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