blob: 5f991d5cc053db910b02ccc268345db677bb775f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
|
// Copyright 2017 The Chromium Authors. All rights reserved.
// 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 <zircon/syscalls.h>
#include <algorithm>
#include "base/logging.h"
namespace base {
void RandBytes(void* output, size_t output_length) {
size_t remaining = output_length;
unsigned char* cur = reinterpret_cast<unsigned char*>(output);
while (remaining > 0) {
// The syscall has a maximum number of bytes that can be read at once.
size_t read_len =
std::min(remaining, static_cast<size_t>(ZX_CPRNG_DRAW_MAX_LEN));
size_t actual;
zx_status_t status = zx_cprng_draw(cur, read_len, &actual);
CHECK(status == ZX_OK && read_len == actual);
CHECK(remaining >= actual);
remaining -= actual;
cur += actual;
}
}
} // namespace base
|
