Csharp 当通过Google的Gmail Api发送邮件时，签名会产生dkim = neutral(正文散列未验证)'

我们正在try 与DKIM签署一封邮箱.邮箱通过Gmail的Api成功发送给收件人；然而，当我们使用具有有效DKIM设置的域对其进行签名时，它将无法通过DKIM验证. 该域具有有效的DKIM设置(https://mxtoolbox.com/SuperTool.aspx?action=dkim%3aunsub.eeunsub.com%3as1&run=toolpage)，当我们使用其他邮箱Provider (如AWS SES)发送邮箱时，DKIM通过(添加了屏幕截图，见下文).

private static void SendEmail()
{
  ClientSecrets clientSecrets = new ClientSecrets
  {
      ClientId = ClientId,
      ClientSecret = ClientSecret
  };
  
  TokenResponse token = new TokenResponse
  {
      AccessToken = "",
      RefreshToken = _espApiEndpoint.RefreshToken
  };
  
  IAuthorizationCodeFlow flow =
  new GoogleAuthorizationCodeFlow(new GoogleAuthorizationCodeFlow.Initializer
  {
      ClientSecrets = clientSecrets,
      Scopes = new string[] { GmailService.Scope.GmailSend }
  });
  
  UserCredential credential = new UserCredential(flow, "me", token);
  
  BaseClientService.Initializer intializer = new BaseClientService.Initializer
  {
      ApplicationName = "GmailEspApiClient",
      HttpClientInitializer = credential
  };
  
  var gmail = new GmailService(intializer);
  
  string message = @"From: Xxx <xxx@gmail.com>
  Date: Thu, 14 Mar 2024 09:59:20 -0700
  Subject: Gmail EE est
  Message-Id: <33@xxx.com>
  Reply-To: xxx <xxx@xxx.com>
  To: Dan <xxx@xxx.com>
  X-EE-RunId: xxx
  List-Unsubscribe: <xxx.com/>, <mailto:>
  List-Unsubscribe-Post: List-Unsubscribe=One-Click
  X-Test-Header: TestHeader
  X-Testing: Testee
  MIME-Version: 1.0
  Content-Type: text/html; charset=utf-8
  
  Hello from <b>Gmail</b>
  ";
  
  using MemoryStream memoryStream = new MemoryStream(System.Text.Encoding.UTF8.GetBytes(message));
  MimeMessage mimeMessage = await MimeMessage.LoadAsync(memoryStream);
  
  string privateKey = ""; // Your private key
  byte[] byteArray = Encoding.UTF8.GetBytes(privateKey);
  using MemoryStream memory = new MemoryStream(byteArray);
  
  string domain = "xxx"; // Your Domain
  string selector = "xxx"; // Selector
  DkimSigner signer = new DkimSigner(memory, domain, selector)
  {
      HeaderCanonicalization算法rithm = DkimCanonicalization算法rithm.Simple,
      BodyCanonicalization算法rithm = DkimCanonicalization算法rithm.Simple,
      QueryMethod = "dns/txt",
  };
  
  mimeMessage.Prepare(EncodingConstraint.SevenBit);
  
  signer.Sign(mimeMessage, new HeaderId[] { HeaderId.From });
  
  Message finalmessage = new Message();
  finalmessage.Raw = Base64UrlEncode(mimeMessage.ToString());
  var result = await gmail.Users.Messages.Send(finalmessage, "me").ExecuteAsync();
}

private static string Base64UrlEncode(string input)
{
    var inputBytes = System.Text.Encoding.UTF8.GetBytes(input);;
    // Special "url-safe" base64 encode.
    return Convert.ToBase64String(inputBytes)
      .Replace('+', '-')
      .Replace('/', '_')
      .Replace("=", "");
}

Google和Aws SES的屏幕截图都有.请注意谷歌如何返回dkim=neutral (body hash did not verify).

请让我们知道你的 idea .

以前使用Google https://github.com/googleapis/google-api-dotnet-client/issues/2701打开的问题