1 /*
2 * Copyright (c) 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 "dm_random.h"
17
18 #include <random>
19
20 #include "mbedtls/ctr_drbg.h"
21 #include "mbedtls/entropy.h"
22
23 #if defined(__LITEOS_M__)
24 #include <time.h>
25 #endif
26
27 namespace OHOS {
28 namespace DistributedHardware {
29 constexpr uint32_t ERR_DM_FAILED = -20000;
30 constexpr int32_t DM_OK = 0;
GenRandInt(int32_t randMin,int32_t randMax)31 int32_t GenRandInt(int32_t randMin, int32_t randMax)
32 {
33 #if defined(__LITEOS_M__)
34 srandom(time(NULL));
35 return (randMin + random() % (randMax - randMin));
36 #else
37 std::random_device randDevice;
38 std::mt19937 genRand(randDevice());
39 std::uniform_int_distribution<int> disRand(randMin, randMax);
40 return disRand(genRand);
41 #endif
42 }
43
GenRandLongLong(int64_t randMin,int64_t randMax)44 int64_t GenRandLongLong(int64_t randMin, int64_t randMax)
45 {
46 std::random_device randDevice;
47 std::mt19937 genRand(randDevice());
48 std::uniform_int_distribution<long long> disRand(randMin, randMax);
49 return disRand(genRand);
50 }
51
GetRandomData(uint8_t * randStr,uint32_t len)52 int32_t GetRandomData(uint8_t *randStr, uint32_t len)
53 {
54 mbedtls_entropy_context *entropy = nullptr;
55 mbedtls_ctr_drbg_context *ctrDrbg = nullptr;
56 int32_t ret = ERR_DM_FAILED;
57 do {
58 if (randStr == nullptr || len == 0) {
59 break;
60 }
61 entropy = reinterpret_cast<mbedtls_entropy_context *>(malloc(sizeof(mbedtls_entropy_context)));
62 if (entropy == nullptr) {
63 break;
64 }
65 ctrDrbg = reinterpret_cast<mbedtls_ctr_drbg_context *>(malloc(sizeof(mbedtls_ctr_drbg_context)));
66 if (ctrDrbg == nullptr) {
67 break;
68 }
69 mbedtls_ctr_drbg_init(ctrDrbg);
70 mbedtls_entropy_init(entropy);
71 ret = mbedtls_ctr_drbg_seed(ctrDrbg, mbedtls_entropy_func, entropy, nullptr, 0);
72 if (ret != 0) {
73 break;
74 }
75 ret = mbedtls_ctr_drbg_random(ctrDrbg, randStr, len);
76 if (ret != 0) {
77 break;
78 }
79 ret = DM_OK;
80 } while (false);
81 if (entropy != nullptr) {
82 free(entropy);
83 entropy = nullptr;
84 }
85 if (ctrDrbg != nullptr) {
86 free(ctrDrbg);
87 ctrDrbg = nullptr;
88 }
89 return ret;
90 }
91 } // namespace DistributedHardware
92 } // namespace OHOS
93