wodPop3Server ActiveX Control - Command Method
 Command Method
      
 

Description

Called when user issues new command.


Return Type

None  


Syntax

object.Command Owner, User, Command



The Command Method syntax has these parts:

Part Description
object An expression evaluating to an object of type wodPop3Notify.
Owner  A wodPop3ServerCom object. Reference to wodPop3ServerCom instance that called this callback method.
User  A Pop3User object. Reference to user sent the command.
Command  A String value. Command that was executed, together with any parameters after it.

Remarks

NOTE: This method is called only if you implemented IwodPop3Notify interface in your application, and wodPop3Server1.Notification property has received reference to instance of your implementation.

This notification method will be called each time user issues some command, no matter what user's state is set to. For instance, after Connecting notification you will not receive any additional events until user sends username/password combination. However, if you're interested if he's testing your server for some other commands or vulnerabilities, you can just track down every command he sends using this property.

You should understand that this notification method is in the middle of the chain between user's command and wodPop3Server's processor. This means that before wodPop3Server receives this command and examine it, you will receive this notification where you can change Command argument. Changing this argument will directly affect wodPop3Server's behaviour. For instance, if user sends command 'USER test' you can do

Command = "USER joe"

and then after it user sends 'PASS test' and you change it to

Command = "PASS joe"

Do you have idea what will happen? wodPop3Server will receive username/password combination as you changed it, so it will try to login user joe/joe instead of (for example) test/test. Later you can change any particular command like this.

If you don't like how wodPop3Server reacts on specific command, you can implement it yourself different way. For instance, if you want 'TOP' command NOT to work, you can just do something like this:

If Ucase$(Left$(Command, 3)) = "TOP" Then
   Command = ""
   User.Send "-ERR command unrecognized" & vbCrLf
End If

This way wodPop3Server will just ignore command because Command is set to empty string, and you already sent some reply, so no protocol violations are made.

More, if you want to implement new command, for instance 'HELP' command you should do same as above - test if command is entered, set Command argument to empty string, and Send some response manually using POP3 protocol specification.