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#++
# NAME
#	ldap_table 5
# SUMMARY
#	Postfix LDAP client configuration
# SYNOPSIS
#	\fBpostmap -q "\fIstring\fB" ldap:/etc/postfix/\fIfilename\fR
#
#	\fBpostmap -q - ldap:/etc/postfix/\fIfilename\fB <\fIinputfile\fR
# DESCRIPTION
#	The Postfix mail system uses optional tables for address
#	rewriting or mail routing. These tables are usually in
#	\fBdbm\fR or \fBdb\fR format.
#
#	Alternatively, lookup tables can be specified as LDAP databases.
#
#	In order to use LDAP lookups, define an LDAP source as a lookup
#	table in main.cf, for example:
#
# .nf
#	    alias_maps = ldap:/etc/postfix/ldap-aliases.cf
# .fi
#
#	The file /etc/postfix/ldap-aliases.cf has the same format as
#	the Postfix main.cf file, and can specify the parameters
#	described below. An example is given at the end of this manual.
#
#	This configuration method is available with Postfix version
#	2.1 and later.  See the section "OBSOLETE MAIN.CF PARAMETERS"
#	below for older Postfix versions.
#
#	For details about LDAP SSL and STARTTLS, see the section
#	on SSL and STARTTLS below.
# LIST MEMBERSHIP
# .ad
# .fi
#	When using LDAP to store lists such as $mynetworks,
#	$mydestination, $relay_domains, $local_recipient_maps,
#	etc., it is important to understand that the table must
#	store each list member as a separate key. The table lookup
#	verifies the *existence* of the key. See "Postfix lists
#	versus tables" in the DATABASE_README document for a
#	discussion.
#
#	Do NOT create tables that return the full list of domains
#	in $mydestination or $relay_domains etc., or IP addresses
#	in $mynetworks.
#
#	DO create tables with each matching item as a key and with
#	an arbitrary value. With LDAP databases it is not uncommon to
#	return the key itself.
#
#	For example, NEVER do this in a map defining $mydestination:
#
# .nf
#	    query_filter = domain=* 
#	    result_attribute = domain
# .fi
#
#	Do this instead:
#
# .nf
#	    query_filter = domain=%s 
#	    result_attribute = domain
# .fi
# GENERAL LDAP PARAMETERS
# .ad
# .fi
#	In the text below, default values are given in parentheses.
#	Note: don't use quotes in these variables; at least, not until the
#	Postfix configuration routines understand how to deal with quoted
#	strings.
# .IP "\fBserver_host (default: localhost)\fR"
#	The name of the host running the LDAP server, e.g.
#
# .nf
#	    server_host = ldap.example.com
# .fi
#
#	Depending on the LDAP client library you're using, it should
#	be possible to specify multiple servers here, with the library
#	trying them in order should the first one fail. It should also
#	be possible to give each server in the list a different port
#	(overriding \fBserver_port\fR below), by naming them like
#
# .nf
#	    server_host = ldap.example.com:1444
# .fi
#
#	With OpenLDAP, a (list of) LDAP URLs can be used to specify both
#	the hostname(s) and the port(s):
#
# .nf
#	    server_host = ldap://ldap.example.com:1444
#	                ldap://ldap2.example.com:1444
# .fi
#
#	All LDAP URLs accepted by the OpenLDAP library are supported,
#	including connections over UNIX domain sockets, and LDAP SSL
#	(the last one provided that OpenLDAP was compiled with support
#	for SSL):
#
# .nf
#	    server_host = ldapi://%2Fsome%2Fpath
#	                ldaps://ldap.example.com:636
# .fi
# .IP "\fBserver_port (default: 389)\fR"
#	The port the LDAP server listens on, e.g.
#
# .nf
#	    server_port = 778
# .fi
# .IP "\fBtimeout (default: 10 seconds)\fR"
#	The number of seconds a search can take before timing out, e.g.
#
# .fi
#	    timeout = 5
# .fi
# .IP "\fBsearch_base (No default; you must configure this)\fR"
#	The RFC2253 base DN at which to conduct the search, e.g.
#
# .nf
#	    search_base = dc=your, dc=com
# .fi
# .IP
#	With Postfix 2.2 and later this parameter supports the
#	following '%' expansions:
# .RS
# .IP "\fB%%\fR"
#	This is replaced by a literal '%' character.
# .IP "\fB%s\fR"
#	This is replaced by the input key.
#	RFC 2253 quoting is used to make sure that the input key
#	does not add unexpected metacharacters.
# .IP "\fB%u\fR"
#	When the input key is an address of the form user@domain, \fB%u\fR
#	is replaced by the (RFC 2253) quoted local part of the address.
#	Otherwise, \fB%u\fR is replaced by the entire search string.
#	If the localpart is empty, the search is suppressed and returns
#	no results.
# .IP "\fB%d\fR"
#	When the input key is an address of the form user@domain, \fB%d\fR
#	is replaced by the (RFC 2253) quoted domain part of the address.
#	Otherwise, the search is suppressed and returns no results.
# .IP "\fB%[SUD]\fR"
#	For the \fBsearch_base\fR parameter, the upper-case equivalents
#	of the above expansions behave identically to their lower-case
#	counter-parts. With the \fBresult_format\fR parameter (previously
#	called \fBresult_filter\fR see the COMPATIBILITY section and below),
#	they expand to the corresponding components of input key rather
#	than the result value.
# .IP "\fB%[1-9]\fR"
#	The patterns %1, %2, ... %9 are replaced by the corresponding
#	most significant component of the input key's domain. If the
#	input key is \fIuser@mail.example.com\fR, then %1 is \fBcom\fR,
#	%2 is \fBexample\fR and %3 is \fBmail\fR. If the input key is
#	unqualified or does not have enough domain components to satisfy
#	all the specified patterns, the search is suppressed and returns
#	no results.
# .RE
# .IP "\fBquery_filter (default: mailacceptinggeneralid=%s)\fR"
#	The RFC2254 filter used to search the directory, where \fB%s\fR
#	is a substitute for the address Postfix is trying to resolve,
#	e.g.
#
# .nf
#	    query_filter = (&(mail=%s)(paid_up=true))
# .fi
#
#	This parameter supports the following '%' expansions:
# .RS
# .IP "\fB%%\fR"
#	This is replaced by a literal '%' character. (Postfix 2.2 and later).
# .IP "\fB%s\fR"
#	This is replaced by the input key.
#	RFC 2254 quoting is used to make sure that the input key
#	does not add unexpected metacharacters.
# .IP "\fB%u\fR"
#	When the input key is an address of the form user@domain, \fB%u\fR
#	is replaced by the (RFC 2254) quoted local part of the address.
#	Otherwise, \fB%u\fR is replaced by the entire search string.
#	If the localpart is empty, the search is suppressed and returns
#	no results.
# .IP "\fB%d\fR"
#	When the input key is an address of the form user@domain, \fB%d\fR
#	is replaced by the (RFC 2254) quoted domain part of the address.
#	Otherwise, the search is suppressed and returns no results.
# .IP "\fB%[SUD]\fR"
#	The upper-case equivalents of the above expansions behave in the
#	\fBquery_filter\fR parameter identically to their lower-case
#	counter-parts. With the \fBresult_format\fR parameter (previously
#	called \fBresult_filter\fR see the COMPATIBILITY section and below),
#	they expand to the corresponding components of input key rather
#	than the result value.
# .IP
#	The above %S, %U and %D expansions are available with Postfix 2.2
#	and later.
# .IP "\fB%[1-9]\fR"
#	The patterns %1, %2, ... %9 are replaced by the corresponding
#	most significant component of the input key's domain. If the
#	input key is \fIuser@mail.example.com\fR, then %1 is \fBcom\fR,
#	%2 is \fBexample\fR and %3 is \fBmail\fR. If the input key is
#	unqualified or does not have enough domain components to satisfy
#	all the specified patterns, the search is suppressed and returns
#	no results.
# .IP
#	The above %1, ..., %9 expansions are available with Postfix 2.2
#	and later.
# .RE
# .IP
#	The "domain" parameter described below limits the input
#	keys to addresses in matching domains. When the "domain"
#	parameter is non-empty, LDAP queries for unqualified
#	addresses or addresses in non-matching domains are suppressed
#	and return no results.
#
#	NOTE: DO NOT put quotes around the \fBquery_filter\fR parameter.
# .IP "\fBresult_format (default: \fB%s\fR)\fR"
#	Called \fBresult_filter\fR in Postfix releases prior to 2.2.
#	Format template applied to result attributes. Most commonly used
#	to append (or prepend) text to the result. This parameter supports
#	the following '%' expansions:
# .RS
# .IP "\fB%%\fR"
#	This is replaced by a literal '%' character. (Postfix 2.2 and later).
# .IP "\fB%s\fR"
#	This is replaced by the value of the result attribute. When
#	result is empty it is skipped.
# .IP "\fB%u\fR
#	When the result attribute value is an address of the form
#	user@domain, \fB%u\fR is replaced by the local part of the
#	address. When the result has an empty localpart it is skipped.
# .IP "\fB%d\fR"
#	When a result attribute value is an address of the form
#	user@domain, \fB%d\fR is replaced by the domain part of
#	the attribute value. When the result is unqualified it
#	is skipped.
# .IP "\fB%[SUD1-9]\fR"
#	The upper-case and decimal digit expansions interpolate
#	the parts of the input key rather than the result. Their
#	behavior is identical to that described with \fBquery_filter\fR,
#	and in fact because the input key is known in advance, lookups
#	whose key does not contain all the information specified in
#	the result template are suppressed and return no results.
# .IP
#	The above %S, %U, %D and %1, ..., %9 expansions are available with
#	Postfix 2.2 and later.
# .RE
# .IP
#	For example, using "result_format = smtp:[%s]" allows one
#	to use a mailHost attribute as the basis of a transport(5)
#	table. After applying the result format, multiple values
#	are concatenated as comma separated strings. The expansion_limit
#	and size_limit parameters explained below allow one to
#	restrict the number of values in the result, which is
#	especially useful for maps that should return a single
#	value.
#
#	The default value \fB%s\fR specifies that each
#	attribute value should be used as is.
#
#	This parameter was called \fBresult_filter\fR in Postfix
#	releases prior to 2.2. If no "result_format" is specified,
#	the value of "result_filter" will be used instead before
#	resorting to the default value. This provides compatibility
#	with old configuration files.
#
#	NOTE: DO NOT put quotes around the result format!
# .IP "\fBdomain (default: no domain list)\fR"
#	This is a list of domain names, paths to files, or
#	dictionaries. When specified, only fully qualified search
#	keys with a *non-empty* localpart and a matching domain
#	are eligible for lookup: 'user' lookups, bare domain lookups
#	and "@domain" lookups are not performed. This can significantly
#	reduce the query load on the LDAP server.
#
# .nf
#	    domain = postfix.org, hash:/etc/postfix/searchdomains
# .fi
#
#	It is best not to use LDAP to store the domains eligible
#	for LDAP lookups.
#
#	NOTE: DO NOT define this parameter for local(8) aliases.
#
#	This feature is available in Postfix 1.0 and later.
# .IP "\fBresult_attribute (default: maildrop)\fR"
#	The attribute(s) Postfix will read from any directory
#	entries returned by the lookup, to be resolved to an email
#	address.
#
# .nf
#	    result_attribute = mailbox, maildrop
# .fi
#
#	Don't rely on the default value ("maildrop"). Set the
#	result_attribute explicitly in all ldap table configuration
#	files. This is particularly relevant when no result_attribute
#	is applicable, e.g. cases in which leaf_result_attribute and/or
#	terminal_result_attribute are used instead. The default value
#	is harmless if "maildrop" is also listed as a leaf or terminal
#	result attribute, but it is best to not leave this to chance.
# .IP "\fBspecial_result_attribute (default: empty)\fR"
#	The attribute(s) of directory entries that can contain DNs
#	or RFC 2255 LDAP URLs. If found, a recursive search
#	is performed to retrieve the entry referenced by the DN, or
#	the entries matched by the URL query.
#
# .nf
#	    special_result_attribute = memberdn
# .fi
#
#	DN recursion retrieves the same result_attributes as the
#	main query, including the special attributes for further
#	recursion.
#
#	URL processing retrieves only those attributes that are included
#	in both the URL definition and as result attributes (ordinary,
#	special, leaf or terminal) in the Postfix table definition.
#	If the URL lists any of the table's special result attributes,
#	these are retrieved and used recursively. A URL that does not
#	specify any attribute selection, is equivalent (RFC 2255) to a
#	URL that selects all attributes, in which case the selected
#	attributes will be the full set of result attributes in the
#	Postfix table.
#
#	If an LDAP URL attribute-descriptor or the corresponding Postfix
#	LDAP table result attribute (but not both) uses RFC 2255 sub-type
#	options ("attr;option"), the attribute requested from the LDAP server
#	will include the sub-type option. In all other cases, the URL
#	attribute and the table attribute must match exactly. Attributes
#	with options in both the URL and the Postfix table are requested
#	only when the options are identical. LDAP attribute-descriptor
#	options are very rarely used, most LDAP users will not
#	need to concern themselves with this level of nuanced detail.
# .IP "\fBterminal_result_attribute (default: empty)\fR"
#	When one or more terminal result attributes are found in an LDAP
#	entry, all other result attributes are ignored and only the terminal
#	result attributes are returned. This is useful for delegating expansion
#	of group members to a particular host, by using an optional "maildrop"
#	attribute on selected groups to route the group to a specific host,
#	where the group is expanded, possibly via mailing-list manager or
#	other special processing.
#
# .nf
#	    result_attribute =
#	    terminal_result_attribute = maildrop
# .fi
#
#	When using terminal and/or leaf result attributes, the
#	result_attribute is best set to an empty value when it is not
#	used, or else explicitly set to the desired value, even if it is
#	the default value "maildrop".
#
#	This feature is available with Postfix 2.4 or later.
# .IP "\fBleaf_result_attribute (default: empty)\fR"
#	When one or more special result attributes are found in a non-terminal
#	(see above) LDAP entry, leaf result attributes are excluded from the
#	expansion of that entry. This is useful when expanding groups and the
#	desired mail address attribute(s) of the member objects obtained via
#	DN or URI recursion are also present in the group object. To only
#	return the attribute values from the leaf objects and not the
#	containing group, add the attribute to the leaf_result_attribute list,
#	and not the result_attribute list, which is always expanded. Note,
#	the default value of "result_attribute" is not empty, you may want to
#	set it explicitly empty when using "leaf_result_attribute" to expand
#	the group to a list of member DN addresses. If groups have both
#	member DN references AND attributes that hold multiple string valued
#	rfc822 addresses, then the string attributes go in "result_attribute".
#	The attributes that represent the email addresses of objects
#	referenced via a DN (or LDAP URI) go in "leaf_result_attribute".
#
# .nf
#	    result_attribute = memberaddr
#	    special_result_attribute = memberdn
#	    terminal_result_attribute = maildrop
#	    leaf_result_attribute = mail
# .fi
#
#	When using terminal and/or leaf result attributes, the
#	result_attribute is best set to an empty value when it is not
#	used, or else explicitly set to the desired value, even if it is
#	the default value "maildrop".
#
#	This feature is available with Postfix 2.4 or later.
# .IP "\fBscope (default: sub)\fR"
#	The LDAP search scope: \fBsub\fR, \fBbase\fR, or \fBone\fR.
#	These translate into LDAP_SCOPE_SUBTREE, LDAP_SCOPE_BASE,
#	and LDAP_SCOPE_ONELEVEL.
# .IP "\fBbind (default: yes)\fR"
#	Whether or how to bind to the LDAP server. Newer LDAP
#	implementations don't require clients to bind, which saves
#	time. Example:
#
# .nf
#	    # Don't bind
#	    bind = no
#	    # Use SIMPLE bind
#	    bind = yes
#	    # Use SASL bind
#	    bind = sasl
# .fi
#
#	Postfix versions prior to 2.8 only support "bind = no" which
#	means don't bind, and "bind = yes" which means do a SIMPLE bind.
#	Postfix 2.8 and later also supports "bind = SASL" when compiled
#	with LDAP SASL support as described in LDAP_README, it also adds
#	the synonyms "bind = none" and "bind = simple" for "bind = no"
#	and "bind = yes" respectively. See the SASL section below for
#	additional parameters available with "bind = sasl".
#
#	If you do need to bind, you might consider configuring
#	Postfix to connect to the local machine on a port that's
#	an SSL tunnel to your LDAP server. If your LDAP server
#	doesn't natively support SSL, put a tunnel (wrapper, proxy,
#	whatever you want to call it) on that system too. This
#	should prevent the password from traversing the network in
#	the clear.
# .IP "\fBbind_dn (default: empty)\fR"
#	If you do have to bind, do it with this distinguished name. Example:
#
# .nf
#	    bind_dn = uid=postfix, dc=your, dc=com
# .fi
#	With "bind = sasl" (see above) the DN may be optional for some SASL
#	mechanisms, don't specify a DN if not needed.
# .IP "\fBbind_pw (default: empty)\fR"
#	The password for the distinguished name above. If you have
#	to use this, you probably want to make the map configuration
#	file readable only by the Postfix user. When using the
#	obsolete ldap:ldapsource syntax, with map parameters in
#	main.cf, it is not possible to securely store the bind
#	password. This is because main.cf needs to be world readable
#	to allow local accounts to submit mail via the sendmail
#	command. Example:
#
# .nf
#	    bind_pw = postfixpw
# .fi
#	With "bind = sasl" (see above) the password may be optional
#	for some SASL mechanisms, don't specify a password if not needed.
# .IP "\fBcache (IGNORED with a warning)\fR"
# .IP "\fBcache_expiry (IGNORED with a warning)\fR"
# .IP "\fBcache_size (IGNORED with a warning)\fR"
#	The above parameters are NO LONGER SUPPORTED by Postfix.
#	Cache support has been dropped from OpenLDAP as of release
#	2.1.13.
# .IP "\fBrecursion_limit (default: 1000)\fR"
#	A limit on the nesting depth of DN and URL special result
#	attribute evaluation. The limit must be a non-zero positive
#	number.
# .IP "\fBexpansion_limit (default: 0)\fR"
#	A limit on the total number of result elements returned
#	(as a comma separated list) by a lookup against the map.
#	A setting of zero disables the limit. Lookups fail with a
#	temporary error if the limit is exceeded.  Setting the
#	limit to 1 ensures that lookups do not return multiple
#	values.
# .IP "\fBsize_limit (default: $expansion_limit)\fR"
#	A limit on the number of LDAP entries returned by any single
#	LDAP search performed as part of the lookup. A setting of
#	0 disables the limit.  Expansion of DN and URL references
#	involves nested LDAP queries, each of which is separately
#	subjected to this limit.
#
#	Note: even a single LDAP entry can generate multiple lookup
#	results, via multiple result attributes and/or multi-valued
#	result attributes. This limit caps the per search resource
#	utilization on the LDAP server, not the final multiplicity
#	of the lookup result. It is analogous to the "-z" option
#	of "ldapsearch".
# .IP "\fBdereference (default: 0)\fR"
#	When to dereference LDAP aliases. (Note that this has
#	nothing do with Postfix aliases.) The permitted values are
#	those legal for the OpenLDAP/UM LDAP implementations:
# .RS
# .IP 0 
#	never
# .IP 1 
#	when searching
# .IP 2 
#	when locating the base object for the search
# .IP 3 
#	always
# .RE
# .IP
#	See ldap.h or the ldap_open(3) or ldapsearch(1) man pages
#	for more information. And if you're using an LDAP package
#	that has other possible values, please bring it to the
#	attention of the postfix-users@postfix.org mailing list.
# .IP "\fBchase_referrals (default: 0)\fR"
#	Sets (or clears) LDAP_OPT_REFERRALS (requires LDAP version
#	3 support).
# .IP "\fBversion (default: 2)\fR"
#	Specifies the LDAP protocol version to use.
# .IP "\fBdebuglevel (default: 0)\fR"
#	What level to set for debugging in the OpenLDAP libraries.
# LDAP SASL PARAMETERS
# .ad
# .fi
#	If you're using the OpenLDAP libraries compiled with SASL
#	support, Postfix 2.8 and later built with LDAP SASL support
#	as described in LDAP_README can authenticate to LDAP servers
#	via SASL.
#
#	This enables authentication to the LDAP server via mechanisms
#	other than a simple password. The added flexibility has a cost:
#	it is no longer practical to set an explicit timeout on the duration
#	of an LDAP bind operation. Under adverse conditions, whether a SASL
#	bind times out, or if it does, the duration of the timeout is
#	determined by the LDAP and SASL libraries.
#
# 	It is best to use tables that use SASL binds via proxymap(8), this
#	way the requesting process can time-out the proxymap request. This
#	also lets you tailer the process environment by overriding the
#	proxymap(8) import_environment setting in master.cf(5). Special
#	environment settings may be needed to configure GSSAPI credential
#	caches or other SASL mechanism specific options. The GSSAPI
#	credentials used for LDAP lookups may need to be different than
#	say those used for the Postfix SMTP client to authenticate to remote
#	servers.
#
#	Using SASL mechanisms requires LDAP protocol version 3, the default
#	protocol version is 2 for backwards compatibility. You must set
#	"version = 3" in addition to "bind = sasl".
#
#	The following parameters are relevant to using LDAP with SASL
# .IP "\fBsasl_mechs (default: empty)\fR"
#	Space separated list of SASL mechanism(s) to try. 
# .IP "\fBsasl_realm (default: empty)\fR"
#	SASL Realm to use, if applicable.
# .IP "\fBsasl_authz_id (default: empty)\fR"
#	The SASL authorization identity to assert, if applicable.
# .IP "\fBsasl_minssf (default: 0)\fR"
#	The minimum required sasl security factor required to establish a
#	connection.
# LDAP SSL AND STARTTLS PARAMETERS
# .ad
# .fi
#	If you're using the OpenLDAP libraries compiled with SSL
#	support, Postfix can connect to LDAP SSL servers and can
#	issue the STARTTLS command. 
#
#	LDAP SSL service can be requested by using a LDAP SSL URL
#	in the server_host parameter:
#
# .nf
#	    server_host = ldaps://ldap.example.com:636
# .fi
#
#	STARTTLS can be turned on with the start_tls parameter:
#
# .nf
#	    start_tls = yes
# .fi
#
#	Both forms require LDAP protocol version 3, which has to be set
#	explicitly with:
#
# .nf
#	    version = 3
# .fi
#
#	If any of the Postfix programs querying the map is configured in
#	master.cf to run chrooted, all the certificates and keys involved
#	have to be copied to the chroot jail. Of course, the private keys
#	should only be readable by the user "postfix".
#
#	The following parameters are relevant to LDAP SSL and STARTTLS:
# .IP "\fBstart_tls (default: no)\fR"
#	Whether or not to issue STARTTLS upon connection to the
#	server.  Don't set this with LDAP SSL (the SSL session is setup
#	automatically when the TCP connection is opened).
# .IP "\fBtls_ca_cert_dir (No default; set either this or tls_ca_cert_file)\fR"
#	Directory containing X509 Certification Authority certificates
#	in PEM format which are to be recognized by the client in
#	SSL/TLS connections. The files each contain one CA certificate.
#	The files are looked up by the CA subject name hash value,
#	which must hence be available. If more than one CA certificate
#	with the same name hash value exist, the extension must be
#	different (e.g. 9d66eef0.0, 9d66eef0.1 etc). The search is
#	performed in the ordering of the extension number, regardless
#	of other properties of the certificates. Use the c_rehash
#	utility (from the OpenSSL distribution) to create the
#	necessary links.
# .IP "\fBtls_ca_cert_file (No default; set either this or tls_ca_cert_dir)\fR"
#	File containing the X509 Certification Authority certificates
#	in PEM format which are to be recognized by the client in
#	SSL/TLS connections. This setting takes precedence over
#	tls_ca_cert_dir.
# .IP "\fBtls_cert (No default; you must set this)\fR"
#	File containing client's X509 certificate to be used by
#	the client in SSL/ TLS connections.
# .IP "\fBtls_key (No default; you must set this)\fR"
#	File containing the private key corresponding to the above
#	tls_cert.
# .IP "\fBtls_require_cert (default: no)\fR"
#	Whether or not to request server's X509 certificate and
#	check its validity when establishing SSL/TLS connections.
#	The supported values are \fBno\fR and \fByes\fR.
# .sp
#	With \fBno\fR, the server certificate trust chain is not checked,
#	but with OpenLDAP prior to 2.1.13, the name in the server
#	certificate must still match the LDAP server name. With OpenLDAP
#	2.0.0 to 2.0.11 the server name is not necessarily what you
#	specified, rather it is determined (by reverse lookup) from the
#	IP address of the LDAP server connection. With OpenLDAP prior to
#	2.0.13, subjectAlternativeName extensions in the LDAP server
#	certificate are ignored: the server name must match the subject
#	CommonName. The \fBno\fR setting corresponds to the \fBnever\fR
#	value of \fBTLS_REQCERT\fR in LDAP client configuration files.
# .sp
#	Don't use TLS with OpenLDAP 2.0.x (and especially with x <= 11)
#	if you can avoid it.
# .sp
#	With \fByes\fR, the server certificate must be issued by a trusted
#	CA, and not be expired. The LDAP server name must match one of the
#	name(s) found in the certificate (see above for OpenLDAP library
#	version dependent behavior). The \fByes\fR setting corresponds to the
#	\fBdemand\fR value of \fBTLS_REQCERT\fR in LDAP client configuration
#	files.
# .sp
#	The "try" and "allow" values of \fBTLS_REQCERT\fR have no equivalents
#	here. They are not available with OpenLDAP 2.0, and in any case have
#	questionable security properties. Either you want TLS verified LDAP
#	connections, or you don't.
# .sp
#	The \fByes\fR value only works correctly with Postfix 2.5 and later,
#	or with OpenLDAP 2.0. Earlier Postfix releases or later OpenLDAP
#	releases don't work together with this setting. Support for LDAP
#	over TLS was added to Postfix based on the OpenLDAP 2.0 API.
# .IP "\fBtls_random_file (No default)\fR"
#	Path of a file to obtain random bits from when /dev/[u]random
#	is not available, to be used by the client in SSL/TLS
#	connections.
# .IP "\fBtls_cipher_suite (No default)\fR"
#	Cipher suite to use in SSL/TLS negotiations.
# EXAMPLE
# .ad
# .fi
#	Here's a basic example for using LDAP to look up local(8)
#	aliases.
#	Assume that in main.cf, you have:
#
# .nf
#	    alias_maps = hash:/etc/aliases,
#	            ldap:/etc/postfix/ldap-aliases.cf
# .fi
#
#	and in ldap:/etc/postfix/ldap-aliases.cf you have:
#
# .nf
#	    server_host = ldap.example.com
#	    search_base = dc=example, dc=com
# .fi
#
#	Upon receiving mail for a local address "ldapuser" that
#	isn't found in the /etc/aliases database, Postfix will
#	search the LDAP server listening at port 389 on ldap.example.com.
#	It will bind anonymously, search for any directory entries
#	whose mailacceptinggeneralid attribute is "ldapuser", read
#	the "maildrop" attributes of those found, and build a list
#	of their maildrops, which will be treated as RFC822 addresses
#	to which the message will be delivered.
# OBSOLETE MAIN.CF PARAMETERS
# .ad
# .fi
#	For backwards compatibility with Postfix version 2.0 and earlier,
#	LDAP parameters can also be defined in main.cf.  Specify
#	as LDAP source a name that doesn't begin with a slash or
#	a dot.  The LDAP parameters will then be accessible as the
#	name you've given the source in its definition, an underscore,
#	and the name of the parameter.  For example, if the map is
#	specified as "ldap:\fIldapsource\fR", the "server_host"
#	parameter below would be defined in main.cf as
#	"\fIldapsource\fR_server_host".
#
#	Note: with this form, the passwords for the LDAP sources are
#	written in main.cf, which is normally world-readable.  Support
#	for this form will be removed in a future Postfix version.
# OTHER OBSOLETE FEATURES
# .ad
# .fi
#	For backwards compatibility with the pre
#	2.2 LDAP clients, \fBresult_filter\fR can for now be used instead
#	of \fBresult_format\fR, when the latter parameter is not also set.
#	The new name better reflects the function of the parameter. This
#	compatibility interface may be removed in a future release.
# SEE ALSO
#	postmap(1), Postfix lookup table manager
#	postconf(5), configuration parameters
#	mysql_table(5), MySQL lookup tables
#	pgsql_table(5), PostgreSQL lookup tables
# README FILES
# .ad
# .fi
#	Use "\fBpostconf readme_directory\fR" or
#	"\fBpostconf html_directory\fR" to locate this information.
# .na
# .nf
#	DATABASE_README, Postfix lookup table overview
#	LDAP_README, Postfix LDAP client guide
# LICENSE
# .ad
# .fi
#	The Secure Mailer license must be distributed with this software.
# AUTHOR(S)
# .ad
# .fi
#	Carsten Hoeger,
#	Hery Rakotoarisoa,
#	John Hensley, 
#	Keith Stevenson,
#	LaMont Jones,
#	Liviu Daia,
#	Manuel Guesdon, 
#	Mike Mattice,
#	Prabhat K Singh,
#	Sami Haahtinen,
#	Samuel Tardieu,
#	Victor Duchovni,
#	and many others.
#--