Switch all RNG code to the built-in PRNG.

It includes the following policy changes:
* All GetRand* functions seed the stack pointer and rdrand result
  (in addition to the performance counter)
* The periodic entropy added by the idle scheduler now seeds stack pointer,
  rdrand and perfmon data (once every 10 minutes) in addition to
  just a sleep timing.
* The entropy added when calling GetStrongRandBytes no longer includes
  the once-per-10-minutes perfmon data on windows (it is moved to the
  idle scheduler instead, where latency matters less).

Other changes:
* OpenSSL is no longer seeded directly anywhere. Instead, any generated
  randomness through our own RNG is fed back to OpenSSL (after an
  additional hashing step to prevent leaking our RNG state).
* Seeding that was previously done directly in RandAddSeedSleep is now
  moved to SeedSleep(), which is indirectly invoked through ProcRand
  from RandAddSeedSleep.
* Seeding that was previously done directly in GetStrongRandBytes()
  is now moved to SeedSlow(), which is indirectly invoked through
  ProcRand from GetStrongRandBytes().

1 files changed, 1 insertions, 1 deletions

diff --git a/src/scheduler.cpp b/src/scheduler.cpp
index b2da62fc75..fdc859b3a0 100644
--- a/src/scheduler.cpp
+++ b/src/scheduler.cpp
@@ -41,7 +41,7 @@ void CScheduler::serviceQueue()
         try {
             if (!shouldStop() && taskQueue.empty()) {
                 reverse_lock<boost::unique_lock<boost::mutex> > rlock(lock);
-                // Use this chance to get a tiny bit more entropy
+                // Use this chance to get more entropy
                 RandAddSeedSleep();
             }
             while (!shouldStop() && taskQueue.empty()) {