]) + by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 72D3D1DB + for <bitcoin-dev@lists.linuxfoundation.org>; + Mon, 20 Jul 2015 20:55:58 +0000 (UTC) +Received: by igbij6 with SMTP id ij6so92184019igb.1 + for <bitcoin-dev@lists.linuxfoundation.org>; + Mon, 20 Jul 2015 13:55:57 -0700 (PDT) +DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; + h=mime-version:in-reply-to:references:date:message-id:subject:from:to + :cc:content-type; + bh=emXbbGpZ3rIKEKi08HZqYhJ8+PAmgV5+FNjyImPCHxg=; + b=jp0ebZx9ktLKn/ow4Plm5s+EwhuyS7y0DoJWgTrfcn0DSPj0Uz2zHZd/YEb+eapwgv + SmFVBMloB15YJ5W5kmtQFqDl/srWNX7vdn7gytv7u/6RG4Pqj4/81aQzLHCiBJDA7smW + Xx70io/F1gKzsyeR1rTPejCJLnzZxZ3twryRThlR5EdCLpPo323sdpdFdVNYIWnQxrwV + GC36shG+RbiwU4BHCtO4BFnY4r6VtvVqiB2/t4m55QruSogg9ZesbzzS0dpb0vtYcU8v + mVWFUwL8o9xQLk2N4ZFYivwxBcQNctYsgGcIZmDJvDroBSb0scyBacy/QOVe43ba+cGE + e0wg== +MIME-Version: 1.0 +X-Received: by 10.50.39.114 with SMTP id o18mr16994056igk.75.1437425757912; + Mon, 20 Jul 2015 13:55:57 -0700 (PDT) +Received: by 10.107.48.212 with HTTP; Mon, 20 Jul 2015 13:55:57 -0700 (PDT) +In-Reply-To: <CABsx9T30aUx+Leb2HXx2QrMT8R_eTXV9hiC99av957645iQm1Q@mail.gmail.com> +References: <CABsx9T30aUx+Leb2HXx2QrMT8R_eTXV9hiC99av957645iQm1Q@mail.gmail.com> +Date: Mon, 20 Jul 2015 20:55:57 +0000 +Message-ID: <CAAS2fgRBa47ye-ouV2jDe16MJFCKxYh0zF0Jw4BTwzpXVKgwOg@mail.gmail.com> +From: Gregory Maxwell <gmaxwell@gmail.com> +To: Gavin Andresen <gavinandresen@gmail.com> +Content-Type: text/plain; charset=UTF-8 +X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, + DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, + RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 +X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on + smtp1.linux-foundation.org +Cc: bitcoin-dev@lists.linuxfoundation.org +Subject: Re: [bitcoin-dev] For discussion: limit transaction size to + mitigate CVE-2013-2292 +X-BeenThere: bitcoin-dev@lists.linuxfoundation.org +X-Mailman-Version: 2.1.12 +Precedence: list +List-Id: Bitcoin Development Discussion <bitcoin-dev.lists.linuxfoundation.org> +List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> +List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> +List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> +List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> +List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> +X-List-Received-Date: Mon, 20 Jul 2015 20:55:59 -0000 + +On Mon, Jul 20, 2015 at 7:10 PM, Gavin Andresen via bitcoin-dev +<bitcoin-dev@lists.linuxfoundation.org> wrote: +> Mitigate a potential CPU exhaustion denial-of-service attack by limiting +> the maximum size of a transaction included in a block. + +This seems like a fairly indirect approach. The resource being watched +for is not the size (otherwise two transactions for 200k would be +strictly worse than one 200k transactions) but the potential of N^2 +costs related to repeated hashing in checksig; which this ignores. + +The cost of the indirection is forclosing future applications which +involve larger signatures but have no quadratic component and are thus +fast to verify-- or requring yet another hard fork to remove the +limit, or a kludgy soft fork that splits the same data across two +"transactions" which get processed as a unit... all would be +unfortunate. + +Alternative 1 sounds more attractive to be for this reason as it's more direct. + |