GlcoinCore/elements
1
0
Fork 0
mirror of https://github.com/ElementsProject/elements.git synced 2026-08-20 13:37:28 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 1

Merge 947f2925d5 into merged_master (Bitcoin PR bitcoin/bitcoin#31124)

Browse source
This commit is contained in:
Tom Trevethan 2026-03-31 23:16:05 +01:00
commit 4719eae2c6
3 changed files with 3 additions and 45 deletions
Download patch file Download diff file Expand all files Collapse all files

4
src/random.cpp
View file

@ -599,7 +599,7 @@ void SeedPeriodic(CSHA512& hasher, RNGState& rng) noexcept
// Add the events hasher into the mix
rng.SeedEvents(hasher);
// Dynamic environment data (performance monitoring, ...)
// Dynamic environment data (clocks, resource usage, ...)
auto old_size = hasher.Size();
RandAddDynamicEnv(hasher);
LogDebug(BCLog::RAND, "Feeding %i bytes of dynamic environment data into RNG\n", hasher.Size() - old_size);
@ -616,7 +616,7 @@ void SeedStartup(CSHA512& hasher, RNGState& rng) noexcept
// Everything that the 'slow' seeder includes.
SeedSlow(hasher, rng);
// Dynamic environment data (performance monitoring, ...)
// Dynamic environment data (clocks, resource usage, ...)
auto old_size = hasher.Size();
RandAddDynamicEnv(hasher);

2
src/random.h
View file

@ -49,7 +49,7 @@
*
* - RandAddPeriodic() seeds everything that fast seeding includes, but additionally:
* - A high-precision timestamp
* - Dynamic environment data (performance monitoring, ...)
* - Dynamic environment data (clocks, resource usage, ...)
* - Strengthen the entropy for 10 ms using repeated SHA512.
* This is run once every minute.
*

42
src/randomenv.cpp
View file

@ -28,7 +28,6 @@
#ifdef WIN32
#include <windows.h>
#include <winreg.h>
#else
#include <fcntl.h>
#include <netinet/in.h>
@ -64,45 +63,6 @@ extern char** environ; // NOLINT(readability-redundant-declaration): Necessary o
namespace {
void RandAddSeedPerfmon(CSHA512& hasher)
{
#ifdef WIN32
// Seed with the entire set of perfmon data
// This can take up to 2 seconds, so only do it every 10 minutes.
// Initialize last_perfmon to 0 seconds, we don't skip the first call.
static std::atomic<SteadyClock::time_point> last_perfmon{SteadyClock::time_point{0s}};
auto last_time = last_perfmon.load();
auto current_time = SteadyClock::now();
if (current_time < last_time + 10min) return;
last_perfmon = current_time;
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::min((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
}
/** Helper to easily feed data into a CSHA512.
*
* Note that this does not serialize the passed object (like stream.h's << operators do).
@ -227,8 +187,6 @@ void AddAllCPUID(CSHA512& hasher)
void RandAddDynamicEnv(CSHA512& hasher)
{
RandAddSeedPerfmon(hasher);
// Various clocks
#ifdef WIN32
FILETIME ftime;