private Boolean FilterCallback(IntPtr sendDataPtr, IntPtr replyDataPtr)
{
bool retVal = true;
try
{
FilterAPI.MessageSendData messageSend = new FilterAPI.MessageSendData();
messageSend = (FilterAPI.MessageSendData)Marshal.PtrToStructure(sendDataPtr, typeof(FilterAPI.MessageSendData));
if (FilterAPI.MESSAGE_SEND_VERIFICATION_NUMBER != messageSend.VerificationNumber)
{
EventManager.WriteMessage(139, "FilterCallback", EventLevel.Error, "Received message corrupted.Please check if the MessageSendData structure is correct.");
return(false);
}
if (messageSend.MessageType == (uint)FilterAPI.FilterCommand.FILTER_REQUEST_ENCRYPTION_IV_AND_KEY)
{
if ((replyDataPtr.ToInt64() != 0))
{
//this is the customized tag data which was attahced to the encrypted file when it was created.
uint tagDataLength = messageSend.DataBufferLength;
byte[] tagData = messageSend.DataBuffer;
FilterAPI.MessageReplyData messageReply = (FilterAPI.MessageReplyData)Marshal.PtrToStructure(replyDataPtr, typeof(FilterAPI.MessageReplyData));
messageReply.MessageId = messageSend.MessageId;
messageReply.MessageType = messageSend.MessageType;
//get permission for secure shared file from server, here just demo the server in local,
//in reality, your server could be in remote computer.
retVal = DRServer.GetFileAccessPermission(ref messageSend, ref messageReply);
if (retVal)
{
messageReply.ReturnStatus = (uint)FilterAPI.NTSTATUS.STATUS_SUCCESS;
}
else
{
//if you don't want to authorize the process to read the encrytped file,you can set the value as below:
messageReply.ReturnStatus = (uint)FilterAPI.NTSTATUS.STATUS_ACCESS_DENIED;
messageReply.FilterStatus = (uint)FilterAPI.FilterStatus.FILTER_COMPLETE_PRE_OPERATION;
}
Marshal.StructureToPtr(messageReply, replyDataPtr, true);
if (!retVal)
{
messageSend.Status = (uint)FilterAPI.NTSTATUS.STATUS_ACCESS_DENIED;
}
}
}
filterMessage.AddMessage(messageSend);
}
catch (Exception ex)
{
EventManager.WriteMessage(134, "FilterCallback", EventLevel.Error, "filter callback exception." + ex.Message);
return(false);
}
return(retVal);
}
private bool CreateOrModifyShareEncryptFile()
{
string lastError = string.Empty;
string authorizedProcessNames = textBox_authorizedProcessNames.Text.Trim();
string unauthorizedProcessNames = textBox_UnauthorizedProcessNames.Text.Trim();
string authorizedUserNames = textBox_AuthorizedUserNames.Text.Trim();
string unauthorizedUserNames = textBox_UnauthorizedUserNames.Text.Trim();
string fileName = textBox_FileName.Text.Trim();
string targetFileName = textBox_TargetName.Text;
try
{
if (fileName.Length == 0)
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("The file name can't be empty.", "Create share encrypted file", MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
DateTime expireDateTime = dateTimePicker_ExpireDate.Value.Date + dateTimePicker_ExpireTime.Value.TimeOfDay;
if (expireDateTime <= DateTime.Now)
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("The expire time can't be less than current time.", "Create share encrypted file", MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
if (selectedDRPolicy != null)
{
DRPolicy drPolicy = GetDRSetting();
string encryptedDRPolicy = DigitalRightControl.EncryptObjectToStr <DRPolicy>(drPolicy);
if (WebAPIServices.ModifySharedFileDRInfo(encryptedDRPolicy, ref lastError))
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("Modify shared file " + textBox_FileName.Text + " policy succeeded.", "Modify shared file", MessageBoxButtons.OK, MessageBoxIcon.Information);
return(true);
}
else
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("Modify shared file " + textBox_FileName.Text + " policy failed with error:" + lastError, "Modify shared file", MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
}
//here we generate the random unique IV and key, you can use your own key and iv
byte[] encryptionIV = Utils.GetRandomIV();
byte[] encryptionKey = Utils.GetRandomKey();
string keyStr = string.Empty;
string ivStr = string.Empty;
if (GlobalConfig.StoreSharedFileMetaDataInServer)
{
long creationTime = DateTime.Now.ToFileTime();
//send the encrypted file digital right information to the server and get back the iv and key.
if (!AddNewFileDRInfoToServer(ref ivStr, ref keyStr, ref creationTime))
{
return(false);
}
if (ivStr.Length > 0 && keyStr.Length > 0)
{
encryptionIV = Utils.ConvertHexStrToByteArray(ivStr);
encryptionKey = Utils.ConvertHexStrToByteArray(keyStr);
}
}
//for this example, we add the encryptIV and account name as the tag data to the encrypted file
//you can add your own custom tag data to the encyrpted file, so when someone open the encrypted file, you will get the tag data.
string tagStr = GlobalConfig.AccountName + ";" + ivStr;
byte[] tagData = UnicodeEncoding.Unicode.GetBytes(tagStr);
bool retVal = false;
if (fileName.Equals(targetFileName, StringComparison.CurrentCulture))
{
retVal = FilterAPI.AESEncryptFileWithTag(fileName, (uint)encryptionKey.Length, encryptionKey, (uint)encryptionIV.Length, encryptionIV, (uint)tagData.Length, tagData);
}
else
{
retVal = FilterAPI.AESEncryptFileToFileWithTag(fileName, targetFileName, (uint)encryptionKey.Length, encryptionKey, (uint)encryptionIV.Length, encryptionIV, (uint)tagData.Length, tagData);
}
if (!retVal)
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("Create encrypted file " + targetFileName + " failed with error:" + FilterAPI.GetLastErrorMessage(), "Create share encrypted file", MessageBoxButtons.OK, MessageBoxIcon.Error);
if (GlobalConfig.StoreSharedFileMetaDataInServer)
{
WebAPIServices.DeleteShareFile(ivStr, ref lastError);
}
if (!fileName.Equals(targetFileName, StringComparison.CurrentCulture))
{
File.Delete(targetFileName);
}
return(false);
}
else
{
//set this flag to the encrypted file, require to get permission from user mode when the file open
if (!FilterAPI.SetHeaderFlags(targetFileName, (uint)AESFlags.Flags_Request_IV_And_Key_From_User, FilterAPI.ALLOW_MAX_RIGHT_ACCESS))
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("SetHeaderFlags for file " + targetFileName + " failed with error:" + FilterAPI.GetLastErrorMessage(), "SetHeaderFlags", MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
if (!GlobalConfig.StoreSharedFileMetaDataInServer)
{
//add the permission meta data to a file and store it in the server, it will be used when the file open.
if (!DRServer.AddDRInfoToFile(targetFileName, authorizedProcessNames, unauthorizedProcessNames, authorizedUserNames, unauthorizedUserNames
, expireDateTime, encryptionIV, encryptionKey, FilterAPI.ALLOW_MAX_RIGHT_ACCESS.ToString()))
{
return(false);
}
}
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
string message = "Create encrypted file " + targetFileName + " succeeded, you can distribute this encrypted file to your client.\r\n\r\nDownload this file to the share file drop folder in the client,";
message += " then start the filter service there, now you can open the encrypted file if the process in client has the permission.";
MessageBox.Show(message, "Share encrypted file", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
return(true);
}
catch (Exception ex)
{
MessageBoxHelper.PrepToCenterMessageBoxOnForm(this);
MessageBox.Show("Create share file failed with error " + ex.Message, "Create share encrypted file", MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
}
