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Here's a thread on how bitcoin core generates entropy https://twitter.com/raw_avocado/status/1445024873382809604 https://twitter.com/raw_avocado/status/14450248

Here's a thread on how bitcoin core generates entropy https://twitter.com/raw_avocado/status/1445024873382809604 https://twitter.com/raw_avocado/status/1445024873382809604

nullc 3y ago
that thread is a little confused: Particularly, 'The Dynamic and Static events are mixed in(mostly) by using "<<" Left Shift Bits. Because it's a binary operation, every digit is a power of 2, so shifting the bit n positions ends up multiplying by 2^n. This adds further confusion when multiple numbers are used at once.' --- the tweet appears to be confusing C++ stream usage of "<<" with shifting (and as a result makes it sound like the code is doing something idiotic). Here is how it works: Lots of potential entropy sources including the essential good ones (as well as junk ones like timestamps and user/host info) are fed into a cryptographic hash then strengthened with iterated hashing. The junk sources are included as a hail mary so the user might have some chance to move their funds if they learn about vulnerabilities in their OS/hardware RNGs before an attacker can brute force out the weak sources.
- alexwaltz 3y ago
  OMG, i'm a bit star struck seeing you reply to this. Been reading you posts on btctalk for years :D Sorry about that, my bad, I though i understand how that works, when I was exploring this topic i literally asked everyone i know and no one seemed to have any idea, and then when i felt i got a conclusion i was happy i found some explanation. Anyway that just an excuse at the end of the day. I have added to the thread a screenshoot of your reply and link to this conversation. https://twitter.com/raw_avocado/status/1689317198626422784 https://twitter.com/raw_avocado/status/1689317198626422784 Thanks for clarifying that.
  - nullc 3y ago
    No need for excuses. The fact that people didn't already get this stuff well enough to correct you on the spot suggests that there is a need for more explanation!

Here's a thread on how bitcoin core generates entropy https://twitter.com/raw_avocado/status/1445024873382809604 https://twitter.com/raw_avocado/status/1445024873382809604

nullc 3y ago

that thread is a little confused: Particularly, 'The Dynamic and Static events are mixed in(mostly) by using "<<" Left Shift Bits. Because it's a binary operation, every digit is a power of 2, so shifting the bit n positions ends up multiplying by 2^n. This adds further confusion when multiple numbers are used at once.' --- the tweet appears to be confusing C++ stream usage of "<<" with shifting (and as a result makes it sound like the code is doing something idiotic). Here is how it works: Lots of potential entropy sources including the essential good ones (as well as junk ones like timestamps and user/host info) are fed into a cryptographic hash then strengthened with iterated hashing. The junk sources are included as a hail mary so the user might have some chance to move their funds if they learn about vulnerabilities in their OS/hardware RNGs before an attacker can brute force out the weak sources.

alexwaltz 3y ago
OMG, i'm a bit star struck seeing you reply to this. Been reading you posts on btctalk for years :D Sorry about that, my bad, I though i understand how that works, when I was exploring this topic i literally asked everyone i know and no one seemed to have any idea, and then when i felt i got a conclusion i was happy i found some explanation. Anyway that just an excuse at the end of the day. I have added to the thread a screenshoot of your reply and link to this conversation. https://twitter.com/raw_avocado/status/1689317198626422784 https://twitter.com/raw_avocado/status/1689317198626422784 Thanks for clarifying that.
- nullc 3y ago
  No need for excuses. The fact that people didn't already get this stuff well enough to correct you on the spot suggests that there is a need for more explanation!