Network Working Group M. Nystrom
Request for Comments: 2985 B. Kaliski
Category: Informational RSA Security
November 2000
PKCS #9: Selected Object Classes and Attribute Types
Version 2.0
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract
This memo represents a republication of PKCS #9 v2.0 from RSA
Laboratories' Public-Key Cryptography Standards (PKCS) series, and
change control is retained within the PKCS process. The body of this
document, except for the security considerations section, is taken
directly from that specification.
This memo provides a selection of object classes and attribute types
for use in conjunction with public-key cryptography and Lightweight
Directory Access Protocol (LDAP) accessible directories. It also
includes ASN.1 syntax for all constructs.
Table of Contents
1. Introduction ................................................. 22. Definitions, notation and document convention ................ 22.1 Definitions ................................................. 22.2 Notation and document convention ............................ 33. Overview ..................................................... 44. Auxiliary object classes ..................................... 54.1 The "pkcsEntity" auxiliary object class ..................... 54.2 The "naturalPerson" auxiliary object class .................. 65. Selected attribute types ..................................... 65.1 Attribute types for use with the "pkcsEntity" object class .. 6
5.2 Attribute types for use with the "naturalPerson" object class 7
5.3 Attribute types for use in PKCS #7 data .................... 125.4 Attribute types for use in PKCS #10 certificate requests ... 16
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5.5 Attribute types for use in PKCS #12 "PFX" PDUs or PKCS #15
tokens ..................................................... 175.6 Attributes defined in S/MIMIE .............................. 186. Matching rules .............................................. 196.1 Case ignore match .......................................... 196.2 Signing time match ......................................... 207. Security Considerations ..................................... 208. Authors' Addresses .......................................... 21A. ASN.1 module ................................................ 22B. BNF schema summary .......................................... 30B.1 Syntaxes ................................................... 30B.2 Object classes ............................................. 31B.3 Attribute types ............................................ 32B.4 Matching rules ............................................. 36C. Intellectual property considerations ........................ 37D. Revision history ............................................ 37E. References .................................................. 39F. Contact information & About PKCS ............................ 41
Full Copyright Statement ........................................ 41
This document defines two new auxiliary object classes, pkcsEntity
and naturalPerson, and selected attribute types for use with these
classes. It also defines some attribute types for use in conjunction
with PKCS #7 [14] (and S/MIME CMS [3]) digitally signed messages,
PKCS #10 [16] certificate-signing requests, PKCS #12 [17] personal
information exchanges and PKCS #15 [18] cryptographic tokens.
Matching rules for use with these attributes are also defined,
whenever necessary.
2.1 Definitions
For the purposes of this document, the following definitions apply.
ASN.1 Abstract Syntax Notation One, as defined in [5].
Attributes An ASN.1 type that specifies a set of attributes.
Each attribute contains an attribute type (specified
by object identifier) and one or more attribute
values. Some attribute types are restricted in their
definition to have a single value; others may have
multiple values. This type is defined in [7].
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CertificationRequestInfo
An ASN.1 type that specifies a subject name, a public
key, and a set of attributes. This type is defined
in [16].
ContentInfo An ASN.1 type that specifies content exchanged
between entities. The contentType field, which has
type OBJECT IDENTIFIER, specifies the content type,
and the content field, whose type is defined by the
contentType field, contains the content value. This
type is defined in [14] and [3].
PrivateKeyInfo A type that specifies a private key and a set of
extended attributes. This type and the associated
EncryptedPrivateKeyInfo type are defined in [15].
SignerInfo A type that specifies per-signer information in the
signed-data content type, including a set of
attributes authenticated by the signer, and a set of
attributes not authenticated by the signer. This
type is defined in [14] and [3].
DER Distinguished Encoding Rules for ASN.1, as defined in
[6].
UCS Universal Multiple-Octet Coded Character Set, as
defined in [11].
UTF8String UCS Transformation Format encoded string. The UTF-8
encoding is defined in [11].
2.2 Notation and document conventions
In this document, all attribute type and object class definitions are
written in the ASN.1 value notation defined in [5]. Appendix B
contains most of these definitions written in the augmented BNF
notation defined in [2] as well. This has been done in an attempt to
simplify the task of integrating this work into LDAP [22] development
environments.
The keywords "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [1].
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This document specifies two new auxiliary object classes, pkcsEntity
and naturalPerson, and some new attribute types and matching rules.
All ASN.1 object classes, attributes, matching rules and types are
exported for use in other environments.
Attribute types defined in this document that are useful in
conjunction with storage of PKCS-related data and the pkcsEntity
object class includes PKCS #12 PFX PDUs, PKCS #15 tokens and
encrypted private keys.
Attribute types defined in this document that are useful in
conjunction with PKCS #10 certificate requests and the naturalPerson
object class includes electronic-mail address, pseudonym,
unstructured name, and unstructured address.
Attribute types defined in this document that are useful in PKCS #7
digitally signed messages are content type, message digest, signing
time, sequence number, random nonce and countersignature. The
attributes would be used in the authenticatedAttributes and
unauthenticatedAttributes fields of a SignerInfo or an
AuthenticatedData ([3]) value.
Attribute types that are useful especially in PKCS #10 certification
requests are the challenge password and the extension-request
attribute. The attributes would be used in the attributes field of a
CertificationRequestInfo value.
Note - The attributes types (from [8]) in Table 1, and probably
several others, might also be helpful in PKCS #10, PKCS #12 and PKCS
#15-aware applications.
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businessCategory preferredDeliveryMethod
commonName presentationAddress
countryName registeredAddress
description roleOccupant
destinationIndicator serialNumber
facsimileTelephoneNumber stateOrProvinceName
iSDNAddress streetAddress
localityName supportedApplicationContext
member surname
objectClass telephoneNumber
organizationName teletexTerminalIdentifier
physicalDeliveryOfficeName telexNumber
postalAddress title
postalCode x121Address
postOfficeBox
Table 1: ISO/IEC 9594-6 attribute types useful in PKCS documents
This document defines two new auxiliary object classes: pkcsEntity
and naturalPerson.
4.1 The pkcsEntity auxiliary object class
The pkcsEntity object class is a general-purpose auxiliary object
class that is intended to hold attributes about PKCS-related
entities. It has been designed for use within directory services
based on the LDAP protocol [22] and the X.500 family of protocols,
where support for PKCS-defined attributes is considered useful.
pkcsEntity OBJECT-CLASS ::= {
SUBCLASS OF { top }
KIND auxiliary
MAY CONTAIN { PKCSEntityAttributeSet }
ID pkcs-9-oc-pkcsEntity
}
PKCSEntityAttributeSet ATTRIBUTE ::= {
pKCS7PDU |
userPKCS12 |
pKCS15Token |
encryptedPrivateKeyInfo,
... -- For future extensions
}
Attributes in the PKCSEntityAttributeSet are defined in Section 5.
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4.2 The naturalPerson auxiliary object class
The naturalPerson object class is a general-purpose auxiliary object
class that is intended to hold attributes about human beings. It has
been designed for use within directory services based on the LDAP
protocol [22] and the X.500 family of protocols, where support for
these attributes is considered useful.
naturalPerson OBJECT-CLASS ::= {
SUBCLASS OF { top }
KIND auxiliary
MAY CONTAIN { NaturalPersonAttributeSet }
ID pkcs-9-oc-naturalPerson
}
NaturalPersonAttributeSet ATTRIBUTE ::= {
emailAddress |
unstructuredName |
unstructuredAddress |
dateOfBirth |
placeOfBirth |
gender |
countryOfCitizenship |
countryOfResidence |
pseudonym |
serialNumber,
... -- For future extensions
}
Attributes in the NaturalPersonAttributeSet are defined in Section 5.
5.1 Attribute types for use with the "pkcsEntity" object class
5.1.1 PKCS #7 PDU
PKCS #7 provides several formats for enveloped, signed and otherwise
protected data. When such information is stored in a directory
service, the pKCS7PDU attribute may be used.
pKCS7PDU ATTRIBUTE ::= {
WITH SYNTAX ContentInfo
ID pkcs-9-at-pkcs7PDU
}
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5.1.2 PKCS #12 token
PKCS #12 provides a format for exchange of personal identity
information. When such information is stored in a directory service,
the userPKCS12 attribute should be used.
userPKCS12 ATTRIBUTE ::= {
WITH SYNTAX PFX
ID pkcs-9-at-userPKCS12
}
This type was originally defined in [20].
5.1.3 PKCS #15 token
PKCS #15 provides a format for cryptographic tokens. When software
variants of such tokens are stored in a directory service, the
pKCS15Token attribute should be used.
pKCS15Token ATTRIBUTE ::= {
WITH SYNTAX PKCS15Token
ID pkcs-9-at-pkcs15Token
}
5.1.4 PKCS #8 encrypted private key information
PKCS #8 provides a format for encrypted private keys. When such
information is stored in a directory service, the
encryptedPrivateKeyInfo attribute should be used.
encryptedPrivateKeyInfo ATTRIBUTE ::= {
WITH SYNTAX EncryptedPrivateKeyInfo
ID pkcs-9-at-encryptedPrivateKeyInfo
}
5.2 Attribute types for use with the "naturalPerson" object class
5.2.1 Electronic-mail address
The emailAddress attribute type specifies the electronic-mail address
or addresses of a subject as an unstructured ASCII string. The
interpretation of electronic-mail addresses is intended to be
specified by certificate issuers etc.; no particular interpretation
is required.
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emailAddress ATTRIBUTE ::= {
WITH SYNTAX IA5String (SIZE(1..pkcs-9-ub-emailAddress))
EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
ID pkcs-9-at-emailAdress
}
An electronic-mail address attribute can have multiple attribute
values. When comparing two email addresses, case is irrelevant. The
pkcs9CaseIgnoreMatch is defined in Section 6.
Note - It is likely that other standards bodies overseeing
electronic-mail systems will, or have, registered electronic-mail
address attribute types specific to their system. The electronic-
mail address attribute type defined here was intended as a short-term
substitute for those specific attribute types, but is included here
for backwards-compatibility reasons.
5.2.2 Unstructured name
The unstructuredName attribute type specifies the name or names of a
subject as an unstructured ASCII string. The interpretation of
unstructured names is intended to be specified by certificate issuers
etc.; no particular interpretation is required.
unstructuredName ATTRIBUTE ::= {
WITH SYNTAX PKCS9String {pkcs-9-ub-unstructuredName}
EQUALITY MATCHING RULE pkcs9CaseIgnoreMatch
ID pkcs-9-at-unstructuredName
}
PKCS9String { INTEGER : maxSize} ::= CHOICE {
ia5String IA5String (SIZE(1..maxSize)),
directoryString DirectoryString {maxSize}
}
An unstructured-name attribute can have multiple attribute values.
When comparing two unstructured names, case is irrelevant.
The PKCS9String type is defined as a choice of IA5String and
DirectoryString. Applications SHOULD use the IA5String type when
generating attribute values in accordance with this version of this
document, unless internationalization issues makes this impossible.
In that case, the UTF8String alternative of the DirectoryString
alternative is the preferred choice. PKCS #9-attribute processing
systems MUST be able to recognize and process all string types in
PKCS9String values.
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Note - Version 1.1 of this document defined unstructuredName as
having the syntax IA5String, but did contain a note explaining that
this might be changed to a CHOICE of different string types in future
versions. To better accommodate international names, this type has
been extended to also include a directory string in this version of
this document. Since [21] does not support a directory string type
containing IA5Strings, a separate syntax object identifier has been
defined (see [21] and Appendix B).
5.2.3 Unstructured address
The unstructuredAddress attribute type specifies the address or
addresses of a subject as an unstructured directory string. The
interpretation of unstructured addresses is intended to be specified
by certificate issuers etc; no particular interpretation is required.
A likely interpretation is as an alternative to the postalAddress
attribute type defined in [8].
unstructuredAddress ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {pkcs-9-ub-unstructuredAddress}
EQUALITY MATCHING RULE caseIgnoreMatch
ID pkcs-9-at-unstructuredAddress
}
An unstructured-address attribute can have multiple attribute values.
The caseIgnoreMatch matching rule is defined in [8].
Note 1 - It is recommended to use the ASN.1 type TeletexString's
new-line character (hexadecimal code 0d) as a line separator in
multi-line addresses.
Note 2 - Previous versions of this document defined
unstructuredAddress as having the following syntax:
CHOICE {
teletexString TeletexString,
printableString PrintableString,
}
But also mentioned the possibility of a future definition as follows:
CHOICE {
teletexString TeletexString,
printableString PrintableString,
universalString UniversalString
}
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In this version of this document, the X.520 type DirectoryString has
been used in order to be more aligned with international standards
and current practice. When generating attribute values in accordance
with this version of this document, applications SHOULD use the
PrintableString alternative unless internationalization issues makes
this impossible. In those cases, the UTF8String alternative SHOULD
be used. PKCS #9-attribute processing systems MUST be able to
recognize and process all string types in DirectoryString values.
5.2.4 Date of birth
The dateOfBirth attribute specifies the date of birth for the subject
it is associated with.
dateOfBirth ATTRIBUTE ::= {
WITH SYNTAX GeneralizedTime
EQUALITY MATCHING RULE generalizedTimeMatch
SINGLE VALUE TRUE
ID pkcs-9-at-dateOfBirth
}
dateOfBirth attributes must be single-valued. The
generalizedTimeMatch matching rule is defined in [8].
5.2.5 Place of birth
The placeOfBirth attribute specifies the place of birth for the
subject it is associated with.
placeOfBirth ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {pkcs-9-ub-placeOfBirth}
EQUALITY MATCHING RULE caseExactMatch
SINGLE VALUE TRUE
ID pkcs-9-at-placeOfBirth
}
placeOfBirth attributes must be single-valued. The caseExactMatch
matching rule is defined in [8].
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5.2.6 Gender
The gender attribute specifies the gender of the subject it is
associated with.
gender ATTRIBUTE ::= {
WITH SYNTAX PrintableString (SIZE(1) ^
FROM ("M" | "F" | "m" | "f"))
EQUALITY MATCHING RULE caseIgnoreMatch
SINGLE VALUE TRUE
ID pkcs-9-at-gender
}
The letter "M" (or "m") represents "male" and the letter "F" (or "f")
represents "female". gender attributes must be single-valued.
5.2.7 Country of citizenship
The countryOfCitizenship attribute specifies the (claimed) countries
of citizenship for the subject it is associated with. It SHALL be a
2-letter acronym of a country in accordance with [4].
countryOfCitizenship ATTRIBUTE ::= {
WITH SYNTAX PrintableString (SIZE(2) ^ CONSTRAINED BY {
-- Must be a two-letter country acronym in accordance with
-- ISO/IEC 3166 --})
EQUALITY MATCHING RULE caseIgnoreMatch
ID pkcs-9-at-countryOfCitizenship
}
Attributes of this type need not be single-valued.
5.2.8 Country of residence
The countryOfResidence attribute specifies the (claimed) country of
residence for the subject is associated with. It SHALL be a 2-letter
acronym of a country in accordance with [4].
countryOfResidence ATTRIBUTE ::= {
WITH SYNTAX PrintableString (SIZE(2) ^ CONSTRAINED BY {
-- Must be a two-letter country acronym in accordance with
-- ISO/IEC 3166 --})
EQUALITY MATCHING RULE caseIgnoreMatch
ID pkcs-9-at-countryOfResidence
}
Attributes of this type need not be single-valued, since it is
possible to be a resident of several countries.
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5.2.9 Pseudonym
The pseudonym attribute type shall contain a pseudonym of a subject.
The exact interpretation of pseudonyms is intended to be specified by
certificate issuers etc.; no particular interpretation is required.
pseudonym ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {pkcs-9-ub-pseudonym}
EQUALITY MATCHING RULE caseExactMatch
ID id-at-pseudonym
}
Note - The pseudonym attribute has received an object identifier in
the joint-iso-itu-t object identifier tree.
The caseExactMatch matching rule is defined in [8].
5.2.10 Serial number
The serialNumber attribute is defined in [8].
5.3 Attribute types for use in PKCS #7 data
5.3.1 Content type
The contentType attribute type specifies the content type of the
ContentInfo value being signed in PKCS #7 (or S/MIME CMS) digitally
signed data. In such data, the contentType attribute type is
required if there are any PKCS #7 authenticated attributes.
contentType ATTRIBUTE ::= {
WITH SYNTAX ContentType
EQUALITY MATCHING RULE objectIdentifierMatch
SINGLE VALUE TRUE
ID pkcs-9-at-contentType
}
ContentType ::= OBJECT IDENTIFIER
As indicated, content-type attributes must have a single attribute
value. For two content-type values to match, their octet string
representation must be of equal length and corresponding octets
identical. The objectIdentifierMatch matching rule is defined in
[7].
Note - This attribute type is described in [3] as well.
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5.3.2 Message digest
The messageDigest attribute type specifies the message digest of the
contents octets of the DER-encoding of the content field of the
ContentInfo value being signed in PKCS #7 digitally signed data,
where the message digest is computed under the signer's message
digest algorithm. The message-digest attribute type is required in
these cases if there are any PKCS #7 authenticated attributes
present.
messageDigest ATTRIBUTE ::= {
WITH SYNTAX MessageDigest
EQUALITY MATCHING RULE octetStringMatch
SINGLE VALUE TRUE
ID pkcs-9-at-messageDigest
}
MessageDigest ::= OCTET STRING
As indicated, a message-digest attribute must have a single attribute
value. For two messageDigest values to match, their octet string
representation must be of equal length and corresponding octets
identical. The octetStringMatch matching rule is defined in [8].
Note - This attribute is described in [3] as well.
5.3.3 Signing time
The signingTime attribute type is intended for PKCS #7 digitally
signed data. It specifies the time at which the signer (purportedly)
performed the signing process.
signingTime ATTRIBUTE ::= {
WITH SYNTAX SigningTime
EQUALITY MATCHING RULE signingTimeMatch
SINGLE VALUE TRUE
ID pkcs-9-at-signingTime
}
SigningTime ::= Time -- imported from ISO/IEC 9594-8
A signing-time attribute must have a single attribute value.
The signingTimeMatch matching rule (defined in Section 6.1) returns
TRUE if an attribute value represents the same time as a presented
value.
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Quoting from [3]:
"Dates between 1 January 1950 and 31 December 2049 (inclusive) MUST
be encoded as UTCTime. Any dates with year values before 1950 or
after 2049 MUST be encoded as GeneralizedTime. [Further,] UTCTime
values MUST be expressed in Greenwich Mean Time (Zulu) and MUST
include seconds (i.e., times are YYMMDDHHMMSSZ), even where the
number of seconds is zero. Midnight (GMT) must be represented as
"YYMMDD000000Z". Century information is implicit, and the century
shall be determined as follows:
- Where YY is greater than or equal to 50, the year shall be
interpreted as 19YY; and
- Where YY is less than 50, the year shall be interpreted as 20YY.
GeneralizedTime values shall be expressed in Greenwich Mean Time
(Zulu) and must include seconds (i.e., times are YYYYMMDDHHMMSSZ),
even where the number of seconds is zero. GeneralizedTime values
must not include fractional seconds."
Note 1 - The definition of SigningTime matches the definition of Time
specified in [10].
Note 2 - No requirement is imposed concerning the correctness of the
signing time, and acceptance of a purported signing time is a matter
of a recipient's discretion. It is expected, however, that some
signers, such as time-stamp servers, will be trusted implicitly.
5.3.4 Random nonce
The randomNonce attribute type is intended for PKCS #7 digitally
signed data. It may be used by a signer unable (or unwilling) to
specify the time at which the signing process was performed. Used in
a correct manner, it will make it possible for the signer to protect
against certain attacks, i.e. replay attacks.
randomNonce ATTRIBUTE ::= {
WITH SYNTAX RandomNonce
EQUALITY MATCHING RULE octetStringMatch
SINGLE VALUE TRUE
ID pkcs-9-at-randomNonce
}
RandomNonce ::= OCTET STRING (SIZE(4..MAX))
-- At least four bytes long
A random nonce attribute must have a single attribute value.
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5.3.5 Sequence number
The sequenceNumber attribute type is intended for PKCS #7 digitally
signed data. A signer wishing to associate a sequence number to all
signature operations (much like a physical checkbook) may use it as
an alternative to the randomNonce attribute. Used in a correct
manner, it will make it possible for the signer to protect against
certain attacks, i.e. replay attacks.
sequenceNumber ATTRIBUTE ::= {
WITH SYNTAX SequenceNumber
EQUALITY MATCHING RULE integerMatch
SINGLE VALUE TRUE
ID pkcs-9-at-sequenceNumber
}
SequenceNumber ::= INTEGER (1..MAX)
A sequence number attribute must have a single attribute value.
The integerMatch matching rule is defined in [8].
5.3.6 Countersignature
The counterSignature attribute type specifies one or more signatures
on the content octets of the DER encoding of the encryptedDigest
field of a SignerInfo value in PKCS #7 digitally signed data. Thus,
the countersignature attribute type countersigns (signs in serial)
another signature. The countersignature attribute must be an
unauthenticated PKCS #7 attribute; it cannot be an authenticated
attribute.
counterSignature ATTRIBUTE ::= {
WITH SYNTAX SignerInfo
ID pkcs-9-at-counterSignature
}
Countersignature values have the same meaning as SignerInfo values
for ordinary signatures (see Section 9 of [14] and Section 5.3 of
[3]), except that:
1. The authenticatedAttributes field must contain a messageDigest
attribute if it contains any other attributes, but need not contain a
contentType attribute, as there is no content type for
countersignatures; and
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2. The input to the message-digesting process is the content octets
of the DER encoding of the signatureValue field of the SignerInfo
value with which the attribute is associated.
A countersignature attribute can have multiple attribute values.
Note 1 - The fact that a countersignature is computed on a signature
(encrypted digest) means that the countersigning process need not
know the original content input to the signing process. This has
advantages both in efficiency and in confidentiality.
Note 2 - A countersignature, since it has type SignerInfo, can itself
contain a countersignature attribute. Thus it is possible to
construct arbitrarily long series of countersignatures.
5.4 Attribute types for use with PKCS #10 certificate requests
5.4.1 Challenge password
The challengePassword attribute type specifies a password by which an
entity may request certificate revocation. The interpretation of
challenge passwords is intended to be specified by certificate
issuers etc; no particular interpretation is required.
challengePassword ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {pkcs-9-ub-challengePassword}
EQUALITY MATCHING RULE caseExactMatch
SINGLE VALUE TRUE
ID pkcs-9-at-challengePassword
}
A challenge-password attribute must have a single attribute value.
ChallengePassword attribute values generated in accordance with this
version of this document SHOULD use the PrintableString encoding
whenever possible. If internationalization issues make this
impossible, the UTF8String alternative SHOULD be used. PKCS #9-
attribute processing systems MUST be able to recognize and process
all string types in DirectoryString values.
Note - Version 1.1 of this document defined challengePassword as
having the syntax CHOICE {PrintableString, T61String}, but did
contain a note explaining that this might be changed to a CHOICE of
different string types in the future See also Note 2 in section
5.2.3.
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5.4.2 Extension request
The extensionRequest attribute type may be used to carry information
about certificate extensions the requester wishes to be included in a
certificate.
extensionRequest ATTRIBUTE ::= {
WITH SYNTAX ExtensionRequest
SINGLE VALUE TRUE
ID pkcs-9-at-extensionRequest
}
ExtensionRequest ::= Extensions
The Extensions type is imported from [10].
5.4.3 Extended-certificate attributes (deprecated)
The extendedCertificateAttributes attribute type specified a set of
attributes for a PKCS #6 [13] extended certificate in a PKCS #10
certification request (the value of the extended certificate-
attributes attribute would become the extension in the requested PKCS
#6 extended certificate). Since the status of PKCS #6 is historic
after the introduction of X.509 v3 certificates [10], the use of this
attribute is deprecated.
extendedCertificateAttributes ATTRIBUTE ::= {
WITH SYNTAX SET OF Attribute
SINGLE VALUE TRUE
ID pkcs-9-at-extendedCertificateAttributes
}
An extended certificate attributes attribute must have a single
attribute value (that value is a set, which itself may contain
multiple values, but there must be only one set).
5.5 Attributes for use in PKCS #12 "PFX" PDUs or PKCS #15 tokens
5.5.1 Friendly name
The friendlyName attribute type specifies a user-friendly name of the
object it belongs to. It is referenced in [17].
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friendlyName ATTRIBUTE ::= {
WITH SYNTAX BMPString (SIZE(1..pkcs-9-ub-friendlyName))
EQUALITY MATCHING RULE caseIgnoreMatch
SINGLE VALUE TRUE
ID pkcs-9-at-friendlyName
}
As indicated, friendlyName attributes must have a single attribute
value.
5.5.2 Local key identifier
The localKeyId attribute type specifies an identifier for a
particular key. It is only to be used locally in applications. This
attribute is referenced in [17].
localKeyId ATTRIBUTE ::= {
WITH SYNTAX OCTET STRING
EQUALITY MATCHING RULE octetStringMatch
SINGLE VALUE TRUE
ID pkcs-9-at-localKeyId
}
As indicated, localKeyId attributes must have a single attribute
value. For two localKeyId values to match, their octet string
representation must be of equal length and corresponding octets
identical.
5.6 Attributes defined in S/MIME
S/MIME (c.f. [12]) defines some attributes and object identifiers in
the PKCS #9 object identifier tree. For completeness, they are
mentioned here.
5.6.1 Signing description
The signingDescription attribute is intended to provide a short
synopsis of a message that can be used to present a user with an
additional confirmation step before committing to a cryptographic
operation. In most cases, the replication of the "Subject:" line
from the header of a message should be sufficient and is recommended.
signingDescription ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {pkcs-9-ub-signingDescription}
EQUALITY MATCHING RULE caseIgnoreMatch
SINGLE VALUE TRUE
ID pkcs-9-at-signingDescription
}
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5.6.2 S/MIME capabilities
The syntax and semantics of the smimeCapabilities attribute is
defined in [12]. It is included here for the sake of completeness.
smimeCapabilities ATTRIBUTE ::= {
WITH SYNTAX SMIMECapabilities
SINGLE VALUE
ID pkcs-9-at-smimeCapabilities
}
SMIMECapabilities ::= SEQUENCE OF SMIMECapability
SMIMECapability ::= SEQUENCE {
algorithm ALGORITHM.&id ({SMIMEv3Algorithms}),
parameters ALGORITHM.&Type ({SMIMEv3Algorithms}{@algorithm})
}
SMIMEv3Algorithms ALGORITHM ::= {... -- See RFC 2633 -- }
This section defines matching rules used in the definition of
attributes in this document.
6.1 Case ignore match
The pkcs9CaseIgnoreMatch rule compares for equality a presented
string with an attribute value of type PKCS9String, without regard to
the case (upper or lower) of the strings (e.g. "Pkcs" and "PKCS"
match).
pkcs9CaseIgnoreMatch MATCHING-RULE ::= {
SYNTAX PKCS9String {pkcs9-ub-match}
ID id-mr-pkcs9CaseIgnoreMatch
}
The rule returns TRUE if the strings are the same length and
corresponding characters are identical except possibly with regard to
case.
Where the strings being matched are of different ASN.1 syntax, the
comparison proceeds as normal so long as the corresponding characters
are in both character sets. Otherwise matching fails.
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6.2 Signing time match
The signingTimeMatch rule compares for equality a presented value
with an attribute value of type SigningTime.
signingTimeMatch MATCHING-RULE ::= {
SYNTAX SigningTime
ID pkcs-9-mr-signingTimeMatch
}
The rule returns TRUE if the attribute value represents the same time
as the presented value. If a time is specified with seconds (or
fractional seconds) absent, the number of seconds (fractional
seconds) is assumed to be zero.
Where the strings being matched are of different ASN.1 syntax, the
comparison proceeds as follows:
a) Convert both values to DER-encoded values of type GeneralizedTime,
coordinated universal time. If this is not possible the matching
fails.
b) Compare the strings for equality. The rule returns TRUE if and
only if the strings are of the same length and corresponding octets
are identical.
Attributes of directory entries are used to provide descriptive
information about the real-world objects they represent, which can be
people, organizations or devices. Most countries have privacy laws
regarding the publication of information about people.
The challengePassword attribute should not be stored un-encrypted in
a directory.
Users of directory-aware applications making use of attributes
defined for use with the pkcsEntity object class should make sure
that the class's attributes are adequately protected, since they may
potentially be read by third parties. If a password-protected value
is stored (PKCS #8, #12 or #15), the directory should authenticate
the requester before delivering the value to prevent an off-line
password-search attack. Note that this potentially raises non-
repudiation issues since the directory itself can try a password
search to recover a private value, if stored this way.
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definitions of the object class and most attribute types specified in
this document along with their associated syntaxes and matching
rules. The ABNF definitions have been done in accordance with [21],
in an attempt to ease integration with LDAP-accessible Directory
systems. Lines have been folded in some cases to improve
readability.
B.1 Syntaxes
This section defines all syntaxes that are used in this document.
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B.1.1 PKCS9String
(
1.2.840.113549.1.9.26.1
DESC 'PKCS9String'
)
The encoding of a value in this syntax is the string value itself.
B.1.2 SigningTime
(
1.2.840.113549.1.9.26.2
DESC 'SigningTime'
)
Values in this syntax are encoded as printable strings, represented
as specified in [5]. Note that the time zone must be specified. For
example, "199412161032Z".
B.2 Object classes
B.2.1 pkcsEntity
(
1.2.840.113549.1.9.24.1
NAME 'pkcsEntity'
SUP top
AUXILIARY
MAY (
pKCS7PDU $ userPKCS12 $ pKCS15Token $ encryptedPrivateKeyInfo
)
)
B.2.2 naturalPerson
(
1.2.840.113549.1.9.24.2
NAME 'naturalPerson'
SUP top
AUXILIARY
MAY (
emailAddress $ unstructuredName $ unstructuredAddress $
dateOfBirth & placeOfBirth & gender & countryOfCitizenship &
countryOfResidence & pseudonym & serialNumber
)
)
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B.3 Attribute types
B.3.1 pKCS7PDU
This attribute is to be stored and requested in binary form, as
pKCS7PDU;binary. The attribute values are BER- or DER-encoded
ContentInfo values.
(
1.2.840.113549.1.9.25.5
NAME 'pKCS7PDU'
DESC 'PKCS #7 ContentInfo PDU'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
)
B.3.2 userPKCS12
This attribute is to be stored and requested in binary form, as
userPKCS12;binary. The attribute values are PFX PDUs stored as
binary (BER- or DER-encoded) data.
(
2.16.840.1.113730.3.1.216
NAME 'userPKCS12'
DESC 'PKCS #12 PFX PDU for exchange of personal information'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
)
B.3.3 pKCS15Token
This attribute is to be stored and requested in binary form, as
pKCS15Token;binary. The attribute values are PKCS15Token PDUs stored
as binary (BER- or DER-encoded) data.
(
1.2.840.113549.1.9.25.1
NAME 'pKCS15Token'
DESC 'PKCS #15 token PDU'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
)
B.3.4 encryptedPrivateKeyInfo
This attribute is to be stored and requested in binary form, as
encryptedPrivateKeyInfo;binary. The attribute values are
EncryptedPrivateKeyInfo PDUs stored as binary (BER- or DER-encoded)
data.
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RFC 2985 Selected Object Classes and Attribute Types November 2000
(
1.2.840.113549.1.9.25.2
NAME 'encryptedPrivateKeyInfo'
DESC 'PKCS #8 encrypted private key info'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
)
B.3.5 emailAddress
(
1.2.840.113549.1.9.1
NAME 'emailAddress'
DESC 'Email address'
EQUALITY pkcs9CaseIgnoreMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.26
)
B.3.6 unstructuredName
(
1.2.840.113549.1.9.2
NAME 'unstructuredName'
DESC 'PKCS #9 unstructured name'
EQUALITY pkcs9CaseIgnoreMatch
SYNTAX 1.2.840.113549.1.9.26.1
)
B.3.7 unstructuredAddress
(
1.2.840.113549.1.9.8
NAME 'unstructuredAddress'
DESC 'PKCS #9 unstructured address'
EQUALITY caseIgnoreMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
)
B.3.8 dateOfBirth
(
1.3.6.1.5.5.7.9.1
NAME 'dateOfBirth'
DESC 'Date of birth'
EQUALITY generalizedTimeMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.24
SINGLE-VALUE
)
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B.3.9 placeOfBirth
(
1.3.6.1.5.5.7.9.2
NAME 'placeOfBirth'
DESC 'Place of birth'
EQUALITY caseExactMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
SINGLE-VALUE
)
B.3.10 gender
(
1.3.6.1.5.5.7.9.3
NAME 'gender'
DESC 'Gender'
EQUALITY caseIgnoreMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
SINGLE-VALUE
)
B.3.11 countryOfCitizenship
(
1.3.6.1.5.5.7.9.4
NAME 'countryOfCitizenship'
DESC 'Country of citizenship'
EQUALITY caseIgnoreMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
)
B.3.12 countryOfResidence
(
1.3.6.1.5.5.7.9.5
NAME 'countryOfResidence'
DESC 'Country of residence'
EQUALITY caseIgnoreMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.44
)
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B.3.13 pseudonym
(
2.5.4.65
NAME 'pseudonym'
DESC 'Pseudonym'
EQUALITY caseExactMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
)
B.3.14 contentType
In the (highly unlikely) event of this attribute being stored in a
Directory it is to be stored and requested in binary form, as
contentType;binary. Attribute values shall be OCTET STRINGs stored
as binary (BER- or DER-encoded) data.
(
1.2.840.113549.1.9.3
NAME 'contentType'
DESC 'PKCS #7 content type attribute'
EQUALITY objectIdentifierMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.38
SINGLE-VALUE
)
B.3.15 messageDigest
In the (highly unlikely) event of this attribute being stored in a
Directory it is to be stored and requested in binary form, as
messageDigest;binary. Attribute values shall be OCTET STRINGs stored
as binary (BER- or DER-encoded) data.
(
1.2.840.113549.1.9.4
NAME 'messageDigest'
DESC 'PKCS #7 mesage digest attribute'
EQUALITY octetStringMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
SINGLE-VALUE
)
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B.3.16 signingTime
(
1.2.840.113549.1.9.5
NAME 'signingTime'
DESC 'PKCS #7 signing time'
EQUALITY signingTimeMatch
SYNTAX 1.2.840.113549.1.9.26.2
SINGLE-VALUE
)
B.3.17 counterSignature
In the (highly unlikely) event that this attribute is to be stored in
a directory, it is to be stored and requested in binary form, as
counterSignature;binary. Attribute values shall be stored as binary
(BER- or DER-encoded) data.
(
1.2.840.113549.1.9.6
NAME 'counterSignature'
DESC 'PKCS #7 countersignature'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.5
)
B.3.18 challengePassword
(
1.2.840.113549.1.9.7
NAME 'challengePassword'
DESC 'Challenge password for certificate revocations'
EQUALITY caseExactMatch
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15
SINGLE-VALUE
)
Note - It is not recommended to store unprotected values of this
attribute in a directory.
B.4 Matching rules
B.4.1 pkcs9CaseIgnoreMatch
(
1.2.840.113549.1.9.27.1
NAME 'pkcs9CaseIgnoreMatch'
SYNTAX 1.2.840.113549.1.9.26.1
)
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RFC 2985 Selected Object Classes and Attribute Types November 2000
B.4.2 signingTimeMatch
(
1.2.840.113549.1.9.27.3
NAME 'signingTimeMatch'
SYNTAX 1.2.840.113549.1.9.26.2
)
RSA Security makes no patent claims on the general constructions
described in this document, although specific underlying techniques
may be covered.
License to copy this document is granted provided that it is
identified as "RSA Security Inc. Public-Key Cryptography Standards
(PKCS)" in all material mentioning or referencing this document.
RSA Security makes no representations regarding intellectual property
claims by other parties. Such determination is the responsibility of
the user.
Version 1.0
Version 1.0 was part of the June 3, 1991 initial public release of
PKCS. Version 1.0 was also published as NIST/OSI Implementors'
Workshop document SEC-SIG-91-24.
Version 1.1
Version 1.1 incorporated several editorial changes, including
updates to the references and the addition of a revision history.
The following substantive changes were made:
- Section 6: challengePassword, unstructuredAddress, and
extendedCertificateAttributes attribute types were added
- Section 7: challengePassword, unstructuredAddress, and
extendedCertificateAttributes object identifiers were added
Nystrom & Kaliski Informational [Page 37]
RFC 2985 Selected Object Classes and Attribute Types November 2000
Version 2.0
Version 2.0 incorporates several editorial changes as well. In
addition, the following substantive changes have been made:
- Addition of a Section defining two new auxiliary object classes,
pkcsEntity and naturalPerson
- Addition of several new attribute types and matching rules for
use in conjunction with these object classes and elsewhere
- Update of all ASN.1 to be in line with the 1997 version of this
syntax
- Addition a "compilable" ASN.1 module
- Addition, in accordance with [21], an ABNF description of all
attributes and object classes
- Addition of an intellectual property considerations section
Nystrom & Kaliski Informational [Page 38]
RFC 2985 Selected Object Classes and Attribute Types November 2000
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[2] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[3] Housley, R., "Cryptographic Message Syntax CMS", RFC 2630, June
1999.
[4] ISO/IEC 3166-1:Codes for the representation of names of
countries and their subdivisions - Part 1: Country codes. 1997.
[5] ISO/IEC 8824-1:1999: Information technology - Abstract Syntax
Notation One (ASN.1) - Specification of basic notation.1999.
[6] ISO/IEC 8825-1:1999: Information technology - ASN.1 Encoding
Rules: Specification of Basic Encoding Rules (BER), Canonical
Encoding Rules (CER) and Distinguished Encoding Rules (DER).
1999.
[7] ISO/IEC 9594-2:1997: Information technology - Open Systems
Interconnection - The Directory: Models. 1997.
[8] ISO/IEC 9594-6:1997: Information technology - Open Systems
Interconnection - The Directory: Selected attribute types. 1997.
[9] ISO/IEC 9594-7:1997: Information technology - Open Systems
Interconnection - The Directory: Selected object classes. 1997.
[10] ISO/IEC 9594-8:1997: Information technology - Open Systems
Interconnection - The Directory: Authentication framework. 1997.
[11] ISO/IEC 10646-1: Information Technology - Universal Multiple-
Octet Coded Character Set (UCS) - Part 1: Architecture and Basic
Multilingual Plane. 1993.
[12] Ramsdell, R., "S/MIME Version 3 Message Specification", RFC
2633, June 1999.
[13] RSA Laboratories. PKCS #6: Extended-Certificate Syntax Standard.
Version 1.5, November 1993.
[14] RSA Laboratories. PKCS #7: Cryptographic Message Syntax
Standard. Version 1.5, November 1993.
Nystrom & Kaliski Informational [Page 39]
RFC 2985 Selected Object Classes and Attribute Types November 2000
[15] RSA Laboratories. PKCS #8: Private-Key Information Syntax
Standard. Version 1.2, November 1993.
[16] RSA Laboratories. PKCS #10: Certification Request Syntax
Standard. Version 1.0, November 1993.
[17] RSA Laboratories. PKCS #12: Personal Information Exchange Syntax
Standard. Version 1.0, June 1999.
[18] RSA Laboratories. PKCS #15: Cryptographic Token Information
Format Standard. Version 1.1, June 2000.
[19] Santesson, S., Polk, W., Barzin, P. and M. Nystrom, "Internet
X.509 Public Key Infrastructure - Qualified Certificates
Profile", Work in Progress.
[20] Smith, M. "Definition of the inetOrgPerson LDAP Object Class",
RFC 2798, April 2000.
[21] Wahl, M., Coulbeck, A., Howes, T. and S. Kille, "Lightweight
Directory Access Protocol (v3): Attribute Syntax Definitions",
RFC 2252, December 1997.
[22] Wahl, M., Howes, T. and S. Kille, "Lightweight Directory Access
Protocol (v3)", RFC 2251, December 1997.
Nystrom & Kaliski Informational [Page 40]
RFC 2985 Selected Object Classes and Attribute Types November 2000
The Public-Key Cryptography Standards are specifications produced by
RSA Laboratories in cooperation with secure systems developers
worldwide for the purpose of accelerating the deployment of public-
key cryptography. First published in 1991 as a result of meetings
with a small group of early adopters of public-key technology, the
PKCS documents have become widely referenced and implemented.
Contributions from the PKCS series have become part of many formal
and de facto standards, including ANSI X9 documents, PKIX, SET,
S/MIME, and SSL.
Further development of PKCS occurs through mailing list discussions
and occasional workshops, and suggestions for improvement are
welcome. For more information, contact:
PKCS Editor
RSA Laboratories
20 Crosby Drive
Bedford, MA 01730 USA
pkcs-editor@rsasecurity.com
http://www.rsasecurity.com/rsalabs/PKCS
Nystrom & Kaliski Informational [Page 41]
RFC 2985 Selected Object Classes and Attribute Types November 2000
Full Copyright Statement
Copyright (C) The Internet Society (2000). All Rights Reserved.
This document and translations of it may be copied and furnished to
others provided that the above copyright notice and this paragraph
are included on all such copies. However, this document itself may
not be modified in any way, such as by removing the copyright notice
or references to the Internet Society or other Internet
organizations, except as required to translate it into languages
other than English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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