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.
5 slapd.access \- access configuration for slapd, the stand-alone LDAP daemon
11 file contains configuration information for the
13 daemon. This configuration file is also used by the SLAPD tools
25 file consists of a series of global configuration options that apply to
27 as a whole (including all backends), followed by zero or more database
28 backend definitions that contain information specific to a backend
36 # comment - these options apply to every database
37 <global configuration options>
38 # first database definition & configuration options
39 database <backend 1 type>
40 <configuration options specific to backend 1>
41 # subsequent database definitions & configuration options
45 Both the global configuration and each backend-specific section can
46 contain access information. Backend-specific access control
47 directives are used for those entries that belong to the backend,
48 according to their naming context. In case no access control
49 directives are defined for a backend or those which are defined are
50 not applicable, the directives from the global configuration section
53 If no access controls are present, the default policy
54 allows anyone and everyone to read anything but restricts
55 updates to rootdn. (e.g., "access to * by * read").
56 The rootdn can always read and write EVERYTHING!
58 For entries not held in any backend (such as a root DSE), the
59 directives of the first backend (and any global directives) are
62 Arguments that should be replaced by actual text are shown in
64 .SH THE ACCESS DIRECTIVE
65 The structure of the access control directives is
67 .B access to <what> "[ by <who> [ <access> ] [ <control> ] ]+"
68 Grant access (specified by
70 to a set of entries and/or attributes (specified by
72 by one or more requestors (specified by
76 Lists of access directives are evaluated in the order they appear
80 clause matches the datum whose access is being evaluated, its
82 clause list is checked.
85 clause matches the accessor's properties, its
89 clauses are evaluated.
90 Access control checking stops at the first match of the
94 clause, unless otherwise dictated by the
99 clause list is implicitly terminated by a
105 clause that results in stopping the access control with no access
109 clause list is implicitly terminated by a
116 clause that results in granting no access privileges to an otherwise
121 specifies the entity the access control directive applies to.
122 It can have the forms
125 dn[.<dnstyle>]=<dnpattern>
127 attrs=<attrlist>[ val[/matchingRule][.<attrstyle>]=<attrval>]
133 <dnstyle>={{exact|base(object)}|regex
134 |one(level)|sub(tree)|children}
135 <attrlist>={<attr>|[{!|@}]<objectClass>}[,<attrlist>]
136 <attrstyle>={{exact|base(object)}|regex
137 |one(level)|sub(tree)|children}
142 selects the entries based on their naming context.
145 is a string representation of the entry's DN.
148 stands for all the entries, and it is implied if no
154 is optional; however, it is recommended to specify it to avoid ambiguities.
163 indicates the entry whose DN is equal to the
168 indicates all the entries immediately below the
173 indicates all entries in the subtree at the
176 indicates all the entries below (subordinate to) the
185 is a POSIX (''extended'') regular expression pattern,
190 matching a normalized string representation of the entry's DN.
191 The regex form of the pattern does not (yet) support UTF\-8.
194 .B filter=<ldapfilter>
195 selects the entries based on a valid LDAP filter as described in RFC 4515.
204 selects the attributes the access control rule applies to.
205 It is a comma-separated list of attribute types, plus the special names
207 indicating access to the entry itself, and
209 indicating access to the entry's children. ObjectClass names may also
210 be specified in this list, which will affect all the attributes that
211 are required and/or allowed by that objectClass.
216 are directly treated as objectClass names. A name prefixed by
218 is also treated as an objectClass, but in this case the access rule
219 affects the attributes that are not required nor allowed
224 .B attrs=@extensibleObject
225 is implied, i.e. all attributes are addressed.
228 .B attrs=<attr> val[/matchingRule][.<attrstyle>]=<attrval>
229 specifies access to a particular value of a single attribute.
230 In this case, only a single attribute type may be given. The
233 (the default) uses the attribute's equality matching rule to compare the
234 value, unless a different (and compatible) matching rule is specified. If the
238 the provided value is used as a POSIX (''extended'') regular
239 expression pattern. If the attribute has DN syntax, the
247 resulting in base, onelevel, subtree or children match, respectively.
249 The dn, filter, and attrs statements are additive; they can be used in sequence
250 to select entities the access rule applies to based on naming context,
251 value and attribute type simultaneously.
255 indicates whom the access rules apply to.
258 statements can appear in an access control statement, indicating the
259 different access privileges to the same resource that apply to different
261 It can have the forms
269 dn[.<dnstyle>[,<modifier>]]=<DN>
274 realself[.<selfstyle>]
276 realdn[.<dnstyle>[,<modifier>]]=<DN>
277 realdnattr=<attrname>
279 group[/<objectclass>[/<attrname>]]
280 [.<groupstyle>]=<group>
281 peername[.<peernamestyle>]=<peername>
282 sockname[.<style>]=<sockname>
283 domain[.<domainstyle>[,<modifier>]]=<domain>
284 sockurl[.<style>]=<sockurl>
285 set[.<setstyle>]=<pattern>
292 dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
298 <style>={exact|regex|expand}
299 <selfstyle>={level{<n>}}
300 <dnstyle>={{exact|base(object)}|regex
301 |one(level)|sub(tree)|children|level{<n>}}
302 <groupstyle>={exact|expand}
303 <peernamestyle>={<style>|ip|ipv6|path}
304 <domainstyle>={exact|regex|sub(tree)}
305 <setstyle>={exact|regex}
307 <name>=aci <pattern>=<attrname>]
310 They may be specified in combination.
319 The keywords prefixed by
321 act as their counterparts without prefix; the checking respectively occurs
322 with the \fIauthentication\fP DN and the \fIauthorization\fP DN.
326 means access is granted to unauthenticated clients; it is mostly used
327 to limit access to authentication resources (e.g. the
329 attribute) to unauthenticated clients for authentication purposes.
333 means access is granted to authenticated clients.
337 means access to an entry is allowed to the entry itself (e.g. the entry
338 being accessed and the requesting entry must be the same).
341 style, where \fI<n>\fP indicates what ancestor of the DN
342 is to be used in matches.
343 A positive value indicates that the <n>-th ancestor of the user's DN
344 is to be considered; a negative value indicates that the <n>-th ancestor
345 of the target is to be considered.
346 For example, a "\fIby self.level{1} ...\fP" clause would match
347 when the object "\fIdc=example,dc=com\fP" is accessed
348 by "\fIcn=User,dc=example,dc=com\fP".
349 A "\fIby self.level{-1} ...\fP" clause would match when the same user
350 accesses the object "\fIou=Address Book,cn=User,dc=example,dc=com\fP".
354 means that access is granted to the matching DN.
355 The optional style qualifier
357 allows the same choices of the dn form of the
359 field. In addition, the
361 style can exploit substring substitution of submatches in the
363 dn.regex clause by using the form
367 ranging from 0 to 9 (where 0 matches the entire string),
370 for submatches higher than 9.
371 Since the dollar character is used to indicate a substring replacement,
372 the dollar character that is used to indicate match up to the end of
373 the string must be escaped by a second dollar character, e.g.
376 access to dn.regex="^(.+,)?uid=([^,]+),dc=[^,]+,dc=com$"
377 by dn.regex="^uid=$2,dc=[^,]+,dc=com$$" write
383 At present, the only type allowed is
385 which causes substring substitution of submatches to take place
392 dnstyle in the above example may be of use only if the
394 clause needs to be a regex; otherwise, if the
395 value of the second (from the right)
397 portion of the DN in the above example were fixed, the form
400 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
401 by dn.exact,expand="uid=$2,dc=example,dc=com" write
404 could be used; if it had to match the value in the
409 access to dn.regex="^(.+,)?uid=([^,]+),dc=([^,]+),dc=com$"
410 by dn.exact,expand="uid=$2,dc=$3,dc=com" write
417 clause other than regex may provide submatches as well.
428 as the match of the entire string.
437 as the match of the rightmost part of the DN as defined in the
440 This may be useful, for instance, to provide access to all the
441 ancestors of a user by defining
444 access to dn.subtree="dc=com"
445 by dn.subtree,expand="$1" read
448 which means that only access to entries that appear in the DN of the
454 form is an extension and a generalization of the
456 form, which matches all DNs whose <n>-th ancestor is the pattern.
457 So, \fIlevel{1}\fP is equivalent to \fIonelevel\fP,
458 and \fIlevel{0}\fP is equivalent to \fIbase\fP.
460 It is perfectly useless to give any access privileges to a DN
461 that exactly matches the
463 of the database the ACLs apply to, because it implicitly
464 possesses write privileges for the entire tree of that database.
465 Actually, access control is bypassed for the
467 to solve the intrinsic chicken-and-egg problem.
471 means that access is granted to requests whose DN is listed in the
472 entry being accessed under the
478 means that access is granted to requests whose DN is listed
479 in the group entry whose DN is given by
481 The optional parameters
485 define the objectClass and the member attributeType of the group entry.
491 The optional style qualifier
497 will be expanded as a replacement string (but not as a regular expression)
504 which means that exact match will be used.
505 If the style of the DN portion of the
507 clause is regex, the submatches are made available according to
511 other styles provide limited submatches as discussed above about
516 For static groups, the specified attributeType must have
519 .B NameAndOptionalUID
520 syntax. For dynamic groups the attributeType must
523 attributeType. Only LDAP URIs of the form
524 .B ldap:///<base>??<scope>?<filter>
525 will be evaluated in a dynamic group, by searching the local server only.
528 .BR peername=<peername> ,
529 .BR sockname=<sockname> ,
530 .BR domain=<domain> ,
532 .BR sockurl=<sockurl>
533 mean that the contacting host IP (in the form
536 .BR "IP=[<ipv6>]:<port>"
538 or the contacting host named pipe file name (in the form
540 if connecting through a named pipe) for
542 the named pipe file name for
544 the contacting host name for
546 and the contacting URL for
553 rules for pattern match described for the
557 style, which implies submatch
559 and regex match of the corresponding connection parameters.
564 clause (the default) implies a case-exact match on the client's
568 prefix and the trailing
574 prefix if connecting through a named pipe.
577 style interprets the pattern as
578 .BR <peername>=<ip>[%<mask>][{<n>}] ,
583 are dotted digit representations of the IP and the mask, while
585 delimited by curly brackets, is an optional port.
586 The same applies to IPv6 addresses when the special
589 When checking access privileges, the IP portion of the
591 is extracted, eliminating the
595 part, and it is compared against the
597 portion of the pattern after masking with
599 \fI((peername & <mask>) == <ip>)\fP.
601 .B peername.ip=127.0.0.1
604 allow connections only from localhost,
605 .B peername.ip=192.168.1.0%255.255.255.0
606 allows connections from any IP in the 192.168.1 class C domain, and
607 .B peername.ip=192.168.1.16%255.255.255.240{9009}
608 allows connections from any IP in the 192.168.1.[16-31] range
609 of the same domain, only if port 9009 is used.
616 when connecting through a named pipe, and performs an exact match
617 on the given pattern.
620 clause also allows the
622 style, which succeeds when a fully qualified name exactly matches the
624 pattern, or its trailing part, after a
631 style is allowed, implying an
633 match with submatch expansion; the use of
635 as a style modifier is considered more appropriate.
637 .B domain.subtree=example.com
638 will match www.example.com, but will not match www.anotherexample.com.
641 of the contacting host is determined by performing a DNS reverse lookup.
642 As this lookup can easily be spoofed, use of the
644 statement is strongly discouraged. By default, reverse lookups are disabled.
651 option; the only value currently supported is
653 which causes substring substitution of submatches to take place even if
658 much like the analogous usage in
667 .B dynacl/<name>[/<options>][.<dynstyle>][=<pattern>]
668 means that access checking is delegated to the admin-defined method
671 which can be registered at run-time by means of the
679 are optional, and are directly passed to the registered parsing routine.
680 Dynacl is experimental; it must be enabled at compile time.
683 .B dynacl/aci[=<attrname>]
684 means that the access control is determined by the values in the
689 indicates what attributeType holds the ACI information in the entry.
692 operational attribute is used.
693 ACIs are experimental; they must be enabled at compile time.
697 .BR transport_ssf=<n> ,
701 set the minimum required Security Strength Factor (ssf) needed
702 to grant access. The value should be positive integer.
703 .SH THE <ACCESS> FIELD
705 .B <access> ::= [[real]self]{<level>|<priv>}
706 determines the access level or the specific access privileges the
709 Its component are defined as
712 <level> ::= none|disclose|auth|compare|search|read|write|manage
713 <priv> ::= {=|+|-}{m|w|r|s|c|x|d|0}+
718 allows special operations like having a certain access level or privilege
719 only in case the operation involves the name of the user that's requesting
721 It implies the user that requests access is authorized.
724 refers to the authenticated DN as opposed to the authorized DN of the
729 access to the member attribute of a group, which allows one to add/delete
730 its own DN from the member list of a group, without affecting other members.
734 access model relies on an incremental interpretation of the access
736 The possible levels are
745 Each access level implies all the preceding ones, thus
747 grants all access including administrative access,
751 access level disallows all access including disclosure on error.
755 access level allows disclosure of information on error.
759 access level means that one is allowed access to an attribute to perform
760 authentication/authorization operations (e.g.
762 with no other access.
763 This is useful to grant unauthenticated clients the least possible
764 access level to critical resources, like passwords.
768 access model relies on the explicit setting of access privileges
772 sign resets previously defined accesses; as a consequence, the final
773 access privileges will be only those defined by the clause.
778 signs add/remove access privileges to the existing ones.
791 for authentication, and
794 More than one of the above privileges can be added in one statement.
796 indicates no privileges and is used only by itself (e.g., +0).
798 If no access is given, it defaults to
800 .SH THE <CONTROL> FIELD
803 controls the flow of access rule application.
804 It can have the forms
814 the default, means access checking stops in case of match.
815 The other two forms are used to keep on processing access clauses.
818 form allows for other
822 clause to be considered, so that they may result in incrementally altering
823 the privileges, while the
825 form allows for other
827 clauses that match the same target to be processed.
828 Consider the (silly) example
831 access to dn.subtree="dc=example,dc=com" attrs=cn
834 access to dn.subtree="ou=People,dc=example,dc=com"
838 which allows search and compare privileges to everybody under
839 the "dc=example,dc=com" tree, with the second rule allowing
840 also read in the "ou=People" subtree,
841 or the (even more silly) example
844 access to dn.subtree="dc=example,dc=com" attrs=cn
849 which grants everybody search and compare privileges, and adds read
850 privileges to authenticated clients.
852 One useful application is to easily grant write privileges to an
854 that is different from the
856 In this case, since the
858 needs write access to (almost) all data, one can use
862 by dn.exact="cn=The Update DN,dc=example,dc=com" write
866 as the first access rule.
867 As a consequence, unless the operation is performed with the
869 identity, control is passed straight to the subsequent rules.
871 .SH OPERATION REQUIREMENTS
872 Operations require different privileges on different portions of entries.
873 The following summary applies to primary database backends such as
874 the BDB and HDB backends. Requirements for other backends may
875 (and often do) differ.
882 privileges on the pseudo-attribute
884 of the entry being added, and
886 privileges on the pseudo-attribute
888 of the entry's parent.
889 When adding the suffix entry of a database, write access to
891 of the empty DN ("") is required.
896 operation, when credentials are stored in the directory, requires
898 privileges on the attribute the credentials are stored in (usually
906 privileges on the attribute that is being compared.
913 privileges on the pseudo-attribute
915 of the entry being deleted, and
919 pseudo-attribute of the entry's parent.
926 privileges on the attributes being modified.
933 privileges on the pseudo-attribute
935 of the entry whose relative DN is being modified,
937 privileges on the pseudo-attribute
939 of the old and new entry's parents, and
941 privileges on the attributes that are present in the new relative DN.
943 privileges are also required on the attributes that are present
944 in the old relative DN if
955 pseudo-attribute of the searchBase
956 (NOTE: this was introduced with OpenLDAP 2.4).
957 Then, for each entry, it requires
959 privileges on the attributes that are defined in the filter.
960 The resulting entries are finally tested for
962 privileges on the pseudo-attribute
964 (for read access to the entry itself)
967 access on each value of each attribute that is requested.
970 object used in generating continuation references, the operation requires
972 access on the pseudo-attribute
974 (for read access to the referral object itself),
977 access to the attribute holding the referral information
983 Some internal operations and some
985 require specific access privileges.
992 privileges on all the attributes that are present in the search filter
993 of the URI regexp maps (the right-hand side of the
997 privileges are also required on the
999 attribute of the authorizing identity and/or on the
1001 attribute of the authorized identity.
1002 In general, when an internal lookup is performed for authentication
1003 or authorization purposes, search-specific privileges (see the access
1004 requirements for the search operation illustrated above) are relaxed to
1008 Access control to search entries is checked by the frontend,
1009 so it is fully honored by all backends; for all other operations
1010 and for the discovery phase of the search operation,
1011 full ACL semantics is only supported by the primary backends, i.e.
1016 Some other backend, like
1018 may fully support them; others may only support a portion of the
1019 described semantics, or even differ in some aspects.
1020 The relevant details are described in the backend-specific man pages.
1023 It is strongly recommended to explicitly use the most appropriate
1029 clauses, to avoid possible incorrect specifications of the access rules
1030 as well as for performance (avoid unnecessary regex matching when an exact
1031 match suffices) reasons.
1033 An administrator might create a rule of the form:
1036 access to dn.regex="dc=example,dc=com"
1040 expecting it to match all entries in the subtree "dc=example,dc=com".
1041 However, this rule actually matches any DN which contains anywhere
1042 the substring "dc=example,dc=com". That is, the rule matches both
1043 "uid=joe,dc=example,dc=com" and "dc=example,dc=com,uid=joe".
1045 To match the desired subtree, the rule would be more precisely
1049 access to dn.regex="^(.+,)?dc=example,dc=com$"
1053 For performance reasons, it would be better to use the subtree style.
1056 access to dn.subtree="dc=example,dc=com"
1060 When writing submatch rules, it may be convenient to avoid unnecessary
1063 use; for instance, to allow access to the subtree of the user
1066 clause, one could use
1069 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1070 by dn.regex="^uid=$2,dc=example,dc=com$$" write
1074 However, since all that is required in the
1076 clause is substring expansion, a more efficient solution is
1079 access to dn.regex="^(.+,)?uid=([^,]+),dc=example,dc=com$"
1080 by dn.exact,expand="uid=$2,dc=example,dc=com" write
1088 implies substring expansion,
1090 as well as all the other DN specific
1092 values, does not, so it must be explicitly requested.
1097 default slapd configuration file
1105 "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
1106 .SH ACKNOWLEDGEMENTS