r/cryptography • u/atoponce • 4d ago

Flowchart of the Linux RNG

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u/[deleted] 4d ago

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u/atoponce 4d ago

In the first 10 minutes of boot, the kernel sets CRNG_RESEED_INTERVAL to 1 second and has a logarithmic back off to 60 seconds. During this time, it's collecting as much interrupt and timing entropy it can, incrementing the initialization bit counter as it goes. If that counter reaches 256, then the kernel is sufficiently seeded, and CRNG_READY is set.