[tor-bugs] #14788 [Tor]: Use unpredictability better on Windows

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#14788: Use unpredictability better on Windows
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 Reporter:  anon         |          Owner:
     Type:  enhancement  |         Status:  new
 Priority:  normal       |      Milestone:
Component:  Tor          |        Version:
 Keywords:               |  Actual Points:
Parent ID:               |         Points:
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 Use unpredictability better on Windows

 On Win32 / Win64 and using either CryptGenRandom or RtlGenRandom read and
 drop first 128Kbytes of *GenRandom before
  calling again for entropy to be used for key material or deterministic
 generators.

 This is due to possibly insecure/exposed PRNG state on some win32 hosts
 this read past the first 128Kbytes of generator output before is explained
 in http://eprint.iacr.org/2007/419

 See:
  gitweb.torproject.org/tor.git/tree/src/common/crypto.c#n2457
 crypto_strongest_rand();

 Also,
  <skruffy> https://privatepaste.com/45ff1fac9f here another idea used
 mingw specific of crt, simple and no any extra linking.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/14788>
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