HarmonyOS鸿蒙Next中国密2公钥如何转字符串使用sm4加密后与服务端交互

根据编码规则可以自行提取https://support.huaweicloud.com/dew_faq/dew_01_0344.html。

【背景知识】 在数据存储或传输场景中，可以使用加解密操作用于保证数据的机密性，防止敏感数据泄露，加解密开发可参考加解密开发指导。 算法库当前提供了SM4加解密常用的7种加密模式：ECB、CBC、CTR、OFB、CFB、CFB128和GCM。 由于SM4为分组加密算法，分组长度为128位。在实际应用中，最后一组明文可能不足128位（16字节），此时可以通过不同的填充模式进行数据填充。

【解决方案】

• SM4加密代码如下：

  import { nfcController } from '@kit.ConnectivityKit';
  import { promptAction } from '@kit.ArkUI';
  import { cryptoFramework } from '@kit.CryptoArchitectureKit';
  import { buffer } from '@kit.ArkTS';
  
  @Entry
  @Component
  struct Index {
    build() {
      Column() {
        Text('SM4加密')
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
          .onClick(async()=>{
            const symAlgName = 'SM4_128'
            const sKey: string = '9f35eda67432c4ae3892305801b9d0b6';
            const symKeyData = buffer.from(sKey, 'hex')
            let symKeyBlob: cryptoFramework.DataBlob = { data: new Uint8Array(symKeyData.buffer) };
            try {
              let aesGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
              let symKey = await aesGenerator.convertKey(symKeyBlob);
              console.info(`wsf: sm4 转密钥成功`)
              let plainText: cryptoFramework.DataBlob = { data: new Uint8Array(buffer.from('This is a test', 'utf-8').buffer) };
              const cipher = cryptoFramework.createCipher('SM4_128|ECB|PKCS7')
              await cipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, symKey, null)
              const encryptData = await cipher.doFinal(plainText)
              console.info(`wsf: 加密成功`)
            } catch (e) {
              console.error(`wsf: 转密钥报错 e = ${e.code} ${e.message}`)
            }
          })
      }
      .height('100%')
      .width('100%')
    }
  }
  

• SM4解密代码如下：

  import { nfcController } from '@kit.ConnectivityKit';
  import { promptAction } from '@kit.ArkUI';
  import { cryptoFramework } from '@kit.CryptoArchitectureKit';
  import { buffer } from '@kit.ArkTS';
  
  @Entry
  @Component
  struct Index {
    build() {
      Column() {
        Text('SM4解密')
          .fontSize(50)
          .fontWeight(FontWeight.Bold)
          .onClick(async()=>{
            const symAlgName = 'SM4_128'
            const sKey: string = '9f35eda67432c4ae3892305801b9d0b6';
            const symKeyData = buffer.from(sKey, 'hex')
            let symKeyBlob: cryptoFramework.DataBlob = { data: new Uint8Array(symKeyData.buffer) };
            try {
              let aesGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
              let symKey = await aesGenerator.convertKey(symKeyBlob);
              let arr = [186,255,20,91,43,218,215,77,185,100,22,186,42,178,121,45];
              let dataAad = new Uint8Array(arr);
              let encryptData: cryptoFramework.DataBlob = { data: dataAad };
              let decoder = cryptoFramework.createCipher('SM4_128|ECB|PKCS7');
              await decoder.init(cryptoFramework.CryptoMode.DECRYPT_MODE, symKey, null);
              let decryptData = await decoder.doFinal(encryptData);
              console.info(`wsf: 解密成功 ${buffer.from(decryptData.data).toString()}`)
            } catch (e) {
              console.error(`wsf: 转密钥报错 e = ${e.code} ${e.message}`)
            }
          })
      }
      .height('100%')
      .width('100%')
    }
  }