pop3d -
Tcl POP3 server implementation
package require Tcl 8.3
package require pop3d ? 1.1.0 ?
::pop3d::new ? serverName ?
serverName option ? arg arg ... ?
serverName up
serverName down
serverName destroy ? mode ?
serverName configure
serverName configure -option
serverName configure -option value...
serverName cget -option
serverName conn list
serverName conn state id
authCmd exists name
authCmd lookup name
storageCmd dele mbox msgList
storageCmd lock mbox
storageCmd unlock mbox
storageCmd size mbox ? msgId ?
storageCmd stat mbox
storageCmd get mbox msgId
-
::pop3d::new ? serverName ?
-
This command creates a new server object with an associated global Tcl
command whose name is serverName.
The command
serverName may be used to invoke various operations
on the server. It has the following general form:
-
serverName option ? arg arg ... ?
-
Option and the args determine the exact behavior of the
command.
A pop3 server can be started on any port the caller has permission for
from the operating system. The default port will be 110, which is the
port defined by the standard specified in
RFC 1939 (http://www.rfc-editor.org/rfc/rfc1939.txt).
After creating, configuring and starting a the server object will
listen for and accept connections on that port and handle them
according to the POP3 protocol.
Note: The server provided by this module will handle only the
basic protocol by itself. For the higher levels of user authentication
and handling of the actual mailbox contents callbacks will be invoked.
The following commands are possible for server objects:
-
serverName up
-
After this call the server will listen for connections on its configured port.
-
serverName down
-
After this call the server will stop listening for connections. This
does not affect existing connections.
-
serverName destroy ? mode ?
-
Destroys the server object. Currently open connections are handled
depending on the chosen mode.
The provided modes are:
- kill
-
Destroys the server immediately, and forcefully closes all currently
open connections. This is the default mode.
- defer
-
Stops the server from accepting new connections and will actually
destroy it only after the last of the currently open connections for
the server is closed.
-
serverName configure
-
Returns a list containing all options and their current values in a
format suitable for use by the command array set. The options
themselves are described in section Options.
-
serverName configure -option
-
Returns the current value of the specified option. This is an alias
for the method cget. The options themselves are described in
section Options.
-
serverName configure -option value...
-
Sets the specified option to the provided value. The options
themselves are described in section Options.
-
serverName cget -option
-
Returns the current value of the specified option. The options
themselves are described in section Options.
-
serverName conn list
-
Returns a list containing the ids of all connections currently open.
-
serverName conn state id
-
Returns a list suitable for [array set] containing the
state of the connection referenced by id.
The following options are available to pop3 server objects.
-
-port port
-
Defines the port to listen on for new connections. Default is
110. This option is a bit special. If port is set to "0" the
server, or rather the operating system, will select a free port on its
own. When querying -port the id of this chosen port will be
returned. Changing the port while the server is up will neither change
the returned value, nor will it change on which port the server is
listening on. Only after resetting the server via a call to
down followed by a call to up will the new port take
effect. It is at that time that the value returned when querying
-port will change too.
-
-auth command
-
Defines a command prefix to call whenever the authentication of
a user is required. If no such command is specified the server will
reject all users. The interface which has to be provided by the
command prefix is described in section Authentication.
-
-storage command
-
Defines a command prefix to call whenever the handling of
mailbox contents is required. If no such command is specified the
server will claim that all mailboxes are empty. The interface which
has to be provided by the command prefix is described in section
Mailboxes.
-
-socket command
-
Defines a command prefix to call for opening the listening socket.
This can be used to make the pop3 server listen on a SSL socket
as provided by the tls package, see the command tls::socket.
Here we describe the interface which has to be provided by the
authentication callback so that pop3 servers following the interface
of this module are able to use it.
-
authCmd exists name
-
This method is given a username and has to return a boolean
value telling whether or not the specified user exists.
-
authCmd lookup name
-
This method is given a username and has to return a two-element
list containing the password for this user and a storage reference, in
this order.
The storage reference is passed unchanged to the storage callback, see
sections Options and Mailboxes for either the
option defining it and or the interface to provide, respectively.
Here we describe the interface which has to be provided by the storage
callback so that pop3 servers following the interface of this module
are able to use it. The
mbox argument is the storage reference
as returned by the
lookup method of the authentication
command, see section
Authentication.
-
storageCmd dele mbox msgList
- ]
Deletes the messages whose numeric ids are contained in the
msgList from the mailbox specified via mbox.
-
storageCmd lock mbox
-
This method locks the specified mailbox for use by a single connection
to the server. This is necessary to prevent havoc if several
connections to the same mailbox are open. The complementary method is
unlock. The command will return true if the lock could be set
successfully or false if not.
-
storageCmd unlock mbox
-
This is the complementary method to lock, it revokes the lock
on the specified mailbox.
-
storageCmd size mbox ? msgId ?
-
Determines the size of the message specified through its id in
msgId, in bytes, and returns this number. The command will
return the size of the whole maildrop if no message id was specified.
-
storageCmd stat mbox
-
Determines the number of messages in the specified mailbox and returns
this number.
-
storageCmd get mbox msgId
-
Returns a handle for the specified message. This handle is a mime
token following the interface described in the documentation of
package mime. The pop3 server will use the functionality of
the mime token to send the mail to the requestor at the other end of a
pop3 connection.
The option
-socket (see
Options) enables users of
the package to override how the server opens its listening socket.
The envisioned main use is the specification of the
tls::socket
command, see package
tls, to secure the communication.
package require tls
tls::init \\
...
pop3d::new S -socket tls::socket
...
This document, and the package it describes, will undoubtedly contain
bugs and other problems.
Please report such in the category
pop3d of the
http://sourceforge.net/tracker/?group_id=12883.
Please also report any ideas for enhancements you may have for either
package and/or documentation.
pop3, internet, network, protocol, rfc 1939, ssl, tls, secure