签名/验签(ArkTS)

以密钥算法为ECC256、摘要算法为SHA256的密钥为例，完成签名、验签。具体的场景介绍及支持的算法规格，请参考签名/验签支持的算法。

开发步骤

生成密钥

1. 指定密钥别名。

2. 初始化密钥属性集。

3. 调用generateKeyItem生成密钥，具体请参考密钥生成。

除此之外，开发者也可以参考密钥导入，导入已有的密钥。

签名

1. 获取密钥别名。

2. 指定待签名的明文数据。

3. 获取属性参数HuksOptions，包括两个字段properties和inData。 inData传入明文数据，properties传入算法参数配置。

4. 调用initSession初始化密钥会话，并获取会话的句柄handle。

5. 调用finishSession结束密钥会话，获取签名signature。

验签

1. 获取密钥别名。

2. 获取待验证的签名signature。

3. 获取属性参数HuksOptions，包括两个字段properties和inData。 inData传入签名signature，properties传入算法参数配置。

4. 调用initSession初始化密钥会话，并获取会话的句柄handle。

5. 调用updateSession更新密钥会话。

6. 调用finishSession结束密钥会话，验证签名。

删除密钥

当密钥废弃不用时，需要调用deleteKeyItem删除密钥，具体请参考密钥删除。

/*
 * 以ECC 256 DIGEST SHA256密钥的Promise操作使用为例
 */
import huks from '@ohos.security.huks';
import { BusinessError } from '@ohos.base';
let keyAlias = 'test_eccKeyAlias';
let handle: number;
let plaintext = '123456';
let signature: Uint8Array;
function StringToUint8Array(str: String) {
  let arr:number[]=new Array();
  for (let i = 0, j = str.length; i < j; ++i) {
    arr.push(str.charCodeAt(i));
  }
  return new Uint8Array(arr);
}
function Uint8ArrayToString(fileData: Uint8Array) {
  let dataString = '';
  for (let i = 0; i < fileData.length; i++) {
    dataString += String.fromCharCode(fileData[i]);
  }
  return dataString;
}
function GetEccGenerateProperties() {
  let properties: Array<huks.HuksParam> = new Array();
  let index = 0;
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
    value: huks.HuksKeyAlg.HUKS_ALG_ECC
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_KEY_SIZE,
    value: huks.HuksKeySize.HUKS_AES_KEY_SIZE_256
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_PURPOSE,
    value: huks.HuksKeyPurpose.HUKS_KEY_PURPOSE_SIGN |
    huks.HuksKeyPurpose.HUKS_KEY_PURPOSE_VERIFY
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_DIGEST,
    value: huks.HuksKeyDigest.HUKS_DIGEST_SHA256
  }
  return properties;
}
function GetEccSignProperties() {
  let properties: Array<huks.HuksParam> = new Array();
  let index = 0;
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
    value: huks.HuksKeyAlg.HUKS_ALG_ECC
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_KEY_SIZE,
    value: huks.HuksKeySize.HUKS_AES_KEY_SIZE_256
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_PURPOSE,
    value: huks.HuksKeyPurpose.HUKS_KEY_PURPOSE_SIGN
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_DIGEST,
    value: huks.HuksKeyDigest.HUKS_DIGEST_SHA256
  }
  return properties;
}
function GetEccVerifyProperties() {
  let properties: Array<huks.HuksParam> = new Array();
  let index = 0;
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_ALGORITHM,
    value: huks.HuksKeyAlg.HUKS_ALG_ECC
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_KEY_SIZE,
    value: huks.HuksKeySize.HUKS_AES_KEY_SIZE_256
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_PURPOSE,
    value: huks.HuksKeyPurpose.HUKS_KEY_PURPOSE_VERIFY
  };
  properties[index++] = {
    tag: huks.HuksTag.HUKS_TAG_DIGEST,
    value: huks.HuksKeyDigest.HUKS_DIGEST_SHA256
  }
  return properties;
}
async function GenerateEccKey(keyAlias: string) {
  let genProperties = GetEccGenerateProperties();
  let options: huks.HuksOptions = {
    properties: genProperties
  }
  await huks.generateKeyItem(keyAlias, options)
    .then((data) => {
      console.info(`promise: generate ECC Key success, data = ${JSON.stringify(data)}`);
    }).catch((err: BusinessError)=>{
      console.error(`promise: generate ECC Key failed, error: ` + JSON.stringify(err));
    })
}
async function Sign(keyAlias: string, plaintext: string) {
  let signProperties = GetEccSignProperties();
  let options: huks.HuksOptions = {
    properties: signProperties,
    inData: StringToUint8Array(plaintext)
  }
  await huks.initSession(keyAlias, options)
    .then((data) => {
      handle = data.handle;
    }).catch((err: BusinessError)=>{
      console.error(`promise: init sign failed, error: ` + JSON.stringify(err));
    })
  await huks.finishSession(handle, options)
    .then((data) => {
      console.info(`promise: sign success, data is `+ Uint8ArrayToString(data.outData as Uint8Array));
      signature = data.outData as Uint8Array;
    }).catch((err: BusinessError)=>{
      console.error(`promise: sign failed, error: ` + JSON.stringify(err));
    })
}
async function Verify(keyAlias: string, plaintext: string, signature: Uint8Array) {
  let verifyProperties = GetEccVerifyProperties()
  let options: huks.HuksOptions = {
    properties: verifyProperties,
    inData: StringToUint8Array(plaintext)
  }
  await huks.initSession(keyAlias, options)
    .then((data) => {
      handle = data.handle;
    }).catch((err: BusinessError)=>{
      console.error(`promise: init verify failed, error: ` + JSON.stringify(err));
    })
  await huks.updateSession(handle, options)
    .then((data) => {
      console.info(`promise: update verify success, data is ` + Uint8ArrayToString(data.outData as Uint8Array));
    }).catch((err: BusinessError)=>{
      console.error(`promise: update verify failed, error: ` + JSON.stringify(err));
    })
  options.inData = signature;
  await huks.finishSession(handle, options)
    .then((data) => {
      console.info(`promise: verify success, data is ` + Uint8ArrayToString(data.outData as Uint8Array));
    }).catch((err: BusinessError)=>{
      console.error(`promise: verify failed, error: ` + JSON.stringify(err));
    })
}
async function DeleteEccKey(keyAlias: string) {
  let emptyOptions: huks.HuksOptions = {
    properties: []
  }
  await huks.deleteKeyItem(keyAlias, emptyOptions)
    .then((data) => {
      console.info(`promise: delete data success`);
    }).catch((err: BusinessError)=>{
      console.error(`promise: delete data failed`);
    })
}
async function testSignVerify() {
  await GenerateEccKey(keyAlias);
  await Sign(keyAlias, plaintext);
  await Verify(keyAlias, plaintext, signature);
  await DeleteEccKey(keyAlias);
}