NAME

policyd-weight.conf - policyd-weight configuration parameters

STATUS

Beta, Documentation incomplete

DESCRIPTION

policyd-weight uses a perl(1) style configuration file which it reads on startup. The cache re-reads the configuration after $MAINTENANCE_LEVEL (default: 5) queries. If -f is not specified, it searches for configuration files on following locations:

/etc/policyd-weight.conf
/usr/local/etc/policyd-weight.conf
./policyd-weight.conf

CACHE SETTINGS

$CACHESIZE (default: 2000)

Set the minimum size of the SPAM cache.

$CACHEMAXSIZE (default: 4000)

Set the maximum size of the SPAM cache.

$CACHEREJECTMSG

(default: 550 temporarily blocked because of previous errors)"

Set the SMTP status code and a explanatory message for rejected mails due to cached results

$NTTL (default: 1)

The client is penalized for that many retries.

$NTIME (default: 30)

The $NTTL counter will only be decremented if the client waits at least $NTIME seconds.

$POSCACHESIZE (default: 1000)

Set the minimum size of the HAM cache.

$POSCACHEMAXSIZE (default: 2000)

Set the maximum size of the HAM cache.

$PTTL (default: 60)

After that many queries the HAM entry must succeed one run through the RBL checks again.

$PTIME (default: 3h)

after $PTIME in HAM Cache the client must pass one time the RBL checks again. Values must be nonfractal. Accepted time-units: s(econds), m(inutes), h(ours), d(ays)

$TEMP_PTIME (default: 1d)

The client must pass this time the RBL checks in order to be listed as hard-HAM. After this time the client will pass immediately for PTTL within PTIME. Values must be non-fractal. Accepted time-units: s(econds), m(inutes), h(ours), d(ays)

DEBUG SETTINGS

$DEBUG (default: 0): Turn debugging on (1) or off (0)

DNS SETTINGS

$DNS_RETRIES (default: 2): How many times a single DNS query may be repeated
$DNS_RETRY_IVAL (default: 2): Retry a query without response after that many seconds
$MAXDNSERR (default: 3): If that many queries fail, the mail is accepted with $MAXDNSERRMSG.
In total DNS queries this means: $MAXDNSERR * $DNS_RETRIES
$IGNORE_RFC1918_A (default: 0): If enabled (1) A records with RFC1918 addresses aren't treated as bogus addresses by policyd-weight and therefore bogus_mx_score isn't added.

MISC SETTINGS

$MAINTENANCE_LEVEL (default: 5): After that many policy requests the cache (and in daemon mode child processes) checks for configuration file changes
$MAXIDLECACHE (default: 60): After that many seconds of being idle the cache checks for configuration file changes.
$PIDFILE (default: /var/run/policyd-weight.pid): Path and filename to store the master pid (daemon mode)
$LOCKPATH (default: /tmp/.policyd-weight/): Directory where policyd-weight stores sockets and lock-files/directories. Its argument must contain a trailing slash.
$SPATH (default: $LOCKPATH.'/polw.sock'): Path and filename which the cache has to use for communication.
$TCP_PORT (default: 12525): TCP port on which the policy server listens (daemon mode)
$BIND_ADDRESS (default: '127.0.0.1'): IP Address on which policyd-weight binds. Currently either only one or all IPs are supported. Specify 'all' if you want to listen on all IPs.
$SOMAXCONN (default: 1024): Maximum connections which policyd-weight accepts. This is set high enough to cover most scenarios.
$USER (default: polw): Set the user under which policyd-weight runs
$GROUP (default: $USER): Set the group under which policyd-weight runs

OUTPUT AND LOG SETTINGS

$ADD_X_HEADER (default: 1)

Insert a X-policyd-weight: header with evaluation messages.
1 = on, 0 = off

$LOG_BAD_RBL_ONLY (default: 1)

Insert only RBL results in logging strings if the RBL score changes the overall score. Thus RBLs with a GOOD SCORE of 0 don't appear in logging strings if the RBL returned no BAD hit.
1 = on, 0 = off

$MAXDNSBLMSG (default: 550 Your MTA is listed in too many DNSBLs)

The message sent to the client if it was reject due to $MAXDNSBLHITS and/or $MAXDNSBLSCORE.

$REJECTMSG (default: 550 Mail appeared to be SPAM or forged. Ask your Mail/DNS-Adminisrator to correct HELO and DNS MX settings or to get removed from DNSBLs)

Set the SMTP status code for rejected mails and a message why the action was taken

RESOURCE AND OPTIMIZATIONS

$CHILDIDLE (default: 120)

How many seconds a child may be idle before it dies (daemon mode)

$MAX_PROC (default: 50)

Process limit on how many processes policyd-weight will spawn (daemon mode)

$MIN_PROC (default: 2)

Minimum child processes which are kept alive in idle times (daemon mode)

$PUDP (default: 0)

Set persistent UDP connections used for DNS queries on (1) or off (0).

SCORE SETTINGS

Positive values indicate a bad (SPAM) score, negative values indicate a good (HAM) score.

@bogus_mx_score (2.1, 0)

If the sender domain has neither MX nor A records or these records resolve to a bogus IP-Address (for instance private networks) then this check asigns the full score of bogus_mx_score. If there is no MX but an A record of the sender domain then it receives a penalty only if DNSBL-listed.

Log Entries:

BOGUS_MX
The sender A and MX records are bogus or empty.

BAD_MX
The sender domain has an empty or bogus MX record and the client is DNSBL listed.

Related RFCs:

[1918] Address Allocation for Private Internets
[2821] Simple Mail Transfer Protocol (Sect 3.6 and Sect 5)

@client_ip_eq_helo_score (1.5, -1.25)

Define scores for the match of the reverse record (hostname) against the HELO argument. Reverse lookups are done, if the forward lookups failed and are not trusted.

Log Entries:

REV_IP_EQ_HELO
The Client's PTR matched the HELO argument.

REV_IP_EQ_HELO_DOMAIN
Domain portions of Client PTR and HELO argument matched.

RESOLVED_IP_IS_NOT_HELO
Client PTRs found but did not match HELO argument.

@helo_score (1.5, -2)

Define scores for the match of the Client IP and its /24 subnet against the A records of HELO or MAIL FROM domain/host. It also holds the bad score for MX verifications.

Log Entries:

CL_IP_EQ_HELO_NUMERIC
Client IP matches the [IPv4] HELO.

CL_IP_EQ_FROM_IP
Client IP matches the A record of the MAIL FROM sender domain/host.

CL_IP_EQ_HELO_IP
Client IP matches the A record of the HELO argument.

CL_IP_NE_HELO
The IP and the /24 subnet did not match A/MX records of HELO and MAIL FROM arguments and their subdomains.

@helo_from_mx_eq_ip_score (1.5, -3.1)

Define scores for the match of Client IP against MX records. Positive (SPAM) values are used in case the MAIL FROM matches not the HELO argument AND the client seems to be dynamic AND the client is no MX for HELO and MAIL FROM arguments. The total DNSBL score is added to its bad score.

Log Entries:

CL_IP_EQ_FROM_MX
Client IP matches the MAIL FROM domain/host MX record

CL_IP_EQ_HELO_MX
Client IP matches the HELO domain/host MX record

CLIENT_NOT_MX/A_FROM_DOMAIN
Client is not a verified HELO and doesn't match A/MX records of MAIL FROM argument

CLIENT/24_NOT_MX/A_FROM_DOMAIN
Client's subnet does not match A/MX records of the MAIL FROM argument

$dnsbl_checks_only (default: 0)

Disable HELO/RHSBL verifications and the like. Do only RBL checks.
1 = on, 0 = off

@dnsbl_score (default: see below)

A list of RBLs to be checked. If you want that a host is not being evaluated any further if it is listed on several lists or a very trustworthy list you can control a immediate REJECT with $MAXDNSBLHITS and/or $MAXDNSBLSCORE. A list of RBLs must be build as follows:

@dnsbl_score = (
RBLHOST1, HIT SCORE, MISS SCORE, LOG NAME,
RBLHOST2, HIT SCORE, MISS SCORE, LOG NAME,
...
);
The default is:

@dnsbl_score = (
"pbl.spamhaus.org", 3.25, 0, "DYN_PBL_SPAMHAUS",
"sbl-xbl.spamhaus.org", 4.35, -1.5, "SBL_XBL_SPAMHAUS",
"bl.spamcop.net", 3.75, -1.5, "SPAMCOP",
"ix.dnsbl.manitu.net", 4.35, 0, "IX_MANITU"
);

@rhsbl_score (default: see below)

Define a list of RHSBL host which are queried for the sender domain. Results get additionally scores of 0.5 * DNSBL results and @rhsbl_penalty_score. A list of RHSBL hosts to be queried must be build as follows:

@rhsbl_score = (
RHSBLHOST1, HIT SCORE, MISS SCORE, LOG NAME,
RHSBLHOST2, HIT SCORE, MISS SCORE, LOG NAME,
...
);
The default is:

@rhsbl_score = (
"multi.surbl.org", 4, 0, "SURBL"
);

@rhsbl_penalty_score (3.1, 0)

This score will be added to each RHSBL hit if following criteria are met:

Sender has a random local-part (i.e. yztrzgb@example.tld)

or MX records of sender domain are bogus

or FROM matches not HELO

or HELO is untrusted (Forward record matched, reverse record
did not match)

$MAXDNSBLHITS (default: 2)

If the client is listed in more than $MAXDNSBLHITS RBLs it will be rejected immediately with $MAXDNSBLMSG and without further evaluation. Results are cached by default.

$MAXDNSBLSCORE (default: 8)

If the BAD SCOREs of @dnsbl_score listed RBLs reach a level greater than $MAXDNSBLSCORE the client will be rejected immediately with $MAXDNSBLMSG and without further evaluation. Results are cached by default.

$REJECTLEVEL (default: 1)

Score results equal or greater than this level will be rejected with $REJECTMSG

LICENSE

GNU General Public License

AUTHOR

Robert Felber <r.felber@ek-muc.de>
Autohaus Erich Kuttendreier
81827 Munich, Germany