NAME

qmail-rblchk - filter all incoming mail and check if it comes from RBL listed IPs.

SYNOPSIS

| qmail-rblchk [ options ] [ /SpamDir/ ]

DESCRIPTION

qmail-rblchk is used in .qmail files to check the IP address from the Received: from lines. It has the same function as rblsmtpd(1) , but the messages are checked at local delivery time. With this you can check the content of the message by simply redirecting it to another mailbox or address.
If a directory is given with /SpamDir/ parameter, all spam message are delivered to that directory if it exist and is in Maildir format. The directory name must start with a / or . (dot) and end with a /.

OPTIONS

General options:

-h: show help screen
-s: add X-Spam header to the incoming mail (work only with delivery to ``/SpamDir/'')
-c: turn on condredirect(1) compatibility mode
-i NUM: ignore first NUM IP addresses found in the header
-x IP: do not check IP , try to find other address in header
-v: verbose (debug) mode
-V: show program version
-p: don't check private IP class: 127.0.0.0 - 127.255.255.255 10.0.0.0 - 10.255.255.255 172.16.0.0 - 172.31.255.255 192.168.0.0 - 192.168.255.255
-q: quiet mode (suppress any output)
-m: check all IP in the email (default: check only first IP address)
-l log: write program action to log file
-L data: write blocked IP to data file

Control options:

-r addr: use addr for RBL checking (block mail if TXT record exists)
-R addr: use addr for RBL reverted checking (block mail if TXT record does NOT exist)
-a addr: use addr for anti-RBL checking (block mail if A record does NOT exist)
-A addr: use addr for anti-RBL reverted checking (block mail if A record exist)
-C addr: use addr for one time RBL checking (don't block mail if A or TXT record exist)
-X cdb: check if IP is listed in cdb file, see tcprules(1) or EXAMPLES section for the format

You must specify one or more (max 32) RBL address or a CDB file, example:

  -r dnsbl.sorbs.net -r sbl-xbl.spamhaus.org -r relays.ordb.org
  -X rule.cdb -r relays.ordb.org

You can ignore (-x option) no more than 16 IP address.

EXIT CODES

The program exit status in normal mode: 0 when the message is not blocked 100 when the message is blocked 111 when the program fails or no options were given

In delivery mode: 0 the message is not blocked (continue .qmail checking) 99 the blocked message has been written to ``SpamDir'' Maildir 111 when the program fails or no options were given

In condredirect compatibility mode: 0 when the message is blocked 1 when the message is not blocked 111 when the program fails or no options were given

EXAMPLES

There are some examples of qmail-rblchk use, please use them carefully to prevent loss of mail.

We check bl.spamcop.net and dialups.mail-abuse.org RBL list. If the mail is spam, the delivery will fail, and the sender will receive a bounce message:

# we discard all suspected mail | qmail-rblchk -r dnsbl.sorbs.net -r sbl-xbl.spamhaus.org

We delivery all mail that comes from RBL listed IP addresses to our ../spam/ Maildir:

# save spam-suspected mail in another Maildir | qmail-rblchk -r dnsbl.sorbs.net -r sbl-xbl.spamhaus.org ../spam/

Same as above, but all spam messages are delivered to me-spam address with condredirect :

# save spam-suspected mail in another box | condredirect me-spam qmail-rblchk -c -r dnsbl.sorbs.net \ -r sbl-xbl.spamhaus.org

If you prefere to use a CDB file, crete a rule file like that:

# allow mails from local network 192.168.0.:allow # some spammer IPs 10.0.0.1:deny 1.2.3.4:deny

create the CDB file with:

tcprules rule.cdb rule.tmp < rule

The .qmail file is:

# save spam-suspected mail in another Maildir | qmail-rblchk -X ./rule.cdb -r sbl-xbl.spamhaus.org ../spam/

if the IP is found in rule.cdb qmail-rblchk follow the rule in the file:

allow the message is good

deny the message is spam

if the IP is not listed qmail-rblchk continue with normal RBL checking. You can insert into the CDB file a default rule (:allow or :deny), to block or accept all other IPs.

AUTHOR

Luca Morettoni <luca@morettoni.net> - http://morettoni.net

THANKS

Joerg Backschues <jbks@tca-os.de> for the English page check and testing on 300.000 users and 500.000 mails system;

Brian T Glenn <glenn@delink.net> for some option suggestions and for the disk space at USA mirror;

Emanuel Haupt <haupt@critical.ch> for the FreeBSD port and manpage hints;

Emanuel's wife for the manpage correction.

BUGS

Report me any bug, problem or other hints!