mirror of
https://github.com/klzgrad/naiveproxy.git
synced 2024-11-28 16:26:10 +03:00
95 lines
2.6 KiB
C++
95 lines
2.6 KiB
C++
// Copyright 2012 The Chromium Authors
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
#include "base/rand_util.h"
|
|
|
|
#include <windows.h>
|
|
#include <stddef.h>
|
|
#include <stdint.h>
|
|
|
|
// #define needed to link in RtlGenRandom(), a.k.a. SystemFunction036. See the
|
|
// "Community Additions" comment on MSDN here:
|
|
// http://msdn.microsoft.com/en-us/library/windows/desktop/aa387694.aspx
|
|
#define SystemFunction036 NTAPI SystemFunction036
|
|
#include <NTSecAPI.h>
|
|
#undef SystemFunction036
|
|
|
|
#include <algorithm>
|
|
#include <atomic>
|
|
#include <limits>
|
|
|
|
#include "base/check.h"
|
|
#include "base/feature_list.h"
|
|
#include "third_party/boringssl/src/include/openssl/crypto.h"
|
|
#include "third_party/boringssl/src/include/openssl/rand.h"
|
|
|
|
namespace base {
|
|
|
|
namespace internal {
|
|
|
|
namespace {
|
|
|
|
// The BoringSSl helpers are duplicated in rand_util_fuchsia.cc and
|
|
// rand_util_posix.cc.
|
|
std::atomic<bool> g_use_boringssl;
|
|
|
|
BASE_FEATURE(kUseBoringSSLForRandBytes,
|
|
"UseBoringSSLForRandBytes",
|
|
FEATURE_DISABLED_BY_DEFAULT);
|
|
|
|
} // namespace
|
|
|
|
void ConfigureBoringSSLBackedRandBytesFieldTrial() {
|
|
g_use_boringssl.store(FeatureList::IsEnabled(kUseBoringSSLForRandBytes),
|
|
std::memory_order_relaxed);
|
|
}
|
|
|
|
bool UseBoringSSLForRandBytes() {
|
|
return g_use_boringssl.load(std::memory_order_relaxed);
|
|
}
|
|
|
|
} // namespace internal
|
|
|
|
namespace {
|
|
|
|
void RandBytes(void* output, size_t output_length, bool avoid_allocation) {
|
|
if (!avoid_allocation && internal::UseBoringSSLForRandBytes()) {
|
|
// Ensure BoringSSL is initialized so it can use things like RDRAND.
|
|
CRYPTO_library_init();
|
|
// BoringSSL's RAND_bytes always returns 1. Any error aborts the program.
|
|
(void)RAND_bytes(static_cast<uint8_t*>(output), output_length);
|
|
return;
|
|
}
|
|
|
|
char* output_ptr = static_cast<char*>(output);
|
|
while (output_length > 0) {
|
|
const ULONG output_bytes_this_pass = static_cast<ULONG>(std::min(
|
|
output_length, static_cast<size_t>(std::numeric_limits<ULONG>::max())));
|
|
const bool success =
|
|
RtlGenRandom(output_ptr, output_bytes_this_pass) != FALSE;
|
|
CHECK(success);
|
|
output_length -= output_bytes_this_pass;
|
|
output_ptr += output_bytes_this_pass;
|
|
}
|
|
}
|
|
|
|
} // namespace
|
|
|
|
void RandBytes(void* output, size_t output_length) {
|
|
RandBytes(output, output_length, /*avoid_allocation=*/false);
|
|
}
|
|
|
|
namespace internal {
|
|
|
|
double RandDoubleAvoidAllocation() {
|
|
uint64_t number;
|
|
RandBytes(&number, sizeof(number), /*avoid_allocation=*/true);
|
|
// This transformation is explained in rand_util.cc.
|
|
return (number >> 11) * 0x1.0p-53;
|
|
}
|
|
|
|
} // namespace internal
|
|
|
|
} // namespace base
|