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 Since the dollar character is used to indicate a substring replacement,
373 the dollar character that is used to indicate match up to the end of
374 the string must be escaped by a second dollar character, e.g.
377 access to dn.regex="^(.+,)?uid=([^,]+),dc=[^,]+,dc=com$"
378 by dn.regex="^uid=$2,dc=[^,]+,dc=com$$" write
384 At present, the only type allowed is
386 which causes substring substitution of submatches to take place
393 dnstyle in the above example may be of use only if the
395 clause needs to be a regex; otherwise, if the
396 value of the second (from the right)
398 portion of the DN in the above example were fixed, the form
401 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
402 by dn.exact,expand="uid=$2,dc=example,dc=com" write
405 could be used; if it had to match the value in the
410 access to dn.regex="^(.+,)?uid=([^,]+),dc=([^,]+),dc=com$"
411 by dn.exact,expand="uid=$2,dc=$3,dc=com" write
418 clause other than regex may provide submatches as well.
429 as the match of the entire string.
438 as the match of the rightmost part of the DN as defined in the
441 This may be useful, for instance, to provide access to all the
442 ancestors of a user by defining
445 access to dn.subtree="dc=com"
446 by dn.subtree,expand="$1" read
449 which means that only access to entries that appear in the DN of the
455 form is an extension and a generalization of the
457 form, which matches all DNs whose <n>-th ancestor is the pattern.
458 So, \fIlevel{1}\fP is equivalent to \fIonelevel\fP,
459 and \fIlevel{0}\fP is equivalent to \fIbase\fP.
461 It is perfectly useless to give any access privileges to a DN
462 that exactly matches the
464 of the database the ACLs apply to, because it implicitly
465 possesses write privileges for the entire tree of that database.
466 Actually, access control is bypassed for the
468 to solve the intrinsic chicken-and-egg problem.
472 means that access is granted to requests whose DN is listed in the
473 entry being accessed under the
479 means that access is granted to requests whose DN is listed
480 in the group entry whose DN is given by
482 The optional parameters
486 define the objectClass and the member attributeType of the group entry.
492 The optional style qualifier
498 will be expanded as a replacement string (but not as a regular expression)
505 which means that exact match will be used.
506 If the style of the DN portion of the
508 clause is regex, the submatches are made available according to
512 other styles provide limited submatches as discussed above about
517 For static groups, the specified attributeType must have
520 .B NameAndOptionalUID
521 syntax. For dynamic groups the attributeType must
524 attributeType. Only LDAP URIs of the form
525 .B ldap:///<base>??<scope>?<filter>
526 will be evaluated in a dynamic group, by searching the local server only.
529 .BR peername=<peername> ,
530 .BR sockname=<sockname> ,
531 .BR domain=<domain> ,
533 .BR sockurl=<sockurl>
534 mean that the contacting host IP (in the form
537 .BR "IP=[<ipv6>]:<port>"
539 or the contacting host named pipe file name (in the form
541 if connecting through a named pipe) for
543 the named pipe file name for
545 the contacting host name for
547 and the contacting URL for
554 rules for pattern match described for the
558 style, which implies submatch
560 and regex match of the corresponding connection parameters.
565 clause (the default) implies a case-exact match on the client's
569 prefix and the trailing
575 prefix if connecting through a named pipe.
578 style interprets the pattern as
579 .BR <peername>=<ip>[%<mask>][{<n>}] ,
584 are dotted digit representations of the IP and the mask, while
586 delimited by curly brackets, is an optional port.
587 The same applies to IPv6 addresses when the special
590 When checking access privileges, the IP portion of the
592 is extracted, eliminating the
596 part, and it is compared against the
598 portion of the pattern after masking with
600 \fI((peername & <mask>) == <ip>)\fP.
602 .B peername.ip=127.0.0.1
605 allow connections only from localhost,
606 .B peername.ip=192.168.1.0%255.255.255.0
607 allows connections from any IP in the 192.168.1 class C domain, and
608 .B peername.ip=192.168.1.16%255.255.255.240{9009}
609 allows connections from any IP in the 192.168.1.[16-31] range
610 of the same domain, only if port 9009 is used.
617 when connecting through a named pipe, and performs an exact match
618 on the given pattern.
621 clause also allows the
623 style, which succeeds when a fully qualified name exactly matches the
625 pattern, or its trailing part, after a
632 style is allowed, implying an
634 match with submatch expansion; the use of
636 as a style modifier is considered more appropriate.
638 .B domain.subtree=example.com
639 will match www.example.com, but will not match www.anotherexample.com.
642 of the contacting host is determined by performing a DNS reverse lookup.
643 As this lookup can easily be spoofed, use of the
645 statement is strongly discouraged. By default, reverse lookups are disabled.
652 option; the only value currently supported is
654 which causes substring substitution of submatches to take place even if
659 much like the analogous usage in
668 .B dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
669 means that access checking is delegated to the admin-defined method
672 which can be registered at run-time by means of the
680 are optional, and are directly passed to the registered parsing routine.
681 Dynacl is experimental; it must be enabled at compile time.
684 .B dynacl/aci[=<attrname>]
685 means that the access control is determined by the values in the
690 indicates what attributeType holds the ACI information in the entry.
693 operational attribute is used.
694 ACIs are experimental; they must be enabled at compile time.
698 .BR transport_ssf=<n> ,
702 set the minimum required Security Strength Factor (ssf) needed
703 to grant access. The value should be positive integer.
704 .SH THE <ACCESS> FIELD
706 .B <access> ::= [[real]self]{<level>|<priv>}
707 determines the access level or the specific access privileges the
710 Its component are defined as
713 <level> ::= none|disclose|auth|compare|search|read|{write|add|delete}|manage
714 <priv> ::= {=|+|-}{0|d|x|c|s|r|{w|a|z}|m}+
719 allows special operations like having a certain access level or privilege
720 only in case the operation involves the name of the user that's requesting
722 It implies the user that requests access is authorized.
725 refers to the authenticated DN as opposed to the authorized DN of the
730 access to the member attribute of a group, which allows one to add/delete
731 its own DN from the member list of a group, while being not allowed
732 to affect other members.
736 access model relies on an incremental interpretation of the access
738 The possible levels are
748 Each access level implies all the preceding ones, thus
750 grants all access including administrative access.
753 access is actually the combination of
757 which respectively restrict the write privilege to add or delete
764 access level disallows all access including disclosure on error.
768 access level allows disclosure of information on error.
772 access level means that one is allowed access to an attribute to perform
773 authentication/authorization operations (e.g.
775 with no other access.
776 This is useful to grant unauthenticated clients the least possible
777 access level to critical resources, like passwords.
781 access model relies on the explicit setting of access privileges
785 sign resets previously defined accesses; as a consequence, the final
786 access privileges will be only those defined by the clause.
791 signs add/remove access privileges to the existing ones.
808 for authentication, and
811 More than one of the above privileges can be added in one statement.
813 indicates no privileges and is used only by itself (e.g., +0).
819 If no access is given, it defaults to
821 .SH THE <CONTROL> FIELD
824 controls the flow of access rule application.
825 It can have the forms
835 the default, means access checking stops in case of match.
836 The other two forms are used to keep on processing access clauses.
839 form allows for other
843 clause to be considered, so that they may result in incrementally altering
844 the privileges, while the
846 form allows for other
848 clauses that match the same target to be processed.
849 Consider the (silly) example
852 access to dn.subtree="dc=example,dc=com" attrs=cn
855 access to dn.subtree="ou=People,dc=example,dc=com"
859 which allows search and compare privileges to everybody under
860 the "dc=example,dc=com" tree, with the second rule allowing
861 also read in the "ou=People" subtree,
862 or the (even more silly) example
865 access to dn.subtree="dc=example,dc=com" attrs=cn
870 which grants everybody search and compare privileges, and adds read
871 privileges to authenticated clients.
873 One useful application is to easily grant write privileges to an
875 that is different from the
877 In this case, since the
879 needs write access to (almost) all data, one can use
883 by dn.exact="cn=The Update DN,dc=example,dc=com" write
887 as the first access rule.
888 As a consequence, unless the operation is performed with the
890 identity, control is passed straight to the subsequent rules.
892 .SH OPERATION REQUIREMENTS
893 Operations require different privileges on different portions of entries.
894 The following summary applies to primary database backends such as
895 the BDB and HDB backends. Requirements for other backends may
896 (and often do) differ.
903 privileges on the pseudo-attribute
905 of the entry being added, and
907 privileges on the pseudo-attribute
909 of the entry's parent.
910 When adding the suffix entry of a database,
914 of the empty DN ("") is required.
919 operation, when credentials are stored in the directory, requires
921 privileges on the attribute the credentials are stored in (usually
929 privileges on the attribute that is being compared.
936 privileges on the pseudo-attribute
938 of the entry being deleted, and
942 pseudo-attribute of the entry's parent.
949 privileges on the attributes being modified.
952 is required to add new values,
954 is required to delete existing values,
961 are required to replace existing values.
968 privileges on the pseudo-attribute
970 of the entry whose relative DN is being modified,
972 privileges on the pseudo-attribute
974 of the old entry's parents,
976 privileges on the pseudo-attribute
978 of the new entry's parents, and
980 privileges on the attributes that are present in the new relative DN.
982 privileges are also required on the attributes that are present
983 in the old relative DN if
994 pseudo-attribute of the searchBase
995 (NOTE: this was introduced with OpenLDAP 2.4).
996 Then, for each entry, it requires
998 privileges on the attributes that are defined in the filter.
999 The resulting entries are finally tested for
1001 privileges on the pseudo-attribute
1003 (for read access to the entry itself)
1006 access on each value of each attribute that is requested.
1009 object used in generating continuation references, the operation requires
1011 access on the pseudo-attribute
1013 (for read access to the referral object itself),
1016 access to the attribute holding the referral information
1022 Some internal operations and some
1024 require specific access privileges.
1031 privileges on all the attributes that are present in the search filter
1032 of the URI regexp maps (the right-hand side of the
1036 privileges are also required on the
1038 attribute of the authorizing identity and/or on the
1040 attribute of the authorized identity.
1041 In general, when an internal lookup is performed for authentication
1042 or authorization purposes, search-specific privileges (see the access
1043 requirements for the search operation illustrated above) are relaxed to
1047 Access control to search entries is checked by the frontend,
1048 so it is fully honored by all backends; for all other operations
1049 and for the discovery phase of the search operation,
1050 full ACL semantics is only supported by the primary backends, i.e.
1055 Some other backend, like
1057 may fully support them; others may only support a portion of the
1058 described semantics, or even differ in some aspects.
1059 The relevant details are described in the backend-specific man pages.
1062 It is strongly recommended to explicitly use the most appropriate
1068 clauses, to avoid possible incorrect specifications of the access rules
1069 as well as for performance (avoid unnecessary regex matching when an exact
1070 match suffices) reasons.
1072 An administrator might create a rule of the form:
1075 access to dn.regex="dc=example,dc=com"
1079 expecting it to match all entries in the subtree "dc=example,dc=com".
1080 However, this rule actually matches any DN which contains anywhere
1081 the substring "dc=example,dc=com". That is, the rule matches both
1082 "uid=joe,dc=example,dc=com" and "dc=example,dc=com,uid=joe".
1084 To match the desired subtree, the rule would be more precisely
1088 access to dn.regex="^(.+,)?dc=example,dc=com$"
1092 For performance reasons, it would be better to use the subtree style.
1095 access to dn.subtree="dc=example,dc=com"
1099 When writing submatch rules, it may be convenient to avoid unnecessary
1102 use; for instance, to allow access to the subtree of the user
1105 clause, one could use
1108 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1109 by dn.regex="^uid=$2,dc=example,dc=com$$" write
1113 However, since all that is required in the
1115 clause is substring expansion, a more efficient solution is
1118 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1119 by dn.exact,expand="uid=$2,dc=example,dc=com" write
1127 implies substring expansion,
1129 as well as all the other DN specific
1131 values, does not, so it must be explicitly requested.
1136 default slapd configuration file
1144 "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
1145 .SH ACKNOWLEDGEMENTS