Network
Working Group R. Housley
Request
for Comments: 2459 SPYRUS
Category:
Standards Track W. Ford
VeriSign
W.
Polk
NIST
D. Solo
Citicorp
January
1999
Internet X.509 Public Key
Infrastructure
Certificate and CRL
Profile
Status
of this Memo
This document specifies an Internet
standards track protocol for the
Internet community, and requests discussion
and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1)
for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright
Notice
Copyright (C) The Internet Society
(1999). All Rights Reserved.
Abstract
This memo profiles the X.509 v3 certificate
and X.509 v2 CRL for use
in the Internet. An overview of the approach and model are provided
as an introduction. The X.509 v3 certificate format is described
in
detail, with additional information regarding
the format and
semantics of Internet name forms (e.g., IP
addresses). Standard
certificate extensions are described and
one new Internet-specific
extension is defined. A required set of certificate extensions is
specified.
The X.509 v2 CRL format is described and a required
extension set is defined as well. An algorithm for X.509 certificate
path validation is described. Supplemental
information is provided
describing the format of public keys and
digital signatures in X.509
certificates for common Internet public key
encryption algorithms
(i.e., RSA, DSA, and Diffie-Hellman). ASN.1 modules and examples are
provided in the appendices.
The key words "MUST", "MUST
NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT",
"RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described
in RFC 2119.
Housley,
et. al. Standards Track [Page 1]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
Please send comments on this document to
the ietf-pkix@imc.org mail
list.
TTTTaaaabbbblllleeee
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1
Introduction ................................................ 5
2
Requirements and Assumptions ................................ 6
2.1
Communication and Topology ................................ 6
2.2
Acceptability Criteria .................................... 7
2.3
User Expectations ......................................... 7
2.4
Administrator Expectations ................................ 7
3
Overview of Approach ........................................ 7
3.1
X.509 Version 3 Certificate ............................... 9
3.2
Certification Paths and Trust ............................. 10
3.3
Revocation ................................................ 12
3.4 Operational Protocols ..................................... 13
3.5
Management Protocols ...................................... 13
4
Certificate and Certificate Extensions Profile .............. 15
4.1
Basic Certificate Fields .................................. 15
4.1.1
Certificate Fields ...................................... 16
4.1.1.1
tbsCertificate ........................................ 16
4.1.1.2
signatureAlgorithm .................................... 16
4.1.1.3 signatureValue
........................................
17
4.1.2
TBSCertificate .......................................... 17
4.1.2.1
Version ............................................... 17
4.1.2.2
Serial number ......................................... 18
4.1.2.3
Signature ............................................. 18
4.1.2.4
Issuer ................................................ 18
4.1.2.5
Validity .............................................. 21
4.1.2.5.1
UTCTime ............................................. 22
4.1.2.5.2
GeneralizedTime ..................................... 22
4.1.2.6
Subject ............................................... 22
4.1.2.7
Subject Public Key Info ............................... 23
4.1.2.8
Unique Identifiers .................................... 24
4.1.2.9 Extensions
.............................................
24
4.2
Certificate Extensions .................................... 24
4.2.1
Standard Extensions ..................................... 25
4.2.1.1
Authority Key Identifier .............................. 25
4.2.1.2
Subject Key Identifier ................................ 26
4.2.1.3
Key Usage ............................................. 27
4.2.1.4
Private Key Usage Period .............................. 29
4.2.1.5
Certificate Policies .................................. 29
4.2.1.6
Policy Mappings ....................................... 31
4.2.1.7
Subject Alternative Name .............................. 32
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4.2.1.8
Issuer Alternative Name ............................... 34
4.2.1.9
Subject Directory Attributes .......................... 34
4.2.1.10
Basic Constraints .................................... 35
4.2.1.11
Name Constraints ..................................... 35
4.2.1.12
Policy Constraints ................................... 37
4.2.1.13
Extended key usage field ............................. 38
4.2.1.14
CRL Distribution Points .............................. 39
4.2.2
Private Internet Extensions ............................. 40
4.2.2.1
Authority Information Access .......................... 41
5
CRL and CRL Extensions Profile .............................. 42
5.1
CRL Fields ................................................ 43
5.1.1
CertificateList Fields .................................. 43
5.1.1.1
tbsCertList ........................................... 44
5.1.1.2
signatureAlgorithm .................................... 44
5.1.1.3
signatureValue ........................................ 44
5.1.2
Certificate List "To Be Signed" ......................... 44
5.1.2.1
Version ............................................... 45
5.1.2.2
Signature ............................................. 45
5.1.2.3
Issuer Name ........................................... 45
5.1.2.4
This Update ........................................... 45
5.1.2.5
Next Update ........................................... 45
5.1.2.6
Revoked Certificates .................................. 46
5.1.2.7
Extensions ............................................ 46
5.2
CRL Extensions ............................................ 46
5.2.1
Authority Key Identifier ................................ 47
5.2.2
Issuer Alternative Name ................................. 47
5.2.3
CRL Number .............................................. 47
5.2.4
Delta CRL Indicator ..................................... 48
5.2.5
Issuing Distribution Point .............................. 48
5.3
CRL Entry Extensions ...................................... 49
5.3.1
Reason Code ............................................. 50
5.3.2
Hold Instruction Code ................................... 50
5.3.3
Invalidity Date ......................................... 51
5.3.4
Certificate Issuer ...................................... 51
6
Certificate Path Validation ................................. 52
6.1
Basic Path Validation ..................................... 52
6.2
Extending Path Validation ................................. 56
7
Algorithm Support ........................................... 57
7.1
One-way Hash Functions .................................... 57
7.1.1
MD2 One-way Hash Function ............................... 57
7.1.2
MD5 One-way Hash Function ............................... 58
7.1.3
SHA-1 One-way Hash Function ............................. 58
7.2
Signature Algorithms ...................................... 58
7.2.1
RSA Signature Algorithm ................................. 59
7.2.2
DSA Signature Algorithm ................................. 60
7.3 Subject Public Key
Algorithms .............................
60
7.3.1
RSA Keys ................................................ 61
7.3.2
Diffie-Hellman Key Exchange Key ......................... 61
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7.3.3
DSA Signature Keys ...................................... 63
8
References .................................................. 64
9
Intellectual Property Rights ................................ 66
10
Security Considerations .................................... 67
Appendix A. ASN.1 Structures and OIDs ......................... 70
A.1 Explicitly Tagged Module, 1988 Syntax
...................... 70
A.2 Implicitly Tagged Module, 1988 Syntax
...................... 84
Appendix B. 1993 ASN.1 Structures and OIDs .................... 91
B.1 Explicitly Tagged Module, 1993 Syntax
...................... 91
B.2 Implicitly Tagged Module, 1993 Syntax
...................... 108
Appendix C. ASN.1 Notes ....................................... 116
Appendix D. Examples .......................................... 117
D.1
Certificate ............................................... 117
D.2
Certificate ............................................... 120
D.3
End-Entity Certificate Using RSA .......................... 123
D.4
Certificate Revocation List ............................... 126
Appendix E. Authors' Addresses ................................ 128
Appendix F. Full Copyright Statement .......................... 129
Housley,
et. al. Standards Track [Page 4]
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2459 Internet X.509 Public Key
Infrastructure January 1999
1 Introduction
This specification is one part of a family
of standards for the X.509
Public Key Infrastructure (PKI) for the
Internet. This specification
is a standalone document; implementations
of this standard may
proceed independent from the other parts.
This specification profiles the format and
semantics of certificates
and certificate revocation lists for the
Internet PKI. Procedures
are described for processing of
certification paths in the Internet
environment. Encoding rules are provided for popular cryptographic
algorithms. Finally, ASN.1 modules are provided in the appendices
for all data structures defined or
referenced.
The specification describes the
requirements which inspire the
creation of this document and the
assumptions which affect its scope
in Section 2. Section 3 presents an architectural model and
describes its relationship to previous IETF
and ISO/IEC/ITU
standards.
In particular, this document's relationship with the IETF
PEM specifications and the ISO/IEC/ITU
X.509 documents are described.
The specification profiles the X.509
version 3 certificate in Section
4, and the X.509 version 2 certificate
revocation list (CRL) in
Section 5. The profiles include the
identification of ISO/IEC/ITU and
ANSI extensions which may be useful in the
Internet PKI. The profiles
are presented in the 1988 Abstract Syntax
Notation One (ASN.1) rather
than the 1994 syntax used in the
ISO/IEC/ITU standards.
This specification also includes path
validation procedures in
Section 6.
These procedures are based upon the ISO/IEC/ITU
definition, but the presentation assumes
one or more self-signed
trusted CA certificates. Implementations are required to derive the
same results but are not required to use
the specified procedures.
Section 7 of the specification describes
procedures for
identification and encoding of public key
materials and digital
signatures. Implementations are not required to use any particular
cryptographic algorithms. However, conforming implementations which
use the identified algorithms are required
to identify and encode the
public key materials and digital signatures
as described.
Finally, four appendices are provided to
aid implementers. Appendix
A contains all ASN.1 structures defined or
referenced within this
specification. As above, the material is presented in the 1988
Abstract Syntax Notation One (ASN.1) rather
than the 1994 syntax.
Appendix B contains the same information in
the 1994 ASN.1 notation
as a service to implementers using updated
toolsets. However,
Appendix A takes precedence in case of
conflict. Appendix C contains
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2459 Internet X.509 Public Key
Infrastructure January 1999
notes on less familiar features of the
ASN.1 notation used within
this specification. Appendix D contains examples of a conforming
certificate and a conforming CRL.
2 Requirements and Assumptions
The goal of this specification is to
develop a profile to facilitate
the use of X.509 certificates within
Internet applications for those
communities wishing to make use of X.509
technology. Such
applications may include WWW, electronic
mail, user authentication,
and IPsec.
In order to relieve some of the obstacles to using X.509
certificates, this document defines a
profile to promote the
development of certificate management
systems; development of
application tools; and interoperability
determined by policy.
Some communities will need to supplement,
or possibly replace, this
profile in order to meet the requirements
of specialized application
domains or environments with additional
authorization, assurance, or
operational requirements. However, for basic applications, common
representations of frequently used
attributes are defined so that
application developers can obtain necessary
information without
regard to the issuer of a particular
certificate or certificate
revocation list (CRL).
A certificate user should review the
certificate policy generated by
the certification authority (CA) before
relying on the authentication
or non-repudiation services associated with
the public key in a
particular certificate. To this end, this standard does not
prescribe legally binding rules or duties.
As supplemental authorization and attribute
management tools emerge,
such as attribute certificates, it may be
appropriate to limit the
authenticated attributes that are included
in a certificate. These
other management tools may provide more
appropriate methods of
conveying many authenticated attributes.
2.1 Communication and Topology
The users of certificates will operate in a
wide range of
environments with respect to their
communication topology, especially
users of secure electronic mail. This profile supports users without
high bandwidth, real-time IP connectivity,
or high connection
availability. In addition, the profile allows for the presence of
firewall or other filtered communication.
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This profile does not assume the deployment
of an X.500 Directory
system.
The profile does not prohibit the use of an X.500 Directory,
but other means of distributing
certificates and certificate
revocation lists (CRLs) may be used.
2.2 Acceptability Criteria
The goal of the Internet Public Key
Infrastructure (PKI) is to meet
the needs of deterministic, automated
identification, authentication,
access control, and authorization
functions. Support for these
services determines the attributes
contained in the certificate as
well as the ancillary control information
in the certificate such as
policy data and certification path
constraints.
2.3 User Expectations
Users of the Internet PKI are people and
processes who use client
software and are the subjects named in
certificates. These uses
include readers and writers of electronic
mail, the clients for WWW
browsers, WWW servers, and the key manager
for IPsec within a router.
This profile recognizes the limitations of
the platforms these users
employ and the limitations in
sophistication and attentiveness of the
users themselves. This manifests itself in minimal user
configuration responsibility (e.g., trusted
CA keys, rules), explicit
platform usage constraints within the
certificate, certification path
constraints which shield the user from many
malicious actions, and
applications which sensibly automate
validation functions.
2.4 Administrator Expectations
As with user expectations, the Internet PKI
profile is structured to
support the individuals who generally
operate CAs. Providing
administrators with unbounded choices
increases the chances that a
subtle CA administrator mistake will result
in broad compromise.
Also, unbounded choices greatly complicate
the software that shall
process and validate the certificates
created by the CA.
3 Overview of Approach
Following is a simplified view of the
architectural model assumed by
the PKIX specifications.
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+---+
| C | +------------+
| e | <-------------------->| End
entity |
| r | Operational
+------------+
| t | transactions
^
|
| and management |
Management
| / | transactions |
transactions
|
|
| PKI users
| C | v
| R | -------------------+--+-----------+----------------
| L | ^ ^
|
| | | PKI management
|
| v | entities
| R | +------+ |
| e | <---------------------|
RA | <---+ |
| p |
Publish certificate
+------+ | |
| o | | |
| s | | |
| I | v v
| t | +------------+
| o |
<------------------------------|
CA |
| r |
Publish certificate
+------------+
| y |
Publish CRL
^
|
|
|
+---+ Management |
transactions |
v
+------+
| CA |
+------+
Figure 1 - PKI
Entities
The components in this model are:
end entity: user of PKI certificates and/or end user system that
is the subject of a certificate;
CA: certification authority;
RA: registration authority, i.e., an optional system to
which a CA delegates certain
management functions;
repository: a system or collection of distributed systems that
store certificates and CRLs
and serves as a means of
distributing these
certificates and CRLs to end
entities.
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3.1 X.509 Version 3 Certificate
Users of a public key shall be confident
that the associated private
key is owned by the correct remote subject
(person or system) with
which an encryption or digital signature
mechanism will be used.
This confidence is obtained through the use
of public key
certificates, which are data structures
that bind public key values
to subjects. The binding is asserted by having a trusted CA
digitally sign each certificate. The CA may
base this assertion upon
technical means (a.k.a., proof of posession
through a challenge-
response protocol), presentation of the
private key, or on an
assertion by the subject. A certificate has a limited valid lifetime
which is indicated in its signed
contents. Because a certificate's
signature and timeliness can be
independently checked by a
certificate-using client, certificates can
be distributed via
untrusted communications and server
systems, and can be cached in
unsecured storage in certificate-using
systems.
ITU-T X.509 (formerly CCITT X.509) or
ISO/IEC/ITU 9594-8, which was
first published in 1988 as part of the X.500
Directory
recommendations, defines a standard
certificate format [X.509]. The
certificate format in the 1988 standard is
called the version 1 (v1)
format.
When X.500 was revised in 1993, two more fields were added,
resulting in the version 2 (v2) format.
These two fields may be used
to support directory access control.
The Internet Privacy Enhanced Mail (PEM)
RFCs, published in 1993,
include specifications for a public key
infrastructure based on X.509
v1 certificates [RFC 1422]. The experience gained in attempts to
deploy RFC 1422 made it clear that the v1
and v2 certificate formats
are deficient in several respects. Most importantly, more fields
were needed to carry information which PEM
design and implementation
experience has proven necessary. In response to these new
requirements, ISO/IEC/ITU and ANSI X9
developed the X.509 version 3
(v3) certificate format. The v3 format extends the v2 format by
adding provision for additional extension
fields. Particular
extension field types may be specified in
standards or may be defined
and registered by any organization or
community. In June 1996,
standardization of the basic v3 format was
completed [X.509].
ISO/IEC/ITU and ANSI X9 have also developed
standard extensions for
use in the v3 extensions field
[X.509][X9.55]. These extensions can
convey such data as additional subject
identification information,
key attribute information, policy
information, and certification path
constraints.
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However, the ISO/IEC/ITU and ANSI X9
standard extensions are very
broad in their applicability. In order to develop interoperable
implementations of X.509 v3 systems for
Internet use, it is necessary
to specify a profile for use of the X.509
v3 extensions tailored for
the Internet. It is one goal of this document to specify a profile
for Internet WWW, electronic mail, and
IPsec applications.
Environments with additional requirements
may build on this profile
or may replace it.
3.2 Certification Paths and Trust
A user of a security service requiring
knowledge of a public key
generally needs to obtain and validate a
certificate containing the
required public key. If the public-key user
does not already hold an
assured copy of the public key of the CA
that signed the certificate,
the CA's name, and related information
(such as the validity period
or name constraints), then it might need an
additional certificate to
obtain that public key. In general, a chain of multiple certificates
may be needed, comprising a certificate of
the public key owner (the
end entity) signed by one CA, and zero or
more additional
certificates of CAs signed by other
CAs. Such chains, called
certification paths, are required because a
public key user is only
initialized with a limited number of
assured CA public keys.
There are different ways in which CAs might
be configured in order
for public key users to be able to find
certification paths. For
PEM, RFC 1422 defined a rigid hierarchical
structure of CAs. There
are three types of PEM certification
authority:
(a)
Internet Policy Registration Authority (IPRA): This
authority, operated under the auspices
of the Internet Society,
acts as the root of the PEM
certification hierarchy at level 1.
It issues certificates only for the next
level of authorities,
PCAs.
All certification paths start with the IPRA.
(b)
Policy Certification Authorities (PCAs): PCAs are at level 2
of the hierarchy, each PCA being
certified by the IPRA. A PCA
shall establish and publish a statement
of its policy with respect
to certifying users or subordinate
certification authorities.
Distinct PCAs aim to satisfy different
user needs. For example,
one PCA (an organizational PCA) might
support the general
electronic mail needs of commercial
organizations, and another PCA
(a high-assurance PCA) might have a more
stringent policy designed
for satisfying legally binding digital
signature requirements.
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(c)
Certification Authorities (CAs):
CAs are at level 3 of the
hierarchy and can also be at lower
levels. Those at level 3 are
certified by PCAs. CAs represent, for example, particular
organizations, particular organizational
units (e.g., departments,
groups, sections), or particular
geographical areas.
RFC 1422 furthermore has a name
subordination rule which requires
that a CA can only issue certificates for
entities whose names are
subordinate (in the X.500 naming tree) to
the name of the CA itself.
The trust associated with a PEM
certification path is implied by the
PCA name. The name subordination rule
ensures that CAs below the PCA
are sensibly constrained as to the set of
subordinate entities they
can certify (e.g., a CA for an organization
can only certify entities
in that organization's name tree).
Certificate user systems are able
to mechanically check that the name
subordination rule has been
followed.
The RFC 1422 uses the X.509 v1 certificate
formats. The limitations
of X.509 v1 required imposition of several
structural restrictions to
clearly associate policy information or
restrict the utility of
certificates. These restrictions included:
(a) a pure top-down hierarchy, with all
certification paths
starting from IPRA;
(b) a naming subordination rule
restricting the names of a CA's
subjects; and
(c) use of the PCA concept, which
requires knowledge of individual
PCAs to be built into certificate chain
verification logic.
Knowledge of individual PCAs was
required to determine if a chain
could be accepted.
With X.509 v3, most of the requirements
addressed by RFC 1422 can be
addressed using certificate extensions,
without a need to restrict
the CA structures used. In particular, the certificate extensions
relating to certificate policies obviate
the need for PCAs and the
constraint extensions obviate the need for
the name subordination
rule.
As a result, this document supports a more flexible
architecture, including:
(a) Certification paths may start with a
public key of a CA in a
user's own domain, or with the public
key of the top of a
hierarchy. Starting with the public key of a CA in a user's own
domain has certain advantages. In some environments, the local
domain is the most trusted.
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(b)
Name constraints may be imposed through explicit inclusion of
a name constraints extension in a
certificate, but are not
required.
(c)
Policy extensions and policy mappings replace the PCA
concept, which permits a greater degree
of automation. The
application can determine if the
certification path is acceptable
based on the contents of the
certificates instead of a priori
knowledge of PCAs. This permits
automation of certificate chain
processing.
3.3 Revocation
When a certificate is issued, it is
expected to be in use for its
entire validity period. However, various circumstances may cause a
certificate to become invalid prior to the
expiration of the validity
period. Such circumstances include change
of name, change of
association between subject and CA (e.g.,
an employee terminates
employment with an organization), and
compromise or suspected
compromise of the corresponding private
key. Under such
circumstances, the CA needs to revoke the
certificate.
X.509 defines one method of certificate
revocation. This method
involves each CA periodically issuing a
signed data structure called
a certificate revocation list (CRL). A CRL is a time stamped list
identifying revoked certificates which is
signed by a CA and made
freely available in a public
repository. Each revoked certificate is
identified in a CRL by its certificate
serial number. When a
certificate-using system uses a certificate
(e.g., for verifying a
remote user's digital signature), that
system not only checks the
certificate signature and validity but also
acquires a suitably-
recent CRL and checks that the certificate
serial number is not on
that CRL.
The meaning of "suitably-recent" may vary with local
policy, but it usually means the most
recently-issued CRL. A CA
issues a new CRL on a regular periodic
basis (e.g., hourly, daily, or
weekly).
An entry is added to the CRL as part of the next update
following notification of revocation. An
entry may be removed from
the CRL after appearing on one regularly
scheduled CRL issued beyond
the revoked certificate's validity period.
An advantage of this revocation method is
that CRLs may be
distributed by exactly the same means as
certificates themselves,
namely, via untrusted communications and
server systems.
One limitation of the CRL revocation
method, using untrusted
communications and servers, is that the
time granularity of
revocation is limited to the CRL issue
period. For example, if a
revocation is reported now, that revocation
will not be reliably
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2459 Internet X.509 Public Key
Infrastructure January 1999
notified to certificate-using systems until
the next periodic CRL is
issued -- this may be up to one hour, one
day, or one week depending
on the frequency that the CA issues CRLs.
As with the X.509 v3 certificate format, in
order to facilitate
interoperable implementations from multiple
vendors, the X.509 v2 CRL
format needs to be profiled for Internet
use. It is one goal of this
document to specify that profile. However, this profile does not
require CAs to issue CRLs. Message formats
and protocols supporting
on-line revocation notification may be
defined in other PKIX
specifications. On-line methods of revocation notification may be
applicable in some environments as an
alternative to the X.509 CRL.
On-line revocation checking may
significantly reduce the latency
between a revocation report and the
distribution of the information
to relying parties. Once the CA accepts the report as authentic
and
valid, any query to the on-line service
will correctly reflect the
certificate validation impacts of the
revocation. However, these
methods impose new security requirements;
the certificate validator
shall trust the on-line validation service
while the repository does
not need to be trusted.
3.4 Operational Protocols
Operational protocols are required to
deliver certificates and CRLs
(or status information) to certificate
using client systems.
Provision is needed for a variety of
different means of certificate
and CRL delivery, including distribution
procedures based on LDAP,
HTTP, FTP, and X.500. Operational protocols supporting these
functions are defined in other PKIX specifications. These
specifications may include definitions of
message formats and
procedures for supporting all of the above
operational environments,
including definitions of or references to
appropriate MIME content
types.
3.5 Management Protocols
Management protocols are required to
support on-line interactions
between PKI user and management
entities. For example, a management
protocol might be used between a CA and a
client system with which a
key pair is associated, or between two CAs
which cross-certify each
other.
The set of functions which potentially need to be supported
by management protocols include:
(a)
registration: This is the
process whereby a user first makes
itself known to a CA (directly, or
through an RA), prior to that
CA issuing a certificate or certificates for that user.
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(b)
initialization: Before a client
system can operate securely
it is necessary to install key materials
which have the
appropriate relationship with keys
stored elsewhere in the
infrastructure. For example, the client needs to be securely
initialized with the public key and
other assured information of
the trusted CA(s), to be used in
validating certificate paths.
Furthermore, a client typically needs to
be initialized with its
own key pair(s).
(c)
certification: This is the process in which a CA issues a
certificate for a user's public key, and
returns that certificate
to the user's client system and/or posts
that certificate in a
repository.
(d)
key pair recovery: As an option,
user client key materials
(e.g., a user's private key used for
encryption purposes) may be
backed up by a CA or a key backup
system. If a user needs to
recover these backed up key materials
(e.g., as a result of a
forgotten password or a lost key chain
file), an on-line protocol
exchange may be needed to support such
recovery.
(e)
key pair update: All key pairs
need to be updated regularly,
i.e., replaced with a new key pair, and
new certificates issued.
(f)
revocation request: An
authorized person advises a CA of an
abnormal situation requiring certificate
revocation.
(g)
cross-certification: Two CAs
exchange information used in
establishing a cross-certificate. A
cross-certificate is a
certificate issued by one CA to another
CA which contains a CA
signature key used for issuing
certificates.
Note that on-line protocols are not the
only way of implementing the
above functions. For all functions there are off-line methods of
achieving the same result, and this
specification does not mandate
use of on-line protocols. For example, when hardware tokens are
used, many of the functions may be achieved
as part of the physical
token delivery. Furthermore, some of the above functions may be
combined into one protocol exchange. In particular, two or more of
the registration, initialization, and
certification functions can be
combined into one protocol exchange.
The PKIX series of specifications may
define a set of standard
message formats supporting the above
functions in future
specifications. In that case, the protocols for conveying these
messages in different environments (e.g.,
on-line, file transfer, e-
mail, and WWW) will also be described in
those specifications.
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4 Certificate and Certificate Extensions
Profile
This section presents a profile for public
key certificates that will
foster interoperability and a reusable
PKI. This section is based
upon the X.509 v3 certificate format and
the standard certificate
extensions defined in [X.509]. The ISO/IEC/ITU documents use the
1993 version of ASN.1; while this document
uses the 1988 ASN.1
syntax, the encoded certificate and
standard extensions are
equivalent. This section also defines private extensions required to
support a PKI for the Internet community.
Certificates may be used in a wide range of
applications and
environments covering a broad spectrum of
interoperability goals and
a broader spectrum of operational and
assurance requirements. The
goal of this document is to establish a
common baseline for generic
applications requiring broad
interoperability and limited special
purpose requirements. In particular, the emphasis will be on
supporting the use of X.509 v3 certificates
for informal Internet
electronic mail, IPsec, and WWW
applications.
4.1 Basic Certificate Fields
The X.509 v3 certificate basic syntax is as
follows. For signature
calculation, the certificate is encoded
using the ASN.1 distinguished
encoding rules (DER) [X.208]. ASN.1 DER encoding is a tag, length,
value encoding system for each element.
Certificate ::= SEQUENCE {
tbsCertificate TBSCertificate,
signatureAlgorithm
AlgorithmIdentifier,
signatureValue BIT STRING }
TBSCertificate ::= SEQUENCE {
version [0] EXPLICIT
Version DEFAULT v1,
serialNumber CertificateSerialNumber,
signature AlgorithmIdentifier,
issuer Name,
validity Validity,
subject Name,
subjectPublicKeyInfo
SubjectPublicKeyInfo,
issuerUniqueID [1]
IMPLICIT UniqueIdentifier OPTIONAL,
-- If present,
version shall be v2 or v3
subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
-- If present,
version shall be v2 or v3
extensions [3] EXPLICIT
Extensions OPTIONAL
-- If present,
version shall be v3
}
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Version
::= INTEGER {
v1(0), v2(1), v3(2) }
CertificateSerialNumber ::=
INTEGER
Validity ::= SEQUENCE {
notBefore Time,
notAfter Time }
Time ::= CHOICE {
utcTime UTCTime,
generalTime
GeneralizedTime }
UniqueIdentifier ::= BIT STRING
SubjectPublicKeyInfo ::=
SEQUENCE {
algorithm AlgorithmIdentifier,
subjectPublicKey BIT STRING }
Extensions
::= SEQUENCE SIZE (1..MAX) OF
Extension
Extension
::= SEQUENCE {
extnID OBJECT IDENTIFIER,
critical BOOLEAN DEFAULT FALSE,
extnValue OCTET STRING }
The following items describe the X.509 v3
certificate for use in the
Internet.
4.1.1 Certificate Fields
The Certificate is a SEQUENCE of three
required fields. The fields
are described in detail in the following
subsections.
4.1.1.1 tbsCertificate
The field contains the names of the subject
and issuer, a public key
associated with the subject, a validity
period, and other associated
information. The fields are described in detail in section 4.1.2;
the tbscertificate may also include
extensions which are described in
section 4.2.
4.1.1.2 signatureAlgorithm
The signatureAlgorithm field contains the
identifier for the
cryptographic algorithm used by the CA to
sign this certificate.
Section 7.2 lists the supported signature
algorithms.
An algorithm identifier is defined by the
following ASN.1 structure:
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AlgorithmIdentifier ::=
SEQUENCE {
algorithm OBJECT IDENTIFIER,
parameters ANY DEFINED BY algorithm OPTIONAL }
The algorithm identifier is used to
identify a cryptographic
algorithm.
The OBJECT IDENTIFIER component identifies the algorithm
(such as DSA with SHA-1). The contents of the optional parameters
field will vary according to the algorithm
identified. Section 7.2
lists the supported algorithms for this
specification.
This field MUST contain the same algorithm
identifier as the
signature field in the sequence
tbsCertificate (see sec. 4.1.2.3).
4.1.1.3 signatureValue
The signatureValue field contains a digital
signature computed upon
the ASN.1 DER encoded tbsCertificate. The ASN.1 DER encoded
tbsCertificate is used as the input to the
signature function. This
signature value is then ASN.1 encoded as a
BIT STRING and included in
the Certificate's signature field. The
details of this process are
specified for each of the supported
algorithms in Section 7.2.
By generating this signature, a CA
certifies the validity of the
information in the tbsCertificate
field. In particular, the CA
certifies the binding between the public
key material and the subject
of the certificate.
4.1.2 TBSCertificate
The sequence TBSCertificate contains
information associated with the
subject of the certificate and the CA who
issued it. Every
TBSCertificate contains the names of the
subject and issuer, a public
key associated with the subject, a validity
period, a version number,
and a serial number; some may contain
optional unique identifier
fields.
The remainder of this section describes the syntax and
semantics of these fields. A TBSCertificate may also include
extensions. Extensions for the Internet PKI are described in Section
4.2.
4.1.2.1 Version
This field describes the version of the
encoded certificate. When
extensions are used, as expected in this
profile, use X.509 version 3
(value is 2). If no extensions are present, but a UniqueIdentifier
is present, use version 2 (value is
1). If only basic fields are
present, use version 1 (the value is
omitted from the certificate as
the default value).
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Implementations SHOULD be prepared to
accept any version certificate.
At a minimum, conforming implementations
MUST recognize version 3
certificates.
Generation of version 2 certificates is not
expected by
implementations based on this profile.
4.1.2.2 Serial number
The serial number is an integer assigned by
the CA to each
certificate. It MUST be unique for each certificate issued by a
given CA (i.e., the issuer name and serial
number identify a unique
certificate).
4.1.2.3 Signature
This field contains the algorithm
identifier for the algorithm used
by the CA to sign the certificate.
This field MUST contain the same algorithm
identifier as the
signatureAlgorithm field in the sequence
Certificate (see sec.
4.1.1.2).
The contents of the optional parameters field will vary
according to the algorithm identified. Section 7.2 lists the
supported signature algorithms.
4.1.2.4 Issuer
The issuer field identifies the entity who
has signed and issued the
certificate. The issuer field MUST contain a non-empty distinguished
name (DN).
The issuer field is defined as the X.501 type Name.
[X.501] Name is defined by the following
ASN.1 structures:
Name ::= CHOICE {
RDNSequence }
RDNSequence ::= SEQUENCE OF
RelativeDistinguishedName
RelativeDistinguishedName ::=
SET OF AttributeTypeAndValue
AttributeTypeAndValue ::= SEQUENCE {
type
AttributeType,
value
AttributeValue }
AttributeType ::= OBJECT IDENTIFIER
AttributeValue ::= ANY DEFINED BY
AttributeType
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DirectoryString ::= CHOICE {
teletexString TeletexString (SIZE (1..MAX)),
printableString PrintableString (SIZE (1..MAX)),
universalString UniversalString (SIZE (1..MAX)),
utf8String UTF8String (SIZE (1.. MAX)),
bmpString BMPString (SIZE (1..MAX)) }
The Name describes a hierarchical name
composed of attributes, such
as country name, and corresponding values,
such as US. The type of
the component AttributeValue is determined
by the AttributeType; in
general it will be a DirectoryString.
The DirectoryString type is defined as a
choice of PrintableString,
TeletexString, BMPString, UTF8String, and
UniversalString. The
UTF8String encoding is the preferred
encoding, and all certificates
issued after December 31, 2003 MUST use the
UTF8String encoding of
DirectoryString (except as noted
below). Until that date, conforming
CAs MUST choose from the following options
when creating a
distinguished name, including their own:
(a) if the character set is sufficient,
the string MAY be
represented as a PrintableString;
(b) failing (a), if the BMPString
character set is sufficient the
string MAY be represented as a
BMPString; and
(c) failing (a) and (b), the string MUST
be represented as a
UTF8String. If (a) or (b) is satisfied, the CA MAY still choose
to represent the string as a UTF8String.
Exceptions to the December 31, 2003 UTF8
encoding requirements are as
follows:
(a) CAs MAY issue "name
rollover" certificates to support an
orderly migration to UTF8String
encoding. Such certificates would
include the CA's UTF8String encoded name
as issuer and and the old
name encoding as subject, or vice-versa.
(b) As stated in section 4.1.2.6, the
subject field MUST be
populated with a non-empty distinguished
name matching the
contents of the issuer field in all
certificates issued by the
subject CA regardless of encoding.
The TeletexString and UniversalString are
included for backward
compatibility, and should not be used for
certificates for new
subjects.
However, these types may be used in certificates where the
name was previously established. Certificate users SHOULD be
prepared to receive certificates with these
types.
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In addition, many legacy implementations
support names encoded in the
ISO 8859-1 character set (Latin1String) but
tag them as
TeletexString. The Latin1String includes characters used in Western
European countries which are not part of
the TeletexString charcter
set.
Implementations that process TeletexString SHOULD be prepared
to handle the entire ISO 8859-1 character
set.[ISO 8859-1]
As noted above, distinguished names are
composed of attributes. This
specification does not restrict the set of
attribute types that may
appear in names. However, conforming implementations MUST be
prepared to receive certificates with
issuer names containing the set
of attribute types defined below. This specification also recommends
support for additional attribute types.
Standard sets of attributes have been
defined in the X.500 series of
specifications.[X.520] Implementations of this specification MUST
be
prepared to receive the following standard
attribute types in issuer
names: country, organization,
organizational-unit, distinguished name
qualifier, state or province name, and common name (e.g., "Susan
Housley"). In addition, implementations of this specification SHOULD
be prepared to receive the following
standard attribute types in
issuer names: locality, title, surname, given name, initials, and
generation qualifier (e.g.,
"Jr.", "3rd", or "IV"). The syntax and
associated object identifiers (OIDs) for
these attribute types are
provided in the ASN.1 modules in Appendices
A and B.
In addition, implementations of this
specification MUST be prepared
to receive the domainComponent attribute,
as defined in [RFC 2247].
The Domain (Nameserver) System (DNS)
provides a hierarchical resource
labeling system. This attribute provides is a convenient mechanism
for organizations that wish to use DNs that
parallel their DNS names.
This is not a replacement for the dNSName
component of the
alternative name field. Implementations are
not required to convert
such names into DNS names. The syntax and
associated OID for this
attribute type is provided in the ASN.1
modules in Appendices A and
B.
Certificate users MUST be prepared to
process the issuer
distinguished name and subject
distinguished name (see sec. 4.1.2.6)
fields to perform name chaining for
certification path validation
(see section 6). Name chaining is performed
by matching the issuer
distinguished name in one certificate with
the subject name in a CA
certificate.
This specification requires only a subset
of the name comparison
functionality specified in the X.500 series
of specifications. The
requirements for conforming implementations
are as follows:
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(a) attribute values encoded in
different types (e.g.,
PrintableString and BMPString) may be
assumed to represent
different strings;
(b) attribute values in types other than PrintableString are
case
sensitive (this permits matching of
attribute values as binary
objects);
(c) attribute values in PrintableString
are not case sensitive
(e.g., "Marianne Swanson" is
the same as "MARIANNE SWANSON"); and
(d) attribute values in PrintableString
are compared after
removing leading and trailing white
space and converting internal
substrings of one or more consecutive
white space characters to a
single space.
These name comparison rules permit a
certificate user to validate
certificates issued using languages or
encodings unfamiliar to the
certificate user.
In addition, implementations of this
specification MAY use these
comparison rules to process unfamiliar
attribute types for name
chaining. This allows implementations to
process certificates with
unfamiliar attributes in the issuer name.
Note that the comparison rules defined in
the X.500 series of
specifications indicate that the character
sets used to encode data
in distinguished names are irrelevant. The characters themselves are
compared without regard to encoding.
Implementations of the profile
are permitted to use the comparison
algorithm defined in the X.500
series.
Such an implementation will recognize a superset of name
matches recognized by the algorithm
specified above.
4.1.2.5 Validity
The certificate validity period is the time
interval during which the
CA warrants that it will maintain
information about the status of the
certificate. The field is represented as a
SEQUENCE of two dates:
the date on which the certificate validity
period begins (notBefore)
and the date on which the certificate
validity period ends
(notAfter). Both notBefore and notAfter may be encoded as UTCTime or
GeneralizedTime.
CAs conforming to this profile MUST always
encode certificate
validity dates through the year 2049 as
UTCTime; certificate validity
dates in 2050 or later MUST be encoded as
GeneralizedTime.
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4.1.2.5.1 UTCTime
The universal time type, UTCTime, is a
standard ASN.1 type intended
for international applications where local
time alone is not
adequate.
UTCTime specifies the year through the two low order
digits and time is specified to the
precision of one minute or one
second.
UTCTime includes either Z (for Zulu, or Greenwich Mean Time)
or a time differential.
For the purposes of this profile, UTCTime
values MUST be expressed
Greenwich Mean Time (Zulu) and MUST include
seconds (i.e., times are
YYMMDDHHMMSSZ), even where the number of
seconds is zero. Conforming
systems MUST interpret the year field (YY)
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.
4.1.2.5.2 GeneralizedTime
The generalized time type, GeneralizedTime,
is a standard ASN.1 type
for variable precision representation of
time. Optionally, the
GeneralizedTime field can include a
representation of the time
differential between local and Greenwich
Mean Time.
For the purposes of this profile,
GeneralizedTime values MUST be
expressed 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.
4.1.2.6 Subject
The subject field identifies the entity
associated with the public
key stored in the subject public key
field. The subject name may be
carried in the subject field and/or the
subjectAltName extension. If
the subject is a CA (e.g., the basic
constraints extension, as
discussed in 4.2.1.10, is present and the
value of cA is TRUE,) then
the subject field MUST be populated with a
non-empty distinguished
name matching the contents of the issuer
field (see sec. 4.1.2.4) in
all certificates issued by the subject
CA. If subject naming
information is present only in the subjectAltName
extension (e.g., a
key bound only to an email address or URI),
then the subject name
MUST be an empty sequence and the
subjectAltName extension MUST be
critical.
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Where it is non-empty, the subject field
MUST contain an X.500
distinguished name (DN). The DN MUST be
unique for each subject
entity certified by the one CA as defined
by the issuer name field. A
CA may issue more than one certificate with
the same DN to the same
subject entity.
The subject name field is defined as the
X.501 type Name.
Implementation requirements for this field
are those defined for the
issuer field (see sec. 4.1.2.4).
When encoding attribute values of
type DirectoryString, the encoding rules
for the issuer field MUST be
implemented. Implementations of this specification MUST be prepared
to receive subject names containing the
attribute types required for
the issuer field. Implementations of this specification SHOULD be
prepared to receive subject names
containing the recommended
attribute types for the issuer field. The syntax and associated
object identifiers (OIDs) for these
attribute types are provided in
the ASN.1 modules in Appendices A and
B. Implementations of this
specification MAY use these comparison
rules to process unfamiliar
attribute types (i.e., for name chaining).
This allows
implementations to process certificates
with unfamiliar attributes in
the subject name.
In addition, legacy implementations exist
where an RFC 822 name is
embedded in the subject distinguished name
as an EmailAddress
attribute.
The attribute value for EmailAddress is of type IA5String
to permit inclusion of the character '@',
which is not part of the
PrintableString character set. EmailAddress attribute values are not
case sensitive (e.g., "fanfeedback@redsox.com"
is the same as
"FANFEEDBACK@REDSOX.COM").
Conforming implementations generating new
certificates with
electronic mail addresses MUST use the
rfc822Name in the subject
alternative name field (see sec. 4.2.1.7)
to describe such
identities. Simultaneous inclusion of the EmailAddress attribute in
the subject distinguished name to support
legacy implementations is
deprecated but permitted.
4.1.2.7 Subject Public Key Info
This field is used to carry the public key
and identify the algorithm
with which the key is used. The algorithm
is identified using the
AlgorithmIdentifier structure specified in
section 4.1.1.2. The
object identifiers for the supported
algorithms and the methods for
encoding the public key materials (public
key and parameters) are
specified in section 7.3.
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4.1.2.8 Unique Identifiers
These fields may only appear if the version
is 2 or 3 (see sec.
4.1.2.1).
The subject and issuer unique identifiers are present in
the certificate to handle the possibility
of reuse of subject and/or
issuer names over time. This profile recommends that names not be
reused for different entities and that
Internet certificates not make
use of unique identifiers. CAs conforming to this profile SHOULD NOT
generate certificates with unique
identifiers. Applications
conforming to this profile SHOULD be
capable of parsing unique
identifiers and making comparisons.
4.1.2.9 Extensions
This field may only appear if the version
is 3 (see sec. 4.1.2.1).
If present, this field is a SEQUENCE of one
or more certificate
extensions. The format and content of
certificate extensions in the
Internet PKI is defined in section 4.2.
4.2 Standard Certificate Extensions
The extensions defined for X.509 v3
certificates provide methods for
associating additional attributes with
users or public keys and for
managing the certification hierarchy. The X.509 v3 certificate
format also allows communities to define
private extensions to carry
information unique to those communities. Each extension in a
certificate may be designated as critical
or non-critical. A
certificate using system MUST reject the
certificate if it encounters
a critical extension it does not recognize;
however, a non-critical
extension may be ignored if it is not
recognized. The following
sections present recommended extensions
used within Internet
certificates and standard locations for
information. Communities may
elect to use additional extensions;
however, caution should be
exercised in adopting any critical
extensions in certificates which
might prevent use in a general context.
Each extension includes an OID and an ASN.1
structure. When an
extension appears in a certificate, the OID
appears as the field
extnID and the corresponding ASN.1 encoded
structure is the value of
the octet string extnValue. Only one instance of a particular
extension may appear in a particular
certificate. For example, a
certificate may contain only one authority key
identifier extension
(see sec. 4.2.1.1). An extension includes the boolean critical,
with
a default value of FALSE. The text for each extension specifies the
acceptable values for the critical field.
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Conforming CAs MUST support key identifiers
(see sec. 4.2.1.1 and
4.2.1.2), basic constraints (see sec.
4.2.1.10), key usage (see sec.
4.2.1.3), and certificate policies (see
sec. 4.2.1.5) extensions. If
the CA issues certificates with an empty
sequence for the subject
field, the CA MUST support the subject
alternative name extension
(see sec. 4.2.1.7). Support for the remaining extensions is
OPTIONAL. Conforming CAs may support
extensions that are not
identified within this specification;
certificate issuers are
cautioned that marking such extensions as
critical may inhibit
interoperability.
At a minimum, applications conforming to
this profile MUST recognize
the extensions which must or may be
critical in this specification.
These extensions are: key usage (see sec. 4.2.1.3), certificate
policies (see sec. 4.2.1.5), the subject
alternative name (see sec.
4.2.1.7), basic constraints (see sec.
4.2.1.10), name constraints
(see sec. 4.2.1.11), policy constraints
(see sec. 4.2.1.12), and
extended key usage (see sec. 4.2.1.13).
In addition, this profile RECOMMENDS
application support for the
authority and subject key identifier (see
sec. 4.2.1.1 and 4.2.1.2)
extensions.
4.2.1 Standard Extensions
This section identifies standard
certificate extensions defined in
[X.509] for use in the Internet PKI. Each extension is associated
with an OID defined in [X.509]. These OIDs are members of the id-ce
arc, which is defined by the following:
id-ce
OBJECT IDENTIFIER ::=
{joint-iso-ccitt(2) ds(5) 29}
4.2.1.1 Authority Key Identifier
The authority key identifier extension
provides a means of
identifying the public key corresponding to
the private key used to
sign a certificate. This extension is used
where an issuer has
multiple signing keys (either due to
multiple concurrent key pairs or
due to changeover). The identification may be based on either
the
key identifier (the subject key identifier
in the issuer's
certificate) or on the issuer name and
serial number.
The keyIdentifier field of the authorityKeyIdentifier
extension MUST
be included in all certificates generated
by conforming CAs to
facilitate chain building. There is one exception; where a CA
distributes its public key in the form of a
"self-signed"
certificate, the authority key identifier
may be omitted. In this
case, the subject and authority key
identifiers would be identical.
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The value of the keyIdentifier field SHOULD
be derived from the
public key used to verify the certificate's
signature or a method
that generates unique values. Two common methods for generating key
identifiers from the public key are
described in (sec. 4.2.1.2). One
common method for generating unique values
isdescribed in (sec.
4.2.1.2).
Where a key identifier has not been previously
established, this specification recommends
use of one of these
methods for generating keyIdentifiers.
This profile recommends support for the key
identifier method by all
certificate users.
This extension MUST NOT be marked critical.
id-ce-authorityKeyIdentifier OBJECT
IDENTIFIER ::= { id-ce 35 }
AuthorityKeyIdentifier ::= SEQUENCE {
keyIdentifier [0] KeyIdentifier OPTIONAL,
authorityCertIssuer [1] GeneralNames OPTIONAL,
authorityCertSerialNumber [2]
CertificateSerialNumber OPTIONAL }
KeyIdentifier ::= OCTET STRING
4.2.1.2 Subject Key Identifier
The subject key identifier extension
provides a means of identifying
certificates that contain a particular
public key.
To facilitate chain building, this
extension MUST appear in all con-
forming CA certificates, that is, all
certificates including the
basic constraints extension (see sec.
4.2.1.10) where the value of cA
is TRUE.
The value of the subject key identifier MUST be the value
placed in the key identifier field of the
Authority Key Identifier
extension (see sec. 4.2.1.1) of
certificates issued by the subject of
this certificate.
For CA certificates, subject key
identifiers SHOULD be derived from
the public key or a method that generates
unique values. Two common
methods for generating key identifiers from
the public key are:
(1) The keyIdentifier is composed of the
160-bit SHA-1 hash of the
value of the BIT STRING subjectPublicKey
(excluding the tag,
length, and number of unused bits).
(2) The keyIdentifier is composed of a
four bit type field with
the value 0100 followed by the least
significant 60 bits of the
SHA-1 hash of the value of the BIT
STRING subjectPublicKey.
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One common method for generating unique
values is a monotomically
increasing sequence of integers.
For end entity certificates, the subject
key identifier extension
provides a means for identifying
certificates containing the
particular public key used in an
application. Where an end entity has
obtained multiple certificates, especially
from multiple CAs, the
subject key identifier provides a means to
quickly identify the set
of certificates containing a particular
public key. To assist
applications in identificiation the
appropriate end entity
certificate, this extension SHOULD be
included in all end entity
certificates.
For end entity certificates, subject key
identifiers SHOULD be
derived from the public key. Two common methods for generating key
identifiers from the public key are
identifed above.
Where a key identifier has not been
previously established, this
specification recommends use of one of
these methods for generating
keyIdentifiers.
This extension MUST NOT be marked critical.
id-ce-subjectKeyIdentifier OBJECT
IDENTIFIER ::= { id-ce 14 }
SubjectKeyIdentifier ::= KeyIdentifier
4.2.1.3 Key Usage
The key usage extension defines the purpose
(e.g., encipherment,
signature, certificate signing) of the key
contained in the
certificate. The usage restriction might be employed when a key that
could be used for more than one operation
is to be restricted. For
example, when an RSA key should be used
only for signing, the
digitalSignature and/or nonRepudiation bits
would be asserted.
Likewise, when an RSA key should be used
only for key management, the
keyEncipherment bit would be asserted. When
used, this extension
SHOULD be marked critical.
id-ce-keyUsage OBJECT IDENTIFIER
::= { id-ce 15 }
KeyUsage ::= BIT STRING {
digitalSignature (0),
nonRepudiation (1),
keyEncipherment (2),
dataEncipherment (3),
keyAgreement (4),
keyCertSign (5),
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cRLSign (6),
encipherOnly (7),
decipherOnly
(8) }
Bits in the KeyUsage type are used as
follows:
The digitalSignature bit is asserted
when the subject public key
is used with a digital signature
mechanism to support security
services other than non-repudiation (bit
1), certificate signing
(bit 5), or revocation information
signing (bit 6). Digital
signature mechanisms are often used for
entity authentication and
data origin authentication with
integrity.
The nonRepudiation bit is asserted when
the subject public key is
used to verify digital signatures used
to provide a non-
repudiation service which protects
against the signing entity
falsely denying some action, excluding
certificate or CRL signing.
The keyEncipherment bit is asserted when
the subject public key is
used for key transport. For example, when an RSA key is to be
used for key management, then this bit
shall asserted.
The dataEncipherment bit is asserted
when the subject public key
is used for enciphering user data, other
than cryptographic keys.
The keyAgreement bit is asserted when
the subject public key is
used for key agreement. For example, when a Diffie-Hellman key is
to be used for key management, then this
bit shall asserted.
The keyCertSign bit is asserted when the
subject public key is
used for verifying a signature on
certificates. This bit may only
be asserted in CA certificates.
The cRLSign bit is asserted when the subject public key is used
for verifying a signature on revocation
information (e.g., a CRL).
The meaning of the encipherOnly bit is
undefined in the absence of
the keyAgreement bit. When the encipherOnly bit is asserted and
the keyAgreement bit is also set, the
subject public key may be
used only for enciphering data while
performing key agreement.
The meaning of the decipherOnly bit is
undefined in the absence of
the keyAgreement bit.
When the decipherOnly bit is asserted and
the keyAgreement bit is also set, the
subject public key may be
used only for deciphering data while
performing key agreement.
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This profile does not restrict the
combinations of bits that may be
set in an instantiation of the keyUsage
extension. However,
appropriate values for keyUsage extensions
for particular algorithms
are specified in section 7.3.
4.2.1.4 Private Key Usage Period
This profile recommends against the use of
this extension. CAs
conforming to this profile MUST NOT generate
certificates with
critical private key usage period
extensions.
The private key usage period extension
allows the certificate issuer
to specify a different validity period for
the private key than the
certificate. This extension is intended for
use with digital
signature keys. This extension consists of two optional components,
notBefore and notAfter. The private key associated with the
certificate should not be used to sign
objects before or after the
times specified by the two components,
respectively. CAs conforming
to this profile MUST NOT generate
certificates with private key usage
period extensions unless at least one of
the two components is
present.
Where used, notBefore and notAfter are represented
as GeneralizedTime
and MUST be specified and interpreted as
defined in section
4.1.2.5.2.
id-ce-privateKeyUsagePeriod OBJECT
IDENTIFIER ::= { id-ce 16 }
PrivateKeyUsagePeriod ::= SEQUENCE {
notBefore [0] GeneralizedTime
OPTIONAL,
notAfter [1]
GeneralizedTime OPTIONAL }
4.2.1.5 Certificate Policies
The certificate policies extension contains
a sequence of one or more
policy information terms, each of which
consists of an object
identifier (OID) and optional
qualifiers. These policy information
terms indicate the policy under which the
certificate has been issued
and the purposes for which the certificate
may be used. Optional
qualifiers, which may be present, are not
expected to change the
definition of the policy.
Applications with specific policy
requirements are expected to have a
list of those policies which they will
accept and to compare the
policy OIDs in the certificate to that
list. If this extension is
critical, the path validation software MUST
be able to interpret this
extension (including the optional
qualifier), or MUST reject the
certificate.
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To promote interoperability, this profile
RECOMMENDS that policy
information terms consist of only an
OID. Where an OID alone is
insufficient, this profile strongly
recommends that use of qualifiers
be limited to those identified in this
section.
This specification defines two policy
qualifier types for use by
certificate policy writers and certificate
issuers. The qualifier
types are the CPS Pointer and User Notice
qualifiers.
The CPS Pointer qualifier contains a
pointer to a Certification
Practice Statement (CPS) published by the
CA. The pointer is in the
form of a URI.
User notice is intended for display to a
relying party when a
certificate is used. The application software SHOULD display all
user notices in all certificates of the
certification path used,
except that if a notice is duplicated only
one copy need be
displayed.
To prevent such duplication, this qualifier SHOULD only
be present in end-entity certificates and
CA certificates issued to
other organizations.
The user notice has two optional fields:
the noticeRef field and the
explicitText field.
The noticeRef field, if used, names an
organization and
identifies, by number, a particular
textual statement prepared by
that organization. For example, it might identify the
organization "CertsRUs" and
notice number 1. In a typical
implementation, the application software
will have a notice file
containing the current set of notices
for CertsRUs; the
application will extract the notice text
from the file and display
it.
Messages may be multilingual, allowing the software to select
the particular language message for its
own environment.
An explicitText field includes the
textual statement directly in
the certificate. The explicitText field is a string with a
maximum size of 200 characters.
If
both the noticeRef and explicitText options are included in the
one qualifier and if the application
software can locate the notice
text indicated by the noticeRef option then
that text should be
displayed; otherwise, the explicitText string
should be displayed.
id-ce-certificatePolicies OBJECT IDENTIFIER
::= { id-ce 32 }
certificatePolicies ::= SEQUENCE SIZE
(1..MAX) OF PolicyInformation
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PolicyInformation ::= SEQUENCE {
policyIdentifier CertPolicyId,
policyQualifiers SEQUENCE SIZE (1..MAX) OF
PolicyQualifierInfo OPTIONAL }
CertPolicyId ::= OBJECT IDENTIFIER
PolicyQualifierInfo ::= SEQUENCE {
policyQualifierId PolicyQualifierId,
qualifier ANY DEFINED BY policyQualifierId }
-- policyQualifierIds for Internet policy qualifiers
id-qt OBJECT IDENTIFIER ::=
{ id-pkix 2 }
id-qt-cps OBJECT IDENTIFIER ::=
{ id-qt 1 }
id-qt-unotice OBJECT IDENTIFIER ::= {
id-qt 2 }
PolicyQualifierId ::=
OBJECT IDENTIFIER ( id-qt-cps |
id-qt-unotice )
Qualifier ::= CHOICE {
cPSuri CPSuri,
userNotice UserNotice }
CPSuri ::= IA5String
UserNotice ::= SEQUENCE {
noticeRef NoticeReference OPTIONAL,
explicitText DisplayText OPTIONAL}
NoticeReference ::= SEQUENCE {
organization DisplayText,
noticeNumbers SEQUENCE OF INTEGER }
DisplayText ::= CHOICE {
visibleString VisibleString (SIZE (1..200)),
bmpString BMPString (SIZE
(1..200)),
utf8String UTF8String (SIZE
(1..200)) }
4.2.1.6 Policy Mappings
This extension is used in CA
certificates. It lists one or more
pairs of OIDs; each pair includes an
issuerDomainPolicy and a
subjectDomainPolicy. The pairing indicates
the issuing CA considers
its issuerDomainPolicy equivalent to the
subject CA's
subjectDomainPolicy.
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The issuing CA's users may accept an
issuerDomainPolicy for certain
applications. The policy mapping tells the
issuing CA's users which
policies associated with the subject CA are
comparable to the policy
they accept.
This extension may be supported by CAs
and/or applications, and it
MUST be non-critical.
id-ce-policyMappings OBJECT IDENTIFIER
::= { id-ce 33 }
PolicyMappings ::= SEQUENCE SIZE (1..MAX)
OF SEQUENCE {
issuerDomainPolicy CertPolicyId,
subjectDomainPolicy CertPolicyId }
4.2.1.7 Subject Alternative Name
The subject alternative names extension
allows additional identities
to be bound to the subject of the certificate. Defined options
include an Internet electronic mail
address, a DNS name, an IP
address, and a uniform resource identifier
(URI). Other options
exist, including completely local
definitions. Multiple name forms,
and multiple instances of each name form,
may be included. Whenever
such identities are to be bound into a
certificate, the subject
alternative name (or issuer alternative
name) extension MUST be used.
Because the subject alternative name is
considered to be
definitiviely bound to the public key, all parts of the subject
alternative name MUST be verified by the
CA.
Further, if the only subject identity
included in the certificate is
an alternative name form (e.g., an
electronic mail address), then the
subject distinguished name MUST be empty
(an empty sequence), and the
subjectAltName extension MUST be present.
If the subject field
contains an empty sequence, the
subjectAltName extension MUST be
marked critical.
When the subjectAltName extension contains
an Internet mail address,
the address MUST be included as an
rfc822Name. The format of an
rfc822Name is an "addr-spec" as
defined in RFC 822 [RFC 822]. An
addr-spec has the form
"local-part@domain". Note that an addr-spec
has no phrase (such as a common name)
before it, has no comment (text
surrounded in parentheses) after it, and is
not surrounded by "<" and
">". Note that while upper and
lower case letters are allowed in an
RFC 822 addr-spec, no significance is
attached to the case.
When the subjectAltName extension contains
a iPAddress, the address
MUST be stored in the octet string in
"network byte order," as
specified in RFC 791 [RFC 791]. The least
significant bit (LSB) of
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each octet is the LSB of the corresponding
byte in the network
address. For IP Version 4, as specified in
RFC 791, the octet string
MUST contain exactly four octets. For IP Version 6, as specified in
RFC 1883, the octet string MUST contain
exactly sixteen octets [RFC
1883].
When the subjectAltName extension contains
a domain name service
label, the domain name MUST be stored in
the dNSName (an IA5String).
The name MUST be in the "preferred
name syntax," as specified by RFC
1034 [RFC 1034]. Note that while upper and
lower case letters are
allowed in domain names, no signifigance is
attached to the case. In
addition, while the string " " is
a legal domain name, subjectAltName
extensions with a dNSName " " are
not permitted. Finally, the use of
the DNS representation for Internet mail
addresses (wpolk.nist.gov
instead of wpolk@nist.gov) is not
permitted; such identities are to
be encoded as rfc822Name.
When the subjectAltName extension contains
a URI, the name MUST be
stored in the uniformResourceIdentifier (an
IA5String). The name MUST
be a non-relative URL, and MUST follow the
URL syntax and encoding
rules specified in [RFC 1738]. The name must include both a scheme
(e.g., "http" or "ftp")
and a scheme-specific-part. The scheme-
specific-part must include a fully qualified
domain name or IP
address as the host.
As specified in [RFC 1738], the scheme name
is not case-sensitive
(e.g., "http" is equivalent to
"HTTP"). The host part is
also not
case-sensitive, but other components of the
scheme-specific-part may
be case-sensitive. When comparing URIs,
conforming implementations
MUST compare the scheme and host without
regard to case, but assume
the remainder of the scheme-specific-part
is case sensitive.
Subject alternative names may be constrained
in the same manner as
subject distinguished names using the name
constraints extension as
described in section 4.2.1.11.
If the subjectAltName extension is present,
the sequence MUST contain
at least one entry. Unlike the subject field, conforming CAs
MUST
NOT issue certificates with subjectAltNames
containing empty
GeneralName fields. For example, an
rfc822Name is represented as an
IA5String. While an empty string is a valid
IA5String, such an
rfc822Name is not permitted by this
profile. The behavior of clients
that encounter such a certificate when
processing a certificication
path is not defined by this profile.
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Finally, the semantics of subject
alternative names that include
wildcard characters (e.g., as a placeholder
for a set of names) are
not addressed by this specification. Applications with specific
requirements may use such names but shall
define the semantics.
id-ce-subjectAltName OBJECT IDENTIFIER
::= { id-ce 17 }
SubjectAltName ::= GeneralNames
GeneralNames ::= SEQUENCE SIZE (1..MAX)
OF GeneralName
GeneralName ::= CHOICE {
otherName [0]
OtherName,
rfc822Name [1] IA5String,
dNSName [2]
IA5String,
x400Address [3] ORAddress,
directoryName [4] Name,
ediPartyName [5] EDIPartyName,
uniformResourceIdentifier [6]
IA5String,
iPAddress [7]
OCTET STRING,
registeredID [8] OBJECT IDENTIFIER}
OtherName ::= SEQUENCE {
type-id OBJECT IDENTIFIER,
value [0] EXPLICIT ANY DEFINED BY type-id }
EDIPartyName ::= SEQUENCE {
nameAssigner [0] DirectoryString OPTIONAL,
partyName [1]
DirectoryString }
4.2.1.8 Issuer Alternative Names
As with 4.2.1.7, this extension is used to
associate Internet style
identities with the certificate issuer.
Issuer alternative names MUST
be encoded as in 4.2.1.7.
Where present, this extension SHOULD NOT be
marked critical.
id-ce-issuerAltName OBJECT IDENTIFIER
::= { id-ce 18 }
IssuerAltName ::= GeneralNames
4.2.1.9 Subject Directory Attributes
The subject directory attributes extension
is not recommended as an
essential part of this profile, but it may
be used in local
environments. This extension MUST be non-critical.
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id-ce-subjectDirectoryAttributes OBJECT
IDENTIFIER ::= { id-ce 9 }
SubjectDirectoryAttributes ::= SEQUENCE
SIZE (1..MAX) OF Attribute
4.2.1.10 Basic Constraints
The basic constraints extension identifies
whether the subject of the
certificate is a CA and how deep a
certification path may exist
through that CA.
The pathLenConstraint field is meaningful
only if cA is set to TRUE.
In this case, it gives the maximum number
of CA certificates that may
follow this certificate in a certification
path. A value of zero
indicates that only an end-entity
certificate may follow in the path.
Where it appears, the pathLenConstraint
field MUST be greater than or
equal to zero. Where pathLenConstraint does
not appear, there is no
limit to the allowed length of the
certification path.
This
extension MUST appear as a critical extension in all CA
certificates. This extension SHOULD NOT appear in end entity
certificates.
id-ce-basicConstraints OBJECT IDENTIFIER
::= { id-ce 19 }
BasicConstraints ::= SEQUENCE {
cA
BOOLEAN DEFAULT FALSE,
pathLenConstraint INTEGER (0..MAX) OPTIONAL }
4.2.1.11 Name Constraints
The name constraints extension, which MUST
be used only in a CA
certificate, indicates a name space within
which all subject names in
subsequent certificates in a certification
path shall be located.
Restrictions may apply to the subject
distinguished name or subject
alternative names. Restrictions apply only when the specified
name
form is present. If no name of the type is
in the certificate, the
certificate is acceptable.
Restrictions are defined in terms of
permitted or excluded name
subtrees.
Any name matching a restriction in the excludedSubtrees
field is invalid regardless of information
appearing in the
permittedSubtrees. This extension MUST be critical.
Within this profile, the minimum and
maximum fields are not used with
any name forms, thus minimum is always
zero, and maximum is always
absent.
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For URIs, the constraint applies to the
host part of the name. The
constraint may specify a host or a
domain. Examples would be
"foo.bar.com"; and ".xyz.com". When the the constraint begins with
a period, it may be expanded with one or
more subdomains. That is,
the constraint ".xyz.com" is
satisfied by both abc.xyz.com and
abc.def.xyz.com. However, the constraint ".xyz.com" is not satisfied
by "xyz.com". When the constraint does not begin with a
period, it
specifies a host.
A name constraint for Internat mail
addresses may specify a
particular mailbox, all addresses at a
particular host, or all
mailboxes in a domain. To indicate a particular mailbox, the
constraint is the complete mail
address. For example,
"root@xyz.com"
indicates the root mailbox on the host
"xyz.com". To indicate all
Internet mail addresses on a particular host, the constraint is
specified as the host name. For example, the constraint
"xyz.com" is
satisfied by any mail address at the host
"xyz.com". To specify any
address within a domain, the constraint is
specified with a leading
period (as with URIs). For example, ".xyz.com" indicates
all the
Internet mail addresses in the domain
"xyz.com", but Internet mail
addresses on the host "xyz.com".
DNS name restrictions are expressed as
foo.bar.com. Any subdomain
satisfies the name constraint. For example,
www.foo.bar.com would
satisfy the constraint but bigfoo.bar.com
would not.
Legacy implementations exist where an RFC
822 name is embedded in the
subject distinguished name in an attribute
of type EmailAddress (see
sec. 4.1.2.6). When rfc822 names are
constrained, but the certificate
does not include a subject alternative
name, the rfc822 name
constraint MUST be applied to the attribute
of type EmailAddress in
the
subject distinguished name. The ASN.1
syntax for EmailAddress
and the corresponding OID are supplied in
Appendix A and B.
Restrictions of the form directoryName MUST
be applied to the subject
field in the certificate and to the
subjectAltName extensions of type
directoryName. Restrictions of the form
x400Address MUST be applied
to subjectAltName extensions of type
x400Address.
When applying restrictions of the form
directoryName, an
implementation MUST compare DN attributes. At a minimum,
implementations MUST perform the DN
comparison rules specified in
Section 4.1.2.4. CAs issuing certificates with a restriction of the
form directoryName SHOULD NOT rely on
implementation of the full ISO
DN name comparison algorithm. This implies name restrictions shall
be stated identically to the encoding used
in the subject field or
subjectAltName extension.
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The syntax of iPAddress MUST be as
described in section 4.2.1.7 with
the following additions specifically for
Name Constraints. For IPv4
addresses, the ipAddress field of
generalName MUST contain eight (8)
octets, encoded in the style of RFC 1519
(CIDR) to represent an
address range.[RFC 1519] For IPv6 addresses, the ipAddress field
MUST contain 32 octets similarly
encoded. For example, a name
constraint for "class C" subnet
10.9.8.0 shall be represented as the
octets 0A 09 08 00 FF FF FF 00,
representing the CIDR notation
10.9.8.0/255.255.255.0.
The syntax and semantics for name
constraints for otherName,
ediPartyName, and registeredID are not
defined by this specification.
id-ce-nameConstraints OBJECT IDENTIFIER
::= { id-ce 30 }
NameConstraints ::= SEQUENCE {
permittedSubtrees [0]
GeneralSubtrees OPTIONAL,
excludedSubtrees [1] GeneralSubtrees OPTIONAL }
GeneralSubtrees ::= SEQUENCE SIZE
(1..MAX) OF GeneralSubtree
GeneralSubtree ::= SEQUENCE {
base GeneralName,
minimum [0]
BaseDistance DEFAULT 0,
maximum [1] BaseDistance
OPTIONAL }
BaseDistance ::= INTEGER (0..MAX)
4.2.1.12 Policy Constraints
The policy constraints extension can be
used in certificates issued
to CAs. The policy constraints extension
constrains path validation
in two ways. It can be used to prohibit
policy mapping or require
that each certificate in a path contain an
acceptable policy
identifier.
If the inhibitPolicyMapping field is
present, the value indicates the
number of additional certificates that may
appear in the path before
policy mapping is no longer permitted. For example, a value of one
indicates that policy mapping may be
processed in certificates issued
by the subject of this certificate, but not
in additional
certificates in the path.
If the requireExplicitPolicy field is
present, subsequent
certificates shall include an acceptable
policy identifier. The value
of requireExplicitPolicy indicates the
number of additional
certificates that may appear in the path
before an explicit policy is
required.
An acceptable policy identifier is the identifier of a
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policy required by the user of the
certification path or the
identifier of a policy which has been
declared equivalent through
policy mapping.
Conforming CAs MUST NOT issue certificates
where policy constraints
is a null sequence. That is, at least one
of the inhibitPolicyMapping
field or the requireExplicitPolicy field
MUST be present. The
behavior of clients that encounter a null
policy constraints field is
not addressed in this profile.
This extension may be critical or
non-critical.
id-ce-policyConstraints OBJECT IDENTIFIER
::= { id-ce 36 }
PolicyConstraints ::= SEQUENCE {
requireExplicitPolicy [0] SkipCerts OPTIONAL,
inhibitPolicyMapping [1] SkipCerts OPTIONAL }
SkipCerts ::= INTEGER (0..MAX)
4.2.1.13 Extended key usage field
This field indicates one or more purposes
for which the certified
public key may be used, in addition to or
in place of the basic
purposes indicated in the key usage
extension field. This field is
defined as follows:
id-ce-extKeyUsage OBJECT IDENTIFIER ::=
{id-ce 37}
ExtKeyUsageSyntax ::= SEQUENCE SIZE
(1..MAX) OF KeyPurposeId
KeyPurposeId ::= OBJECT IDENTIFIER
Key purposes may be defined by any
organization with a need. Object
identifiers used to identify key purposes
shall be assigned in
accordance with IANA or ITU-T Rec. X.660 |
ISO/IEC/ITU 9834-1.
This extension may, at the option of the
certificate issuer, be
either critical or non-critical.
If the extension is flagged critical, then
the certificate MUST be
used only for one of the purposes
indicated.
If the extension is flagged non-critical,
then it indicates the
intended purpose or purposes of the key,
and may be used in finding
the correct key/certificate of an entity
that has multiple
keys/certificates. It is an advisory field
and does not imply that
usage of the key is restricted by the
certification authority to the
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purpose indicated. Certificate using
applications may nevertheless
require that a particular purpose be
indicated in order for the
certificate to be acceptable to that
application.
If a certificate contains both a critical
key usage field and a
critical extended key usage field, then
both fields MUST be processed
independently and the certificate MUST only
be used for a purpose
consistent with both fields. If there is no purpose consistent with
both fields, then the certificate MUST NOT
be used for any purpose.
The following key usage purposes are defined
by this profile:
id-kp OBJECT IDENTIFIER ::= { id-pkix 3 }
id-kp-serverAuth OBJECT IDENTIFIER ::= {id-kp 1}
-- TLS Web server authentication
-- Key usage bits that may be consistent:
digitalSignature,
--
keyEncipherment or
keyAgreement
--
id-kp-clientAuth OBJECT IDENTIFIER ::= {id-kp 2}
-- TLS Web client authentication
-- Key usage bits that may be consistent:
digitalSignature and/or
-- keyAgreement
--
id-kp-codeSigning OBJECT IDENTIFIER ::= {id-kp 3}
-- Signing of downloadable executable code
-- Key usage bits that may be consistent:
digitalSignature
--
id-kp-emailProtection OBJECT IDENTIFIER ::= {id-kp 4}
-- E-mail protection
-- Key usage bits that may be consistent:
digitalSignature,
-- nonRepudiation, and/or (keyEncipherment
-- or keyAgreement)
--
id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 }
-- Binding the hash of an object to a time
from an agreed-upon time
-- source. Key usage bits that may be
consistent: digitalSignature,
-- nonRepudiation
4.2.1.14 CRL Distribution Points
The CRL distribution points extension
identifies how CRL information
is obtained. The extension SHOULD be non-critical, but this profile
recommends support for this extension by
CAs and applications.
Further discussion of CRL management is
contained in section 5.
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If the cRLDistributionPoints extension
contains a
DistributionPointName of type URI, the
following semantics MUST be
assumed: the URI is a pointer to the
current CRL for the associated
reasons and will be issued by the
associated cRLIssuer. The expected
values for the URI are those defined in
4.2.1.7. Processing rules for
other values are not defined by this
specification. If the
distributionPoint omits reasons, the CRL
MUST include revocations for
all reasons. If the distributionPoint omits
cRLIssuer, the CRL MUST
be issued by the CA that issued the
certificate.
id-ce-cRLDistributionPoints OBJECT
IDENTIFIER ::= { id-ce 31 }
cRLDistributionPoints ::= {
CRLDistPointsSyntax }
CRLDistPointsSyntax ::= SEQUENCE SIZE
(1..MAX) OF DistributionPoint
DistributionPoint ::= SEQUENCE {
distributionPoint [0]
DistributionPointName OPTIONAL,
reasons [1]
ReasonFlags OPTIONAL,
cRLIssuer [2]
GeneralNames OPTIONAL }
DistributionPointName ::= CHOICE {
fullName [0]
GeneralNames,
nameRelativeToCRLIssuer [1] RelativeDistinguishedName }
ReasonFlags ::= BIT STRING {
unused (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6) }
4.2.2 Private Internet Extensions
This section defines one new extension for
use in the Internet Public
Key Infrastructure. This extension may be used to direct
applications to identify an on-line
validation service supporting the
issuing CA. As the information may be available in multiple forms,
each extension is a sequence of IA5String
values, each of which
represents a URI. The URI implicitly specifies the location and
format of the information and the method
for obtaining the
information.
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An object identifier is defined for the
private extension. The
object identifier associated with the
private extension is defined
under the arc id-pe within the id-pkix name
space. Any future
extensions defined for the Internet PKI
will also be defined under
the arc id-pe.
id-pkix
OBJECT IDENTIFIER ::=
{ iso(1) identified-organization(3)
dod(6) internet(1)
security(5)
mechanisms(5) pkix(7) }
id-pe
OBJECT IDENTIFIER ::= { id-pkix 1 }
4.2.2.1 Authority Information Access
The authority information access extension
indicates how to access CA
information and services for the issuer of
the certificate in which
the extension appears. Information and
services may include on-line
validation services and CA policy
data. (The location of CRLs is not
specified in this extension; that
information is provided by the
cRLDistributionPoints extension.) This extension may be included in
subject or CA certificates, and it MUST be
non-critical.
id-pe-authorityInfoAccess OBJECT IDENTIFIER
::= { id-pe 1 }
AuthorityInfoAccessSyntax ::=
SEQUENCE SIZE (1..MAX) OF
AccessDescription
AccessDescription ::= SEQUENCE {
accessMethod OBJECT IDENTIFIER,
accessLocation GeneralName }
id-ad OBJECT IDENTIFIER ::= { id-pkix 48 }
id-ad-caIssuers OBJECT IDENTIFIER ::= {
id-ad 2 }
Each entry in the sequence
AuthorityInfoAccessSyntax describes the
format and location of additional
information about the CA who issued
the certificate in which this extension appears. The type and format
of the information is specified by the
accessMethod field; the
accessLocation field specifies the location
of the information. The
retrieval mechanism may be implied by the
accessMethod or specified
by accessLocation.
This profile defines one OID for
accessMethod. The id-ad-caIssuers
OID is used when the additional information
lists CAs that have
issued certificates superior to the CA that
issued the certificate
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containing this extension. The referenced CA Issuers description is
intended to aid certificate users in the
selection of a certification
path that terminates at a point trusted by
the certificate user.
When id-ad-caIssuers appears as
accessInfoType, the accessLocation
field describes the referenced description
server and the access
protocol to obtain the referenced
description. The accessLocation
field is defined as a GeneralName, which
can take several forms.
Where the information is available via
http, ftp, or ldap,
accessLocation MUST be a
uniformResourceIdentifier. Where the
information is available via the directory
access protocol (dap),
accessLocation MUST be a directoryName.
When the information is
available via electronic mail,
accessLocation MUST be an rfc822Name.
The semantics of other name forms of
accessLocation (when
accessMethod is id-ad-caIssuers) are not
defined by this
specification.
Additional access descriptors may be
defined in other PKIX
specifications.
5 CRL and CRL Extensions Profile
As described above, one goal of this X.509
v2 CRL profile is to
foster the creation of an interoperable and
reusable Internet PKI.
To achieve this goal, guidelines for the
use of extensions are
specified, and some assumptions are made
about the nature of
information included in the CRL.
CRLs may be used in a wide range of
applications and environments
covering a broad spectrum of
interoperability goals and an even
broader spectrum of operational and
assurance requirements. This
profile establishes a common baseline for
generic applications
requiring broad interoperability. The profile defines a baseline set
of information that can be expected in
every CRL. Also, the profile
defines common locations within the CRL for
frequently used
attributes as well as common
representations for these attributes.
This profile does not define any private
Internet CRL extensions or
CRL entry extensions.
Environments with additional or special
purpose requirements may
build on this profile or may replace it.
Conforming CAs are not required to issue
CRLs if other revocation or
certificate status mechanisms are
provided. Conforming CAs that
issue CRLs MUST issue version 2 CRLs, and
CAs MUST include the date
by which the next CRL will be issued in the
nextUpdate field (see
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sec. 5.1.2.5), the CRL number extension
(see sec. 5.2.3) and the
authority key identifier extension (see
sec. 5.2.1). Conforming
applications are required to process
version 1 and 2 CRLs.
5.1 CRL Fields
The X.509 v2 CRL syntax is as follows. For signature calculation,
the data that is to be signed is ASN.1 DER
encoded. ASN.1 DER
encoding is a tag, length, value encoding
system for each element.
CertificateList ::= SEQUENCE {
tbsCertList TBSCertList,
signatureAlgorithm AlgorithmIdentifier,
signatureValue BIT STRING }
TBSCertList ::= SEQUENCE {
version Version OPTIONAL,
-- if
present, shall be v2
signature AlgorithmIdentifier,
issuer Name,
thisUpdate Time,
nextUpdate Time OPTIONAL,
revokedCertificates SEQUENCE OF SEQUENCE {
userCertificate CertificateSerialNumber,
revocationDate
Time,
crlEntryExtensions Extensions OPTIONAL
--
if present, shall be v2
} OPTIONAL,
crlExtensions [0] EXPLICIT Extensions OPTIONAL
--
if present, shall be v2
}
-- Version, Time, CertificateSerialNumber,
and Extensions
-- are all defined in the ASN.1 in section
4.1
-- AlgorithmIdentifier is defined in
section 4.1.1.2
The following items describe the use of the
X.509 v2 CRL in the
Internet PKI.
5.1.1 CertificateList Fields
The CertificateList is a SEQUENCE of three
required fields. The
fields are described in detail in the
following subsections.
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5.1.1.1 tbsCertList
The first field in the sequence is the
tbsCertList. This field is
itself a sequence containing the name of
the issuer, issue date,
issue date of the next list, the list of
revoked certificates, and
optional CRL extensions. Further, each entry on the revoked
certificate list is defined by a sequence
of user certificate serial
number, revocation date, and optional CRL
entry extensions.
5.1.1.2 signatureAlgorithm
The signatureAlgorithm field contains the
algorithm identifier for
the algorithm used by the CA to sign the
CertificateList. The field
is of type AlgorithmIdentifier, which is
defined in section 4.1.1.2.
Section 7.2 lists the supported algorithms
for this specification.
Conforming CAs MUST use the algorithm
identifiers presented in
section 7.2 when signing with a supported
signature algorithm.
This field MUST contain the same algorithm
identifier as the
signature field in the sequence tbsCertList
(see sec. 5.1.2.2).
5.1.1.3 signatureValue
The signatureValue field contains a digital
signature computed upon
the ASN.1 DER encoded tbsCertList. The ASN.1 DER encoded tbsCertList
is used as the input to the signature
function. This signature value
is then ASN.1 encoded as a BIT STRING and included
in the CRL's
signatureValue field. The details of this
process are specified for
each of the supported algorithms in section
7.2.
5.1.2 Certificate List "To Be Signed"
The certificate list to be signed, or
TBSCertList, is a SEQUENCE of
required and optional fields. The required fields identify the CRL
issuer, the algorithm used to sign the CRL,
the date and time the CRL
was issued, and the date and time by which
the CA will issue the next
CRL.
Optional fields include lists of revoked
certificates and CRL
extensions. The revoked certificate list is optional to support the
case where a CA has not revoked any
unexpired certificates that it
has issued. The profile requires conforming CAs to use the CRL
extension cRLNumber in all CRLs issued.
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5.1.2.1 Version
This optional field describes the version
of the encoded CRL. When
extensions are used, as required by this
profile, this field MUST be
present and MUST specify version 2 (the
integer value is 1).
5.1.2.2 Signature
This field contains the algorithm identifier
for the algorithm used
to sign the CRL. Section 7.2 lists OIDs for the most popular
signature algorithms used in the Internet
PKI.
This field MUST contain the same algorithm
identifier as the
signatureAlgorithm field in the sequence
CertificateList (see section
5.1.1.2).
5.1.2.3 Issuer Name
The issuer name identifies the entity who
has signed and issued the
CRL.
The issuer identity is carried in the issuer name field.
Alternative name forms may also appear in
the issuerAltName extension
(see sec. 5.2.2). The issuer name field MUST contain an X.500
distinguished name (DN). The issuer name field is defined as the
X.501 type Name, and MUST follow the
encoding rules for the issuer
name field in the certificate (see sec.
4.1.2.4).
5.1.2.4 This Update
This field indicates the issue date of this
CRL. ThisUpdate may be
encoded as UTCTime or GeneralizedTime.
CAs conforming to this profile that issue
CRLs MUST encode thisUpdate
as
UTCTime for dates through the year 2049. CAs conforming to this
profile that issue CRLs MUST encode
thisUpdate as GeneralizedTime for
dates in the year 2050 or later.
Where encoded as UTCTime, thisUpdate MUST
be specified and
interpreted as defined in section
4.1.2.5.1. Where encoded as
GeneralizedTime, thisUpdate MUST be
specified and interpreted as
defined in section 4.1.2.5.2.
5.1.2.5 Next Update
This field indicates the date by which the
next CRL will be issued.
The next CRL could be issued before the
indicated date, but it will
not be issued any later than the indicated
date. CAs SHOULD issue
CRLs with a nextUpdate time equal to or
later than all previous CRLs.
nextUpdate may be encoded as UTCTime or
GeneralizedTime.
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This profile requires inclusion of
nextUpdate in all CRLs issued by
conforming CAs. Note that the ASN.1 syntax
of TBSCertList describes
this field as OPTIONAL, which is consistent
with the ASN.1 structure
defined in [X.509]. The behavior of clients
processing CRLs which
omit nextUpdate is not specified by this
profile.
CAs conforming to this profile that issue
CRLs MUST encode nextUpdate
as UTCTime for dates through the year 2049.
CAs conforming to this
profile that issue CRLs MUST encode
nextUpdate as GeneralizedTime for
dates in the year 2050 or later.
Where encoded as UTCTime, nextUpdate MUST
be specified and
interpreted as defined in section
4.1.2.5.1. Where encoded as
GeneralizedTime, nextUpdate MUST be
specified and interpreted as
defined in section 4.1.2.5.2.
5.1.2.6 Revoked Certificates
Revoked certificates are listed. The revoked certificates are named
by their serial numbers. Certificates revoked by the CA are uniquely
identified by the certificate serial
number. The date on which the
revocation occurred is specified. The time for revocationDate MUST
be expressed as described in section
5.1.2.4. Additional information
may be supplied in CRL entry extensions;
CRL entry extensions are
discussed in section 5.3.
5.1.2.7 Extensions
This field may only appear if the version
is 2 (see sec. 5.1.2.1).
If present, this field is a SEQUENCE of one
or more CRL extensions.
CRL extensions are discussed in section
5.2.
5.2 CRL Extensions
The extensions defined by ANSI X9 and
ISO/IEC/ITU for X.509 v2 CRLs
[X.509] [X9.55] provide methods for
associating additional attributes
with CRLs.
The X.509 v2 CRL format also allows communities to define
private extensions to carry information
unique to those communities.
Each extension in a CRL may be designated
as critical or non-
critical.
A CRL validation MUST fail if it encounters a critical
extension which it does not know how to
process. However, an
unrecognized non-critical extension may be
ignored. The following
subsections present those extensions used
within Internet CRLs.
Communities may elect to include extensions
in CRLs which are not
defined in this specification. However,
caution should be exercised
in adopting any critical extensions in CRLs
which might be used in a
general context.
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Conforming CAs that issue CRLs are required
to include the authority
key identifier (see sec. 5.2.1) and the CRL
number (see sec. 5.2.3)
extensions in all CRLs issued.
5.2.1 Authority Key Identifier
The authority key identifier extension
provides a means of
identifying the public key corresponding to
the private key used to
sign a CRL. The identification can be based on either the key
identifier (the subject key identifier in
the CRL signer's
certificate) or on the issuer name and
serial number. This extension
is especially useful where an issuer has
more than one signing key,
either due to multiple concurrent key pairs
or due to changeover.
Conforming CAs MUST use the key identifier
method, and MUST include
this extension in all CRLs issued.
The syntax for this CRL extension is
defined in section 4.2.1.1.
5.2.2 Issuer Alternative Name
The issuer alternative names extension
allows additional identities
to be associated with the issuer of the
CRL. Defined options include
an rfc822 name (electronic mail address), a
DNS name, an IP address,
and a URI.
Multiple instances of a name and multiple name forms may
be included. Whenever such identities are used, the issuer
alternative name extension MUST be used.
The issuerAltName extension SHOULD NOT be
marked critical.
The OID and syntax for this CRL extension
are defined in section
4.2.1.8.
5.2.3 CRL Number
The CRL number is a non-critical CRL
extension which conveys a
monotonically increasing sequence number
for each CRL issued by a CA.
This extension allows users to easily
determine when a particular CRL
supersedes another CRL. CAs conforming to this profile MUST include
this extension in all CRLs.
id-ce-cRLNumber OBJECT IDENTIFIER ::= {
id-ce 20 }
cRLNumber ::= INTEGER (0..MAX)
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5.2.4 Delta CRL Indicator
The delta CRL indicator is a critical CRL
extension that identifies a
delta-CRL.
The use of delta-CRLs can significantly improve
processing time for applications which
store revocation information
in a format other than the CRL
structure. This allows changes to be
added to the local database while ignoring
unchanged information that
is already in the local database.
When a delta-CRL is issued, the CAs MUST
also issue a complete CRL.
The value of BaseCRLNumber identifies the
CRL number of the base CRL
that was used as the starting point in the
generation of this delta-
CRL.
The delta-CRL contains the changes between the base CRL and the
current CRL issued along with the delta-CRL. It is the decision of a
CA as to whether to provide
delta-CRLs. Again, a delta-CRL MUST NOT
be issued without a corresponding complete
CRL. The value of
CRLNumber for both the delta-CRL and the
corresponding complete CRL
MUST be identical.
A CRL user constructing a locally held CRL
from delta-CRLs MUST
consider the constructed CRL incomplete and
unusable if the CRLNumber
of the received delta-CRL is more than one
greater than the CRLnumber
of the delta-CRL last processed.
id-ce-deltaCRLIndicator OBJECT IDENTIFIER
::= { id-ce 27 }
deltaCRLIndicator ::= BaseCRLNumber
BaseCRLNumber ::= CRLNumber
5.2.5 Issuing Distribution Point
The issuing distribution point is a
critical CRL extension that
identifies the CRL distribution point for a
particular CRL, and it
indicates whether the CRL covers revocation
for end entity
certificates only, CA certificates only, or a limitied set of
reason
codes.
Although the extension is critical, conforming
implementations are not required to support
this extension.
The CRL is signed using the CA's private
key. CRL Distribution
Points do not have their own key
pairs. If the CRL is stored in the
X.500 Directory, it is stored in the Directory
entry corresponding to
the CRL distribution point, which may be
different than the Directory
entry of the CA.
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The reason codes associated with a
distribution point shall be
specified in onlySomeReasons. If
onlySomeReasons does not appear, the
distribution point shall contain
revocations for all reason codes.
CAs may use CRL distribution points to
partition the CRL on the basis
of compromise and routine revocation. In this case, the revocations
with reason code keyCompromise (1) and
cACompromise (2) appear in one
distribution point, and the revocations
with other reason codes
appear in another distribution point.
Where the issuingDistributionPoint
extension contains a URL, the
following semantics MUST be assumed: the
object is a pointer to the
most current CRL issued by this CA. The URI schemes ftp, http,
mailto [RFC1738] and ldap [RFC1778] are
defined for this purpose.
The URI MUST be an absolute, not relative,
pathname and MUST specify
the host.
id-ce-issuingDistributionPoint OBJECT
IDENTIFIER ::= { id-ce 28 }
issuingDistributionPoint ::= SEQUENCE {
distributionPoint [0] DistributionPointName OPTIONAL,
onlyContainsUserCerts [1] BOOLEAN DEFAULT FALSE,
onlyContainsCACerts [2] BOOLEAN DEFAULT FALSE,
onlySomeReasons [3] ReasonFlags OPTIONAL,
indirectCRL [4] BOOLEAN DEFAULT FALSE }
5.3 CRL Entry Extensions
The CRL entry extensions already defined by
ANSI X9 and ISO/IEC/ITU
for X.509 v2 CRLs provide methods for
associating additional
attributes with CRL entries [X.509]
[X9.55]. The X.509 v2 CRL format
also allows communities to define private
CRL entry extensions to
carry information unique to those
communities. Each extension in a
CRL entry may be designated as critical or
non-critical. A CRL
validation MUST fail if it encounters a
critical CRL entry extension
which it does not know how to process. However, an unrecognized
non-critical CRL entry extension may be
ignored. The following
subsections present recommended extensions
used within Internet CRL
entries and standard locations for
information. Communities may
elect to use additional CRL entry
extensions; however, caution should
be exercised in adopting any critical
extensions in CRL entries which
might be used in a general context.
All CRL entry extensions used in this
specification are non-critical.
Support for these extensions is optional
for conforming CAs and
applications. However, CAs that issue CRLs SHOULD include reason
codes (see sec. 5.3.1) and invalidity dates
(see sec. 5.3.3) whenever
this information is available.
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5.3.1 Reason Code
The reasonCode is a non-critical CRL entry
extension that identifies
the reason for the certificate revocation.
CAs are strongly
encouraged to include meaningful reason
codes in CRL entries;
however, the reason code CRL entry
extension SHOULD be absent instead
of using the unspecified (0) reasonCode
value.
id-ce-cRLReason OBJECT IDENTIFIER ::= {
id-ce 21 }
-- reasonCode ::= { CRLReason }
CRLReason ::= ENUMERATED {
unspecified (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6),
removeFromCRL (8) }
5.3.2 Hold Instruction Code
The hold instruction code is a non-critical
CRL entry extension that
provides a registered instruction
identifier which indicates the
action to be taken after encountering a
certificate that has been
placed on hold.
id-ce-holdInstructionCode OBJECT IDENTIFIER
::= { id-ce 23 }
holdInstructionCode ::= OBJECT IDENTIFIER
The following instruction codes have been
defined. Conforming
applications that process this extension
MUST recognize the following
instruction codes.
holdInstruction OBJECT IDENTIFIER ::=
{ iso(1) member-body(2)
us(840) x9-57(10040) 2 }
id-holdinstruction-none OBJECT IDENTIFIER ::= {holdInstruction 1}
id-holdinstruction-callissuer
OBJECT IDENTIFIER
::= {holdInstruction 2}
id-holdinstruction-reject OBJECT IDENTIFIER
::= {holdInstruction 3}
Conforming applications which encounter an
id-holdinstruction-
callissuer MUST call the certificate issuer
or reject the
certificate. Conforming applications which encounter an id-
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holdinstruction-reject MUST reject the
certificate. The hold
instruction id-holdinstruction-none is
semantically equivalent to the
absence of a holdInstructionCode, and its
use is strongly deprecated
for the Internet PKI.
5.3.3 Invalidity Date
The invalidity date is a non-critical CRL
entry extension that
provides the date on which it is known or
suspected that the private
key was compromised or that the certificate
otherwise became invalid.
This date may be earlier than the
revocation date in the CRL entry,
which is the date at which the CA processed
the revocation. When a
revocation is first posted by a CA in a
CRL, the invalidity date may
precede the date of issue of earlier CRLs,
but the revocation date
SHOULD NOT precede the date of issue of
earlier CRLs. Whenever this
information is available, CAs are strongly
encouraged to share it
with CRL users.
The GeneralizedTime values included in this
field MUST be expressed
in Greenwich Mean Time (Zulu), and MUST be
specified and interpreted
as defined in section 4.1.2.5.2.
id-ce-invalidityDate OBJECT IDENTIFIER ::=
{ id-ce 24 }
invalidityDate ::= GeneralizedTime
5.3.4 Certificate Issuer
This CRL entry extension identifies the
certificate issuer associated
with an entry in an indirect CRL, i.e. a
CRL that has the indirectCRL
indicator set in its issuing distribution
point extension. If this
extension is not present on the first entry
in an indirect CRL, the
certificate issuer defaults to the CRL
issuer. On subsequent entries
in an indirect CRL, if this extension is
not present, the certificate
issuer for the entry is the same as that
for the preceding entry.
This field is defined as follows:
id-ce-certificateIssuer OBJECT IDENTIFIER ::= { id-ce 29 }
certificateIssuer ::= GeneralNames
If used by conforming CAs that issue CRLs,
this extension is always
critical.
If an implementation ignored this extension it could not
correctly attribute CRL entries to
certificates. This specification
RECOMMENDS that implementations recognize
this extension.
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6 Certification Path Validation
Certification path validation procedures
for the Internet PKI are
based on section 12.4.3 of [X.509]. Certification path processing
verifies the binding between the subject
distinguished name and/or
subject alternative name and subject public
key. The binding is
limited by constraints which are specified
in the certificates which
comprise the path. The basic constraints
and policy constraints
extensions allow the certification path
processing logic to automate
the decision making process.
This section describes an algorithm for
validating certification
paths.
Conforming implementations of this specification are not
required to implement this algorithm, but
MUST be functionally
equivalent to the external behavior
resulting from this procedure.
Any algorithm may be used by a particular
implementation so long as
it derives the correct result.
In section 6.1, the text describes basic
path validation. This text
assumes that all valid paths begin with
certificates issued by a
single "most-trusted CA". The
algorithm requires the public key of
the CA, the CA's name, the validity period
of the public key, and any
constraints upon the set of paths which may
be validated using this
key.
The "most-trusted CA" is a matter
of policy: it could be a root CA in
a hierarchical PKI; the CA that issued the
verifier's own
certificate(s); or any other CA in a
network PKI. The path
validation procedure is the same regardless
of the choice of "most-
trusted CA."
section 6.2 describes extensions to the
basic path validation
algorithm. Two specific cases are
discussed: the case where paths may
begin with one of several trusted CAs; and
where compatibility with
the PEM architecture is required.
6.1
Basic Path Validation
The text assumes that the trusted public
key (and related
information) is contained in a
"self-signed" certificate. This
simplifies the description of the path
processing procedure. Note
that the signature on the self-signed
certificate does not provide
any security services. The trusted public key (and related
information) may be obtained in other
formats; the information is
trusted because of other procedures used to
obtain and protect it.
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The goal of path validation is to verify
the binding between a
subject distinguished name or subject
alternative name and subject
public key, as represented in the "end
entity" certificate, based on
the public key of the "most-trusted
CA". This requires obtaining a
sequence of certificates that support that
binding. The procedures
performed to obtain this sequence is
outside the scope of this
section.
The following text also assumes that
certificates do not use subject
or unique identifier fields or private
critical extensions, as
recommended within this profile. However, if these components appear
in certificates, they MUST be
processed. Finally, policy qualifiers
are also neglected for the sake of clarity.
A certification path is a sequence of n
certificates where:
* for all x in {1,(n-1)}, the subject of
certificate x is the
issuer of certificate x+1.
* certificate x=1 is the the self-signed
certificate, and
* certificate x=n is the end entity
certificate.
This section assumes the following inputs
are provided to the path
processing logic:
(a)
a certification path of length n;
(b)
a set of initial policy identifiers (each comprising a
sequence of policy element identifiers),
which identifies one or
more certificate policies, any one of
which would be acceptable
for the purposes of certification path processing,
or the special
value "any-policy";
(c)
the current date/time (if not available internally to the
certification path processing module);
and
(d)
the time, T, for which the validity of the path should be
determined. (This may be the current date/time, or some point in
the past.)
From the inputs, the procedure intializes
five state variables:
(a)
acceptable policy set: A set of
certificate policy
identifiers comprising the policy or
policies recognized by the
public key user together with policies
deemed equivalent through
policy mapping. The initial value of the
acceptable policy set is
the special value
"any-policy".
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(b)
constrained subtrees: A set of
root names defining a set of
subtrees within which all subject names
in subsequent certificates
in the certification path shall fall.
The initial value is
"unbounded".
(c)
excluded subtrees: A set of root
names defining a set of
subtrees within which no subject name in
subsequent certificates
in the certification path may fall. The
initial value is "empty".
(d)
explicit policy: an integer which indicates if an explicit
policy identifier is required. The
integer indicates the first
certificate in the path where this
requirement is imposed. Once
set, this variable may be decreased, but
may not be increased.
(That is, if a certificate in the path
requires explicit policy
identifiers, a later certificate can not
remove this requirement.)
The initial value is n+1.
(e)
policy mapping: an integer which indicates if policy mapping
is permitted. The integer indicates the last certificate on which
policy mapping may be applied. Once set, this variable may be
decreased, but may not be increased.
(That is, if a certificate in
the path specifies policy mapping is not
permitted, it can not be
overriden by a later certificate.) The
initial value is n+1.
The actions performed by the path
processing software for each
certificate i=1 through n are described
below. The self-signed
certificate is certificate i=1, the end
entity certificate is i=n.
The processing is performed sequentially,
so that processing
certificate i affects the state variables for
processing certificate
(i+1). Note that actions (h) through (m)
are not applied to the end
entity certificate (certificate n).
The path processing actions to be performed
are:
(a)
Verify the basic certificate information, including:
(1) the certificate was signed using
the subject public key
from certificate i-1 (in the special
case i=1, this step may be
omitted; if not, use the subject
public key from the same
certificate),
(2) the certificate validity period
includes time T,
(3) the certificate had not been
revoked at time T and is not
currently on hold status that
commenced before time T, (this
may be determined by obtaining the
appropriate CRL or status
information, or by out-of-band
mechanisms), and
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(4) the subject and issuer names
chain correctly (that is, the
issuer of this certificate was the
subject of the previous
certificate.)
(b)
Verify that the subject name and subjectAltName extension
(critical or noncritical) is consistent
with the constrained
subtrees state variables.
(c)
Verify that the subject name and subjectAltName extension
(critical or noncritical) is consistent
with the excluded subtrees
state variables.
(d)
Verify that policy information is consistent with the initial
policy set:
(1) if the explicit policy state
variable is less than or equal
to i, a policy identifier in the
certificate shall be in the
initial policy set; and
(2) if the policy mapping variable is less than or equal to
i,
the policy identifier may not be
mapped.
(e)
Verify that policy information is consistent with the
acceptable policy set:
(1) if the certificate policies
extension is marked critical,
the intersection of the policies
extension and the acceptable
policy set shall be non-null;
(2) the acceptable policy set is
assigned the resulting
intersection as its new value.
(g) Verify that the intersection of the
acceptable policy set and
the initial policy set is non-null.
(h)
Recognize and process any other critical extension present in
the certificate.
(i) Verify that the certificate is a CA
certificate (as specified
in a basicConstraints extension or as
verified out-of-band).
(j)
If permittedSubtrees is present in the certificate, set the
constrained subtrees state variable to
the intersection of its
previous value and the value indicated in the extension field.
(k)
If excludedSubtrees is present in the certificate, set the
excluded subtrees state variable to the
union of its previous
value and the value indicated in the
extension field.
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(l)
If a policy constraints extension is included in the
certificate, modify the explicit policy
and policy mapping state
variables as follows:
(1) If requireExplicitPolicy is
present and has value r, the
explicit policy state variable is set
to the minimum of its
current value and the sum of r and i
(the current certificate
in the sequence).
(2) If inhibitPolicyMapping is
present and has value q, the
policy mapping state variable is set
to the minimum of its
current value and the sum of q and i
(the current certificate
in the sequence).
(m) If a key usage extension is marked
critical, ensure the
keyCertSign bit is set.
If any one of the above checks fail, the
procedure terminates,
returning a failure indication and an
appropriate reason. If none of
the above checks fail on the end-entity
certificate, the procedure
terminates, returning a success indication
together with the set of
all policy qualifier values encountered in
the set of certificates.
6.2
Extending Path Validation
The path validation algorithm presented in
6.1 is based on several
simplifying assumptions (e.g., a single
trusted CA that starts all
valid paths). This algorithm may be
extended for cases where the
assumptions do not hold.
This procedure may be extended for multiple
trusted CAs by providing
a set of self-signed certificates to the
validation module. In this
case, a valid path could begin with any one
of the self-signed
certificates. Limitations in the trust paths for any particular key
may be incorporated into the self-signed
certificate's extensions. In
this way, the self-signed certificates
permit the path validation
module to automatically incorporate local
security policy and
requirements.
It is also possible to specify an extended
version of the above
certification path processing procedure
which results in default
behavior identical to the rules of PEM [RFC
1422]. In this extended
version, additional inputs to the procedure
are a list of one or more
Policy Certification Authorities (PCAs)
names and an indicator of the
position in the certification path where
the PCA is expected. At the
nominated PCA position, the CA name is
compared against this list.
If a recognized PCA name is found, then a
constraint of
SubordinateToCA is implicitly assumed for
the remainder of the
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certification path and processing
continues. If no valid PCA name is
found, and if the certification path cannot
be validated on the basis
of identified policies, then the
certification path is considered
invalid.
7 Algorithm Support
This section describes cryptographic
algorithms which may be used
with this profile. The section describes one-way hash functions
and
digital signature algorithms which may be
used to sign certificates
and CRLs, and identifies OIDs for public
keys contained in a
certificate.
Conforming CAs and applications are not
required to support the
algorithms or algorithm identifiers
described in this section.
However, conforming CAs and applications
that use the algorithms
identified here MUST support them as
specified.
7.1 One-way Hash Functions
This section identifies one-way hash
functions for use in the
Internet PKI. One-way hash functions are also called message digest
algorithms. SHA-1 is the preferred one-way
hash function for the
Internet PKI. However, PEM uses MD2 for certificates [RFC 1422] [RFC
1423] and MD5 is used in other legacy
applications. For this reason,
MD2 and MD5 are included in this profile.
7.1.1 MD2 One-way Hash Function
MD2 was developed by Ron Rivest for RSA
Data Security. RSA Data
Security has not placed the MD2 algorithm
in the public domain.
Rather, RSA Data Security has granted
license to use MD2 for non-
commercial Internet Privacy-Enhanced
Mail. For this reason, MD2 may
continue to be used with PEM certificates,
but SHA-1 is preferred.
MD2 produces a 128-bit "hash" of
the input. MD2 is fully described
in RFC 1319 [RFC 1319].
At the Selected Areas in Cryptography '95
conference in May 1995,
Rogier and Chauvaud presented an attack on
MD2 that can nearly find
collisions [RC95]. Collisions occur when one can find two
different
messages that generate the same message
digest. A checksum operation
in MD2 is the only remaining obstacle to
the success of the attack.
For this reason, the use of MD2 for new
applications is discouraged.
It is still reasonable to use MD2 to verify
existing signatures, as
the ability to find collisions in MD2 does
not enable an attacker to
find new messages having a previously
computed hash value.
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7.1.2 MD5 One-way Hash Function
MD5 was developed by Ron Rivest for RSA
Data Security. RSA Data
Security has placed the MD5 algorithm in
the public domain. MD5
produces a 128-bit "hash" of the
input. MD5 is fully described in
RFC 1321 [RFC 1321].
Den Boer and Bosselaers [DB94] have found
pseudo-collisions for MD5,
but there are no other known cryptanalytic
results. The use of MD5
for new applications is discouraged. It is still reasonable to use
MD5 to verify existing signatures.
7.1.3 SHA-1 One-way Hash Function
SHA-1 was developed by the U.S.
Government. SHA-1 produces a 160-bit
"hash" of the input. SHA-1 is
fully described in FIPS 180-1 [FIPS
180-1].
SHA-1 is the one-way hash function of
choice for use with both the
RSA and DSA signature algorithms (see sec.
7.2).
7.2 Signature Algorithms
Certificates and CRLs described by this
standard may be signed with
any public key signature algorithm. The certificate or CRL indicates
the algorithm through an algorithm
identifier which appears in the
signatureAlgorithm field in a Certificate
or CertificateList. This
algorithm identifier is an OID and has
optionally associated
parameters. This section identifies algorithm identifiers and
parameters that shall be used in the
signatureAlgorithm field in a
Certificate or CertificateList.
RSA and DSA are the most popular signature
algorithms used in the
Internet.
Signature algorithms are always used in conjunction with a
one-way hash function identified in section
7.1.
The signature algorithm and one-way hash
function used to sign a
certificate or CRL is indicated by use of
an algorithm identifier.
An algorithm identifier is an OID, and may
include associated
parameters. This section identifies OIDS for RSA and DSA. The
contents of the parameters component for
each algorithm vary; details
are provided for each algorithm.
The data to be signed (e.g., the one-way
hash function output value)
is formatted for the signature algorithm to
be used. Then, a private
key operation (e.g., RSA encryption) is
performed to generate the
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signature value. This signature value is then ASN.1 encoded as a BIT
STRING and included in the Certificate or
CertificateList in the
signature field.
7.2.1 RSA Signature Algorithm
A patent statement regarding the RSA
algorithm can be found at the
end of this profile.
The RSA algorithm is named for its
inventors: Rivest, Shamir, and
Adleman.
This profile includes three signature algorithms based on
the RSA asymmetric encryption algorithm.
The signature algorithms
combine RSA with either the MD2, MD5, or
the SHA-1 one-way hash
functions.
The signature algorithm with MD2 and the
RSA encryption algorithm is
defined in PKCS #1 [RFC 2313]. As defined in RFC 2313, the ASN.1 OID
used to identify this signature algorithm
is:
md2WithRSAEncryption OBJECT
IDENTIFIER ::= {
iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1)
pkcs-1(1) 2 }
The signature algorithm with MD5 and the
RSA encryption algorithm is
defined in PKCS #1 [RFC 2313]. As defined in RFC 2313, the ASN.1 OID
used to identify this signature algorithm
is:
md5WithRSAEncryption OBJECT
IDENTIFIER ::= {
iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1)
pkcs-1(1) 4 }
The signature algorithm with SHA-1 and the
RSA encryption algorithm
is implemented using the padding and
encoding conventions described
in PKCS #1 [RFC 2313]. The message digest
is computed using the SHA-1
hash algorithm. The ASN.1 object identifier used to identify this
signature algorithm is:
sha-1WithRSAEncryption OBJECT
IDENTIFIER ::= {
iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
pkcs-1(1) 5 }
When any of these three OIDs appears within
the ASN.1 type
AlgorithmIdentifier, the parameters
component of that type shall be
the ASN.1 type NULL.
The RSA signature generation process and
the encoding of the result
is described in detail in RFC 2313.
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7.2.2 DSA Signature Algorithm
A patent statement regarding the DSA can be
found at the end of this
profile.
The Digital Signature Algorithm (DSA) is
also called the Digital
Signature Standard (DSS). DSA was developed by the U.S. Government,
and DSA is used in conjunction with the the
SHA-1 one-way hash
function.
DSA is fully described in FIPS 186 [FIPS 186]. The ASN.1
OIDs used to identify this signature
algorithm are:
id-dsa-with-sha1 ID ::=
{
iso(1) member-body(2)
us(840) x9-57 (10040)
x9cm(4) 3 }
Where the id-dsa-with-sha1 algorithm
identifier appears as the
algorithm field in an AlgorithmIdentifier,
the encoding shall omit
the parameters field. That is, the AlgorithmIdentifier shall be a
SEQUENCE of one component - the OBJECT
IDENTIFIER id-dsa-with-sha1.
The DSA parameters in the
subjectPublicKeyInfo field of the
certificate of the issuer shall apply to
the verification of the
signature.
When signing, the DSA algorithm generates
two values. These values
are commonly referred to as r and s. To easily transfer these two
values as one signature, they shall be
ASN.1 encoded using the
following ASN.1 structure:
Dss-Sig-Value ::=
SEQUENCE {
r INTEGER,
s INTEGER }
7.3 Subject Public Key Algorithms
Certificates described by this profile may
convey a public key for
any public key algorithm. The certificate
indicates the algorithm
through an algorithm identifier. This algorithm identifier is an OID
and optionally associated parameters.
This section identifies preferred OIDs and
parameters for the RSA,
DSA, and Diffie-Hellman algorithms. Conforming CAs shall use the
identified OIDs when issuing certificates
containing public keys for
these algorithms. Conforming applications
supporting any of these
algorithms shall, at a minimum, recognize
the OID identified in this
section.
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7.3.1 RSA Keys
The OID rsaEncryption identifies RSA public
keys.
pkcs-1 OBJECT IDENTIFIER ::= { iso(1)
member-body(2) us(840)
rsadsi(113549) pkcs(1)
1 }
rsaEncryption OBJECT IDENTIFIER
::= { pkcs-1 1}
The rsaEncryption OID is intended to be
used in the algorithm field
of a value of type AlgorithmIdentifier. The
parameters field shall
have ASN.1 type NULL for this algorithm
identifier.
The RSA public key shall be encoded using
the ASN.1 type
RSAPublicKey:
RSAPublicKey ::= SEQUENCE {
modulus INTEGER, -- n
publicExponent INTEGER
-- e -- }
where modulus is the modulus n, and
publicExponent is the public
exponent e. The DER encoded RSAPublicKey is the value of the BIT
STRING subjectPublicKey.
This OID is used in public key certificates
for both RSA signature
keys and RSA encryption keys. The intended
application for the key
may be indicated in the key usage field
(see sec. 4.2.1.3). The use
of a single key for both signature and
encryption purposes is not
recommended, but is not forbidden.
If the keyUsage extension is present in an
end entity certificate
which conveys an RSA public key, any
combination of the following
values may be present: digitalSignature; nonRepudiation;
keyEncipherment; and dataEncipherment. If the keyUsage extension is
present in a CA certificate which conveys
an RSA public key, any
combination of the following values may be
present:
digitalSignature; nonRepudiation;
keyEncipherment; dataEncipherment;
keyCertSign; and cRLSign. However, this specification RECOMMENDS
that if keyCertSign or cRLSign is present,
both keyEncipherment and
dataEncipherment should not be present.
7.3.2 Diffie-Hellman Key Exchange Key
The Diffie-Hellman OID supported by this
profile is defined by ANSI
X9.42 [X9.42].
dhpublicnumber OBJECT IDENTIFIER ::= {
iso(1) member-body(2)
us(840) ansi-x942(10046)
number-type(2) 1 }
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The dhpublicnumber OID is intended to be
used in the algorithm field
of a value of type AlgorithmIdentifier. The
parameters field of that
type, which has the algorithm-specific
syntax ANY DEFINED BY
algorithm, have the ASN.1 type
DomainParameters for this algorithm.
DomainParameters ::= SEQUENCE {
p INTEGER, -- odd prime, p=jq +1
g INTEGER, -- generator, g
q INTEGER, -- factor of p-1
j INTEGER OPTIONAL, -- subgroup factor
validationParms ValidationParms OPTIONAL }
ValidationParms ::= SEQUENCE {
seed BIT STRING,
pgenCounter INTEGER }
The fields of type DomainParameters have
the following meanings:
p identifies the prime p defining the
Galois field;
g specifies the generator of the
multiplicative subgroup of order
g;
q specifies the prime factor of p-1;
j optionally specifies the value that
satisfies the equation
p=jq+1 to support the optional
verification of group parameters;
seed optionally specifies the bit string
parameter used as the
seed for the system parameter generation
process; and
pgenCounter optionally specifies the
integer value output as part
of the of the system parameter prime
generation process.
If either of the parameter generation
components (pgencounter or
seed) is provided, the other shall be
present as well.
The Diffie-Hellman public key shall be
ASN.1 encoded as an INTEGER;
this encoding shall be used as the contents
(i.e., the value) of the
subjectPublicKey component (a BIT STRING)
of the subjectPublicKeyInfo
data element.
DHPublicKey ::= INTEGER -- public key, y
= g^x mod p
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If the keyUsage extension is present in a
certificate which conveys a
DH public key, the following values may be
present: keyAgreement;
encipherOnly; and decipherOnly. At most one of encipherOnly and
decipherOnly shall be asserted in keyUsage
extension.
7.3.3 DSA Signature Keys
The Digital Signature Algorithm (DSA) is
also known as the Digital
Signature Standard (DSS). The DSA OID supported
by this profile is
id-dsa ID ::= { iso(1) member-body(2)
us(840) x9-57(10040)
x9cm(4) 1 }
The id-dsa algorithm syntax includes
optional parameters. These
parameters are commonly referred to as p,
q, and g. When omitted,
the parameters component shall be omitted
entirely. That is, the
AlgorithmIdentifier shall be a SEQUENCE of
one component - the OBJECT
IDENTIFIER id-dsa.
If the DSA algorithm parameters are present
in the
subjectPublicKeyInfo AlgorithmIdentifier,
the parameters are included
using the following ASN.1 structure:
Dss-Parms ::= SEQUENCE {
p INTEGER,
q INTEGER,
g INTEGER }
If the DSA algorithm parameters are absent
from the
subjectPublicKeyInfo AlgorithmIdentifier
and the CA signed the
subject certificate using DSA, then the
certificate issuer's DSA
parameters apply to the subject's DSA
key. If the DSA algorithm
parameters are absent from the
subjectPublicKeyInfo
AlgorithmIdentifier and the CA signed the
subject certificate using a
signature algorithm other than DSA, then
the subject's DSA parameters
are distributed by other means. If the subjectPublicKeyInfo
AlgorithmIdentifier field omits the
parameters component and the CA
signed the subject with a signature
algorithm other than DSA, then
clients shall reject the certificate.
When signing, DSA algorithm generates two
values. These values are
commonly referred to as r and s. To easily transfer these two values
as one signature, they are ASN.1 encoded
using the following ASN.1
structure:
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Dss-Sig-Value ::=
SEQUENCE {
r INTEGER,
s INTEGER }
The encoded signature is conveyed as the
value of the BIT STRING
signature in a Certificate or
CertificateList.
The DSA public key shall be ASN.1 DER
encoded as an INTEGER; this
encoding shall be used as the contents
(i.e., the value) of the
subjectPublicKey component (a BIT STRING)
of the SubjectPublicKeyInfo
data element.
DSAPublicKey ::= INTEGER -- public
key, Y
If the keyUsage extension is present in an
end entity certificate
which conveys a DSA public key, any
combination of the following
values may be present: digitalSignature; and nonRepudiation.
If the keyUsage extension is present in an
CA certificate which
conveys a DSA public key, any combination
of the following values may
be present: digitalSignature; nonRepudiation; keyCertSign; and
cRLSign.
8
References
[FIPS 180-1] Federal Information Processing Standards Publication
(FIPS PUB) 180-1, Secure Hash
Standard, 17 April 1995.
[Supersedes FIPS PUB 180
dated 11 May 1993.]
[FIPS 186] Federal Information Processing Standards Publication
(FIPS PUB) 186, Digital
Signature Standard, 18 May
1994.
[RC95] Rogier, N. and Chauvaud, P., "The compression function
of MD2 is not collision
free," Presented at Selected
Areas in Cryptography '95,
May 1995.
[RFC 791] Postel, J., "Internet Protocol", STD 5, RFC 791,
September 1981.
[RFC 822] Crocker, D., "Standard for the format of ARPA Internet
text messages", STD 11,
RFC 822, August 1982.
[RFC 1034] Mockapetris, P., "Domain names - concepts and
facilities", STD 13, RFC
1034, November 1987.
[RFC 1319] Kaliski, B., "The MD2 Message-Digest Algorithm," RFC
1319, April 1992.
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2459 Internet X.509 Public Key
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[RFC 1321] Rivest, R., "The MD5 Message-Digest Algorithm," RFC
1321, April 1992.
[RFC 1422] Kent, S., "Privacy
Enhancement for Internet Electronic
Mail: Part II:
Certificate-Based Key Management," RFC
1422, February 1993.
[RFC 1423] Balenson, D., "Privacy Enhancement for Internet
Electronic Mail: Part III:
Algorithms, Modes, and
Identifiers," RFC 1423,
February 1993.
[RFC 1519] Fuller, V., Li, T., Yu, J. and K. Varadhan. "Classless
Inter-Domain Routing (CIDR):
an Address Assignment and
Aggregation Strategy",
RFC 1519, September 1993.
[RFC 1738] Berners-Lee, T., Masinter L., and M. McCahill.
"Uniform Resource
Locators (URL)", RFC 1738, December
1994.
[RFC 1778] Howes, T., Kille S., Yeong, W. and C. Robbins. "The
String Representation of
Standard Attribute Syntaxes,"
RFC 1778, March 1995.
[RFC
1883] Deering, S. and R. Hinden.
"Internet Protocol, Version
6 (IPv6) Specification",
RFC 1883, December 1995.
[RFC 2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP
14, RFC 2119, March 1997.
[RFC 2247] Kille, S., Wahl, M., Grimstad, A., Huber, R. and S.
Sataluri. "Using Domains
in LDAP/X.500 Distinguished
Names", RFC 2247,
January 1998.
[RFC 2277] Alvestrand, H., "IETF Policy on Character Sets and
Languages", RFC 2277,
January 1998.
[RFC 2279] Yergeau, F., "UTF-8, a transformation format of ISO
10646", RFC 2279,
January 1998.
[RFC 2313] Kaliski, B., "PKCS #1: RSA Encryption Version 1.5",
RFC
2313, March 1998.
[SDN.701] SDN.701, "Message Security Protocol 4.0", Revision A
1997-02-06.
[X.208] CCITT Recommendation X.208: Specification of Abstract
Syntax Notation One (ASN.1), 1988.
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RFC
2459 Internet X.509 Public Key
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[X.501] ITU-T Recommendation X.501: Information Technology -
Open Systems Interconnection
- The Directory: Models,
1993.
[X.509] ITU-T Recommendation X.509 (1997 E): Information
Technology - Open Systems
Interconnection - The
Directory: Authentication Framework, June 1997.
[X.520] ITU-T Recommendation X.520: Information Technology -
Open Systems Interconnection
- The Directory: Selected
Attribute Types, 1993.
[X9.42] ANSI X9.42-199x, Public Key Cryptography for The
Financial Services Industry:
Agreement of Symmetric
Algorithm Keys Using
Diffie-Hellman (Working Draft),
December 1997.
[X9.55] ANSI X9.55-1995, Public Key Cryptography For The
Financial Services Industry:
Extensions To Public Key
Certificates And Certificate
Revocation Lists, 8
December, 1995.
[X9.57] ANSI X9.57-199x, Public Key Cryptography For The
Financial Services Industry:
Certificate Management
(Working Draft), 21 June,
1996.
9 Intellectual Property Rights
The IETF has been notified of intellectual
property rights claimed in
regard to some or all of the specification
contained in this
document.
For more information consult the online list of claimed
rights.
The IETF takes no position regarding the
validity or scope of any
intellectual property or other rights that
might be claimed to
pertain to the implementation or use of the
technology described in
this document or the extent to which any
license under such rights
might or might not be available; neither
does it represent that it
has made any effort to identify any such
rights. Information on the
IETF's procedures with respect to rights in
standards-track and
standards-related documentation can be
found in BCP-11. Copies of
claims of rights made available for
publication and any assurances of
licenses to be made available, or the
result of an attempt made to
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obtain a general license or permission for
the use of such
proprietary rights by implementors or users
of this specification can
be obtained from the IETF Secretariat.
10 Security Considerations
The majority of this specification is
devoted to the format and
content of certificates and CRLs. Since certificates and CRLs are
digitally signed, no additional integrity
service is necessary.
Neither certificates nor CRLs need be kept
secret, and unrestricted
and anonymous access to certificates and
CRLs has no security
implications.
However, security factors outside the scope
of this specification
will affect the assurance provided to
certificate users. This
section highlights critical issues that should
be considered by
implementors, administrators, and users.
The procedures performed by CAs and RAs to
validate the binding of
the subject's identity of their public key
greatly affect the
assurance that should be placed in the
certificate. Relying parties
may wish to review the CA's certificate
practice statement. This may
be particularly important when issuing
certificates to other CAs.
The use of a single key pair for both
signature and other purposes is
strongly discouraged. Use of separate key
pairs for signature and key
management provides several benefits to the
users. The ramifications
associated with loss or disclosure of a
signature key are different
from loss or disclosure of a key management
key. Using separate key
pairs permits a balanced and flexible
response. Similarly, different
validity periods or key lengths for each
key pair may be appropriate
in some application environments.
Unfortunately, some legacy
applications (e.g., SSL) use a single key
pair for signature and key
management.
The protection afforded private keys is a
critical factor in
maintaining security. On a small scale, failure of users to
protect
their private keys will permit an attacker to
masquerade as them, or
decrypt their personal information. On a
larger scale, compromise of
a CA's private signing key may have a
catastrophic effect. If an
attacker obtains the private key unnoticed,
the attacker may issue
bogus certificates and CRLs. Existence of bogus certificates and
CRLs will undermine confidence in the
system. If the compromise is
detected, all certificates issued to the CA
shall be revoked,
preventing services between its users and
users of other CAs.
Rebuilding after such a compromise will be
problematic, so CAs are
advised to implement a combination of
strong technical measures
(e.g., tamper-resistant cryptographic
modules) and appropriate
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management procedures (e.g., separation of
duties) to avoid such an
incident.
Loss of a CA's private signing key may also
be problematic. The CA
would not be able to produce CRLs or
perform normal key rollover.
CAs are advised to maintain secure backup
for signing keys. The
security of the key backup procedures is a
critical factor in
avoiding key compromise.
The availability and freshness of
revocation information will affect
the degree of assurance that should be
placed in a certificate.
While certificates expire naturally, events
may occur during its
natural lifetime which negate the binding
between the subject and
public key. If revocation information is untimely or unavailable,
the assurance associated with the binding
is clearly reduced.
Similarly, implementations of the Path
Validation mechanism described
in section 6 that omit revocation checking
provide less assurance
than those that support it.
The path validation algorithm depends on
the certain knowledge of the
public keys (and other information) about
one or more trusted CAs.
The decision to trust a CA is an important
decision as it ultimately
determines the trust afforded a
certificate. The authenticated
distribution of trusted CA public keys
(usually in the form of a
"self-signed" certificate) is a
security critical out of band process
that is beyond the scope of this
specification.
In addition, where a key compromise or CA
failure occurs for a
trusted CA, the user will need to modify
the information provided to
the path validation routine. Selection of too many trusted CAs will
make the trusted CA information difficult
to maintain. On the other
hand, selection of only one trusted CA may
limit users to a closed
community of users until a global PKI
emerges.
The quality of implementations that process
certificates may also
affect the degree of assurance
provided. The path validation
algorithm described in section 6 relies
upon the integrity of the
trusted CA information, and especially the
integrity of the public
keys associated with the trusted CAs. By substituting public keys
for which an attacker has the private key,
an attacker could trick
the user into accepting false certificates.
The binding between a key and certificate
subject cannot be stronger
than the cryptographic module
implementation and algorithms used to
generate the signature. Short key lengths or weak hash algorithms
will limit the utility of a
certificate. CAs are encouraged to note
advances in cryptology so they can employ
strong cryptographic
techniques. In addition, CAs should decline to issue certificates to
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CAs or end entities that generate weak
signatures.
Inconsistent application of name comparison
rules may result in
acceptance of invalid X.509 certification
paths, or rejection of
valid ones. The X.500 series of specifications defines rules for
comparing distinguished names require
comparison of strings without
regard to case, character set,
multi-character white space substring,
or leading and trailing white space. This specification relaxes
these requirements, requiring support for
binary comparison at a
minimum.
CAs shall encode the distinguished name in
the subject field of a CA
certificate identically to the
distinguished name in the issuer field
in certificates issued by the latter
CA. If CAs use different
encodings, implementations of this
specification may fail to
recognize name chains for paths that
include this certificate. As a
consequence, valid paths could be rejected.
In addition, name constraints for
distinguished names shall be stated
identically to the encoding used in the subject field or
subjectAltName extension. If not, (1) name constraints stated as
excludedSubTrees will not match and invalid
paths will be accepted
and (2) name constraints expressed as
permittedSubtrees will not
match and valid paths will be
rejected. To avoid acceptance of
invalid paths, CAs should state name
constraints for distinguished
names as permittedSubtrees where ever
possible.
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Appendix
A. Psuedo-ASN.1 Structures and OIDs
This section describes data objects used by
conforming PKI components
in an "ASN.1-like" syntax. This syntax is a hybrid of the 1988 and
1993 ASN.1 syntaxes. The 1988 ASN.1 syntax is augmented with 1993
UNIVERSAL Types UniversalString, BMPString
and UTF8String.
The ASN.1 syntax does not permit the
inclusion of type statements in
the ASN.1 module, and the 1993 ASN.1
standard does not permit use of
the new UNIVERSAL types in modules using
the 1988 syntax. As a
result, this module does not conform to
either version of the ASN.1
standard.
This appendix may be converted into 1988
ASN.1 by replacing the
defintions for the UNIVERSAL Types with the
1988 catch-all "ANY".
A.1
Explicitly Tagged Module, 1988 Syntax
PKIX1Explicit88
{iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0)
id-pkix1-explicit-88(1)}
DEFINITIONS
EXPLICIT TAGS ::=
BEGIN
--
EXPORTS ALL --
--
IMPORTS NONE --
--
UNIVERSAL Types defined in '93 and '98 ASN.1
-- but
required by this specification
UniversalString
::= [UNIVERSAL 28] IMPLICIT OCTET STRING
-- UniversalString is defined in
ASN.1:1993
BMPString
::= [UNIVERSAL 30] IMPLICIT OCTET STRING
-- BMPString is the subtype of
UniversalString and models
-- the Basic Multilingual Plane of
ISO/IEC/ITU 10646-1
UTF8String
::= [UNIVERSAL 12] IMPLICIT OCTET STRING
-- The content of this type conforms
to RFC 2279.
--
-- PKIX
specific OIDs
id-pkix OBJECT IDENTIFIER ::=
{ iso(1) identified-organization(3)
dod(6) internet(1)
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security(5) mechanisms(5)
pkix(7) }
-- PKIX
arcs
id-pe
OBJECT IDENTIFIER ::= { id-pkix 1 }
-- arc for private certificate
extensions
id-qt
OBJECT IDENTIFIER ::= { id-pkix 2 }
-- arc for policy qualifier types
id-kp
OBJECT IDENTIFIER ::= { id-pkix 3 }
-- arc for extended key purpose OIDS
id-ad
OBJECT IDENTIFIER ::= { id-pkix 48 }
-- arc for access descriptors
--
policyQualifierIds for Internet policy qualifiers
id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
-- OID for CPS qualifier
id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
-- OID for user notice qualifier
--
access descriptor definitions
id-ad-ocsp OBJECT IDENTIFIER ::= { id-ad 1 }
id-ad-caIssuers
OBJECT IDENTIFIER ::= { id-ad 2 }
--
attribute data types --
Attribute ::=
SEQUENCE {
type AttributeType,
values SET OF AttributeValue
-- at least one value is
required -- }
AttributeType ::= OBJECT IDENTIFIER
AttributeValue ::= ANY
AttributeTypeAndValue ::= SEQUENCE {
type AttributeType,
value AttributeValue }
--
suggested naming attributes: Definition of the following
-- information object set may be augmented to
meet local
-- requirements. Note that deleting members of the set may
-- prevent interoperability with conforming
implementations.
-- presented in pairs: the AttributeType
followed by the
-- type definition for the corresponding
AttributeValue
--Arc
for standard naming attributes
id-at OBJECT IDENTIFIER ::=
{joint-iso-ccitt(2) ds(5) 4}
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-- Attributes
of type NameDirectoryString
id-at-name AttributeType ::=
{id-at 41}
id-at-surname AttributeType ::=
{id-at 4}
id-at-givenName AttributeType ::=
{id-at 42}
id-at-initials AttributeType ::=
{id-at 43}
id-at-generationQualifier AttributeType ::= {id-at 44}
X520name ::= CHOICE {
teletexString TeletexString (SIZE (1..ub-name)),
printableString PrintableString (SIZE (1..ub-name)),
universalString
UniversalString (SIZE (1..ub-name)),
utf8String UTF8String (SIZE (1..ub-name)),
bmpString BMPString (SIZE(1..ub-name)) }
--
id-at-commonName AttributeType ::=
{id-at 3}
X520CommonName ::=
CHOICE {
teletexString TeletexString (SIZE (1..ub-common-name)),
printableString PrintableString (SIZE
(1..ub-common-name)),
universalString UniversalString (SIZE
(1..ub-common-name)),
utf8String
UTF8String (SIZE (1..ub-common-name)),
bmpString BMPString (SIZE(1..ub-common-name)) }
--
id-at-localityName AttributeType ::= {id-at 7}
X520LocalityName
::= CHOICE {
teletexString TeletexString (SIZE
(1..ub-locality-name)),
printableString PrintableString (SIZE
(1..ub-locality-name)),
universalString UniversalString (SIZE
(1..ub-locality-name)),
utf8String UTF8String (SIZE (1..ub-locality-name)),
bmpString BMPString (SIZE(1..ub-locality-name)) }
--
id-at-stateOrProvinceName AttributeType ::= {id-at 8}
X520StateOrProvinceName ::= CHOICE {
teletexString TeletexString (SIZE (1..ub-state-name)),
printableString PrintableString (SIZE
(1..ub-state-name)),
universalString UniversalString (SIZE
(1..ub-state-name)),
utf8String UTF8String (SIZE (1..ub-state-name)),
bmpString BMPString (SIZE(1..ub-state-name)) }
--
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id-at-organizationName AttributeType ::=
{id-at 10}
X520OrganizationName
::= CHOICE {
teletexString TeletexString (SIZE (1..ub-organization-name)),
printableString PrintableString (SIZE (1..ub-organization-name)),
universalString UniversalString (SIZE (1..ub-organization-name)),
utf8String UTF8String (SIZE (1..ub-organization-name)),
bmpString BMPString (SIZE(1..ub-organization-name)) }
--
id-at-organizationalUnitName AttributeType ::= {id-at 11}
X520OrganizationalUnitName
::= CHOICE {
teletexString TeletexString (SIZE (1..ub-organizational-unit-name)),
printableString PrintableString
(SIZE
(1..ub-organizational-unit-name)),
universalString UniversalString
(SIZE (1..ub-organizational-unit-name)),
utf8String UTF8String (SIZE (1..ub-organizational-unit-name)),
bmpString BMPString (SIZE(1..ub-organizational-unit-name)) }
--
id-at-title AttributeType ::= {id-at 12}
X520Title
::= CHOICE {
teletexString TeletexString (SIZE (1..ub-title)),
printableString PrintableString (SIZE (1..ub-title)),
universalString UniversalString (SIZE (1..ub-title)),
utf8String UTF8String (SIZE (1..ub-title)),
bmpString BMPString
(SIZE(1..ub-title)) }
--
id-at-dnQualifier AttributeType ::= {id-at 46}
X520dnQualifier
::= PrintableString
id-at-countryName AttributeType ::= {id-at 6}
X520countryName
::= PrintableString (SIZE (2)) -- IS
3166 codes
-- Legacy attributes
pkcs-9
OBJECT IDENTIFIER ::=
{ iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) 9 }
emailAddress
AttributeType ::= { pkcs-9 1 }
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Pkcs9email
::= IA5String (SIZE (1..ub-emailaddress-length))
--
naming data types --
Name ::= CHOICE { -- only one possibility for now --
rdnSequence RDNSequence }
RDNSequence ::=
SEQUENCE OF RelativeDistinguishedName
DistinguishedName ::=
RDNSequence
RelativeDistinguishedName ::=
SET SIZE (1 .. MAX) OF
AttributeTypeAndValue
--
Directory string type --
DirectoryString
::= CHOICE {
teletexString TeletexString (SIZE (1..MAX)),
printableString PrintableString (SIZE (1..MAX)),
universalString UniversalString (SIZE (1..MAX)),
utf8String UTF8String (SIZE (1..MAX)),
bmpString BMPString (SIZE(1..MAX)) }
--
certificate and CRL specific structures begin here
Certificate ::=
SEQUENCE {
tbsCertificate
TBSCertificate,
signatureAlgorithm AlgorithmIdentifier,
signature BIT STRING }
TBSCertificate ::=
SEQUENCE {
version [0] Version
DEFAULT v1,
serialNumber CertificateSerialNumber,
signature AlgorithmIdentifier,
issuer Name,
validity Validity,
subject Name,
subjectPublicKeyInfo
SubjectPublicKeyInfo,
issuerUniqueID [1] IMPLICIT UniqueIdentifier
OPTIONAL,
-- If present,
version shall be v2 or v3
subjectUniqueID [2] IMPLICIT UniqueIdentifier OPTIONAL,
-- If present,
version shall be v2 or v3
extensions [3] Extensions OPTIONAL
-- If present,
version shall be v3 -- }
Version ::=
INTEGER { v1(0), v2(1), v3(2) }
CertificateSerialNumber ::=
INTEGER
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Validity
::= SEQUENCE {
notBefore Time,
notAfter Time }
Time
::= CHOICE {
utcTime UTCTime,
generalTime GeneralizedTime }
UniqueIdentifier ::=
BIT STRING
SubjectPublicKeyInfo ::=
SEQUENCE {
algorithm AlgorithmIdentifier,
subjectPublicKey BIT STRING }
Extensions ::=
SEQUENCE SIZE (1..MAX) OF Extension
Extension ::=
SEQUENCE {
extnID
OBJECT IDENTIFIER,
critical BOOLEAN DEFAULT FALSE,
extnValue OCTET STRING }
-- CRL
structures
CertificateList ::=
SEQUENCE {
tbsCertList TBSCertList,
signatureAlgorithm AlgorithmIdentifier,
signature BIT STRING }
TBSCertList ::=
SEQUENCE {
version Version OPTIONAL,
-- if
present, shall be v2
signature AlgorithmIdentifier,
issuer Name,
thisUpdate Time,
nextUpdate Time OPTIONAL,
revokedCertificates SEQUENCE OF SEQUENCE {
userCertificate CertificateSerialNumber,
revocationDate Time,
crlEntryExtensions Extensions OPTIONAL
-- if
present, shall be v2
} OPTIONAL,
crlExtensions [0] Extensions OPTIONAL
-- if
present, shall be v2 -- }
--
Version, Time, CertificateSerialNumber, and Extensions were
--
defined earlier for use in the certificate structure
AlgorithmIdentifier ::=
SEQUENCE {
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algorithm OBJECT IDENTIFIER,
parameters ANY DEFINED BY algorithm OPTIONAL }
-- contains a
value of the type
-- registered
for use with the
-- algorithm
object identifier value
--
Algorithm OIDs and parameter structures
pkcs-1
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) 1 }
rsaEncryption
OBJECT IDENTIFIER ::= { pkcs-1 1 }
md2WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 2 }
md5WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 4 }
sha1WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 5 }
id-dsa-with-sha1
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840) x9-57
(10040) x9algorithm(4) 3 }
Dss-Sig-Value ::=
SEQUENCE {
r
INTEGER,
s
INTEGER }
dhpublicnumber
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840)
ansi-x942(10046) number-type(2) 1 }
DomainParameters
::= SEQUENCE {
p
INTEGER, -- odd prime, p=jq +1
g
INTEGER, -- generator, g
q
INTEGER, -- factor of p-1
j
INTEGER OPTIONAL, -- subgroup factor, j>= 2
validationParms ValidationParms OPTIONAL }
ValidationParms
::= SEQUENCE {
seed BIT STRING,
pgenCounter INTEGER }
id-dsa
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840) x9-57(10040)
x9algorithm(4) 1 }
Dss-Parms ::=
SEQUENCE {
p INTEGER,
q INTEGER,
g INTEGER }
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-- x400
address syntax starts here
-- OR Names
ORAddress
::= SEQUENCE {
built-in-standard-attributes
BuiltInStandardAttributes,
built-in-domain-defined-attributes
BuiltInDomainDefinedAttributes OPTIONAL,
-- see also
teletex-domain-defined-attributes
extension-attributes ExtensionAttributes
OPTIONAL }
-- The OR-address is semantically absent
from the OR-name if the
-- built-in-standard-attribute sequence is
empty and the
-- built-in-domain-defined-attributes and
extension-attributes are
-- both omitted.
-- Built-in Standard Attributes
BuiltInStandardAttributes
::= SEQUENCE {
country-name CountryName OPTIONAL,
administration-domain-name AdministrationDomainName OPTIONAL,
network-address [0] NetworkAddress OPTIONAL,
-- see also extended-network-address
terminal-identifier [1] TerminalIdentifier OPTIONAL,
private-domain-name [2] PrivateDomainName OPTIONAL,
organization-name [3] OrganizationName OPTIONAL,
-- see also teletex-organization-name
numeric-user-identifier [4] NumericUserIdentifier OPTIONAL,
personal-name [5] PersonalName OPTIONAL,
-- see also teletex-personal-name
organizational-unit-names [6] OrganizationalUnitNames OPTIONAL
-- see also
teletex-organizational-unit-names -- }
CountryName
::= [APPLICATION 1] CHOICE {
x121-dcc-code NumericString
(SIZE (ub-country-name-numeric-length)),
iso-3166-alpha2-code PrintableString
(SIZE
(ub-country-name-alpha-length)) }
AdministrationDomainName
::= [APPLICATION 2] CHOICE {
numeric NumericString (SIZE
(0..ub-domain-name-length)),
printable PrintableString (SIZE
(0..ub-domain-name-length)) }
NetworkAddress
::= X121Address -- see also
extended-network-address
X121Address
::= NumericString (SIZE (1..ub-x121-address-length))
TerminalIdentifier
::= PrintableString (SIZE (1..ub-terminal-id-length))
PrivateDomainName
::= CHOICE {
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numeric NumericString (SIZE
(1..ub-domain-name-length)),
printable PrintableString (SIZE
(1..ub-domain-name-length)) }
OrganizationName
::= PrintableString
(SIZE
(1..ub-organization-name-length))
-- see
also teletex-organization-name
NumericUserIdentifier
::= NumericString
(SIZE
(1..ub-numeric-user-id-length))
PersonalName
::= SET {
surname [0] PrintableString (SIZE
(1..ub-surname-length)),
given-name [1] PrintableString
(SIZE
(1..ub-given-name-length)) OPTIONAL,
initials [2] PrintableString (SIZE
(1..ub-initials-length)) OPTIONAL,
generation-qualifier [3] PrintableString
(SIZE
(1..ub-generation-qualifier-length)) OPTIONAL }
-- see
also teletex-personal-name
OrganizationalUnitNames
::= SEQUENCE SIZE (1..ub-organizational-units)
OF
OrganizationalUnitName
-- see
also teletex-organizational-unit-names
OrganizationalUnitName
::= PrintableString (SIZE
(1..ub-organizational-unit-name-length))
-- Built-in Domain-defined Attributes
BuiltInDomainDefinedAttributes
::= SEQUENCE SIZE
(1..ub-domain-defined-attributes) OF
BuiltInDomainDefinedAttribute
BuiltInDomainDefinedAttribute
::= SEQUENCE {
type PrintableString (SIZE
(1..ub-domain-defined-attribute-type-length)),
value PrintableString (SIZE
(1..ub-domain-defined-attribute-value-length))}
-- Extension Attributes
ExtensionAttributes
::= SET SIZE (1..ub-extension-attributes) OF
ExtensionAttribute
ExtensionAttribute
::= SEQUENCE {
extension-attribute-type [0] INTEGER
(0..ub-extension-attributes),
extension-attribute-value [1]
ANY DEFINED BY
extension-attribute-type }
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--
Extension types and attribute values
--
common-name
INTEGER ::= 1
CommonName
::= PrintableString (SIZE (1..ub-common-name-length))
teletex-common-name
INTEGER ::= 2
TeletexCommonName
::= TeletexString (SIZE (1..ub-common-name-length))
teletex-organization-name
INTEGER ::= 3
TeletexOrganizationName
::=
TeletexString (SIZE
(1..ub-organization-name-length))
teletex-personal-name
INTEGER ::= 4
TeletexPersonalName
::= SET {
surname [0] TeletexString (SIZE
(1..ub-surname-length)),
given-name [1] TeletexString
(SIZE
(1..ub-given-name-length)) OPTIONAL,
initials [2] TeletexString (SIZE
(1..ub-initials-length)) OPTIONAL,
generation-qualifier [3] TeletexString
(SIZE
(1..ub-generation-qualifier-length)) OPTIONAL }
teletex-organizational-unit-names
INTEGER ::= 5
TeletexOrganizationalUnitNames
::= SEQUENCE SIZE
(1..ub-organizational-units) OF
TeletexOrganizationalUnitName
TeletexOrganizationalUnitName
::= TeletexString
(SIZE
(1..ub-organizational-unit-name-length))
pds-name
INTEGER ::= 7
PDSName
::= PrintableString (SIZE (1..ub-pds-name-length))
physical-delivery-country-name
INTEGER ::= 8
PhysicalDeliveryCountryName
::= CHOICE {
x121-dcc-code NumericString (SIZE
(ub-country-name-numeric-length)),
iso-3166-alpha2-code PrintableString
(SIZE
(ub-country-name-alpha-length)) }
postal-code
INTEGER ::= 9
PostalCode
::= CHOICE {
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numeric-code NumericString (SIZE
(1..ub-postal-code-length)),
printable-code PrintableString (SIZE
(1..ub-postal-code-length)) }
physical-delivery-office-name
INTEGER ::= 10
PhysicalDeliveryOfficeName
::= PDSParameter
physical-delivery-office-number
INTEGER ::= 11
PhysicalDeliveryOfficeNumber
::= PDSParameter
extension-OR-address-components
INTEGER ::= 12
ExtensionORAddressComponents
::= PDSParameter
physical-delivery-personal-name
INTEGER ::= 13
PhysicalDeliveryPersonalName
::= PDSParameter
physical-delivery-organization-name
INTEGER ::= 14
PhysicalDeliveryOrganizationName
::= PDSParameter
extension-physical-delivery-address-components
INTEGER ::= 15
ExtensionPhysicalDeliveryAddressComponents
::= PDSParameter
unformatted-postal-address
INTEGER ::= 16
UnformattedPostalAddress
::= SET {
printable-address SEQUENCE SIZE
(1..ub-pds-physical-address-lines) OF
PrintableString (SIZE
(1..ub-pds-parameter-length)) OPTIONAL,
teletex-string TeletexString
(SIZE
(1..ub-unformatted-address-length)) OPTIONAL }
street-address
INTEGER ::= 17
StreetAddress
::= PDSParameter
post-office-box-address
INTEGER ::= 18
PostOfficeBoxAddress
::= PDSParameter
poste-restante-address
INTEGER ::= 19
PosteRestanteAddress
::= PDSParameter
unique-postal-name
INTEGER ::= 20
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UniquePostalName
::= PDSParameter
local-postal-attributes
INTEGER ::= 21
LocalPostalAttributes
::= PDSParameter
PDSParameter
::= SET {
printable-string PrintableString
(SIZE(1..ub-pds-parameter-length)) OPTIONAL,
teletex-string TeletexString
(SIZE(1..ub-pds-parameter-length)) OPTIONAL }
extended-network-address
INTEGER ::= 22
ExtendedNetworkAddress
::= CHOICE {
e163-4-address SEQUENCE {
number [0] NumericString (SIZE
(1..ub-e163-4-number-length)),
sub-address [1] NumericString
(SIZE
(1..ub-e163-4-sub-address-length)) OPTIONAL },
psap-address [0] PresentationAddress }
PresentationAddress
::= SEQUENCE {
pSelector [0] EXPLICIT OCTET STRING OPTIONAL,
sSelector [1] EXPLICIT OCTET STRING OPTIONAL,
tSelector [2] EXPLICIT OCTET STRING OPTIONAL,
nAddresses [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING }
terminal-type INTEGER ::= 23
TerminalType
::= INTEGER {
telex (3),
teletex (4),
g3-facsimile (5),
g4-facsimile (6),
ia5-terminal (7),
videotex (8) } (0..ub-integer-options)
-- Extension Domain-defined Attributes
teletex-domain-defined-attributes
INTEGER ::= 6
TeletexDomainDefinedAttributes
::= SEQUENCE SIZE
(1..ub-domain-defined-attributes) OF
TeletexDomainDefinedAttribute
TeletexDomainDefinedAttribute
::= SEQUENCE {
type TeletexString
(SIZE
(1..ub-domain-defined-attribute-type-length)),
value TeletexString
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Infrastructure January 1999
(SIZE
(1..ub-domain-defined-attribute-value-length)) }
-- specifications of Upper Bounds shall be
regarded as mandatory
-- from Annex B of ITU-T X.411 Reference
Definition of MTS Parameter
-- Upper Bounds
-- Upper Bounds
ub-name
INTEGER ::= 32768
ub-common-name INTEGER ::= 64
ub-locality-name INTEGER ::= 128
ub-state-name INTEGER ::= 128
ub-organization-name INTEGER ::= 64
ub-organizational-unit-name INTEGER ::= 64
ub-title INTEGER ::= 64
ub-match INTEGER ::= 128
ub-emailaddress-length
INTEGER ::= 128
ub-common-name-length
INTEGER ::= 64
ub-country-name-alpha-length
INTEGER ::= 2
ub-country-name-numeric-length
INTEGER ::= 3
ub-domain-defined-attributes
INTEGER ::= 4
ub-domain-defined-attribute-type-length
INTEGER ::= 8
ub-domain-defined-attribute-value-length
INTEGER ::= 128
ub-domain-name-length
INTEGER ::= 16
ub-extension-attributes
INTEGER ::= 256
ub-e163-4-number-length
INTEGER ::= 15
ub-e163-4-sub-address-length
INTEGER ::= 40
ub-generation-qualifier-length
INTEGER ::= 3
ub-given-name-length
INTEGER ::= 16
ub-initials-length
INTEGER ::= 5
ub-integer-options
INTEGER ::= 256
ub-numeric-user-id-length
INTEGER ::= 32
ub-organization-name-length
INTEGER ::= 64
ub-organizational-unit-name-length
INTEGER ::= 32
ub-organizational-units
INTEGER ::= 4
ub-pds-name-length
INTEGER ::= 16
ub-pds-parameter-length
INTEGER ::= 30
ub-pds-physical-address-lines
INTEGER ::= 6
ub-postal-code-length
INTEGER ::= 16
ub-surname-length
INTEGER ::= 40
ub-terminal-id-length
INTEGER ::= 24
ub-unformatted-address-length
INTEGER ::= 180
ub-x121-address-length
INTEGER ::= 16
-- Note
- upper bounds on string types, such as TeletexString, are
--
measured in characters. Excepting
PrintableString or IA5String, a
--
significantly greater number of octets will be required to hold
Housley,
et. al. Standards Track [Page 82]
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Infrastructure January 1999
-- such
a value. As a minimum, 16 octets, or
twice the specified upper
--
bound, whichever is the larger, should be allowed for TeletexString.
-- For
UTF8String or UniversalString at least four times the upper
--
bound should be allowed.
END
Housley,
et. al. Standards Track [Page 83]
RFC
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Infrastructure January 1999
A.2
Implicitly Tagged Module, 1988 Syntax
PKIX1Implicit88
{iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0) id-pkix1-implicit-88(2)}
DEFINITIONS
IMPLICIT TAGS ::=
BEGIN
--
EXPORTS ALL --
IMPORTS
id-pkix, id-pe, id-qt, id-kp,
id-qt-unotice, id-qt-cps,
id-ad, id-ad-ocsp,
id-ad-caIssuers,
-- delete following line if
"new" types are supported --
BMPString, UniversalString,
UTF8String, -- end "new" types
ORAddress, Name,
RelativeDistinguishedName,
CertificateSerialNumber,
CertificateList,
AlgorithmIdentifier, ub-name,
Attribute, DirectoryString
FROM PKIX1Explicit88 {iso(1)
identified-organization(3)
dod(6) internet(1) security(5)
mechanisms(5) pkix(7)
id-mod(0)
id-pkix1-explicit(1)};
-- ISO
arc for standard certificate and CRL extensions
id-ce
OBJECT IDENTIFIER ::= {joint-iso-ccitt(2) ds(5) 29}
--
authority key identifier OID and syntax
id-ce-authorityKeyIdentifier
OBJECT IDENTIFIER ::= { id-ce 35 }
AuthorityKeyIdentifier
::= SEQUENCE {
keyIdentifier [0] KeyIdentifier OPTIONAL,
authorityCertIssuer [1] GeneralNames OPTIONAL,
authorityCertSerialNumber [2]
CertificateSerialNumber OPTIONAL }
-- authorityCertIssuer and
authorityCertSerialNumber shall both
-- be present or both be absent
KeyIdentifier
::= OCTET STRING
--
subject key identifier OID and syntax
id-ce-subjectKeyIdentifier
OBJECT IDENTIFIER ::= { id-ce 14 }
SubjectKeyIdentifier
::= KeyIdentifier
Housley,
et. al. Standards Track [Page 84]
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Infrastructure January 1999
-- key
usage extension OID and syntax
id-ce-keyUsage
OBJECT IDENTIFIER ::= { id-ce 15 }
KeyUsage
::= BIT STRING {
digitalSignature (0),
nonRepudiation (1),
keyEncipherment (2),
dataEncipherment (3),
keyAgreement (4),
keyCertSign (5),
cRLSign (6),
encipherOnly (7),
decipherOnly (8) }
--
private key usage period extension OID and syntax
id-ce-privateKeyUsagePeriod
OBJECT IDENTIFIER ::= { id-ce 16 }
PrivateKeyUsagePeriod
::= SEQUENCE {
notBefore [0]
GeneralizedTime OPTIONAL,
notAfter [1]
GeneralizedTime OPTIONAL }
-- either notBefore or notAfter shall be
present
--
certificate policies extension OID and syntax
id-ce-certificatePolicies
OBJECT IDENTIFIER ::= { id-ce 32 }
CertificatePolicies
::= SEQUENCE SIZE (1..MAX) OF PolicyInformation
PolicyInformation
::= SEQUENCE {
policyIdentifier CertPolicyId,
policyQualifiers SEQUENCE SIZE (1..MAX) OF
PolicyQualifierInfo OPTIONAL }
CertPolicyId
::= OBJECT IDENTIFIER
PolicyQualifierInfo
::= SEQUENCE {
policyQualifierId PolicyQualifierId,
qualifier ANY DEFINED BY policyQualifierId }
--
Implementations that recognize additional policy qualifiers shall
--
augment the following definition for PolicyQualifierId
PolicyQualifierId
::=
OBJECT IDENTIFIER ( id-qt-cps |
id-qt-unotice )
-- CPS
pointer qualifier
Housley,
et. al. Standards Track [Page 85]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
CPSuri
::= IA5String
-- user
notice qualifier
UserNotice
::= SEQUENCE {
noticeRef NoticeReference OPTIONAL,
explicitText DisplayText OPTIONAL}
NoticeReference
::= SEQUENCE {
organization DisplayText,
noticeNumbers SEQUENCE OF INTEGER }
DisplayText
::= CHOICE {
visibleString VisibleString (SIZE
(1..200)),
bmpString BMPString (SIZE
(1..200)),
utf8String UTF8String (SIZE
(1..200)) }
--
policy mapping extension OID and syntax
id-ce-policyMappings
OBJECT IDENTIFIER ::= { id-ce 33 }
PolicyMappings
::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
issuerDomainPolicy CertPolicyId,
subjectDomainPolicy CertPolicyId }
--
subject alternative name extension OID and syntax
id-ce-subjectAltName
OBJECT IDENTIFIER ::= { id-ce 17 }
SubjectAltName
::= GeneralNames
GeneralNames
::= SEQUENCE SIZE (1..MAX) OF GeneralName
GeneralName
::= CHOICE {
otherName [0]
AnotherName,
rfc822Name [1]
IA5String,
dNSName [2]
IA5String,
x400Address [3] ORAddress,
directoryName [4]
Name,
ediPartyName [5]
EDIPartyName,
uniformResourceIdentifier [6]
IA5String,
iPAddress [7]
OCTET STRING,
registeredID [8]
OBJECT IDENTIFIER }
--
AnotherName replaces OTHER-NAME ::= TYPE-IDENTIFIER, as
--
TYPE-IDENTIFIER is not supported in the '88 ASN.1 syntax
AnotherName
::= SEQUENCE {
Housley,
et. al. Standards Track [Page 86]
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2459 Internet X.509 Public Key
Infrastructure January 1999
type-id OBJECT IDENTIFIER,
value [0] EXPLICIT ANY DEFINED BY type-id }
EDIPartyName
::= SEQUENCE {
nameAssigner [0] DirectoryString OPTIONAL,
partyName [1]
DirectoryString }
--
issuer alternative name extension OID and syntax
id-ce-issuerAltName
OBJECT IDENTIFIER ::= { id-ce 18 }
IssuerAltName
::= GeneralNames
id-ce-subjectDirectoryAttributes
OBJECT IDENTIFIER ::= { id-ce 9 }
SubjectDirectoryAttributes
::= SEQUENCE SIZE (1..MAX) OF Attribute
--
basic constraints extension OID and syntax
id-ce-basicConstraints
OBJECT IDENTIFIER ::= { id-ce 19 }
BasicConstraints
::= SEQUENCE {
cA BOOLEAN DEFAULT FALSE,
pathLenConstraint INTEGER (0..MAX) OPTIONAL }
-- name
constraints extension OID and syntax
id-ce-nameConstraints
OBJECT IDENTIFIER ::= { id-ce 30 }
NameConstraints
::= SEQUENCE {
permittedSubtrees [0]
GeneralSubtrees OPTIONAL,
excludedSubtrees [1] GeneralSubtrees OPTIONAL }
GeneralSubtrees
::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree
GeneralSubtree
::= SEQUENCE {
base
GeneralName,
minimum [0]
BaseDistance DEFAULT 0,
maximum [1]
BaseDistance OPTIONAL }
BaseDistance
::= INTEGER (0..MAX)
--
policy constraints extension OID and syntax
id-ce-policyConstraints
OBJECT IDENTIFIER ::= { id-ce 36 }
PolicyConstraints
::= SEQUENCE {
requireExplicitPolicy [0] SkipCerts OPTIONAL,
Housley,
et. al. Standards Track [Page 87]
RFC
2459 Internet X.509 Public Key Infrastructure January 1999
inhibitPolicyMapping [1] SkipCerts OPTIONAL }
SkipCerts
::= INTEGER (0..MAX)
-- CRL
distribution points extension OID and syntax
id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::=
{id-ce 31}
CRLDistPointsSyntax
::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
DistributionPoint
::= SEQUENCE {
distributionPoint [0]
DistributionPointName OPTIONAL,
reasons [1]
ReasonFlags OPTIONAL,
cRLIssuer [2] GeneralNames OPTIONAL }
DistributionPointName
::= CHOICE {
fullName [0]
GeneralNames,
nameRelativeToCRLIssuer [1] RelativeDistinguishedName }
ReasonFlags
::= BIT STRING {
unused (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6) }
--
extended key usage extension OID and syntax
id-ce-extKeyUsage
OBJECT IDENTIFIER ::= {id-ce 37}
ExtKeyUsageSyntax
::= SEQUENCE SIZE (1..MAX) OF KeyPurposeId
KeyPurposeId
::= OBJECT IDENTIFIER
--
extended key purpose OIDs
id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 }
id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 }
id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 }
id-kp-emailProtection
OBJECT IDENTIFIER ::= { id-kp 4 }
id-kp-ipsecEndSystem OBJECT IDENTIFIER ::= { id-kp 5 }
id-kp-ipsecTunnel OBJECT IDENTIFIER ::= { id-kp 6 }
id-kp-ipsecUser OBJECT IDENTIFIER ::= { id-kp 7 }
id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 }
--
authority info access
Housley,
et. al. Standards Track [Page 88]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
id-pe-authorityInfoAccess
OBJECT IDENTIFIER ::= { id-pe 1 }
AuthorityInfoAccessSyntax ::=
SEQUENCE SIZE (1..MAX) OF
AccessDescription
AccessDescription ::= SEQUENCE {
accessMethod OBJECT IDENTIFIER,
accessLocation GeneralName }
-- CRL
number extension OID and syntax
id-ce-cRLNumber
OBJECT IDENTIFIER ::= { id-ce 20 }
CRLNumber
::= INTEGER (0..MAX)
--
issuing distribution point extension OID and syntax
id-ce-issuingDistributionPoint
OBJECT IDENTIFIER ::= { id-ce 28 }
IssuingDistributionPoint
::= SEQUENCE {
distributionPoint [0] DistributionPointName OPTIONAL,
onlyContainsUserCerts [1] BOOLEAN DEFAULT FALSE,
onlyContainsCACerts [2] BOOLEAN DEFAULT FALSE,
onlySomeReasons [3] ReasonFlags OPTIONAL,
indirectCRL [4] BOOLEAN DEFAULT FALSE }
id-ce-deltaCRLIndicator
OBJECT IDENTIFIER ::= { id-ce 27 }
--
deltaCRLIndicator ::= BaseCRLNumber
BaseCRLNumber
::= CRLNumber
-- CRL
reasons extension OID and syntax
id-ce-cRLReasons
OBJECT IDENTIFIER ::= { id-ce 21 }
CRLReason
::= ENUMERATED {
unspecified (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6),
removeFromCRL (8) }
--
certificate issuer CRL entry extension OID and syntax
Housley,
et. al. Standards Track [Page 89]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
id-ce-certificateIssuer
OBJECT IDENTIFIER ::= { id-ce 29 }
CertificateIssuer
::= GeneralNames
-- hold
instruction extension OID and syntax
id-ce-holdInstructionCode
OBJECT IDENTIFIER ::= { id-ce 23 }
HoldInstructionCode
::= OBJECT IDENTIFIER
-- ANSI
x9 holdinstructions
-- ANSI
x9 arc holdinstruction arc
holdInstruction
OBJECT IDENTIFIER ::=
{joint-iso-itu-t(2) member-body(2)
us(840) x9cm(10040) 2}
-- ANSI
X9 holdinstructions referenced by this standard
id-holdinstruction-none
OBJECT IDENTIFIER ::=
{holdInstruction 1} -- deprecated
id-holdinstruction-callissuer
OBJECT IDENTIFIER ::=
{holdInstruction 2}
id-holdinstruction-reject
OBJECT IDENTIFIER ::=
{holdInstruction 3}
--
invalidity date CRL entry extension OID and syntax
id-ce-invalidityDate
OBJECT IDENTIFIER ::= { id-ce 24 }
InvalidityDate
::= GeneralizedTime
END
Housley,
et. al. Standards Track [Page 90]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
Appendix
B. 1993 ASN.1 Structures and OIDs
B.1
Explicitly Tagged Module, 1993 Syntax
PKIX1Explicit93
{iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0)
id-pkix1-explicit-93(3)}
DEFINITIONS
EXPLICIT TAGS ::=
BEGIN
--
EXPORTS ALL --
IMPORTS
authorityKeyIdentifier,
subjectKeyIdentifier, keyUsage,
extendedKeyUsage,
privateKeyUsagePeriod, certificatePolicies,
policyMappings, subjectAltName,
issuerAltName,
basicConstraints, nameConstraints,
policyConstraints,
cRLDistributionPoints,
subjectDirectoryAttributes,
cRLNumber, reasonCode,
instructionCode, invalidityDate,
issuingDistributionPoint,
certificateIssuer,
deltaCRLIndicator,
authorityInfoAccess, id-ce
FROM PKIX1Implicit93 {iso(1)
identified-organization(3)
dod(6) internet(1) security(5)
mechanisms(5) pkix(7)
id-mod(0) id-pkix1-implicit-93(4)}
;
--
-- Locally defined OIDs --
id-pkix OBJECT IDENTIFIER ::=
{ iso(1) identified-organization(3)
dod(6) internet(1)
security(5) mechanisms(5)
pkix(7) }
-- PKIX
arcs
-- arc
for private certificate extensions
id-pe
OBJECT IDENTIFIER ::= { id-pkix 1 }
-- arc for policy qualifier types
id-qt
OBJECT IDENTIFIER ::= { id-pkix 2 }
-- arc
for extended key purpose OIDS
id-kp
OBJECT IDENTIFIER ::= { id-pkix 3 }
-- arc
for access descriptors
id-ad
OBJECT IDENTIFIER ::= { id-pkix 48 }
--
policyQualifierIds for Internet policy qualifiers
id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
-- OID for CPS qualifier
Housley,
et. al. Standards Track [Page 91]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
-- OID for user notice qualifier
--
based on excerpts from AuthenticationFramework
-- {joint-iso-ccitt ds(5) modules(1)
authenticationFramework(7) 2}
-- Public Key Certificate --
Certificate ::= SIGNED { SEQUENCE {
version [0]
Version DEFAULT v1,
serialNumber CertificateSerialNumber,
signature AlgorithmIdentifier,
issuer Name,
validity Validity,
subject Name,
subjectPublicKeyInfo SubjectPublicKeyInfo,
issuerUniqueIdentifier [1]
IMPLICIT UniqueIdentifier OPTIONAL,
---if present,
version shall be v2 or v3--
subjectUniqueIdentifier [2] IMPLICIT UniqueIdentifier OPTIONAL,
---if present,
version shall be v2 or v3--
extensions [3]
Extensions OPTIONAL
--if present,
version shall be v3--} }
UniqueIdentifier ::=
BIT STRING
Version ::= INTEGER { v1(0), v2(1), v3(2) }
CertificateSerialNumber
::= INTEGER
Validity ::= SEQUENCE {
notBefore Time,
notAfter Time }
Time
::= CHOICE {
utcTime UTCTime,
generalTime GeneralizedTime }
SubjectPublicKeyInfo ::=
SEQUENCE{
algorithm AlgorithmIdentifier,
subjectPublicKey BIT STRING}
Extensions ::=
SEQUENCE SIZE (1..MAX) OF Extension
Extension ::=
SEQUENCE {
extnId EXTENSION.&id ({ExtensionSet}),
critical BOOLEAN DEFAULT FALSE,
extnValue OCTET STRING }
-- contains a DER encoding of
a value of type
Housley,
et. al. Standards Track [Page 92]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
-- &ExtnType for the
-- extension object identified
by extnId --
-- The
following information object set is defined to constrain the
-- set
of legal certificate extensions.
ExtensionSet EXTENSION ::= {
authorityKeyIdentifier |
subjectKeyIdentifier |
keyUsage |
extendedKeyUsage |
privateKeyUsagePeriod |
certificatePolicies |
policyMappings |
subjectAltName |
issuerAltName |
basicConstraints |
nameConstraints |
policyConstraints |
cRLDistributionPoints |
subjectDirectoryAttributes |
authorityInfoAccess }
EXTENSION ::=
CLASS {
&id OBJECT IDENTIFIER UNIQUE,
&ExtnType }
WITH
SYNTAX {
SYNTAX &ExtnType
IDENTIFIED BY &id }
-- Certificate Revocation
List --
CertificateList
::= SIGNED { SEQUENCE {
version Version OPTIONAL,
-- if present, shall be v2
signature AlgorithmIdentifier,
issuer Name,
thisUpdate Time,
nextUpdate Time OPTIONAL,
revokedCertificates SEQUENCE OF SEQUENCE {
userCertificate CertificateSerialNumber,
revocationDate Time,
crlEntryExtensions EntryExtensions OPTIONAL } OPTIONAL,
crlExtensions [0]
CRLExtensions OPTIONAL }}
CRLExtensions ::= SEQUENCE SIZE (1..MAX) OF CRLExtension
CRLExtension ::= SEQUENCE {
extnId EXTENSION.&id ({CRLExtensionSet}),
critical BOOLEAN DEFAULT FALSE,
Housley,
et. al. Standards Track [Page 93]
RFC
2459 Internet X.509 Public Key Infrastructure January 1999
extnValue OCTET STRING }
-- contains a DER encoding of
a value of type
-- &ExtnType for the
-- extension object identified
by extnId --
-- The
following information object set is defined to constrain the
-- set
of legal CRL extensions.
CRLExtensionSet
EXTENSION ::= { authorityKeyIdentifier |
issuerAltName |
cRLNumber |
deltaCRLIndicator |
issuingDistributionPoint }
--
EXTENSION defined above for certificates
EntryExtensions ::= SEQUENCE SIZE (1..MAX) OF EntryExtension
EntryExtension ::= SEQUENCE {
extnId EXTENSION.&id ({EntryExtensionSet}),
critical BOOLEAN DEFAULT FALSE,
extnValue OCTET STRING }
-- contains a DER encoding of
a value of type
-- &ExtnType for the
-- extension object identified
by extnId --
-- The
following information object set is defined to constrain the
-- set
of legal CRL entry extensions.
EntryExtensionSet
EXTENSION ::=
{ reasonCode |
instructionCode |
invalidityDate |
certificateIssuer }
-- information object classes used in the defintion --
-- of certificates and
CRLs --
--
Parameterized Type SIGNED --
SIGNED { ToBeSigned } ::= SEQUENCE {
toBeSigned ToBeSigned,
algorithm AlgorithmIdentifier,
signature BIT STRING
}
--
Definition of AlgorithmIdentifier
-- ISO
definition was:
--
Housley,
et. al. Standards Track [Page 94]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
--
AlgorithmIdentifier ::= SEQUENCE {
-- algorithm ALGORITHM.&id({SupportedAlgorithms}),
-- parameters ALGORITHM.&Type({SupportedAlgorithms}
-- {
@algorithm}) OPTIONAL }
--
Definition of ALGORITHM
--
ALGORITHM ::= TYPE-IDENTIFIER
-- The
following PKIX definition replaces the X.509 definition
--
AlgorithmIdentifier ::=
SEQUENCE {
algorithm ALGORITHM-ID.&id({SupportedAlgorithms}),
parameters ALGORITHM-ID.&Type({SupportedAlgorithms}
{
@algorithm}) OPTIONAL }
--
Definition of ALGORITHM-ID
ALGORITHM-ID ::= CLASS {
&id OBJECT IDENTIFIER UNIQUE,
&Type OPTIONAL
}
WITH SYNTAX { OID &id [PARMS
&Type] }
-- The
definition of SupportedAlgorithms may be modified as this
--
document does not specify a mandatory algorithm set. In addition,
-- the
set is specified as extensible, since additional algorithms
-- may
be supported
SupportedAlgorithms ALGORITHM-ID ::= { ..., --
extensible
rsaPublicKey |
rsaSHA-1 |
rsaMD5 |
rsaMD2 |
dssPublicKey |
dsaSHA-1 |
dhPublicKey }
-- OIDs
and parameter structures for ALGORITHM-IDs used
-- in
this specification
rsaPublicKey
ALGORITHM-ID ::= { OID rsaEncryption PARMS NULL }
rsaSHA-1
ALGORITHM-ID ::= { OID sha1WithRSAEncryption PARMS NULL }
rsaMD5
ALGORITHM-ID ::= { OID md5WithRSAEncryption PARMS NULL }
rsaMD2
ALGORITHM-ID ::= { OID md2WithRSAEncryption PARMS NULL }
Housley,
et. al. Standards Track [Page 95]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
dssPublicKey
ALGORITHM-ID ::= { OID id-dsa PARMS Dss-Parms }
dsaSHA-1
ALGORITHM-ID ::= { OID id-dsa-with-sha1 }
dhPublicKey
ALGORITHM-ID ::= {OID dhpublicnumber PARMS DomainParameters}
--
algorithm identifiers and parameter structures
pkcs-1
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) 1 }
rsaEncryption
OBJECT IDENTIFIER ::= { pkcs-1 1 }
md2WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 2 }
md5WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 4 }
sha1WithRSAEncryption
OBJECT IDENTIFIER ::= { pkcs-1 5 }
id-dsa-with-sha1
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840) x9-57
(10040) x9algorithm(4) 3 }
Dss-Sig-Value ::=
SEQUENCE {
r
INTEGER,
s
INTEGER }
dhpublicnumber
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840)
ansi-x942(10046) number-type(2) 1 }
DomainParameters
::= SEQUENCE {
p
INTEGER, -- odd prime, p=jq +1
g
INTEGER, -- generator, g
q
INTEGER, -- factor of p-1
j
INTEGER OPTIONAL, -- subgroup factor, j>= 2
validationParms ValidationParms OPTIONAL }
ValidationParms
::= SEQUENCE {
seed BIT STRING,
pgenCounter INTEGER }
id-dsa
OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840)
x9-57(10040) x9algorithm(4) 1 }
Dss-Parms ::=
SEQUENCE {
p INTEGER,
q INTEGER,
g INTEGER }
Housley,
et. al. Standards Track [Page 96]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
-- The ASN.1 in this section supports the
Name type
-- and the directoryAttribute extension
--
attribute data types --
Attribute ::=
SEQUENCE {
type ATTRIBUTE.&id ({SupportedAttributes}),
values SET SIZE (1 .. MAX) OF ATTRIBUTE.&Type
({SupportedAttributes}{@type})}
AttributeTypeAndValue ::= SEQUENCE {
type ATTRIBUTE.&id ({SupportedAttributes}),
value ATTRIBUTE.&Type ({SupportedAttributes}{@type})}
--
naming data types --
Name ::= CHOICE { -- only one possibility for now --
rdnSequence RDNSequence }
RDNSequence
::= SEQUENCE OF RelativeDistinguishedName
RelativeDistinguishedName ::=
SET SIZE (1 .. MAX) OF
AttributeTypeAndValue
ID ::=
OBJECT IDENTIFIER
--
ATTRIBUTE information object class specification
-- Note: This has been greatly simplified for
PKIX !!
ATTRIBUTE ::= CLASS {
&Type,
&id OBJECT IDENTIFIER UNIQUE }
WITH
SYNTAX {
WITH SYNTAX &Type ID &id }
--
suggested naming attributes
-- Definition of the following information
object set may be
-- augmented to meet local requirements. Note that deleting
-- members of the set may prevent
interoperability with
-- conforming implementations.
SupportedAttributes ATTRIBUTE ::= {
name | commonName | surname |
givenName | initials |
generationQualifier |
dnQualifier | countryName |
localityName |
stateOrProvinceName | organizationName |
organizationalUnitName | title | pkcs9email }
name
ATTRIBUTE ::= {
Housley,
et. al. Standards Track [Page 97]
RFC
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WITH SYNTAX
DirectoryString { ub-name }
ID id-at-name }
commonName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-common-name}
ID id-at-commonName }
surname
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-name}
ID id-at-surname }
givenName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-name}
ID id-at-givenName }
initials
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-name}
ID id-at-initials }
generationQualifier
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-name}
ID id-at-generationQualifier}
dnQualifier
ATTRIBUTE ::= {
WITH SYNTAX PrintableString
ID id-at-dnQualifier }
countryName
ATTRIBUTE ::= {
WITH SYNTAX PrintableString (SIZE (2))
-- IS 3166 codes only
ID id-at-countryName }
localityName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-locality-name}
ID id-at-localityName }
stateOrProvinceName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-state-name}
ID id-at-stateOrProvinceName }
organizationName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-organization-name}
ID id-at-organizationName }
organizationalUnitName
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString {ub-organizational-unit-name}
ID id-at-organizationalUnitName }
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title
ATTRIBUTE ::= {
WITH SYNTAX DirectoryString
{ub-title}
ID id-at-title }
-- Legacy attributes
pkcs9email
ATTRIBUTE ::= {
WITH SYNTAX PHGString,
ID emailAddress }
PHGString
::= IA5String (SIZE(1..ub-emailaddress-length))
pkcs-9
OBJECT IDENTIFIER ::=
{ iso(1) member-body(2) us(840)
rsadsi(113549) pkcs(1) 9 }
emailAddress
OBJECT IDENTIFIER ::= { pkcs-9 1 }
-- object identifiers for Name type and
directory attribute support
--
Object identifier assignments --
id-at OBJECT IDENTIFIER ::=
{joint-iso-ccitt(2) ds(5) 4}
--
Attributes --
id-at-commonName OBJECT IDENTIFIER ::=
{id-at 3}
id-at-surname OBJECT IDENTIFIER ::= {id-at 4}
id-at-countryName OBJECT IDENTIFIER ::=
{id-at 6}
id-at-localityName OBJECT IDENTIFIER ::=
{id-at 7}
id-at-stateOrProvinceName OBJECT IDENTIFIER ::= {id-at 8}
id-at-organizationName OBJECT IDENTIFIER ::= {id-at 10}
id-at-organizationalUnitName OBJECT IDENTIFIER ::= {id-at 11}
id-at-title OBJECT IDENTIFIER ::=
{id-at 12}
id-at-name OBJECT IDENTIFIER ::=
{id-at 41}
id-at-givenName OBJECT IDENTIFIER ::=
{id-at 42}
id-at-initials OBJECT IDENTIFIER ::=
{id-at 43}
id-at-generationQualifier OBJECT IDENTIFIER ::= {id-at 44}
id-at-dnQualifier OBJECT IDENTIFIER ::=
{id-at 46}
--
Directory string type, used extensively in Name types --
DirectoryString
{ INTEGER:maxSize } ::= CHOICE {
teletexString TeletexString (SIZE (1..maxSize)),
printableString PrintableString (SIZE (1..maxSize)),
universalString UniversalString (SIZE (1..maxSize)),
bmpString BMPString (SIZE(1..maxSize)),
utf8String UTF8String (SIZE(1..maxSize))
}
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-- End of ASN.1 for Name type and
directory attribute support --
-- The ASN.1 in this section supports
X.400 style names --
-- for implementations that use the
x400Address component --
-- of GeneralName. --
ORAddress
::= SEQUENCE {
built-in-standard-attributes
BuiltInStandardAttributes,
built-in-domain-defined-attributes
BuiltInDomainDefinedAttributes OPTIONAL,
-- see also
teletex-domain-defined-attributes
extension-attributes ExtensionAttributes
OPTIONAL }
-- The OR-address is semantically absent from
the OR-name if the
-- built-in-standard-attribute sequence is
empty and the
-- built-in-domain-defined-attributes and
extension-attributes are
-- both omitted.
-- Built-in Standard Attributes
BuiltInStandardAttributes
::= SEQUENCE {
country-name CountryName OPTIONAL,
administration-domain-name
AdministrationDomainName OPTIONAL,
network-address [0] NetworkAddress OPTIONAL,
-- see also extended-network-address
terminal-identifier [1] TerminalIdentifier OPTIONAL,
private-domain-name [2] PrivateDomainName OPTIONAL,
organization-name [3] OrganizationName OPTIONAL,
-- see also teletex-organization-name
numeric-user-identifier [4] NumericUserIdentifier OPTIONAL,
personal-name [5] PersonalName OPTIONAL,
-- see also teletex-personal-name
organizational-unit-names [6] OrganizationalUnitNames OPTIONAL
-- see also
teletex-organizational-unit-names -- }
CountryName
::= [APPLICATION 1] CHOICE {
x121-dcc-code NumericString
(SIZE (ub-country-name-numeric-length)),
iso-3166-alpha2-code PrintableString
(SIZE
(ub-country-name-alpha-length)) }
AdministrationDomainName
::= [APPLICATION 2] CHOICE {
numeric NumericString (SIZE
(0..ub-domain-name-length)),
printable PrintableString (SIZE
(0..ub-domain-name-length)) }
NetworkAddress
::= X121Address
-- see
also extended-network-address
Housley,
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RFC
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X121Address
::= NumericString (SIZE (1..ub-x121-address-length))
TerminalIdentifier
::= PrintableString (SIZE (1..ub-terminal-id-length))
PrivateDomainName
::= CHOICE {
numeric NumericString (SIZE (1..ub-domain-name-length)),
printable PrintableString (SIZE
(1..ub-domain-name-length)) }
OrganizationName
::= PrintableString
(SIZE
(1..ub-organization-name-length))
-- see
also teletex-organization-name
NumericUserIdentifier
::= NumericString
(SIZE
(1..ub-numeric-user-id-length))
PersonalName
::= SET {
surname
[0] PrintableString (SIZE (1..ub-surname-length)),
given-name [1] PrintableString
(SIZE (1..ub-given-name-length))
OPTIONAL,
initials
[2] PrintableString
(SIZE
(1..ub-initials-length)) OPTIONAL,
generation-qualifier [3] PrintableString
(SIZE
(1..ub-generation-qualifier-length)) OPTIONAL}
-- see
also teletex-personal-name
OrganizationalUnitNames
::= SEQUENCE SIZE (1..ub-organizational-units)
OF
OrganizationalUnitName
-- see
also teletex-organizational-unit-names
OrganizationalUnitName
::= PrintableString (SIZE
(1..ub-organizational-unit-name-length))
-- Built-in Domain-defined Attributes
BuiltInDomainDefinedAttributes
::= SEQUENCE SIZE
(1..ub-domain-defined-attributes) OF
BuiltInDomainDefinedAttribute
BuiltInDomainDefinedAttribute
::= SEQUENCE {
type PrintableString (SIZE
(1..ub-domain-defined-attribute-type-length)),
value PrintableString (SIZE
(1..ub-domain-defined-attribute-value-length))
}
-- Extension Attributes
ExtensionAttributes
::= SET SIZE (1..ub-extension-attributes)
OF
ExtensionAttribute
ExtensionAttribute
::= SEQUENCE {
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extension-attribute-type [0]
EXTENSION-ATTRIBUTE.&id
({ExtensionAttributeTable}),
extension-attribute-value [1]
EXTENSION-ATTRIBUTE.&Type
({ExtensionAttributeTable}
{@extension-attribute-type}) }
EXTENSION-ATTRIBUTE
::= CLASS {
&id INTEGER (0..ub-extension-attributes) UNIQUE,
&Type }
WITH
SYNTAX {&Type IDENTIFIED BY &id}
ExtensionAttributeTable
EXTENSION-ATTRIBUTE ::= {
common-name |
teletex-common-name |
teletex-organization-name |
teletex-personal-name |
teletex-organizational-unit-names |
teletex-domain-defined-attributes |
pds-name |
physical-delivery-country-name |
postal-code |
physical-delivery-office-name |
physical-delivery-office-number |
extension-OR-address-components |
physical-delivery-personal-name |
physical-delivery-organization-name |
extension-physical-delivery-address-components |
unformatted-postal-address |
street-address |
post-office-box-address |
poste-restante-address |
unique-postal-name |
local-postal-attributes |
extended-network-address |
terminal-type }
-- Extension Standard Attributes
common-name
EXTENSION-ATTRIBUTE ::= {CommonName IDENTIFIED BY 1}
CommonName
::= PrintableString (SIZE (1..ub-common-name-length))
teletex-common-name
EXTENSION-ATTRIBUTE ::=
{TeletexCommonName IDENTIFIED
BY 2}
TeletexCommonName
::= TeletexString (SIZE (1..ub-common-name-length))
teletex-organization-name
EXTENSION-ATTRIBUTE ::=
{TeletexOrganizationName
IDENTIFIED BY 3}
Housley,
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TeletexOrganizationName
::=
TeletexString (SIZE
(1..ub-organization-name-length))
teletex-personal-name
EXTENSION-ATTRIBUTE ::=
{TeletexPersonalName
IDENTIFIED BY 4}
TeletexPersonalName
::= SET {
surname [0] TeletexString (SIZE
(1..ub-surname-length)),
given-name [1] TeletexString
(SIZE
(1..ub-given-name-length)) OPTIONAL,
initials [2] TeletexString (SIZE
(1..ub-initials-length)) OPTIONAL,
generation-qualifier [3] TeletexString
(SIZE
(1..ub-generation-qualifier-length)) OPTIONAL }
teletex-organizational-unit-names
EXTENSION-ATTRIBUTE ::=
{TeletexOrganizationalUnitNames IDENTIFIED
BY 5}
TeletexOrganizationalUnitNames
::= SEQUENCE SIZE
(1..ub-organizational-units) OF
TeletexOrganizationalUnitName
TeletexOrganizationalUnitName
::= TeletexString
(SIZE
(1..ub-organizational-unit-name-length))
pds-name
EXTENSION-ATTRIBUTE ::= {PDSName IDENTIFIED BY 7}
PDSName
::= PrintableString (SIZE (1..ub-pds-name-length))
physical-delivery-country-name
EXTENSION-ATTRIBUTE ::=
{PhysicalDeliveryCountryName IDENTIFIED BY
8}
PhysicalDeliveryCountryName
::= CHOICE {
x121-dcc-code NumericString (SIZE
(ub-country-name-numeric-length)),
iso-3166-alpha2-code PrintableString
(SIZE
(ub-country-name-alpha-length)) }
postal-code
EXTENSION-ATTRIBUTE ::= {PostalCode IDENTIFIED BY 9}
PostalCode
::= CHOICE {
numeric-code NumericString (SIZE (1..ub-postal-code-length)),
printable-code PrintableString (SIZE
(1..ub-postal-code-length)) }
physical-delivery-office-name
EXTENSION-ATTRIBUTE ::=
{PhysicalDeliveryOfficeName IDENTIFIED BY 10}
PhysicalDeliveryOfficeName
::= PDSParameter
physical-delivery-office-number
EXTENSION-ATTRIBUTE ::=
{PhysicalDeliveryOfficeNumber IDENTIFIED BY
11}
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et. al. Standards Track [Page 103]
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Infrastructure January 1999
PhysicalDeliveryOfficeNumber
::= PDSParameter
extension-OR-address-components
EXTENSION-ATTRIBUTE ::=
{ExtensionORAddressComponents IDENTIFIED BY
12}
ExtensionORAddressComponents
::= PDSParameter
physical-delivery-personal-name
EXTENSION-ATTRIBUTE ::=
{PhysicalDeliveryPersonalName IDENTIFIED BY
13}
PhysicalDeliveryPersonalName
::= PDSParameter
physical-delivery-organization-name
EXTENSION-ATTRIBUTE ::=
{PhysicalDeliveryOrganizationName
IDENTIFIED BY 14}
PhysicalDeliveryOrganizationName
::= PDSParameter
extension-physical-delivery-address-components
EXTENSION-ATTRIBUTE ::=
{ExtensionPhysicalDeliveryAddressComponents
IDENTIFIED BY 15}
ExtensionPhysicalDeliveryAddressComponents
::= PDSParameter
unformatted-postal-address
EXTENSION-ATTRIBUTE ::=
{UnformattedPostalAddress IDENTIFIED BY 16}
UnformattedPostalAddress
::= SET {
printable-address SEQUENCE SIZE
(1..ub-pds-physical-address-lines) OF
PrintableString (SIZE
(1..ub-pds-parameter-length)) OPTIONAL,
teletex-string TeletexString (SIZE
(1..ub-unformatted-address-length)) OPTIONAL }
street-address
EXTENSION-ATTRIBUTE ::=
{StreetAddress IDENTIFIED BY
17}
StreetAddress
::= PDSParameter
post-office-box-address
EXTENSION-ATTRIBUTE ::=
{PostOfficeBoxAddress
IDENTIFIED BY 18}
PostOfficeBoxAddress
::= PDSParameter
poste-restante-address
EXTENSION-ATTRIBUTE ::=
{PosteRestanteAddress
IDENTIFIED BY 19}
PosteRestanteAddress
::= PDSParameter
unique-postal-name
EXTENSION-ATTRIBUTE ::=
{UniquePostalName IDENTIFIED
BY 20}
Housley,
et. al. Standards Track [Page 104]
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Infrastructure January 1999
UniquePostalName
::= PDSParameter
local-postal-attributes
EXTENSION-ATTRIBUTE ::=
{LocalPostalAttributes
IDENTIFIED BY 21}
LocalPostalAttributes
::= PDSParameter
PDSParameter
::= SET {
printable-string PrintableString
(SIZE(1..ub-pds-parameter-length))
OPTIONAL,
teletex-string TeletexString
(SIZE(1..ub-pds-parameter-length))
OPTIONAL }
extended-network-address
EXTENSION-ATTRIBUTE ::=
{ExtendedNetworkAddress
IDENTIFIED BY 22}
ExtendedNetworkAddress
::= CHOICE {
e163-4-address SEQUENCE {
number [0] NumericString
(SIZE
(1..ub-e163-4-number-length)),
sub-address [1] NumericString
(SIZE
(1..ub-e163-4-sub-address-length)) OPTIONAL},
psap-address [0] PresentationAddress }
PresentationAddress
::= SEQUENCE {
pSelector [0] EXPLICIT OCTET STRING OPTIONAL,
sSelector [1] EXPLICIT OCTET STRING OPTIONAL,
tSelector [2] EXPLICIT OCTET STRING OPTIONAL,
nAddresses [3] EXPLICIT SET SIZE (1..MAX) OF OCTET STRING}
terminal-type
EXTENSION-ATTRIBUTE ::= {TerminalType IDENTIFIED BY 23}
TerminalType
::= INTEGER {
telex (3),
teletex (4),
g3-facsimile (5),
g4-facsimile (6),
ia5-terminal (7),
videotex (8) } (0..ub-integer-options)
-- Extension Domain-defined Attributes
teletex-domain-defined-attributes
EXTENSION-ATTRIBUTE ::=
{TeletexDomainDefinedAttributes IDENTIFIED
BY 6}
TeletexDomainDefinedAttributes
::= SEQUENCE SIZE
(1..ub-domain-defined-attributes) OF
TeletexDomainDefinedAttribute
Housley,
et. al. Standards Track [Page 105]
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TeletexDomainDefinedAttribute
::= SEQUENCE {
type TeletexString
(SIZE
(1..ub-domain-defined-attribute-type-length)),
value TeletexString
(SIZE
(1..ub-domain-defined-attribute-value-length)) }
-- specifications of Upper Bounds
-- shall be regarded as mandatory
-- from Annex B of ITU-T X.411
-- Reference Definition of MTS Parameter Upper
Bounds
-- Upper Bounds
ub-name
INTEGER ::= 32768
ub-common-name INTEGER ::= 64
ub-locality-name INTEGER ::= 128
ub-state-name INTEGER ::= 128
ub-organization-name INTEGER ::= 64
ub-organizational-unit-name INTEGER ::= 64
ub-title INTEGER ::= 64
ub-match INTEGER ::= 128
ub-emailaddress-length
INTEGER ::= 128
ub-common-name-length
INTEGER ::= 64
ub-country-name-alpha-length
INTEGER ::= 2
ub-country-name-numeric-length
INTEGER ::= 3
ub-domain-defined-attributes
INTEGER ::= 4
ub-domain-defined-attribute-type-length
INTEGER ::= 8
ub-domain-defined-attribute-value-length
INTEGER ::= 128
ub-domain-name-length
INTEGER ::= 16
ub-extension-attributes
INTEGER ::= 256
ub-e163-4-number-length
INTEGER ::= 15
ub-e163-4-sub-address-length
INTEGER ::= 40
ub-generation-qualifier-length
INTEGER ::= 3
ub-given-name-length
INTEGER ::= 16
ub-initials-length
INTEGER ::= 5
ub-integer-options
INTEGER ::= 256
ub-numeric-user-id-length
INTEGER ::= 32
ub-organization-name-length
INTEGER ::= 64
ub-organizational-unit-name-length
INTEGER ::= 32
ub-organizational-units
INTEGER ::= 4
ub-pds-name-length
INTEGER ::= 16
ub-pds-parameter-length
INTEGER ::= 30
ub-pds-physical-address-lines
INTEGER ::= 6
ub-postal-code-length
INTEGER ::= 16
ub-surname-length
INTEGER ::= 40
ub-terminal-id-length
INTEGER ::= 24
ub-unformatted-address-length
INTEGER ::= 180
Housley,
et. al. Standards Track [Page 106]
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Infrastructure January 1999
ub-x121-address-length
INTEGER ::= 16
-- Note
- upper bounds on TeletexString are measured in characters.
-- A
significantly greater number of octets will be required to hold
-- such
a value. As a minimum, 16 octets, or
twice the specified upper
--
bound, whichever is the larger, should be allowed.
END
Housley,
et. al. Standards Track [Page 107]
RFC
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Infrastructure January 1999
B.2
Implicitly Tagged Module, 1993 Syntax
PKIX1Implicit93 {iso(1) identified-organization(3) dod(6)
internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0)
id-pkix1-implicit-93(4)}
DEFINITIONS
IMPLICIT TAGS::=
BEGIN
--EXPORTS
ALL --
IMPORTS
id-pe, id-qt, id-kp, id-ad,
id-qt-unotice,
ORAddress, Name,
RelativeDistinguishedName,
CertificateSerialNumber,
CertificateList,
AlgorithmIdentifier, ub-name,
DirectoryString,
Attribute, EXTENSION
FROM PKIX1Explicit93 {iso(1)
identified-organization(3)
dod(6) internet(1) security(5)
mechanisms(5) pkix(7)
id-mod(0)
id-pkix1-explicit-93(3)};
-- Key
and policy information extensions --
authorityKeyIdentifier
EXTENSION ::= {
SYNTAX AuthorityKeyIdentifier
IDENTIFIED BY id-ce-authorityKeyIdentifier }
AuthorityKeyIdentifier
::= SEQUENCE {
keyIdentifier [0] KeyIdentifier OPTIONAL,
authorityCertIssuer [1] GeneralNames OPTIONAL,
authorityCertSerialNumber [2] CertificateSerialNumber OPTIONAL }
( WITH COMPONENTS {..., authorityCertIssuer PRESENT,
authorityCertSerialNumber PRESENT} |
WITH COMPONENTS {..., authorityCertIssuer ABSENT,
authorityCertSerialNumber
ABSENT} )
KeyIdentifier
::= OCTET STRING
subjectKeyIdentifier
EXTENSION ::= {
SYNTAX SubjectKeyIdentifier
IDENTIFIED BY id-ce-subjectKeyIdentifier }
SubjectKeyIdentifier
::= KeyIdentifier
keyUsage
EXTENSION ::= {
SYNTAX KeyUsage
IDENTIFIED BY id-ce-keyUsage }
Housley,
et. al. Standards Track [Page 108]
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2459 Internet X.509 Public Key
Infrastructure January 1999
KeyUsage
::= BIT STRING {
digitalSignature (0),
nonRepudiation (1),
keyEncipherment (2),
dataEncipherment (3),
keyAgreement (4),
keyCertSign (5),
cRLSign (6),
encipherOnly (7),
decipherOnly (8) }
extendedKeyUsage
EXTENSION ::= {
SYNTAX SEQUENCE SIZE (1..MAX) OF
KeyPurposeId
IDENTIFIED BY id-ce-extKeyUsage }
KeyPurposeId
::= OBJECT IDENTIFIER
-- PKIX-defined
extended key purpose OIDs
id-kp-serverAuth OBJECT IDENTIFIER ::= { id-kp 1 }
id-kp-clientAuth OBJECT IDENTIFIER ::= { id-kp 2 }
id-kp-codeSigning OBJECT IDENTIFIER ::= { id-kp 3 }
id-kp-emailProtection
OBJECT IDENTIFIER ::= { id-kp 4 }
id-kp-ipsecEndSystem OBJECT IDENTIFIER ::= { id-kp 5 }
id-kp-ipsecTunnel OBJECT IDENTIFIER ::= { id-kp 6 }
id-kp-ipsecUser OBJECT IDENTIFIER ::= { id-kp 7 }
id-kp-timeStamping OBJECT IDENTIFIER ::= { id-kp 8 }
privateKeyUsagePeriod
EXTENSION ::= {
SYNTAX PrivateKeyUsagePeriod
IDENTIFIED BY {
id-ce-privateKeyUsagePeriod } }
PrivateKeyUsagePeriod
::= SEQUENCE {
notBefore [0]
GeneralizedTime OPTIONAL,
notAfter [1] GeneralizedTime
OPTIONAL }
( WITH COMPONENTS {..., notBefore PRESENT} |
WITH COMPONENTS {..., notAfter PRESENT} )
certificatePolicies
EXTENSION ::= {
SYNTAX CertificatePoliciesSyntax
IDENTIFIED BY id-ce-certificatePolicies
}
CertificatePoliciesSyntax
::=
SEQUENCE SIZE (1..MAX) OF
PolicyInformation
PolicyInformation
::= SEQUENCE {
policyIdentifier CertPolicyId,
policyQualifiers SEQUENCE SIZE (1..MAX) OF
PolicyQualifierInfo OPTIONAL }
Housley,
et. al. Standards Track [Page 109]
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Infrastructure January 1999
CertPolicyId
::= OBJECT IDENTIFIER
PolicyQualifierInfo
::= SEQUENCE {
policyQualifierId CERT-POLICY-QUALIFIER.&id
({SupportedPolicyQualifiers}),
qualifier CERT-POLICY-QUALIFIER.&Qualifier
({SupportedPolicyQualifiers}
{@policyQualifierId})OPTIONAL }
SupportedPolicyQualifiers
CERT-POLICY-QUALIFIER ::= { noticeToUser |
pointerToCPS }
CERT-POLICY-QUALIFIER
::= CLASS {
&id OBJECT IDENTIFIER UNIQUE,
&Qualifier OPTIONAL }
WITH
SYNTAX {
POLICY-QUALIFIER-ID &id
[QUALIFIER-TYPE &Qualifier] }
policyMappings
EXTENSION ::= {
SYNTAX PolicyMappingsSyntax
IDENTIFIED BY id-ce-policyMappings }
PolicyMappingsSyntax
::= SEQUENCE SIZE (1..MAX) OF SEQUENCE {
issuerDomainPolicy CertPolicyId,
subjectDomainPolicy CertPolicyId }
--
Certificate subject and certificate issuer attributes extensions --
subjectAltName
EXTENSION ::= {
SYNTAX GeneralNames
IDENTIFIED BY id-ce-subjectAltName }
GeneralNames
::= SEQUENCE SIZE (1..MAX) OF GeneralName
GeneralName
::= CHOICE {
otherName [0]
INSTANCE OF OTHER-NAME,
rfc822Name [1] IA5String,
dNSName [2] IA5String,
x400Address [3] ORAddress,
directoryName [4] Name,
ediPartyName [5] EDIPartyName,
uniformResourceIdentifier [6] IA5String,
iPAddress [7] OCTET STRING,
registeredID [8] OBJECT IDENTIFIER }
OTHER-NAME
::= TYPE-IDENTIFIER
Housley,
et. al. Standards Track [Page 110]
RFC
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Infrastructure January 1999
EDIPartyName
::= SEQUENCE {
nameAssigner [0] DirectoryString {ub-name} OPTIONAL,
partyName [1]
DirectoryString {ub-name} }
issuerAltName
EXTENSION ::= {
SYNTAX GeneralNames
IDENTIFIED BY id-ce-issuerAltName }
subjectDirectoryAttributes
EXTENSION ::= {
SYNTAX AttributesSyntax
IDENTIFIED BY
id-ce-subjectDirectoryAttributes }
AttributesSyntax
::= SEQUENCE SIZE (1..MAX) OF Attribute
--
Certification path constraints extensions --
basicConstraints
EXTENSION ::= {
SYNTAX BasicConstraintsSyntax
IDENTIFIED BY id-ce-basicConstraints }
BasicConstraintsSyntax
::= SEQUENCE {
cA BOOLEAN DEFAULT FALSE,
pathLenConstraint INTEGER (0..MAX) OPTIONAL }
nameConstraints
EXTENSION ::= {
SYNTAX NameConstraintsSyntax
IDENTIFIED BY id-ce-nameConstraints }
NameConstraintsSyntax
::= SEQUENCE {
permittedSubtrees [0]
GeneralSubtrees OPTIONAL,
excludedSubtrees [1] GeneralSubtrees OPTIONAL }
GeneralSubtrees
::= SEQUENCE SIZE (1..MAX) OF GeneralSubtree
GeneralSubtree
::= SEQUENCE {
base GeneralName,
minimum [0]
BaseDistance DEFAULT 0,
maximum [1]
BaseDistance OPTIONAL }
BaseDistance
::= INTEGER (0..MAX)
policyConstraints
EXTENSION ::= {
SYNTAX PolicyConstraintsSyntax
IDENTIFIED BY id-ce-policyConstraints
}
PolicyConstraintsSyntax
::= SEQUENCE {
requireExplicitPolicy [0] SkipCerts OPTIONAL,
inhibitPolicyMapping [1] SkipCerts OPTIONAL }
Housley,
et. al. Standards Track [Page 111]
RFC
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Infrastructure January 1999
SkipCerts
::= INTEGER (0..MAX)
--
Basic CRL extensions --
cRLNumber
EXTENSION ::= {
SYNTAX CRLNumber
IDENTIFIED BY id-ce-cRLNumber }
CRLNumber
::= INTEGER (0..MAX)
reasonCode
EXTENSION ::= {
SYNTAX CRLReason
IDENTIFIED BY id-ce-reasonCode }
CRLReason
::= ENUMERATED {
unspecified (0),
keyCompromise (1),
cACompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6),
removeFromCRL (8) }
instructionCode
EXTENSION ::= {
SYNTAX HoldInstruction
IDENTIFIED BY id-ce-instructionCode }
HoldInstruction
::= OBJECT IDENTIFIER
--
holdinstructions described in this specification, from ANSI x9
-- ANSI
x9 arc holdinstruction arc
holdInstruction
OBJECT IDENTIFIER ::= {
joint-iso-ccitt(2) member-body(2) us(840)
x9cm(10040) 2}
-- ANSI
X9 holdinstructions referenced by this standard
id-holdinstruction-none
OBJECT IDENTIFIER ::= {holdInstruction 1}
id-holdinstruction-callissuer
OBJECT IDENTIFIER ::= {holdInstruction 2}
id-holdinstruction-reject
OBJECT IDENTIFIER ::= {holdInstruction 3}
invalidityDate
EXTENSION ::= {
SYNTAX GeneralizedTime
IDENTIFIED BY id-ce-invalidityDate }
-- CRL
distribution points and delta-CRL extensions --
cRLDistributionPoints
EXTENSION ::= {
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Infrastructure January 1999
SYNTAX CRLDistPointsSyntax
IDENTIFIED BY
id-ce-cRLDistributionPoints }
CRLDistPointsSyntax
::= SEQUENCE SIZE (1..MAX) OF DistributionPoint
DistributionPoint
::= SEQUENCE {
distributionPoint [0]
DistributionPointName OPTIONAL,
reasons [1] ReasonFlags
OPTIONAL,
cRLIssuer [2]
GeneralNames OPTIONAL }
DistributionPointName
::= CHOICE {
fullName [0]
GeneralNames,
nameRelativeToCRLIssuer [1] RelativeDistinguishedName }
ReasonFlags
::= BIT STRING {
unused (0),
keyCompromise (1),
caCompromise (2),
affiliationChanged (3),
superseded (4),
cessationOfOperation (5),
certificateHold (6) }
issuingDistributionPoint
EXTENSION ::= {
SYNTAX IssuingDistPointSyntax
IDENTIFIED BY
id-ce-issuingDistributionPoint }
IssuingDistPointSyntax
::= SEQUENCE {
distributionPoint [0] DistributionPointName OPTIONAL,
onlyContainsUserCerts [1] BOOLEAN DEFAULT FALSE,
onlyContainsCACerts [2] BOOLEAN DEFAULT FALSE,
onlySomeReasons [3] ReasonFlags OPTIONAL,
indirectCRL [4] BOOLEAN DEFAULT FALSE }
certificateIssuer
EXTENSION ::= {
SYNTAX GeneralNames
IDENTIFIED BY id-ce-certificateIssuer
}
deltaCRLIndicator
EXTENSION ::= {
SYNTAX BaseCRLNumber
IDENTIFIED BY id-ce-deltaCRLIndicator
}
BaseCRLNumber
::= CRLNumber
--
Object identifier assignments for ISO certificate extensions --
id-ce OBJECT IDENTIFIER ::=
{joint-iso-ccitt(2) ds(5) 29}
id-ce-subjectDirectoryAttributes OBJECT IDENTIFIER ::= {id-ce 9}
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id-ce-subjectKeyIdentifier OBJECT IDENTIFIER ::= {id-ce 14}
id-ce-keyUsage OBJECT IDENTIFIER ::=
{id-ce 15}
id-ce-privateKeyUsagePeriod OBJECT IDENTIFIER ::= {id-ce 16}
id-ce-subjectAltName OBJECT IDENTIFIER ::= {id-ce 17}
id-ce-issuerAltName OBJECT IDENTIFIER ::= {id-ce
18}
id-ce-basicConstraints OBJECT IDENTIFIER ::= {id-ce 19}
id-ce-cRLNumber OBJECT IDENTIFIER ::=
{id-ce 20}
id-ce-reasonCode OBJECT IDENTIFIER ::=
{id-ce 21}
id-ce-instructionCode OBJECT IDENTIFIER ::= {id-ce 23}
id-ce-invalidityDate OBJECT IDENTIFIER ::= {id-ce
24}
id-ce-deltaCRLIndicator OBJECT IDENTIFIER ::= {id-ce 27}
id-ce-issuingDistributionPoint OBJECT IDENTIFIER ::= {id-ce 28}
id-ce-certificateIssuer OBJECT IDENTIFIER ::= {id-ce 29}
id-ce-nameConstraints OBJECT IDENTIFIER ::= {id-ce 30}
id-ce-cRLDistributionPoints OBJECT IDENTIFIER ::= {id-ce 31}
id-ce-certificatePolicies OBJECT IDENTIFIER ::= {id-ce 32}
id-ce-policyMappings OBJECT IDENTIFIER ::= {id-ce
33}
id-ce-policyConstraints OBJECT IDENTIFIER ::= {id-ce 36}
id-ce-authorityKeyIdentifier OBJECT IDENTIFIER ::= {id-ce 35}
id-ce-extKeyUsage OBJECT IDENTIFIER ::= {id-ce
37}
-- PKIX
1 extensions
authorityInfoAccess
EXTENSION ::= {
SYNTAX AuthorityInfoAccessSyntax
IDENTIFIED BY
id-pe-authorityInfoAccess }
AuthorityInfoAccessSyntax ::=
SEQUENCE SIZE (1..MAX) OF
AccessDescription
AccessDescription ::=
SEQUENCE {
accessMethod OBJECT IDENTIFIER,
accessLocation GeneralName }
id-pe-authorityInfoAccess
OBJECT IDENTIFIER ::= { id-pe 1 }
id-ad-ocsp OBJECT IDENTIFIER ::= { id-ad 1 }
id-ad-caIssuers
OBJECT IDENTIFIER ::= { id-ad 2 }
-- PKIX
policy qualifier definitions
noticeToUser
CERT-POLICY-QUALIFIER ::= {
POLICY-QUALIFIER-ID id-qt-cps QUALIFIER-TYPE CPSuri}
pointerToCPS
CERT-POLICY-QUALIFIER ::= {
POLICY-QUALIFIER-ID id-qt-unotice QUALIFIER-TYPE UserNotice}
id-qt-cps OBJECT IDENTIFIER ::= { id-qt 1 }
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id-qt-unotice OBJECT IDENTIFIER ::= { id-qt 2 }
CPSuri
::= IA5String
UserNotice
::= SEQUENCE {
noticeRef NoticeReference OPTIONAL,
explicitText DisplayText OPTIONAL}
NoticeReference
::= SEQUENCE {
organization DisplayText,
noticeNumbers SEQUENCE OF INTEGER }
DisplayText
::= CHOICE {
visibleString VisibleString (SIZE
(1..200)),
bmpString BMPString (SIZE
(1..200)),
utf8String UTF8String (SIZE
(1..200)) }
END
Housley,
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Appendix
C. ASN.1 Notes
The construct "SEQUENCE SIZE (1..MAX)
OF" appears in several ASN.1
constructs. A valid ASN.1 sequence will
have zero or more entries.
The SIZE (1..MAX) construct constrains the
sequence to have at least
one entry. MAX indicates the upper bound is
unspecified.
Implementations are free to choose an upper
bound that suits their
environment.
The construct "positiveInt ::= INTEGER
(0..MAX)" defines positiveInt
as a subtype of INTEGER containing integers
greater than or equal to
zero.
The upper bound is unspecified. Implementations are free to
select an upper bound that suits their
environment.
The character string type PrintableString supports
a very basic Latin
character set: the lower case letters 'a' through 'z', upper case
letters 'A' through 'Z', the digits '0'
through '9', eleven special
characters ' " ( ) + , - . / : ? and
space.
The character string type TeletexString is
a superset of
PrintableString. TeletexString supports a fairly standard (ascii-
like) Latin character set, Latin characters
with non-spacing accents
and Japanese characters.
The character string type UniversalString
supports any of the
characters allowed by ISO 10646-1. ISO
10646 is the Universal
multiple-octet coded Character Set
(UCS). ISO 10646-1 specifes the
architecture and the "basic
multilingual plane" - a large standard
character set which includes all major
world character standards.
The character string type UTF8String will
be introduced in the 1998
version of ASN.1. UTF8String is a universal type and has been
assigned tag number 12. The content of UTF8String was defined by RFC
2044 and updated in RFC 2279, "UTF-8,
a transformation Format of ISP
10646." ISO is expected to formally add UTF8String to the list of
choices for DirectoryString in 1998 as
well.
In anticipation of these changes, and in
conformance with IETF Best
Practices codified in RFC 2277, IETF Policy
on Character Sets and
Languages, this document includes
UTF8String as a choice in
DirectoryString and the CPS qualifier
extensions.
Housley,
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Infrastructure January 1999
Appendix
D. Examples
This section contains four examples: three
certificates and a CRL.
The first two certificates and the CRL
comprise a minimal
certification path.
Section D.1 contains an annotated hex dump
of a "self-signed"
certificate issued by a CA whose
distinguished name is
cn=us,o=gov,ou=nist. The certificate contains a DSA public key
with
parameters, and is signed by the
corresponding DSA private key.
Section D.2 contains an annotated hex dump
of an end-entity
certificate. The end entity certificate contains a DSA public key,
and is signed by the private key
corresponding to the "self-signed"
certificate in section D.1.
Section D.3 contains a dump of an end
entity certificate which
contains an RSA public key and is signed
with RSA and MD5. This
certificate is not part of the minimal
certification path.
Section D.4 contains an annotated hex dump
of a CRL. The CRL is
issued by the CA whose distinguished name
is cn=us,o=gov,ou=nist and
the list of revoked certificates includes
the end entity certificate
presented in D.2.
D.1
Certificate
This section contains an annotated hex dump
of a 699 byte version 3
certificate. The certificate contains the following information:
(a) the serial number is 17 (11 hex);
(b) the certificate is signed with DSA and
the SHA-1 hash algorithm;
(c) the issuer's distinguished name is
OU=nist; O=gov; C=US
(d) and the subject's distinguished name is
OU=nist; O=gov; C=US
(e) the certificate was issued on June 30,
1997 and will expire on
December 31, 1997;
(f) the certificate contains a 1024 bit DSA
public key with
parameters;
(g) the certificate contains a subject key
identifier extension; and
(h) the certificate is a CA certificate (as
indicated through the
basic constraints extension.)
0000 30
82 02 b7 695: SEQUENCE
0004 30
82 02 77 631: . SEQUENCE tbscertificate
0008 a0
03 3: . . [0]
0010 02
01 1: . . . INTEGER 2
: 02
0013 02
01 1: . . INTEGER 17
: 11
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0016 30
09 9: . . SEQUENCE
0018 06
07 7: . . . OID
1.2.840.10040.4.3: dsa-with-sha
: 2a 86 48 ce 38 04 03
0027 30
2a 42: . . SEQUENCE
0029 31
0b 11: . . . SET
0031 30
09 9: . . . . SEQUENCE
0033 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0038 13
02 2: . . . . .
PrintableString 'US'
: 55 53
0042 31
0c 12: . . . SET
0044 30
0a 10: . . . . SEQUENCE
0046 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0051 13
03 3: . . . . .
PrintableString 'gov'
: 67 6f 76
0056 31
0d 13: . . . SET
0058 30
0b 11: . . . . SEQUENCE
0060 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0065 13
04 4: . . . . .
PrintableString 'nist'
: 6e 69 73 74
0071 30
1e 30: . . SEQUENCE
0073 17
0d 13: . . . UTCTime '970630000000Z'
: 39 37 30 36 33 30 30 30
30 30 30 30 5a
0088 17
0d 13: . . . UTCTime '971231000000Z'
: 39 37 31 32 33 31 30 30
30 30 30 30 5a
0103 30
2a 42: . . SEQUENCE
0105 31
0b 11: . . . SET
0107 30
09 9: . . . . SEQUENCE
0109 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0114 13
02 2: . . . . .
PrintableString 'US'
: 55 53
0118 31
0c 12: . . . SET
0120 30
0a 10: . . . . SEQUENCE
0122 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0127 13
03 3: . . . . . PrintableString 'gov'
: 67 6f 76
0132 31
0d 13: . . . SET
0134 30
0b 11: . . . . SEQUENCE
0136 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0141 13
04 4: . . . . . PrintableString 'nist'
: 6e 69 73 74
0147 30
82 01 b4 436: . . SEQUENCE
0151 30
82 01 29 297: . . . SEQUENCE
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0155 06
07 7: . . . . OID
1.2.840.10040.4.1: dsa
: 2a 86 48 ce 38 04 01
0164 30
82 01 1c 284: . . . . SEQUENCE
0168 02
81 80 128: . . . . . INTEGER
: d4 38 02 c5 35 7b d5 0b
a1 7e 5d 72 59 63 55 d3
: 45 56 ea e2 25 1a 6b c5
a4 ab aa 0b d4 62 b4 d2
: 21 b1 95 a2 c6 01 c9 c3
fa 01 6f 79 86 83 3d 03
: 61 e1 f1 92 ac bc 03 4e
89 a3 c9 53 4a f7 e2 a6
: 48 cf 42 1e 21 b1 5c 2b 3a 7f ba be 6b 5a f7 0a
: 26 d8 8e 1b eb ec bf 1e
5a 3f 45 c0 bd 31 23 be
: 69 71 a7 c2 90 fe a5 d6
80 b5 24 dc 44 9c eb 4d
: f9 da f0 c8 e8 a2 4c 99
07 5c 8e 35 2b 7d 57 8d
0299 02
14 20: . . . . . INTEGER
: a7 83 9b f3 bd 2c 20 07
fc 4c e7 e8 9f f3 39 83
: 51 0d dc dd
0321 02
81 80 128: . . . . . INTEGER
: 0e 3b 46 31 8a 0a 58 86
40 84 e3 a1 22 0d 88 ca
: 90 88 57 64 9f 01 21 e0
15 05 94 24 82 e2 10 90
: d9 e1 4e 10 5c e7 54 6b
d4 0c 2b 1b 59 0a a0 b5
: a1 7d b5 07 e3 65 7c ea
90 d8 8e 30 42 e4 85 bb
: ac fa 4e 76 4b 78 0e df 6c e5 a6 e1 bd 59 77 7d
: a6 97 59 c5 29 a7 b3 3f
95 3e 9d f1 59 2d f7 42
: 87 62 3f f1 b8 6f c7 3d
4b b8 8d 74 c4 ca 44 90
: cf 67 db de 14 60 97 4a
d1 f7 6d 9e 09 94 c4 0d
0452 03
81 84 132: . . . BIT STRING (0 unused bits)
: 02 81 80 aa 98 ea 13 94
a2 db f1 5b 7f 98 2f 78
: e7 d8 e3 b9 71 86 f6 80
2f 40 39 c3 da 3b 4b 13
: 46 26 ee 0d 56 c5 a3 3a
39 b7 7d 33 c2 6b 5c 77
: 92 f2 55 65 90 39 cd 1a
3c 86 e1 32 eb 25 bc 91
: c4 ff 80 4f 36 61 bd cc
e2 61 04 e0 7e 60 13 ca
: c0 9c dd e0 ea 41 de 33
c1 f1 44 a9 bc 71 de cf
: 59 d4 6e da 44 99 3c 21
64 e4 78 54 9d d0 7b ba
: 4e f5 18 4d 5e 39 30 bf
e0 d1 f6 f4 83 25 4f 14
: aa 71 e1
0587 a3
32 50: . . [3]
0589 30
30 48: . . . SEQUENCE
0591 30
0f 9: . . . . SEQUENCE
0593 06
03 3: . . . . . OID 2.5.29.19:
basicConstraints
: 55 1d 13
0598 01
01 1: . . . . . TRUE
: ff
0601 04
05 5: . . . . . OCTET STRING
: 30 03 01 01 ff
0608 30
1d 29: . SEQUENCE
0610 06
03 3: . . . . . OID 2.5.29.14:
subjectKeyIdentifier
: 55 1d 0e
0615 04
16 22: . . . . . OCTET STRING
: 04 14 e7 26 c5 54 cd 5b
a3 6f 35 68 95 aa d5 ff
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: 1c 21 e4 22 75 d6
0639 30
09 9: . SEQUENCE
0641 06
07 7: . . OID
1.2.840.10040.4.3: dsa-with-sha
: 2a 86 48 ce 38 04 03
0650 03
2f 47: . BIT STRING (0 unused bits)
: 30 2c 02 14 a0 66 c1 76
33 99 13 51 8d 93 64 2f
: ca 13 73 de 79 1a 7d 33 02 14 5d 90 f6 ce 92 4a
: bf 29 11 24 80 28 a6 5a
8e 73 b6 76 02 68
D.2
Certificate
This section contains an annotated hex dump
of a 730 byte version 3
certificate. The certificate contains the following information:
(a) the serial number is 18 (12 hex);
(b) the certificate is signed with DSA and
the SHA-1 hash algorithm;
(c) the issuer's distinguished name is
OU=nist; O=gov; C=US
(d) and the subject's distinguished name is
CN=Tim Polk; OU=nist;
O=gov; C=US
(e) the certificate was valid from July 30,
1997 through December 1,
1997;
(f) the certificate contains a 1024 bit DSA
public key;
(g) the certificate is an end entity
certificate, as the basic
constraints extension is not present;
(h) the certificate contains an authority
key identifier extension;
and
(i) the certificate includes one
alternative name - an RFC 822
address.
0000 30
82 02 d6 726: SEQUENCE
0004 30
82 02 96 662: . SEQUENCE
0008 a0
03 3: . . [0]
0010 02
01 1: . . . INTEGER 2
: 02
0013 02
01 1: . . INTEGER 18
: 12
0016 30
09 9: . . SEQUENCE
0018 06
07 7: . . . OID 1.2.840.10040.4.3:
dsa-with-sha
: 2a 86 48 ce 38 04 03
0027 30
2a 42: . . SEQUENCE
0029 31
0b 11: . . . SET
0031 30
09 9: . . . . SEQUENCE
0033 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0038 13
02 2: . . . . .
PrintableString 'US'
: 55 53
0042 31
0c 12: . . . SET
0044 30
0a 10: . . . . SEQUENCE
0046 06
03 3: . . . . . OID 2.5.4.10: O
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RFC
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: 55 04 0a
0051 13
03 3: . . . . .
PrintableString 'gov'
: 67 6f 76
0056 31
0d 13: . . . SET
0058 30
0b 11: . . . . SEQUENCE
0060 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0065 13
04 4: . . . . .
PrintableString 'nist'
: 6e 69 73 74
0071 30
1e 30: . . SEQUENCE
0073 17
0d 13: . . . UTCTime '970730000000Z'
: 39 37 30 37 33 30 30 30
30 30 30 30 5a
0088 17
0d 13: . . . UTCTime '971201000000Z'
: 39 37 31 32 30 31 30 30
30 30 30 30 5a
0103 30
3d 61: . . SEQUENCE
0105 31
0b 11: . . . SET
0107 30
09 9: . . . . SEQUENCE
0109 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0114 13
02 2: . . . . .
PrintableString 'US'
: 55 53
0118 31
0c 12: . . . SET
0120 30
0a 10: . . . . SEQUENCE
0122 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0127 13
03 3: . . . . .
PrintableString 'gov'
: 67 6f 76
0132 31
0d 13: . . . SET
0134 30
0b 11: . . . . SEQUENCE
0136 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0141 13
04 4: . . . . .
PrintableString 'nist'
: 6e 69 73 74
0147 31
11 17: . . . SET
0149 30
0f 15: . . . . SEQUENCE
0151 06
03 3: . . . . . OID 2.5.4.3: CN
: 55 04 03
0156 13
08 8: . . . . .
PrintableString 'Tim Polk'
: 54 69 6d 20 50 6f 6c 6b
0166 30
82 01 b4 436: . . SEQUENCE
0170 30
82 01 29 297: . . . SEQUENCE
0174 06
07 7: . . . . OID
1.2.840.10040.4.1: dsa
: 2a 86 48 ce 38 04 01
0183 30
82 01 1c 284: . . . . SEQUENCE
0187 02
81 80 128: . . . . . INTEGER
: d4 38 02 c5 35 7b d5 0b
a1 7e 5d 72 59 63 55 d3
: 45 56 ea e2 25 1a 6b c5
a4 ab aa 0b d4 62 b4 d2
: 21 b1 95 a2 c6 01 c9 c3
fa 01 6f 79 86 83 3d 03
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: 61 e1 f1 92 ac bc 03 4e
89 a3 c9 53 4a f7 e2 a6
: 48 cf 42 1e 21 b1 5c 2b
3a 7f ba be 6b 5a f7 0a
: 26 d8 8e 1b eb ec bf 1e
5a 3f 45 c0 bd 31 23 be
: 69 71 a7 c2 90 fe a5 d6
80 b5 24 dc 44 9c eb 4d
: f9 da f0 c8 e8 a2 4c 99
07 5c 8e 35 2b 7d 57 8d
0318 02
14 20: . . . . . INTEGER
: a7 83 9b f3 bd 2c 20 07
fc 4c e7 e8 9f f3 39 83
: 51 0d dc dd
0340 02
81 80 128: . . . . . INTEGER
: 0e 3b 46 31 8a 0a 58 86
40 84 e3 a1 22 0d 88 ca
: 90 88 57 64 9f 01 21 e0
15 05 94 24 82 e2 10 90
: d9 e1 4e 10 5c e7 54 6b
d4 0c 2b 1b 59 0a a0 b5
: a1 7d b5 07 e3 65 7c ea
90 d8 8e 30 42 e4 85 bb
: ac fa 4e 76 4b 78 0e df
6c e5 a6 e1 bd 59 77 7d
: a6 97 59 c5 29 a7 b3 3f
95 3e 9d f1 59 2d f7 42
: 87 62 3f f1 b8 6f c7 3d
4b b8 8d 74 c4 ca 44 90
: cf 67 db de 14 60 97 4a
d1 f7 6d 9e 09 94 c4 0d
0471 03
81 84 132: . . . BIT STRING (0 unused bits)
: 02 81 80 a8 63 b1 60 70
94 7e 0b 86 08 93 0c 0d
: 08 12 4a 58 a9 af 9a 09
38 54 3b 46 82 fb 85 0d
: 18 8b 2a 77 f7 58 e8 f0
1d d2 18 df fe e7 e9 35
: c8 a6 1a db 8d 3d 3d f8
73 14 a9 0b 39 c7 95 f6
: 52 7d 2d 13 8c ae 03 29
3c 4e 8c b0 26 18 b6 d8
: 11 1f d4 12 0c 13 ce 3f
f1 c7 05 4e df e1 fc 44
: fd 25 34 19 4a 81 0d dd 98 42 ac d3 b6 91 0c 7f
: 16 72 a3 a0 8a d7 01 7f
fb 9c 93 e8 99 92 c8 42
: 47 c6 43
0606 a3
3e 62: . . [3]
0608 30
3c 60: . . . SEQUENCE
0610 30
19 25: . . . . SEQUENCE
0612 06
03 3: . . . . . OID 2.5.29.17:
subjectAltName
: 55 1d 11
0617 04
12 18: . . . . . OCTET STRING
: 30 10 81 0e 77 70 6f 6c
6b 40 6e 69 73 74 2e 67
: 6f 76
0637 30
1f 31: . . . . SEQUENCE
0639 06
03 3: . . . . . OID 2.5.29.35:
subjectAltName
: 55 1d 23
0644 04
18 24: . . . . . OCTET STRING
: 30 16 80 14 e7 26 c5 54
cd 5b a3 6f 35 68 95 aa
: d5 ff 1c 21 e4 22 75 d6
0670 30
09 9: . SEQUENCE
0672 06
07 7: . . OID
1.2.840.10040.4.3: dsa-with-sha
: 2a 86 48 ce 38 04 03
0681 03
2f 47: . BIT STRING (0 unused bits)
: 30 2c 02 14 3c 02 e0 ab
d9 5d 05 77 75 15 71 58
: 92 29 48 c4 1c 54 df fc
02 14 5b da 53 98 7f c5
: 33 df c6 09 b2 7a e3 6f
97 70 1e 14 ed 94
Housley,
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Infrastructure January 1999
D.3
End-Entity Certificate Using RSA
This section contains an annotated hex dump
of a 675 byte version 3
certificate. The certificate contains the following information:
(a) the serial number is 256;
(b) the certificate is signed with RSA and
the MD2 hash algorithm;
(c) the issuer's distinguished name is
OU=Dept. Arquitectura de
Computadors; O=Universitat Politecnica de
Catalunya; C=ES
(d) and the subject's distinguished name is
CN=Francisco Jordan;
OU=Dept. Arquitectura de Computadors;
O=Universitat Politecnica de
Catalunya; C=ES
(e) the certificate was issued on May 21,
1996 and expired on May 21,
1997;
(f) the certificate contains a 768 bit RSA
public key;
(g) the certificate is an end entity
certificate (not a CA
certificate);
(h) the certificate includes an alternative
subject name and an
alternative issuer name - bothe are URLs;
(i) the certificate include an authority
key identifier and
certificate policies extensions; and
(j) the certificate includes a critical key
usage extension
specifying the public is intended for
generation of digital
signatures.
0000 30
80 : SEQUENCE (size undefined)
0002 30
82 02 40 576: . SEQUENCE
0006 a0
03 3: . . [0]
0008 02
01 1: . . . INTEGER 2
: 02
0011 02
02 2: . . INTEGER 256
: 01 00
0015 30
0d 13: . . SEQUENCE
0017 06
09 9: . . . OID
1.2.840.113549.1.1.2:
MD2WithRSAEncryption
: 2a 86 48 86 f7 0d 01 01
02
0028 05
00 0: . . . NULL
0030 30
68 88: . . SEQUENCE
0032 31
0b 11: . . . SET
0034 30
09 9: . . . . SEQUENCE
0036 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0041 13
02 2: . . . . .
PrintableString 'ES'
: 45 53
0045 31
2d 45: . . . SET
0047 30
2b 43: . . . . SEQUENCE
0049 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0054 13
24 36: . . . . . PrintableString
Housley,
et. al. Standards Track [Page 123]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
'Universitat Politecnica
de Catalunya'
: 55 6e 69 76 65 72 73 69
74 61 74 20 50 6f 6c 69
: 74 65 63 6e 69 63 61 20
64 65 20 43 61 74 61 6c
: 75 6e 79 61
0092 31
2a 42: . . . SET
0094 30
28 40: . . . . SEQUENCE
0096 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0101 13
21 33: . . . . . PrintableString
'OU=Dept. Arquitectura de
Computadors'
: 44 65 70 74 2e 20 41 72
71 75 69 74 65 63 74 75
: 72 61 20 64 65 20 43 6f
6d 70 75 74 61 64 6f 72
: 73
0136 30
1e 30: . . SEQUENCE
0138 17
0d 13: . . . UTCTime '960521095826Z'
: 39 36 30 37 32 32 31 37
33 38 30 32 5a
0153 17
0d 13: . . . UTCTime '979521095826Z'
: 39 37 30 37 32 32 31 37 33 38 30 32 5a
0168 30
81 83 112: . . SEQUENCE
0171 31
0b 11: . . . SET
0173 30
09 9: . . . . SEQUENCE
0175 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0180 13
02 2: . . . . .
PrintableString 'ES'
: 45 53
0184 31
2d 12: . . . SET
0186 30
2b 16: . . . . SEQUENCE
0188 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0193 13
24 36: . . . . . PrintableString
'Universitat Politecnica
de Catalunya'
: 55 6e 69 76 65 72 73 69
74 61 74 20 50 6f 6c 69
: 74 65 63 6e 69 63 61 20
64 65 20 43 61 74 61 6c
: 75 6e 79 61
0231 31
2a 42: . . . SET
0233 30
28 40: . . . . SEQUENCE
0235 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
0240 13
21 33: . . . . . PrintableString
'Dept. Arquitectura de
Computadors'
: 44 65 70 74 2e 20 41 72
71 75 69 74 65 63 74 75
: 72 61 20 64 65 20 43 6f
6d 70 75 74 61 64 6f 72
: 73
0275 31
19 22: . . . SET
0277 30
17 20: . . . . SEQUENCE
0279 06
03 3: . . . . . OID 2.5.4.3: CN
: 55 04 03
0284 13
10 16: . . . . . PrintableString
'Francisco Jordan'
Housley,
et. al. Standards Track [Page 124]
RFC 2459 Internet X.509 Public Key
Infrastructure January 1999
: 46 72 61 6e 63 69 73 63
6f 20 4a 6f 72 64 61 6e
0302 30
7c 2: . . SEQUENCE
0304 30
0d 13: . . . SEQUENCE
0306 06
09 9: . . . . OID
1.2.840.113549.1.1.1: RSAEncryption
: 2a 86 48 86 f7 0d 01 01
01
0317 05
00 0: . . . . NULL
0319 03
6b 107: . . . BIT STRING
: 00 (0 unused bits)
: 30 68 02 61 00 be aa 8b
77 54 a3 af ca 77 9f 2f
: b0 cf 43 88 ff a6 6d 79
55 5b 61 8c 68 ec 48 1e
: 8a 86 38 a4 fe 19 b8 62
17 1d 9d 0f 47 2c ff 63
: 8f 29 91 04 d1 52 bc 7f
67 b6 b2 8f 74 55 c1 33
: 21 6c 8f ab 01 95 24 c8 b2 73 93 9d 22 61 50 a9
: 35 fb 9d 57 50 32 ef 56
52 50 93 ab b1 88 94 78
: 56 15 c6 1c 8b 02 03 01
00 01
0428 a3
81 97 151: . . [3]
0431 30
3c 60: . . . SEQUENCE
0433 30
1f 31: . . . . SEQUENCE
0435 06
03 3: . . . . . OID 2.5.29.35:
authorityKeyIdentifier
: 55 1d 23
0440 04
14 22: . . . . . OCTET STRING
: 30 12 80 10 0e 6b 3a bf
04 ea 04 c3 0e 6b 3a bf
: 04 ea 04 c3
0464 30
19 25: . . . . SEQUENCE
0466 06
03 3: . . . . . OID 2.5.29.15:
keyUsage
: 55 1d 0f
0471 01
01 1: . . . . . TRUE
0474 04
04 4: . . . . . OCTET STRING
: 03 02 07 80
0480 30
19 25: . . . . SEQUENCE
0482 06
03 3: . . . . . OID 2.5.29.32:
certificatePolicies
: 55 1d 20
0487 04
21 33: . . . . . OCTET STRING
: 30 1f 30 1d 06 04 2a 84
80 00 30 15 30 07 06 05
: 2a 84 80 00 01 30 0a 06
05 2a 84 80 00 02 02 01
: 0a
0522 30
1c 28: . . . . SEQUENCE
0524 06
03 3: . . . . . OID 2.5.29.17:
subjectAltName
: 55 1d 11
0529 04
15 21: . . . . . OCTET STRING
: 30 13 86 11 68 74 74 70
3a 2f 2f 61 63 2e 75 70
: 63 2e 65 73 2f
0552 30
19 25: . . . . SEQUENCE
0554 06
03 3: . . . . . OID 2.5.29.18:
issuerAltName
: 55 1d 12
0559 04
12 18: . . . . . OCTET STRING
: 30 14 86 12 68 74 74 70
3a 2f 2f 77 77 77 2e 75
: 70 63 2e 65
Housley,
et. al. Standards Track [Page 125]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
0579 30
80 : . SEQUENCE (indefinite
length)
0581 06
07 7: . . OID
0583 05
00 0: . . NULL
0585 00
00 0: . . end of contents
marker
0587 03
81 81 47: . BIT STRING
: 00 (0 unused bits)
: 5c 01 bd b5 41 88 87 7a
0e d3 0e 6b 3a bf 04 ea
: 04 cb 5f 61 72 3c a3 bd
78 f5 66 17 fe 37 3a ab
: eb 67 bf b7 da a8 38 f6
33 15 71 75 2f b9 8c 91
: a0 e4 87 ba 4b 43 a0 22
8f d3 a9 86 43 89 e6 50
: 5c 01 bd b5 41 88 87 7a
0e d3 0e 6b 3a bf 04 ea
: 04 cb 5f 61 72 3c a3 bd
78 f5 66 17 fe 37 3a ab
: eb 67 bf b7 da a8 38 f6
33 15 71 75 2f b9 8c 91
: a0 e4 87 ba 4b 43 a0 22
8f d3 a9 86 43 89 e6 50
0637 00
00 0: . . end of contents
marker
D.4
Certificate Revocation List
This section contains an annotated hex dump
of a version 2 CRL with
one extension (cRLNumber). The CRL was
issued by OU=nist;O=gov;C=us
on July 7, 1996; the next scheduled
issuance was August 7, 1996. The
CRL includes one revoked certificates:
serial number 18 (12 hex).
The CRL itself is number 18, and it was
signed with DSA and SHA-1.
0000 30
81 ba 186: SEQUENCE
0003 30
7c 124: . SEQUENCE
0005 02
01 1: . . INTEGER 1
: 01
0008 30
09 9: . . SEQUENCE
0010 06
07 7: . . . OID
1.2.840.10040.4.3: dsa-with-sha
: 2a 86 48 ce 38 04 03
0019 30
2a 42: . . SEQUENCE
0021 31
0b 11: . . . SET
0023 30
09 9: . . . . SEQUENCE
0025 06
03 3: . . . . . OID 2.5.4.6: C
: 55 04 06
0030 13
02 2: . . . . .
PrintableString 'US'
: 55 53
0034 31
0c 12: . . . SET
0036 30
0a 10: . . . . SEQUENCE
0038 06
03 3: . . . . . OID 2.5.4.10: O
: 55 04 0a
0043 13
03 3: . . . . .
PrintableString 'gov'
: 67 6f 76
0048 31
0d 13: . . . SET
0050 30
0b 11: . . . . SEQUENCE
0052 06
03 3: . . . . . OID 2.5.4.11:
OU
: 55 04 0b
Housley,
et. al. Standards Track [Page 126]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
0057 13
04 4: . . . . .
PrintableString 'nist'
: 6e 69 73 74
0063 17
0d 13: . . UTCTime '970801000000Z'
: 39 37 30 38 30 31 30 30
30 30 30 30 5a
0078 17
0d 13: . . UTCTime '970808000000Z'
: 39 37 30 38 30 38 30 30 30 30 30 30 5a
0093 30
22 34: . . SEQUENCE
0095 30
20 32: . . . SEQUENCE
0097 02
01 1: . . . . INTEGER 18
: 12
0100 17
0d 13: . . . . UTCTime '970731000000Z'
: 39 37 30 37 33 31 30 30 30 30 30 30 5a
0115 30
0c 12: . . . . SEQUENCE
0117 30
0a 10: . . . . . SEQUENCE
0119 06
03 3: . . . . . . OID
2.5.29.21: reasonCode
: 55 1d 15
0124 04
03 3: . . . . . . OCTET STRING
: 0a 01 01
0129 30
09 9: . SEQUENCE
0131 06
07 7: . . OID
1.2.840.10040.4.3: dsa-with-sha
: 2a 86 48 ce 38 04 03
0140 03
2f 47: . BIT STRING (0 unused bits)
: 30 2c 02 14 9e d8 6b c1
7d c2 c4 02 f5 17 84 f9
: 9f 46 7a ca cf b7 05 8a
02 14 9e 43 39 85 dc ea
: 14 13 72 93 54 5d 44 44
e5 05 fe 73 9a b2
Housley,
et. al. Standards Track [Page 127]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
Appendix
E. Authors' Addresses
Russell Housley
SPYRUS
381 Elden Street
Suite 1120
Herndon, VA 20170
USA
EMail: housley@spyrus.com
Warwick Ford
VeriSign, Inc.
One Alewife Center
Cambridge, MA 02140
USA
EMail: wford@verisign.com
Tim Polk
NIST
Building 820, Room 426
Gaithersburg, MD 20899
USA
EMail: wpolk@nist.gov
David Solo
Citicorp
666 Fifth Ave, 3rd Floor
New York, NY 10103
USA
EMail: david.solo@citicorp.com
Housley,
et. al. Standards Track [Page 128]
RFC
2459 Internet X.509 Public Key
Infrastructure January 1999
Appendix
F. Full Copyright Statement
Copyright (C) The Internet Society
(1999). All Rights Reserved.
This document and translations of it may be
copied and furnished to
others, and derivative works that comment
on or otherwise explain it
or assist in its implementation may be
prepared, copied, published
and distributed, in whole or in part,
without restriction of any
kind, provided that the above copyright
notice and this paragraph are
included on all such copies and derivative
works. 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 needed
for the purpose of
developing Internet standards in which case
the procedures for
copyrights defined in the Internet
Standards process must be
followed, or 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.
Housley,
et. al. Standards Track [Page 129]