Introduction
Sending email from Windows, Android and iOS Delphi applications over public SMTP servers requires an encrypted connection. Internet Direct (Indy) configuration for SSL/TLS connections is shown in this example source code.
Disclaimer
This code is mostly based on code posted in the Embarcadero forum and here.
Example usage
procedure TFormMailDemo.ButtonSendClick(Sender: TObject); var Mail: TSSLEmail; begin if EditToEmail.Text <> '' then begin Mail := TSSLEmail.Create('mail.example.com', 465, 'me@example.com', '***'); try Mail.edSenderName := 'ABC Inc.'; Mail.edSenderEmail := 'abc@example.com'; Mail.edToEmail := EditToEmail.Text; Mail.edSubject := EditSubject.Text; Mail.edBody := MemoBody.Lines; Mail.SendEmail; EditToEmail.Text:=''; EditSubject.Text:=''; MemoBody.Clear; finally Mail.Free; end; end; end;
Requirements
The code requires Internet Direct (Indy) version 10.6.
Note that the application needs the SSL dynamic link libraries, which can be found at indy.fulgan.com/SSL.
Supported platforms
The code has been tested with Delphi 2009 on Windows. The original code in the linked article reportedly works with Android.
For iOS, please also read this article.
Feedback and support
Feedback is welcome, please visit Habarisoft web page to find contact information. The source code is unsupported example code, use it at your own risk.
Source code
The source code for the SSL mail unit is shown below.
unit IndySecureMailClient; interface uses IdMessage, Classes, IdSMTP; const SMTP_PORT_EXPLICIT_TLS = 587; type TSSLEmail = class(TObject) private IdMessage: TIdMessage; SMTP: TIdSMTP; FedBody: TStrings; FedSMTPPort: Integer; FedToEmail: string; FedSubject: string; FedSMTPServer: string; FedCCEmail: string; FedPassword: string; FedBCCEmail: string; FedSenderName: string; FedUserName: string; FedPriority: TIdMessagePriority; FedSenderEmail: string; FedSSLConnection: Boolean; // Getter / Setter procedure SetBody(const Value: TStrings); procedure Init; procedure InitMailMessage; procedure InitSASL; procedure AddSSLHandler; public constructor Create; overload; constructor Create(const ASMTPServer: string; const ASMTPPort: Integer; const AUserName, APassword: string); overload; destructor Destroy; override; procedure SendEmail; // Properties property edBCCEmail: string read FedBCCEmail write FedBCCEmail; property edBody: TStrings read FedBody write SetBody; property edCCEmail: string read FedCCEmail write FedCCEmail; property edPassword: string read FedPassword write FedPassword; property edPriority: TIdMessagePriority read FedPriority write FedPriority; property edSenderEmail: string read FedSenderEmail write FedSenderEmail; property edSenderName: string read FedSenderName write FedSenderName; property edSMTPServer: string read FedSMTPServer write FedSMTPServer; property edSMTPPort: Integer read FedSMTPPort write FedSMTPPort; property edSSLConnection: Boolean read FedSSLConnection write FedSSLConnection; property edToEmail: string read FedToEmail write FedToEmail; property edUserName: string read FedUserName write FedUserName; property edSubject: string read FedSubject write FedSubject; end; implementation uses IdComponent, IdTCPConnection, IdTCPClient, IdExplicitTLSClientServerBase, IdMessageClient, IdSMTPBase, IdBaseComponent, IdIOHandler, IdIOHandlerSocket, IdIOHandlerStack, IdSSL, IdSSLOpenSSL, IdSASLLogin, IdSASL_CRAM_SHA1, IdSASL, IdSASLUserPass, IdSASL_CRAMBase, IdSASL_CRAM_MD5, IdSASLSKey, IdSASLPlain, IdSASLOTP, IdSASLExternal, IdSASLDigest, IdSASLAnonymous, IdUserPassProvider; constructor TSSLEmail.Create; begin inherited; Init; FedBody := TStringList.Create; end; procedure TSSLEmail.Init; begin edSSLConnection := True; edPriority := TIdMessagePriority.mpNormal; end; constructor TSSLEmail.Create(const ASMTPServer: string; const ASMTPPort: Integer; const AUserName, APassword: string); begin Create; edSMTPServer := ASMTPServer; edSMTPPort := ASMTPPort; edUserName := AUserName; edPassword := APassword; end; destructor TSSLEmail.Destroy; begin edBody.Free; inherited; end; // Setter / Getter ----------------------------------------------------------- procedure TSSLEmail.SetBody(const Value: TStrings); begin FedBody.Assign(Value); end; // Send the mail ------------------------------------------------------------- procedure TSSLEmail.SendEmail; begin IdMessage := TIdMessage.Create; try InitMailMessage; SMTP := TIdSMTP.Create; try if edSSLConnection then begin AddSSLHandler; if edSMTPPort = SMTP_PORT_EXPLICIT_TLS then SMTP.UseTLS := utUseExplicitTLS else SMTP.UseTLS := utUseImplicitTLS; end; if (edUserName<>'') or (edPassword<>'') then begin SMTP.AuthType := satSASL; InitSASL; end else begin SMTP.AuthType := satNone; end; SMTP.Host := edSMTPServer; SMTP.Port := edSMTPPort; SMTP.ConnectTimeout := 30000; SMTP.UseEHLO := True; SMTP.Connect; try SMTP.Send(IdMessage); finally SMTP.Disconnect; end; finally SMTP.Free; end; finally IdMessage.Free; end; end; // Prepare the mail ---------------------------------------------------------- procedure TSSLEmail.InitMailMessage; begin IdMessage.ContentType := 'text/plain'; IdMessage.Charset := 'UTF-8'; IdMessage.Body := edBody; IdMessage.Sender.Text := edSenderEMail; IdMessage.From.Name := edSenderName; IdMessage.From.Address := edSenderEMail; IdMessage.ReplyTo.EMailAddresses := edSenderEmail; IdMessage.Recipients.EMailAddresses := edToEmail; IdMessage.Subject := edSubject; IdMessage.Priority := edPriority; IdMessage.CCList.EMailAddresses := edCCEMail; IdMessage.ReceiptRecipient.Text := ''; IdMessage.BccList.EMailAddresses := edBCCEMail; end; procedure TSSLEmail.AddSSLHandler; var SSLHandler: TIdSSLIOHandlerSocketOpenSSL; begin SSLHandler := TIdSSLIOHandlerSocketOpenSSL.Create(SMTP); // SSL/TLS handshake determines the highest available SSL/TLS version dynamically SSLHandler.SSLOptions.Method := sslvSSLv23; SSLHandler.SSLOptions.Mode := sslmClient; SSLHandler.SSLOptions.VerifyMode := []; SSLHandler.SSLOptions.VerifyDepth := 0; SMTP.IOHandler := SSLHandler; end; procedure TSSLEmail.InitSASL; var IdUserPassProvider: TIdUserPassProvider; IdSASLCRAMMD5: TIdSASLCRAMMD5; IdSASLCRAMSHA1: TIdSASLCRAMSHA1; IdSASLPlain: TIdSASLPlain; IdSASLLogin: TIdSASLLogin; IdSASLSKey: TIdSASLSKey; IdSASLOTP: TIdSASLOTP; IdSASLAnonymous: TIdSASLAnonymous; IdSASLExternal: TIdSASLExternal; begin IdUserPassProvider := TIdUserPassProvider.Create(SMTP); IdUserPassProvider.Username := edUserName; IdUserPassProvider.Password:= edPassword; IdSASLCRAMSHA1 := TIdSASLCRAMSHA1.Create(SMTP); IdSASLCRAMSHA1.UserPassProvider := IdUserPassProvider; IdSASLCRAMMD5 := TIdSASLCRAMMD5.Create(SMTP); IdSASLCRAMMD5.UserPassProvider := IdUserPassProvider; IdSASLSKey := TIdSASLSKey.Create(SMTP); IdSASLSKey.UserPassProvider := IdUserPassProvider; IdSASLOTP := TIdSASLOTP.Create(SMTP); IdSASLOTP.UserPassProvider := IdUserPassProvider; IdSASLAnonymous := TIdSASLAnonymous.Create(SMTP); IdSASLExternal := TIdSASLExternal.Create(SMTP); IdSASLLogin := TIdSASLLogin.Create(SMTP); IdSASLLogin.UserPassProvider := IdUserPassProvider; IdSASLPlain := TIdSASLPlain.Create(SMTP); IdSASLPlain.UserPassProvider := IdUserPassProvider; SMTP.SASLMechanisms.Add.SASL := IdSASLCRAMSHA1; SMTP.SASLMechanisms.Add.SASL := IdSASLCRAMMD5; SMTP.SASLMechanisms.Add.SASL := IdSASLSKey; SMTP.SASLMechanisms.Add.SASL := IdSASLOTP; SMTP.SASLMechanisms.Add.SASL := IdSASLAnonymous; SMTP.SASLMechanisms.Add.SASL := IdSASLExternal; SMTP.SASLMechanisms.Add.SASL := IdSASLLogin; SMTP.SASLMechanisms.Add.SASL := IdSASLPlain; end; end.