1 /*
2 * Copyright (c) 2021-2022 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include "random_mbedtls.h"
17 #include "access_token.h"
18
19 using OHOS::Security::AccessToken::RandomMbedtls;
20 using OHOS::Security::AccessToken::RET_SUCCESS;
21
22 namespace OHOS {
23 namespace Security {
24 namespace AccessToken {
GetRandomUint32()25 extern "C" unsigned int GetRandomUint32()
26 {
27 unsigned int rand;
28 int ret = RandomMbedtls::GetInstance().GenerateRandomArray((unsigned char *)&rand, sizeof(rand));
29 if (ret != RET_SUCCESS) {
30 return 0;
31 }
32 return rand;
33 }
34
GenerateRandomArray(unsigned char * randStr,unsigned int len)35 int RandomMbedtls::GenerateRandomArray(unsigned char *randStr, unsigned int len)
36 {
37 if (randStr == nullptr || len == 0) {
38 return RET_FAILED;
39 }
40 int ret;
41
42 Utils::UniqueWriteGuard<Utils::RWLock> infoGuard(this->randomLock_);
43 if (!initFlag_) {
44 mbedtls_ctr_drbg_init(&ctrDrbg_);
45 mbedtls_entropy_init(&entropy_);
46 ret = mbedtls_ctr_drbg_seed(&ctrDrbg_, mbedtls_entropy_func, &entropy_, nullptr, 0);
47 if (ret != 0) {
48 return RET_FAILED;
49 }
50 initFlag_ = true;
51 }
52
53 ret = mbedtls_ctr_drbg_random(&ctrDrbg_, randStr, len);
54 if (ret != 0) {
55 return RET_FAILED;
56 }
57 return RET_SUCCESS;
58 }
59
GetInstance()60 RandomMbedtls& RandomMbedtls::GetInstance()
61 {
62 static RandomMbedtls instance;
63 return instance;
64 }
65 } // namespace AccessToken
66 } // namespace Security
67 } // namespace OHOS
68