Pascal (Lazarus/Delphi)

IMAP Download and Verify Signed (S/MIME) Email

See more IMAP Examples

Demonstrates how to download and verify digitally signed S/MIME email. Pascal (Lazarus/Delphi)

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.Imap,
  Chilkat.Cert,
  Chilkat.Email,
  Chilkat.MessageSet;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  imap: TImap;
  fetchUids: Boolean;
  messageSet: TMessageSet;
  email: TEmail;
  cert: TCert;
  i: Integer;
  uid: string;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  imap := TImap.Create;

  //  Connect to an IMAP server.
  //  Use TLS
  imap.Ssl := True;
  imap.Port := 993;
  success := imap.Connect('imap.example.com');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  success := imap.Login('myLogin','myPassword');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  //  Select an IMAP mailbox
  success := imap.SelectMailbox('Inbox');
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  //  We can choose to fetch UIDs or sequence numbers.
  fetchUids := True;

  //  Get the message IDs of all the emails in the mailbox
  messageSet := TMessageSet.Create;
  success := imap.QueryMbx('ALL',fetchUids,messageSet);
  if (success = False) then
    begin
      WriteLn(imap.LastErrorText);
      Exit;
    end;

  email := TEmail.Create;
  cert := TCert.Create;

  i := 0;
  while i < messageSet.Count do
    begin

      uid := messageSet.GetId(i);
      WriteLn('uid: ' + uid);

      success := imap.FetchEmail(False,uid,True,email);
      if (success = False) then
        begin
          WriteLn(imap.LastErrorText);
          Exit;
        end;

      //  The security layers of signed and/or encrypted emails
      //  are automatically "unwrapped" when loaded into
      //  a Chilkat email object.
      //  An application only needs to check to see if an email
      //  was received signed or encrypted, and then examine
      //  the success/failure.  For example:
      if (email.ReceivedSigned = True) then
        begin

          WriteLn('This email was signed.');

          //  Check to see if the signatures were verified.
          if (email.SignaturesValid = True) then
            begin
              WriteLn('Digital signature(s) verified.');
              WriteLn('Signer: ' + email.SignedBy);

              //  Get the certificate used for signing.
              success := email.LastSignerCert(0,cert);

              if (success = False) then
                begin
                  WriteLn('Failed to get signing certificate object.');
                end
              else
                begin
                  WriteLn('Signing cert: ' + cert.SubjectCN);
                end;

            end
          else
            begin
              WriteLn('Digital signature verification failed.');
            end;

        end;

      i := i + 1;
    end;

  //  Disconnect from the IMAP server.
  success := imap.Disconnect();


  imap.Free;
  messageSet.Free;
  email.Free;
  cert.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.