996e39f3e9
domains/ips listed in these files are *NOT* filtered, even if listed in domains.txt or ips.txt. someone added netcom.com to the domains.txt file, resulting in all mail from netcom.com being blocked.
96 lines
3.8 KiB
Plaintext
96 lines
3.8 KiB
Plaintext
Filtering out SPAM from your site
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Introduction:
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The FreeBSD Project filters spam, unsolicited commerical
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e-mail, from its mailing lists. The filter has two parts: databases
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and rulesets. We have rulesets to /etc/sendmail.cf, check_rcpt,
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check_relay, check_rbl, check_mail and xlat. (xlat is for testing
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only, as explained in /etc/mail/sendmail.cf.additions.) These
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rulesets use three databases. The denyip, a list of IP addresses,
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spamsites, a list of domains, and fakenames, a list of bogus
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usernames (such as investor and success). We do not accept mail
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from any machine that matches a entry in either database, or users
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in the fakenames database.
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WARNING: We do not maintain the database source files.
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Read domain.txt and ips.txt.
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(Make will fetch them for you)
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Domains that you want to allow, should be added
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to the file /etc/mail/allowed_domains.txt.
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IP addresses that you want to allow, should be added
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to the file /etc/mail/allowed_ips.txt.
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Filtering at your site:
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To filter spam at your site you need to:
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1. modify your /etc/sendmail.cf,
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2. retrieve the database source files from the master site,
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3. make the databases and
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4. finally signal sendmail that the configuration file has changed.
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1. Modifying your /etc/sendmail.cf
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Add the database declarations and the rulesets contained
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in /etc/mail/sendmail.cf.additions to your .mc file. If you do
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not use m4 to generate your /etc/sendmail.cf, add the database
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declarations to your /etc/sendmail.cf.
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2. Fetching the database source files:
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The database source files are available from Gulf Coast
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Internet via anonymous FTP. The Makefile in /etc/mail will retreive
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the source files for you: as root, type "cd /etc/mail; make" at
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the command line. The previous version of the database source
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files is moved to <filename>.0.
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Local additions should be kept in separate files. We use
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spamsites.local and denyip.local. You may want to diff the new
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versions of the files against the previous versions to see what
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has changed.
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Local deletions should be kept in separate files. We use
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allowed_domain.txt and allowed_ips.txt. (This feature was added
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after netcom.com was added to the spam block list.)
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3. Make the databases:
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As root, type "cd /etc/mail; make install" will build the
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two databases from the retrieved source files and the local additions
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files.
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4. Signaling sendmail:
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Sendmail will reread its configuration whenever sendmail
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receives a HUP signal. As root, type "kill -HUP `cat
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/var/run/sendmail.pid`". Check sendmail's log file to be sure that
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it has restarted. /var/log/maillog should contain the line: "Oct
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15 08:59:16 hub sendmail[6565]: restarting /usr/sbin/sendmail on
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signal". Most likely, the date, time, hostname and process id will
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be differ.
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Testing the spam filter:
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How can I tell if its working:
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The mail log file, /var/log/maillog, will contain a line
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for every message filtered. The lines will be similar to one of
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these two log entries:
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Check_mail rejects:
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Oct 15 02:43:26 hub sendmail[6565]: CAA06565: ruleset=check_mail,
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arg1=<announce@martianconsulate.com>, relay=xxx.isp.net [###.###.###.###],
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reject=521 <announce@martianconsulate.com>
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Nov 30 15:56:37 hub sendmail[15058]: PAA15058: ruleset=check_mail,
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arg1=<ultramax@s2.eddelwissl.NET>, relay=relay.somewhere.com
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[###.###.###.###], reject=451 <ultramax@s2.eddelwissl.NET>... Domain
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does not resolve
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Check_relay rejects:
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Oct 19 04:45:24 hub sendmail[3503]: NOQUEUE: ruleset=check_relay,
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arg1=imsp015.netvigator.com, arg2=205.252.144.206, relay=root@localhost,
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reject=521 blocked.contact postmaster@FreeBSD.ORG
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check_rcpt reject:
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Nov 30 15:04:08 hub sendmail[12390]: PAA12390: ruleset=check_rcpt,
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arg1=investor@100percent.per.year.com, relay=newfed.frb.gov
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[198.3.221.5], reject=553 investor@100percent.per.year.com...
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521<investor@100percent.per.year.com>#blocked.contact postmaster
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Sun Nov 16 11:40:53 PST 1997
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