Index: base/rand_util_win.cc |
diff --git a/base/rand_util_win.cc b/base/rand_util_win.cc |
index 35f2d2e863ab83f84e0c00dffe19872f808fa43a..3047a7ac904c887798f17a5bfd2ca557482c59c5 100644 |
--- a/base/rand_util_win.cc |
+++ b/base/rand_util_win.cc |
@@ -4,18 +4,34 @@ |
#include "base/rand_util.h" |
+#include <limits.h> |
wtc
2014/01/22 22:42:04
I don't think you are using anything from the C he
|
+#include <stdint.h> |
#include <stdlib.h> |
+#include <windows.h> |
-#include "base/basictypes.h" |
+#include "base/lazy_instance.h" |
#include "base/logging.h" |
namespace { |
wtc
2014/01/22 22:42:04
Nit: add a blank line after this line.
|
+typedef BOOLEAN (WINAPI *RtlGenRandomPtr)(PVOID, ULONG); |
+ |
+class WinRandom { |
+ public: |
+ WinRandom() |
+ : rtl_gen_random_(reinterpret_cast<RtlGenRandomPtr>( |
+ ::GetProcAddress(::GetModuleHandle(L"advapi32.dll"), |
+ "SystemFunction036"))) {} |
+ ~WinRandom() {} |
+ |
+ void RtlGenRandom(void* output, uint32_t output_length) const { |
+ CHECK_EQ(rtl_gen_random_(output, output_length), TRUE); |
+ } |
-uint32 RandUint32() { |
- uint32 number; |
- CHECK_EQ(rand_s(&number), 0); |
- return number; |
-} |
+ private: |
+ const RtlGenRandomPtr rtl_gen_random_; |
+}; |
+ |
+base::LazyInstance<WinRandom>::Leaky g_win_random = LAZY_INSTANCE_INITIALIZER; |
} // namespace |
@@ -23,18 +39,20 @@ namespace base { |
// NOTE: This function must be cryptographically secure. http://crbug.com/140076 |
uint64 RandUint64() { |
- uint32 first_half = RandUint32(); |
- uint32 second_half = RandUint32(); |
- return (static_cast<uint64>(first_half) << 32) + second_half; |
+ uint64 number; |
+ g_win_random.Pointer()->RtlGenRandom(&number, sizeof(number)); |
+ return number; |
} |
void RandBytes(void* output, size_t output_length) { |
- uint64 random_int; |
- const size_t random_int_size = sizeof(random_int); |
- for (size_t i = 0; i < output_length; i += random_int_size) { |
- random_int = base::RandUint64(); |
- size_t copy_count = std::min(output_length - i, random_int_size); |
- memcpy(((uint8*)output) + i, &random_int, copy_count); |
+ char* output_ptr = static_cast<char*>(output); |
+ const WinRandom* win_random_ptr = g_win_random.Pointer(); |
wtc
2014/01/22 22:42:04
Nit: this should be
const WinRandom* const win_r
|
+ while (output_length > 0) { |
+ const uint32_t output_bytes_this_pass = static_cast<uint32_t>( |
+ std::min(output_length, std::numeric_limits<uint32_t>::max())); |
+ win_random_ptr->RtlGenRandom(output_ptr, output_bytes_this_pass); |
+ output_length -= output_bytes_this_pass; |
+ output_ptr += output_bytes_this_pass; |
} |
} |