Sponsored Content
Top Forums UNIX for Beginners Questions & Answers Answers to Frequently Asked Questions Email Antispam Techniques and Email Filtering allowing others with dynamic IPs to use your email service. Post 34333 by norsk hedensk on Monday 17th of February 2003 12:26:41 PM
Old 02-17-2003
allowing others with dynamic IPs to use your email service.

if you are running pop3 and smtp and wish to allow others to have an email address using your service out side of your local network you may run into a problem; relaying should be disallowed for others out side of your private network, so how do you allow someone with an account that you gave them to use your mail service, without opening your server to be an open relay for anyone who wants to abuse it? this website: http://popbsmtp.sourceforge.net/

provides a great perl utility that will look at successful pop3 logins and then create a temporary database with that users ipaddress and user name. with that you can set your mail server, (postfix, sendmail...) to look at the database and will allow mail relaying for those that have successful pop3 logins. this utility works with various pop3 servers, and the website includes detailed instructions on just exactly how to set it up. all youll hav eto do i tell your users to CHECK their mail first before they try to send it.
 

6 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

Sql dynamic table / dynamic inserts

I have a file that reads File (X.txt) Contents of record 1: rdrDESTINATION_ADDRESS (String) "91 971502573813" rdrDESTINATION_IMSI (String) "000000000000000" rdrORIGINATING_ADDRESS (String) "d0 movies" rdrORIGINATING_IMSI (String) "000000000000000" rdrTRAFFIC_EVENT_TIME... (0 Replies)
Discussion started by: magedfawzy
0 Replies

2. Shell Programming and Scripting

Dynamic email attachments

Hi all, I am quite new to Unix shell scripting and I am trying to create a common function to send mail that is capable of adding multiple attachments. The script works if there is only one attachment. But when there is more than one, it just won't work. It gives a syntax message "Usage:... (3 Replies)
Discussion started by: dongzky
3 Replies

3. Red Hat

Need help in allowing symmetric cryptography[2]

I have encountered some problems in my school work. Here is the question: The server that provides the time synchronization must be configured to allow its clients to verify its authenticity using symmetric cryptography. Much Appreciated!:) (1 Reply)
Discussion started by: wilsonljx
1 Replies

4. Homework & Coursework Questions

Need help in allowing symmetric cryptography[2]

The server that provides the time synchronization must be configured to allow its clients to verify its authenticity using symmetric cryptography. 4. Singapore Polytechnic, Dover, Singapore,Mr Kam, and Computer Engineering I don't think there is any coding since it is just configuring... (3 Replies)
Discussion started by: wilsonljx
3 Replies

5. Cybersecurity

IP Tables not allowing ports

Hi guys, I'm trying to configure iptables to only allow certain ports access. I set the first set of rules to block everything and then subsequently open ports as needed, but everything still seems to be blocked. I have read that the order matters (new to iptables), perhaps this is an issue.... (6 Replies)
Discussion started by: 3therk1ll
6 Replies

6. UNIX for Dummies Questions & Answers

Allowing External Scans

Hello! I run an HP Unix system which I host oracle databases on, as well as oracle based apps used by my company. My IA department needs to scan my files to ensure I am following IA procedures and check for vulnerabilities in scripts etc. The scan is coming from corporate, and they asked for... (2 Replies)
Discussion started by: hpuxguy
2 Replies
pop3(n) 						      Tcl POP3 Client Library							   pop3(n)

__________________________________________________________________________________________________________________________________________________

NAME
pop3 - Tcl client for POP3 email protocol SYNOPSIS
package require Tcl 8.2 package require pop3 ?1.7? ::pop3::open ?-msex 0|1? ?-retr-mode retr|list|slow? ?-socketcmd cmdprefix? host username password ?port? ::pop3::config chan ::pop3::status chan ::pop3::last chan ::pop3::retrieve chan startIndex ?endIndex? ::pop3::delete chan startIndex ?endIndex? ::pop3::list chan ?msg? ::pop3::top chan msg n ::pop3::uidl chan ?msg? ::pop3::close chan _________________________________________________________________ DESCRIPTION
The pop3 package provides a simple Tcl-only client library for the POP3 email protocol as specified in RFC 1939 [http://www.rfc-edi- tor.org/rfc/rfc1939.txt]. It works by opening the standard POP3 socket on the server, transmitting the username and password, then provid- ing a Tcl API to access the POP3 protocol commands. All server errors are returned as Tcl errors (thrown) which must be caught with the Tcl catch command. API
::pop3::open ?-msex 0|1? ?-retr-mode retr|list|slow? ?-socketcmd cmdprefix? host username password ?port? Open a socket connection to the server specified by host, transmit the username and password as login information to the server. The default port number is 110, which can be overridden using the optional port argument. The return value is a channel used by all of the other ::pop3 functions. The command recognizes three options -msex boolean Setting this option tells the package that the server we are talking to is an MS Exchange server (which has some oddities we have to work around). The default is False. -retr-mode retr|list|slow The retrieval mode determines how exactly messages are read from the server. The allowed values are retr, list and slow. The default is retr. See ::pop3::retrieve for more information. -socketcmd cmdprefix This option allows the user to overide the use of the builtin socket command with any API-compatible command. The envisioned main use is the securing of the new connection via SSL, through the specification of the command tls::socket. This command is specially recognized as well, changing the default port of the connection to 995. ::pop3::config chan Returns the configuration of the pop3 connection identified by the channel handle chan as a serialized array. ::pop3::status chan Query the server for the status of the mail spool. The status is returned as a list containing two elements, the first is the num- ber of email messages on the server and the second is the size (in octets, 8 byte blocks) of the entire mail spool. ::pop3::last chan Query the server for the last email message read from the spool. This value includes all messages read from all clients connecting to the login account. This command may not be supported by the email server, in which case the server may return 0 or an error. ::pop3::retrieve chan startIndex ?endIndex? Retrieve a range of messages from the server. If the endIndex is not specified, only one message will be retrieved. The return value is a list containing each message as a separate element. See the startIndex and endIndex descriptions below. The retrieval mode determines how exactly messages are read from the server. The mode retr assumes that the RETR command delivers the size of the message as part of the command status and uses this to read the message efficiently. In mode list RETR does not deliver the size, but the LIST command does and we use this to retrieve the message size before the actual retrieval, which can then be done efficiently. In the last mode, slow, the system is unable to obtain the size of the message to retrieve in any manner and falls back to reading the message from the server line by line. It should also be noted that the system checks upon the configured mode and falls back to the slower modes if the above assumptions are not true. ::pop3::delete chan startIndex ?endIndex? Delete a range of messages from the server. If the endIndex is not specified, only one message will be deleted. Note, the indices are not reordered on the server, so if you delete message 1, then the first message in the queue is message 2 (message index 1 is no longer valid). See the startIndex and endIndex descriptions below. startIndex The startIndex may be an index of a specific message starting with the index 1, or it have any of the following values: start This is a logical value for the first message in the spool, equivalent to the value 1. next The message immediately following the last message read, see ::pop3::last. end The most recent message in the spool (the end of the spool). This is useful to retrieve only the most recent message. endIndex The endIndex is an optional parameter and defaults to the value "-1", which indicates to only retrieve the one message speci- fied by startIndex. If specified, it may be an index of a specific message starting with the index "1", or it may have any of the following values: last The message is the last message read by a POP3 client, see ::pop3::last. end The most recent message in the spool (the end of the spool). ::pop3::list chan ?msg? Returns the scan listing of the mailbox. If parameter msg is given, then the listing only for that message is returned. ::pop3::top chan msg n Optional POP3 command, not all servers may support this. ::pop3::top retrieves headers of a message, specified by parameter msg, and number of n lines from the message body. ::pop3::uidl chan ?msg? Optional POP3 command, not all servers may support this. ::pop3::uidl returns the uid listing of the mailbox. If the parameter msg is specified, then the listing only for that message is returned. ::pop3::close chan Gracefully close the connect after sending a POP3 QUIT command down the socket. SECURE MAIL TRANSFER
A pop3 connection can be secured with SSL/TLS by requiring the package TLS and then using the option -socketcmd of the command pop3::open to force the use of the tls::socket command when opening the connection. package require tls tls::init -cafile /path/to/ca/cert -keyfile ... # Create secured pop3 channel pop3::open -socketcmd tls::socket \ $thehost $theuser $thepassword ... BUGS, IDEAS, FEEDBACK This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category pop3 of the Tcllib SF Trackers [http://sourceforge.net/tracker/?group_id=12883]. Please also report any ideas for enhancements you may have for either package and/or documentation. KEYWORDS
email, mail, pop, pop3, rfc 1939, secure, ssl, tls CATEGORY
Networking pop3 1.7 pop3(n)
All times are GMT -4. The time now is 08:21 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy