What is the biggest attack in GBPS you stopped
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Tell me how 30k pps of blocked traffic that was not being logged constitutes as a DDOS that will consume all resources of my entire box? I've done 70k pps ping floods against my firewall and it only consumes 5% cpu and nothing is affected. That ping flood is 0 packets dropped, max ping 10ms, avg ping 0.2ms.
But when he does a 30k pps of blocked TCP+UDP traffic, my box goes to crap and my admin interface goes offline to the point PFSense does not respond to ARP. And my admin interface isn't even the interface being hit, it's the WAN interface! They don't even share the same physical interface
Two things: increase your state table to 8M states. The UI and the rest of the box will be fine.
Second, the underlying issue is an IRQ interrupt flood. I'm not going to rehash it here, but it's the em driver flooding the CPU with interrupts. That's why only one core goes to 100%.
I've points this out several times on this thread, go back several pages to see my data an analysis. That's the root cause. Everything else on this thread is noise.
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@cmb:
I thought DTrace was getting nowhere because it requires ESF to include it in the version of freebsd they use with pfsense?
You need more than just dtrace, various other debug options like PMC, and it needs to be replicated on stock FreeBSD with as basic of a test case as possible.
I'll check out PMC as this is something I'm not familiar with or may know it by another name.
We're not holding anything up there if someone wants to do it right.
Not suggesting you /ESF are holding things up, but I was a bit surprised to find out that something like dtrace wasnt shipped as I recognise some things stock in freebsd is not needed for a pfsense/fw type of role or application, which then makes sense to not include in pfsense image, but imo Dtrace is useful especially when considering things like this. http://www.cybergrandchallenge.com/
Doing it right doesn't involve "watch my Youtube videos of what happens when I have a criminal botnet hit me with traffic I won't describe, using an undocumented configuration that's full of sub-optimal settings for standing up to resource exhaustion attacks."
I dont have enough data to know if it was criminal or not, but one way of looking at the use of criminal botnets is theres nothing like a real world test in some respects.
So it's clear what's being done, the end result, and how to replicate. There's no big secret in how to run a large scale SYN flood where the world would end if it was put out there.
@cmb:
It's all doable with hping or other tools. Supermule uses shady illegal services you pay for in Bitcoin that use criminal-run botnets. The same circumstance can be lab replicated without paying criminals.
Investigating this further is still on my radar. There have just been real problems that affect many reasonable real world use cases that have taken precedence. Anyone trying to stop DDoS with a firewall of any type is doing it wrong.
I havent been able to replicate yet internally which is why I'm taking a different approach atm before I get SM to hit me up again.
Bitcoins can be traced http://www.theguardian.com/technology/2013/oct/07/fbi-bitcoin-pranked-silk-road fwiw.
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Two things: increase your state table to 8M states. The UI and the rest of the box will be fine.
Doesn't that require about 8GB of RAM? Who has that in their firewall?
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It actually takes 16GB to do that if all 8M is used.
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Who has that in their firewall?
RAM is cheap at this times 4 x 8 GB of ECC RAM is really payable for the masses, and why not?
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@KOM:
Two things: increase your state table to 8M states. The UI and the rest of the box will be fine.
Doesn't that require about 8GB of RAM? Who has that in their firewall?
I have 4GB of RAM and it worked without a hitch. Memory utilization was actually very low, <50% I believe. The raw data is buried somewhere in this thread.
I think, but cannot recall specifically, that it only hit about 4.7M states at the top end before the IRQ interrupt storm warning started. That's also why I think the state table never filled up.
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So you are not sure??
Just because I pissed you off…
I thought you were older than the "name calling" age.
Tell me what I used... And since you have offered little to no help at all in configuring these "sub optimal" configurations, its very clear to everybody that nothing good comes from ESF other than bickering and "sub optimal" communication.
If I really DDoS'ed you then you wouldnt be online yet.
@cmb:
@KOM:
So we can't expect the pfSense team to fix a problem that's not in pfSense, and they are at the mercy of the FreeBSD code releases.
While we can't expect them to, they certainly have fixed some FreeBSD bugs and submitted the patches upstream, which were accepted for inclusion by the FreeBSD team.
Yup. And if there were truly a world-is-ending issue here, we'd already have done the same already.
All firewalls require some degree of tuning to stand up to resource exhaustion attacks. Settings appropriate for such circumstances aren't defaults because they would break many more circumstances than they would help, as they're too aggressive for many VoIP configurations, among other possible problems. Also general default behaviors that most people want, like logging all blocked traffic, are really terrible in that circumstance. Among a variety of other problems I've pointed out with the scenarios in these threads.
I've seen enough of Supermule's super-secret DDoS stuff from when he DDoSed our forum several times (not going to believe it wasn't him), and some things I've gathered from others, to be able to put together a proper analysis to get upstream at some point.
It's all doable with hping or other tools. Supermule uses shady illegal services you pay for in Bitcoin that use criminal-run botnets. The same circumstance can be lab replicated without paying criminals.
Investigating this further is still on my radar. There have just been real problems that affect many reasonable real world use cases that have taken precedence. Anyone trying to stop DDoS with a firewall of any type is doing it wrong.
Brian, this is unacceptable.
Final warning. Be nice, or you are banned from this forum.
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I am nice.
But you would be pissed as well if you were accused of things you didnt do.
It goes both ways.
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How much power does the cycling monkey have?
Can it beat Chris Froome?
Should I hire it to pedal on the back of my tandem?I'll admit my shell scripts can't (yet?) pedal a bike. :)
You hired a power-cycling monkey?
No, I wrote one. :D
Borrowing the chaos monkey name.
Just scripting SNMP sets against an IP PDU to effectively yank the power plug, power it back up, wait for it to reply to pings, rinse and repeat. Many thousands of times. One box close to 20,000 times now, one over 10,000 times, others well into the thousands.
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Come on guys…
Clearly there is an issue and it
s not only caused by resource exaustion as cmb says. Mine went down with 3Mbps of traffic and I have 40/100 and 20/20 pipes. Everything went down and he didnt even touch my internal webserver but firewall itself.Why can
t you work together, Im really dissapointed in the way things went on this issue.pfSense is really cool and serious project and forums didn`t let me down since I first posted here (ok besides dok and his sarcasm which I got used to and it amuses me every time hehe ;) ) but I always got help or at least hint where to start.
Open source guys…
My 2c...
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I am nice.
But you would be pissed as well if you were accused of things you didnt do.
It goes both ways.
You may have been falsely accused. How you react to this is your choice.
There is a difference that seems to need need stating:
Chris is a co-owner, as am I. You are a guest.
While you are helpful, and respectful, you are welcome here. When that is no longer true, I will (and take this with all the requisite gravitas), remove you from this community. You will not return. I removed my former persona ("gonzopancho") in a way that I could not ever recover, because I found that I could no longer respond in a reasonable manner.
You have been far over "the line" of reasonable response on many occasions. This is your final warning. How you react is your choice.
I think you have value that you can bring, but your behavior in this and other things is, in the balance, largely negative toward the project and its owners.
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Come on guys…
Clearly there is an issue and it
s not only caused by resource exaustion as cmb says. Mine went down with 3Mbps of traffic and I have 40/100 and 20/20 pipes. Everything went down and he didnt even touch my internal webserver but firewall itself.Why can
t you work together, Im really dissapointed in the way things went on this issue.pfSense is really cool and serious project and forums didn`t let me down since I first posted here (ok besides dok and his sarcasm which I got used to and it amuses me every time hehe ;) ) but I always got help or at least hint where to start.
Open source guys…
My 2c...
The issue is resource exhaustion. The 'attack' (as it were) runs pf out of states. It is not (as some seem to want to state) related to virtualization or (as others seem to want to state) interrupt load on a single CPU.
To my knowledge, Brian has never shared his scripts/code, but we do have what I believe to be similar internally. We have shown (internally)
that the problem is endemic to the pf in FreeBSD. It is not specific to pfSense, or any 'forks' of same. I have not verified that the problem occurs on OpenBSD, or another 'stateful' firewall.The problem is not made worse by the lack of dtrace on the image.
Your disappointment is not inducement to work on the problem, nor am I aware of what you mean by "Open source guys…"
We, or someone else, will eventually fix the issue. It may be quite difficult. The pf codebase is not well-structured.
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Thing is Chris… Franco is very kind to people.
I dont really dig into the opnsense/pfsense feud since its meaningless.
I see. So is your assertion is that Brian/Supermule on forum.opnsense.org is not the same as Brian/Supermule on forum.pfsense.org?
Because if these are the same, then you said something quite different only two weeks ago:
https://forum.opnsense.org/index.php?topic=581.msg2799#msg2799
I take several issues with what you said:
Issue IMHO is that pfSense is nothing more than a name and logo.
I assert that this is false.
All the code and contributions are open source
This is true, and always has been.
and they want to change that so they can make money of other peoples work and contributions.
We have not changed that pfSense is open source, nor do we "want to change that". Your ugly accusation is false, Brian.
I dont like it and thats why I am here.
This is, of course, your choice, but I don't see why you feel allowed to be two-faced about it without challenge.
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Its not. Plenty of ressources left as you can see. Its routing and the way pf handles it.
The issue is different.
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OK, so 45 forum pages later, we have determined that there is a problem in pf that may or may not get fixed by someone sometime, perhaps.
Can we close this thread now already?
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Regardless of whether or not this low bandwidth DDOS traffic should be stopped upstream, 3 mbps of any kind of traffic should not render a modern business class firewall useless. Period.
The root issue being in FreeBSD pf doesn't changes that. And since pfSense is built on FreeBSD it is by extension a pfSense problem too.
What specific work has the pfSense project done with the FreeBSD project to resolve this specific issue and provide a fix?
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Regardless of whether or not this low bandwidth DDOS traffic should be stopped upstream, 3 mbps of any kind of traffic should not render a modern business class firewall useless. Period.
The root issue being in FreeBSD pf doesn't changes that. And since pfSense is built on FreeBSD it is by extension a pfSense problem too.
What specific work has the pfSense project done with the FreeBSD project to resolve this specific issue and provide a fix?
I outlined what we've done above. We have, what I believe to be, a similar program which can cause a similar issue.
If we develop a fix, we will attempt to upstream it to FreeBSD.
Right now, nobody is actively working on this "issue", because it is, fundamentally, a misapplication of technology.
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@KOM:
OK, so 45 forum pages later, we have determined that there is a problem in pf that may or may not get fixed by someone sometime, perhaps.
Can we close this thread now already?
+1
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@jwt:
Regardless of whether or not this low bandwidth DDOS traffic should be stopped upstream, 3 mbps of any kind of traffic should not render a modern business class firewall useless. Period.
The root issue being in FreeBSD pf doesn't changes that. And since pfSense is built on FreeBSD it is by extension a pfSense problem too.
What specific work has the pfSense project done with the FreeBSD project to resolve this specific issue and provide a fix?
I outlined what we've done above. We have, what I believe to be, a similar program which can cause a similar issue.
If we develop a fix, we will attempt to upstream it to FreeBSD.
Right now, nobody is actively working on this "issue", because it is, fundamentally, a misapplication of technology.
Is there a bug report with freebsd so we can keep tabs on it?
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Is there a bug report with freebsd so we can keep tabs on it?
Read this post: FreeBSD/pf and SYN ACK flooding. Then you'll understand why there's no upstream bug anywhere. (Unlike here, they've been able to stop the nonsense in just a single page, not 45 and counting… ::))
