4 ms·

This is such a bad take. I'd love the easy ability to run confidential computing loads with fine grained control over the data it gets access to. You can do th

by nl 3y ago

This is such a bad take. I'd love the easy ability to run confidential computing loads with fine grained control over the data it gets access to. You can do this now on the desktop using SGX (etc) but on mobile it's really hard. As a specific example of this, it'd be great to be able to run Whisper continually and have strong, system level guarantees about what can read the data.

refulgentis 3y ago
I used to work at Google adjacent to this stuff and A) you wouldn't boot up a whole VM for this, on a phone, that'd be very wasteful B) there's much simpler ways to provide the same guarantee. So in general, just would avoid labeling the quality of other people's takes. You never know who is reading yours
- somanytta 3y ago
  [flagged]
- nl 3y ago
  I agree there are currently better ways of doing this (because as you mention the resource/protection trade off for this technology on this application is sub-optimal), but the context here is as an example on HN where the data privacy is obvious so I didn't have to write a whole paper explaining it.
  - refulgentis 3y ago
    Its "not even wrong", if you had a million monkeys on a million typewriters with a million trillion millenia, still, none would come up with a paper long enough to explain how that'd help anything (ex. trivially, microphone)
    - nl 3y ago
      > trivially, microphone Qualcomm has trusted input for at least touch sensors into their trusted enclave (unsure about microphone input at this point). Look for "TUI" in https://www.qualcomm.com/content/dam/qcomm-martech/dm-assets/documents/Payments-on-Enterprise-Devices.pdf https://www.qualcomm.com/content/dam/qcomm-martech/dm-assets...
      - refulgentis 3y ago
        Yes
zeusk 3y ago
is it really? wasn't that the whole point of ARM TZ/SEP?
- gjsman-1000 3y ago
  Not really. ARM TZ has been repeatedly blown open, in part because it’s not really a separate core or virtualized workload, but a different “mode of operation” that the standard CPU cores switch into temporarily. Basically going back-and-forth between TZ and your OS if I understand correctly. Turns out that’s a side-channel attack nightmare.
- saagarjha 3y ago
  This is supposed to be a replacement to TrustZone applets.
- nl 3y ago
  Trusted computing can be used for DRM. I'm much more interested in it as a privacy enhancing technology: the fact that you can have strong guarantees about what can be done with data in the enclave is useful for a lot of applications where you have sensitive data. (Putting aside the fact for the moment that most - if not all - trusted computing platforms have some security vulnerabilities. Obviously this is bad, but doesn't preclude their utility)
saagarjha 3y ago
The threat model you have in your head seems to imply that you don't trust your OS to not peek into what Whisper is doing? There are very few workloads that need or can operate under that model.
- somanytta 3y ago
  It's not really a matter of need, more a matter of good hygiene. Do you trust any modern OS not to accidently include sensitive information when it generates a crash report for an app and sends it off the some remote server in the background? Isolation is a useful tool. In an ideal world it can be done perfectly at the OS level, but we don't live in that world.
  - saagarjha 3y ago
    I agree that being able to isolate things that have different security domains is a useful tool. That said, I am not really seeing how pKVM provides useful primitives for much other than DRM, which has historically been the primary usecase for trusted execution that isolated VMs seem to provide.
    - somanytta 3y ago
      Consider that, I want to be able to use a regular android OS, but I don't completely trust it, either its purposely malicious or just accidently going to leak info. So isolation is good in this case, its much easier to audit the mechanism of isolation rather than the whole OS. The problem with DRM and "trusted computing" part is that it's under someone else's control, some central authority etc. From my reading of the docs on this, this is not the case with pVM, from https://source.android.com/docs/core/virtualization/security https://source.android.com/docs/core/virtualization/security > Data is tied to instances of a pVM, and secure boot ensures that access to an instance’s data can be controlled > When a device is unlocked with fastboot oem unlock, user data is wiped. > Once unlocked, the owner of the device is free to reflash partitions that are usually protected by verified boot, including partitions containing the pKVM implementation. Therefore, pKVM on an unlocked device won't be trusted to uphold the security model. So my reading of this is that that it is under the users control, as long as they have the ability to unlock the bootloader, and reflash the device with their own images. I'd love someone who is more knowledgeable to weigh in, but this tech, to me, doesn't seem that close to TPM/DRM type chips where there is no possibility of user control.
fuomag9 3y ago
Btw SGX has been removed from 11th gen desktop CPUs and onwards https://www.bleepingcomputer.com/news/security/new-intel-chips-wont-play-blu-ray-disks-due-to-sgx-deprecation/ https://www.bleepingcomputer.com/news/security/new-intel-chi...

by nl 3y ago

refulgentis 3y ago

I used to work at Google adjacent to this stuff and A) you wouldn't boot up a whole VM for this, on a phone, that'd be very wasteful B) there's much simpler ways to provide the same guarantee. So in general, just would avoid labeling the quality of other people's takes. You never know who is reading yours

somanytta 3y ago
[flagged]
nl 3y ago
I agree there are currently better ways of doing this (because as you mention the resource/protection trade off for this technology on this application is sub-optimal), but the context here is as an example on HN where the data privacy is obvious so I didn't have to write a whole paper explaining it.
- refulgentis 3y ago
  Its "not even wrong", if you had a million monkeys on a million typewriters with a million trillion millenia, still, none would come up with a paper long enough to explain how that'd help anything (ex. trivially, microphone)
  - nl 3y ago
    > trivially, microphone Qualcomm has trusted input for at least touch sensors into their trusted enclave (unsure about microphone input at this point). Look for "TUI" in https://www.qualcomm.com/content/dam/qcomm-martech/dm-assets/documents/Payments-on-Enterprise-Devices.pdf https://www.qualcomm.com/content/dam/qcomm-martech/dm-assets...
    - refulgentis 3y ago
      Yes

zeusk 3y ago

is it really? wasn't that the whole point of ARM TZ/SEP?

gjsman-1000 3y ago
Not really. ARM TZ has been repeatedly blown open, in part because it’s not really a separate core or virtualized workload, but a different “mode of operation” that the standard CPU cores switch into temporarily. Basically going back-and-forth between TZ and your OS if I understand correctly. Turns out that’s a side-channel attack nightmare.
saagarjha 3y ago
This is supposed to be a replacement to TrustZone applets.
nl 3y ago
Trusted computing can be used for DRM. I'm much more interested in it as a privacy enhancing technology: the fact that you can have strong guarantees about what can be done with data in the enclave is useful for a lot of applications where you have sensitive data. (Putting aside the fact for the moment that most - if not all - trusted computing platforms have some security vulnerabilities. Obviously this is bad, but doesn't preclude their utility)

saagarjha 3y ago

The threat model you have in your head seems to imply that you don't trust your OS to not peek into what Whisper is doing? There are very few workloads that need or can operate under that model.

somanytta 3y ago
It's not really a matter of need, more a matter of good hygiene. Do you trust any modern OS not to accidently include sensitive information when it generates a crash report for an app and sends it off the some remote server in the background? Isolation is a useful tool. In an ideal world it can be done perfectly at the OS level, but we don't live in that world.
- saagarjha 3y ago
  I agree that being able to isolate things that have different security domains is a useful tool. That said, I am not really seeing how pKVM provides useful primitives for much other than DRM, which has historically been the primary usecase for trusted execution that isolated VMs seem to provide.
  - somanytta 3y ago
    Consider that, I want to be able to use a regular android OS, but I don't completely trust it, either its purposely malicious or just accidently going to leak info. So isolation is good in this case, its much easier to audit the mechanism of isolation rather than the whole OS. The problem with DRM and "trusted computing" part is that it's under someone else's control, some central authority etc. From my reading of the docs on this, this is not the case with pVM, from https://source.android.com/docs/core/virtualization/security https://source.android.com/docs/core/virtualization/security > Data is tied to instances of a pVM, and secure boot ensures that access to an instance’s data can be controlled > When a device is unlocked with fastboot oem unlock, user data is wiped. > Once unlocked, the owner of the device is free to reflash partitions that are usually protected by verified boot, including partitions containing the pKVM implementation. Therefore, pKVM on an unlocked device won't be trusted to uphold the security model. So my reading of this is that that it is under the users control, as long as they have the ability to unlock the bootloader, and reflash the device with their own images. I'd love someone who is more knowledgeable to weigh in, but this tech, to me, doesn't seem that close to TPM/DRM type chips where there is no possibility of user control.

fuomag9 3y ago

Btw SGX has been removed from 11th gen desktop CPUs and onwards https://www.bleepingcomputer.com/news/security/new-intel-chips-wont-play-blu-ray-disks-due-to-sgx-deprecation/ https://www.bleepingcomputer.com/news/security/new-intel-chi...