[MOVEONLY] Move perfmon data gathering to new randomenv module

Author: sipa

src/Makefile.am

@@ -175,6 +175,7 @@ BITCOIN_CORE_H = \
   protocol.h \
   psbt.h \
   random.h \
+  randomenv.h \
   reverse_iterator.h \
   reverselock.h \
   rpc/blockchain.h \
@@ -502,6 +503,7 @@ libbitcoin_util_a_SOURCES = \
   interfaces/handler.cpp \
   logging.cpp \
   random.cpp \
+  randomenv.cpp \
   rpc/request.cpp \
   support/cleanse.cpp \
   sync.cpp \

src/random.cpp

@@ -18,6 +18,8 @@
 #include <stdlib.h>
 #include <thread>
 
+#include <randomenv.h>
+
 #include <support/allocators/secure.h>
 
 #ifndef WIN32
@@ -263,44 +265,6 @@ static void Strengthen(const unsigned char (&seed)[32], int microseconds, CSHA51
     memory_cleanse(buffer, sizeof(buffer));
 }
 
-static void RandAddSeedPerfmon(CSHA512& hasher)
-{
-#ifdef WIN32
-    // Don't need this on Linux, OpenSSL automatically uses /dev/urandom
-    // Seed with the entire set of perfmon data
-
-    // This can take up to 2 seconds, so only do it every 10 minutes
-    static int64_t nLastPerfmon;
-    if (GetTime() < nLastPerfmon + 10 * 60)
-        return;
-    nLastPerfmon = GetTime();
-
-    std::vector<unsigned char> vData(250000, 0);
-    long ret = 0;
-    unsigned long nSize = 0;
-    const size_t nMaxSize = 10000000; // Bail out at more than 10MB of performance data
-    while (true) {
-        nSize = vData.size();
-        ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", nullptr, nullptr, vData.data(), &nSize);
-        if (ret != ERROR_MORE_DATA || vData.size() >= nMaxSize)
-            break;
-        vData.resize(std::max((vData.size() * 3) / 2, nMaxSize)); // Grow size of buffer exponentially
-    }
-    RegCloseKey(HKEY_PERFORMANCE_DATA);
-    if (ret == ERROR_SUCCESS) {
-        hasher.Write(vData.data(), nSize);
-        memory_cleanse(vData.data(), nSize);
-    } else {
-        // Performance data is only a best-effort attempt at improving the
-        // situation when the OS randomness (and other sources) aren't
-        // adequate. As a result, failure to read it is isn't considered critical,
-        // so we don't call RandFailure().
-        // TODO: Add logging when the logger is made functional before global
-        // constructors have been invoked.
-    }
-#endif
-}
-
 #ifndef WIN32
 /** Fallback: get 32 bytes of system entropy from /dev/urandom. The most
  * compatible way to get cryptographic randomness on UNIX-ish platforms.
@@ -585,8 +549,8 @@ static void SeedSleep(CSHA512& hasher, RNGState& rng)
     // High-precision timestamp after sleeping (as we commit to both the time before and after, this measures the delay)
     SeedTimestamp(hasher);
 
-    // Windows performance monitor data (once every 10 minutes)
-    RandAddSeedPerfmon(hasher);
+    // Dynamic environment data (performance monitoring, ...; once every 10 minutes)
+    RandAddDynamicEnv(hasher);
 
     // Strengthen every minute
     SeedStrengthen(hasher, rng);
@@ -600,8 +564,11 @@ static void SeedStartup(CSHA512& hasher, RNGState& rng) noexcept
     // Everything that the 'slow' seeder includes.
     SeedSlow(hasher);
 
-    // Windows performance monitor data.
-    RandAddSeedPerfmon(hasher);
+    // Dynamic environment data
+    RandAddDynamicEnv(hasher);
+
+    // Static environment data
+    RandAddStaticEnv(hasher);
 
     // Strengthen
     SeedStrengthen(hasher, rng);

src/randomenv.cpp

@@ -0,0 +1,69 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include <randomenv.h>
+
+#include <crypto/sha512.h>
+#include <support/cleanse.h>
+#include <util/time.h> // for GetTime()
+#ifdef WIN32
+#include <compat.h> // for Windows API
+#endif
+
+#include <algorithm>
+#include <vector>
+
+#include <stdint.h>
+
+namespace {
+
+void RandAddSeedPerfmon(CSHA512& hasher)
+{
+#ifdef WIN32
+    // Don't need this on Linux, OpenSSL automatically uses /dev/urandom
+    // Seed with the entire set of perfmon data
+
+    // This can take up to 2 seconds, so only do it every 10 minutes
+    static int64_t nLastPerfmon;
+    if (GetTime() < nLastPerfmon + 10 * 60)
+        return;
+    nLastPerfmon = GetTime();
+
+    std::vector<unsigned char> vData(250000, 0);
+    long ret = 0;
+    unsigned long nSize = 0;
+    const size_t nMaxSize = 10000000; // Bail out at more than 10MB of performance data
+    while (true) {
+        nSize = vData.size();
+        ret = RegQueryValueExA(HKEY_PERFORMANCE_DATA, "Global", nullptr, nullptr, vData.data(), &nSize);
+        if (ret != ERROR_MORE_DATA || vData.size() >= nMaxSize)
+            break;
+        vData.resize(std::max((vData.size() * 3) / 2, nMaxSize)); // Grow size of buffer exponentially
+    }
+    RegCloseKey(HKEY_PERFORMANCE_DATA);
+    if (ret == ERROR_SUCCESS) {
+        hasher.Write(vData.data(), nSize);
+        memory_cleanse(vData.data(), nSize);
+    } else {
+        // Performance data is only a best-effort attempt at improving the
+        // situation when the OS randomness (and other sources) aren't
+        // adequate. As a result, failure to read it is isn't considered critical,
+        // so we don't call RandFailure().
+        // TODO: Add logging when the logger is made functional before global
+        // constructors have been invoked.
+    }
+#endif
+}
+
+} // namespace
+
+void RandAddDynamicEnv(CSHA512& hasher)
+{
+    RandAddSeedPerfmon(hasher);
+}
+
+void RandAddStaticEnv(CSHA512& hasher)
+{
+}

src/randomenv.h

@@ -0,0 +1,17 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2019 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_RANDOMENV_H
+#define BITCOIN_RANDOMENV_H
+
+#include <crypto/sha512.h>
+
+/** Gather non-cryptographic environment data that changes over time. */
+void RandAddDynamicEnv(CSHA512& hasher);
+
+/** Gather non-cryptographic environment data that does not change over time. */
+void RandAddStaticEnv(CSHA512& hasher);
+
+#endif