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SLAPD.ACCESS(5)
NAME
  slapd.access - access configuration for slapd, the stand-alone LDAP daemon

SYNOPSIS
  /usr/internet/openldap/etc/slapd.conf

DESCRIPTION
  The slapd.conf(5) file contains configuration information for the slapd(8)
  daemon. This configuration file is also used by the slurpd(8) replication
  daemon and by the SLAPD tools slapadd(8), slapcat(8), and slapindex(8).

  The slapd.conf file consists of a series of global configuration options
  that apply to slapd as a whole (including all backends), followed by zero
  or more database backend definitions that contain information specific to a
  backend instance.

  The general format of slapd.conf is as follows:

      # comment - these options apply to every database
      <global configuration options>
      # first database definition & configuration options
      database	  <backend 1 type>
      <configuration options specific to backend 1>
      # subsequent database definitions & configuration options
      ...

  Both the global configuration and each backend-specific section can contain
  access information.  Backend-specific access control directives are used
  for those entries that belong to the backend, according to their naming
  context.  In case no access control directives are defined for a backend or
  those which are defined are not applicable, the directives from the global
  configuration section are then used.

  For entries not held in any backend (such as a root DSE), the directives of
  the first backend (and any global directives) are used.

  Arguments that should be replaced by actual text are shown in brackets <>.
  The structure of the access control directives is

  access to <what> [ by <who> <access> [ <control> ] ]+
       Grant access (specified by <access>) to a set of entries and/or
       attributes (specified by <what>) by one or more requestors (specified
       by <who>).

  The field <what> specifies the entity the access control directive applies
  to.  It can have the forms

	  *
	  [dn[.<dnstyle>]=<pattern>]
	  [filter=<ldapfilter>]
	  [attrs=<attrlist>]

  The wildcard * stands for all the entries.

  The statement dn=<pattern> selects the entries based on their naming
  context.  The optional style qualifier <dnstyle> can be regex (the default)
  implies that pattern is a regular expression, as detailed in regex(7),
  matching a normalized string representation of the entry's DN.  The regex
  form of the pattern does not support UTF-8 yet.

  For all other qualifiers, the pattern is a string representation of the
  entry's DN.  base or exact (an alias of base) indicates the entry whose DN
  is equal to the pattern.  one to indicate all the entries immediately below
  the pattern, subtree to indicate all entries in the subtree at the pattern,
  children to indicate all entries below (subordinate) to the pattern.	Note
  that dn=".*" is equivalent to *.

  The statement filter=<ldapfilter> selects the entries based on a valid LDAP
  filter as described in RFC 2254.

  The statement attrs=<attrlist> selects the attributes the access control
  rule applies to.  It is a comma-separated list of attribute types, plus the
  special names entry, indicating access to the entry itself, and children,
  indicating access to the entry's children. ObjectClass names may also be
  specified in this list, which will affect all the attributes that are
  required and/or allowed by that objectClass.

  The last three statements are additive; they can be used in sequence to
  select entities the access rule applies to based on naming context, value
  and attribute type simultaneously.

  The field <who> indicates whom the access rules apply to.  Multiple <who>
  statements can appear in an access control statement, indicating the
  different access privileges to the same resource that apply to different
  accessee.  It can have the forms

	  *
	  anonymous
	  users
	  self

	  dn[.<dnstyle>[,<modifier>]]=<pattern>
	  dnattr=<attrname>
	  group[/<objectclass>[/<attrname>]]
		  [.<style>]=<pattern>
	  peername[.<style>]=<pattern>
	  sockname[.<style>]=<pattern>
	  domain[.<domainstyle>[,<modifier>]]=<pattern>
	  sockurl[.<style>]=<pattern>
	  set[.<style>]=<pattern>

	  ssf=<n>
	  transport_ssf=<n>
	  tls_ssf=<n>
	  sasl_ssf=<n>

	  aci=<attrname>

  They may be specified in combination.

  The wildcard * refers to everybody.

  The keyword anonymous means access is granted to unauthenticated users; it
  is moslty used to limit access to authentication resources (e.g. the
  userPassword attribute) to unauthenticated users for authentication
  purposes.

  The keyword users means access is granted to authenticated users.

  The keyword self means access to an entry is allowed to the entry itself
  (e.g. the entry being accessed and the requesting entry must be the same).

  The statement dn=<pattern> means that access is granted to the matching DN.
  The optional style qualifier dnstyle allows the same choices of the dn form
  of the <what> field.	In addition, the regex form of pattern can exploit
  substring substitution of submatches in the <what> dn.regex clause by using
  the form $<digit>, with digit ranging from 1 to 9.

  The statement dnattr=<attrname> means that access is granted to requests
  whose DN is listed in the entry being accessed under the attrname
  attribute.

  The statement group=<pattern> means that access is granted to requests
  whose DN is listed in the group entry whose DN is given by pattern.  The
  optional parameters objectclass and attrname define the objectClass and the
  member attributeType of the group entry.  The optional style qualifier
  style can be regex, which means that pattern will be expanded accorging to
  regex (7), and base or exact (an alias of base), which means that exact
  match will be used.

  The statements peername=<pattern>, sockname=<pattern>, domain=<pattern>,
  and sockurl=<pattern> mean that the contacting host IP for peername, the
  named pipe file name for sockname, the contacting host name for domain, and
  the contacting URL for sockurl are compared against pattern to determine
  access.  The same style rules for pattern match described for the group
  case apply. The domain clause also allows the subtree style, which succeeds
  when a fully qualified name exactly matches the domain pattern, or its
  trailing part, after a dot, exactly matches the domain pattern.  The domain
  of the contacting host is determined by performing a DNS reverse lookup.
  As this lookup can easily be spoofed, use of the domain statement is
  strongly discouraged.	 By default, reverse lookups are disabled.

  The statement set=<pattern> is undocumented yet.

  The statement aci=<attrname> means that the access control is determined by
  the values in the attrname of the entry itself.  ACIs are experimental;
  they must be enabled at compile time.

  The statements ssf=<n>, transport_ssf=<n>, tls_ssf=<n>, and sasl_ssf=<n>
  set the required Security Strength Factor (ssf) required to grant access.

  The field <access> ::= [self]{<level>|<priv>} determines the access level
  or the specific access privileges the who field will have.  Its component
  are defined as

	  <level> ::= none|auth|compare|search|read|write
	  <priv> ::= {=|+|-}{w|r|s|c|x}+

  The modifier self allows special operations like having a certain access
  level or privilege only in case the operation involves the name of the user
  that's requesting the access.	 It implies the user that requests access is
  bound.  An example is the selfwrite access to the member attribute of a
  group, which allows one to add/delete its own DN from the member list of a
  group, without affecting other members.

  The level access model relies on an incremental interpretation of the
  access privileges.  The possible levels are none, auth, compare, search,
  read, and write.  Each access level implies all the preceding ones, thus
  write access will imply all accesses.	 While none is trivial, auth access
  means that one is allowed access to an attribute to perform
  authentication/authorization operations (e.g.	 bind) with no other access.
  This is useful to grant unauthenticated users the least possible access
  level to critical resources, like passwords.

  The priv access model relies on the explicit setting of access privileges
  for each clause.  The = sign resets previously defined accesses; as a
  consequence, the final access privileges will be only those defined by the
  clause.  The + and - signs add/remove access privileges to the existing
  ones.	 The privileges are w for write, r for read, s for search, c for
  compare, and x for authentication.  More than one privilege can be added in
  one statement.

  The optional field <control> controls the flow of access rule application.
  It can have the forms

	  stop
	  continue
	  break

  where stop, the default, means access checking stops in case of match.  The
  other two forms are used to keep on processing access clauses.  In detail,
  the continue form allows for other <who> clauses in the same <access>
  clause to be considered, so that they may result in incrementally altering
  the privileges, while the break form allows for other <access> clauses that
  match the same target to be processed.  Consider the (silly) example

	  access to dn.subtree="dc=example,dc=com" attrs=cn
		  by * =cs break

	  access to dn.subtree="ou=People,dc=example,dc=com"
		  by * +r

  which allows search and compare privileges to everybody under the
  "dc=example,dc=com" tree, with the second rule allowing also read in the
  "ou=People" subtree, or the (even more silly) example

	  access to dn.subtree="dc=example,dc=com" attrs=cn
		  by * =cs continue
		  by users +r

  which grants everybody search and compare privileges, and adds read
  privileges to authenticated clients.

CAVEATS
  It is strongly recommended to explicitly use the most appropriate DN style,
  to avoid possible incorrect specifications of the access rules as well as
  for performance (avoid unrequired regex matching when an exact match
  suffices) reasons.

  An adminisistrator might create a rule of the form:

	  access to dn="dc=example,dc=com"
		  by ...

  expecting it to match all entries in the subtree "dc=example,dc=com".
  However, this rule actually matches any DN which contains anywhere the
  substring "dc=example,dc=com".  That is, the rule matches both
  "uid=joe,dc=example,dc=com" and "dc=example,dc=com,uid=joe".

  To match the desired subtree, the rule would be more precisely written:

	  access to dn.regex="^(.+,)?dc=example,dc=com$$"
		  by ...

  For performance reasons, it would be better to use the subtree style.

  access to dn.subtree="dc=example,dc=com"
	  by ...

FILES
  /usr/internet/openldap/etc/slapd.conf
       default slapd configuration file

SEE ALSO
  slapd(8),

  "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)

ACKNOWLEDGEMENTS
  OpenLDAP is developed and maintained by The OpenLDAP Project
  (http://www.openldap.org/).  OpenLDAP is derived from University of
  Michigan LDAP 3.3 Release.

Index for Section 5

Alphabetical listing for S

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