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Many computers have TPMs or Secure Enclaves or whatnot these days. Many CPUs have similar or subset functionality built in. Why don’t manufacturers start to a
by efitz 5y ago
Many computers have TPMs or Secure Enclaves or whatnot these days. Many CPUs have similar or subset functionality built in. Why don’t manufacturers start to add hardware entropy sources? Then /dev/*random could source entropy from a driver, not an algorithm.
Yes, I know that it only fixes things going forward, and I know that the answer to any question that starts with “why don’t they” is “money”.
Sigh.
- CorrectHorseBat 5y agoBut they do: https://en.m.wikipedia.org/wiki/RDRAND https://en.m.wikipedia.org/wiki/RDRAND
- zx2c4 5y agoCONFIG_RANDOM_TRUST_CPU=y CONFIG_RANDOM_TRUST_BOOTLOADER=y CONFIG_HW_RANDOM=y CONFIG_HW_RANDOM_TPM=y and so forth all exist.
- josefx 5y ago> “why don’t they” is “money”. More likely "trust". A purpose build instruction with a black box implementation on hardware that has its own hidden OS with direct access to the network is one issue. The fact that Intels CPUs are a bug riddled mess that have been a significant headache to anyone caring about kernel and application layer security is another. Who needs security if disabling all the mitigations makes you look great on benchmarks.
- efitz 5y agoA HES or a HRNG is observable and testable. And we trust purpose built security hardware all the time; think crypto accelerator cards and HSMs.
- CorrectHorseBat 5y agoIt's much harder to test the output of a TRNG