Merge #14955: Switch all RNG code to the built-in PRNG

223de8d94d6522f795ec3c2e7db27469f24aa68c Document RNG design in random.h (Pieter Wuille)
f2e60ca98530e0a865ff6c6fd3c5633aec11a515 Use secure allocator for RNG state (Pieter Wuille)
cddb31bb0a132afa50b5350196cf26f0064fe3e2 Encapsulate RNGState better (Pieter Wuille)
152146e782d401aa1ce7d989d62306aabc85f22e DRY: Implement GetRand using FastRandomContext::randrange (Pieter Wuille)
a1f252eda87356fa329c838a7bf569808489648f Sprinkle some sweet noexcepts over the RNG code (Pieter Wuille)
4ea8e50837a0932b31a241988fd68d6730a2048a Remove hwrand_initialized. (Pieter Wuille)
9d7032e4f066777c97c58b1394884716e213790a Switch all RNG code to the built-in PRNG. (Pieter Wuille)
16e40a8b562ad849a5f5e8b21ceb375e46038243 Integrate util/system's CInit into RNGState (Pieter Wuille)
2ccc3d3aa346e96206281a391bc29874cf5ee7f4 Abstract out seeding/extracting entropy into RNGState::MixExtract (Pieter Wuille)
aae8b9bf0f4fd2b801ee72cf191588c8b3a67c3c Add thread safety annotations to RNG state (Pieter Wuille)
d3f54d1c82b131d817b20cd9daa75f9d3c9475e1 Rename some hardware RNG related functions (Pieter Wuille)
05fde14e3afe6f7156ebb6df6cd0e3ae12635b89 Automatically initialize RNG on first use. (Pieter Wuille)
2d1cc5093949f8ea9487a68724162c8b39035ad8 Don't log RandAddSeedPerfmon details (Pieter Wuille)
6a57ca91da23c6a5d91399ffc7fc09a99b6d4c76 Use FRC::randbytes instead of reading >32 bytes from RNG (Pieter Wuille)

Pull request description:

  This does not remove OpenSSL, but makes our own PRNG the 'main' one; for GetStrongRandBytes, the OpenSSL RNG is still used (indirectly, by feeding its output into our PRNG state).

  It includes a few policy changes (regarding what entropy is seeded when).

  Before this PR:
  * GetRand*:
    * OpenSSL
  * GetStrongRand*:
    * CPU cycle counter
    * Perfmon data (on Windows, once 10 min)
    * /dev/urandom (or equivalent)
    * rdrand (if available)
  * From scheduler when idle:
    * CPU cycle counter before and after 1ms sleep
  * At startup:
    * CPU cycle counter before and after 1ms sleep

  After this PR:
  * GetRand*:
    * Stack pointer (which indirectly identifies thread and some call stack information)
    * rdrand (if available)
    * CPU cycle counter
  * GetStrongRand*:
    * Stack pointer (which indirectly identifies thread and some call stack information)
    * rdrand (if available)
    * CPU cycle counter
    * /dev/urandom (or equivalent)
    * OpenSSL
    * CPU cycle counter again
  * From scheduler when idle:
    * Stack pointer (which indirectly identifies thread and some call stack information)
    * rdrand (if available)
    * CPU cycle counter before and after 1ms sleep
    * Perfmon data (on Windows, once every 10 min)
  * At startup:
    * Stack pointer (which indirectly identifies thread and some call stack information)
    * rdrand (if available)
    * CPU cycle counter
    * /dev/urandom (or equivalent)
    * OpenSSL
    * CPU cycle counter again
    * Perfmon data (on Windows, once every 10 min)

  The interface of random.h is also simplified, and documentation is added.

  This implements most of #14623.

Tree-SHA512: 0120e19bd4ce80a509b5c180a4f29497d299ce8242e25755880851344b825bc2d64a222bc245e659562fb5463fb7c70fbfcf003616be4dc59d0ed6534f93dd20

1 files changed, 0 insertions, 51 deletions

diff --git a/src/util/system.cpp b/src/util/system.cpp
index 3ef8111b32..06317a3a90 100644
--- a/src/util/system.cpp
+++ b/src/util/system.cpp
@@ -73,9 +73,6 @@
 #include <malloc.h>
 #endif
 
-#include <openssl/crypto.h>
-#include <openssl/rand.h>
-#include <openssl/conf.h>
 #include <thread>
 
 // Application startup time (used for uptime calculation)
@@ -86,54 +83,6 @@ const char * const BITCOIN_PID_FILENAME = "bitcoind.pid";
 
 ArgsManager gArgs;
 
-/** Init OpenSSL library multithreading support */
-static std::unique_ptr<CCriticalSection[]> ppmutexOpenSSL;
-void locking_callback(int mode, int i, const char* file, int line) NO_THREAD_SAFETY_ANALYSIS
-{
-    if (mode & CRYPTO_LOCK) {
-        ENTER_CRITICAL_SECTION(ppmutexOpenSSL[i]);
-    } else {
-        LEAVE_CRITICAL_SECTION(ppmutexOpenSSL[i]);
-    }
-}
-
-// Singleton for wrapping OpenSSL setup/teardown.
-class CInit
-{
-public:
-    CInit()
-    {
-        // Init OpenSSL library multithreading support
-        ppmutexOpenSSL.reset(new CCriticalSection[CRYPTO_num_locks()]);
-        CRYPTO_set_locking_callback(locking_callback);
-
-        // OpenSSL can optionally load a config file which lists optional loadable modules and engines.
-        // We don't use them so we don't require the config. However some of our libs may call functions
-        // which attempt to load the config file, possibly resulting in an exit() or crash if it is missing
-        // or corrupt. Explicitly tell OpenSSL not to try to load the file. The result for our libs will be
-        // that the config appears to have been loaded and there are no modules/engines available.
-        OPENSSL_no_config();
-
-#ifdef WIN32
-        // Seed OpenSSL PRNG with current contents of the screen
-        RAND_screen();
-#endif
-
-        // Seed OpenSSL PRNG with performance counter
-        RandAddSeed();
-    }
-    ~CInit()
-    {
-        // Securely erase the memory used by the PRNG
-        RAND_cleanup();
-        // Shutdown OpenSSL library multithreading support
-        CRYPTO_set_locking_callback(nullptr);
-        // Clear the set of locks now to maintain symmetry with the constructor.
-        ppmutexOpenSSL.reset();
-    }
-}
-instance_of_cinit;
-
 /** A map that contains all the currently held directory locks. After
  * successful locking, these will be held here until the global destructor
  * cleans them up and thus automatically unlocks them, or ReleaseDirectoryLocks