1 .TH SLAPD.ACCESS 5 "RELEASEDATE" "OpenLDAP LDVERSION"
2 .\" Copyright 1998-2008 The OpenLDAP Foundation All Rights Reserved.
3 .\" Copying restrictions apply. See COPYRIGHT/LICENSE.
6 slapd.access \- access configuration for slapd, the stand-alone LDAP daemon
12 file contains configuration information for the
14 daemon. This configuration file is also used by the SLAPD tools
26 file consists of a series of global configuration options that apply to
28 as a whole (including all backends), followed by zero or more database
29 backend definitions that contain information specific to a backend
37 # comment - these options apply to every database
38 <global configuration options>
39 # first database definition & configuration options
40 database <backend 1 type>
41 <configuration options specific to backend 1>
42 # subsequent database definitions & configuration options
46 Both the global configuration and each backend-specific section can
47 contain access information. Backend-specific access control
48 directives are used for those entries that belong to the backend,
49 according to their naming context. In case no access control
50 directives are defined for a backend or those which are defined are
51 not applicable, the directives from the global configuration section
54 If no access controls are present, the default policy
55 allows anyone and everyone to read anything but restricts
56 updates to rootdn. (e.g., "access to * by * read").
57 The rootdn can always read and write EVERYTHING!
59 For entries not held in any backend (such as a root DSE), the
60 directives of the first backend (and any global directives) are
63 Arguments that should be replaced by actual text are shown in
65 .SH THE ACCESS DIRECTIVE
66 The structure of the access control directives is
68 .B access to <what> "[ by <who> [ <access> ] [ <control> ] ]+"
69 Grant access (specified by
71 to a set of entries and/or attributes (specified by
73 by one or more requestors (specified by
77 Lists of access directives are evaluated in the order they appear
81 clause matches the datum whose access is being evaluated, its
83 clause list is checked.
86 clause matches the accessor's properties, its
90 clauses are evaluated.
91 Access control checking stops at the first match of the
95 clause, unless otherwise dictated by the
100 clause list is implicitly terminated by a
106 clause that results in stopping the access control with no access
110 clause list is implicitly terminated by a
117 clause that results in granting no access privileges to an otherwise
122 specifies the entity the access control directive applies to.
123 It can have the forms
126 dn[.<dnstyle>]=<dnpattern>
128 attrs=<attrlist>[ val[/matchingRule][.<attrstyle>]=<attrval>]
134 <dnstyle>={{exact|base(object)}|regex
135 |one(level)|sub(tree)|children}
136 <attrlist>={<attr>|[{!|@}]<objectClass>}[,<attrlist>]
137 <attrstyle>={{exact|base(object)}|regex
138 |one(level)|sub(tree)|children}
143 selects the entries based on their naming context.
146 is a string representation of the entry's DN.
149 stands for all the entries, and it is implied if no
155 is optional; however, it is recommended to specify it to avoid ambiguities.
164 indicates the entry whose DN is equal to the
169 indicates all the entries immediately below the
174 indicates all entries in the subtree at the
177 indicates all the entries below (subordinate to) the
186 is a POSIX (''extended'') regular expression pattern,
191 matching a normalized string representation of the entry's DN.
192 The regex form of the pattern does not (yet) support UTF\-8.
195 .B filter=<ldapfilter>
196 selects the entries based on a valid LDAP filter as described in RFC 4515.
205 selects the attributes the access control rule applies to.
206 It is a comma-separated list of attribute types, plus the special names
208 indicating access to the entry itself, and
210 indicating access to the entry's children. ObjectClass names may also
211 be specified in this list, which will affect all the attributes that
212 are required and/or allowed by that objectClass.
217 are directly treated as objectClass names. A name prefixed by
219 is also treated as an objectClass, but in this case the access rule
220 affects the attributes that are not required nor allowed
225 .B attrs=@extensibleObject
226 is implied, i.e. all attributes are addressed.
229 .B attrs=<attr> val[/matchingRule][.<attrstyle>]=<attrval>
230 specifies access to a particular value of a single attribute.
231 In this case, only a single attribute type may be given. The
234 (the default) uses the attribute's equality matching rule to compare the
235 value, unless a different (and compatible) matching rule is specified. If the
239 the provided value is used as a POSIX (''extended'') regular
240 expression pattern. If the attribute has DN syntax, the
248 resulting in base, onelevel, subtree or children match, respectively.
250 The dn, filter, and attrs statements are additive; they can be used in sequence
251 to select entities the access rule applies to based on naming context,
252 value and attribute type simultaneously.
256 indicates whom the access rules apply to.
259 statements can appear in an access control statement, indicating the
260 different access privileges to the same resource that apply to different
262 It can have the forms
270 dn[.<dnstyle>[,<modifier>]]=<DN>
275 realself[.<selfstyle>]
277 realdn[.<dnstyle>[,<modifier>]]=<DN>
278 realdnattr=<attrname>
280 group[/<objectclass>[/<attrname>]]
281 [.<groupstyle>]=<group>
282 peername[.<peernamestyle>]=<peername>
283 sockname[.<style>]=<sockname>
284 domain[.<domainstyle>[,<modifier>]]=<domain>
285 sockurl[.<style>]=<sockurl>
286 set[.<setstyle>]=<pattern>
293 dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
299 <style>={exact|regex|expand}
300 <selfstyle>={level{<n>}}
301 <dnstyle>={{exact|base(object)}|regex
302 |one(level)|sub(tree)|children|level{<n>}}
303 <groupstyle>={exact|expand}
304 <peernamestyle>={<style>|ip|ipv6|path}
305 <domainstyle>={exact|regex|sub(tree)}
306 <setstyle>={exact|regex}
308 <name>=aci <pattern>=<attrname>]
311 They may be specified in combination.
320 The keywords prefixed by
322 act as their counterparts without prefix; the checking respectively occurs
323 with the \fIauthentication\fP DN and the \fIauthorization\fP DN.
327 means access is granted to unauthenticated clients; it is mostly used
328 to limit access to authentication resources (e.g. the
330 attribute) to unauthenticated clients for authentication purposes.
334 means access is granted to authenticated clients.
338 means access to an entry is allowed to the entry itself (e.g. the entry
339 being accessed and the requesting entry must be the same).
342 style, where \fI<n>\fP indicates what ancestor of the DN
343 is to be used in matches.
344 A positive value indicates that the <n>-th ancestor of the user's DN
345 is to be considered; a negative value indicates that the <n>-th ancestor
346 of the target is to be considered.
347 For example, a "\fIby self.level{1} ...\fP" clause would match
348 when the object "\fIdc=example,dc=com\fP" is accessed
349 by "\fIcn=User,dc=example,dc=com\fP".
350 A "\fIby self.level{-1} ...\fP" clause would match when the same user
351 accesses the object "\fIou=Address Book,cn=User,dc=example,dc=com\fP".
355 means that access is granted to the matching DN.
356 The optional style qualifier
358 allows the same choices of the dn form of the
360 field. In addition, the
362 style can exploit substring substitution of submatches in the
364 dn.regex clause by using the form
368 ranging from 0 to 9 (where 0 matches the entire string),
371 for submatches higher than 9.
372 Substring substitution from attribute value can
376 Since the dollar character is used to indicate a substring replacement,
377 the dollar character that is used to indicate match up to the end of
378 the string must be escaped by a second dollar character, e.g.
381 access to dn.regex="^(.+,)?uid=([^,]+),dc=[^,]+,dc=com$"
382 by dn.regex="^uid=$2,dc=[^,]+,dc=com$$" write
388 At present, the only type allowed is
390 which causes substring substitution of submatches to take place
397 dnstyle in the above example may be of use only if the
399 clause needs to be a regex; otherwise, if the
400 value of the second (from the right)
402 portion of the DN in the above example were fixed, the form
405 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
406 by dn.exact,expand="uid=$2,dc=example,dc=com" write
409 could be used; if it had to match the value in the
414 access to dn.regex="^(.+,)?uid=([^,]+),dc=([^,]+),dc=com$"
415 by dn.exact,expand="uid=$2,dc=$3,dc=com" write
422 clause other than regex may provide submatches as well.
433 as the match of the entire string.
442 as the match of the rightmost part of the DN as defined in the
445 This may be useful, for instance, to provide access to all the
446 ancestors of a user by defining
449 access to dn.subtree="dc=com"
450 by dn.subtree,expand="$1" read
453 which means that only access to entries that appear in the DN of the
459 form is an extension and a generalization of the
461 form, which matches all DNs whose <n>-th ancestor is the pattern.
462 So, \fIlevel{1}\fP is equivalent to \fIonelevel\fP,
463 and \fIlevel{0}\fP is equivalent to \fIbase\fP.
465 It is perfectly useless to give any access privileges to a DN
466 that exactly matches the
468 of the database the ACLs apply to, because it implicitly
469 possesses write privileges for the entire tree of that database.
470 Actually, access control is bypassed for the
472 to solve the intrinsic chicken-and-egg problem.
476 means that access is granted to requests whose DN is listed in the
477 entry being accessed under the
483 means that access is granted to requests whose DN is listed
484 in the group entry whose DN is given by
486 The optional parameters
490 define the objectClass and the member attributeType of the group entry.
496 The optional style qualifier
502 will be expanded as a replacement string (but not as a regular expression)
509 which means that exact match will be used.
510 If the style of the DN portion of the
512 clause is regex, the submatches are made available according to
516 other styles provide limited submatches as discussed above about
521 For static groups, the specified attributeType must have
524 .B NameAndOptionalUID
525 syntax. For dynamic groups the attributeType must
528 attributeType. Only LDAP URIs of the form
529 .B ldap:///<base>??<scope>?<filter>
530 will be evaluated in a dynamic group, by searching the local server only.
533 .BR peername=<peername> ,
534 .BR sockname=<sockname> ,
535 .BR domain=<domain> ,
537 .BR sockurl=<sockurl>
538 mean that the contacting host IP (in the form
541 .BR "IP=[<ipv6>]:<port>"
543 or the contacting host named pipe file name (in the form
545 if connecting through a named pipe) for
547 the named pipe file name for
549 the contacting host name for
551 and the contacting URL for
558 rules for pattern match described for the
562 style, which implies submatch
564 and regex match of the corresponding connection parameters.
569 clause (the default) implies a case-exact match on the client's
573 prefix and the trailing
579 prefix if connecting through a named pipe.
582 style interprets the pattern as
583 .BR <peername>=<ip>[%<mask>][{<n>}] ,
588 are dotted digit representations of the IP and the mask, while
590 delimited by curly brackets, is an optional port.
591 The same applies to IPv6 addresses when the special
594 When checking access privileges, the IP portion of the
596 is extracted, eliminating the
600 part, and it is compared against the
602 portion of the pattern after masking with
604 \fI((peername & <mask>) == <ip>)\fP.
606 .B peername.ip=127.0.0.1
609 allow connections only from localhost,
610 .B peername.ip=192.168.1.0%255.255.255.0
611 allows connections from any IP in the 192.168.1 class C domain, and
612 .B peername.ip=192.168.1.16%255.255.255.240{9009}
613 allows connections from any IP in the 192.168.1.[16-31] range
614 of the same domain, only if port 9009 is used.
621 when connecting through a named pipe, and performs an exact match
622 on the given pattern.
625 clause also allows the
627 style, which succeeds when a fully qualified name exactly matches the
629 pattern, or its trailing part, after a
636 style is allowed, implying an
638 match with submatch expansion; the use of
640 as a style modifier is considered more appropriate.
642 .B domain.subtree=example.com
643 will match www.example.com, but will not match www.anotherexample.com.
646 of the contacting host is determined by performing a DNS reverse lookup.
647 As this lookup can easily be spoofed, use of the
649 statement is strongly discouraged. By default, reverse lookups are disabled.
656 option; the only value currently supported is
658 which causes substring substitution of submatches to take place even if
663 much like the analogous usage in
672 .B dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
673 means that access checking is delegated to the admin-defined method
676 which can be registered at run-time by means of the
684 are optional, and are directly passed to the registered parsing routine.
685 Dynacl is experimental; it must be enabled at compile time.
688 .B dynacl/aci[=<attrname>]
689 means that the access control is determined by the values in the
694 indicates what attributeType holds the ACI information in the entry.
697 operational attribute is used.
698 ACIs are experimental; they must be enabled at compile time.
702 .BR transport_ssf=<n> ,
706 set the minimum required Security Strength Factor (ssf) needed
707 to grant access. The value should be positive integer.
708 .SH THE <ACCESS> FIELD
710 .B <access> ::= [[real]self]{<level>|<priv>}
711 determines the access level or the specific access privileges the
714 Its component are defined as
717 <level> ::= none|disclose|auth|compare|search|read|{write|add|delete}|manage
718 <priv> ::= {=|+|-}{0|d|x|c|s|r|{w|a|z}|m}+
723 allows special operations like having a certain access level or privilege
724 only in case the operation involves the name of the user that's requesting
726 It implies the user that requests access is authorized.
729 refers to the authenticated DN as opposed to the authorized DN of the
734 access to the member attribute of a group, which allows one to add/delete
735 its own DN from the member list of a group, while being not allowed
736 to affect other members.
740 access model relies on an incremental interpretation of the access
742 The possible levels are
752 Each access level implies all the preceding ones, thus
754 grants all access including administrative access.
757 access is actually the combination of
761 which respectively restrict the write privilege to add or delete
768 access level disallows all access including disclosure on error.
772 access level allows disclosure of information on error.
776 access level means that one is allowed access to an attribute to perform
777 authentication/authorization operations (e.g.
779 with no other access.
780 This is useful to grant unauthenticated clients the least possible
781 access level to critical resources, like passwords.
785 access model relies on the explicit setting of access privileges
789 sign resets previously defined accesses; as a consequence, the final
790 access privileges will be only those defined by the clause.
795 signs add/remove access privileges to the existing ones.
812 for authentication, and
815 More than one of the above privileges can be added in one statement.
817 indicates no privileges and is used only by itself (e.g., +0).
823 If no access is given, it defaults to
825 .SH THE <CONTROL> FIELD
828 controls the flow of access rule application.
829 It can have the forms
839 the default, means access checking stops in case of match.
840 The other two forms are used to keep on processing access clauses.
843 form allows for other
847 clause to be considered, so that they may result in incrementally altering
848 the privileges, while the
850 form allows for other
852 clauses that match the same target to be processed.
853 Consider the (silly) example
856 access to dn.subtree="dc=example,dc=com" attrs=cn
859 access to dn.subtree="ou=People,dc=example,dc=com"
863 which allows search and compare privileges to everybody under
864 the "dc=example,dc=com" tree, with the second rule allowing
865 also read in the "ou=People" subtree,
866 or the (even more silly) example
869 access to dn.subtree="dc=example,dc=com" attrs=cn
874 which grants everybody search and compare privileges, and adds read
875 privileges to authenticated clients.
877 One useful application is to easily grant write privileges to an
879 that is different from the
881 In this case, since the
883 needs write access to (almost) all data, one can use
887 by dn.exact="cn=The Update DN,dc=example,dc=com" write
891 as the first access rule.
892 As a consequence, unless the operation is performed with the
894 identity, control is passed straight to the subsequent rules.
896 .SH OPERATION REQUIREMENTS
897 Operations require different privileges on different portions of entries.
898 The following summary applies to primary database backends such as
899 the BDB and HDB backends. Requirements for other backends may
900 (and often do) differ.
907 privileges on the pseudo-attribute
909 of the entry being added, and
911 privileges on the pseudo-attribute
913 of the entry's parent.
914 When adding the suffix entry of a database,
918 of the empty DN ("") is required. Also if
919 Add content ACL checking has been configured on
920 the database (see the
926 will be required on all of the attributes being added.
931 operation, when credentials are stored in the directory, requires
933 privileges on the attribute the credentials are stored in (usually
941 privileges on the attribute that is being compared.
948 privileges on the pseudo-attribute
950 of the entry being deleted, and
954 pseudo-attribute of the entry's parent.
961 privileges on the attributes being modified.
964 is required to add new values,
966 is required to delete existing values,
973 are required to replace existing values.
980 privileges on the pseudo-attribute
982 of the entry whose relative DN is being modified,
984 privileges on the pseudo-attribute
986 of the old entry's parents,
988 privileges on the pseudo-attribute
990 of the new entry's parents, and
992 privileges on the attributes that are present in the new relative DN.
994 privileges are also required on the attributes that are present
995 in the old relative DN if
1006 pseudo-attribute of the searchBase
1007 (NOTE: this was introduced with OpenLDAP 2.4).
1008 Then, for each entry, it requires
1010 privileges on the attributes that are defined in the filter.
1011 The resulting entries are finally tested for
1013 privileges on the pseudo-attribute
1015 (for read access to the entry itself)
1018 access on each value of each attribute that is requested.
1021 object used in generating continuation references, the operation requires
1023 access on the pseudo-attribute
1025 (for read access to the referral object itself),
1028 access to the attribute holding the referral information
1034 Some internal operations and some
1036 require specific access privileges.
1043 privileges on all the attributes that are present in the search filter
1044 of the URI regexp maps (the right-hand side of the
1048 privileges are also required on the
1050 attribute of the authorizing identity and/or on the
1052 attribute of the authorized identity.
1053 In general, when an internal lookup is performed for authentication
1054 or authorization purposes, search-specific privileges (see the access
1055 requirements for the search operation illustrated above) are relaxed to
1059 Access control to search entries is checked by the frontend,
1060 so it is fully honored by all backends; for all other operations
1061 and for the discovery phase of the search operation,
1062 full ACL semantics is only supported by the primary backends, i.e.
1067 Some other backend, like
1069 may fully support them; others may only support a portion of the
1070 described semantics, or even differ in some aspects.
1071 The relevant details are described in the backend-specific man pages.
1074 It is strongly recommended to explicitly use the most appropriate
1080 clauses, to avoid possible incorrect specifications of the access rules
1081 as well as for performance (avoid unnecessary regex matching when an exact
1082 match suffices) reasons.
1084 An administrator might create a rule of the form:
1087 access to dn.regex="dc=example,dc=com"
1091 expecting it to match all entries in the subtree "dc=example,dc=com".
1092 However, this rule actually matches any DN which contains anywhere
1093 the substring "dc=example,dc=com". That is, the rule matches both
1094 "uid=joe,dc=example,dc=com" and "dc=example,dc=com,uid=joe".
1096 To match the desired subtree, the rule would be more precisely
1100 access to dn.regex="^(.+,)?dc=example,dc=com$"
1104 For performance reasons, it would be better to use the subtree style.
1107 access to dn.subtree="dc=example,dc=com"
1111 When writing submatch rules, it may be convenient to avoid unnecessary
1114 use; for instance, to allow access to the subtree of the user
1117 clause, one could use
1120 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1121 by dn.regex="^uid=$2,dc=example,dc=com$$" write
1125 However, since all that is required in the
1127 clause is substring expansion, a more efficient solution is
1130 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1131 by dn.exact,expand="uid=$2,dc=example,dc=com" write
1139 implies substring expansion,
1141 as well as all the other DN specific
1143 values, does not, so it must be explicitly requested.
1148 default slapd configuration file
1156 "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
1157 .SH ACKNOWLEDGEMENTS