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7 Network Working Group S. Legg
8 Request for Comments: 3687 Adacel Technologies
9 Category: Standards Track February 2004
12 Lightweight Directory Access Protocol (LDAP)
13 and X.500 Component Matching Rules
15 Status of this Memo
17 This document specifies an Internet standards track protocol for the
18 Internet community, and requests discussion and suggestions for
19 improvements. Please refer to the current edition of the "Internet
20 Official Protocol Standards" (STD 1) for the standardization state
21 and status of this protocol. Distribution of this memo is unlimited.
23 Copyright Notice
25 Copyright (C) The Internet Society (2004). All Rights Reserved.
27 Abstract
29 The syntaxes of attributes in a Lightweight Directory Access Protocol
30 (LDAP) or X.500 directory range from simple data types, such as text
31 string, integer, or boolean, to complex structured data types, such
32 as the syntaxes of the directory schema operational attributes.
33 Matching rules defined for the complex syntaxes usually only provide
34 the most immediately useful matching capability. This document
35 defines generic matching rules that can match any user selected
36 component parts in an attribute value of any arbitrarily complex
37 attribute syntax.
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60 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
63 Table of Contents
65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
66 2. Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . 4
67 3. ComponentAssertion . . . . . . . . . . . . . . . . . . . . . . 5
68 3.1. Component Reference. . . . . . . . . . . . . . . . . . . 6
69 3.1.1. Component Type Substitutions . . . . . . . . . . 7
70 3.1.2. Referencing SET, SEQUENCE and CHOICE Components. 8
71 3.1.3. Referencing SET OF and SEQUENCE OF Components. . 9
72 3.1.4. Referencing Components of Parameterized Types. . 10
73 3.1.5. Component Referencing Example. . . . . . . . . . 10
74 3.1.6. Referencing Components of Open Types . . . . . . 12
75 3.1.6.1. Open Type Referencing Example . . . . . 12
76 3.1.7. Referencing Contained Types. . . . . . . . . . . 14
77 3.1.7.1. Contained Type Referencing Example. . . 14
78 3.2. Matching of Components . . . . . . . . . . . . . . . . . 15
79 3.2.1. Applicability of Existing Matching Rules . . . . 17
80 3.2.1.1. String Matching . . . . . . . . . . . . 17
81 3.2.1.2. Telephone Number Matching . . . . . . . 17
82 3.2.1.3. Distinguished Name Matching . . . . . . 18
83 3.2.2. Additional Useful Matching Rules . . . . . . . . 18
84 3.2.2.1. The rdnMatch Matching Rule. . . . . . . 18
85 3.2.2.2. The presentMatch Matching Rule. . . . . 19
86 3.2.3. Summary of Useful Matching Rules . . . . . . . . 20
87 4. ComponentFilter. . . . . . . . . . . . . . . . . . . . . . . . 21
88 5. The componentFilterMatch Matching Rule . . . . . . . . . . . . 22
89 6. Equality Matching of Complex Components. . . . . . . . . . . . 24
90 6.1. The OpenAssertionType Syntax . . . . . . . . . . . . . . 24
91 6.2. The allComponentsMatch Matching Rule . . . . . . . . . . 25
92 6.3. Deriving Component Equality Matching Rules . . . . . . . 27
93 6.4. The directoryComponentsMatch Matching Rule . . . . . . . 28
94 7. Component Matching Examples. . . . . . . . . . . . . . . . . . 30
95 8. Security Considerations. . . . . . . . . . . . . . . . . . . . 37
96 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 37
97 10. IANA Considerations. . . . . . . . . . . . . . . . . . . . . . 37
98 11. References . . . . . . . . . . . . . . . . . . . . . . . . . . 38
99 11.1. Normative References. . . . . . . . . . . . . . . . . . 38
100 11.2. Informative References. . . . . . . . . . . . . . . . . 40
101 12. Intellectual Property Statement. . . . . . . . . . . . . . . . 40
102 13. Author's Address . . . . . . . . . . . . . . . . . . . . . . . 41
103 14. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 42
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119 1. Introduction
121 The structure or data type of data held in an attribute of a
122 Lightweight Directory Access Protocol (LDAP) [7] or X.500 [19]
123 directory is described by the attribute's syntax. Attribute syntaxes
124 range from simple data types, such as text string, integer, or
125 boolean, to complex data types, for example, the syntaxes of the
126 directory schema operational attributes.
128 In X.500, the attribute syntaxes are explicitly described by Abstract
129 Syntax Notation One (ASN.1) [13] type definitions. ASN.1 type
130 notation has a number of simple data types (e.g., PrintableString,
131 INTEGER, BOOLEAN), and combining types (i.e., SET, SEQUENCE, SET OF,
132 SEQUENCE OF, and CHOICE) for constructing arbitrarily complex data
133 types from simpler component types. In LDAP, the attribute syntaxes
134 are usually described in Augmented Backus-Naur Form (ABNF) [2],
135 though there is an implied association between the LDAP attribute
136 syntaxes and the X.500 ASN.1 types. To a large extent, the data
137 types of attribute values in either an LDAP or X.500 directory are
138 described by ASN.1 types. This formal description can be exploited
139 to identify component parts of an attribute value for a variety of
140 purposes. This document addresses attribute value matching.
142 With any complex attribute syntax there is normally a requirement to
143 partially match an attribute value of that syntax by matching only
144 selected components of the value. Typically, matching rules specific
145 to the attribute syntax are defined to fill this need. These highly
146 specific matching rules usually only provide the most immediately
147 useful matching capability. Some complex attribute syntaxes don't
148 even have an equality matching rule let alone any additional matching
149 rules for partial matching. This document defines a generic way of
150 matching user selected components in an attribute value of any
151 arbitrarily complex attribute syntax, where that syntax is described
152 using ASN.1 type notation. All of the type notations defined in
153 X.680 [13] are supported.
155 Section 3 describes the ComponentAssertion, a testable assertion
156 about the value of a component of an attribute value of any complex
157 syntax.
159 Section 4 introduces the ComponentFilter assertion, which is an
160 expression of ComponentAssertions. The ComponentFilter enables more
161 powerful filter matching of components in an attribute value.
163 Section 5 defines the componentFilterMatch matching rule, which
164 enables a ComponentFilter to be evaluated against attribute values.
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175 Section 6 defines matching rules for component-wise equality matching
176 of attribute values of any syntax described by an ASN.1 type
177 definition.
179 Examples showing the usage of componentFilterMatch are in Section 7.
181 For a new attribute syntax, the Generic String Encoding Rules [9] and
182 the specifications in sections 3 to 6 of this document make it
183 possible to fully and precisely define the LDAP-specific encoding,
184 the LDAP and X.500 binary encoding (and possibly other ASN.1
185 encodings in the future), a suitable equality matching rule, and a
186 comprehensive collection of component matching capabilities, by
187 simply writing down an ASN.1 type definition for the syntax. These
188 implicit definitions are also automatically extended if the ASN.1
189 type is later extended. The algorithmic relationship between the
190 ASN.1 type definition, the various encodings and the component
191 matching behaviour makes directory server implementation support for
192 the component matching rules amenable to automatic code generation
193 from ASN.1 type definitions.
195 Schema designers have the choice of storing related items of data as
196 a single attribute value of a complex syntax in some entry, or as a
197 subordinate entry where the related data items are stored as separate
198 attribute values of simpler syntaxes. The inability to search
199 component parts of a complex syntax has been used as an argument for
200 favouring the subordinate entries approach. The component matching
201 rules provide the analogous matching capability on an attribute value
202 of a complex syntax that a search filter has on a subordinate entry.
204 Most LDAP syntaxes have corresponding ASN.1 type definitions, though
205 they are usually not reproduced or referenced alongside the formal
206 definition of the LDAP syntax. Syntaxes defined with only a
207 character string encoding, i.e., without an explicit or implied
208 corresponding ASN.1 type definition, cannot use the component
209 matching capabilities described in this document unless and until a
210 semantically equivalent ASN.1 type definition is defined for them.
212 2. Conventions
214 Throughout this document "type" shall be taken to mean an ASN.1 type
215 unless explicitly qualified as an attribute type, and "value" shall
216 be taken to mean an ASN.1 value unless explicitly qualified as an
217 attribute value.
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231 Note that "ASN.1 value" does not mean a Basic Encoding Rules (BER)
232 [17] encoded value. The ASN.1 value is an abstract concept that is
233 independent of any particular encoding. BER is just one possible
234 encoding of an ASN.1 value. The component matching rules operate at
235 the abstract level without regard for the possible encodings of a
236 value.
238 Attribute type and matching rule definitions in this document are
239 provided in both the X.500 [10] and LDAP [4] description formats.
240 Note that the LDAP descriptions have been rendered with additional
241 white-space and line breaks for the sake of readability.
243 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
244 "SHOULD", "SHOULD NOT", "RECOMMENDED" and "MAY" in this document are
245 to be interpreted as described in BCP 14, RFC 2119 [1]. The key word
246 "OPTIONAL" is exclusively used with its ASN.1 meaning.
248 3. ComponentAssertion
250 A ComponentAssertion is an assertion about the presence, or values
251 of, components within an ASN.1 value, i.e., an instance of an ASN.1
252 type. The ASN.1 value is typically an attribute value, where the
253 ASN.1 type is the syntax of the attribute. However, a
254 ComponentAssertion may also be applied to a component part of an
255 attribute value. The assertion evaluates to either TRUE, FALSE or
256 Undefined for each tested ASN.1 value.
258 A ComponentAssertion is described by the following ASN.1 type
259 (assumed to be defined with "EXPLICIT TAGS" in force):
261 ComponentAssertion ::= SEQUENCE {
262 component ComponentReference (SIZE(1..MAX)) OPTIONAL,
263 useDefaultValues BOOLEAN DEFAULT TRUE,
264 rule MATCHING-RULE.&id,
265 value MATCHING-RULE.&AssertionType }
267 ComponentReference ::= UTF8String
269 MATCHING-RULE.&id equates to the OBJECT IDENTIFIER of a matching
270 rule. MATCHING-RULE.&AssertionType is an open type (formerly known
271 as the ANY type).
273 The "component" field of a ComponentAssertion identifies which
274 component part of a value of some ASN.1 type is to be tested, the
275 "useDefaultValues" field indicates whether DEFAULT values are to be
276 substituted for absent component values, the "rule" field indicates
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287 how the component is to be tested, and the "value" field is an
288 asserted ASN.1 value against which the component is tested. The
289 ASN.1 type of the asserted value is determined by the chosen rule.
291 The fields of a ComponentAssertion are described in detail in the
292 following sections.
294 3.1. Component Reference
296 The component field in a ComponentAssertion is a UTF-8 character
297 string [6] whose textual content is a component reference,
298 identifying a component part of some ASN.1 type or value. A
299 component reference conforms to the following ABNF [2], which extends
300 the notation defined in Clause 14 of X.680 [13]:
302 component-reference = ComponentId *( "." ComponentId )
303 ComponentId = identifier /
304 from-beginning /
305 count /
306 from-end / ; extends Clause 14
307 content / ; extends Clause 14
308 select / ; extends Clause 14
309 all
311 identifier = lowercase *alphanumeric
312 *(hyphen 1*alphanumeric)
313 alphanumeric = uppercase / lowercase / decimal-digit
314 uppercase = %x41-5A ; "A" to "Z"
315 lowercase = %x61-7A ; "a" to "z"
316 hyphen = "-"
318 from-beginning = positive-number
319 count = "0"
320 from-end = "-" positive-number
321 content = %x63.6F.6E.74.65.6E.74 ; "content"
322 select = "(" Value *( "," Value ) ")"
323 all = "*"
326 positive-number = non-zero-digit *decimal-digit
328 decimal-digit = %x30-39 ; "0" to "9"
329 non-zero-digit = %x31-39 ; "1" to "9"
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343 An <identifier> conforms to the definition of an identifier in ASN.1
344 notation (Clause 11.3 of X.680 [13]). It begins with a lowercase
345 letter and is followed by zero or more letters, digits, and hyphens.
346 A hyphen is not permitted to be the last character and a hyphen is
347 not permitted to be followed by another hyphen.
349 The <Value> rule is described by the Generic String Encoding Rules
350 (GSER) [9].
352 A component reference is a sequence of one or more ComponentIds where
353 each successive ComponentId identifies either an inner component at
354 the next level of nesting of an ASN.1 combining type, i.e., SET,
355 SEQUENCE, SET OF, SEQUENCE OF, or CHOICE, or a specific type within
356 an ASN.1 open type.
358 A component reference is always considered in the context of a
359 particular complex ASN.1 type. When applied to the ASN.1 type the
360 component reference identifies a specific component type. When
361 applied to a value of the ASN.1 type a component reference identifies
362 zero, one or more component values of that component type. The
363 component values are potentially in a DEFAULT value if
364 useDefaultValues is TRUE. The specific component type identified by
365 the component reference determines what matching rules are capable of
366 being used to match the component values.
368 The component field in a ComponentAssertion may also be absent, in
369 which case the identified component type is the ASN.1 type to which
370 the ComponentAssertion is applied, and the identified component value
371 is the whole ASN.1 value.
373 A valid component reference for a particular complex ASN.1 type is
374 constructed by starting with the outermost combining type and
375 repeatedly selecting one of the permissible forms of ComponentId to
376 identify successively deeper nested components. A component
377 reference MAY identify a component with a complex ASN.1 type, i.e.,
378 it is not required that the component type identified by a component
379 reference be a simple ASN.1 type.
381 3.1.1. Component Type Substitutions
383 ASN.1 type notation has a number of constructs for referencing other
384 defined types, and constructs that are irrelevant for matching
385 purposes. These constructs are not represented in a component
386 reference in any way and substitutions of the component type are
387 performed to eliminate them from further consideration. These
388 substitutions automatically occur prior to each ComponentId, whether
389 constructing or interpreting a component reference, but do not occur
390 after the last ComponentId, except as allowed by Section 3.2.
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399 If the ASN.1 type is an ASN.1 type reference then the component type
400 is taken to be the actual definition on the right hand side of the
401 type assignment for the referenced type.
403 If the ASN.1 type is a tagged type then the component type is taken
404 to be the type without the tag.
406 If the ASN.1 type is a constrained type (see X.680 [13] and X.682
407 [15] for the details of ASN.1 constraint notation) then the component
408 type is taken to be the type without the constraint.
410 If the ASN.1 type is an ObjectClassFieldType (Clause 14 of X.681
411 [14]) that denotes a specific ASN.1 type (e.g., MATCHING-RULE.&id
412 denotes the OBJECT IDENTIFIER type) then the component type is taken
413 to be the denoted type. Section 3.1.6 describes the case where the
414 ObjectClassFieldType denotes an open type.
416 If the ASN.1 type is a selection type other than one used in the list
417 of components for a SET or SEQUENCE type then the component type is
418 taken to be the selected alternative type from the named CHOICE.
420 If the ASN.1 type is a TypeFromObject (Clause 15 of X.681 [14]) then
421 the component type is taken to be the denoted type.
423 If the ASN.1 type is a ValueSetFromObjects (Clause 15 of X.681 [14])
424 then the component type is taken to be the governing type of the
425 denoted values.
427 3.1.2. Referencing SET, SEQUENCE and CHOICE Components
429 If the ASN.1 type is a SET or SEQUENCE type then the <identifier>
430 form of ComponentId may be used to identify the component type within
431 that SET or SEQUENCE having that identifier. If <identifier>
432 references an OPTIONAL component type and that component is not
433 present in a particular value then there are no corresponding
434 component values. If <identifier> references a DEFAULT component
435 type and useDefaultValues is TRUE (the default setting for
436 useDefaultValues) and that component is not present in a particular
437 value then the component value is taken to be the default value. If
438 <identifier> references a DEFAULT component type and useDefaultValues
439 is FALSE and that component is not present in a particular value then
440 there are no corresponding component values.
442 If the ASN.1 type is a CHOICE type then the <identifier> form of
443 ComponentId may be used to identify the alternative type within that
444 CHOICE having that identifier. If <identifier> references an
445 alternative other than the one used in a particular value then there
446 are no corresponding component values.
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452 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
455 The COMPONENTS OF notation in Clause 24 of X.680 [13] augments the
456 defined list of components in a SET or SEQUENCE type by including all
457 the components of another defined SET or SEQUENCE type respectively.
458 These included components are referenced directly by identifier as
459 though they were defined in-line in the SET or SEQUENCE type
460 containing the COMPONENTS OF notation.
462 The SelectionType (Clause 29 of X.680 [13]), when used in the list of
463 components for a SET or SEQUENCE type, includes a single component
464 from a defined CHOICE type. This included component is referenced
465 directly by identifier as though it was defined in-line in the SET or
466 SEQUENCE type.
468 The REAL type is treated as though it is the SEQUENCE type defined in
469 Clause 20.5 of X.680 [13].
471 The EMBEDDED PDV type is treated as though it is the SEQUENCE type
472 defined in Clause 33.5 of X.680 [13].
474 The EXTERNAL type is treated as though it is the SEQUENCE type
475 defined in Clause 8.18.1 of X.690 [17].
477 The unrestricted CHARACTER STRING type is treated as though it is the
478 SEQUENCE type defined in Clause 40.5 of X.680 [13].
480 The INSTANCE OF type is treated as though it is the SEQUENCE type
481 defined in Annex C of X.681 [14].
483 The <identifier> form MUST NOT be used on any other ASN.1 type.
485 3.1.3. Referencing SET OF and SEQUENCE OF Components
487 If the ASN.1 type is a SET OF or SEQUENCE OF type then the
488 <from-beginning>, <from-end>, <count> and <all> forms of ComponentId
489 may be used.
491 The <from-beginning> form of ComponentId may be used to identify one
492 instance (i.e., value) of the component type of the SET OF or
493 SEQUENCE OF type (e.g., if Foo ::= SET OF Bar, then Bar is the
494 component type), where the instances are numbered from one upwards.
495 If <from-beginning> references a higher numbered instance than the
496 last instance in a particular value of the SET OF or SEQUENCE OF type
497 then there is no corresponding component value.
499 The <from-end> form of ComponentId may be used to identify one
500 instance of the component type of the SET OF or SEQUENCE OF type,
501 where "-1" is the last instance, "-2" is the second last instance,
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511 and so on. If <from-end> references a lower numbered instance than
512 the first instance in a particular value of the SET OF or SEQUENCE OF
513 type then there is no corresponding component value.
515 The <count> form of ComponentId identifies a notional count of the
516 number of instances of the component type in a value of the SET OF or
517 SEQUENCE OF type. This count is not explicitly represented but for
518 matching purposes it has an assumed ASN.1 type of INTEGER (0..MAX).
519 A ComponentId of the <count> form, if used, MUST be the last
520 ComponentId in a component reference.
522 The <all> form of ComponentId may be used to simultaneously identify
523 all instances of the component type of the SET OF or SEQUENCE OF
524 type. It is through the <all> form that a component reference can
525 identify more than one component value. However, if a particular
526 value of the SET OF or SEQUENCE OF type is an empty list, then there
527 are no corresponding component values.
529 Where multiple component values are identified, the remaining
530 ComponentIds in the component reference, if any, can identify zero,
531 one or more subcomponent values for each of the higher level
532 component values.
534 The corresponding ASN.1 type for the <from-beginning>, <from-end>,
535 and <all> forms of ComponentId is the component type of the SET OF or
536 SEQUENCE OF type.
538 The <from-beginning>, <count>, <from-end> and <all> forms MUST NOT be
539 used on ASN.1 types other than SET OF or SEQUENCE OF.
541 3.1.4. Referencing Components of Parameterized Types
543 A component reference cannot be formed for a parameterized type
544 unless the type has been used with actual parameters, in which case
545 the type is treated as though the DummyReferences [16] have been
546 substituted with the actual parameters.
548 3.1.5. Component Referencing Example
550 Consider the following ASN.1 type definitions.
552 ExampleType ::= SEQUENCE {
553 part1 [0] INTEGER,
554 part2 [1] ExampleSet,
555 part3 [2] SET OF OBJECT IDENTIFIER,
556 part4 [3] ExampleChoice }
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567 ExampleSet ::= SET {
568 option PrintableString,
569 setting BOOLEAN }
571 ExampleChoice ::= CHOICE {
572 eeny-meeny BIT STRING,
573 miney-mo OCTET STRING }
575 Following are component references constructed with respect to the
576 type ExampleType.
578 The component reference "part1" identifies a component of a value of
579 ExampleType having the ASN.1 tagged type [0] INTEGER.
581 The component reference "part2" identifies a component of a value of
582 ExampleType having the ASN.1 type of [1] ExampleSet
584 The component reference "part2.option" identifies a component of a
585 value of ExampleType having the ASN.1 type of PrintableString. A
586 ComponentAssertion could also be applied to a value of ASN.1 type
587 ExampleSet, in which case the component reference "option" would
588 identify the same kind of information.
590 The component reference "part3" identifies a component of a value of
591 ExampleType having the ASN.1 type of [2] SET OF OBJECT IDENTIFIER.
593 The component reference "part3.2" identifies the second instance of
594 the part3 SET OF. The instance has the ASN.1 type of OBJECT
595 IDENTIFIER.
597 The component reference "part3.0" identifies the count of the number
598 of instances in the part3 SET OF. The count has the corresponding
599 ASN.1 type of INTEGER (0..MAX).
601 The component reference "part3.*" identifies all the instances in the
602 part3 SET OF. Each instance has the ASN.1 type of OBJECT IDENTIFIER.
604 The component reference "part4" identifies a component of a value of
605 ExampleType having the ASN.1 type of [3] ExampleChoice.
607 The component reference "part4.miney-mo" identifies a component of a
608 value of ExampleType having the ASN.1 type of OCTET STRING.
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623 3.1.6. Referencing Components of Open Types
625 If a sequence of ComponentIds identifies an ObjectClassFieldType
626 denoting an open type (e.g., ATTRIBUTE.&Type denotes an open type)
627 then the ASN.1 type of the component varies. An open type is
628 typically constrained by some other component(s) in an outer
629 enclosing type, either formally through the use of a component
630 relation constraint [15], or informally in the accompanying text, so
631 the actual ASN.1 type of a value of the open type will generally be
632 known. The constraint will also limit the range of permissible
633 types. The <select> form of ComponentId may be used to identify one
634 of these permissible types in an open type. Subcomponents of that
635 type can then be identified with further ComponentIds.
637 The other components constraining the open type are termed the
638 referenced components [15]. The <select> form contains a list of one
639 or more values which take the place of the value(s) of the referenced
640 component(s) to uniquely identify one of the permissible types of the
641 open type.
643 Where the open type is constrained by a component relation
644 constraint, there is a <Value> in the <select> form for each of the
645 referenced components in the component relation constraint, appearing
646 in the same order. The ASN.1 type of each of these values is the
647 same as the ASN.1 type of the corresponding referenced component.
648 The type of a referenced component is potentially any ASN.1 type
649 however it is typically an OBJECT IDENTIFIER or INTEGER, which means
650 that the <Value> in the <select> form of ComponentId will nearly
651 always be an <ObjectIdentifierValue> or <IntegerValue> [9].
652 Furthermore, component relation constraints typically have only one
653 referenced component.
655 Where the open type is not constrained by a component relation
656 constraint, the specification introducing the syntax containing the
657 open type should explicitly nominate the referenced components and
658 their order, so that the <select> form can be used.
660 If an instance of <select> contains a value other than the value of
661 the referenced component used in a particular value of the outer
662 enclosing type then there are no corresponding component values for
663 the open type.
665 3.1.6.1. Open Type Referencing Example
667 The ASN.1 type AttributeTypeAndValue [10] describes a single
668 attribute value of a nominated attribute type.
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679 AttributeTypeAndValue ::= SEQUENCE {
680 type ATTRIBUTE.&id ({SupportedAttributes}),
681 value ATTRIBUTE.&Type ({SupportedAttributes}{@type}) }
683 ATTRIBUTE.&id denotes an OBJECT IDENTIFIER and
684 ({SupportedAttributes}) constrains the OBJECT IDENTIFIER to be a
685 supported attribute type.
687 ATTRIBUTE.&Type denotes an open type, in this case an attribute
688 value, and ({SupportedAttributes}{@type}) is a component relation
689 constraint that constrains the open type to be of the attribute
690 syntax for the attribute type. The component relation constraint
691 references only the "type" component, which has the ASN.1 type of
692 OBJECT IDENTIFIER, thus if the <select> form of ComponentId is used
693 to identify attribute values of specific attribute types it will
694 contain a single OBJECT IDENTIFIER value.
696 The component reference "value" on AttributeTypeAndValue refers to
697 the open type.
699 One of the X.500 standard attributes is facsimileTelephoneNumber
700 [12], which is identified with the OBJECT IDENTIFIER 2.5.4.23, and is
701 defined to have the following syntax.
703 FacsimileTelephoneNumber ::= SEQUENCE {
704 telephoneNumber PrintableString(SIZE(1..ub-telephone-number)),
705 parameters G3FacsimileNonBasicParameters OPTIONAL }
707 The component reference "value.(2.5.4.23)" on AttributeTypeAndValue
708 specifies an attribute value with the FacsimileTelephoneNumber
709 syntax.
711 The component reference "value.(2.5.4.23).telephoneNumber" on
712 AttributeTypeAndValue identifies the telephoneNumber component of a
713 facsimileTelephoneNumber attribute value. The component reference
714 "value.(facsimileTelephoneNumber)" is equivalent to
715 "value.(2.5.4.23)".
717 If the AttributeTypeAndValue ASN.1 value contains an attribute type
718 other than facsimileTelephoneNumber then there are no corresponding
719 component values for the component references "value.(2.5.4.23)" and
720 "value.(2.5.4.23).telephoneNumber".
730 Legg Standards Track [Page 13]
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732 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
735 3.1.7. Referencing Contained Types
737 Sometimes the contents of a BIT STRING or OCTET STRING value are
738 required to be the encodings of other ASN.1 values of specific ASN.1
739 types. For example, the extnValue component of the Extension type
740 component in the Certificate type [11] is an OCTET STRING that is
741 required to contain a Distinguished Encoding Rules (DER) [17]
742 encoding of a certificate extension value. It is useful to be able
743 to refer to the embedded encoded value and its components. An
744 embedded encoded value is here referred to as a contained value and
745 its associated type as the contained type.
747 If the ASN.1 type is a BIT STRING or OCTET STRING type containing
748 encodings of other ASN.1 values then the <content> form of
749 ComponentId may be used to identify the contained type.
750 Subcomponents of that type can then be identified with further
751 ComponentIds.
753 The contained type may be (effectively) an open type, constrained by
754 some other component in an outer enclosing type (e.g., in a
755 certificate Extension, extnValue is constrained by the chosen
756 extnId). In these cases the next ComponentId, if any, MUST be of the
757 <select> form.
759 For the purpose of building component references, the content of the
760 extnValue OCTET STRING in the Extension type is assumed to be an open
761 type having a notional component relation constraint with the extnId
762 component as the single referenced component, i.e.,
764 EXTENSION.&ExtnType ({ExtensionSet}{@extnId})
766 The data-value component of the associated types for the EMBEDDED PDV
767 and CHARACTER STRING types is an OCTET STRING containing the encoding
768 of a data value described by the identification component. For the
769 purpose of building component references, the content of the
770 data-value OCTET STRING in these types is assumed to be an open type
771 having a notional component relation constraint with the
772 identification component as the single referenced component.
774 3.1.7.1. Contained Type Referencing Example
776 The Extension ASN.1 type [11] describes a single certificate
777 extension value of a nominated extension type.
786 Legg Standards Track [Page 14]
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788 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
791 Extension ::= SEQUENCE {
792 extnId EXTENSION.&id ({ExtensionSet}),
793 critical BOOLEAN DEFAULT FALSE,
794 extnValue OCTET STRING
795 -- contains a DER encoding of a value of type &ExtnType
796 -- for the extension object identified by extnId -- }
798 EXTENSION.&id denotes an OBJECT IDENTIFIER and ({ExtensionSet})
799 constrains the OBJECT IDENTIFIER to be the identifier of a supported
800 certificate extension.
802 The component reference "extnValue" on Extension refers to a
803 component type of OCTET STRING. The corresponding component values
804 will be OCTET STRING values. The component reference
805 "extnValue.content" on Extension refers to the type of the contained
806 type, which in this case is an open type.
808 One of the X.509 [11] standard extensions is basicConstraints, which
809 is identified with the OBJECT IDENTIFIER 2.5.29.19 and is defined to
810 have the following syntax.
812 BasicConstraintsSyntax ::= SEQUENCE {
813 cA BOOLEAN DEFAULT FALSE,
814 pathLenConstraint INTEGER (0..MAX) OPTIONAL }
816 The component reference "extnValue.content.(2.5.29.19)" on Extension
817 specifies a BasicConstraintsSyntax extension value and the component
818 reference "extnValue.content.(2.5.29.19).cA" identifies the cA
819 component of a BasicConstraintsSyntax extension value.
821 3.2. Matching of Components
823 The rule in a ComponentAssertion specifies how the zero, one or more
824 component values identified by the component reference are tested by
825 the assertion. Attribute matching rules are used to specify the
826 semantics of the test.
828 Each matching rule has a notional set of attribute syntaxes
829 (typically one), defined as ASN.1 types, to which it may be applied.
830 When used in a ComponentAssertion these matching rules apply to the
831 same ASN.1 types, only in this context the corresponding ASN.1 values
832 are not necessarily complete attribute values.
834 Note that the referenced component type may be a tagged and/or
835 constrained version of the expected attribute syntax (e.g.,
836 [0] INTEGER, whereas integerMatch would expect simply INTEGER), or an
837 open type. Additional type substitutions of the kind described in
842 Legg Standards Track [Page 15]
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844 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
847 Section 3.1.1 are performed as required to reduce the component type
848 to the same type as the attribute syntax expected by the matching
849 rule.
851 If a matching rule applies to more than one attribute syntax (e.g.,
852 objectIdentifierFirstComponentMatch [12]) then the minimum number of
853 substitutions required to conform to any one of those syntaxes is
854 performed. If a matching rule can apply to any attribute syntax
855 (e.g., the allComponentsMatch rule defined in Section 6.2) then the
856 referenced component type is used as is, with no additional
857 substitutions.
859 The value in a ComponentAssertion will be of the assertion syntax
860 (i.e., ASN.1 type) required by the chosen matching rule. Note that
861 the assertion syntax of a matching rule is not necessarily the same
862 as the attribute syntax(es) to which the rule may be applied.
864 Some matching rules do not have a fixed assertion syntax (e.g.,
865 allComponentsMatch). The required assertion syntax is determined in
866 each instance of use by the syntax of the attribute type to which the
867 matching rule is applied. For these rules the ASN.1 type of the
868 referenced component is used in place of an attribute syntax to
869 decide the required assertion syntax.
871 The ComponentAssertion is Undefined if:
873 a) the matching rule in the ComponentAssertion is not known to the
874 evaluating procedure,
876 b) the matching rule is not applicable to the referenced component
877 type, even with the additional type substitutions,
879 c) the value in the ComponentAssertion does not conform to the
880 assertion syntax defined for the matching rule,
882 d) some part of the component reference identifies an open type in
883 the tested value that cannot be decoded, or
885 e) the implementation does not support the particular combination of
886 component reference and matching rule.
888 If the ComponentAssertion is not Undefined then the
889 ComponentAssertion evaluates to TRUE if there is at least one
890 component value for which the matching rule applied to that component
891 value returns TRUE, and evaluates to FALSE otherwise (which includes
892 the case where there are no component values).
898 Legg Standards Track [Page 16]
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900 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
903 3.2.1. Applicability of Existing Matching Rules
905 3.2.1.1. String Matching
907 ASN.1 has a number of built in restricted character string types with
908 different character sets and/or different character encodings. A
909 directory user generally has little interest in the particular
910 character set or encoding used to represent a character string
911 component value, and some directory server implementations make no
912 distinction between the different string types in their internal
913 representation of values. So rather than define string matching
914 rules for each of the restricted character string types, the existing
915 case ignore and case exact string matching rules are extended to
916 apply to component values of any of the restricted character string
917 types and any ChoiceOfStrings type [9], in addition to component
918 values of the DirectoryString type. This extension is only for the
919 purposes of component matching described in this document.
921 The relevant string matching rules are: caseIgnoreMatch,
922 caseIgnoreOrderingMatch, caseIgnoreSubstringsMatch, caseExactMatch,
923 caseExactOrderingMatch and caseExactSubstringsMatch. The relevant
924 restricted character string types are: NumericString,
925 PrintableString, VisibleString, IA5String, UTF8String, BMPString,
926 UniversalString, TeletexString, VideotexString, GraphicString and
927 GeneralString. A ChoiceOfStrings type is a purely syntactic CHOICE
928 of these ASN.1 string types. Note that GSER [9] declares each and
929 every use of the DirectoryString{} parameterized type to be a
930 ChoiceOfStrings type.
932 The assertion syntax of the string matching rules is still
933 DirectoryString regardless of the string syntax of the component
934 being matched. Thus an implementation will be called upon to compare
935 a DirectoryString value to a value of one of the restricted character
936 string types, or a ChoiceOfStrings type. As is the case when
937 comparing two DirectoryStrings where the chosen alternatives are of
938 different string types, the comparison proceeds so long as the
939 corresponding characters are representable in both character sets.
940 Otherwise matching returns FALSE.
942 3.2.1.2. Telephone Number Matching
944 Early editions of X.520 [12] gave the syntax of the telephoneNumber
945 attribute as a constrained PrintableString. The fourth edition of
946 X.520 equates the ASN.1 type name TelephoneNumber to the constrained
947 PrintableString and uses TelephoneNumber as the attribute and
948 assertion syntax. For the purposes of component matching,
954 Legg Standards Track [Page 17]
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956 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
959 telephoneNumberMatch and telephoneNumberSubstringsMatch are permitted
960 to be applied to any PrintableString value, as well as to
961 TelephoneNumber values.
963 3.2.1.3. Distinguished Name Matching
965 The DistinguishedName type is defined by assignment to be the same as
966 the RDNSequence type, however RDNSequence is sometimes directly used
967 in other type definitions. For the purposes of component matching,
968 distinguishedNameMatch is also permitted to be applied to values of
969 the RDNSequence type.
971 3.2.2. Additional Useful Matching Rules
973 This section defines additional matching rules that may prove useful
974 in ComponentAssertions. These rules may also be used in
975 extensibleMatch search filters [3].
977 3.2.2.1. The rdnMatch Matching Rule
979 The distinguishedNameMatch matching rule can match whole
980 distinguished names but it is sometimes useful to be able to match
981 specific Relative Distinguished Names (RDNs) in a Distinguished Name
982 (DN) without regard for the other RDNs in the DN. The rdnMatch
983 matching rule allows component RDNs of a DN to be tested.
985 The LDAP-style definitions for rdnMatch and its assertion syntax are:
987 ( 1.2.36.79672281.1.13.3 NAME 'rdnMatch'
988 SYNTAX 1.2.36.79672281.1.5.0 )
990 ( 1.2.36.79672281.1.5.0 DESC 'RDN' )
992 The LDAP-specific encoding for a value of the RDN syntax is given by
993 the <RelativeDistinguishedNameValue> rule [9].
995 The X.500-style definition for rdnMatch is:
997 rdnMatch MATCHING-RULE ::= {
998 SYNTAX RelativeDistinguishedName
999 ID { 1 2 36 79672281 1 13 3 } }
1001 The rdnMatch rule evaluates to true if the component value and
1002 assertion value are the same RDN, using the same RDN comparison
1003 method as distinguishedNameMatch.
1010 Legg Standards Track [Page 18]
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1012 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1015 When using rdnMatch to match components of DNs it is important to
1016 note that the LDAP-specific encoding of a DN [5] reverses the order
1017 of the RDNs. So for the DN represented in LDAP as
1018 "cn=Steven Legg,o=Adacel,c=AU", the RDN "cn=Steven Legg" corresponds
1019 to the component reference "3", or alternatively, "-1".
1021 3.2.2.2. The presentMatch Matching Rule
1023 At times it would be useful to test not if a specific value of a
1024 particular component is present, but whether any value of a
1025 particular component is present. The presentMatch matching rule
1026 allows the presence of a particular component value to be tested.
1028 The LDAP-style definitions for presentMatch and its assertion syntax
1029 are:
1031 ( 1.2.36.79672281.1.13.5 NAME 'presentMatch'
1032 SYNTAX 1.2.36.79672281.1.5.1 )
1034 ( 1.2.36.79672281.1.5.1 DESC 'NULL' )
1036 The LDAP-specific encoding for a value of the NULL syntax is given by
1037 the <NullValue> rule [9].
1039 The X.500-style definition for presentMatch is:
1041 presentMatch MATCHING-RULE ::= {
1042 SYNTAX NULL
1043 ID { 1 2 36 79672281 1 13 5 } }
1045 When used in a extensible match filter item, presentMatch behaves
1046 like the "present" case of a regular search filter. In a
1047 ComponentAssertion, presentMatch evaluates to TRUE if and only if the
1048 component reference identifies one or more component values,
1049 regardless of the actual component value contents. Note that if
1050 useDefaultValues is TRUE then the identified component values may be
1051 (part of) a DEFAULT value.
1053 The notional count referenced by the <count> form of ComponentId is
1054 taken to be present if the SET OF value is present, and absent
1055 otherwise. Note that in ASN.1 notation an absent SET OF value is
1056 distinctly different from a SET OF value that is present but empty.
1057 It is up to the specification using the ASN.1 notation to decide
1058 whether the distinction matters. Often an empty SET OF component and
1059 an absent SET OF component are treated as semantically equivalent.
1060 If a SET OF value is present, but empty, a presentMatch on the SET OF
1061 component SHALL return TRUE and the notional count SHALL be regarded
1062 as present and equal to zero.
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1068 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1071 3.2.3. Summary of Useful Matching Rules
1073 The following is a non-exhaustive list of useful matching rules and
1074 the ASN.1 types to which they can be applied, taking account of all
1075 the extensions described in Section 3.2.1, and the new matching rules
1076 defined in Section 3.2.2.
1078 +================================+==============================+
1079 | Matching Rule | ASN.1 Type |
1080 +================================+==============================+
1081 | bitStringMatch | BIT STRING |
1082 +--------------------------------+------------------------------+
1083 | booleanMatch | BOOLEAN |
1084 +--------------------------------+------------------------------+
1085 | caseIgnoreMatch | NumericString |
1086 | caseIgnoreOrderingMatch | PrintableString |
1087 | caseIgnoreSubstringsMatch | VisibleString (ISO646String) |
1088 | caseExactMatch | IA5String |
1089 | caseExactOrderingMatch | UTF8String |
1090 | caseExactSubstringsMatch | BMPString (UCS-2, UNICODE) |
1091 | | UniversalString (UCS-4) |
1092 | | TeletexString (T61String) |
1093 | | VideotexString |
1094 | | GraphicString |
1095 | | GeneralString |
1096 | | any ChoiceOfStrings type |
1097 +--------------------------------+------------------------------+
1098 | caseIgnoreIA5Match | IA5String |
1099 | caseExactIA5Match | |
1100 +--------------------------------+------------------------------+
1101 | distinguishedNameMatch | DistinguishedName |
1102 | | RDNSequence |
1103 +--------------------------------+------------------------------+
1104 | generalizedTimeMatch | GeneralizedTime |
1105 | generalizedTimeOrderingMatch | |
1106 +--------------------------------+------------------------------+
1107 | integerMatch | INTEGER |
1108 | integerOrderingMatch | |
1109 +--------------------------------+------------------------------+
1110 | numericStringMatch | NumericString |
1111 | numericStringOrderingMatch | |
1112 | numericStringSubstringsMatch | |
1113 +--------------------------------+------------------------------+
1114 | objectIdentifierMatch | OBJECT IDENTIFIER |
1115 +--------------------------------+------------------------------+
1116 | octetStringMatch | OCTET STRING |
1117 | octetStringOrderingMatch | |
1118 | octetStringSubstringsMatch | |
1122 Legg Standards Track [Page 20]
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1124 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1127 +--------------------------------+------------------------------+
1128 | presentMatch | any ASN.1 type |
1129 +--------------------------------+------------------------------+
1130 | rdnMatch | RelativeDistinguishedName |
1131 +--------------------------------+------------------------------+
1132 | telephoneNumberMatch | PrintableString |
1133 | telephoneNumberSubstringsMatch | TelephoneNumber |
1134 +--------------------------------+------------------------------+
1135 | uTCTimeMatch | UTCTime |
1136 | uTCTimeOrderingMatch | |
1137 +--------------------------------+------------------------------+
1139 Note that the allComponentsMatch matching rule defined in Section 6.2
1140 can be used for equality matching of values of the ENUMERATED, NULL,
1141 REAL and RELATIVE-OID ASN.1 types, among other things.
1143 4. ComponentFilter
1145 The ComponentAssertion allows the value(s) of any one component type
1146 in a complex ASN.1 type to be matched, but there is often a desire to
1147 match the values of more than one component type. A ComponentFilter
1148 is an assertion about the presence, or values of, multiple components
1149 within an ASN.1 value.
1151 The ComponentFilter assertion, an expression of ComponentAssertions,
1152 evaluates to either TRUE, FALSE or Undefined for each tested ASN.1
1153 value.
1155 A ComponentFilter is described by the following ASN.1 type (assumed
1156 to be defined with "EXPLICIT TAGS" in force):
1158 ComponentFilter ::= CHOICE {
1159 item [0] ComponentAssertion,
1160 and [1] SEQUENCE OF ComponentFilter,
1161 or [2] SEQUENCE OF ComponentFilter,
1162 not [3] ComponentFilter }
1164 Note: despite the use of SEQUENCE OF instead of SET OF for the "and"
1165 and "or" alternatives in ComponentFilter, the order of the component
1166 filters is not significant.
1168 A ComponentFilter that is a ComponentAssertion evaluates to TRUE if
1169 the ComponentAssertion is TRUE, evaluates to FALSE if the
1170 ComponentAssertion is FALSE, and evaluates to Undefined otherwise.
1178 Legg Standards Track [Page 21]
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1180 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1183 The "and" of a sequence of component filters evaluates to TRUE if the
1184 sequence is empty or if each component filter evaluates to TRUE,
1185 evaluates to FALSE if at least one component filter is FALSE, and
1186 evaluates to Undefined otherwise.
1188 The "or" of a sequence of component filters evaluates to FALSE if the
1189 sequence is empty or if each component filter evaluates to FALSE,
1190 evaluates to TRUE if at least one component filter is TRUE, and
1191 evaluates to Undefined otherwise.
1193 The "not" of a component filter evaluates to TRUE if the component
1194 filter is FALSE, evaluates to FALSE if the component filter is TRUE,
1195 and evaluates to Undefined otherwise.
1197 5. The componentFilterMatch Matching Rule
1199 The componentFilterMatch matching rule allows a ComponentFilter to be
1200 applied to an attribute value. The result of the matching rule is
1201 the result of applying the ComponentFilter to the attribute value.
1203 The LDAP-style definitions for componentFilterMatch and its assertion
1204 syntax are:
1206 ( 1.2.36.79672281.1.13.2 NAME 'componentFilterMatch'
1207 SYNTAX 1.2.36.79672281.1.5.2 )
1209 ( 1.2.36.79672281.1.5.2 DESC 'ComponentFilter' )
1211 The LDAP-specific encoding for the ComponentFilter assertion syntax
1212 is specified by GSER [9].
1214 As a convenience to implementors, an equivalent ABNF description of
1215 the GSER encoding for ComponentFilter is provided here. In the event
1216 that there is a discrepancy between this ABNF and the encoding
1217 determined by GSER, GSER is to be taken as definitive. The GSER
1218 encoding of a ComponentFilter is described by the following
1219 equivalent ABNF:
1221 ComponentFilter = filter-item /
1222 and-filter /
1223 or-filter /
1224 not-filter
1226 filter-item = item-chosen ComponentAssertion
1227 and-filter = and-chosen SequenceOfComponentFilter
1228 or-filter = or-chosen SequenceOfComponentFilter
1229 not-filter = not-chosen ComponentFilter
1234 Legg Standards Track [Page 22]
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1236 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1239 item-chosen = %x69.74.65.6D.3A ; "item:"
1240 and-chosen = %x61.6E.64.3A ; "and:"
1241 or-chosen = %x6F.72.3A ; "or:"
1242 not-chosen = %x6E.6F.74.3A ; "not:"
1244 SequenceOfComponentFilter = "{" [ sp ComponentFilter
1245 *( "," sp ComponentFilter) ] sp "}"
1247 ComponentAssertion = "{" [ sp component "," ]
1248 [ sp useDefaultValues "," ]
1249 sp rule ","
1250 sp assertion-value sp "}"
1251 component = component-label msp StringValue
1252 useDefaultValues = use-defaults-label msp BooleanValue
1253 rule = rule-label msp ObjectIdentifierValue
1254 assertion-value = value-label msp Value
1256 component-label = %x63.6F.6D.70.6F.6E.65.6E.74 ; "component"
1257 use-defaults-label = %x75.73.65.44.65.66.61.75.6C.74.56.61.6C.75
1258 %x65.73 ; "useDefaultValues"
1259 rule-label = %x72.75.6C.65 ; "rule"
1260 value-label = %x76.61.6C.75.65 ; "value"
1262 sp = *%x20 ; zero, one or more space characters
1263 msp = 1*%x20 ; one or more space characters
1265 The ABNF for <Value>, <StringValue>, <ObjectIdentifierValue> and
1266 <BooleanValue> is defined by GSER [9].
1268 The ABNF descriptions of LDAP-specific encodings for attribute
1269 syntaxes typically do not clearly or consistently delineate the
1270 component parts of an attribute value. A regular and uniform
1271 character string encoding for arbitrary component data types is
1272 needed to encode the assertion value in a ComponentAssertion. The
1273 <Value> rule from GSER provides a human readable text encoding for a
1274 component value of any arbitrary ASN.1 type.
1276 The X.500-style definition [10] for componentFilterMatch is:
1278 componentFilterMatch MATCHING-RULE ::= {
1279 SYNTAX ComponentFilter
1280 ID { 1 2 36 79672281 1 13 2 } }
1282 A ComponentAssertion can potentially use any matching rule, including
1283 componentFilterMatch, so componentFilterMatch may be nested. The
1284 component references in a nested componentFilterMatch are relative to
1290 Legg Standards Track [Page 23]
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1292 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1295 the component corresponding to the containing ComponentAssertion. In
1296 Section 7, an example search on the seeAlso attribute shows this
1297 usage.
1299 6. Equality Matching of Complex Components
1301 It is possible to test if an attribute value of a complex ASN.1
1302 syntax is the same as some purported (i.e., assertion) value by using
1303 a complicated ComponentFilter that tests if corresponding components
1304 are the same. However, it would be more convenient to be able to
1305 present a whole assertion value to a matching rule that could do the
1306 component-wise comparison of an attribute value with the assertion
1307 value for any arbitrary attribute syntax. Similarly, the ability to
1308 do a straightforward equality comparison of a component value that is
1309 itself of a complex ASN.1 type would also be convenient.
1311 It would be difficult to define a single matching rule that
1312 simultaneously satisfies all notions of what the equality matching
1313 semantics should be. For example, in some instances a case sensitive
1314 comparison of string components may be preferable to a case
1315 insensitive comparison. Therefore a basic equality matching rule,
1316 allComponentsMatch, is defined in Section 6.2, and the means to
1317 derive new matching rules from it with slightly different equality
1318 matching semantics are described in Section 6.3.
1320 The directoryComponentsMatch defined in Section 6.4 is a derivation
1321 of allComponentsMatch that suits typical uses of the directory.
1322 Other specifications are free to derive new rules from
1323 allComponentsMatch or directoryComponentsMatch, that suit their usage
1324 of the directory.
1326 The allComponentsMatch rule, the directoryComponentsMatch rule and
1327 any matching rules derived from them are collectively called
1328 component equality matching rules.
1330 6.1. The OpenAssertionType Syntax
1332 The component equality matching rules have a variable assertion
1333 syntax. In X.500 this is indicated by omitting the optional SYNTAX
1334 field in the MATCHING-RULE information object. The assertion syntax
1335 then defaults to the target attribute's syntax in actual usage,
1336 unless the description of the matching rule says otherwise. The
1337 SYNTAX field in the LDAP-specific encoding of a
1338 MatchingRuleDescription is mandatory, so the OpenAssertionType syntax
1339 is defined to fill the same role. That is, the OpenAssertionType
1340 syntax is semantically equivalent to an omitted SYNTAX field in an
1341 X.500 MATCHING-RULE information object. OpenAssertionType MUST NOT
1342 be used as the attribute syntax in an attribute type definition.
1346 Legg Standards Track [Page 24]
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1348 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1351 Unless explicitly varied by the description of a particular matching
1352 rule, if an OpenAssertionType assertion value appears in a
1353 ComponentAssertion its LDAP-specific encoding is described by the
1354 <Value> rule in GSER [9], otherwise its LDAP-specific encoding is the
1355 encoding defined for the syntax of the attribute type to which the
1356 matching rule with the OpenAssertionType assertion syntax is applied.
1358 The LDAP definition for the OpenAssertionType syntax is:
1360 ( 1.2.36.79672281.1.5.3 DESC 'OpenAssertionType' )
1362 6.2. The allComponentsMatch Matching Rule
1364 The LDAP-style definition for allComponentsMatch is:
1366 ( 1.2.36.79672281.1.13.6 NAME 'allComponentsMatch'
1367 SYNTAX 1.2.36.79672281.1.5.3 )
1369 The X.500-style definition for allComponentsMatch is:
1371 allComponentsMatch MATCHING-RULE ::= {
1372 ID { 1 2 36 79672281 1 13 6 } }
1374 When allComponentsMatch is used in a ComponentAssertion the assertion
1375 syntax is the same as the ASN.1 type of the identified component.
1376 Otherwise, the assertion syntax of allComponentsMatch is the same as
1377 the attribute syntax of the attribute to which the matching rule is
1378 applied.
1380 Broadly speaking, this matching rule evaluates to true if and only if
1381 corresponding components of the assertion value and the attribute or
1382 component value are the same.
1384 In detail, equality is determined by the following cases applied
1385 recursively.
1387 a) Two values of a SET or SEQUENCE type are the same if and only if,
1388 for each component type, the corresponding component values are
1389 either,
1391 1) both absent,
1393 2) both present and the same, or
1395 3) absent or the same as the DEFAULT value for the component, if a
1396 DEFAULT value is defined.
1402 Legg Standards Track [Page 25]
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1404 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1407 Values of an EMBEDDED PDV, EXTERNAL, unrestricted CHARACTER
1408 STRING, or INSTANCE OF type are compared according to their
1409 respective associated SEQUENCE type (see Section 3.1.2).
1411 b) Two values of a SEQUENCE OF type are the same if and only if, the
1412 values have the same number of (possibly duplicated) instances and
1413 corresponding instances are the same.
1415 c) Two values of a SET OF type are the same if and only if, the
1416 values have the same number of instances and each distinct
1417 instance occurs in both values the same number of times, i.e.,
1418 both values have the same instances, including duplicates, but in
1419 any order.
1421 d) Two values of a CHOICE type are the same if and only if, both
1422 values are of the same chosen alternative and the component values
1423 are the same.
1425 e) Two BIT STRING values are the same if and only if the values have
1426 the same number of bits and corresponding bits are the same. If
1427 the BIT STRING type is defined with a named bit list then trailing
1428 zero bits in the values are treated as absent for the purposes of
1429 this comparison.
1431 f) Two BOOLEAN values are the same if and only if both are TRUE or
1432 both are FALSE.
1434 g) Two values of a string type are the same if and only if the values
1435 have the same number of characters and corresponding characters
1436 are the same. Letter case is significant. For the purposes of
1437 allComponentsMatch, the string types are NumericString,
1438 PrintableString, TeletexString (T61String), VideotexString,
1439 IA5String, GraphicString, VisibleString (ISO646String),
1440 GeneralString, UniversalString, BMPString, UTF8String,
1441 GeneralizedTime, UTCTime and ObjectDescriptor.
1443 h) Two INTEGER values are the same if and only if the integers are
1444 equal.
1446 i) Two ENUMERATED values are the same if and only if the enumeration
1447 item identifiers are the same (equivalently, if the integer values
1448 associated with the identifiers are equal).
1450 j) Two NULL values are always the same, unconditionally.
1452 k) Two OBJECT IDENTIFIER values are the same if and only if the
1453 values have the same number of arcs and corresponding arcs are the
1454 same.
1458 Legg Standards Track [Page 26]
1459 \f
1460 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1463 l) Two OCTET STRING values are the same if and only if the values
1464 have the same number of octets and corresponding octets are the
1465 same.
1467 m) Two REAL values are the same if and only if they are both the same
1468 special value, or neither is a special value and they have the
1469 same base and represent the same real number. The special values
1470 for REAL are zero, PLUS-INFINITY and MINUS-INFINITY.
1472 n) Two RELATIVE-OID values are the same if and only if the values
1473 have the same number of arcs and corresponding arcs are the same.
1474 The respective starting nodes for the RELATIVE-OID values are
1475 disregarded in the comparison, i.e., they are assumed to be the
1476 same.
1478 o) Two values of an open type are the same if and only if both are of
1479 the same ASN.1 type and are the same according to that type. If
1480 the actual ASN.1 type of the values is unknown then the
1481 allComponentsMatch rule evaluates to Undefined.
1483 Tags and constraints, being part of the type definition and not part
1484 of the abstract values, are ignored for matching purposes.
1486 The allComponentsMatch rule may be used as the defined equality
1487 matching rule for an attribute.
1489 6.3. Deriving Component Equality Matching Rules
1491 A new component equality matching rule with more refined matching
1492 semantics may be derived from allComponentsMatch, or any other
1493 component equality matching rule, using the convention described in
1494 this section.
1496 The matching behaviour of a derived component equality matching rule
1497 is specified by nominating, for each of one or more identified
1498 components, a commutative equality matching rule that will be used to
1499 match values of that component. This overrides the matching that
1500 would otherwise occur for values of that component using the base
1501 rule for the derivation. These overrides can be conveniently
1502 represented as rows in a table of the following form.
1504 Component | Matching Rule
1505 ============+===============
1506 |
1507 |
1514 Legg Standards Track [Page 27]
1515 \f
1516 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1519 Usually, all component values of a particular ASN.1 type are to be
1520 matched the same way. An ASN.1 type reference (e.g.,
1521 DistinguishedName) or an ASN.1 built-in type name (e.g., INTEGER) in
1522 the Component column of the table specifies that the nominated
1523 equality matching rule is to be applied to all values of the named
1524 type, regardless of context.
1526 An ASN.1 type reference with a component reference appended
1527 (separated by a ".") specifies that the nominated matching rule
1528 applies only to the identified components of values of the named
1529 type. Other component values that happen to be of the same ASN.1
1530 type are not selected.
1532 Additional type substitutions as described in Section 3.2 are assumed
1533 to be performed to align the component type with the matching rule
1534 assertion syntax.
1536 Conceptually, the rows in a table for the base rule are appended to
1537 the rows in the table for a derived rule for the purpose of deciding
1538 the matching semantics of the derived rule. Notionally,
1539 allComponentsMatch has an empty table.
1541 A row specifying values of an outer containing type (e.g.,
1542 DistinguishedName) takes precedence over a row specifying values of
1543 an inner component type (e.g., RelativeDistinguishedName), regardless
1544 of their order in the table. Specifying a row for component values
1545 of an inner type is only useful if a value of the type can also
1546 appear on its own, or as a component of values of a different outer
1547 type. For example, if there is a row for DistinguishedName then a
1548 row for RelativeDistinguishedName can only ever apply to
1549 RelativeDistinguishedName component values that are not part of a
1550 DistinguishedName. A row for values of an outer type in the table
1551 for the base rule takes precedence over a row for values of an inner
1552 type in the table for the derived rule.
1554 Where more than one row applies to a particular component value the
1555 earlier row takes precedence over the later row. Thus rows in the
1556 table for the derived rule take precedence over any rows for the same
1557 component in the table for the base rule.
1559 6.4. The directoryComponentsMatch Matching Rule
1561 The directoryComponentsMatch matching rule is derived from the
1562 allComponentsMatch matching rule.
1570 Legg Standards Track [Page 28]
1571 \f
1572 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1575 The LDAP-style definition for directoryComponentsMatch is:
1577 ( 1.2.36.79672281.1.13.7 NAME 'directoryComponentsMatch'
1578 SYNTAX 1.2.36.79672281.1.5.3 )
1580 The X.500-style definition for directoryComponentsMatch is:
1582 directoryComponentsMatch MATCHING-RULE ::= {
1583 ID { 1 2 36 79672281 1 13 7 } }
1585 The matching semantics of directoryComponentsMatch are described by
1586 the following table, using the convention described in Section 6.3.
1588 ASN.1 Type | Matching Rule
1589 =========================================+========================
1590 RDNSequence | distinguishedNameMatch
1591 RelativeDistinguishedName | rdnMatch
1592 TelephoneNumber | telephoneNumberMatch
1593 FacsimileTelephoneNumber.telephoneNumber | telephoneNumberMatch
1594 NumericString | numericStringMatch
1595 GeneralizedTime | generalizedTimeMatch
1596 UTCTime | uTCTimeMatch
1597 DirectoryString{} | caseIgnoreMatch
1598 BMPString | caseIgnoreMatch
1599 GeneralString | caseIgnoreMatch
1600 GraphicString | caseIgnoreMatch
1601 IA5String | caseIgnoreMatch
1602 PrintableString | caseIgnoreMatch
1603 TeletexString | caseIgnoreMatch
1604 UniversalString | caseIgnoreMatch
1605 UTF8String | caseIgnoreMatch
1606 VideotexString | caseIgnoreMatch
1607 VisibleString | caseIgnoreMatch
1609 Notes:
1611 1) The DistinguishedName type is defined by assignment to be the same
1612 as the RDNSequence type. Some types (e.g., Name and LocalName)
1613 directly reference RDNSequence rather than DistinguishedName.
1614 Specifying RDNSequence captures all these DN-like types.
1616 2) A RelativeDistinguishedName value is only matched by rdnMatch if
1617 it is not part of an RDNSequence value.
1619 3) The telephone number component of the FacsimileTelephoneNumber
1620 ASN.1 type [12] is defined as a constrained PrintableString.
1621 PrintableString component values that are part of a
1622 FacsimileTelephoneNumber value can be identified separately from
1626 Legg Standards Track [Page 29]
1627 \f
1628 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1631 other components of PrintableString type by the specifier
1632 FacsimileTelephoneNumber.telephoneNumber, so that
1633 telephoneNumberMatch can be selectively applied. The fourth
1634 edition of X.520 defines the telephoneNumber component of
1635 FacsimileTelephoneNumber to be of the type TelephoneNumber, making
1636 the row for FacsimileTelephoneNumber.telephoneNumber components
1637 redundant.
1639 The directoryComponentsMatch rule may be used as the defined equality
1640 matching rule for an attribute.
1642 7. Component Matching Examples
1644 This section contains examples of search filters using the
1645 componentFilterMatch matching rule. The filters are described using
1646 the string representation of LDAP search filters [18]. Note that
1647 this representation requires asterisks to be escaped in assertion
1648 values (in these examples the assertion values are all
1649 <ComponentAssertion> encodings). The asterisks have not been escaped
1650 in these examples for the sake of clarity, and to avoid confusing the
1651 protocol representation of LDAP search filter assertion values, where
1652 such escaping does not apply. Line breaks and indenting have been
1653 added only as an aid to readability.
1655 The example search filters using componentFilterMatch are all single
1656 extensible match filter items, though there is no reason why
1657 componentFilterMatch can't be used in more complicated search
1658 filters.
1660 The first examples describe searches over the objectClasses schema
1661 operational attribute, which has an attribute syntax described by the
1662 ASN.1 type ObjectClassDescription [10], and holds the definitions of
1663 the object classes known to a directory server. The definition of
1664 ObjectClassDescription is as follows:
1666 ObjectClassDescription ::= SEQUENCE {
1667 identifier OBJECT-CLASS.&id,
1668 name SET OF DirectoryString {ub-schema} OPTIONAL,
1669 description DirectoryString {ub-schema} OPTIONAL,
1670 obsolete BOOLEAN DEFAULT FALSE,
1671 information [0] ObjectClassInformation }
1673 ObjectClassInformation ::= SEQUENCE {
1674 subclassOf SET OF OBJECT-CLASS.&id OPTIONAL,
1675 kind ObjectClassKind DEFAULT structural,
1676 mandatories [3] SET OF ATTRIBUTE.&id OPTIONAL,
1677 optionals [4] SET OF ATTRIBUTE.&id OPTIONAL }
1682 Legg Standards Track [Page 30]
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1684 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1687 ObjectClassKind ::= ENUMERATED {
1688 abstract (0),
1689 structural (1),
1690 auxiliary (2) }
1692 OBJECT-CLASS.&id and ATTRIBUTE.&id are equivalent to the OBJECT
1693 IDENTIFIER ASN.1 type. A value of OBJECT-CLASS.&id is an OBJECT
1694 IDENTIFIER for an object class. A value of ATTRIBUTE.&id is an
1695 OBJECT IDENTIFIER for an attribute type.
1697 The following search filter finds the object class definition for the
1698 object class identified by the OBJECT IDENTIFIER 2.5.6.18:
1700 (objectClasses:componentFilterMatch:=
1701 item:{ component "identifier",
1702 rule objectIdentifierMatch, value 2.5.6.18 })
1704 A match on the "identifier" component of objectClasses values is
1705 equivalent to the objectIdentifierFirstComponentMatch matching rule
1706 applied to attribute values of the objectClasses attribute type. The
1707 componentFilterMatch matching rule subsumes the functionality of the
1708 objectIdentifierFirstComponentMatch, integerFirstComponentMatch and
1709 directoryStringFirstComponentMatch matching rules.
1711 The following search filter finds the object class definition for the
1712 object class called foobar:
1714 (objectClasses:componentFilterMatch:=
1715 item:{ component "name.*",
1716 rule caseIgnoreMatch, value "foobar" })
1718 An object class definition can have multiple names and the above
1719 filter will match an objectClasses value if any one of the names is
1720 "foobar".
1722 The component reference "name.0" identifies the notional count of the
1723 number of names in an object class definition. The following search
1724 filter finds object class definitions with exactly one name:
1726 (objectClasses:componentFilterMatch:=
1727 item:{ component "name.0", rule integerMatch, value 1 })
1729 The "description" component of an ObjectClassDescription is defined
1730 to be an OPTIONAL DirectoryString. The following search filter finds
1731 object class definitions that have descriptions, regardless of the
1732 contents of the description string:
1738 Legg Standards Track [Page 31]
1739 \f
1740 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1743 (objectClasses:componentFilterMatch:=
1744 item:{ component "description",
1745 rule presentMatch, value NULL })
1747 The presentMatch returns TRUE if the description component is present
1748 and FALSE otherwise.
1750 The following search filter finds object class definitions that don't
1751 have descriptions:
1753 (objectClasses:componentFilterMatch:=
1754 not:item:{ component "description",
1755 rule presentMatch, value NULL })
1757 The following search filter finds object class definitions with the
1758 word "bogus" in the description:
1760 (objectClasses:componentFilterMatch:=
1761 item:{ component "description",
1762 rule caseIgnoreSubstringsMatch,
1763 value { any:"bogus" } })
1765 The assertion value is of the SubstringAssertion syntax, i.e.,
1767 SubstringAssertion ::= SEQUENCE OF CHOICE {
1768 initial [0] DirectoryString {ub-match},
1769 any [1] DirectoryString {ub-match},
1770 final [2] DirectoryString {ub-match} }
1772 The "obsolete" component of an ObjectClassDescription is defined to
1773 be DEFAULT FALSE. An object class is obsolete if the "obsolete"
1774 component is present and set to TRUE. The following search filter
1775 finds all obsolete object classes:
1777 (objectClasses:componentFilterMatch:=
1778 item:{ component "obsolete", rule booleanMatch, value TRUE })
1780 An object class is not obsolete if the "obsolete" component is not
1781 present, in which case it defaults to FALSE, or is present but is
1782 explicitly set to FALSE. The following search filter finds all non-
1783 obsolete object classes:
1785 (objectClasses:componentFilterMatch:=
1786 item:{ component "obsolete", rule booleanMatch, value FALSE })
1788 The useDefaultValues flag in the ComponentAssertion defaults to TRUE
1789 so the componentFilterMatch rule treats an absent "obsolete"
1790 component as being present and set to FALSE. The following search
1794 Legg Standards Track [Page 32]
1795 \f
1796 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1799 filter finds only object class definitions where the "obsolete"
1800 component has been explicitly set to FALSE, rather than implicitly
1801 defaulting to FALSE:
1803 (objectClasses:componentFilterMatch:=
1804 item:{ component "obsolete", useDefaultValues FALSE,
1805 rule booleanMatch, value FALSE })
1807 With the useDefaultValues flag set to FALSE, if the "obsolete"
1808 component is absent the component reference identifies no component
1809 value and the matching rule will return FALSE. The matching rule can
1810 only return TRUE if the component is present and set to FALSE.
1812 The "information.kind" component of the ObjectClassDescription is an
1813 ENUMERATED type. The allComponentsMatch matching rule can be used to
1814 match values of an ENUMERATED type. The following search filter
1815 finds object class definitions for auxiliary object classes:
1817 (objectClasses:componentFilterMatch:=
1818 item:{ component "information.kind",
1819 rule allComponentsMatch, value auxiliary })
1821 The following search filter finds auxiliary object classes with
1822 commonName (cn or 2.5.4.3) as a mandatory attribute:
1824 (objectClasses:componentFilterMatch:=and:{
1825 item:{ component "information.kind",
1826 rule allComponentsMatch, value auxiliary },
1827 item:{ component "information.mandatories.*",
1828 rule objectIdentifierMatch, value cn } })
1830 The following search filter finds auxiliary object classes with
1831 commonName as a mandatory or optional attribute:
1833 (objectClasses:componentFilterMatch:=and:{
1834 item:{ component "information.kind",
1835 rule allComponentsMatch, value auxiliary },
1836 or:{
1837 item:{ component "information.mandatories.*",
1838 rule objectIdentifierMatch, value cn },
1839 item:{ component "information.optionals.*",
1840 rule objectIdentifierMatch, value cn } } })
1842 Extra care is required when matching optional SEQUENCE OF or SET OF
1843 components because of the distinction between an absent list of
1844 instances and a present, but empty, list of instances. The following
1845 search filter finds object class definitions with less than three
1850 Legg Standards Track [Page 33]
1851 \f
1852 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1855 names, including object class definitions with a present but empty
1856 list of names, but does not find object class definitions with an
1857 absent list of names:
1859 (objectClasses:componentFilterMatch:=
1860 item:{ component "name.0",
1861 rule integerOrderingMatch, value 3 })
1863 If the "name" component is absent the "name.0" component is also
1864 considered to be absent and the ComponentAssertion evaluates to
1865 FALSE. If the "name" component is present, but empty, the "name.0"
1866 component is also present and equal to zero, so the
1867 ComponentAssertion evaluates to TRUE. To also find the object class
1868 definitions with an absent list of names the following search filter
1869 would be used:
1871 (objectClasses:componentFilterMatch:=or:{
1872 not:item:{ component "name", rule presentMatch, value NULL },
1873 item:{ component "name.0",
1874 rule integerOrderingMatch, value 3 } })
1876 Distinguished names embedded in other syntaxes can be matched with a
1877 componentFilterMatch. The uniqueMember attribute type has an
1878 attribute syntax described by the ASN.1 type NameAndOptionalUID.
1880 NameAndOptionalUID ::= SEQUENCE {
1881 dn DistinguishedName,
1882 uid UniqueIdentifier OPTIONAL }
1884 The following search filter finds values of the uniqueMember
1885 attribute containing the author's DN:
1887 (uniqueMember:componentFilterMatch:=
1888 item:{ component "dn",
1889 rule distinguishedNameMatch,
1890 value "cn=Steven Legg,o=Adacel,c=AU" })
1892 The DistinguishedName and RelativeDistinguishedName ASN.1 types are
1893 also complex ASN.1 types so the component matching rules can be
1894 applied to their inner components.
1896 DistinguishedName ::= RDNSequence
1898 RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
1900 RelativeDistinguishedName ::= SET SIZE (1..MAX) OF
1901 AttributeTypeAndValue
1906 Legg Standards Track [Page 34]
1907 \f
1908 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1911 AttributeTypeAndValue ::= SEQUENCE {
1912 type AttributeType ({SupportedAttributes}),
1913 value AttributeValue ({SupportedAttributes}{@type}) }
1915 AttributeType ::= ATTRIBUTE.&id
1917 AttributeValue ::= ATTRIBUTE.&Type
1919 ATTRIBUTE.&Type is an open type. A value of ATTRIBUTE.&Type is
1920 constrained by the type component of AttributeTypeAndValue to be of
1921 the attribute syntax of the nominated attribute type. Note: the
1922 fourth edition of X.500 extends and renames the AttributeTypeAndValue
1923 SEQUENCE type.
1925 The seeAlso attribute has the DistinguishedName syntax. The
1926 following search filter finds seeAlso attribute values containing the
1927 RDN, "o=Adacel", anywhere in the DN:
1929 (seeAlso:componentFilterMatch:=
1930 item:{ component "*", rule rdnMatch, value "o=Adacel" })
1932 The following search filter finds all seeAlso attribute values with
1933 "cn=Steven Legg" as the RDN of the named entry (i.e., the "first" RDN
1934 in an LDAPDN or the "last" RDN in an X.500 DN):
1936 (seeAlso:componentFilterMatch:=
1937 item:{ component "-1",
1938 rule rdnMatch, value "cn=Steven Legg" })
1940 The following search filter finds all seeAlso attribute values naming
1941 entries in the DIT subtree of "o=Adacel,c=AU":
1943 (seeAlso:componentFilterMatch:=and:{
1944 item:{ component "1", rule rdnMatch, value "c=AU" },
1945 item:{ component "2", rule rdnMatch, value "o=Adacel" } })
1947 The following search filter finds all seeAlso attribute values
1948 containing the naming attribute types commonName (cn) and
1949 telephoneNumber in the same RDN:
1951 (seeAlso:componentFilterMatch:=
1952 item:{ component "*", rule componentFilterMatch,
1953 value and:{
1954 item:{ component "*.type",
1955 rule objectIdentifierMatch, value cn },
1956 item:{ component "*.type",
1957 rule objectIdentifierMatch,
1958 value telephoneNumber } } })
1962 Legg Standards Track [Page 35]
1963 \f
1964 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
1967 The following search filter would find all seeAlso attribute values
1968 containing the attribute types commonName and telephoneNumber, but
1969 not necessarily in the same RDN:
1971 (seeAlso:componentFilterMatch:=and:{
1972 item:{ component "*.*.type",
1973 rule objectIdentifierMatch, value cn },
1974 item:{ component "*.*.type",
1975 rule objectIdentifierMatch, value telephoneNumber } })
1977 The following search filter finds all seeAlso attribute values
1978 containing the word "Adacel" in any organizationalUnitName (ou)
1979 attribute value in any AttributeTypeAndValue of any RDN:
1981 (seeAlso:componentFilterMatch:=
1982 item:{ component "*.*.value.(2.5.4.11)",
1983 rule caseIgnoreSubstringsMatch,
1984 value { any:"Adacel" } })
1986 The component reference "*.*.value" identifies an open type, in this
1987 case an attribute value. In a particular AttributeTypeAndValue, if
1988 the attribute type is not organizationalUnitName then the
1989 ComponentAssertion evaluates to FALSE. Otherwise the substring
1990 assertion is evaluated against the attribute value.
1992 Absent component references in ComponentAssertions can be exploited
1993 to avoid false positive matches on multi-valued attributes. For
1994 example, suppose there is a multi-valued attribute named
1995 productCodes, defined to have the Integer syntax
1996 (1.3.6.1.4.1.1466.115.121.1.27). Consider the following search
1997 filter:
1999 (&(!(productCodes:integerOrderingMatch:=3))
2000 (productCodes:integerOrderingMatch:=8))
2002 An entry whose productCodes attribute contains only the values 1 and
2003 10 will match the above filter. The first subfilter is satisfied by
2004 the value 10 (10 is not less than 3), and the second subfilter is
2005 satisfied by the value 1 (1 is less than 8). The following search
2006 filter can be used instead to only match entries that have a
2007 productCodes value in the range 3 to 7, because the ComponentFilter
2008 is evaluated against each productCodes value in isolation:
2010 (productCodes:componentFilterMatch:= and:{
2011 not:item:{ rule integerOrderingMatch, value 3 },
2012 item:{ rule integerOrderingMatch, value 8 } })
2018 Legg Standards Track [Page 36]
2019 \f
2020 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2023 An entry whose productCodes attribute contains only the values 1 and
2024 10 will not match the above filter.
2026 8. Security Considerations
2028 The component matching rules described in this document allow for a
2029 compact specification of matching capabilities that could otherwise
2030 have been defined by a plethora of specific matching rules, i.e.,
2031 despite their expressiveness and flexibility the component matching
2032 rules do not behave in a way uncharacteristic of other matching
2033 rules, so the security issues for component matching rules are no
2034 different than for any other matching rule. However, because the
2035 component matching rules are applicable to any attribute syntax,
2036 support for them in a directory server may allow searching of
2037 attributes that were previously unsearchable by virtue of there not
2038 being a suitable matching rule. Such attribute types ought to be
2039 properly protected with appropriate access controls. A generic,
2040 interoperable access control mechanism has not yet been developed,
2041 however, and implementors should be aware of the interaction of that
2042 lack with the increased risk of exposure described above.
2044 9. Acknowledgements
2046 The author would like to thank Tom Gindin for private email
2047 discussions that clarified and refined the ideas presented in this
2048 document.
2050 10. IANA Considerations
2052 The Internet Assigned Numbers Authority (IANA) has updated the LDAP
2053 descriptors registry [8] as indicated by the following templates:
2055 Subject: Request for LDAP Descriptor Registration
2056 Descriptor (short name): componentFilterMatch
2057 Object Identifier: 1.2.36.79672281.1.13.2
2058 Person & email address to contact for further information:
2059 Steven Legg <steven.legg@adacel.com.au>
2060 Usage: other (matching rule)
2061 Specification: RFC 3687
2062 Author/Change Controller: IESG
2074 Legg Standards Track [Page 37]
2075 \f
2076 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2079 Subject: Request for LDAP Descriptor Registration
2080 Descriptor (short name): rdnMatch
2081 Object Identifier: 1.2.36.79672281.1.13.3
2082 Person & email address to contact for further information:
2083 Steven Legg <steven.legg@adacel.com.au>
2084 Usage: other (matching rule)
2085 Specification: RFC 3687
2086 Author/Change Controller: IESG
2088 Subject: Request for LDAP Descriptor Registration
2089 Descriptor (short name): presentMatch
2090 Object Identifier: 1.2.36.79672281.1.13.5
2091 Person & email address to contact for further information:
2092 Steven Legg <steven.legg@adacel.com.au>
2093 Usage: other (matching rule)
2094 Specification: RFC 3687
2095 Author/Change Controller: IESG
2097 Subject: Request for LDAP Descriptor Registration
2098 Descriptor (short name): allComponentsMatch
2099 Object Identifier: 1.2.36.79672281.1.13.6
2100 Person & email address to contact for further information:
2101 Steven Legg <steven.legg@adacel.com.au>
2102 Usage: other (matching rule)
2103 Specification: RFC 3687
2104 Author/Change Controller: IESG
2106 Subject: Request for LDAP Descriptor Registration
2107 Descriptor (short name): directoryComponentsMatch
2108 Object Identifier: 1.2.36.79672281.1.13.7
2109 Person & email address to contact for further information:
2110 Steven Legg <steven.legg@adacel.com.au>
2111 Usage: other (matching rule)
2112 Specification: RFC 3687
2113 Author/Change Controller: IESG
2115 The object identifiers have been assigned for use in this
2116 specification by Adacel Technologies, under an arc assigned to Adacel
2117 by Standards Australia.
2119 11. References
2121 11.1. Normative References
2123 [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
2124 Levels", BCP 14, RFC 2119, March 1997.
2130 Legg Standards Track [Page 38]
2131 \f
2132 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2135 [2] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
2136 Specifications: ABNF", RFC 2234, November 1997.
2138 [3] Wahl, M., Howes, T. and S. Kille, "Lightweight Directory Access
2139 Protocol (v3)", RFC 2251, December 1997.
2141 [4] Wahl, M., Coulbeck, A., Howes, T. and S. Kille, "Lightweight
2142 Directory Access Protocol (v3): Attribute Syntax Definitions",
2143 RFC 2252, December 1997.
2145 [5] Wahl, M., Kille S. and T. Howes. "Lightweight Directory Access
2146 Protocol (v3): UTF-8 String Representation of Distinguished
2147 Names", RFC 2253, December 1997.
2149 [6] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD
2150 63, RFC 3629, November 2003.
2152 [7] Hodges, J. and R. Morgan, "Lightweight Directory Access
2153 Protocol (v3): Technical Specification", RFC 3377, September
2154 2002.
2156 [8] Zeilenga, K., "Internet Assigned Numbers Authority (IANA)
2157 Considerations for the Lightweight Directory Access Protocol
2158 (LDAP)", BCP 64, RFC 3383, September 2002.
2160 [9] Legg, S., "Generic String Encoding Rules (GSER) for ASN.1
2161 Types", RFC 3641, October 2003.
2163 [10] ITU-T Recommendation X.501 (1993) | ISO/IEC 9594-2:1994,
2164 Information Technology - Open Systems Interconnection - The
2165 Directory: Models
2167 [11] ITU-T Recommendation X.509 (1997) | ISO/IEC 9594-8:1998,
2168 Information Technology - Open Systems Interconnection - The
2169 Directory: Authentication Framework
2171 [12] ITU-T Recommendation X.520 (1993) | ISO/IEC 9594-6:1994,
2172 Information technology - Open Systems Interconnection - The
2173 Directory: Selected attribute types
2175 [13] ITU-T Recommendation X.680 (07/02) | ISO/IEC 8824-1:2002,
2176 Information technology - Abstract Syntax Notation One (ASN.1):
2177 Specification of basic notation
2179 [14] ITU-T Recommendation X.681 (07/02) | ISO/IEC 8824-2:2002,
2180 Information technology - Abstract Syntax Notation One (ASN.1):
2181 Information object specification
2186 Legg Standards Track [Page 39]
2187 \f
2188 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2191 [15] ITU-T Recommendation X.682 (07/02) | ISO/IEC 8824-3:2002,
2192 Information technology - Abstract Syntax Notation One (ASN.1):
2193 Constraint specification
2195 [16] ITU-T Recommendation X.683 (07/02) | ISO/IEC 8824-4:2002,
2196 Information technology - Abstract Syntax Notation One (ASN.1):
2197 Parameterization of ASN.1 specifications
2199 [17] ITU-T Recommendation X.690 (07/02) | ISO/IEC 8825-1,
2200 Information technology - ASN.1 encoding rules: Specification of
2201 Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and
2202 Distinguished Encoding Rules (DER)
2204 12.2. Informative References
2206 [18] Howes, T., "The String Representation of LDAP Search Filters",
2207 RFC 2254, December 1997.
2209 [19] ITU-T Recommendation X.500 (1993) | ISO/IEC 9594-1:1994,
2210 Information Technology - Open Systems Interconnection - The
2211 Directory: Overview of concepts, models and services
2213 12. Intellectual Property Statement
2215 The IETF takes no position regarding the validity or scope of any
2216 intellectual property or other rights that might be claimed to
2217 pertain to the implementation or use of the technology described in
2218 this document or the extent to which any license under such rights
2219 might or might not be available; neither does it represent that it
2220 has made any effort to identify any such rights. Information on the
2221 IETF's procedures with respect to rights in standards-track and
2222 standards-related documentation can be found in BCP-11. Copies of
2223 claims of rights made available for publication and any assurances of
2224 licenses to be made available, or the result of an attempt made to
2225 obtain a general license or permission for the use of such
2226 proprietary rights by implementors or users of this specification can
2227 be obtained from the IETF Secretariat.
2229 The IETF invites any interested party to bring to its attention any
2230 copyrights, patents or patent applications, or other proprietary
2231 rights which may cover technology that may be required to practice
2232 this standard. Please address the information to the IETF Executive
2233 Director.
2242 Legg Standards Track [Page 40]
2243 \f
2244 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2247 13. Author's Address
2249 Steven Legg
2250 Adacel Technologies Ltd.
2251 250 Bay Street
2252 Brighton, Victoria 3186
2253 AUSTRALIA
2255 Phone: +61 3 8530 7710
2256 Fax: +61 3 8530 7888
2257 EMail: steven.legg@adacel.com.au
2298 Legg Standards Track [Page 41]
2299 \f
2300 RFC 3687 LDAP and X.500 Component Matching Rules February 2004
2303 14. Full Copyright Statement
2305 Copyright (C) The Internet Society (2004). All Rights Reserved.
2307 This document and translations of it may be copied and furnished to
2308 others, and derivative works that comment on or otherwise explain it
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2321 The limited permissions granted above are perpetual and will not be
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2331 Acknowledgement
2333 Funding for the RFC Editor function is currently provided by the
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2354 Legg Standards Track [Page 42]
2355 \f