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A comment on Random Number Generator Recommendations for Applications. Parent comment

Re:Random Number Generator Recommendations for Applications by jameswryan on Tuesday May 30, 2023 @10:46PM (#36133912)
/dev/random does not block when 'out of entropy'. 'Running out of entropy' isn't something that can happen, and /dev/random will only block if the RNG hasn't been initialized (short enough after boot to not matter).

See Jason Donenfeld's authoritative talk on the Linux RNG for details: https://youtu.be/-_yzaSp2xtY

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Re:Random Number Generator Recommendations for Applications by cbsmith on Wednesday May 31, 2023 @11:59AM (#36139870)
I'll have to look at the talk, but I've had first hand experience with that behaviour from /dev/random. Perhaps it has changed over time.
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Re:Random Number Generator Recommendations for Applications by cbsmith on Wednesday May 31, 2023 @01:16PM (#36140873)
I just checked the source code, and it appears that the entropy pool is alive and well and that /dev/random still waits for enough entropy to collect in the pool before providing more data for consumption.

https://github.com/torvalds/linux/blob/48b1320a674e1ff5de2fa...

The "wait_for_random_bytes" function is still there: https://github.com/torvalds/linux/blob/48b1320a674e1ff5de2fa...

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