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greylist.conf(5)					      greylist.conf(5)

NAME
       greylist.conf - milter-greylist configuration file

DESCRIPTION
       greylist.conf  configures  milter-greylist(8)  operation. The format is
       simple: each line contains a keyword and	optional arguments.  Any  line
       starting	 with  a  #  is	 considered as a comment and is	ignored. Blank
       lines are ignored as well. Comments at the end of lines are accepted in
       some  situations,  but do not take them as granted.  A statement	can be
       continued on the	next line by using a  backslash.  Anything  after  the
       backslash will be ignored.

WHITELIST
       The  primary  use  of  greylist.conf  is	 to  setup  milter-greylist(8)
       whitelist. It also offers  a  handy  blacklist  feature.	  Access-lists
       (ACL) are used to do that. ACL enable the administrator to specify com-
       plex conditions on sender IP, sender DNS	 address,  sender  e-mail  ad-
       dress,  and  recipient e-mail address. If support for DNSRBL was	built-
       in, it is even possible to use DNSRBL in	ACL.

       An access-list entry starts with	the racl keyword followed  by  an  op-
       tional  id  quoted  string, then	the greylist, whitelist, blacklist, or
       continue	keyword, and by	any set	of the following  clauses:  addr,  do-
       main,  from, rawfrom, rcpt, rcptcount, helo, sm_macro, time, auth, tls,
       spf (if build with SPF support),	geoip (if build	with  GeoIP  support),
       p0f (if build with p0f support),	ldapcheck (if build with --with-openl-
       dap), urlcheck (if built	with --with-libcurl), dnsrbl  (if  built  with
       --enable-dnsrbl),  and  nsupdate	(if supported by the DNS resolver).  A
       message will match an ACL entry	when  it  complies  with  all  of  its
       clauses.

       The  greylist, whitelist, and blacklist keywords	will cause the message
       to be respectively greylisted, accepted or rejected if all ACL  clauses
       match,  and ACL evaluation is terminated	there. If an ACL with continue
       keyword does match, nothing is decided and next ACL are evaluated.

       Clauses can be negated, by prefixing them by the	not keyword.  Here  is
       the detail of all possible clauses.

       addr   This  clause  is	used  to  specify  a netblock of source	IP ad-
	      dresses. The syntax is an	IP address followed by a slash	and  a
	      CIDR netmask. Here is an example:

		racl whitelist addr 127.0.0.0/8
		racl whitelist addr 192.168.3.0/24
		racl whitelist addr ::1

	      If  the  netmask	is omitted, /32	is assumed for an IPv4 address
	      and /128 is assumed for an IPv6 address.

	      You should at least whitelist localhost  (127.0.0.1/8),  and  if
	      you have some user clients connecting to the machine, you	should
	      whitelist	the addresses they connect from	if you don't want them
	      to get error messages when sending e-mail.

       domain This  clause  selects  source  machines based on their DNS name,
	      performing a suffix search.  For instance, this  will  whitelist
	      any machine in the example.net domain:

		racl whitelist domain example.net

	      Suffix  search  matching	 means,	for example, that gle.com will
	      match google.com.	If you want domain names to match on subdomain
	      boundaries  (e.g.	  gle.com  will	match mail.gle.com and gle.com
	      but not google.com) then enable domainexact

       The name	resolution is made by Sendmail,	 which	hands  it  to  milter-
       greylist(8).  As	a result, it is	impossible to use DNS aliases here. On
       the other hand, this will work even if your DNS resolver	is not thread-
       safe.

       from   This  is	used  to select	sender e-mail addresses	You should not
	      use that feature,	because	sender e-mail addresses	can  be	 triv-
	      ially forged.

	      Please  note  that  the sender e-mail is cleared from spaces and
	      anything leading an equal	(=) sign so that mailing-lists return-
	      address  with  unique return paths can still match.  If you need
	      unedited sender address, use a rawfrom clause.

	      Here is an example:

		racl whitelist from postmaster@example.com

       rawfrom
	      Same as from but the sender e-mail address is  not  modified  to
	      stip anything.  rcpt This	is used	to select recipient addresses.
	      Example:

		racl greylist rcpt John.Doe@example.net

       rcptcount
	      Followed by an operator and a recipient count, this is  used  to
	      select the amount	of recipients. Example:

		racl  blacklist	 rcptcount  >= 25 msg "No more than 25 recipi-
	      ents, please"

       helo   Followed by a quoted string or a regular expression, this	can be
	      used to filter on	the HELO string.

       sm_macro
	      This  is	used to	select a Sendmail macro	value. See the section
	      on that topic for	more information.

       time   This is used to specify a	time set. It should be followed	 by  a
	      quoted  string of	crontab(5)-like	time specification. Here is an
	      example that whitelists mail addressed  to  a  single  recipient
	      during office hours (from	8:00 to	16:59 from monday to friday):

		racl whitelist time "* 8-16 * *	1-5" rcpt info@example.net

       geoip  This  is	used  to  specify a country, as	reported by GeoIP. The
	      country code must	be upper case, and is only available  if  mil-
	      ter-greylist  was	built with GeoIP support. Special country code
	      ZZ is used when the country cannot be determined	(this  happens
	      for  private addresses, for instance). The geoipdb statement can
	      be used to specify the location of  GeoIP	 database.   geoipv6db
	      statement	 can  be used to specify the location of GeoIPv6 data-
	      base.

       p0f    This is used to match against the	remote system  OS  fingerprint
	      genre and	detail,obtained	from p0f. It is	only available if mil-
	      ter-greylist was built with p0f support.	 p0f  clauses  can  be
	      used  with a quoted string for case-insensitive substring	match,
	      or against regular expressions. The  p0fsock  statement  can  be
	      used to specify the location of the p0f socket.

       auth   This is used to select a user that succeeded SMTP	AUTH. In order
	      to select	any user that succeeds SMTP AUTH, you can use a	 regu-
	      lar expression matching, like below;

		racl whitelist auth /.*/

	      Using  such  a  clause automatically disable global STARTTLS and
	      SMTP AUTH	whitelisting, like if the noauth  keyword  would  have
	      been used.

       tls    This  is	used  to  select the distinguished name	(DN) of	a user
	      that succeeded STARTTLS. Using such a clause automatically  dis-
	      able  global  STARTTLS  and  SMTP	AUTH whitelisting, like	if the
	      noauth keyword would have	been used.

       spf    This is used to test SPF status. Possible	values are pass, soft-
	      fail,  fail, neutral, unknown, error, none, and self.  The first
	      seven values are plain SPF validation status. The	self value  is
	      a	special	test that checks the server's local IP address against
	      the sender's SPF record. If that test validates, odds  are  good
	      that  the	 sender	SPF record is wide open, and this is hint that
	      SPF should not be	trusted.

	      In order to use spf self,	Postfix	users must specify  the	 local
	      address in the configuration file, using the localaddr option.

	      Absence  of any value after the spf keyword is a synonym for spf
	      pass.  This is present for backward compatibility.

	      The spf clause is	only available if SPF support was compiled in.
	      Using it will disable global SPF whitelisting, like if the nospf
	      keyword would have been used.

       ldapcheck
	      This is used to query an LDAP directory.	 See  the  section  on
	      that topic for more information.

       urlcheck
	      This  is	used to	query an external configuration	source through
	      an URL.  See the section on that topic for more information.

       dnsrbl This is used to select a DNSRBL. See the section on  that	 topic
	      for more information.

       nsupdate
	      This  always-matching clause performs a DNS update, see the sec-
	      tion on that topic for more information.

       The domain, from, and rcpt clauses may be  used	with  regular  expres-
       sions.  The regular expressions must be enclosed	by slashes (/).	No es-
       caping is available to provide a	slash inside a regular expression,  so
       just  do	not use	it. Regular expressions	follow the format described in
       re_format(7).  Here is an example:

	 racl greylist rcpt /@example\.net$/

       When regular expressions	are not	used, from, and	rcpt  perform  a  case
       insensitive  substring match with leading and trailing brackets,	spaces
       and tabs	stripped out.	domain	performs  a  case  insensitive	suffix
       match.  This means, for example,	that gle.com will match	google.com. If
       you want	domain names to	match on subdomain boundaries  (e.g.   gle.com
       will match mail.gle.com and gle.com but not google.com) then enable do-
       mainexact

       An ACL entry can	also hold various optional parameter  used  on	match:
       delay,  autowhite,  flushaddr, nolog, code, ecode, report, maxpeek, ad-
       dheader,	addfooter, and msg

       delay  Specify the greylisting delay used before	the message can	be ac-
	      cepted.  This overrides the greylist global setting, and it only
	      makes sense on an	racl greylist entry.

       autowhite
	      Specify the autowhitelisting duration for	messages matching this
	      ACL.   This  overrides the autowhite global setting, and it only
	      makes sense on an	racl greylist entry. Example:

		racl greylist rcpt JDoe@example.net delay 15m autowhite	3d
		racl greylist rcpt root@example.net delay 1h autowhite 3d

       flushaddr
	      If a message matches the rule, any entry in the greylist or  au-
	      towhite databases	matching the sender IP is removed. Used	with a
	      DNSRBL blacklist ACL, it is useful for freeing the database from
	      entries  set up by a machine which is known to be	a spammer. Ex-
	      ample:

		racl blacklist dnsrbl "known-spammer" flushaddr

       nolog  Do not generate syslog message if	this rule matches. Example:

		racl whitelist default nolog

       code

       ecode

       msg    These 3 values can be used to choose  the	 SMTP  code,  extended
	      code and reply message for temporary failures and	rejects. Exam-
	      ple:

		racl blacklist dnsrbl "spamstomp" msg "IP caught by spamstomp"
		racl greylist default code "451" ecode "4.7.1"

	      The msg strings accepts format string substitution as documented
	      in the FORMAT STRINGS section. For instance, %A gets substituted
	      by the ACL line number.

	      None of the last 3 values	makes sense for	a whitelist entry.

       report This value  overrides  the  text	displayed  in  the  X-Greylist
	      header,  for messages that milter-greylist(8) lets pass through,
	      either because they are  whitelisted,  or	 because  they	passed
	      greylisting  (see	REPORTING).  This string can be	substituted as
	      documented in the	FORMAT STRINGS section.

       maxpeek
	      This parameter only makes	sense in a RCPT-stage  ACL.  It	 over-
	      rides  the global	maxpeek	setting	for DATA-stage handling	of the
	      message. It has no effect	if global maxpeek is set to 0.

       addheader
	      This quoted string is a RFC822 header that  gets	added  to  the
	      message.	 Format	 string	substitution is	supported. No check is
	      done for header length standard compliance,  so  make  sure  the
	      substituted  string is shorter than 2048 characters. Headers are
	      appended to the bottom, unless an	optionnal comma-separated pos-
	      itive  index  is specified after the quoted string; in this case
	      the header will be inserted at this index	point  from  the  top.
	      Here is an example:
	      racl continue addheader "X-Personnal-Header: Hello world!",1

       addfooter
	      Append  a	 footer	to the message.	Usual escape sequences such as
	      \n can be	used to	get special characters.	The string is  subject
	      to  format  string  expantion as described in the	FORMAT STRINGS
	      section. The footer will not be append  if  milter-greylist  was
	      not able to capture the whole message, therefore maxpeek must be
	      set approriately.

       Entries in the access-list are evaluated	sequentially, so order is very
       important. The first matching entry is used to decide if	a message will
       be whitelisted or greylisted. A special default clause can be  used  in
       the  last  ACL  entry as	a wildcard.  Here are a	few complete ACL exam-
       ples:

       Example 1:

       racl whitelist from friend@toto.com rcpt	grandma@example.com
       racl whitelist from other.friend@example.net rcpt grandma@example.com
       racl greylist rcpt grandma@example.com
       racl whitelist default

       Example 2:

       racl whitelist addr 193.54.0.0/16 domain	friendly.com
       racl greylist rcpt user1@atmine.com
       racl greylist rcpt user2@atmine.com
       racl greylist rcpt user3@atmine.com
       racl whitelist default

       Example 3:

       racl whitelist rcpt /@.*otherdomain\.org$/
       racl whitelist addr 192.168.42.0/24 rcpt	user1@mydomain.org
       racl whitelist from friend@example.net rcpt /@.*mydomain\.org$/
       racl whitelist rcpt user2@mydomain.org
       racl greylist rcpt /@.*mydomain\.org$/
       racl whitelist default

DATA-STAGE ACL
       ACL using the racl keyword are evaluated	at the RCPT stage of the  SMTP
       transaction.  It	 is  also  possible  to	have ACL evaluated at the DATA
       stage of	the SMTP transaction, using the	 dacl  keyword,	 provided  the
       message	went  through  RCPT-stage  ACL,	and possibly greylisting. Note
       that you	cannot use the greylist	action at DATA-stage if	the RCPT-stage
       ACL  that  matched  had a greylist action itself. The following clauses
       can be used to work on message content:

       dkim   DKIM status (if build with DKIM support).	 Possible  values  are
	      pass, fail, unknown, error, and none,

       header String or	regular	expression searched in message headers

       body   String or	regular	expression searched in message body

       msgsize
	      Operator	followed  by a message size (k or M suffix allowed for
	      kilobytes	or megabytes). Example:

		dacl blacklist msgsize >= 4M msg "No more than 4 MB please"

       spamd  SpamAssassin score (if build with	SpamAssassin support). If used
	      without  comparison operator spamd is true if the	score is above
	      threshold. The spamdsock keyword can be used to specify the  lo-
	      cation of	the spamd socket.

	      Example 1:

		spamdsock unix "/var/spamassassin/spamd.sock"
		racl whitelist default
		dacl greylist spamd

	      Example 2:

		spamdsock inet "127.0.0.1:783"
		racl whitelist default
		dacl blacklist spamd > 15 msg "Your message is considered spam."
		dacl greylist  spamd > 10 delay	2h
		dacl greylist  spamd > 5  delay	1h

       Note  that if there are multiple	recipient, a rcpt clause at DATA stage
       evaluates to true if it matches any of them.  If	you want to  match  an
       exact set of recipients,	you can	use multiple rcpt clauses along	with a
       rcptcount clause.

LISTS
       It is often useful to group several users or sender IP addresses	 in  a
       single  ACL.  This  can be done with lists. Lists must be first defined
       and given a name	before they can	be used	in ACL entries.	Here is	an ex-
       ample:

		list "my users"	rcpt { user1@example.com user2@example.com }
		list "local" addr { 192.0.2.0/24 10.0.0.0/8 }

		racl whitelist list "local"
		racl greylist list "my users"
		racl whitelist default

BACKWARD COMPATIBILITY
       Previous	 versions  of  milter-greylist(8) used addr, domain, from, and
       rcpt lines, without the racl keyword.  Access-list  management  is  in-
       tended  to  replace  them.   These  lines are still accepted by milter-
       greylist(8), but	they are deprecated.  milter-greylist(8) handles  them
       as access-list entries with a single clause. They are added at the head
       of the access-list so the use of	these keywords	and  access-lists  may
       lead to unspecified behaviour. Do not mix them.

       test  mode  (using -T) is also deprecated. Access-list semantics	do not
       depend on this flag.

       milter-greylist(8) also used to only have a RCPT-stage ACL,  which  was
       configured  through  acl	 statements.  These have been replaced by racl
       statements (as opposed to dacl statements  for  DATA-stage  ACL).   acl
       statements are still accepted for backward compatibility	and are	a syn-
       onym for	racl statements.

MX SYNC
       Synchronization of the greylist among multiple MX is  configured	 using
       the  peer  keyword. List	each other MX IP addresses using the peer key-
       word. Here is an	example:

	 peer 192.0.2.18
	 peer 192.0.2.17
	 peer 192.0.2.22 timeout 7
	 peer 192.0.2.38 timeout 5m

       You can list the	local machine in the peer statements, it will  be  ig-
       nored.

       The timeout clause sets a peer communication timeout to have proper re-
       trial in	case of	slow MX	peer. The default value	is 3 seconds. The spe-
       cial value of 0 disables	the connection retrials.

       By  default,  milter-greylist  will  listen on all interfaces using TCP
       port 5252 or the	port number given by service named mxglsync if defined
       in  /etc/services  or  other  directory	service. This behaviour	can be
       changed by using	the syncaddr keyword. Here are a few examples:

	 syncaddr *
	 syncaddr * port 7689
	 syncaddr 192.0.2.2 port 9785
	 syncaddr 2001:db8::1:c3b5:123
	 syncaddr 2001:db8::1:c3b5:123 port 1234

       Using '*' as the	address	means to bind to  all  local  interfaces'  ad-
       dresses.	 Note that if you are not using	the default port, all MXs must
       use the same port number.

       For outbound connections	the system is selecting	one  of	 the  possible
       addresses.  If you want to use a	specific IP you	can use:

	 syncsrcaddr 123.456.78.9

TEXT DUMP
       milter-greylist(8) uses a text dump of its database to resume operation
       after a crash. The dump is performed at regular time interval,  but  as
       it  is a	heavy operation, you might want	to configure a particular time
       interval, using the dumpfreq option.

       If the dumpfreq value is	too small, it will kill	performance. If	it  is
       too high, you will loose	a bigger part of the database on a crash.

       Set dumpfreq to 0 to get	a dump on each change (kills performance), Set
       it to -1	to never dump to a file	(unsafe	as you lose the	whole greylist
       on  each	crash),	or give	a time value for the delay between dumps.  The
       time is given in	seconds, except	if a unit is given: m for  minutes,  h
       for hours, and d	for days.

       You  may	 further  improve the performance of the dump operation	at the
       expense of humanly readable timestamp which by  default	appears	 as  a
       comment at the end of each line in the dumpfile.	You may	disable	gener-
       ation of	this comment by	specifying dump_no_time_translation option  in
       the  configuration file.	This is	specifically recommended if your dump-
       file grows to 100's of megabytes	- it can reduce	the  time  needed  for
       the dump	operation by the order of magnitude!

REPORTING
       By default, milter-greylist(8) will add a X-Greylist header to any mes-
       sage it handles.	The header shows what happened to the message: delayed
       or  not	delayed,  and  why.  The  following  options  can  be  used in
       greylist.conf to	alter this behavior:

       report none
	      Never add	a X-Greylist header.

       report delays
	      Only add a header	if the message was delayed.

       report nodelays
	      Add a header if the message was not delayed. The header explains
	      why the message was not delayed.

       report all
	      Always add a header. This	is the default.

SENDER CALLBACK	SYSTEMS
       Sender  callback	systems	are another anti-spam measure that attempts to
       send a DSN to the sender	address	before accepting a  message.  If  that
       fails,  then  the  sender address is wrong and the message is rejected.
       Such systems usually stop their callback	check at the RCPT stage	of the
       SMTP transaction.

       Greylisting  temporarily	 rejects at the	RCPT stage, so sender callback
       and greylisting love to fight each other.  milter-greylist(8)  proposes
       a  workaround  to  that problem with the	delayedreject option. For mes-
       sages coming from <> (that is, for DSN),	it will	 cause	the  temporary
       reject  to  happen at the DATA stage of the SMTP	transaction instead of
       the RCPT	stage. That way, milter-greylist(8) will cope much better with
       sender callback systems.

       This  has  a  minor  drawback (and this is why it is not	enabled	by de-
       fault): for a multi recipient DSN, whitelisted recipient	 will  not  be
       honoured: the message will be delayed for everyone.

SENDMAIL MACROS
       Any sendmail macro can be used as a clause in the access	list. You need
       to define a (macro, value) pair using the sm_macro keyword before using
       it.  Here is an example that uses the {client_resolve} macro to apply a
       larger greylisting delay	to hosts that have a bogus reverse DNS:

		sm_macro "maybe_forged"	"{client_resolve}" "FORGED"

		racl greylist sm_macro "maybe_forged" delay 1h
		racl greylist default delay 15m

       A regular expression can	be used	as the macro value.  It	must  be  sur-
       rounded	with  slashes  and not by quotes.  The special value unset can
       also be used to match an	unset macro:

		sm_macro "not_foo" "{foo}" unset

       Note that any Sendmail macro  that  is  not  exported  using  the  Mil-
       ter.macros.envrcpt  setting  of	sendmail.cf will be seen as unset from
       milter-greylist.

DNSRBL
       DNS Reverse Black List can be used to toggle an ACL. They must  be  de-
       fined  and named	before they can	be used. Here is an example which uses
       a bigger	greylisting delay for hosts caught in the SORBS	 dynamic  pool
       DNRSBL (this will include DSL and cable customers pools,	which are well
       known to	be massively infected by spamwares):

		dnsrbl "SORBS DUN" dnsbl.sorbs.net 127.0.0.10/32

		racl greylist dnsrbl "SORBS DUN" delay 1h
		racl greylist default delay 15m

       The definition of a DNSRBL starts by the	dnsrbl	keyword,  followed  by
       the quoted name of the DNSRBL, the DNS domain on	which addresses	should
       be looked up, and the answer we should consider as a positive hit.

       DNSRBL support is only available	if enabled through the --enable-dnsrbl
       config  flag.  Please  make sure	milter-greylist(8) is linked against a
       thread-safe DNS resolver, otherwise it shall crash.

DNS updates
       ACL are able to trigger a DNS update, which  can	 be  used  to  feed  a
       DNSRBL.	 That  functionnality  is enabled at build time	if the DNS re-
       solver has DNS update support.

       Configuration is	done with the nsupdate statement, which	 may  be  used
       several times, and the optionnal	tsig statement,	if you want ot use au-
       thenticated DNS update. Here is an example syntax:

		tsig "dns-update" "hmac-md5" "1B2M2Y8AsgTpgAmY7PhCfg=="
		nsupdate "bl.example.net" { rname  "%j.bl.example.net"	rvalue
	      "127.0.0.2" tsig "dns-update" }

       The options for nsupdate	are:

       rname  Created record name, which uses format strings.

       rvalue Created record value, which uses format strings.

       servers
	      Quoted  comma-separated  list of DNS server the update should be
	      sent to.	Default	is to use the  system  confifugration,	usualy
	      from /etc/resolv.conf

       ttl    TTL of created DNS record. Default is 0 seconds.

       class  Created  record  class,  as  numeric value. Default is 1,	for IN
	      class.

       type   Created record type, as numeric value. Default is	1, for A type.

       tsig   The name of a tsig configuration,	which must have	been  supplied
	      before.  If  unspecified,	 unauthenticated  DNS updates are per-
	      formed.

       Once configured,	DNS updates can	be used	in any ACL:

		racl blacklist rcpt  spamtrap@example.net  nsupdate  "bl.exam-
	      ple.net"

PROPERTIES
       Properties are variables	that can be set, evaluated and printed in ACL.
       A property may be dropped once the current recipient is	processed,  or
       it  can be retained until the message is	processed. They	can be created
       through the following always-matching ACL clauses:

       set $name="value"
	      This sets	a property that	will be	retained for all next  recipi-
	      ents.  Right  hand  side	of  the	 clause	may be a quoted	string
	      (which will be substituted using format strings, as described in
	      the  FORMAT STRINGS section), a number, or another property name
	      (which will be substituted by the	property value).

       rset $name="value"
	      Same as set clause, except that the property will	be droped once
	      the current user will have been processed.

       urlcheck
	      These  clause will cause properties to be	fetched	from an	exter-
	      nal web service.	See the	URL checks section below for details.

       ldapcheck
	      These clause will	cause properties to be fetched from a LDAP di-
	      rectory See the LDAP CHECKS section below	for details.

       Properties can be used as left-hand side	part of	ACL clauses:

		racl blacklist $name "badvalue"
		racl blacklist $name /badregex/

       If  used	 left-hand  side  and prefixed by a star, the property will be
       evaluated as a glob(7) pattern, In the example below, if	sender DNS do-
       main is test.example.net	and $domain is *.example.net, we get a match.

		racl blacklist *$domain	"%f"

       They are	also available as right-hand side of many ACL clauses:

		racl continue set $badword="spam"
		racl blacklist body $badword

       Values  of properties can be obtained in	any quoted string that is sub-
       ject to format string expantion:

		racl continue set $webmaster="webmaster@example.net"
		racl blacklist domain evil.net msg "blacklisted,  ask  $P{web-
	      master} why"

       When  the  property value is a number, it can be	increased or decreased
       using this syntax:

		racl continue set $score+=5
		racl continue set $score-=5

       Here again, right hand side may be a quoted string, a number or another
       property.  For  the  quoted  string and property	cases, a conversion is
       first made to an	integer, using 0 as a value on failure.	Note  that  no
       arithmetic  evaluation  occurs. For instance, the quoted	string "1 + 1"
       will be evaluated as 0.

       The log ACL clause can be helpful when one need to figure what  happens
       to  property  values during the ACL flow. See the CUSTOM	REPORT section
       for more	details.

URL checks
       milter-greylist(8) is able to query  external  sources  of  information
       through	various	 URL,  if it was built with --with-libcurl. Here is an
       example:

		urlcheck "glusr" "http://www.example.net/mgl-config?rcpt=%r" 5

		racl greylist urlcheck "glusr" delay 15m
		racl whitelist default

       The trailing 5 at the end of the	urlcheck  definition  is  the  maximum
       number  of  simultaneous	connections we want to launch on this URL. For
       each message, the URL will be queried, with  % format tags  being  sub-
       stituted.  For  instance,  %r  is substituted by	the recipient. See the
       FORMAT STRINGS section for the complete list of substitutions.

       milter-greylist(8) expects an answer containing a list of \n terminated
       lines, with key:	value pairs. The most basic answer to get a match is:

		milterGreylistStatus: Ok

       TRUE can	be used	as an alias for	Ok here.

       The  answer  can	 be more complex, with keys that will overload the ACL
       settings:

       milterGreylistDelay
	      The greylisting delay to use (time unit suffix allowed).

       milterGreylistAutowhite
	      The autowhite delay to use (time unit suffix allowed).

       milterGreylistFlushAddr
	      The value	is ignored. If this key	is present, then  the  IP  ad-
	      dress  for  the sender machine will be flushed from greylist and
	      autowhite	databases.

       milterGreylistCode
	      The SMTP code to return (e.g.: 551).

       milterGreylistECode
	      The SMTP extended	code to	return (e.g.: 5.7.1)

       milterGreylistMsg
	      The string to return with	SMTP codes.

       milterGreylistReport
	      The string to display in the X-Greylist header.

       milterGreylistIgnore
	      This line	will be	ignored, without warnings in the logs.

       milterGreylistAction
	      This feature is nifty but	use it with caution, as	it  makes  the
	      access  list  a  bit  difficult to understand. By	specifying the
	      values greylist, whitelist, or  blacklist,  it  is  possible  to
	      overload the ACL action itself.

       The ACL will match if any of the	above key is returned: milterGreylist-
       Status is not mandatory.

       Optional	keywords can be	appended to a urlcheck definition:

       postmsg
	      On DATA-stage ACL, This causes the message to  be	 sent  (up  to
	      maxpeek bytes) in	a POST request.	Here is	an example:

		urlcheck "extfilter" "http://www.example.net/f.cgi" 5 postmsg

		dacl blacklist urlcheck	"extfilter"
		dacl whitelist default

       getprop
	      Gather  the properties returned by the URL and reuse them	in the
	      ACL.  The	gathered properties can	be accessed in the current and
	      following	ACL by prefixing them by a dollar ($).

       clear  This causes gathered properties to be cleared on each new	recip-
	      ient.  This avoids properties for	several	recipients to mix.

       fork   Tells milter-greylist(8) to fork a separate instance  of	itself
	      for  performing  the  queries.  Use  it if you encounter thread-
	      safety problems.	fork is	not compatible with postmsg.

       domatch
	      Cause the	ldapcheck clause to be evaluated in ACL.  Default  be-
	      havior is	to ignore the result and just fecth properties,	except
	      if the LDAP directory is unreachecable, in which case  a	tempo-
	      rary failure occurs.  The	fixldapcheck gloabal settings may also
	      be used to globaly cause all ldapcheck and urlcheck  clauses  to
	      match.

       Here  is	an example that	will use various DNSRBL	depending on a per-re-
       cipient setting stored in the dnsrbl attribute of a LDAP	directory.

		dnsrbl "RBL2" "rbl.example.net"	"127.0.0.2"
		dnsrbl "RBL3" "rbl.example.net"	"127.0.0.3"
		dnsrbl "RBL4" "rbl.example.net"	"127.0.0.4"
		urlcheck  "userconf"  "ldap://localhost/dc=example,dc=net?mil-
	      terGreylistStatus,dnsrbl?one?mail=%r" 5 getprop clear

		racl  blacklist	 urlcheck  "userconf"  $dnsrbl	"RBL2"	dnsrbl
	      "RBL2"
		racl blacklist $dnsrbl "RBL3" dnsrbl "RBL3"
		racl blacklist $dnsrbl "RBL4" dnsrbl "RBL4"

       Note that when matching gathered	properties, format strings  and	 regex
       can be used.

LDAP CHECKS
       If  milter-greylist  was	 built with --with-openldap, then you can also
       use ldapcheck for pulling information  from  an	LDAP  directory.  This
       works  exactly  like  urlcheck,	except that properties are always col-
       lected: The getprop option is implicit.

       A list of LDAP URL to use can be	specified with the  ldapconf  keyword.
       The network timeout is optional.

		ldapconf  "ldap://localhost  ldaps://ldap.example.net" timeout
	      2s

       When ldaps:// is	used, the system's ldap.conf file is  used  to	locate
       x509 certificates.

       When  defining LDAP queries with	the ldapcheck statement, note that the
       scheme and host part of the URL are ignored.  Servers listed  in	 ldap-
       conf are	used instead.

RATE LIMIT
       The ratelimit keyword specifies a ratelimit configuration to be used in
       access lists. It	must be	followed by the	rate limit configuration name,
       what  is	being accounted	(i.e.: session for SMTP	sessions, rcpt for re-
       cipients, data for bytes	in body	and headers), the  actual  limit,  and
       the sampling period. Example:

		ratelimit "internalclients" rcpt 10 / 1m

		racl blacklist addr 192.0.2.0/24 ratelimit "internalclients" \
		   msg "you speak too much"

       The ratelimit keyword can also have an option key statement, which  de-
       termine	the  set  of key for message accounting. The default is	%i for
       per IP address accounting (see the FORMAT STRINGS sections for the pos-
       sible  syntax of	this field). Here is an	example	that configures	a rate
       limit of	100 messages per hour for each individual recipient-IP set.

		ratelimit "internalclients" rcpt 100 / 1h key "%r%i"

		racl blacklist addr 192.0.2.0/24 ratelimit "internalclients" \
		   msg "you speak too much"

CUSTOM REPORTS
       The  stat  keyword  can	be used	to specify a custom report for milter-
       greylist	activity.  It should be	supplied with an output	 (either  file
       or external command) and	a format string. Here is an example:

		stat ">>/var/log/milter-greylist.log" "%T{%T},%i,%f,%r,%A\n"

       If  the output starts by	__ or _	then it	is a file. Use __ to append to
       an existing file, and use _ to overwrite	it. If the output starts by  a
       | then the output is a shell command, like in the example below:

		stat "|logger -p local7.info" "%T{%T},%i,%f,%r,%A\n"

       The format string gets substituted as URL checks	format string: %r gets
       substituted by the recipient, %f	by the sender, and so on. See the FOR-
       MAT STRINGS section for a complete list of available substitutions.

       There  is  also	an  always-matching log	ACL clause that	can be used to
       send a formated string to syslog	with LOG_INFO level.  Here is an exam-
       ple:

	      racl continue rcpt /@example\.com$/ log "I was here"

COMMAND-LINE FLAG EQUIVALENTS
       Most  milter-greylist(8)	 command-line  options have equivalent options
       that can	be set in the configuration file. Note that if a command  line
       option is supplied, it will always override the configuration file.

       If  a  command-line equivalent keyword is used more than	once, the last
       keyword will override the previous ones.

       verbose
	      Enable debug output. This	is equivalent to the -v	flag.

       quiet  Do not tell clients how much time	remains	 before	 their	e-mail
	      will be accepted.	This is	equivalent to the -q flag.

       nodetach
	      Do  not  fork  and go into the background. This is equivalent to
	      the -D flag.

       noauth Greylist clients regardless  if  they  succeeded	SMTP  AUTH  or
	      STARTTLS.	 Equivalent to the -A flag.

       noaccessdb
	      Normally	milter-greylist(8)  will  whitelist a message if send-
	      mail(8) defines a	${greylist} macro set to WHITE.	 This  enables
	      complex whitelisting rules based on the Sendmail access DB. This
	      option inhibits this behavior.

       nospf  Greylist clients regardless if they are  SPF-compliant.  Equiva-
	      lent to the -S flag.

       testmode
	      Enable test mode.	Equivalent to the -T flag. This	option is dep-
	      recated.

       greylist
	      The argument sets	how much time milter-greylist(8) will want the
	      client  to  wait between the first attempt and the time the mes-
	      sage is accepted.	The time is given in seconds, except if	a unit
	      is  given:  m  for  minutes,  h  for hours, and d	for days.  The
	      greylist keyword is equivalent to	the -w option. Here is an  ex-
	      ample that sets the delay	to 45 minutes:

		greylist 45m

       autowhite
	      This  sets  the auto-whitelisting	duration, equivalent to	the -a
	      command-line option. As for the greylist keyword,	units  can  be
	      supplied.	Here is	an example for a 3 day long auto-whitelisting:

		autowhite 3d

       pidfile
	      This  causes  milter-greylist(8)	to write its PID into the file
	      given as argument, like the -P command line argument  does.  The
	      path  to	the  file  must	be absolute and	it must	be enclosed in
	      quotes. Here is an example:

		pidfile	"/var/run/greylist.pid"

       dumpfile
	      This chooses the location	of the greylist	dump file, like	the -d
	      command line option does.	The path must be absolute and enclosed
	      in quotes.  It can optionally be followed	by an octal permission
	      mode.  Example:

		dumpfile "/var/milter-greylist/greylist.db" 640

       subnetmatch
	      This  is	equivalent  to	the -L command line option. It takes a
	      slash followed by	a CIDR mask as argument, and it	 commands  the
	      subnet matching feature. Example,	for a class C wide matching:

		subnetmatch /24

       subnetmatch6
	      This  is	equivalent  to	the -M command line option. It takes a
	      slash followed by	a prefixlen as argument, and it	 commands  the
	      subnet matching feature. Example,	for a subnet wide matching:

		subnetmatch6 /64

       socket Like the -p command line option, this keyword is used to specify
	      the socket used to communicate with sendmail(8).	It must	be en-
	      closed in	quotes and can optionally be followed by an octal per-
	      mission mode (valid values are 666, 660  or  600,	 other	values
	      cause an error):

		socket "/var/milter-greylist/milter-greylist.sock" 660

       user   This  keyword  should be followed	by a quoted user login and op-
	      tionally a colon followed	by a groupname.	 Like the  -u  option,
	      this is used to run milter-greylist(8) as	a non root user.  Here
	      is an example:

		user "smmsp"

MISCELLANEOUS
       These options have no command line equivalent:

       logfac Sets the syslog facility for messages.  Can be set to any	of the
	      standard	facilities:  kern,  user,  mail, daemon, auth, syslog,
	      lpr, news, uucp, cron, authpriv, ftp,  local0,  local1,  local2,
	      local3, local4, local5, local6, local7.  Can also	be set to none
	      to disable syslog	output completely.

       timeout
	      is used to control how long greylist tuples are retained in  the
	      database.	  Value	 is in seconds,	except if a suffix is given (m
	      for minutes, h for hours,	d for days). Default is	5 days.

       extendedregex
	      Use extended regular expressions instead of  basic  regular  ex-
	      pressions.

       unbracket
	      Attempt  to  resolve  sender  address  when the MTA handed it as
	      bracketed	IP address (e.g.: [192.0.2.18] ). Default is to	 leave
	      it as is.

       maxpeek
	      Limit  (in  bytes)  how much of messages are examined for	header
	      and body searches.

       lazyaw Make auto-whitelist look at just the IP instead of  the  (sender
	      IP, sender e-mail	address, recipient e-mail address) tuple.

       domainexact
	      match  on	 subdomain  boundaries	instead	 of the	default	suffix
	      matching.	 E.g. if domainexact is	not enabled (the default) then
	      gle.com  will  match  google.com	in addition to gle.com.	If do-
	      mainexact	is enabled then, domain	names will match on  subdomain
	      boundaries  (e.g.	  gle.com  will	match mail.gle.com and gle.com
	      but not google.com)

       drac db
	      Tell where the DRAC DB file is. This is only available  if  DRAC
	      support was compiled in. Here is an example:

		drac db	"/usr/local/etc/drac.db"

       nodrac Disable DRAC.

       logexpired
	      This option causes greylist entries that expire to be logged via
	      syslog.  This allows you to easily collect the IP	addresses  and
	      sender  names  and use them for blacklisting, SPAM scoring, etc.
	      Normally,	expiration's are only logged if	the  debug  option  is
	      set, but that generates a	lot of extra messages.

       localaddr
	      This  keyword  can be used to manually define the	local MTA's IP
	      address for such uses as spf self	and p0f	in absence of the mil-
	      ter-API {if_addr}	macro support in your MTA (Postfix, Sun/Oracle
	      CommSuite	Messaging Server).  This is not	so useful  when	 using
	      Sendmail,	since it serves	the macro and the local	address	can be
	      detected automatically.

       The configuration file is reloaded automatically	once  it  is  modified
       when  new  e-mail arrives. Most configuration keywords will take	effect
       immediately, except the following, which	will only take effect after  a
       restart of milter-greylist(8): nodetach,	pidfile, socket, and user.

       The  dumpfreq  option  can  be changed dynamically, but the change will
       only take effect	after the next dump.

       multiracl
	      By default, once a RCPT-stage ACL	whitelists a  recipient,  next
	      recipient	gets automatically whitelisted.	This historical	behav-
	      ior can be considered a bug, and this option disables it.

FORMAT STRINGS
       Various statements in the configuration	file  accept  format  strings,
       where the following % prefixed tokens are substituted. Here is the com-
       plete list of available substitutions (Note that	some substitutions are
       not relevant in any context).

       %r     the  message  recipient  e-mail address. This is not substituted
	      for DATA stage ACL since there can be  multiple  recipients  for
	      the message.

       %f     the message sender e-mail	address

       %i     the sender machine IP address

       %j     the reversed sender machine IP address. For instance, 192.0.2.12
	      becomes 12.2.0.192.

       %I     the sender machine IP address masked by a	CIDR. Example: %I{/24}

       %d     the sender machine DNS address

       %h     the SMTP transaction HELO	string

       %mr    the mailbox part of %r (before the @ sign). This is not  substi-
	      tuted  for DATA stage ACL	since there can	be multiple recipients
	      for the message.

       %sr    the site part of %r (after the @ sign). This is not  substituted
	      for  DATA	 stage	ACL since there	can be multiple	recipients for
	      the message.

       %mf    the mailbox part of %f (before the @ sign)

       %sf    the site part of %f (after the @ sign)

       %md    the machine part of %d (before the first . sign)

       %sd    the site part of %d (after the first . sign)

       %Xc    the SMTP code returned

       %Xe    the SMTP extended	code returned

       %Xm    the SMTP message returned

       %Xh    the message displayed in the X-Greylist header

       %D     Comma-separated list of DNSRBL for which the sender host matched

       %M     a	sendmail macro value. Examples:	%Mj or %M{if_addr}

       %g     a	regex back reference. For instance, %g{\2} is  substituted  by
	      the  string  matching  the  second  parenthesis group in all ACL
	      regex clauses

       %T     a	brace-enclosed strftime(3) format string that will be  substi-
	      tuted by the system time.	Example: %T{%Y%m%d:%H%M%S}

       %v     milter-greylist's	version

       %G     Offset to	GMT (e.g.: -0100)

       %C     Sender  IP  country  code,  as  reported	by GeoIP. This is only
	      available	if milter-greylist was built with GeoIP	support

       %Fx    p0f OS fingerprint genre and detail. This	is only	 available  if
	      milter-greylist was built	with p0f support.

       %V     Shortcut	to  "milter-greylist-%v	(%Mj [%M{if_addr}]); %T{%a, %d
	      %b %Y %T}	%G (%T{%Z})"

       %S     the action performed: accept, tempfail, or reject.

       %A     the line number of the ACL that caused the action.

       %a     the id string of the ACL that caused the action. If  no  id  was
	      given, the line number is	used instead.

       %cA    the  line	 number	of the ACL being evaluated, whether it matches
	      or not.

       %ca    the id string of the ACL being avaluated,	whether	it matches  or
	      not.  If no id was given,	the line number	is used	instead.

       %Et    total  elapsed  time  in seconds before a	greylisted message has
	      been accepted

       %Eh    hours elapsed

       %Em    minutes elapsed (modulo one hour)

       %Es    seconds elapsed (modulo one minute)

       %E     shortcut to %Eh:%Em:Es

       %Rt    total remaining time in seconds before a greylisted message will
	      be accepted

       %Rh    hours remaining

       %Rm    minutes remaining	(modulo	one hour)

       %Rs    seconds remaining	(modulo	one minute)

       %R     shortcut to %Rh:%Rm:Rs

       %Hs    SpamAssassin score (if build with	SpamAssassin support)

       %pn    Name of last LDAP	or CURL	gathered property that matched an ACL.

       %pv    Value  of	 last  LDAP  or	CURL gathered property that matched an
	      ACL.

       %pr    Recipient	that caused storage of the last	matching LDAP or  CURL
	      gathered property.  %P a LDAP or CURL gathered propery. Example:
	      %P{mail} Note that this copes very badly with multivalued	 prop-
	      erties.

       %Qd    DKIM  query  result  (pass, fail,	etc.), if built	with DKIM sup-
	      port.

       %Qs    SPF query	result (pass, (soft)fail, etc.),  if  built  with  SPF
	      support.

       %QA    Authentication  results summary, suitable	for Authentication-Re-
	      sults header. Will included formatted query  results  from  DKIM
	      and SPF if checked.

       %QS    SPF  result,  suitable  for  Received-SPF	header.	Available when
	      compiled with libspf2.

       %%     a	single % character

AUTHORS
       Emmanuel	Dreyfus	<manu@netbsd.org>

       milter-greylist received	many contributions from	(in  alphabetical  or-
       der):  Adrian Dabrowski,	Aida Shinra, Adam Katz,	Alexander Lobodzinski,
       Alexandre Cherif, Alexey	Popov, Andrew McGill, Attila Bruncsak,	Benoit
       Branciard, Bernhard Schneider, Bob Smith, Constantine A.	Murenin, Chris
       Bennett,	Christian Pelissier, Cyril Guibourg, Dan Hollis, David Binder-
       man,  Denis  Solovyov,  Elrond,	Enrico	Scholz,	Eugene Crosser,	Fabien
       Tassin, Fredrik Pettai, Gary Aitken, Georg  Horn,  Gert	Doering,  Greg
       Troxel,	Guido Kerkewitz, Hajimu	Umemoto, Hideki	ONO, Ivan F. Martinez,
       Jacques Beigbeder, Jean	Benoit,	 Jean-Jacques  Puig,  Jeff  Rife,  Jim
       Klimov,	Jobst  Schmalenbach,  Joe  Pruett,  Joel  Bertrand,  Johann E.
       Klasek, Johann  Klasek,	John  Thiltges,	 John  Wood,  Jorgen  Lundman,
       Kazuyuki	 Yoshida, Klas Heggemann, Kouhei Sutou,	Laurence Moindrot, Lev
       Walkin, Manuel Badzong, Mart Pirita, Martin Paul, Matt Kettler, Mattheu
       Herrb,  Matthias	 Scheler, Matthieu Herrb, Michael Fromme, Moritz Both,
       Nerijus Baliunas, Ole Hansen, Pavel Cahyna, Pascal Lalonde,  Per	 Holm,
       Petar  Bogdanovic,  Petr	Kristof, Piotr Wadas, R	P Herrold, Ralf	S. En-
       gelschall, Ranko	Zivojnovic, Remy Card, Rick Adams, Rogier Maas,	Romain
       Kang, Rudy Eschauzier, Stephane Lentz, Steven Hiscocks, Thomas Scheune-
       mann, Tim Mooney, Vincent Dufresne,  Wolfgang  Solfrank,	 and  Yaroslav
       Boychuk.

       Thanks  to  Helmut  Messerer  and Thomas	Pfau for their feedback	on the
       first releases of this software.

SEE ALSO
       milter-greylist(8), sendmail(8),	syslogd(8).

       Evan Harris's paper:
	      http://projects.puremagic.com/greylisting/

       milter-greylist's web site:
	      http://hcpnet.free.fr/milter-greylist/

				 May 10, 2005		      greylist.conf(5)

NAME | DESCRIPTION | WHITELIST | DATA-STAGE ACL | LISTS | BACKWARD COMPATIBILITY | MX SYNC | TEXT DUMP | REPORTING | SENDER CALLBACK SYSTEMS | SENDMAIL MACROS | DNSRBL | DNS updates | PROPERTIES | URL checks | LDAP CHECKS | RATE LIMIT | CUSTOM REPORTS | COMMAND-LINE FLAG EQUIVALENTS | MISCELLANEOUS | FORMAT STRINGS | AUTHORS | SEE ALSO

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