/// <summary>
/// Filters message.
/// </summary>
/// <param name="messageStream">Message stream which to filter.</param>
/// <param name="filteredStream">Filtered stream.</param>
/// <param name="sender">Senders email address.</param>
/// <param name="recipients">Recipients email addresses.</param>
/// <param name="api">Access to server API.</param>
/// <param name="session">Reference to SMTP session.</param>
/// <param name="errorText">Filtering error text what is returned to client. ASCII text, 500 chars maximum.</param>
public FilterResult Filter(Stream messageStream, out Stream filteredStream, string sender, string[] recipients, IMailServerApi api, SMTP_Session session, out string errorText)
{
errorText = null;
filteredStream = null;
try{
// Store message to tmp file
string file = API_Utlis.PathFix(Path.GetTempPath() + "\\" + Guid.NewGuid().ToString() + ".eml");
using (FileStream fs = File.Create(file)){
byte[] data = new byte[messageStream.Length];
messageStream.Read(data, 0, data.Length);
fs.Write(data, 0, data.Length);
}
// Execute virus program to scan tmp message
// #FileName - place holder is replaced with file
DataSet ds = new DataSet();
ds.Tables.Add("Settings");
ds.Tables["Settings"].Columns.Add("Program");
ds.Tables["Settings"].Columns.Add("Arguments");
ds.Tables["Settings"].Columns.Add("VirusExitCode");
ds.ReadXml(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) + "\\lsVirusFilter_db.xml");
string virusSoft = ds.Tables["Settings"].Rows[0]["Program"].ToString();
string virusSoftArgs = ds.Tables["Settings"].Rows[0]["Arguments"].ToString().Replace("#FileName", file);
int virusExitCode = ConvertEx.ToInt32(ds.Tables["Settings"].Rows[0]["Program"], 1);
int exitCode = 0;
System.Diagnostics.ProcessStartInfo sInf = new System.Diagnostics.ProcessStartInfo(virusSoft, virusSoftArgs);
sInf.CreateNoWindow = true;
sInf.UseShellExecute = false;
System.Diagnostics.Process p = System.Diagnostics.Process.Start(sInf);
if (p != null)
{
p.WaitForExit(60000);
exitCode = p.ExitCode;
}
if (File.Exists(file))
{
// Return scanned message and delete tmp file
using (FileStream fs = File.OpenRead(file)){
byte[] data = new byte[fs.Length];
fs.Read(data, 0, data.Length);
filteredStream = new MemoryStream(data);
}
File.Delete(file);
}
// Virus scanner deleted messaeg, probably contains virus
else
{
virusExitCode = exitCode;
}
// Do exit code mapping
if (virusExitCode == exitCode)
{
errorText = "Message is blocked, contains virus !";
return(FilterResult.Error);
}
}
catch (Exception x) {
string dummy = x.Message;
// Virus scanning failed, allow message through
filteredStream = messageStream;
}
return(FilterResult.Store);
}
