1# 使用ECDSA密钥对验签(C/C++)
2
3
4对应的算法规格请查看[签名验签算法规格：ECDSA](crypto-sign-sig-verify-overview.md#ecdsa)。
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
15
161. 调用[OH_CryptoVerify_Create](../../reference/apis-crypto-architecture-kit/_crypto_signature_api.md#oh_cryptoverify_create)，指定字符串参数'ECC256|SHA256'，创建非对称密钥类型为ECC256、摘要算法为SHA256的Verify实例，用于完成验签操作。
17
182. 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。
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203. 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。
21   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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234. 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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25
26
27```c++
28#include "CryptoArchitectureKit/crypto_common.h"
29#include "CryptoArchitectureKit/crypto_signature.h"
30#include "CryptoArchitectureKit/crypto_asym_key.h"
31
32static bool doTestEcdsaSignature()
33{
34   OH_CryptoAsymKeyGenerator *keyCtx = nullptr;
35   OH_CryptoKeyPair *keyPair = nullptr;
36   OH_CryptoVerify *verify = nullptr;
37
38   uint8_t plainText[] = {
39      0xe4, 0x2b, 0xcc, 0x08, 0x11, 0x79, 0x16, 0x1b, 0x35, 0x7f, 0xb3, 0xaf, 0x40, 0x3b, 0x3f, 0x7c
40   };
41   Crypto_DataBlob msgBlob = {
42      .data = reinterpret_cast<uint8_t *>(plainText),
43      .len = sizeof(plainText)
44   };
45
46   uint8_t pubKeyText[] = {
47      0x30, 0x39, 0x30, 0x13, 0x06, 0x07, 0x2a, 0x86, 0x48, 0xce, 0x3d, 0x02, 0x01, 0x06, 0x08, 0x2a,
48      0x86, 0x48, 0xce, 0x3d, 0x03, 0x01, 0x07, 0x03, 0x22, 0x00, 0x03, 0x4d, 0xe4, 0xbb, 0x11, 0x10,
49      0x1a, 0xd2, 0x05, 0x74, 0xf1, 0x0b, 0xb4, 0x75, 0x57, 0xf4, 0x3e, 0x55, 0x14, 0x17, 0x05, 0x4a,
50      0xb2, 0xfb, 0x8c, 0x84, 0x64, 0x38, 0x02, 0xa0, 0x2a, 0xa6, 0xf0
51   };
52
53   Crypto_DataBlob keyBlob = {
54      .data = reinterpret_cast<uint8_t *>(pubKeyText),
55      .len = sizeof(pubKeyText)
56   };
57
58   uint8_t signText[] = {
59      0x30, 0x44, 0x02, 0x20, 0x21, 0x89, 0x99, 0xb1, 0x56, 0x4e, 0x3a, 0x2c, 0x16, 0x08, 0xb5, 0x8a,
60      0x06, 0x6f, 0x67, 0x47, 0x1b, 0x04, 0x18, 0x7d, 0x53, 0x2d, 0xba, 0x00, 0x38, 0xd9, 0xe3, 0xe7,
61      0x8c, 0xcf, 0x76, 0x83, 0x02, 0x20, 0x13, 0x54, 0x84, 0x9d, 0x73, 0x40, 0xc3, 0x92, 0x66, 0xdc,
62      0x3e, 0xc9, 0xf1, 0x4c, 0x33, 0x84, 0x2a, 0x76, 0xaf, 0xc6, 0x61, 0x84, 0x5c, 0xae, 0x4b, 0x0d,
63      0x3c, 0xb0, 0xc8, 0x04, 0x89, 0x71
64   };
65
66   Crypto_DataBlob signBlob = {
67      .data = reinterpret_cast<uint8_t *>(signText),
68      .len = sizeof(signText)
69   };
70
71   OH_Crypto_ErrCode ret = CRYPTO_SUCCESS;
72   // keypair
73   ret = OH_CryptoAsymKeyGenerator_Create((const char *)"ECC256", &keyCtx);
74   if (ret != CRYPTO_SUCCESS) {
75      return false;
76   }
77   ret = OH_CryptoAsymKeyGenerator_Convert(keyCtx, CRYPTO_DER, &keyBlob, nullptr, &keyPair);
78   if (ret != CRYPTO_SUCCESS) {
79      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
80      return false;
81   }
82   OH_CryptoPubKey *pubKey = OH_CryptoKeyPair_GetPubKey(keyPair);
83   // verify
84   ret = OH_CryptoVerify_Create((const char *)"ECC256|SHA256", &verify);
85   if (ret != CRYPTO_SUCCESS) {
86      OH_CryptoVerify_Destroy(verify);
87      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
88      return false;
89   }
90   ret = OH_CryptoVerify_Init(verify, pubKey);
91   if (ret != CRYPTO_SUCCESS) {
92      OH_CryptoVerify_Destroy(verify);
93      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
94      return false;
95   }
96   bool res = OH_CryptoVerify_Final(verify, &msgBlob, &signBlob);
97   if (res != true) {
98      OH_CryptoVerify_Destroy(verify);
99      OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
100      return false;
101   }
102
103   OH_CryptoVerify_Destroy(verify);
104   OH_CryptoAsymKeyGenerator_Destroy(keyCtx);
105   OH_CryptoKeyPair_Destroy(keyPair);
106   return res;
107}
108```
109