email - 无法使用 Delphi 从 Gmail 帐户下载/检索电子邮件 (SSL3_GET_RECORD :wrong version number)

Question

我无法使用 Delphi + Indy 从 Gmail 下载/检索电子邮件!

几个星期以来，我无法阅读来自 Gmail 的电子邮件。

在下面的代码正常工作之前。

现在，我总是收到此错误消息:

error:1408F10B:SSL routines:SSL3_GET_RECORD:wrong version number

在连接到 Gmail 期间。

关于 Cryptosense Blog我读了

As trailed back in September 2015, Google are turning off SSLv3 and RC4 support from their TLS servers.

有什么解决方案可以立即阅读来自 Gmail 的电子邮件吗？

我的代码是这样的:

1. 开始一个新的 Delphi 项目

2. 您必须从此站点下载 SSL dll:

http://indy.fulgan.com/SSL/indy_OpenSSL096m.zip

1. 解压缩文件并将 libeay32.dll 和 ssleay32.dll 放入您的项目路径。

2. 用下面的代码替换Unit1.pas和Unit1.dfm的代码

3. 更改 POP3 组件上的用户名和密码属性以匹配您的 GMAIL 帐户。

4. 运行它

//代码开始

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, IdBaseComponent, IdComponent, IdTCPConnection,
  IdTCPClient, IdExplicitTLSClientServerBase, IdMessageClient, IdPOP3,
  IdIOHandler, IdIOHandlerSocket, IdIOHandlerStack, IdSSL, IdSSLOpenSSL;

type
  TForm1 = class(TForm)
    POP3: TIdPOP3;
    Button1: TButton;
    SSLHandler: TIdSSLIOHandlerSocketOpenSSL;
    Memo1: TMemo;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

uses
  IdMessage, IdText;

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  lMsg: TIdMessage;
  liCount: Integer;
  liMessages: Integer;
begin
  POP3.Connect;
  liMessages := POP3.CheckMessages;
  Memo1.Lines.Add('CheckMessages: ' + IntToSTr(liMessages));
  lMsg := TIdMessage.Create;
  try
    POP3.Retrieve(1, lMsg);
    Memo1.Lines.Text := lMsg.MsgId;
    for liCount := 0 to lMsg.MessageParts.Count-1 do
      if lMsg.MessageParts[liCount] is TIdText then
        Memo1.Lines.AddStrings((lMsg.MessageParts[liCount] as TIdText).Body);
  finally
    lMsg.Free;
  end;
end;

end.

//代码结束

//开始DFM

object Form1: TForm1
  Left = 192
  Top = 114
  Width = 696
  Height = 480
  Caption = 'Form1'
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'MS Sans Serif'
  Font.Style = []
  OldCreateOrder = False
  PixelsPerInch = 96
  TextHeight = 13
  object Button1: TButton
    Left = 216
    Top = 16
    Width = 75
    Height = 25
    Caption = 'Button1'
    TabOrder = 0
    OnClick = Button1Click
  end
  object Memo1: TMemo
    Left = 24
    Top = 56
    Width = 657
    Height = 185
    Lines.Strings = (
      'Memo1')
    TabOrder = 1
  end
  object POP3: TIdPOP3
    IOHandler = SSLHandler
    AutoLogin = True
    Host = 'pop.gmail.com'
    Username = 'YourName@gmail.com'
    UseTLS = utUseImplicitTLS
    Password = 'YourPassword'
    Port = 995
    SASLMechanisms = <>
    Left = 40
    Top = 16
  end
  object SSLHandler: TIdSSLIOHandlerSocketOpenSSL
    Destination = 'pop.gmail.com:995'
    Host = 'pop.gmail.com'
    MaxLineAction = maException
    Port = 995
    DefaultPort = 0
    SSLOptions.Method = sslvSSLv3
    SSLOptions.Mode = sslmUnassigned
    SSLOptions.VerifyMode = []
    SSLOptions.VerifyDepth = 0
    Left = 80
    Top = 16
  end
end

//结束DFM

Answer 1

下面的测试代码对我通过 POP3 登录 Gmail 来说效果很好:

procedure Test;
var
  IdPOP3: TIdPOP3;
  IdSSL: TIdSSLIOHandlerSocketOpenSSL;
begin
  IdPOP3 := TIdPOP3.Create(nil);
  try
    IdPOP3.Host := 'pop.gmail.com';
    IdPOP3.Port := 995;
    IdPOP3.Username := MyGmailUsername;
    IdPOP3.Password := MyGmailAppPassword;
    IdPOP3.ConnectTimeout := 60000;

    IdSSL := TIdSSLIOHandlerSocketOpenSSL.Create(IdPOP3);
    IdSSL.SSLOptions.Method := sslvTLSv1;
    IdSSL.SSLOptions.Mode := sslmClient;
    IdPOP3.IOHandler := IdSSL;
    IdPOP3.UseTLS := utUseImplicitTLS;

    IdPOP3.Connect;
    try
      // use IdPOP3 as needed...
    finally
      IdPOP3.Disconnect;
    end;
  finally
    IdPOP3.Free;
  end;
end;

更新

注意:Indy 本身还不支持 OAuth 身份验证(但有 3rd 方实现 float )，因此如果您想使用您的真实密码(而不是使用 3rd 方身份验证)，那么您需要调整您的 Google 帐户安全设置为 allow less secure apps访问您的帐户。但是，如果您有 2-Step Verification在您的帐户中启用(并且您应该)，您不需要允许访问“不太安全的应用程序”，您可以生成一个 application-specific password并使用它代替您的真实密码。