tor/changes/bug10402

  o Major bugfixes:
    - Do not allow OpenSSL engines to replace the PRNG, even when
      HardwareAccel is set. The only default builtin PRNG engine uses
      the Intel RDRAND instruction to replace the entire PRNG, and
      ignores all attempts to seed it with more entropy. That's
      cryptographically stupid: the right response to a new alleged
      entropy source is never to discard all previously used entropy
      sources. Fixes bug 10402; works around behavior introduced in
      OpenSSL 1.0.0. Diagnosis and investigation thanks to "coderman"
      and "rl1987".
Never allow OpenSSL engines to replace the RAND_SSLeay method This fixes bug 10402, where the rdrand engine would use the rdrand instruction, not as an additional entropy source, but as a replacement for the entire userspace PRNG. That's obviously stupid: even if you don't think that RDRAND is a likely security risk, the right response to an alleged new alleged entropy source is never to throw away all previously used entropy sources. Thanks to coderman and rl1987 for diagnosing and tracking this down. 2013-12-18 17:49:44 +01:00			`o Major bugfixes:`
			`- Do not allow OpenSSL engines to replace the PRNG, even when`
			`HardwareAccel is set. The only default builtin PRNG engine uses`
			`the Intel RDRAND instruction to replace the entire PRNG, and`
			`ignores all attempts to seed it with more entropy. That's`
			`cryptographically stupid: the right response to a new alleged`
			`entropy source is never to discard all previously used entropy`
			`sources. Fixes bug 10402; works around behavior introduced in`
			`OpenSSL 1.0.0. Diagnosis and investigation thanks to "coderman"`
			`and "rl1987".`