Decrypts the encrypted email by digital certificate.
[Visual Basic 6.0]
Public Function Decrypt( _
Cert As Certitifcate _
) As Mail
[Visual C++]
public: HRESULT Decrypt(
ICertitifcate * Cert,
IMail** pVal
);
Parameters
Return Value
Example
[Visual Basic 6.0, VBScript, Visual C++, Delphi] The following example demonstrates how to verify signed email and decrypt encrypted email with EAGetMail POP3 & IMAP4 Component. To get the full samples of EAGetMail, please refer to Samples section.
[Visual Basic 6.0]
Const CRYPT_MACHINE_KEYSET = 32
Const CRYPT_USER_KEYSET = 4096
Const CERT_SYSTEM_STORE_CURRENT_USER = 65536
Const CERT_SYSTEM_STORE_LOCAL_MACHINE = 131072
Sub VerifyAndDecryptEmail()
On Error Resume Next
Dim oMail As New EAGetMailObjLib.Mail
oMail.LicenseCode = "TryIt"
oMail.LoadFile "c:\test.eml", False
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
If (oMail.IsEncrypted) Then
' this email is encrypted, we decrypt it by user default certificate.
' you can also use specified certificate like this
' Dim oCert As New EAGetMailObjLib.Certificate
' oCert.LoadFromFile "c:\test.pfx", "pfxpassword", CRYPT_USER_KEYSET
' Set oMail = oMail.Decrypt(oCert)
Set oMail = oMail.Decrypt(Nothing)
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
End If
If (oMail.IsSigned) Then
'this email is digital signed.
Dim oCert As EAGetMailObjLib.Certificate
Set oCert = oMail.VerifySignature()
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
MsgBox "This email contains a valid digital signature."
'you can add the certificate to your certificate storage like this
'oCert.AddToStore CERT_SYSTEM_STORE_CURRENT_USER,"addressbook"
'then you can use send the encrypted email back to this sender.
End If
End Sub
[VBScript]
Const CRYPT_MACHINE_KEYSET = 32
Const CRYPT_USER_KEYSET = 4096
Const CERT_SYSTEM_STORE_CURRENT_USER = 65536
Const CERT_SYSTEM_STORE_LOCAL_MACHINE = 131072
On Error Resume Next
Dim oMail
Set oMail = CreateObject("EAGetMailObj.Mail")
oMail.LicenseCode = "TryIt"
oMail.LoadFile "c:\test.eml", False
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
If (oMail.IsEncrypted) Then
' this email is encrypted, we decrypt it by user default certificate.
' you can also use specified certificate like this
' Dim oCert
' Set oCert = CreateObject("EAGetMailObj.Certificate")
' oCert.LoadFromFile "c:\test.pfx", "pfxpassword", CRYPT_USER_KEYSET
' Set oMail = oMail.Decrypt(oCert)
Set oMail = oMail.Decrypt(Nothing)
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
End If
If (oMail.IsSigned) Then
'this email is digital signed.
Dim oCert
Set oCert = oMail.VerifySignature()
If Err.Number <> 0 Then
MsgBox Err.Description
Exit Sub
End If
MsgBox "This email contains a valid digital signature."
'you can add the certificate to your certificate storage like this
'oCert.AddToStore CERT_SYSTEM_STORE_CURRENT_USER,"addressbook"
'then you can use send the encrypted email back to this sender.
End If
[Visual C++]
#include "stdafx.h"
#include <windows.h>
#include "eagetmailobj.tlh"
using namespace EAGetMailObjLib;
vod VerifyAndDecryptEmail()
{
::CoInitialize(NULL);
try
{
IMailPtr oMail = NULL;
oMail.CreateInstance(__uuidof(EAGetMailObjLib::Mail));
oMail->LicenseCode = _T("TryIt");
oMail->LoadFile(_T("d:\\test.eml"), VARIANT_FALSE);
if(oMail->IsEncrypted == VARIANT_TRUE)
{
//this email is encrypted, we decrypt it by user default certificate.
// you can also use specified certificate like this
//ICertificatePtr oCert;
//oCert.CreateInstance(__uuidof(EAGetMailObjLib::Certificate));
//oCert->LoadFromFile(_T("c:\\test.pfx"), _T("pfxpassword"), CRYPT_USER_KEYSET);
//oMail = oMail->Decrypt(oCert);
oMail = oMail->Decrypt(NULL);
}
if(oMail->IsSigned == VARIANT_TRUE)
{
ICertificatePtr oCert = oMail->VerifySignature();
MessageBox(NULL, _T("This email contains a valid digital signature."), NULL, MB_OK);
//you can add the certificate to your certificate storage like this
//oCert->AddToStore(CERT_SYSTEM_STORE_CURRENT_USER, _T("addressbook"));
// then you can use send the encrypted email back to this sender.
}
}
catch(_com_error &ep)
{
MessageBox(NULL, (TCHAR*)ep.Description(), NULL, MB_OK);
}
::CoUninitialize();
}
[Delphi]
const
CRYPT_MACHINE_KEYSET = 32;
CRYPT_USER_KEYSET = 4096;
CERT_SYSTEM_STORE_CURRENT_USER = 65536;
CERT_SYSTEM_STORE_LOCAL_MACHINE = 131072;
procedure VerifyAndDecryptEmail();
Var
oMail: TMail;
oCert: TCertificate;
oSignerCert: ICertificate;
begin
oMail := TMail.Create(Application);
oMail.LicenseCode := 'TryIt';
oMail.LoadFile('d:\test.eml', false);
if oMail.IsEncrypted then
try
// this email is encrypted, decrypt it by default user certificate
oMail.ConnectTo(oMail.Decrypt(nil));
// You can also use specified certificate like this
// oCert := TCertificate.Create(Application);
// oCert.LoadFromFile('c:\test.pfx', 'pfxpassword', CRYPT_USER_KEYSET);
// oMail.Load(oMail.Decrypt(oCert.DefaultInterface).Content);
except
on ep: exception do
ShowMessage('Decrypt Error: ' + ep.Message);
end;
if oMail.IsSigned then
try
// this email is digital signed, verify signature
oSignerCert := oMail.VerifySignature();
ShowMessage('This email contains a valid digital signature.');
// You can add the certificate to your certificate storage like this
// oSignerCert.AddToStore(CERT_SYSTEM_STORE_CURRENT_USER,
// 'addressbook');
// Then you can use send the encrypted email back to this sender.
except
on ep: Exception do
ShowMessage('Verify signature Error: ' + ep.Message);
end;
end;
Remarks
See Also
Mail.IsSigned Property
Mail.VerifySignature Method
Mail.IsEncrypted Property
Online Tutorials
Verify Digital Signature and Decrypt Email in VB6 - Tutorial
Verify Digital Signature and Decrypt Email in Delphi - Tutorial
Verify Digital Signature and Decrypt Email in VC++ - Tutorial