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Calling NSA to find your encryption key after a few bits were flipped (2010)

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Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#71

Post by hedora »

nix23 wrote: post #35
daniel-cussen wrote: post #22

Earlier quoted context omitted.

I have super bivalent opinions about Intel. This is the opposite of ambivalent, it means heavily charged in both directions, but cancellation is not allowed. So that's why they should have let all their chips do ECC instead of making it a premium feature, it would have been better for their brand as "Chipzilla" and had no real cost. And it's dangerous! In fact a soft-error at sea level killed an operating system upda…

It's your error, having a system with important data no actual/realtime backup no second system and no plan to recover from a failed update and no ecc is YOUR error alone. However, intel should have made ecc the standard and not just for 1000$+ Xeons.

It's turtles all the way down, sadly.

The bitflip could have hit an OS distribution service. Yes, the target machines should check the checksum, but the distribution service could have flipped the bit before the checksum was computed.

But, yeah, ECC should be the standard. Also, Intel should be better about documenting where they've left holes in their online checksums, machine check exception implementations, etc.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#72

Post by hedora »

willis936 wrote: post #18
cube00 wrote: post #14

This is what worries me about the current push that all backups including the off site tape vault must be encrypted at rest. Any problem with the de-encryption and your data is toast.

This is taken care of at the filesystem level.

That's physically impossible. Silent corruption can always happen between the point in time when the data is generated and when the filesystem checksums it.

Modern hardware tries to detect these sorts of things and halt before the corruption is propagated. Sometimes it succeeds, sometimes it does not.

The best checksums can reliably do is point at the software/hardware component that is at fault.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#73

Post by ClumsyPilot »

nix23 wrote: post #35
daniel-cussen wrote: post #22

Earlier quoted context omitted.

I have super bivalent opinions about Intel. This is the opposite of ambivalent, it means heavily charged in both directions, but cancellation is not allowed. So that's why they should have let all their chips do ECC instead of making it a premium feature, it would have been better for their brand as "Chipzilla" and had no real cost. And it's dangerous! In fact a soft-error at sea level killed an operating system upda…

It's your error, having a system with important data no actual/realtime backup no second system and no plan to recover from a failed update and no ecc is YOUR error alone. However, intel should have made ecc the standard and not just for 1000$+ Xeons.

"It's your error, having a system with important data no actual/realtime backup"

Have you ever taken picture of anything important with your phone, like a crime, or a car accident? Have you ever called 911 or sent money?

How dare you use an unreliabke system without ECC, what if a random bitflip would cause it to send 10x more money or data woupd be lost without realtime backup!

This disrespect to users and wanky attitude is the cardinal sin of our industry, people's lives are at stake and it's their fault for trusting us.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#74

Post by bcrosby95 »

ClumsyPilot wrote: post #73
nix23 wrote: post #35

Earlier quoted context omitted.

It's your error, having a system with important data no actual/realtime backup no second system and no plan to recover from a failed update and no ecc is YOUR error alone. However, intel should have made ecc the standard and not just for 1000$+ Xeons.

"It's your error, having a system with important data no actual/realtime backup" Have you ever taken picture of anything important with your phone, like a crime, or a car accident? Have you ever called 911 or sent money? How dare you use an unreliabke system without ECC, what if a random bitflip would cause it to send 10x more money or data woupd be lost without realtime backup! This disrespect to users and wanky att…

You're unlikely to notice a single bit flip in a picture you take.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#75

Post by thehappypm »

sodality2 wrote: post #43
yeetsfromhellL2 wrote: post #16

Earlier quoted context omitted.

To protect against bit flips in car fly-by-wire systems, each signal is sent three times with the 2/3 majority making the decision. This happened after the runaway Prius fiasco that may have been caused by a gamma ray. Prior to that incident the fly-by-wire system only sent one signal.

This is really inefficient, two bitflips in the same location will result in a bitflip. For 3x the space surely there's a more resilient scheme that can handle more.

All error correction and detection are designed with an acceptable probability of error in mind, which depends on the medium. For example, if you know cosmic rays might flip 1 in a million bits, and you want your system to have 1 error per trillion bits, then you need to send every bit twice to be able to detect a one-in-a-million error.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#76

Post by ip26 »

clysm wrote: post #24
benob wrote: post #21

Is there a way to embed redundancy in a crypto key so that another key a few bits away can still decrypt the data?

DES (and TDES) has 1 parity bit for every 7 bits of key. Nobody really uses it as far as I've seen (e.g. they just generate random keys with invalid parity), but it's built in to the key itself.

Parity only tells you the key is corrupt, it can't correct the block :/

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#77

Post by nopenopenopeno »

bcrosby95 wrote: post #74
ClumsyPilot wrote: post #73

Earlier quoted context omitted.

"It's your error, having a system with important data no actual/realtime backup" Have you ever taken picture of anything important with your phone, like a crime, or a car accident? Have you ever called 911 or sent money? How dare you use an unreliabke system without ECC, what if a random bitflip would cause it to send 10x more money or data woupd be lost without realtime backup! This disrespect to users and wanky att…

You're unlikely to notice a single bit flip in a picture you take.

unless it gives the killer the same mole that you have on the back of your neck

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#78

Post by trinovantes »

codeflo wrote: post #12

Bit flips are scary even on Earth. At a previous job, we had a customer who suddenly couldn’t send us email anymore. When their IT sent us the server logs to “prove” it’s our fault, we saw that the one letter in the cached MX record was wrong. This was puzzling, until I looked at the ASCII table to verify that the difference was exactly one bit. We never found out where in the name resolution process the bit got flip…

It's scary to think an election can be flipped due to cosmic rays

https://en.wikipedia.org/wiki/Electronic_voting_in_Belgium

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#79

Post by jagger27 »

bcrosby95 wrote: post #74
ClumsyPilot wrote: post #73

Earlier quoted context omitted.

"It's your error, having a system with important data no actual/realtime backup" Have you ever taken picture of anything important with your phone, like a crime, or a car accident? Have you ever called 911 or sent money? How dare you use an unreliabke system without ECC, what if a random bitflip would cause it to send 10x more money or data woupd be lost without realtime backup! This disrespect to users and wanky att…

You're unlikely to notice a single bit flip in a picture you take.

I just tested this on a JPEG. Flipping any bit in the first few bytes of a JPEG renders it unopenable on my Fedora system. I get that it's just a header and could probably be fixed, but there are consequences for bitflips, even on images.

Re: Calling NSA to find your encryption key after a few bits were flipped (2010)

#80

Post by nopenopenopeno »

ClumsyPilot wrote: post #73
nix23 wrote: post #35

Earlier quoted context omitted.

It's your error, having a system with important data no actual/realtime backup no second system and no plan to recover from a failed update and no ecc is YOUR error alone. However, intel should have made ecc the standard and not just for 1000$+ Xeons.

"It's your error, having a system with important data no actual/realtime backup" Have you ever taken picture of anything important with your phone, like a crime, or a car accident? Have you ever called 911 or sent money? How dare you use an unreliabke system without ECC, what if a random bitflip would cause it to send 10x more money or data woupd be lost without realtime backup! This disrespect to users and wanky att…

I strictly use Xeon processors for online banking for this reason.
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