HarmonyOS 开发中针对流形式文件（zip文件）AES解密，再zip解压？

Question

HarmonyOS 开发中针对流形式文件（zip文件）AES解密，再zip解压？后端接口下发一个zip二进制文件，aes加密过的；然后在客户端需要用aes解密，然后再对zip解压。zip解压有api：ohos.zlib可以实现。请问针对aes加密的zip文件有方法可以解密吗？

Answer 1

可以将文件转为二进制数组传入加解密方法中可以进行加密和解密操作，具体代码参考：

/*加密*/ 
export async function aesEncrypt(text:Uint8Array,puKey:string): Promise<string>{ 
  let globalResult = "" 
  try { 
    let cipherAlgName = 'AES128|ECB|PKCS7'; 
    let globalCipher = cryptoFramework.createCipher(cipherAlgName); 
    let symAlgName = 'AES128'; 
    let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName); 
    let dataUint8Array = base.decodeSync(puKey) 
    let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array } 
    let promiseSymKey = await symKeyGenerator.convertKey(keyBlob) 
    await globalCipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, promiseSymKey, null); 
    let result = await globalCipher.doFinal({data:text}) 
    globalResult = base.encodeToStringSync(result.data); 
  } catch (err) { 
    console.log(err.message) 
  } 
  return globalResult; 
} 
 
// 解密 
export async function aesDecrypt(text: string, key: string) { 
  let globalResult = "" 
  try { 
    let cipherAlgName = 'AES128|ECB|PKCS7'; 
    let globalCipher = cryptoFramework.createCipher(cipherAlgName); 
    let symAlgName = 'AES128'; 
    let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName); 
    let dataUint8Array = base.decodeSync(key) 
    let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array } 
    let promiseSymKey = await symKeyGenerator.convertKey(keyBlob) 
    await globalCipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, promiseSymKey, null); 
    let plainText: cryptoFramework.DataBlob = { data: base.decodeSync(text) } 
    let result = await globalCipher.doFinal(plainText)//解密结果 
  } catch (err) { 
    console.log(err.message) 
  } 
  return globalResult; 
}

对于加解密的规格和密钥规格可以参考：
https://developer.huawei.com/consumer/cn/doc/harmonyos-guides...
https://developer.huawei.com/consumer/cn/doc/harmonyos-guides...
可以读取文件信息，获知文件大小size：
https://developer.huawei.com/consumer/cn/doc/harmonyos-refere...
再自行按定长读取文件内容，分段AES解密
https://developer.huawei.com/consumer/cn/doc/harmonyos-refere...

/** 
 * aes文件加密 
 */ 
function encryptFile(srcPath, outPath) { 
  return new Promise(resolve => { 
    try { 
      if (!srcPath || !outPath) { 
        return resolve({code: 0, message: '路径srcPath或outPath为空！'}); 
      } 
      /* 
      * outPath:'/Users/xxx/WorkSpace/zt-repository/offline-pack-platform/pack-server/uploads/online/encrypt/aeron/using.zip 
      * ///opt/cephfs_workspace/h5-offline/uploads/online/encrypt/commonRes/UahFgeGd/v10003 
      * 首先去除文件名再创建目录 
      * */ 
      let len = outPath.lastIndexOf('/'); 
      let outDir = outPath.substr(0, len); 
      fse.ensureDir(outDir, (err) => { 
        if (err) { 
          return resolve({code: 0, message: `创建目录${outDir}失败:${err.message}`}); 
        } 
 
        const keyVi = getCbcKeyVi(); 
        console.log('keyVi=', keyVi,srcPath,outPath); 
        const cipher = crypto.createCipheriv(__algorithm__, keyVi.key, keyVi.vi); 
        const rs = fs.createReadStream(srcPath); 
        const ws = fs.createWriteStream(outPath); 
        //console.log(111111,cipher) 
        rs.pipe(cipher) 
          .pipe(ws) 
          .on('error', function (err) { 
            console.log(`encryptFile err:${err.message}`); 
            return resolve({ 
              code: 0, 
              path: null, 
              msg: err && err.message 
            }); 
          }) 
          .on(`finish`, function () { 
            console.log(`encryptFile done!`); 
            return resolve({ 
              code: 1, 
              path: outPath 
            }); 
          }); 
      }); 
    } catch (err) { 
      return resolve({ 
        code: 0, 
        path: null, 
        msg: err.message 
      }); 
    } 
  }); 
} 
 
/** 
 * aes文件解密 
 */ 
function decryptFile(srcPath, outPath) { 
  const keyVi = getCbcKeyVi(); 
  //console.log('keyVi=', keyVi); 
 
  const deS = crypto.createCipheriv(__algorithm__, keyVi.key, keyVi.vi); 
  const rs = fs.createReadStream(srcPath); 
  const ws = fs.createWriteStream(outPath); 
 
  rs.pipe(deS) 
    .pipe(ws) 
    .on('error', function (err) { 
      console.log(`decryptFile err:${err.message}`)}

类似JS的原生方法如上所示可以参考：https://developer.huawei.com/consumer/cn/doc/harmonyos-refere...