4 ms·

I see that there's a lot of mindshare on privacy and "computing trust" these days. There are several approaches that I noticed. One is to not send data to untru

I see that there's a lot of mindshare on privacy and "computing trust" these days. There are several approaches that I noticed. One is to not send data to untrusted places (e.g. a server), another is to have a trust chain & hardware enclave (either through SGX / trustzone), and lastly to encrypt data (e2e encryption for transport-only, or homomorphic encryption (slow) / distributed encryption) for doing operations on the data. Currently, verifiable OSS on the server isn't in vogue (in practice or literature), but could be another approach.

formerly_proven 5y ago
> I see that there's a lot of mindshare on privacy and "computing trust" these days. This is the opposite of respecting privacy (unless you mean e.g. the privacy of DRM code), all of this stuff is "trusted" as in TCG.
- Scene_Cast2 5y ago
  Yep. Privacy is a heavily overloaded term; I meant it as a more industry-style "data access management". Some comments in the other thread do talk about non-DRM uses.
- bawolff 5y ago
  https://signal.org/blog/private-contact-discovery/ https://signal.org/blog/private-contact-discovery/ seems like an application of SGX where net privacy is increased.
  - dane-pgp 5y ago
    Or, that looks like a single point of failure that would make a good target for the government to issue a National Security Letter to Intel for.
    - xxpor 5y ago
      NSLs are a subpoena. The government can't order you to include a backdoor. Granted, they have other leverage they could use, like export licenses or purchase contracts.
      - dane-pgp 5y ago
        > The government can't order you to include a backdoor. Right, but it can order you to turn over your private keys, like it did to Lavabit[0]. Intel might instead voluntarily hand over a signed backdoored firmware, targeted at a specific set of CPUs, rather than the keys themselves, which could do more damage if the government lost control of them. Similarly I don't suppose it would be much harder for the NSA to get access to the physical servers that Signal is running its software on. Perhaps you could say that merely having the access credentials wouldn't be enough information for the NSA to take control of Signal's servers without them noticing, but any cloud provider that wants to do business with the government surely has special backdoors that make this easy, when presented with an NSL. [0] https://en.wikipedia.org/wiki/Lavabit https://en.wikipedia.org/wiki/Lavabit
    - bawolff 5y ago
      Its not perfect, but the more people in on a secret the harder it is to keep. Its much harder to have to coerce both intel and signal (even if you hack intel, you would still have to modify signal's servers from what i understand) than just signal.
    - staticassertion 5y ago
      What would that accomplish?
    - Ar-Curunir 5y ago
      It’s better than before, where all that stuff was available in plaintext
      - milkey_mouse 5y ago
        Signal didn't back up contacts and settings to their servers until they implemented "Secure Value Recovery", which relies on SGX to rate-limit guesses of a weak PIN. If SGX is broken and Signal's database falls into the wrong hands, encryption keys could be brute-forced pretty quickly (most people have 4-digit PINs).
mindslight 5y ago
It's a societal dead end, so there's no technical excitement. The same technology that would let you verify a cloud server is running code you specify, would also be used by websites to demand that your personal computing environment conforms to their whims. Imagine websites that required proprietary Google Chrome on Win/OSX on bare metal - no VM, no extensions, no third party clients, no automation, etc. Imagine mandatory ads, unsaveable images, client-side form verification, completely unaccountable code, etc. Protocols are the proper manner of allowing unrelated parties to transact at arm's length, and technologies such as remote attestation would completely destroy that.
- KirillPanov 5y ago
  > Imagine websites that required proprietary Google Chrome on Win/OSX on bare metal - no VM, no extensions, no third party clients, no automation, etc. No need to imagine, we already have that: it's called fingerprinting. Mainly via WebGL.
  - mindslight 5y ago
    There is a major difference between something being difficult/annoying, and outright impossible.
tyingq 5y ago
Memory tagging looks interesting to me. This paper from LowRISC outlines the possibilities pretty well: https://riscv.org/wp-content/uploads/2017/05/Wed0930riscv201705_ppt.pdf https://riscv.org/wp-content/uploads/2017/05/Wed0930riscv201... Referencing that not to plug RiscV, but solely because it's a good explanation. I would guess Intel, AMD, and ARM have plans or some existing work going on.
- pjmlp 5y ago
  Memory tagging is already been used successfully for years on Solaris SPARC, https://docs.oracle.com/cd/E37838_01/html/E61059/gqajs.html https://docs.oracle.com/cd/E37838_01/html/E61059/gqajs.html In what concerns ARM, all Android 11 and later versions are going to support it. https://security.googleblog.com/2019/08/adopting-arm-memory-tagging-extension.html https://security.googleblog.com/2019/08/adopting-arm-memory-... https://source.android.com/devices/tech/debug/tagged-pointers https://source.android.com/devices/tech/debug/tagged-pointer... Unfortunelly Intel's MPX was a failure, for reasons, however the rest of the CPU vendors seems to be going into the C machine model, as only way left to fix the language.
Ar-Curunir 5y ago
Verifiable OSS doesn’t stop a malicious operator from just looking at your bits in memory

formerly_proven 5y ago

> I see that there's a lot of mindshare on privacy and "computing trust" these days. This is the opposite of respecting privacy (unless you mean e.g. the privacy of DRM code), all of this stuff is "trusted" as in TCG.

Scene_Cast2 5y ago
Yep. Privacy is a heavily overloaded term; I meant it as a more industry-style "data access management". Some comments in the other thread do talk about non-DRM uses.
bawolff 5y ago
https://signal.org/blog/private-contact-discovery/ https://signal.org/blog/private-contact-discovery/ seems like an application of SGX where net privacy is increased.
- dane-pgp 5y ago
  Or, that looks like a single point of failure that would make a good target for the government to issue a National Security Letter to Intel for.
  - xxpor 5y ago
    NSLs are a subpoena. The government can't order you to include a backdoor. Granted, they have other leverage they could use, like export licenses or purchase contracts.
    - dane-pgp 5y ago
      > The government can't order you to include a backdoor. Right, but it can order you to turn over your private keys, like it did to Lavabit[0]. Intel might instead voluntarily hand over a signed backdoored firmware, targeted at a specific set of CPUs, rather than the keys themselves, which could do more damage if the government lost control of them. Similarly I don't suppose it would be much harder for the NSA to get access to the physical servers that Signal is running its software on. Perhaps you could say that merely having the access credentials wouldn't be enough information for the NSA to take control of Signal's servers without them noticing, but any cloud provider that wants to do business with the government surely has special backdoors that make this easy, when presented with an NSL. [0] https://en.wikipedia.org/wiki/Lavabit https://en.wikipedia.org/wiki/Lavabit
  - bawolff 5y ago
    Its not perfect, but the more people in on a secret the harder it is to keep. Its much harder to have to coerce both intel and signal (even if you hack intel, you would still have to modify signal's servers from what i understand) than just signal.
  - staticassertion 5y ago
    What would that accomplish?
  - Ar-Curunir 5y ago
    It’s better than before, where all that stuff was available in plaintext
    - milkey_mouse 5y ago
      Signal didn't back up contacts and settings to their servers until they implemented "Secure Value Recovery", which relies on SGX to rate-limit guesses of a weak PIN. If SGX is broken and Signal's database falls into the wrong hands, encryption keys could be brute-forced pretty quickly (most people have 4-digit PINs).

mindslight 5y ago

It's a societal dead end, so there's no technical excitement. The same technology that would let you verify a cloud server is running code you specify, would also be used by websites to demand that your personal computing environment conforms to their whims. Imagine websites that required proprietary Google Chrome on Win/OSX on bare metal - no VM, no extensions, no third party clients, no automation, etc. Imagine mandatory ads, unsaveable images, client-side form verification, completely unaccountable code, etc. Protocols are the proper manner of allowing unrelated parties to transact at arm's length, and technologies such as remote attestation would completely destroy that.

KirillPanov 5y ago
> Imagine websites that required proprietary Google Chrome on Win/OSX on bare metal - no VM, no extensions, no third party clients, no automation, etc. No need to imagine, we already have that: it's called fingerprinting. Mainly via WebGL.
- mindslight 5y ago
  There is a major difference between something being difficult/annoying, and outright impossible.

tyingq 5y ago

Memory tagging looks interesting to me. This paper from LowRISC outlines the possibilities pretty well: https://riscv.org/wp-content/uploads/2017/05/Wed0930riscv201705_ppt.pdf https://riscv.org/wp-content/uploads/2017/05/Wed0930riscv201... Referencing that not to plug RiscV, but solely because it's a good explanation. I would guess Intel, AMD, and ARM have plans or some existing work going on.

pjmlp 5y ago
Memory tagging is already been used successfully for years on Solaris SPARC, https://docs.oracle.com/cd/E37838_01/html/E61059/gqajs.html https://docs.oracle.com/cd/E37838_01/html/E61059/gqajs.html In what concerns ARM, all Android 11 and later versions are going to support it. https://security.googleblog.com/2019/08/adopting-arm-memory-tagging-extension.html https://security.googleblog.com/2019/08/adopting-arm-memory-... https://source.android.com/devices/tech/debug/tagged-pointers https://source.android.com/devices/tech/debug/tagged-pointer... Unfortunelly Intel's MPX was a failure, for reasons, however the rest of the CPU vendors seems to be going into the C machine model, as only way left to fix the language.

Ar-Curunir 5y ago

Verifiable OSS doesn’t stop a malicious operator from just looking at your bits in memory