Dspam-fork is a project mainly written in C and C++, based on the View license.
fork of dspam project
DSPAM v3.9.1 Copyright (c) 2002-2010 DSPAM Project http://dspam.sourceforge.net/
LICENSE
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
CREDITS
Original Work By Lead development till 3.8.0: Jonathan A. Zdziarski [email protected] Lead development after 3.8.0: Stevan Bajic [email protected] PostgreSQL driver: Rustam Aliyev [email protected] External Lookup module: Hugo Monteiro [email protected] Various: Feb/2006 Cove Schneider [email protected] Jan/2006 Norman Maurer [email protected]
Your name is missing? Let us know with a reference to your commit, and we'll add you to the list.
COPYRIGHT
As of 12 January 2009 the copyright is owned by the DSPAM Project, represented by a team of people, including: Alexander Prinsier Dov Zamir Hugo Monteiro Ion-Mihai Tetcu Paul Cockings Stevan Bajic
TABLE OF CONTENTS
General DSPAM Information
1.0 About DSPAM 1.1 Installation and Configuration 1.2 Testing 1.3 Troubleshooting 1.4 DSPAM Tools 1.5 Agent Commandline Arguments
Advanced DSPAM functionality
2.0 Linking with libdspam 2.1 Configuring groups 2.2 External Inoculation Theory 2.3 Client/Server Mode 2.4 LMTP 2.5 DSPAM User Preferences 2.6 Fallback Domains 2.7 External User Lookup
Miscellaneous
3.0 Bugs, Feature Requests 3.1 Ports / Packages 3.2 GIT Access
1.0 ABOUT DSPAM
DSPAM is an open-source, freely available anti-spam solution designed to combat unsolicited commercial email using advanced statistical analysis. In short, DSPAM filters spam by learning what spam is and isn't. It does this by learning each user's individual mail behavior. This allows DSPAM to provide highly-accurate, personalized filtering for each user on even a large system and provides an administratively maintenance free solution capable of learning each user's email behaviors with very few false positives.
While DSPAM is focused around spam filtering, many have found alternative uses for all types of two-concept document classification.
DSPAM is rapidly gaining a large support forum and being used in many large- scale implementations. Contributions to the project are welcome via the dspam-dev mailing list or in the form of financial contributions.
Many of the foundational principles incorporated into this software were contributed by Paul Graham's white paper on combatting spam, which can be found at http://paulgraham.com/spam.html. Much research and development has resulted in many new approaches being added onto the DPSAM project as well, some of which are explained in white papers on the DSPAM home page.
DSPAM can be implemented as a total solution, or as a library which developers may link their projects to the dspam core engine (libdspam) in accordance with the GPL license agreement. This enables developers to incorporate libdspam as a "drop-in" for instant spam filtering within their applications - such as mail clients, other anti-spam tools, and so on.
PLEASE NOTE: DSPAM and libdspam are distributed under the GPL license, not the LGPL. Commercial licensing is available for those who seek to redistribute DSPAM or some of DSPAM's components/libraries in their non-GPL products. Please contact us for more information about commercial licensing.
The DSPAM package is split up into the following pieces:
DSPAM AGENT
The DSPAM agent is the command center for all shell and daemon operations. If you're using DSPAM as a filtering solution, this is the 'dspam' (or dspamc) binary you're likely going to be talking to via commandline.
LIBDSPAM: CORE ENGINE
The DSPAM core processing engine, also known as libdspam, provides all critical spam filtering functions. The engine is embedded into other dspam components (such as the agent) and is responsbile for the actual filtering logic. If you're not a developer, you don't need to be concerned with this component as it is automatically compiled in with the build.
WEB UI
The Web UI (User Interface) is designed to allow end-users to review their spam quarantine and history, graphs, and to delete their spam permanently. They can also optionally use the quarantine to perform all of their training. The UI also includes some basic administrative tools to change settings and manage user quarantines.
TOOLS
Some basic tools which have been provided to manage dictionaries, automate corpus feeding, and perform other diagnostic operations related to DSPAM. Some of these include dspam_train, dspam_stats, and dspam_dump.
HISTORY OF COPYRIGHT
Original work was done by Jonathan A. Zdziarski.
In 2006 the copyright was handed over to Sensory Networks.
In 2009 Sensory Networks handed over the full copyright to the DSPAM Project, represented by a team of people, including: Alexander Prinsier Dov Zamir Hugo Monteiro Ion-Mihai Tetcu Paul Cockings Stevan Bajic
1.1 INSTALLATION
IMPLEMENTATION OPTIONS
There are many different ways to deploy DSPAM onto an existing network. The most popular approaches are:
When your mail server gets ready to deliver mail to a user's mailbox it calls a delivery agent of some sort. On most UNIX systems, this is procmail, maildrop, mail.local, or a similar tool. When used as a delivery proxy, the DSPAM agent is called in place of your existing agent - or better put, it can masquerade as the local delivery agent. DSPAM then processes the message and will call the /real/ delivery agent to pass the good mail into the user's mailbox, quarantining the bad mail. DSPAM can optionally tag and deliver both spam and legitimate mail.
In the diagram below, MTA refers to Mail Transfer Agent, or your mail server software: Postfix, Sendmail, Exim, etc. LDA refers to the Local Delivery Agent: Procmail, Maildrop, etc..
BEFORE:
[MTA] ---> [LDA] ---> (User's Mailbox)AFTER:
[MTA] ---> [DSPAM] ---> [LDA] ---> (User's Mailbox)
--> [Quarantine]
[End User] ------> [Web UI]If you don't want to tinker with your existing mail server setup, DSPAM can be combined with one of a few open source programs designed to act as a POP3 proxy. This means spam is filtered whenever the user checks their mail, rather than when it is delivered. The benefit to this is that you can set up a small machine on your network that will connect to your existing mail server, so no integration is needed. It also allows your users to arbitarily point their mail client at it if they desire filtering. The drawback to this approach is that the POP3 protocol has no way to tell the mail client that a message is spam, and so the user will have to download the spam (tagged, of course).
BEFORE:
[End User] ---> [POP3 Server]AFTER:
[End User] ---> [POP3 Proxy] <--> [DSPAM]
--> [POP3 Server]Newer versions of DSPAM have seen features that allow it to function more easily as an SMTP relay. An SMTP relay sits in front of your existing mail server (requiring no integration). To use an SMTP relay, the MX records for your domains are repointed to the relay machine running DSPAM. DSPAM then relays the good (and optionally bad) mail to the existing SMTP server. This allows you to use DSPAM with even a Windows-based destination mail server as no integration is necessary. See doc/relay.txt for one example of how to do this with Postfix.
BEFORE:
{ Internet } ---> [Company Mail Server]
AFTER:
{ Internet } ---> [ Inbound SMTP Relay ] ---> [Company Mail Server] ( MTA <> DSPAM ) SMTP or --> [Quarantine] LMTP [End User] ------> [Web UI]
UPGRADING DSPAM
Please see the file UPGRADING
FRESH INSTALLATION
PREREQUISITES
DSPAM can use one of many different backends to store its information, and you will need to decide on one and install the appropriate software before you can build DSPAM. The following storage backends are presently available:
T mysql_drv: MySQL client libraries (and a server to connect to) T pgsql_drv: PostgreSQL client libraries (and a server to connect to) sqlite_drv: SQLite v2.7.7 or above sqlite3_drv: SQLite v3.x *T hash_drv: None (Self-Contained Hash-Based Driver)
Legend:
In general, MySQL is one of the faster solutions with a smaller storage footprint, and is well suited for both small and large-scale implementations.
The hash driver (inspired by Bill Yerazunis' CRM Sparse Spectra algorithm) is the fastest solution by far and requires no dependencies, supports an auto-extend feature to grow the file size as needed, and is very fast and compact. It does, however, lack some features (such as merged groups support) and uses a lot of memory to mmap() users.
Documentation for any additional setup of your selected storage driver can be found in the doc/ directory. You'll need to follow any steps outlined in the storage driver documentation before continuing.
You can download MySQL from http://www.mysql.com. You can download PostgreSQL from http://www.postgresql.com. You can download SQLite from http://www.sqlite.org.
CONFIGURATION
DSPAM uses autoconf, so configuration is fairly standardized with other UNIX-based software:
./configure [options]
DSPAM supports the configuration options below. Generally, the default configuration is more than acceptable, so it's a good idea not to tweak too many settings unless you know what you are doing.
PATH SWITCHES
--prefix=DIR Specify an alternative root prefix for installation. The default is /usr/local. This does not affect the location of dspam.conf (which defaults to /etc). Use --sysconfdir= for this.
--sysconfdir=DIR Specify an alternative home for the dspam.conf file. The default is /etc.
--with-dspam-home=DIR Specify an alternative DSPAM home for installation. This can alternatively be changed in dspam.conf, but is convenient to do on the configure line. The default is $prefix/var/dspam, or /usr/local/var/dspam.
--with-logdir=DIR Specify an alternative log directory. The default is $dspam_home/log. Do not set this to /var/log unless DSPAM will have permissions to write to the directory.
FILESYSTEM SCALE
The default filesystem scale is "small-scale", and writes each user to its own directory in the top-level DSPAM home data directory. The following two switches allow the scale to be changed to be more suitable for larger installations.
--enable-large-scale Switch for large-scale implementation. User data will be stored as $HOME/data/u/s/user instead of $HOME/data/user
--enable-domain-scale Switch for domain-scale implementation. When used, DSPAM expects username@domain to be passed in as the user id and user data will be stored as $HOME/data/domain.com/user and $HOME/opt-in/domain/user.dspam instead of $HOME/data/user
INTEGRATION SWITCHES
--with-storage-driver=DRIVER[,DRIVER2[...,DRIVERN]] Specify your storage driver selection(s). A storage driver is a driver written specifically for DSPAM to store tokens, signature data, and perform other proprietary operations. The default driver is hash_drv. The following drivers have been provided:
mysql_drv: MySQL Drivers pgsql_drv: PostgreSQL Drivers sqlite_drv: SQLite v2.x Drivers sqlite3_drv: SQLite v3.x Drivers hash_drv: Self-Contained Hash Database
If you are a packager, or wish to have multiple drivers built for any reason, you may specify multiple drivers by separating them with commas. This will cause the storage driver specified in dspam.conf to be dynamically loaded at runtime rather than statically linked. If you wish to build only one driver, but dynamically, then specify it twice as in --with-storage-driver=mysql_drv,mysql_drv.
If you will be compiling DSPAM to operate as a server daemon or to deliver via SMTP/LMTP, you will need to use a thread-safe driver (outlined in the chart earlier in this document).
You may also need to use some of the driver-specific configure flags (discussed in the DRIVER SPECIFIC CONFIGURATION OPTIONS section below).
--disable-trusted-user-security Administrators who wish to disable trusted user security may do so by using this configure flag. This will cause DSPAM to treat each user as if they were "trusted" which could allow them to potentially execute arbitrary commands on the server via DSPAM. Because of this, administrators should only use this option on either a closed server, or configure their DSPAM binary to be executable only by users who can be trusted. This option SHOULD NOT be used as a solution to your MTA dropping privileges prior to calling DSPAM. Instead, see the TRUSTED SECURITY section of this document.
--enable-homedir When enabled, instead of checking for $HOME/$USER/opt-in/ $USER[.dspam|.nodspam], DSPAM will check for a .dspam|.nodspam file in the user's home directory. DSPAM will also store each user's data in ~/.dspam when this option is enabled. Because of this, DSPAM will automatically install and run setuid root so that it can read each user's home directory.
Note:
This function is incompatible with most implementations of the Web UI, since it requires access to read each user's home directory. Therefore, only use this option if you will not be using the Web UI or plan on doing something asinine like running it as root.
--enable-daemon Builds DSPAM with support for daemon mode, and builds associated dspamc thin client. Pthreads is required to build for daemon mode and the storage driver used must be thread-safe.
DRIVER SPECIFIC CONFIGURE SWITCHES
Some storage drivers have their own custom configuration switches:
mysql_drv: --with-mysql-includes=DIR Specify a path to the MySQL includes
--with-mysql-libraries=DIR Specify a path to the MySQL libraries (Currently links to -lmysqlclient, also -lcrypto on some systems)
--enable-virtual-users Tells DSPAM to create virtual user ids. Use this if your users don't actually exist on the system (e.g. in /etc/passwd if using a password file)
--enable-preferences-extension MySQL supports the preferences extension, which stores user preferences in mysql instead of flat files (the built-in method)
--disable-mysql4-initialization If you are compiling libdspam for use with a third party application, and the third party application makes its own calls to libmysqlclient, you should use this option to disable libdspam's initialization and cleanup of libmysqlclient, and allow the application to manage this. This option suppresses libdspam's calls to mysql_server_init and mysql_server_end.
Note:
Please see the file doc/mysql_drv.txt for more information about configuring the mysql_drv storage driver.
pgsql_drv: --with-pgsql-includes=DIR Specify a path to the PgSQL includes
--with-pgsql-libraries=DIR Specify a path to the PgSQL libraries (Currently links to -lpq, and netlibs on some systems)
--enable-virtual-users Tells DSPAM to create virtual user ids. Use this if your users don't actually exist on the system (e.g. in /etc/passwd if using a password file)
--enable-preferences-extension Postgres supports the preferences extension, which stores user preferences in pgsql instead of flat files (the built-in method)
Note:
Please see the file doc/pgsql_drv.txt for more information about configuring the pgsql_drv storage driver.
sqlite_drv: sqlite3_drv: --with-sqlite-includes=DIR Specify a path to the SQLite includes
--with-sqlite-libraries=DIR Specify a path to the SQLite libraries
DEBUGGING SWITCHES
--enable-debug Turns on support for debugging output. This option allows you to turn on debugging messages for all or some users by editing dspam.conf or setting --debug on the commandline. Enabling debug in configure only adds support for debug to be compiled in, it must still be activated using one of the options prescribed above. Debugging support itself doesn't use up very many additional resources, so it should be safe to leave enabled on non-enterprise class systems.
--enable-verbose-debug Turns on extremely verbose debugging output. --enable-debug is implied. Never use this on production builds!
Note:
When verbose debug is compiled in, DSPAM performs many additional mathematical calculations regardless of whether or not it's been activated. You shouldn't use --enable-verbose-debug for production builds unless you have serious issues you can't resolve.
FEATURE ACTIVATION
--enable-clamav Enables support for Clam Antivirus. DSPAM can interface directly with clamd to perform virus scanning and can be configured to react in different ways to viruses. See dspam.conf for more information.
ADDITIONAL CONFIGURATION OPTIONS
The remainder of configuration options are located in dspam.conf, which is installed in sysconfdir (default: /usr/local/etc) upon a make install. It is generally a good idea to review dspam.conf and make any changes necessary prior to using DSPAM.
BUILDING AND INSTALLING
After you have run configure with the correct options, build and install DSPAM by performing:
make && make install
Note:
If you are a developer wanting to link to the core engine of dspam, libdspam will be built during this process. Please see the example.c file for examples of how to link to and use libdspam. Static and dynamic libraries are built in the .libs directory. Needed headers will be installed in $prefix$/include/dspam.
PERMISSIONS
In the typical UNIX environment, you'll need to worry about the following permissions:
The CGI User: This is the user your web server (most likely Apache) is running as. This is commonly 'nobody' or 'web'. You can find this in Apache's httpd.conf by searching for 'User'. The CGI user will need the ability to access the following components of DSPAM:
The MTA User: This is the user your mail server software is running as when it executes DSPAM. This is usually daemon, mail, exim, etc. This is typically different from the user the MTA runs and polices itself as, to avoid security problems. Consult your MTA's documentation for more info. The MTA user will require:
Systems Administrators: In order to perform administrative functions, systems administratiors will require:
Note:
If the MTA is communicating with DSPAM via LMTP (explained later), then execution permissions are not necessary
Note about FreeBSD:
FreeBSD's default MTA user is 'mailnull' FreeBSD's default delivery agent also changes its uid, and so in order to call it, dspam must be installed as setuid root to work on the commandline properly. This is done automatically on install.
Understanding Trusted User Security
DSPAM has tighter security for untrusted users on the system to prevent them from touching other user's data or passing arbitrary commands to the delivery agent DSPAM calls. "Trusted User Security" is a simple system whereby any unsafe functions are not available to a user calling dspam unless they are within dspam.conf's trusted user list.
Local non-privileged users should be able to use DSPAM without any problems while remaining untrusted, as long as they behave. For example, an untrusted user cannot set their DSPAM username to any name other than their username. Untrusted users are also limited to the delivery options set by the system administrator, and cannot redirect how DSPAM delivers mail.
A list of trusted users is maintained in dspam.conf. This file should include a list of trusted users who should be allowed to set the dspam user, passthru parameters, and other information that would be potentially dangerous for a malicious user to be able to set. You'll need to ensure that your CGI user, MTA user, and system administrators are on the list.
MAIL SERVER INTEGRATION
As previously mentioned, there are three popular ways to implement DSPAM:
As a delivery proxy: The default approach integrates DSPAM directly with the mail server and filters spam as mail comes in. Please see the appropriate instructions in doc/ pertaining to your MTA.
As a POP3 proxy: This alternative approach implements a POP3 proxy where users connect to the proxy to check their email, and email is filtered when being downloaded. The POP3 proxy is a much easier approach, as it requires much less integration work with the mail server (and is ideal for implementing DSPAM on Exchange, etcetera). Please see the file doc/pop3filter.txt.
As an SMTP Relay: DSPAM can be configured as an SMTP relay, a.k.a appliance. You can set it up to sit in front of your real mail server and then point your MX records at it. DSPAM will then pass along the good mail to your real SMTP server. See doc/relay.txt for more information. The example provided uses Postfix and MySQL.
Trusted users and the MTA
If you are using an MTA that changes its userid to match the destination user before calling DSPAM, you won't be able to provide pass-thru arguments to DSPAM (these are the commandline arguments that DSPAM in turn passed to the local delivery agent, in such a configuration). You will need to pre-configure the "default" pass-thru arguments in DSPAM. This can be done by declaring an untrusted delivery agent in dspam.conf. When DSPAM is called by an untrusted user, it will automatically force their DSPAM user id and passthru delivery agent arguments specified in dspam.conf.
This information will override any passthru commandline parameters specified by the user. For example:
UntrustedDeliveryAgent "/bin/mail -d $u"
The variable $u informs DSPAM that you would like the destination username to be used in the position $u is specified, so when DSPAM calls your LDA for user 'bob', it will call it with:
/bin/mail -d bob
ALIASES
There are essentially two different ways a user might train DSPAM. The first is by using the Web UI, which allows them to retrain via the "History" tab. This works quite well, as users must visit the Web UI occasionally to review their quarantine anyway (and reverse any false positives). We'll discuss this shortly in section 1.1.8.
The more common approach to training, discussed here, is to allow users to simply forward their spam to an email address where DSPAM can analyze and learn it. DSPAM uses a signature-based system, where a serial number of sorts is appended to each email processed by DSPAM. DSPAM reads this serial number when the user forwards (or bounced) a message to what is called their "spam email address". The serial number points to temporary information stored on the server (for 14 days by default) containing all of the information necessary for DSPAM to relearn the message. This is necessary in order to relearn the exact message DSPAM originally processed.
Note:
If you are using an IMAP based system, Web-based email, or other form of email management where the original messages are stored on the server in pristine format, you can turn this signature feature off by setting "TrainPristine on" in dspam.conf. DSPAM will then use the message itself that you provide it to train, which MUST be identical to the original message in order to retrain properly.
Because DSPAM learns each user's specific email behavior, it's necessary to identify the user in order to program their specific filtering database. This can be done in one of three ways:
The Simple Way:
If you are using the MySQL or PgSQL storage drivers, the original numeric user id can be embedded in the signature, requiring only one central spam alias to be necessary for the entire system. To configure this, uncomment the appropriate UIDInSignature option in dspam.conf:
Now all you'll need is a single system-wide alias, and DSPAM will train the appropriate user when it sees the signature. An example of an alias might look like:
spam:"|/usr/local/bin/dspam --user root --class=spam --source=error"
Similarly, you may also wish to have a false-positive alias for users who prefer to tag spam rather than quarantine it:
notspam:"|/usr/local/bin/dspam --user root --class=innocent --source=error"
Note:
The 'root' user represents any active dspam user. It is necessary to supply a username on the commandline or DSPAM will bail on an error, however the user will be changed internally once the signature is read.
The Kind-of-Simple Way:
If you're not using one of the above storage drivers, the next easiest way to configure aliases is to have DSPAM parse the 'To:' header of the message and use a catch-all subdomain to direct all mail into DSPAM for retraining. You can then instruct your users to email addresses like '[email protected]'. The ParseToHeaders option (available in dspam.conf) will parse the To: header of forwarded messages and set the username to either 'bob' or '[email protected]', depending on how it is configured. DSPAM can also set the training mode to either "learn spam" or "learn notspam" depending on whether the user specified a spam- or notspam- address in the To: header.
This is ideal if you don't want to set up a separate alias for each user on your system (The Hard Way). If you're fortunate enough to have a mail server that can perform regular expression matching, you can set up your system without a subdomain, and just use addresses like [email protected]. For the rest of us, it will be necessary to set up a subdomain catch-all directly into DSPAM. For example:
@relearn.domain.tld "|/usr/local/bin/dspam"
Don't forget to set the appropriate ParseToHeaders and related options in dspam.conf as well. More specific instructions can be found in dspam.conf itself. In most cases, the following will suffice:
ParseToHeaders on ChangeUserOnParse user ChangeModeOnParse on
The Old Way (A.K.A. The Hard Way)
If neither of the easy ways are possible, you're stuck with doing it the hard way. This means you'll need a separate spam alias (and notspam alias, if users are tagging mail) for each user. To do this, you will need to create an email address for each user, so that DSPAM can analyze and learn for that specific user. For example:
spam-bob: "|/usr/local/bin/dspam --user bob --class=spam --source=error"
You will end up having one alias per mail user on the system, two if you do not use DSPAM's CGI quarantine (an additional one using notspam-). Be sure the aliases are unique and each username matches the name after the --user flag. A tool has been provided called dspam_genaliases. This tool will read the /etc/passwd file and write out a dspam aliases file that can be included in your master aliases table.
To report spam, the user should be instructed to forward each spam to spam-user@yourhost
It doesn't really matter what you name these aliases, so long as the flags being passed to dspam are correct for each user. It might be a good idea to create an alias custom to your network, so that spammers don't forward spam into it. For example, notspam-yourcompany-bob or something.
Note About Security:
You might be wondering if a user can forward a spam to another user's address, or whether a spammer can forward a spam to another user's notspam address. The answer is "no". The key to all mail-based retraining is the signature embedded in each email. The signature is stored with each user's own user id, and so not only does the incoming message have to bear a valid signature, but it also has to be stored on the system with the correct user id. This prevents any kind of alias abuse.
NIGHTLY MAINTENANCE AND HOUSEKEEPING CRONS
Non-SQL Based Nightly Purge
If you are NOT running a SQL-based solution, then you should configure dspam_clean to run under cron nightly. This clean tool will read all signature databases and purge signatures that are older than 14 days (configurable), purge abandoned tokens, and remove unimportant tokens. Without this tool, old signatures will continue to pile up. Be sure the user running cleanup has full read/write permissions on the DSPAM data files.
0 0 * /usr/local/bin/dspam_clean [options]
See the dspam_clean description for more information
SQL-Based Nightly Purge
SQL-Based solutions include a nightly SQL script to perform the same basic tasks as dspam_clean, and it does it much faster and with more finesse. You can find instructions about each driver's purge functions in the driver's README (doc/[driver].txt) for performing nightly maintenance. Most SQL drivers will include a purge script in the src/tools.[driver] directory. For example:
0 0 * mysql --user=[user] --pass=[pass] [db] < /path/to/purge-4.1.sql
Log Rotation
The system log and user logs can fill up fairly quickly, when all that's really needed to generate graphs are the last two to three weeks of data. You can configure a nightly log cleanup using dspam_logrotate:
0 0 * dspam_logrotate -a 30 -d /usr/local/var/dspam/data
NOTIFICATIONS
DSPAM is capable of sending three different notifications to users:
A "First Run" message sent to each user when they receive their first message through DSPAM.
A "First Spam" message sent to each user when they receive their first spam
A "Quarantine Full" message sent to each user when their quarantine box is > 2MB in size (note: the 2MB limit is hardcoded in DSPAM).
These notifications can be activated by copying the txt/ directory from the distribution into DSPAM's home (by default /usr/local/var/dspam).
Example: /usr/local/var/dspam/txt/firstrun.txt /usr/local/var/dspam/txt/firstspam.txt /usr/local/var/dspam/txt/qurantinefull.txt
You will want to modify these templates prior to installing them to reflect the correct email addresses and URLs (look for 'configureme' and 'yourdomain').
NOTE: The quarantine warning is reset when the user clicks 'Delete All', but is not reset if they use "Delete Selected". If the user doesn't wish to receive reminders, they should use the "Delete Selected" function instead of "Delete All".
You'll need to also set "Notifications" to "on" in dspam.conf.
THE WEB UI
The Web UI (CGI client) can be run from any executable location on a web server, and detects its user's identity from the REMOTE_USER environment variable. This means you'll need to use HTTP password authentication to access the CGI (Any type of authentication will work, so long as Apache supports the module). This is also convenient in that you can set up authentication using almost any existing system you have. The only catch is that you'll need the usernames to match the actual DSPAM usernames used the system. A copy of the shadow password file will suffice for most common installs.
The accompanying files in the webui/ folder should be copied into your document root and cgi-bin, as specified.
Note:
Some authentication mechanisms are case insensitive and will authenticate the user regardless of the case they type it in. DSPAM, on the other hand, is case sensitive and the case of the username used will need to match the case on the system. If you suffer from this authentication problem, and are certain all of your users' usernames are in lowercase, you can add the following line of code to the CGI right after the call to &ReadParse...
$ENV{'REMOTE_USER'} = lc($ENV{'REMOTE_USER'});
The CGI will need to function in the same group as the dspam agent in order to work with the files in dspam_home. The best way to do this is to create a separate virtualhost specifically for the CGI and assign it to run in the MTA group using Apache's suexec. If you are using procmail, additional configuration may also be necessary (see below).
Note:
Apache users do NOT take on the identity of the groups specified in /etc/group so you will need to specifically assign the group in httpd.conf.
Note about Procmail:
Because the DSPAM Web UI is a CGI script, DSPAM will not retain its setuid privileges when called. If you are running procmail, this will become a problem as procmail requires root privileges to deliver. The easiest hack around this is to create a procmail.dspam binary and make it setuid root, then make it executable only by the mail group (or whatever group DSPAM and the CGI run in).
The DSPAM Web UI has a minimal configuration inside the configure.pl script. You'll want to check and make sure all of the settings are correct. In most cases, the only that will be necessary to change are the large-scale or domain-scale flags.
BEFORE PROCEEDING: Check and make sure (Again) that the CGI user from Apache's httpd.conf is added as a trusted user in dspam.conf.
Default Preferences
Now would be a good time to set the system's default preferences. This can be done using the dspam_admin tool. For example:
dspam_admin ch pref default trainingMode TEFT dspam_admin ch pref default spamAction quarantine dspam_admin ch pref default spamSubject "[SPAM]" dspam_admin ch pref default enableWhitelist on dspam_admin ch pref showFactors off
The default preferences are used for any users who have not yet set their own preferences. You can also control which preferences the user may override by changing the "AllowOverride" settings in dspam.conf.
By default, the parameters specified on the commandline will be used (if any). If, however, a preference is found for the particular user those preferences will override the commandline.
GD Graphing Library
If you plan on leaving DSPAM's logging function enabled, and would like to produce pretty graphs for your users, the graph.cgi script requires the following be installed on your machine:
GD Graphics Library (http://www.boutell.com/gd/) Compile with png support
The following PERL modules: (http://www.perl.com/CPAN/modules/by-module/GD/)
. GD . GD-Graph3d . GDGraph . GDTextUtil . CGI
Typically this can be accomplished on the commandline:
perl -MCPAN -e 'install GD::Graph3d'
Configuring Administrators
Once you've configured the Web UI, you'll want to edit the 'admins' file to contain a list of users who are permitted to use the administration suite.
Configuring Sub-Administrators / Domain Level Administrators
It is possible to delegate the management of users to a list of sub-admins/ domain level admins. To accomplish that you should edit the 'subadmins' file to contain a list of sub-admins/domain level admins which are permitted to switch their username while using the DSPAM control center.
Opt-In/Out
If you would like your users to be able to opt in/out of DSPAM filtering, add the correct option to the nav_preferences.html template, depending on your configuration (for example, if you have an opt-in system, you'll want to add the opt-in option). Note: This currently only works with the preferences extension, and not drop files.
<INPUT TYPE=CHECKBOX NAME=optIn $C_OPTIN$> Opt into DSPAM filtering
<INPUT TYPE=CHECKBOX NAME=optOut $C_OPTOUT$> Opt out of DSPAM filtering
1.2 TESTING
If you've installed from an RPM, there's a good chance that the packager went to the trouble of testing already. If you're building from sources, however, you'll need to find a way to ensure your configuration isn't broken.
Most software packages are supplied with a test suite to determine if the software is functioning properly. Since DSPAM's correct function relies primarily on having the correct permissions and mail server configuration, a test script fails to provide the level of testing required for such a package. The following exercise has been provided to test dspam's correct functioning on your system. This exercise does not test the Web UI, but only the core dspam agent.
Before running the test, you should have completed section 1.1's instructions for compiling and installing dspam as well as configured your mail server to support dspam.
Create a new user account on your system. It is important that this be a new account to prevent any unrelated email from being delivered during testing. Be sure to configure a spam alias for the test account.
Send a short (10 words or less) email to the account, and pick it up using your favorite mail client.
Run dspam_stats [username] on the server. You should see a value of 1 for "TI" or "Total Innocent" as shown below:
dspam-test 0 TP 1 TN 0 FN 0 FP
If you receive an error such as "unable to open /usr/local/var/dspam... for reading", then the dspam agent is not configured correctly. The problem could exist in either your mail server configuration or one or more of the permissions on the directory or agent. Check your configuration and permissions, and repeat this step until the correct results are experienced.
Run dspam_dump [username] to get a complete list of tokens and their statistics. Each token should have an I: (innocent) hit count of 1. The tokens will be represented as 64-bit values, for example:
3126549390380922317 S: 0 I: 1 LH: Mon Aug 4 11:40:12 2003 13884833415944681423 S: 0 I: 1 LH: Mon Aug 4 11:40:12 2003 14519792632472852948 S: 0 I: 1 LH: Mon Aug 4 11:40:12 2003 8851970219880318167 S: 0 I: 1 LH: Mon Aug 4 11:40:12 2003
To view statistics for a particular token, run dspam_dump [username] [token] where token is the plain-text token value. For example:
% dspam_dump bill FREE 7717766825815048192 S: 00265 I: 00068 P: 0.7358
Forward the test message to the spam alias you've created for the test account. Provide enough time for the message to have processed.
Run dspam_stats [username] on the server again. Now, the value for TN should be zero and the value for FN (false negatives) should be 1 as shown below:
dspam-test 0 TP 0 TN 1 FN 0 FP
If this is not the case, check the group permissions of the dspam agent as well as the permissions your MTA uses when piping to aliases.
3126549390380922317 S: 1 I: 0 LH: Mon Aug 4 11:44:29 2003 13884833415944681423 S: 1 I: 0 LH: Mon Aug 4 11:44:29 2003 14519792632472852948 S: 1 I: 0 LH: Mon Aug 4 11:44:29 2003 8851970219880318167 S: 1 I: 0 LH: Mon Aug 4 11:44:29 2003
If you have some tokens that do not have an S: of 1 or an I: of 0, the dspam signature was not found on the email, and this could be due to a lot of things.
1.3 TROUBLESHOOTING
Problem: No files are being created in the user directorySolution: Check the directory permissions of the directory. The user directory must be writable by the user the dspam agent is running as as well as the CGI user.
Problem: False positives are never being deliveredSolution: Your CGI most likely doesn't have the privileges required by the LDA to deliver the messages. Make sure the CGI user is in the correct group. Also consider setting the dspam agent to setuid or setgid with the correct permissions.
Problem: My database is getting huge!Solution: DSPAM's default training mode is TEFT. On top of this, the purging defaults are very lax. You might consider switching to TOE (Train-on-Error) mode training if you require a minimal database. If you are willing to sacrifice accuracy for disk space, disabling the 'chain' tokenizer from dspam.conf will prevent the use of multi-word (chained) tokens, which will also cut your database size considerably. You may also consider more frequent calls to dspam_clean -p to purge neutral data, which comprises a majority of most databases.
For more help, please see the DSPAM FAQ at http://dspam.sf.net.
1.4 DSPAM TOOLS
A few useful tools have been provided to make DSPAM management a bit easier. These tools include:
dspam_admin - A tool used to perform specific administrative functions. These functions are usually included as part of an extensions package (such as the preferences extension). Available functions are listed in the tool's usage output.
dspam_train - Used to train and test a corpus of ham and spam (in maildir format). Syntax: dspam_train [username] [spam_dir] [nonspam_dir] where username is the username of the user to apply the training to, and the two dirs represent directories containing messages in individual files (e.g. maildir/corpus format). dspam_train can be used on an existing user's database, to further improve accuracy, or to train from scratch. it also provides a solid test jig for testing the efficiency and accuracy of a test corpus against the filter. NOTE: dspam_train will automatically balance training of the corpus to ensure both spam and nonspam are trained based on the ratio of spam/nonspam. this means if you have twice as much spam as nonspam, two spam will be trained for every nonspam.
dspam_dump - Dumps a DSPAM dictionary. This can be used to view the entire contents of a user's dictionary, or used in combination with grep to view a subset of data. Syntax: dspam_dump [username] [token] where username is the DSPAM user's username. If a token is specified, statistics only for that token will be printed.
dspam_clean - Performs nightly housecleaning by deleting old or useless data from user data. dspam_clean performs the following operations:
1. Using the -s flag, dspam_clean will continue to perform stale signature
purging. If an age is specified, for example -s14, the age defined as the
default will be overridden. Specifying an age of 0 will delete all
signatures for the users processed.
2. Using the -p flag, dspam_clean will delete all tokens from a user's
database whose probability is between 0.35 and 0.65 (fairly neutral,
useless tokens) that fall beyond the default age. If an age is specified,
for example -p30, the age defined as the default will be overridden. It
is a good idea to use this type of clean with an age of 0 on users after
a lot of corpus training.
3. Using the -u flag, dspam_clean will delete all unused tokens from a
user's database. There are four different types of unused tokens:
- Tokens which have not been used for a long time
- Tokens which have a total hit count below 5
- Tokens which have only one spam hit
- Tokens which have only one innocent hitAges may be overridden by specifying a format such as -u30,15,10,10 where each number represents the respective age. Specifying an age of zero will delete all unused tokens in the category. Defaults are set in dspam.conf.
Optionally, usernames may be specified to override the default behavior of processing all users.
Examples:
Process all users on the system using all clean operations: dspam_clean -s -p15 -u90,30,15,15
Delete all of user 'dick' and 'jane's signatures: dspam_clean -s0 dick jane
Perform a post-corpus training clean on user 'spot': dspam_clean -p0 -u0,0,0,0 spot
Run dspam_clean with all default options, all clean modes enabled, on all users on the system: dspam_clean -s -p -u
NOTE: You may wish to only run certain cleaning modes depending on the type of storage driver you are using. For example, the MySQL storage driver includes a script which performs signature and unused token operations, leaving only probability operations as useful. If you are using a SQL-based storage driver, it is strongly recommended that you use the maintenance scripts wherever possible for optimum efficiency.
dspam_stats - Displays the spam statistics for one or all users on the system. Syntax: dspam_stats [username]. If no username is provided, all users will be displayed. Displays TP (true positives), TN (true negatives), FN (false negatives), and FP (false positives).
dspam_genaliases - Reads the /etc/passwd file and outputs a dspam aliases table which can be included in the master aliases table. You may try Art Sackett's generate_dspam_aliases tool at http://www.artsackett.com/freebies/generate_dspam_aliases/ if you need some better functionality. This will eventually be merged in as a replacement for the existing tool.
dspam_merge - Merges multiple users' dictionaries together into one user's dictionary (does not affect the merge users). This can be used to create a seeded dictionary for a new user, or to copy a single user's dictionary to a new file. This is great for building global dictionaries, but crunches a lot of time and disk.
1.5 AGENT COMMANDLINE ARGUMENTS
The DSPAM agent (dspam) recognizes the following commandline arguments:
--user [user1 user2 ... userN] Specifies the destination user(s) of the incoming message. DSPAM then processes the message once for each user individually. If the message is to be delivered, the $u (or %u) parameters of the arguments string will be interpolated for the current user being processed.
--class=[spam|innocent] Tells DSPAM that the message being presented has already been classified by the user. This flag should be used when a misclassification has occurred, when the user is corpus-feeding a message, or an inoculation is being presented. This flag must be used in conjunction with the --source flag. Providing no classification invokes the SOP of DSPAM, which is to determine the message's nature on its own.
--source=[error|corpus|inoculation] Wherever --class is used, the source of the user-provided classification must also be provided. The source is very important and dramatically affects DSPAM's training behavior:
error: The message being presented was a message previously misclassified
by DSPAM. When 'error' is provided as a source, DSPAM requires that
the DSPAM signature be present in the message, and will use the
signature to recall the original training metadata. If the signature
is not present, the message will be rejected. In this source mode,
DSPAM will also decrement each token's previous classification's
count as well as the user totals.
You should use error only when DSPAM has made an error in
classifying the message, and should present the modified version of
the message with the DSPAM signature when doing so.corpus: The message being presented is from a mail corpus, and should be trained as a new message, rather than re-trained based on a signature. The message's full headers and body will be analyzed and the correct classification will be incremented, without its opposite being decremented.
You should use corpus only when feeding messages in from corpus, not
for correcting errors.inoculation: The message being presented is in pristine form, and should be trained as an inoculation. Inoculations are a more intense mode of training designed to cause DSPAM to train the user's metadata repeatedly on previously unknown tokens, in an attepmt to vaccinate the user from future messages similar to the one being presented.
You should use inoculation only on honeypots and the like.--deliver=[spam,[innocent|nonspam],summary,stdout] Tells DSPAM to deliver the message if its result falls within the criteria specified. For example, --deliver=innocent or --deliver=nonspam will cause DSPAM to only deliver the message if its classification has been determined as innocent. Providing --deliver=innocent,spam or --deliver=nonspam,spam will cause DSPAM to deliver the message regardless of its classification. This flag provides a significant amount of flexibility for nonstandard implementations, where false positives may not be delivered but spam is, and etcetera.
summary : Deliver (to stdout) a summary indentical to the output of message
classification:
X-DSPAM-Result: User; result="Innocent"; class="Innocent";
probability=0.0000; confidence=1.00;
signature=4b11c532158749980119923
stdout : Is a shortcut for for --deliver=innocent,spam --stdout--stdout If the message is indeed deemed "deliverable" by the --deliver flag, this flag will cause DSPAM to deliver the message to stdout, rather than the configured delivery agent.
--process Tells DSPAM to process the message. This is the default behavior, and the flag is implied unless --classify is used - but is a good idea to use to avoid ambiguity.
--classify Tells DSPAM only to classify the message, and not make any writes to the user's metadata or attempt to deliver/quarantine the message.
NOTE: The output of the classification is specific to the user, not including the output of any groups they might be affiliated with, so it is entirely possible that the message would be caught as spam by the group, even if it didn't appear in the classification. If you want to get the classification for the GROUP, use the group name as the user instead of an individual.
--signature=[signature] For some implementations, the admin may wish to pass the signature in via commandline instead of allowing DSPAM to find it on its own. This is especially useful when front-ending the agent with other tools. Using this option will set the active signature and will also forego reading of stdin.
--mode=[toe|tum|teft|notrain|unlearn] Configures the training mode to be used for this process:
teft: Train-Everything. Trains on all messages processed. This is
a very thorough training approach and should be considered the
standard training approach for most users. TEFT may, however,
prove too volatile on installations with extremely high per-user
traffic, or prove not very scalable on systems with extremely large
user-bases. In the event that TEFT is proving ineffective, one of
the other mo