1 .TH SLAPD.ACCESS 5 "RELEASEDATE" "OpenLDAP LDVERSION"
2 .\" Copyright 1998-2009 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").
58 When dealing with an access list, because the global access list is
59 effectively appended to each per-database list, if the resulting
60 list is non-empty then the access list will end with an implicit
61 .B access to * by * none
62 directive. If there are no access directives applicable to a backend,
63 then a default read is used.
65 .B Be warned: the rootdn can always read and write EVERYTHING!
67 For entries not held in any backend (such as a root DSE), the
68 global directives are used.
70 Arguments that should be replaced by actual text are shown in
72 .SH THE ACCESS DIRECTIVE
73 The structure of the access control directives is
75 .B access to <what> "[ by <who> [ <access> ] [ <control> ] ]+"
76 Grant access (specified by
78 to a set of entries and/or attributes (specified by
80 by one or more requestors (specified by
84 Lists of access directives are evaluated in the order they appear
88 clause matches the datum whose access is being evaluated, its
90 clause list is checked.
93 clause matches the accessor's properties, its
97 clauses are evaluated.
98 Access control checking stops at the first match of the
102 clause, unless otherwise dictated by the
107 clause list is implicitly terminated by a
113 clause that results in stopping the access control with no access
117 clause list is implicitly terminated by a
124 clause that results in granting no access privileges to an otherwise
129 specifies the entity the access control directive applies to.
130 It can have the forms
133 dn[.<dnstyle>]=<dnpattern>
135 attrs=<attrlist>[ val[/matchingRule][.<attrstyle>]=<attrval>]
141 <dnstyle>={{exact|base(object)}|regex
142 |one(level)|sub(tree)|children}
143 <attrlist>={<attr>|[{!|@}]<objectClass>}[,<attrlist>]
144 <attrstyle>={{exact|base(object)}|regex
145 |one(level)|sub(tree)|children}
150 selects the entries based on their naming context.
153 is a string representation of the entry's DN.
156 stands for all the entries, and it is implied if no
162 is optional; however, it is recommended to specify it to avoid ambiguities.
171 indicates the entry whose DN is equal to the
176 indicates all the entries immediately below the
181 indicates all entries in the subtree at the
184 indicates all the entries below (subordinate to) the
193 is a POSIX (''extended'') regular expression pattern,
198 matching a normalized string representation of the entry's DN.
199 The regex form of the pattern does not (yet) support UTF-8.
202 .B filter=<ldapfilter>
203 selects the entries based on a valid LDAP filter as described in RFC 4515.
212 selects the attributes the access control rule applies to.
213 It is a comma-separated list of attribute types, plus the special names
215 indicating access to the entry itself, and
217 indicating access to the entry's children. ObjectClass names may also
218 be specified in this list, which will affect all the attributes that
219 are required and/or allowed by that objectClass.
224 are directly treated as objectClass names. A name prefixed by
226 is also treated as an objectClass, but in this case the access rule
227 affects the attributes that are not required nor allowed
232 .B attrs=@extensibleObject
233 is implied, i.e. all attributes are addressed.
236 .B attrs=<attr> val[/matchingRule][.<attrstyle>]=<attrval>
237 specifies access to a particular value of a single attribute.
238 In this case, only a single attribute type may be given. The
241 (the default) uses the attribute's equality matching rule to compare the
242 value, unless a different (and compatible) matching rule is specified. If the
246 the provided value is used as a POSIX (''extended'') regular
247 expression pattern. If the attribute has DN syntax, the
255 resulting in base, onelevel, subtree or children match, respectively.
257 The dn, filter, and attrs statements are additive; they can be used in sequence
258 to select entities the access rule applies to based on naming context,
259 value and attribute type simultaneously.
263 indicates whom the access rules apply to.
266 statements can appear in an access control statement, indicating the
267 different access privileges to the same resource that apply to different
269 It can have the forms
277 dn[.<dnstyle>[,<modifier>]]=<DN>
282 realself[.<selfstyle>]
284 realdn[.<dnstyle>[,<modifier>]]=<DN>
285 realdnattr=<attrname>
287 group[/<objectclass>[/<attrname>]]
288 [.<groupstyle>]=<group>
289 peername[.<peernamestyle>]=<peername>
290 sockname[.<style>]=<sockname>
291 domain[.<domainstyle>[,<modifier>]]=<domain>
292 sockurl[.<style>]=<sockurl>
293 set[.<setstyle>]=<pattern>
300 dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
306 <style>={exact|regex|expand}
307 <selfstyle>={level{<n>}}
308 <dnstyle>={{exact|base(object)}|regex
309 |one(level)|sub(tree)|children|level{<n>}}
310 <groupstyle>={exact|expand}
311 <peernamestyle>={<style>|ip|ipv6|path}
312 <domainstyle>={exact|regex|sub(tree)}
313 <setstyle>={exact|expand}
315 <name>=aci <pattern>=<attrname>]
318 They may be specified in combination.
327 The keywords prefixed by
329 act as their counterparts without prefix; the checking respectively occurs
330 with the \fIauthentication\fP DN and the \fIauthorization\fP DN.
334 means access is granted to unauthenticated clients; it is mostly used
335 to limit access to authentication resources (e.g. the
337 attribute) to unauthenticated clients for authentication purposes.
341 means access is granted to authenticated clients.
345 means access to an entry is allowed to the entry itself (e.g. the entry
346 being accessed and the requesting entry must be the same).
349 style, where \fI<n>\fP indicates what ancestor of the DN
350 is to be used in matches.
351 A positive value indicates that the <n>-th ancestor of the user's DN
352 is to be considered; a negative value indicates that the <n>-th ancestor
353 of the target is to be considered.
354 For example, a "\fIby self.level{1} ...\fP" clause would match
355 when the object "\fIdc=example,dc=com\fP" is accessed
356 by "\fIcn=User,dc=example,dc=com\fP".
357 A "\fIby self.level{-1} ...\fP" clause would match when the same user
358 accesses the object "\fIou=Address Book,cn=User,dc=example,dc=com\fP".
362 means that access is granted to the matching DN.
363 The optional style qualifier
365 allows the same choices of the dn form of the
367 field. In addition, the
369 style can exploit substring substitution of submatches in the
371 dn.regex clause by using the form
375 ranging from 0 to 9 (where 0 matches the entire string),
378 for submatches higher than 9.
379 Substring substitution from attribute value can
383 Since the dollar character is used to indicate a substring replacement,
384 the dollar character that is used to indicate match up to the end of
385 the string must be escaped by a second dollar character, e.g.
388 access to dn.regex="^(.+,)?uid=([^,]+),dc=[^,]+,dc=com$"
389 by dn.regex="^uid=$2,dc=[^,]+,dc=com$$" write
395 At present, the only type allowed is
397 which causes substring substitution of submatches to take place
404 dnstyle in the above example may be of use only if the
406 clause needs to be a regex; otherwise, if the
407 value of the second (from the right)
409 portion of the DN in the above example were fixed, the form
412 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
413 by dn.exact,expand="uid=$2,dc=example,dc=com" write
416 could be used; if it had to match the value in the
421 access to dn.regex="^(.+,)?uid=([^,]+),dc=([^,]+),dc=com$"
422 by dn.exact,expand="uid=$2,dc=$3,dc=com" write
429 clause other than regex may provide submatches as well.
440 as the match of the entire string.
449 as the match of the rightmost part of the DN as defined in the
452 This may be useful, for instance, to provide access to all the
453 ancestors of a user by defining
456 access to dn.subtree="dc=com"
457 by dn.subtree,expand="$1" read
460 which means that only access to entries that appear in the DN of the
466 form is an extension and a generalization of the
468 form, which matches all DNs whose <n>-th ancestor is the pattern.
469 So, \fIlevel{1}\fP is equivalent to \fIonelevel\fP,
470 and \fIlevel{0}\fP is equivalent to \fIbase\fP.
472 It is perfectly useless to give any access privileges to a DN
473 that exactly matches the
475 of the database the ACLs apply to, because it implicitly
476 possesses write privileges for the entire tree of that database.
477 Actually, access control is bypassed for the
479 to solve the intrinsic chicken-and-egg problem.
483 means that access is granted to requests whose DN is listed in the
484 entry being accessed under the
490 means that access is granted to requests whose DN is listed
491 in the group entry whose DN is given by
493 The optional parameters
497 define the objectClass and the member attributeType of the group entry.
503 The optional style qualifier
509 will be expanded as a replacement string (but not as a regular expression)
516 which means that exact match will be used.
517 If the style of the DN portion of the
519 clause is regex, the submatches are made available according to
523 other styles provide limited submatches as discussed above about
528 For static groups, the specified attributeType must have
531 .B NameAndOptionalUID
532 syntax. For dynamic groups the attributeType must
535 attributeType. Only LDAP URIs of the form
536 .B ldap:///<base>??<scope>?<filter>
537 will be evaluated in a dynamic group, by searching the local server only.
540 .BR peername=<peername> ,
541 .BR sockname=<sockname> ,
542 .BR domain=<domain> ,
544 .BR sockurl=<sockurl>
545 mean that the contacting host IP (in the form
548 .BR "IP=[<ipv6>]:<port>"
550 or the contacting host named pipe file name (in the form
552 if connecting through a named pipe) for
554 the named pipe file name for
556 the contacting host name for
558 and the contacting URL for
565 rules for pattern match described for the
569 style, which implies submatch
571 and regex match of the corresponding connection parameters.
576 clause (the default) implies a case-exact match on the client's
580 prefix and the trailing
586 prefix if connecting through a named pipe.
589 style interprets the pattern as
590 .BR <peername>=<ip>[%<mask>][{<n>}] ,
595 are dotted digit representations of the IP and the mask, while
597 delimited by curly brackets, is an optional port.
598 The same applies to IPv6 addresses when the special
601 When checking access privileges, the IP portion of the
603 is extracted, eliminating the
607 part, and it is compared against the
609 portion of the pattern after masking with
611 \fI((peername & <mask>) == <ip>)\fP.
613 .B peername.ip=127.0.0.1
616 allow connections only from localhost,
617 .B peername.ip=192.168.1.0%255.255.255.0
618 allows connections from any IP in the 192.168.1 class C domain, and
619 .B peername.ip=192.168.1.16%255.255.255.240{9009}
620 allows connections from any IP in the 192.168.1.[16-31] range
621 of the same domain, only if port 9009 is used.
628 when connecting through a named pipe, and performs an exact match
629 on the given pattern.
632 clause also allows the
634 style, which succeeds when a fully qualified name exactly matches the
636 pattern, or its trailing part, after a
643 style is allowed, implying an
645 match with submatch expansion; the use of
647 as a style modifier is considered more appropriate.
649 .B domain.subtree=example.com
650 will match www.example.com, but will not match www.anotherexample.com.
653 of the contacting host is determined by performing a DNS reverse lookup.
654 As this lookup can easily be spoofed, use of the
656 statement is strongly discouraged. By default, reverse lookups are disabled.
663 option; the only value currently supported is
665 which causes substring substitution of submatches to take place even if
670 much like the analogous usage in
679 .B dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
680 means that access checking is delegated to the admin-defined method
683 which can be registered at run-time by means of the
691 are optional, and are directly passed to the registered parsing routine.
692 Dynacl is experimental; it must be enabled at compile time.
695 .B dynacl/aci[=<attrname>]
696 means that the access control is determined by the values in the
701 indicates what attributeType holds the ACI information in the entry.
704 operational attribute is used.
705 ACIs are experimental; they must be enabled at compile time.
709 .BR transport_ssf=<n> ,
713 set the minimum required Security Strength Factor (ssf) needed
714 to grant access. The value should be positive integer.
715 .SH THE <ACCESS> FIELD
717 .B <access> ::= [[real]self]{<level>|<priv>}
718 determines the access level or the specific access privileges the
721 Its component are defined as
724 <level> ::= none|disclose|auth|compare|search|read|{write|add|delete}|manage
725 <priv> ::= {=|+|\-}{0|d|x|c|s|r|{w|a|z}|m}+
730 allows special operations like having a certain access level or privilege
731 only in case the operation involves the name of the user that's requesting
733 It implies the user that requests access is authorized.
736 refers to the authenticated DN as opposed to the authorized DN of the
741 access to the member attribute of a group, which allows one to add/delete
742 its own DN from the member list of a group, while being not allowed
743 to affect other members.
747 access model relies on an incremental interpretation of the access
749 The possible levels are
759 Each access level implies all the preceding ones, thus
761 grants all access including administrative access.
764 access is actually the combination of
768 which respectively restrict the write privilege to add or delete
775 access level disallows all access including disclosure on error.
779 access level allows disclosure of information on error.
783 access level means that one is allowed access to an attribute to perform
784 authentication/authorization operations (e.g.
786 with no other access.
787 This is useful to grant unauthenticated clients the least possible
788 access level to critical resources, like passwords.
792 access model relies on the explicit setting of access privileges
796 sign resets previously defined accesses; as a consequence, the final
797 access privileges will be only those defined by the clause.
802 signs add/remove access privileges to the existing ones.
819 for authentication, and
822 More than one of the above privileges can be added in one statement.
824 indicates no privileges and is used only by itself (e.g., +0).
830 If no access is given, it defaults to
832 .SH THE <CONTROL> FIELD
835 controls the flow of access rule application.
836 It can have the forms
846 the default, means access checking stops in case of match.
847 The other two forms are used to keep on processing access clauses.
850 form allows for other
854 clause to be considered, so that they may result in incrementally altering
855 the privileges, while the
857 form allows for other
859 clauses that match the same target to be processed.
860 Consider the (silly) example
863 access to dn.subtree="dc=example,dc=com" attrs=cn
866 access to dn.subtree="ou=People,dc=example,dc=com"
870 which allows search and compare privileges to everybody under
871 the "dc=example,dc=com" tree, with the second rule allowing
872 also read in the "ou=People" subtree,
873 or the (even more silly) example
876 access to dn.subtree="dc=example,dc=com" attrs=cn
881 which grants everybody search and compare privileges, and adds read
882 privileges to authenticated clients.
884 One useful application is to easily grant write privileges to an
886 that is different from the
888 In this case, since the
890 needs write access to (almost) all data, one can use
894 by dn.exact="cn=The Update DN,dc=example,dc=com" write
898 as the first access rule.
899 As a consequence, unless the operation is performed with the
901 identity, control is passed straight to the subsequent rules.
903 .SH OPERATION REQUIREMENTS
904 Operations require different privileges on different portions of entries.
905 The following summary applies to primary database backends such as
906 the BDB and HDB backends. Requirements for other backends may
907 (and often do) differ.
914 privileges on the pseudo-attribute
916 of the entry being added, and
918 privileges on the pseudo-attribute
920 of the entry's parent.
921 When adding the suffix entry of a database,
925 of the empty DN ("") is required. Also if
926 Add content ACL checking has been configured on
927 the database (see the
930 .BR slapd\-config (5)
933 will be required on all of the attributes being added.
938 operation, when credentials are stored in the directory, requires
940 privileges on the attribute the credentials are stored in (usually
948 privileges on the attribute that is being compared.
955 privileges on the pseudo-attribute
957 of the entry being deleted, and
961 pseudo-attribute of the entry's parent.
968 privileges on the attributes being modified.
971 is required to add new values,
973 is required to delete existing values,
980 are required to replace existing values.
987 privileges on the pseudo-attribute
989 of the entry whose relative DN is being modified,
991 privileges on the pseudo-attribute
993 of the old entry's parents,
995 privileges on the pseudo-attribute
997 of the new entry's parents, and
999 privileges on the attributes that are present in the new relative DN.
1001 privileges are also required on the attributes that are present
1002 in the old relative DN if
1013 pseudo-attribute of the searchBase
1014 (NOTE: this was introduced with OpenLDAP 2.4).
1015 Then, for each entry, it requires
1017 privileges on the attributes that are defined in the filter.
1018 The resulting entries are finally tested for
1020 privileges on the pseudo-attribute
1022 (for read access to the entry itself)
1025 access on each value of each attribute that is requested.
1028 object used in generating continuation references, the operation requires
1030 access on the pseudo-attribute
1032 (for read access to the referral object itself),
1035 access to the attribute holding the referral information
1041 Some internal operations and some
1043 require specific access privileges.
1050 privileges on all the attributes that are present in the search filter
1051 of the URI regexp maps (the right-hand side of the
1055 privileges are also required on the
1057 attribute of the authorizing identity and/or on the
1059 attribute of the authorized identity.
1060 In general, when an internal lookup is performed for authentication
1061 or authorization purposes, search-specific privileges (see the access
1062 requirements for the search operation illustrated above) are relaxed to
1066 Access control to search entries is checked by the frontend,
1067 so it is fully honored by all backends; for all other operations
1068 and for the discovery phase of the search operation,
1069 full ACL semantics is only supported by the primary backends, i.e.
1074 Some other backend, like
1076 may fully support them; others may only support a portion of the
1077 described semantics, or even differ in some aspects.
1078 The relevant details are described in the backend-specific man pages.
1081 It is strongly recommended to explicitly use the most appropriate
1087 clauses, to avoid possible incorrect specifications of the access rules
1088 as well as for performance (avoid unnecessary regex matching when an exact
1089 match suffices) reasons.
1091 An administrator might create a rule of the form:
1094 access to dn.regex="dc=example,dc=com"
1098 expecting it to match all entries in the subtree "dc=example,dc=com".
1099 However, this rule actually matches any DN which contains anywhere
1100 the substring "dc=example,dc=com". That is, the rule matches both
1101 "uid=joe,dc=example,dc=com" and "dc=example,dc=com,uid=joe".
1103 To match the desired subtree, the rule would be more precisely
1107 access to dn.regex="^(.+,)?dc=example,dc=com$"
1111 For performance reasons, it would be better to use the subtree style.
1114 access to dn.subtree="dc=example,dc=com"
1118 When writing submatch rules, it may be convenient to avoid unnecessary
1121 use; for instance, to allow access to the subtree of the user
1124 clause, one could use
1127 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1128 by dn.regex="^uid=$2,dc=example,dc=com$$" write
1132 However, since all that is required in the
1134 clause is substring expansion, a more efficient solution is
1137 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1138 by dn.exact,expand="uid=$2,dc=example,dc=com" write
1146 implies substring expansion,
1148 as well as all the other DN specific
1150 values, does not, so it must be explicitly requested.
1155 default slapd configuration file
1163 "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
1164 .SH ACKNOWLEDGEMENTS
projects / openldap / blob