1# 使用RSA密钥对（PKCS1模式）验签(C/C++)
2
3
4对应的算法规格请查看[验签算法规格：RSA](crypto-sign-sig-verify-overview.md#rsa)。
5
6
7## 在CMake脚本中链接相关动态库
8```txt
9   target_link_libraries(entry PUBLIC libohcrypto.so)
10```
11
12## 开发步骤
13
14
151. 调用[OH_CryptoVerify_Create](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_create)，指定字符串参数'RSA1024|PKCS1|SHA256'，与签名的Sign实例保持一致。创建Verify实例，用于完成验签操作。
16
172. 调用[OH_CryptoVerify_Init](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_init)，使用公钥（OH_CryptoPubKey）初始化Verify实例。
18
193. 调用[OH_CryptoVerify_Update](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_update)，传入待验证的数据。
20   当前单次update长度没有限制，开发者可以根据数据量判断如何调用update，如果数据量较小，可以直接调用OH_CryptoVerify_Final接口一次性传入。
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22   - 当待签名的数据较短时，可以在init完成后直接调用[OH_CryptoVerify_Final](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_final)。
23   - 当数据量较大时，可以多次调用update，即[分段验签](crypto-rsa-sign-sig-verify-pkcs1-by-segment-ndk.md)。
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254. 调用[OH_CryptoVerify_Final](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_final)，对数据进行验签。
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27
28- 示例：
29
30```c++
31#include "CryptoArchitectureKit/crypto_common.h"
32#include "CryptoArchitectureKit/crypto_asym_key.h"
33
34static bool doTestRsaSignature()
35{
36   OH_CryptoAsymKeyGenerator *keyCtx = nullptr;
37   OH_CryptoKeyPair *keyPair = nullptr;
38   OH_CryptoVerify *verify = nullptr;
39
40   uint8_t plainText[] = {
41      0x43, 0x31, 0x7d, 0xb5, 0x85, 0x2e, 0xd4, 0xef, 0x08, 0x7a, 0x17, 0x96, 0xbc, 0x7c, 0x8f, 0x80,
42      0x8c, 0xa7, 0x63, 0x7f, 0x26, 0x89, 0x8f, 0xf0, 0xfa, 0xa7, 0x51, 0xbd, 0x9c, 0x69, 0x17, 0xf3,
43      0xd1, 0xb5, 0xc7, 0x12, 0xbf, 0xcf, 0x91, 0x25, 0x82, 0x23, 0x6b, 0xd6, 0x64, 0x52, 0x77, 0x93,
44      0x01, 0x9d, 0x70, 0xa3, 0xf4, 0x92, 0x16, 0xec, 0x3f, 0xa7, 0x3c, 0x83, 0x8d, 0x40, 0x41, 0xfc,
45   };
46   Crypto_DataBlob msgBlob = {
47      .data = reinterpret_cast<uint8_t *>(plainText),
48      .len = sizeof(plainText)
49   };
50
51   uint8_t pubKeyText[] = {
52      0x2d, 0x2d, 0x2d, 0x2d, 0x2d, 0x42, 0x45, 0x47, 0x49, 0x4e, 0x20, 0x52, 0x53, 0x41, 0x20, 0x50,
53      0x55, 0x42, 0x4c, 0x49, 0x43, 0x20, 0x4b, 0x45, 0x59, 0x2d, 0x2d, 0x2d, 0x2d, 0x2d, 0x0a, 0x4d,
54      0x49, 0x47, 0x4a, 0x41, 0x6f, 0x47, 0x42, 0x41, 0x4d, 0x78, 0x63, 0x44, 0x4d, 0x6f, 0x61, 0x59,
55      0x52, 0x58, 0x6f, 0x78, 0x65, 0x69, 0x33, 0x49, 0x6d, 0x33, 0x33, 0x78, 0x4a, 0x76, 0x61, 0x73,
56      0x63, 0x43, 0x62, 0x77, 0x31, 0x6f, 0x73, 0x63, 0x32, 0x56, 0x56, 0x69, 0x47, 0x6a, 0x56, 0x47,
57      0x47, 0x4a, 0x37, 0x6c, 0x75, 0x4e, 0x41, 0x58, 0x6b, 0x6a, 0x73, 0x56, 0x46, 0x64, 0x35, 0x0a,
58      0x58, 0x37, 0x4c, 0x4d, 0x6c, 0x46, 0x34, 0x63, 0x35, 0x5a, 0x75, 0x59, 0x2f, 0x61, 0x69, 0x57,
59      0x77, 0x70, 0x54, 0x69, 0x63, 0x62, 0x67, 0x49, 0x33, 0x43, 0x66, 0x50, 0x6f, 0x32, 0x6a, 0x6c,
60      0x52, 0x74, 0x67, 0x41, 0x46, 0x6b, 0x44, 0x71, 0x7a, 0x4b, 0x53, 0x46, 0x62, 0x46, 0x47, 0x51,
61      0x6b, 0x43, 0x6e, 0x64, 0x63, 0x2b, 0x54, 0x59, 0x6b, 0x5a, 0x42, 0x32, 0x70, 0x45, 0x6f, 0x72,
62      0x0a, 0x7a, 0x73, 0x61, 0x56, 0x58, 0x77, 0x5a, 0x47, 0x45, 0x34, 0x41, 0x43, 0x70, 0x59, 0x35,
63      0x79, 0x65, 0x66, 0x49, 0x44, 0x6c, 0x45, 0x57, 0x49, 0x51, 0x4f, 0x6a, 0x59, 0x4b, 0x2f, 0x6c,
64      0x58, 0x71, 0x7a, 0x48, 0x47, 0x69, 0x4f, 0x69, 0x32, 0x75, 0x4a, 0x45, 0x75, 0x44, 0x43, 0x50,
65      0x6a, 0x51, 0x64, 0x6a, 0x54, 0x41, 0x67, 0x4d, 0x42, 0x41, 0x41, 0x45, 0x3d, 0x0a, 0x2d, 0x2d,
66      0x2d, 0x2d, 0x2d, 0x45, 0x4e, 0x44, 0x20, 0x52, 0x53, 0x41, 0x20, 0x50, 0x55, 0x42, 0x4c, 0x49,
67      0x43, 0x20, 0x4b, 0x45, 0x59, 0x2d, 0x2d, 0x2d, 0x2d, 0x2d, 0x0a,
68   };
69
70   Crypto_DataBlob keyBlob = {
71      .data = reinterpret_cast<uint8_t *>(pubKeyText),
72      .len = sizeof(pubKeyText)
73   };
74
75   uint8_t signText[] = {
76      0x68, 0x2f, 0x3b, 0xe6, 0xa6, 0x5c, 0xb8, 0x60, 0xd4, 0xe1, 0x64, 0xa7, 0xd8, 0x0c, 0x9c, 0x89,
77      0x39, 0xb4, 0xf0, 0xb7, 0xad, 0xb5, 0x8a, 0x71, 0x04, 0xf1, 0xa5, 0x63, 0xdd, 0x32, 0x6a, 0x44,
78      0xeb, 0xff, 0xb7, 0xe6, 0x85, 0xe5, 0xa5, 0x55, 0x5d, 0x5b, 0x28, 0x53, 0x63, 0xe4, 0xb3, 0xb9,
79      0xa8, 0x70, 0xc8, 0x8f, 0xcd, 0x21, 0x8d, 0xe6, 0x1f, 0xe5, 0x78, 0x34, 0xd3, 0x45, 0x0c, 0x9c,
80      0x7a, 0x22, 0x1b, 0x63, 0x55, 0xca, 0x14, 0xa5, 0x0c, 0x7a, 0x40, 0x8e, 0xa1, 0x14, 0x78, 0xa1,
81      0xf1, 0x36, 0x78, 0xbd, 0xba, 0x37, 0x3b, 0x5b, 0xb0, 0x8e, 0xb3, 0x4a, 0x9b, 0x1b, 0x0c, 0xfa,
82      0xfa, 0xc7, 0x9f, 0xb1, 0x35, 0x48, 0x82, 0x73, 0xf8, 0x6b, 0xd4, 0x76, 0x33, 0x5c, 0xed, 0x9c,
83      0xd8, 0x4b, 0xc9, 0x92, 0xa0, 0x3f, 0x6e, 0xba, 0x78, 0x2e, 0x80, 0x78, 0x1e, 0x74, 0xa0, 0x47,
84   };
85
86   Crypto_DataBlob signBlob = {
87      .data = reinterpret_cast<uint8_t *>(signText),
88      .len = sizeof(signText)
89   };
90
91   // keypair
92   OH_Crypto_ErrCode ret = CRYPTO_SUCCESS;
93   ret = OH_CryptoAsymKeyGenerator_Create((const char *)"RSA2048", &keyCtx);
94   if (ret != CRYPTO_SUCCESS) {
95      return false;
96   }
97   ret = OH_CryptoAsymKeyGenerator_Convert(keyCtx, CRYPTO_PEM, &keyBlob, nullptr, &keyPair);
98   if (ret != CRYPTO_SUCCESS) {
99      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
100      return false;
101   }
102   OH_CryptoPubKey *pubKey = OH_CryptoKeyPair_GetPubKey(keyPair);
103   // verify
104   ret = OH_CryptoVerify_Create((const char *)"RSA1024|PKCS1|SHA256", &verify);
105   if (ret != CRYPTO_SUCCESS) {
106      OH_CryptoVerify_Destroy(verify);
107      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
108      return false;
109   }
110   ret = OH_CryptoVerify_Init(verify, pubKey);
111   if (ret != CRYPTO_SUCCESS) {
112      OH_CryptoVerify_Destroy(verify);
113      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
114      return false;
115   }
116   bool res = OH_CryptoVerify_Final(verify, &msgBlob, &signBlob);
117   if (res != true) {
118      OH_CryptoVerify_Destroy(verify);
119      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
120      return false;
121   }
122
123   OH_CryptoVerify_Destroy(verify);
124   OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
125   OH_CryptoKeyPair_Destroy(keyPair);
126   return res;
127}
128```
129