1# Importing a Key in Plaintext (C/C++) 2 3 4This topic walks you through on how to import an ECC key. For details about the scenarios and supported algorithm specifications, see [Supported Algorithms](huks-key-import-overview.md#supported-algorithms). 5 6## Add the dynamic library in the CMake script. 7```txt 8 target_link_libraries(entry PUBLIC libhuks_ndk.z.so) 9``` 10 11## How to Develop 12 131. Set the alias **keyAlias** of the key to import. 14 The key alias cannot exceed 128 bytes. 15 162. Encapsulate the key property set and key material. Construct the key property set **paramSet** using [OH_Huks_InitParamSet](../../reference/apis-universal-keystore-kit/_huks_param_set_api.md#oh_huks_initparamset), [OH_Huks_AddParams](../../reference/apis-universal-keystore-kit/_huks_param_set_api.md#oh_huks_addparams), and [OH_Huks_BuildParamSet](../../reference/apis-universal-keystore-kit/_huks_param_set_api.md#oh_huks_buildparamset). 17 - ** paramSet** must contain [OH_Huks_KeyAlg](../../reference/apis-universal-keystore-kit/_huks_type_api.md#oh_huks_keyalg), [OH_Huks_KeySize](../../reference/apis-universal-keystore-kit/_huks_type_api.md#oh_huks_keysize), and [OH_Huks_KeyPurpose](../../reference/apis-universal-keystore-kit/_huks_type_api.md#oh_huks_keypurpose). 18 - The key material must comply with the [HUKS key material format](huks-concepts.md#key-material-format). 19 203. Use [OH_Huks_ImportKeyItem](../../reference/apis-universal-keystore-kit/_huks_key_api.md#oh_huks_importkeyitem) to import the key. 21 22```c++ 23/* Import an ECC key in plaintext. */ 24#include "huks/native_huks_api.h" 25#include "huks/native_huks_param.h" 26#include <string.h> 27OH_Huks_Result InitParamSet(struct OH_Huks_ParamSet **paramSet, const struct OH_Huks_Param *params, 28 uint32_t paramCount) { 29 OH_Huks_Result ret = OH_Huks_InitParamSet(paramSet); 30 if (ret.errorCode != OH_HUKS_SUCCESS) { 31 return ret; 32 } 33 ret = OH_Huks_AddParams(*paramSet, params, paramCount); 34 if (ret.errorCode != OH_HUKS_SUCCESS) { 35 OH_Huks_FreeParamSet(paramSet); 36 return ret; 37 } 38 ret = OH_Huks_BuildParamSet(paramSet); 39 if (ret.errorCode != OH_HUKS_SUCCESS) { 40 OH_Huks_FreeParamSet(paramSet); 41 return ret; 42 } 43 return ret; 44} 45struct OH_Huks_Param g_testImportKeyParam[] = {{.tag = OH_HUKS_TAG_ALGORITHM, .uint32Param = OH_HUKS_ALG_ECC}, 46 {.tag = OH_HUKS_TAG_PURPOSE, .uint32Param = OH_HUKS_KEY_PURPOSE_AGREE}, 47 {.tag = OH_HUKS_TAG_KEY_SIZE, .uint32Param = OH_HUKS_ECC_KEY_SIZE_256}, 48 {.tag = OH_HUKS_TAG_DIGEST, .uint32Param = OH_HUKS_DIGEST_NONE}}; 49 50static napi_value ImportKey(napi_env env, napi_callback_info info) { 51 const char *alias = "test_import"; 52 struct OH_Huks_Blob aliasBlob = {.size = (uint32_t)strlen(alias), .data = (uint8_t *)alias}; 53 /* Public key in DER format, which is used to import the key. */ 54 uint8_t pubKey[OH_HUKS_ECC_KEY_SIZE_256] = { 55 0x30, 0x2A, 0x30, 0x05, 0x06, 0x03, 0x2B, 0x65, 0x6E, 0x03, 0x21, 0x00, 0xD2, 0x36, 0x9E, 0xCF, 56 0xF0, 0x61, 0x5B, 0x73, 0xCE, 0x4F, 0xF0, 0x40, 0x2B, 0x89, 0x18, 0x3E, 0x06, 0x33, 0x60, 0xC6 57 }; 58 struct OH_Huks_Blob publicKey = {OH_HUKS_ECC_KEY_SIZE_256, pubKey}; 59 struct OH_Huks_ParamSet *testImportKeyParamSet = nullptr; 60 struct OH_Huks_Result ohResult; 61 do { 62 ohResult = InitParamSet(&testImportKeyParamSet, g_testImportKeyParam, 63 sizeof(g_testImportKeyParam) / sizeof(OH_Huks_Param)); 64 if (ohResult.errorCode != OH_HUKS_SUCCESS) { 65 break; 66 } 67 if (ohResult.errorCode != OH_HUKS_SUCCESS) { 68 break; 69 } 70 /* 4. Import Key */ 71 char newKey[] = "test_import"; 72 struct OH_Huks_Blob newKeyAlias = {.size = (uint32_t)strlen(newKey), .data = (uint8_t *)newKey}; 73 ohResult = OH_Huks_ImportKeyItem(&newKeyAlias, testImportKeyParamSet, &publicKey); 74 } while (0); 75 OH_Huks_FreeParamSet(&testImportKeyParamSet); 76 napi_value ret; 77 napi_create_int32(env, ohResult.errorCode, &ret); 78 return ret; 79} 80``` 81