一段 object c 代码想转 Swift ，有什么方法吗？

- (NSData *)AES256EncryptWithKey:(NSString *)key {     NSUInteger dataLength = [self length];     size_t bufferSize = dataLength + kCCBlockSizeAES128;     void *buffer = malloc(bufferSize);     NSMutableData *data = [[NSData randomDataWithLength:AES_256_IV_SIZE] mutableCopy];  //IV          size_t numBytesEncrypted = 0;     CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,                                           kCCAlgorithmAES128,                                           kCCOptionPKCS7Padding,                                           [key cStringUsingEncoding:NSUTF8StringEncoding],                                           [key length],                                           [data bytes],                                           [self bytes],                                           dataLength,                                           buffer,                                           bufferSize,                                           &numBytesEncrypted);               if (cryptStatus == kCCSuccess) {         NSData *message = [NSData dataWithBytes:buffer                                          length:numBytesEncrypted]; //Message         /* Do HMac */         NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];         NSData *hmac = [message doHmacWithKeyData:keyData];          /* IV+Message+HMac */         [data appendData:message];         [data appendData:hmac];          free(buffer);         return data;     }     free(buffer);     return nil; }  - (NSData *)doHmacWithKeyData:(NSData *)salt {     NSMutableData *macOut = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];     CCHmac(kCCHmacAlgSHA256,            salt.bytes,            salt.length,            self.bytes,            self.length,            macOut.mutableBytes);          return macOut; } 

• 資深大佬 : finab

  https://swiftify.com/converter/code/
  这个可以将 Objc 代码转成 Swift，可能会有一些错误，需要修改。

• 資深大佬 : CommandZi

  https://github.com/onmyway133/Arcane/blob/master/Sources/Arcane/AES.swift

• 資深大佬 : chiaf

  @finab 这个不错，需要注意的地方，非登录情况下，支持 1K 以下的代码

• 主 資深大佬 : chillwind

  看了半天 swift，自己人肉转了一个。用的不对的地方，还请各位指正
  “`
  import Foundation
  import CommonCrypto

  struct AES {

  // MARK: – Value
  // MARK: Private
  private let key: Data
  // MARK: – Initialzier
  init?(key: String) {
  guard key.count == kCCKeySizeAES128 || key.count == kCCKeySizeAES256, let keyData = key.data(using: .utf8) else {
  debugPrint(“Error: Failed to set a key.”)
  return nil
  }

  self.key = keyData

  }

  // MARK: – Function
  // MARK: Public
  func encrypt(string: String) -> Data? {

  let iv = randomGenerateBytes(count: 16)!

  let cryptData = crypt(data: string.data(using: .utf8), iv: iv, option: CCOperation(kCCEncrypt))!

  var hmac = Data(count: 32)
  cryptData.withUnsafeBytes { v in
  hmac.withUnsafeMutableBytes { res in
  key.withUnsafeBytes { k in
  CCHmac(CCHmacAlgorithm(kCCHmacAlgSHA256), k.baseAddress!, key.count, v.baseAddress!, cryptData.count, res.baseAddress!)
  }
  }
  }

  let messageData = NSMutableData()
  messageData.append(iv)
  messageData.append(cryptData)
  messageData.append(hmac)

  return messageData as Data
  }

  func decrypt(data: Data) -> String? {
  //验证数据
  let ivByteData = data.subdata(in: 0..<16)

  let contentByteData = data.subdata(in: 16..<(data.count – 32))

  let serverHmacData = data.subdata(in: (data.count – 32)..<data.count)
  print(data.count)

  var hmac = Data(count: 32)
  contentByteData.withUnsafeBytes { v in
  hmac.withUnsafeMutableBytes { res in
  key.withUnsafeBytes { k in
  CCHmac(CCHmacAlgorithm(kCCHmacAlgSHA256), k.baseAddress!, key.count, v.baseAddress!, contentByteData.count, res.baseAddress!)
  }
  }
  }

  if (serverHmacData == hmac) {
  let decryptedData = crypt(data: contentByteData, iv: ivByteData, option: CCOperation(kCCDecrypt))
  return String(bytes: decryptedData!, encoding: .utf8)
  } else {
  print(“HMac 不一致”)
  return nil;
  }

  }

  func crypt(data: Data?, iv: Data, option: CCOperation) -> Data? {
  guard let data = data else { return nil }

  let cryptLength = data.count + kCCBlockSizeAES128*2
  var cryptData = Data(count: cryptLength)

  let keyLength = key.count
  let options = CCOptions(kCCOptionPKCS7Padding)

  var bytesLength = Int(0)

  let status = cryptData.withUnsafeMutableBytes { cryptBytes in
  data.withUnsafeBytes { dataBytes in
  iv.withUnsafeBytes { ivBytes in
  key.withUnsafeBytes { keyBytes in
  CCCrypt(option, CCAlgorithm(kCCAlgorithmAES128), options, keyBytes.baseAddress, keyLength, ivBytes.baseAddress, dataBytes.baseAddress, data.count, cryptBytes.baseAddress, cryptLength, &bytesLength)
  }
  }
  }
  }

  guard UInt32(status) == UInt32(kCCSuccess) else {
  debugPrint(“Error: Failed to crypt data. Status (status)”)
  return nil
  }

  cryptData.removeSubrange(bytesLength..<cryptData.count)

  return cryptData
  }

  func randomGenerateBytes(count: Int) -> Data? {
  let bytes = UnsafeMutableRawPointer.allocate(byteCount: count, alignment: 1)
  defer { bytes.deallocate() }
  let status = CCRandomGenerateBytes(bytes, count)
  guard status == kCCSuccess else { return nil }
  return Data(bytes: bytes, count: count)
  }
  }

  “`

• 資深大佬 : zyc199847

  swift 的话，可以试试原生的 CryptoSwift 。https://github.com/krzyzanowskim/CryptoSwift