Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1VAKT9-0006x5-It for bitcoin-development@lists.sourceforge.net; Fri, 16 Aug 2013 13:53:35 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.160.54 as permitted sender) client-ip=209.85.160.54; envelope-from=wtogami@gmail.com; helo=mail-pb0-f54.google.com; Received: from mail-pb0-f54.google.com ([209.85.160.54]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1VAKT8-0002kZ-2p for bitcoin-development@lists.sourceforge.net; Fri, 16 Aug 2013 13:53:35 +0000 Received: by mail-pb0-f54.google.com with SMTP id ro12so2010097pbb.41 for ; Fri, 16 Aug 2013 06:53:28 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.68.229.2 with SMTP id sm2mr1775749pbc.68.1376661208134; Fri, 16 Aug 2013 06:53:28 -0700 (PDT) Received: by 10.66.72.225 with HTTP; Fri, 16 Aug 2013 06:53:28 -0700 (PDT) In-Reply-To: References: Date: Fri, 16 Aug 2013 03:53:28 -1000 Message-ID: From: "Warren Togami Jr." To: Bitcoin Dev Content-Type: multipart/alternative; boundary=047d7b162fd7497adb04e410eafb X-Spam-Score: -0.6 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (wtogami[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1VAKT8-0002kZ-2p Subject: Re: [Bitcoin-development] Gavin's post-0.9 TODO list... X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Aug 2013 13:53:35 -0000 --047d7b162fd7497adb04e410eafb Content-Type: text/plain; charset=UTF-8 Automatic heuristic driven prioritization, with sane defaults and some configurable knobs, is exactly what I suggest. In the short-term though, any connection limits added to the client by default would be the simplest and easiest protection measure to audit. It would improve things a lot over the current situation where there are no limits, and it requires no manual intervention from node operators. Warren On Fri, Aug 16, 2013 at 3:46 AM, Mike Hearn wrote: > A ban-subnet RPC would be a reasonable addition, but obviously DoS > attackers that are IP or bandwidth constrained are really just script > kiddies. Also anything that involves every node operator doing manual > intervention rather works against decentralisation and having a big > network. That's why I keep pushing for automated heuristic driven > prioritisation. > > > On Fri, Aug 16, 2013 at 3:41 PM, Warren Togami Jr. wrote: > >> >> https://togami.com/~warren/archive/2013/example-bitcoind-dos-mitigation-via-iptables.txt >> *Anti-DoS Low Hanging Fruit: source IP or subnet connection limits* >> If you disallow the same IP and/or subnet from establishing too many TCP >> connections with your node, it becomes more expensive for attackers to use >> a single host exhaust a target node's resources. This iptables firewall >> based example has almost zero drawbacks, but it is too complicated for most >> people to deploy. Yes, there is a small chance that you will block >> legitimate connections, but there are plenty of other nodes for random >> connections to choose from. Configurable per source IP and source subnet >> limits with sane defaults enforced by bitcoind itself would be a big >> improvement over the current situation where one host address can consume >> limited resources of many target nodes. >> >> This doesn't remove the risk of a network-wide connection exhaustion >> attack by a determined attacker, but it at least makes multiple types of >> attacks a lot more expensive. This also doesn't do much against the io >> vulnerability, which would require major redesigns to prevent in Bitcoin. >> >> >> https://github.com/litecoin-project/litecoin/commit/db4d8e21d99551bef4c807aa1534a074e4b7964d >> *Want to safely delay the block size limit increase for another year or >> two?* This patch alone enables that. >> >> >> >> On Fri, Aug 16, 2013 at 2:24 AM, Mike Hearn wrote: >> >>> The only other thing I'd like to see there is the start of a new >>> anti-DoS framework. I think once the outline is in place other people will >>> be able to fill it in appropriately. But the current framework has to be >>> left behind. >>> >>> If I had to choose one thing to evict to make time for that, it'd be the >>> whitepapers. At the moment we still have plenty of headroom in block sizes, >>> even post April. It can probably be safely delayed for a while. >>> >>> >>> On Fri, Aug 16, 2013 at 2:11 PM, Mike Hearn wrote: >>> >>>> Cool. Maybe it's time for another development update on the foundation >>>> blog? >>>> >>>> >>>> On Fri, Aug 16, 2013 at 3:00 AM, Gavin Andresen < >>>> gavinandresen@gmail.com> wrote: >>>> >>>>> Mike asked what non-0.9 code I'm working on; the three things on the >>>>> top of my list are: >>>>> >>>>> 1) Smarter fee handling on the client side, instead of hard-coded >>>>> fees. I was busy today generating scatter-plots and histograms of >>>>> transaction fees versus priorities to get some insight into what miner >>>>> policies look like right now. >>>>> >>>>> 2) "First double-spend" relaying and alerting, to better support >>>>> low-value in-person transactions. Related: >>>>> *Have *a *Snack*, Pay with *Bitcoins* >>>>> >>>>> >>>>> 3) Work on 2-3 whitepapers on why we need to increase or remove the >>>>> 1MB block size limit, how we can do it safely, and go through all of the >>>>> arguments that have been made against it and explain why they're wrong. >>>>> >>>>> -- >>>>> -- >>>>> Gavin Andresen >>>>> >>>>> >>>> >>> >>> >>> ------------------------------------------------------------------------------ >>> Get 100% visibility into Java/.NET code with AppDynamics Lite! >>> It's a free troubleshooting tool designed for production. >>> Get down to code-level detail for bottlenecks, with <2% overhead. >>> Download for free and get started troubleshooting in minutes. >>> >>> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk >>> _______________________________________________ >>> Bitcoin-development mailing list >>> Bitcoin-development@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development >>> >>> >> >> >> ------------------------------------------------------------------------------ >> Get 100% visibility into Java/.NET code with AppDynamics Lite! >> It's a free troubleshooting tool designed for production. >> Get down to code-level detail for bottlenecks, with <2% overhead. >> Download for free and get started troubleshooting in minutes. >> >> http://pubads.g.doubleclick.net/gampad/clk?id=48897031&iu=/4140/ostg.clktrk >> _______________________________________________ >> Bitcoin-development mailing list >> Bitcoin-development@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/bitcoin-development >> >> > --047d7b162fd7497adb04e410eafb Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Automatic heuristic driven prioritization, with sane defau= lts and some configurable knobs, is exactly what I suggest.

<= div>In the short-term though, any connection limits added to the client by = default would be the simplest and easiest protection measure to audit. =C2= =A0It would improve things a lot over the current situation where there are= no limits, and it requires no manual intervention from node operators.
Warren






<= br>
On Fri, Aug 16, 2013 at 3:46 AM, Mike Hearn <= span dir=3D"ltr"><m= ike@plan99.net> wrote:
A ban-subnet RPC would be a= reasonable addition, but obviously DoS attackers that are IP or bandwidth = constrained are really just script kiddies. Also anything that involves eve= ry node operator doing manual intervention rather works against decentralis= ation and having a big network. That's why I keep pushing for automated= heuristic driven prioritisation.


On Fri, Aug 1= 6, 2013 at 3:41 PM, Warren Togami Jr. <wtogami@gmail.com> wr= ote:
Anti-DoS Low Hanging Fruit: source IP or subnet connection limits<= /b>
If you disallow the same IP and/or subnet from establishing too many T= CP connections with your node, it becomes more expensive for attackers to u= se a single host exhaust a target node's resources. =C2=A0This iptables= firewall based example has almost zero drawbacks, but it is too complicate= d for most people to deploy. =C2=A0Yes, there is a small chance that you wi= ll block legitimate connections, but there are plenty of other nodes for ra= ndom connections to choose from. =C2=A0Configurable per source IP and sourc= e subnet limits with sane defaults enforced by bitcoind itself would be a b= ig improvement over the current situation where one host address can consum= e limited resources of many target nodes.

This doesn't remove the risk of a network-wide conn= ection exhaustion attack by a determined attacker, but it at least makes mu= ltiple types of attacks a lot more expensive. =C2=A0This also doesn't d= o much against the io vulnerability, which would require major redesigns to= prevent in Bitcoin.

Want to safely delay the block size limit increase for anothe= r year or two? =C2=A0This patch alone enables that.



=
On Fri, Aug 16, 2013 at 2:24 AM, Mike Hearn <mike@plan99.net> wrote:
The o= nly other thing I'd like to see there is the start of a new anti-DoS fr= amework. I think once the outline is in place other people will be able to = fill it in appropriately. But the current framework has to be left behind.<= div>
If I had to choose one thing to evict to make time for that,= it'd be the whitepapers. At the moment we still have plenty of headroo= m in block sizes, even post April. It can probably be safely delayed for a = while.


On Fri, Aug 16, 2013 at 2:11 PM, Mike Hearn <mike@plan99.net> wrote:
Cool. Maybe it's time for another development update o= n the foundation blog?


On Fri, Aug 16, 2013 at 3:00 AM, Gavin Andresen <gavinandresen@gmail.com> wrote:
Mike asked what non-0.9 cod= e I'm working on; the three things on the top of my list are:

<= /div>
1) Smarter fee handling on the client side, instead of hard-coded fees= . I was busy today generating scatter-plots and histograms of transaction f= ees versus priorities to get some insight into what miner policies look lik= e right now.

2) "First double-spend" relaying and alerting= , to better support low-value in-person transactions. =C2=A0Related:=C2=A0<= /div>

Have=C2=A0a=C2=A0Snack, Pay with=C2=A0Bitcoins=C2=A0


3) Work on 2-3 whitepapers on why we need to increase o= r remove the 1MB block size limit, how we can do it safely, and go through = all of the arguments that have been made against it and explain why they= 9;re wrong.

--
--
Gavin Andresen




------------------------------------------= ------------------------------------
Get 100% visibility into Java/.NET code with AppDynamics Lite!
It's a free troubleshooting tool designed for production.
Get down to code-level detail for bottlenecks, with <2% overhead.
Download for free and get started troubleshooting in minutes.
http://pubads.g.doubleclick.net/gam= pad/clk?id=3D48897031&iu=3D/4140/ostg.clktrk
___________________= ____________________________
Bitcoin-development mailing list
Bitcoin-development@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment



-----------------------------------------------------------------------= -------
Get 100% visibility into Java/.NET code with AppDynamics Lite!
It's a free troubleshooting tool designed for production.
Get down to code-level detail for bottlenecks, with <2% overhead.
Download for free and get started troubleshooting in minutes.
http://pubads.g.doubleclick.net/gam= pad/clk?id=3D48897031&iu=3D/4140/ostg.clktrk
___________________= ____________________________
Bitcoin-development mailing list
Bitcoin-development@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment



--047d7b162fd7497adb04e410eafb--