Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Lennart Poettering, Christian Brauner founded a new company

amutable.com

Post reply on HN
Print view View original

681–690 of 770 posts

Re: Lennart Poettering, Christian Brauner founded a new company

#681

Post by fc417fc802 »

charcircuit wrote: post #660
fc417fc802 wrote: post #648

Earlier quoted context omitted.

Could you please spell out the specifics of this scenario? MitM via an evil (ie incorrect) domain name is prevented because U2F (and now webauthn or CTAP2) are origin bound. RATs? On stock android? How does that work? And how are the things you describe not also threats for online banking via a browser? It's certainly not how the vast majority of attacks take place in the wild. Can you provide any examples of such an…

>are origin bound. This is assuming the user's device is not compromised. >How does that work? Priviledge escalation on an old OS version allows an attacker to get root access. Then with that they can bypass any sandboxing. Or they could get access to some android permission intended for system apps that they should not have access to and use that to do malicous things. I don't closely follow malware outbreaks for an…

So the attacker compromises the user's device ... and then sets up a MitM? This is making about as much sense as the typical Hollywood plot that involves computers so I guess that means we're on track.

> Priviledge escalation on an old OS version allows an attacker to get root access.

At which point hardware attestation accomplishes nothing. Running in an enclave might but attesting the OS image that was used to boot most certainly won't.

Many consumers use older devices. Any banking app is forced to support them or they will lose customers. There's no way around that. (It doesn't matter anyway because these sorts of attacks simply aren't commonplace.)

> but malware does exist.

I didn't ask for an example of malware. I asked you to point to an example of a widespread attack against secured accounts using malware as a vector. You have invented some utterly unrealistic scenario that simply isn't a concern in the real world for a consumer banking interaction.

You're describing the sort of high effort targeted attack utilizing one or more zero days that a high level government official might be subject to.

Re: Lennart Poettering, Christian Brauner founded a new company

#682

Post by NekkoDroid »

jcgl wrote: post #662
charcircuit wrote: post #594

Earlier quoted context omitted.

I hope you are mistaken. It's embarrassing how far behind in security the desktop Linux ecosystem is.

Agreed in general. But regarding secure boot, it's not like shim actually helps with real security either afaiu, right?

AFAIU (I haven't looked much into it) shim basically exists so that MS signs the shim once (or only a few times when updated), which has the distro public key embedded, which does further verification of the chain (bootloader/kernel) which gets updated more frequently.

Re: Lennart Poettering, Christian Brauner founded a new company

#683

Post by blibble »

jorvi wrote: post #523
blibble wrote: post #511

Earlier quoted context omitted.

it's a system service file the problem is systemd > The difference is that systemd is much better at ensuring correctness. yeah, whatever mate

Seems like you have an axe to grind with systemd because it replaced your familiar (but extremely cruddy) init system and now you refuse to debug the problem because you prefer being able to blame systemd. There is so much granularity and flexibility in what you can do it seems rather unlikely you cannot make it happen correctly. And if it is truly a bug... open an issue? They're rather responsive to it. And it isn't…

> Seems like you have an axe to grind with systemd because it replaced your familiar (but extremely cruddy) init system and now you refuse to debug the problem because you prefer being able to blame systemd.

I'm a pragmatist: I just want it to work

my solution to MULTIPLE different services failing to IP bind is to turn on the non-local ip binding sysctl, bypassing systemd's brokenness entirely

> There is so much granularity and flexibility in what you can do it seems rather unlikely you cannot make it happen correctly.

I've written an init before (in C), I know how the netlink interface to set an IP address and add routing table entries works

I understand the difference between monotonic and wall clocks

I understand the difference between Wants and Require

I know what's going on at every, single, level

and I can't stand how unreliable systemd makes nearly every single one of my, bluntly, completely vanilla systems

> And if it is truly a bug... open an issue?

did you read the link I pasted earlier?

I'm not wasting my time with that level of idiocy (from LP himself)

Re: Lennart Poettering, Christian Brauner founded a new company

#684

Post by jcgl »

NekkoDroid wrote: post #682
jcgl wrote: post #662

Earlier quoted context omitted.

Agreed in general. But regarding secure boot, it's not like shim actually helps with real security either afaiu, right?

AFAIU (I haven't looked much into it) shim basically exists so that MS signs the shim once (or only a few times when updated), which has the distro public key embedded, which does further verification of the chain (bootloader/kernel) which gets updated more frequently.

That's basically my understanding too. But since you can still boot any shim-supported distro, Secure Boot + shim practically gains you nothing. An adversary can simply boot their own own copy of shim with whatever OS they like.

Re: Lennart Poettering, Christian Brauner founded a new company

#685

Post by ahepp »

blacklion wrote: post #512
esjeon wrote: post #436

Earlier quoted context omitted.

Attestation is a critical feature for many H/W companies (e.g. IoT, robotics), and they struggle with finding security engineers who expertise in this area (disclaimer: I used to work as a operating system engineer + security engineer). Many distros are not only designed for desktop users, but also for industrial uses. If distros ship standardized packages in this area, it would help those companies a lot.

IoT and robotics should (dare I say "must"?) not use general-purpose OSes at all. This «Linux have a finger in every pie» attitude is very harmful for industry, IMHO.

How are you defining "general-purpose OS"? Are you saying IoT and robotics shouldn't use a Linux kernel at all? Or just not your general purpose distros? I would be interested to hear more of your logic here, since it seems like using the same FOSS operating system across various uses provides a lot of value to everyone.

Re: Lennart Poettering, Christian Brauner founded a new company

#686

Post by charcircuit »

fc417fc802 wrote: post #681
charcircuit wrote: post #660

Earlier quoted context omitted.

>are origin bound. This is assuming the user's device is not compromised. >How does that work? Priviledge escalation on an old OS version allows an attacker to get root access. Then with that they can bypass any sandboxing. Or they could get access to some android permission intended for system apps that they should not have access to and use that to do malicous things. I don't closely follow malware outbreaks for an…

So the attacker compromises the user's device ... and then sets up a MitM? This is making about as much sense as the typical Hollywood plot that involves computers so I guess that means we're on track. > Priviledge escalation on an old OS version allows an attacker to get root access. At which point hardware attestation accomplishes nothing. Running in an enclave might but attesting the OS image that was used to boot…

>At which point hardware attestation accomplishes nothing

Attestation could be used to say that the user is not using a secure version of the OS That has known vulnerabilities patched.

>Any banking app is forced to support them or they will lose customers.

Remote attestation is just one of the many signals used for detecting fraud.

>one or more zero days

Many phones are not on an OS getting security updates. Whether that be due to age or the vendor not distributing the security patches. Even using old exploits malware can work.

Re: Lennart Poettering, Christian Brauner founded a new company

#687

Post by tonoto »

sam_lowry_ wrote: post #150
blibble wrote: post #137

Earlier quoted context omitted.

that's a silver lining the anti-user attestation will at least be full of security holes, and likely won't work at all

Dunno about the others but Pottering has proven himself to deliver software against the grain.

agent Smith, the one that don't care at all about conforming to POSIX?

"In fact, the way I see things the Linux API has been taking the role of the POSIX API and Linux is the focal point of all Free Software development. Due to that I can only recommend developers to try to hack with only Linux in mind and experience the freedom and the opportunities this offers you. So, get yourself a copy of The Linux Programming Interface, ignore everything it says about POSIX compatibility and hack away your amazing Linux software. It's quite relieving!" -- https://archive.fosdem.org/2011/interview/lennart-poettering...

Re: Lennart Poettering, Christian Brauner founded a new company

#688

Post by NekkoDroid »

jcgl wrote: post #684
NekkoDroid wrote: post #682

Earlier quoted context omitted.

AFAIU (I haven't looked much into it) shim basically exists so that MS signs the shim once (or only a few times when updated), which has the distro public key embedded, which does further verification of the chain (bootloader/kernel) which gets updated more frequently.

That's basically my understanding too. But since you can still boot any shim-supported distro, Secure Boot + shim practically gains you nothing. An adversary can simply boot their own own copy of shim with whatever OS they like.

> An adversary can simply boot their own own copy of shim with whatever OS they like.

They'd need to get MS to sign it first, but otherwise yea. That's why I remove the MS keys on my non-windows systems.

Re: Lennart Poettering, Christian Brauner founded a new company

#689

Post by ShroudedNight »

stackghost wrote: post #602
bee_rider wrote: post #559

Earlier quoted context omitted.

I do sort of wonder if there’s room in my life for a small attested device. Like, I could actually see a little room for my bank to say “we don’t know what other programs are running on your device so we can’t actually take full responsibility for transactions that take place originated from your device,” and if I look at it from the bank’s point of view that doesn’t seem unreasonable. Of course, we’ll see if anybody…

The bank thing is a smoke screen. This entire shit storm is 100% driven by the music, film, and tv industries, who are desperate to eke a few more millions in profit from the latest Marvel snoozefest (or whatever), and who tried to argue with a straight face that they were owed more than triple the entire global GDP [0]. These people are the enemy. They do not care about about computing freedom. They don't care about…

Also worth remembering that around 2010, the music and film industry associations of America were claiming entitlement to $50 billion dollars annually in piracy-related losses beyond what could be accounted for in direct lost revenue (which _might_ have been as much as 10 billion, or 1/6th of their claim):

https://youtu.be/GZadCj8O1-0

These guys pathologically have had a chip on their shoulder since Napster.

Re: Lennart Poettering, Christian Brauner founded a new company

#690

Post by jcgl »

NekkoDroid wrote: post #688
jcgl wrote: post #684

Earlier quoted context omitted.

That's basically my understanding too. But since you can still boot any shim-supported distro, Secure Boot + shim practically gains you nothing. An adversary can simply boot their own own copy of shim with whatever OS they like.

> An adversary can simply boot their own own copy of shim with whatever OS they like. They'd need to get MS to sign it first, but otherwise yea. That's why I remove the MS keys on my non-windows systems.

I don't know all the ins and outs, but because of the Machine Owner Key (MOK) mechanism in shim, it should be possible to boot arbitrary OSes without MS signing anything.

Your step of removing the MS keys works of course :) Although I've heard that can be risky on various systems that need to load MS-signed EEPROMS. Also I think that firmware updates can be problematic?

Post reply on HN