A Profile for X.509 PKIX
Resource CertificatesAsia Pacific Network Information
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Routing Area
SIDRThis document defines a standard profile for X.509
certificates for the purposes of supporting validation of
assertions of "right-to-use" of an Internet Number Resource (IP
Addresses and Autonomous System Numbers). This profile is used
to convey the issuer's authorization of the subject to be
regarded as the current holder of a "right-of-use" of the IP
addresses and AS numbers that are described in the issued
certificate.This document defines a standard profile for X.509
certificates for use in the context of certification of IP
Addresses and AS Numbers. Such certificates are termed here
"Resource Certificates." Resource Certificates are X.509
certificates that conform to the PKIX profile , and also conform to the constraints
specified in this profile. Resource Certificates attest that the
issuer has granted the subject a "right-to-use" for a listed set
of IP addresses and Autonomous System numbers.A Resource Certificate describes an action by a certificate
issuer that binds a list of IP Address blocks and AS Numbers to
the subject of the issued certificate. The binding is identified
by the association of the subject's private key with the
subject's public key contained in the Resource Certificate, as
signed by the private key of the certificate's issuer.In the context of the public Internet, and the use of public
number resources within this context, it is intended that
Resource Certificates are used in a manner that is explicitly
aligned to the public number resource distribution
function. Specifically, when a number resource is allocated or
assigned by a number registry to an entity, this allocation is
described by an associated Resource Certificate. This
certificate is issued by the number registry, and the subject's
public key that is being certified by the issuer corresponds to
the public key part of a public / private key pair that was
generated by the same entity who is the recipient of the number
assignment or allocation. A critical extension to the
certificate enumerates the IP Resources that were allocated or
assigned by the issuer to the entity. In the context of the
public number distribution function, this corresponds to a
hierarchical PKI structure, where Resource Certificates are only
issued in one 'direction' and there is a single unique path of
certificates from a certificate authority operating at the apex
of a resource distribution hierarchy to a valid certificate.Validation of a Resource Certificate in such a hierarchical
PKI can be undertaken by establishing a valid issuer-subject
certificate chain from a certificate issued by a trust anchor
certificate authority to the certificate , with the additional constraint of
ensuring that each subject's listed resources are fully
encompassed by those of the issuer at each step in the
issuer-subject certificate chain.Resource Certificates may be used in the context of the
operation of secure inter-domain routing protocols to convey a
right-to-use of an IP number resource that is being passed
within the routing protocol, allowing relying parties to verify
legitimacy and correctness of routing information. Related use
contexts include validation of Internet Routing Registry
objects, validation of routing requests, and detection of
potential unauthorised use of IP addresses.This profile defines those fields that are used in a Resource
Certificate that MUST be present for the certificate to be
valid. Relying Parties SHOULD check that a Resource Certificate
conforms to this profile as a requisite for validation of a
Resource Certificate.It is assumed that the reader is familiar with the terms
and concepts described in "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile" , "X.509
Extensions for IP Addresses and AS Identifiers" , "Internet Protocol" , "Internet Protocol Version 6 (IPv6)
Addressing Architecture" ,
"Internet Registry IP Allocation Guidelines" , and related regional Internet
registry address management policy documents.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.The framework for describing an association between the
subject of a certificate and the resources currently under the
subject's control is described in .There are three aspects of this resource extension that are
noted in this profile: RFC 3779 notes that a resource extension SHOULD be a
CRITICAL extension to the X.509 Certificate. This Resource
Certificate profile further specifies that the use of this
certificate extension MUST be used in all Resource
Certificates and MUST be marked as CRITICAL. RFC 3779 defines a sorted canonical form of describing a
resource set, with maximal spanning ranges and maximal
spanning prefix masks as appropriate. All valid certificates
in this profile MUST use this sorted canonical form of
resource description in the resource extension
field. A test of the resource extension in the context of
certificate validity includes the condition that the
resources described in the immediate superior certificate in
the PKI hierarchy (the certificate where this certificate's
issuer is the subject) has a resource set (called here the
"issuer's resource set") that must encompass the resource
set of the issued certificate. In this context "encompass"
allows for the issuer's resource set to be the same as, or a
strict superset of, any subject's resource set. A test of certificate validity entails the identification of
a sequence of valid certificates in an issuer-subject chain
(where the subject field of one certificate appears as the
issuer in the next certificate in the sequence) from a trust
anchor certificate authority to the certificate being validated,
and that the resource extensions in this certificate sequence
from the trust anchor's issued certificate to the certificate
being validated form a sequence of encompassing relationships in
terms of the resources described in the resource extension.A Resource Certificate is a valid X.509 v3 public key
certificate, consistent with the PKIX profile , containing the fields listed in this
section. Unless specifically noted as being OPTIONAL, all the
fields listed here MUST be present, and any other field MUST NOT
appear in a conforming Resource Certificate. Where a field value
is specified here this value MUST be used in conforming Resource
Certificates.Resource Certificates are X.509 Version 3 certificates.
This field MUST be present, and the Version MUST be 3
(i.e. the value of this field is 2).The serial number value is a positive integer that is
unique per Issuer.This field describes the algorithm used to compute the
signature on this certificate. This profile specifies a
minimum of SHA-256 with RSA (sha256WithRSAEncryption), and
allows for the use of SHA-384 or SHA-512. Accordingly, the
value for this field MUST be one of the OID values { pkcs-1 11
}, { pkcs-1 12 } or { pkcs-1 13 } .It is noted that larger key sizes are computationally
expensive for both the Certificate Authority and relying
parties, indicating that care should be taken when deciding to
use larger than the minimum key size.This field identifies the entity that has signed and issued
the certificate. The value of this field is a valid X.501
name.If the certificate is a subordinate certificate issued by
virtue of the "cA" bit set in the immediate superior
certificate, then the issuer name MUST correspond to the
subject name as contained in the immediate superior
certificate.This field MUST be non-empty.This field identifies the entity to whom the resource has
been allocated / assigned. The value of this field is a valid
X.501 name.In this profile the subject name is determined by the
issuer, and each distinct entity certified by the issuer MUST
be identified using a subject name that is unique per
issuer.This field MUST be non-empty.The starting time at which point the certificate is
valid. In this profile the "Valid From" time SHOULD be no
earlier than the time of certificate generation. As per
Section 4.1.2.5 of ,
Certification Authorities (CAs) conforming to this profile
MUST always encode the certificate's "Valid From" date through
the year 2049 as UTCTime, and dates in 2050 or later MUST be
encoded as GeneralizedTime. These two time formats are defined
in .In this profile, it is valid for a certificate to have a
value for this field that pre-dates the same field value in
any superior certificate. However, it is not valid to infer
from this information that a certificate was, or will be,
valid at any particular time other than the current time.The Valid To time is the date and time at which point in
time the certificate's validity ends. It represents the
anticipated lifetime of the resource allocation / assignment
arrangement between the issuer and the subject. As per Section
4.1.2.5 of , CAs conforming to
this profile MUST always encode the certificate's "Valid To"
date through the year 2049 as UTCTime, and dates in 2050 or
later MUST be encoded as GeneralizedTime. These two time
formats are defined in .In this profile, it is valid for a certificate to have a
value for this field that post-dates the same field value in
any superior certificate. However, it is not valid to infer
from this information that a certificate was, or will be,
valid at any particular time other than the current time.CAs are typically advised against issuing a certificate
with a validity interval that exceeds the validity interval of
the CA's certificate that will be used to validate the issued
certificate. However, in the context of this profile, it is
anticipated that a CA may have valid grounds to issue a
certificate with a validity interval that exceeds the validity
interval of the CA's certificate.This field specifies the subject's public key and the
algorithm with which the key is used. The public key algorithm
MUST be RSA, and, accordingly, the OID for the public key
algorithm is 1.2.840.113549.1.1.1. The key size MUST be a
minimum size of 1024 bits. In the context of certifying
resources it is recommended that the key size of keys that are
intended to be used at the apex of a certificate issuance
hierarchy, and their immediate subordinates, SHOULD use a
minimum key size of 2048 bits. Immediate subordinates of
these certificates, when used in the context of continued
levels of high trust, SHOULD use a minimum key size of 2048
bits.In the application of this profile to certification of
public number resources, it would be consistent with this
recommendation that the Regional Internet Registries use a key
size of 2048 bits in their issued certificates, and that their
immediate subordinate certificate authorities also use a key
size of 2048 bits. All other subordinate certificates MAY use
a key size of 1024 bits.It is noted that larger key sizes are computationally
expensive for both the CA and relying parties, indicating that
care should be taken when deciding to use larger than the
minimum key size.As noted in Section 4.2 of ,
each extension in a certificate is designated as either
critical or non-critical. A certificate-using system MUST
reject the certificate if it encounters a critical extension
it does not recognise; however, a non-critical extension MAY
be ignored if it is not recognised .The following X.509 V3 extensions MUST be present in a
conforming Resource Certificate, except where explicitly noted
otherwise.The basic constraints extension identifies whether the
subject of the certificate is a CA and the maximum depth of
valid certification paths that include this certificate.The issuer determines whether the "cA" boolean is set. If
this bit is set, then it indicates that the subject is
allowed to issue resources certificates within this overall
framework (i.e. the subject is permitted be a CA).The Path Length Constraint is not specified in this
profile and MUST NOT be present.The Basic Constraints extension field is a critical
extension in the Resource Certificate profile, and MUST be
present when the subject is a CA, and MUST NOT be present
otherwise.The subject key identifier extension provides a means of
identifying certificates that contain a particular public
key. To facilitate certification path construction, this
extension MUST appear in all Resource Certificates. This
extension is non-critical.The value of the subject key identifier MUST be the value
placed in the key identifier field of the Authority Key
Identifier extension of immediate subordinate certificates
(all certificates issued by the subject of this
certificate).The Key Identifier used here is the 160-bit SHA-1 hash of
the value of the DER-encoded ASN.1 bit string of the subject
public key, as described in Section 4.2.1.2 of .The authority key identifier extension provides a means of
identifying certificates that are signed by the issuer's
private key, by providing a hash value of the issuer's
public key. To facilitate path construction, this extension
MUST appear in all Resource Certificates. The keyIdentifier
sub field MUST be present in all Resource Certificates, with
the exception of a CA who issues a "self-signed"
certificate. The authorityCertIssuer and
authorityCertSerialNumber sub fields MUST NOT be
present. This extension is non-critical.The Key Identifier used here is the 160-bit SHA-1 hash of
the value of the DER-encoded ASN.1 bit string of the
issuer's public key, as described in Section 4.2.1.1 of
.This describes the purpose of the certificate. This is a
critical extension, and it MUST be present.In certificates issued to Certificate Authorities only the
keyCertSign and CRLSign bits are set to TRUE and MUST be the
only bits set to TRUE. In end-entity certificates the digitalSignature bit MUST
be set and MUST be the only bit set to TRUE.This field (CRLDP) identifies the location(s) of the
CRL(s) associated with certificates issued by this
Issuer. This profile uses the URI form of object
identification. The preferred URI access mechanism is a
single RSYNC URI ("rsync://")
that references a single inclusive CRL for each issuer.In this profile the certificate issuer is also the CRL
issuer, implying at the CRLIssuer sub field MUST be omitted,
and the distributionPoint sub-field MUST be present. The
Reasons sub-field MUST be omitted.The distributionPoint MUST contain general names, and
MUST NOT contain a nameRelativeToCRLIssuer. The type of the
general name MUST be of type URI.In this profile, the scope of the CRL is specified to be
all certificates issued by this CA issuer using a given key
pair.The sequence of distributionPoint values MUST contain
only a single DistributionPointName set. The
DistributionPointName set MAY contain more than one URI
value. An RSYNC URI MUST be present in the
DistributionPointName set, and reference the most recent
instance of this issuer's certificate revocation list. Other
access form URIs MAY be used in addition to the RSYNC
URI.This extension MUST be present and it is
non-critical. There is one exception; where a CA distributes
its public key in the form of a "self-signed" certificate,
the CRLDP MUST be omitted. This field (AIA) identifies the point of publication of
the certificate that is issued by the issuer's immediate
superior CA, where this certificate's issuer is the
subject. In this profile a single reference object to
publication location of the immediate superior certificate
MUST be used, except in the case where a CA distributes its
public key in the form of a "self-signed" certificate, the
AIA field SHOULD be omitted.This profile uses a URI form of object
identification. The preferred URI access mechanisms is
"rsync", and an RSYNC URI MUST be specified with an
accessMethod value of id-ad-caIssuers. The URI MUST
reference the point of publication of the certificate where
this issuer is the subject (the issuer's immediate superior
certificate). Other access method URIs referencing the same
object MAY also be included in the value sequence of this
extension.When an Issuer re-issues a CA certificate, the
subordinate certificates need to reference this new
certificate via the AIA field. In order to avoid the
situation where a certificate re-issuance necessarily
implies a requirement to re-issue all subordinate
certificates, CA Certificate issuers SHOULD use a persistent
URL name scheme for issued certificates. This implies that
re-issued certificates overwrite previously issued
certificates to the same subject in the publication
repository, and use the same publication name as previously
issued certificates. In this way subordinate certificates
can maintain a constant AIA field value and need not be
re-issued due solely to a re-issue of the superior
certificate. The issuers' policy with respect to the
persistence of name objects of issued certificates MUST be
specified in the Issuer's Certificate Practice
Statement.This extension is non-critical.This field (SIA) identifies the location of information
and services relating to the subject of the certificate in
which the SIA extension appears. Where the Subject is a CA
in this profile, this information and service collection
will include all current valid certificates that have been
issued by this subject that are signed with the subject's
corresponding private key.This profile uses a URI form of location identification. The
preferred URI access mechanism is "rsync", and an RSYNC URI MUST be
specified, with an access method value of id-ad-caRepository when
the subject of the certificate is a CA. The RSYNC URI must reference
an object collection rather than an individual object and MUST use a
trailing '/' in the URI.Other access method URIs that reference the same location
MAY also be included in the value sequence of this
extension. The ordering of URIs in this sequence reflect the
subject's relative preferences for access methods, with the
first method in the sequence being the most preferred.This field MUST be present when the subject is a CA, and
is non-critical.For End Entity (EE) certificates, where the subject is
not a CA, this field MAY be present, and is non-critical.
If present, it either references the location where objects
signed by the key pair associated with the EE certificate
can be accessed, or, in the case of single-use EE
certificates it references the location of the single object
that has been signed by the corresponding key pair.When the subject is an End Entity, and it publishes
objects signed with the matching private key in a
repository, the directory where these signed objects is
published is referenced the id-ad-signedObjectRepository
OID.
id-ad OBJECT IDENTIFIER ::= { id-pkix 48 }
id-ad-signedObjectRepository OBJECT IDENTIFIER ::= { id-ad 9 }
When the subject is an End Entity, and it publishes a
single object signed with the matching private key, the
location where this signed object is published is referenced
the id-ad-signedObject OID.
id-ad-signedObject OBJECT IDENTIFIER ::= { id-ad 11 }
This profile requires the use of repository publication
manifests to list all
signed objects that are deposited in the repository
publication point associated with a CA or an EE. The
publication point of the manifest for a CA or EE is placed in
the SIA extension of the CA or EE certificate. This profile
uses a URI form of manifest identification for the
accessLocation. The preferred URI access mechanisms is
"rsync", and an RSYNC URI MUST be specified. Other
accessDescription fields may exist with this id-ad-Manifest
accessMethod, where the accessLocation value indicates
alternate URI access mechanisms for the same manifest object.
id-ad-rpkiManifest OBJECT IDENTIFIER ::= { id-ad 10 }
CA certificates MUST include in the SIA an accessMethod
OID of id-ad-rpkiManifest, where the associated
accessLocation refers to the subject's published manifest
object as an object URL.When an EE certificate is intended for use in verifying
multiple objects, EE certificate MUST include in the SIA an
access method OID of id-ad-rpkiManifest, where the associated
access location refers to the publication point of the
objects that are verified using this EE certificate.When an EE certificate is used to sign a single object,
the EE certificate MUST include in the SIA an access method
OID of id-ad-signedObject, where the associated access
location refers to the publication point of the single object
that is verified using this EE certificate. In this case, the
SIA MUST NOT include the access method OID of
id-ad-rpkiManifest.This extension MUST reference the Resource Certificate
Policy, using the OID Policy Identifier value of
"1.3.6.1.5.5.7.14.2". This field MUST be present and MUST
contain only this value for Resource Certificates.PolicyQualifiers MUST NOT be used in this profile.This extension MUST be present and it is critical.This field contains the list of IP address resources as
per . The value may specify
the "inherit" element for a particular AFI value. In the
context of resource certificates describing public number
resources for use in the public Internet, the SAFI value
MUST NOT be used. All Resource Certificates MUST include an
IP Resources extension, an AS Resources extension, or both
extensions.This extension, if present, MUST be marked critical.This field contains the list of AS number resources as
per , or may specify the
"inherit" element. RDI values are NOT supported in this
profile and MUST NOT be used. All Resource Certificates MUST
include an IP Resources extension, an AS Resources
extension, or both extensions.This extension, if present, MUST be marked critical.Each CA MUST issue a version 2 Certificate Revocation List
(CRL), consistent with . The CRL
issuer is the CA, and no indirect CRLs are supported in this
profile.An entry MUST NOT be removed from the CRL until it appears on
one regularly scheduled CRL issued beyond the revoked
certificate's validity period.This profile does not allow issuance of Delta CRLs.The scope of the CRL MUST be "all certificates issued
by this CA using a given key pair". The contents of the CRL are
a list of all non-expired certificates issued by the CA using a
given key pair that have been revoked by the CA.The profile allows the issuance of multiple current CRLs with
different scope by a single CA, with the scope being defined by
the key pair used by the CA.No CRL fields other than those listed here are permitted in
CRLs issued under this profile. Unless otherwise indicated,
these fields MUST be present in the CRL. Where two or more CRLs
issued by a single CA with the same scope, the CRL with the
highest value of the "CRL Number" field supersedes all other
CRLs issued by this CA.Resource Certificate Revocation Lists are Version 2
certificates (the integer value of this field is 1).The value of this field is the X.501 name of the issuing CA
who is also the signer of the CRL, and is identical to the
Issuer name in the Resource Certificates that are issued by
this issuer.This field contains the date and time that this CRL was
issued. The value of this field MUST be encoded as UTCTime for
dates through the year 2049, and MUST be encoded as
GeneralizedTime for dates in the year 2050 or later.This is the date and time by which the next CRL SHOULD be
issued. The value of this field MUST be encoded as UTCTime
for dates through the year 2049, and MUST be encoded as
GeneralizedTime for dates in the year 2050 or later.This field contains the algorithm used to sign this
CRL. This profile specifies a minimum of SHA-256 with RSA
(sha256WithRSAEncryption), and allows for the use of SHA-384
or SHA-512. This field MUST be present.It is noted that larger key sizes are computationally
expensive for both the CRL Issuer and relying parties,
indicating that care should be taken when deciding to use
larger than the minimum key size.When there are no revoked certificates, then the revoked
certificate list MUST be absent.For each revoked resource certificate only the following
fields MUST be present. No CRL entry extensions are supported
in this profile, and CRL entry extensions MUST NOT be present
in a CRL.The issuer's serial number of the revoked certificate.The time the certificate was revoked. This time SHOULD
NOT be a future date. The value of this field MUST be
encoded as UTCTime for dates through the year 2049, and MUST
be encoded as GeneralizedTime for dates in the year 2050 or
later.The X.509 v2 CRL format allows extensions to be placed in a
CRL. The following extensions are supported in this profile,
and MUST be present in a CRL.The authority key identifier extension provides a means
of identifying the public key corresponding to the private
key used to sign a CRL. Conforming CRL issuers MUST use the
key identifier method. The syntax for this CRL extension is
defined in section 4.2.1.1 of .This extension is non-critical.The CRL Number extension conveys a monotonically
increasing sequence number of positive integers for a given
CA and scope. This extension allows users to easily
determine when a particular CRL supersedes another CRL. The
highest CRL Number value supersedes all other CRLs issued by
the CA with the same scope.This extension is non-critical.A resource certificate request MAY use either of PKCS#10 or
Certificate Request Message Format (CRMF). A CA Issuer MUST
support PKCS#10 and a CA Issuer may, with mutual consent of the
subject, support CRMF.This profile refines the specification in , as it relates to Resource
Certificates. A Certificate Request Message object, formatted
according to PKCS#10, is passed to a CA as the initial step in
issuing a certificate.This request may be conveyed to the CA via a Registration
Authority (RA), acting under the direction of a Subject.With the exception of the public key related fields, the CA
is permitted to alter any requested field when issuing a
corresponding certificate.This profile applies the following additional constraints
to fields that may appear in a CertificationRequestInfo:
This
field is mandatory and MUST have the value 0.This
field is optional. If present, the value of this field
SHOULD be empty, in which case the issuer MUST generate
a subject name that is unique in the context of
certificates issued by this issuer. If the value of this
field is non-empty, then the CA MAY consider the value
of this field as the subject's suggested subject name,
but the CA is NOT bound to honour this suggestion, as
the subject name MUST be unique per issuer in
certificates issued by this issuer. This field specifies the subject's
public key and the algorithm with which the key is
used. The public key algorithm MUST be RSA, and the OID
for the algorithm is 1.2.840.113549.1.1.1. This field
also includes a bit-string representation of the
entity's public key. For the RSA public-key algorithm
the bit string contains the DER encoding of a value of
PKCS #1 type RSAPublicKey. defines the attributes field as
key-value pairs where the key is an OID and the value's
structure depends on the key.The only attribute used in this profile is the
ExtensionRequest attribute as defined in . This attribute contains X509v3
Certificate Extensions. The profile for extensions in
certificate requests is specified in .This profile applies the following additional constraints
to fields that MAY appear in a CertificationRequest Object:
This profile specifies a minimum of SHA-256 with RSA
(sha256WithRSAEncryption), and allows for the use of
SHA-384 or SHA-512. Accordingly, the value for this
field MUST be one of the OID values { pkcs-1 11 }, {
pkcs-1 12 } or { pkcs-1 13 }
.It is noted that larger key sizes are computationally
expensive for both the CA and relying parties,
indicating that care should be taken when deciding to
use larger than the minimum key size.This profile refines the Certificate Request Message Format
(CRMF) specification in , as it
relates to Resource Certificates. A Certificate Request
Message object, formatted according to the CRMF, is passed to
a CA as the initial step in issuing a certificate.This request MAY be conveyed to the CA via a Registration
Authority (RA), acting under the direction of a subject.With the exception of the public key related fields, the CA
is permitted to alter any requested field when issuing a
corresponding certificate.This profile applies the following additional constraints
to fields that may appear in a Certificate Request Template:
This
field MAY be absent, or MAY specify the request of a
Version 3 Certificate. It SHOULD be omitted. As
per , this field is
assigned by the CA and MUST be omitted in this
profile.
As per , this field is
assigned by the CA and MUST be omitted in this
profile. This
field is assigned by the CA and MUST be omitted in this
profile. This
field MAY be omitted. If omitted, the CA will issue a
Certificate with Validity dates as determined by the
CA. If specified, then the CA MAY override the requested
values with dates as determined by the CA. This
field is optional. If present, the value of this field
SHOULD be empty, in which case the issuer MUST generate
a subject name that is unique in the context of
certificates issued by this issuer. If the value of this
field is non-empty, then the CA MAY consider the value
of this field as the subject's suggested subject name,
but the CA is NOT bound to honour this suggestion, as
the subject name MUST be unique per issuer in
certificates issued by this issuer. This
field MUST be present.This
attribute contains X509v3 Certificate Extensions. The
profile for extensions in certificate requests is
specified in .The following control fields are supported in this
profile: It is noted that the intended model of
authentication of the subject is a long term one, and
the advice as offered in
is that the Authenticator Control field be used. The following extensions MAY appear in a PKCS#10 or CRMF
Certificate Request. Any other extensions MUST NOT appear in a
Certificate Request. This profile places the following
additional constraints on these extensions.: If
this is omitted then the CA will issue an end entity
certificate with the BasicConstraints extension not
present in the issued certificate.The Path Length Constraint is not supported in this
Resource Certificate Profile, and this field MUST be
omitted in this profile.The CA MAY honour the SubjectType CA bit set to on. If
this bit is set, then it indicates that the Subject is
allowed to issue resource certificates within this overall
framework.The CA MAY honour the SubjectType CA bit set to off
(End Entity certificate request), in which case the
corresponding end entity certificate will not contain a
BasicConstraints extension. This field is assigned by the CA and MUST be omitted in
this profile. This field is assigned by the CA and
MUST be omitted in this profile. The CA MAY
honor KeyUsage extensions of keyCertSign and
cRLSign if present, as long as this is consistent with
the BasicConstraints SubjectType sub field, when
specified. This field MUST be present when the
subject is a CA, and the field value SHOULD be honoured by
the CA. If the CA is not able to honor the requested field
value, then the CA MUST reject the Certificate
Request. This field (SIA) identifies the location of information
and services relating to the subject of the certificate in
which the SIA extension appears. Where the subject is a CA
in this profile, this information and service collection
will include all current valid certificates that have been
issued by this subject that are signed with the subject's
corresponding private key.This profile uses a URI form of location
identification. An RSYNC URI MUST be specified, with an
access method value of id-ad-caRepository when the subject
of the certificate is a CA. The RSYNC URI MUST reference
an object collection rather than an individual object and
MUST use a trailing '/' in the URI. Other access method
URIs that reference the same location MAY also be included
in the value sequence of this extension. The ordering of
URIs in this sequence reflect the subject's relative
preferences for access methods, with the first method in
the sequence being the most preferred by the
Subject.A request for a CA certificate MUST include in the SIA
of the request the id-ad-caRepository access method, and
also MUST include in the SIA of the request the
accessMethod OID of id-ad-rpkiManifest, where the
associated accessLocation refers to the subject's
published manifest object as an object URL.When an EE certificate is intended for use in verifying
multiple objects, the certificate request for the EE
certificate MUST include in the SIA of the request an
access method OID of id-ad-signedObjectRepository, and
also MUST include in the SIA of the request an access
method OID of id-ad-rpkiManifest, where the associated
access location refers to the publication point of the
objects that are verified using this EE certificate.When an EE certificate is used to sign a single object,
the certificate request for the EE certificate MUST
include in the SIA of the request an access method OID of
id-ad-signedObject, where the associated access location
refers to the publication point of the single object that
is verified using this EE certificate, and MUST NOT
include an id-ad-rpkiManifest access method OID in the SIA
of the request. This field is assigned by the CA and MUST be omitted in
this profile.This field is assigned by the CA and MUST
be omitted in this profile. This field is assigned by the CA and MUST be omitted in
this profile. With the exceptions of the publicKey field and the
SubjectInformationAccess field, the CA is permitted to alter
any requested field.This section describes the Resource Certificate validation
procedure. This refines the generic procedure described in
section 6 of :To meet this goal, the path validation process verifies,
among other things, that a prospective certification path (a
sequence of n certificates) satisfies the following conditions:
for all x in {1, ..., n-1}, the subject of certificate x
is the issuer of certificate x+1; certificate 1 is issued by a trust anchor; certificate n is the certificate to be validated; and
for all x in {1, ..., n}, the certificate is valid.The trust model that may be used in the resource
certificate framework in the context of validation of
assertions of public number resources in public-use contexts
is one that readily maps to a top-down delegated CA model that
mirrors the delegation of resources from a registry
distribution point to the entities that are the direct
recipients of these resources. Within this trust model these
recipient entities may, in turn, operate a registry and
perform further allocations or assignments. This is a strict
hierarchy, in that any number resource and a corresponding
recipient entity has only one 'parent' issuing registry for
that number resource (i.e. there is always a unique parent
entity for any resource and corresponding entity), and that
the issuing registry is not a direct or indirect subordinate
recipient entity of the recipient entity in question (i.e. no
loops in the model).The more general consideration is that selection of a trust
anchor CA is a task undertaken by relying parties. The
structure of the resource certificate profile admits
potentially the same variety of trust models as the PKIX
profile. There is only one additional caveat on the general
applicability of trust models and PKIX frameworks, namely that
in forming a validation path to a trust anchor CA, the
sequence of certificates MUST preserve the resource extension
validation property, as described in , and the validation of the first
certificate in the validation path not only involves the
verification that the certificate was issued by a trust anchor
CA, but also that the resource set described in the
certificate MUST be encompassed by the trust anchor CA's
resource set, as described in .
The trust anchor information, describing a CA that serves as a
trust anchor, includes the following:
the trusted issuer name,the trusted public key algorithm,the trusted public key,optionally, the trusted public key parameters associated
with the public key, anda resource set, consisting of a set of IPv4 resources, IPv6
resources and AS number resources.The trust anchor information may be provided to the path
processing procedure in the form of a self-signed
certificate.The IP resource extension definition defines a critical extensions for
Internet number resources. These are ASN.1 encoded
representations of the IPv4 and IPv6 address range (either as
a prefix/length, or start-end pair) and the AS number set.Valid Resource Certificates MUST have a valid IP address
and/or AS number resource extension. In order to validate a
Resource Certificate the resource extension must also be
validated. This validation process relies on definitions of
comparison of resource sets: Given two IP address or AS
number contiguous ranges, A and B, A is "more specific"
than B if range B includes all IP addresses or AS numbers
described by range A, and if range B is larger than range
A. Given two IP address or AS number
contiguous ranges, A and B, A is "equal" to B if range A
describes precisely the same collection of IP addresses or
AS numbers as described by range B. The definition of
"inheritance" in is
equivalent to this "equality" comparison.Given two IP address and AS
number sets X and Y, X "encompasses" Y if, for every
contiguous range of IP addresses or AS numbers elements in
set Y, the range element is either more specific than or
equal to a contiguous range element within the set X.Validation of a certificate's resource extension in the
context of an ordered certificate sequence of {1,2, ... , n}
where '1'is issued by a trust anchor and 'n' is the target
certificate, and where the subject of certificate 'x' is the
issuer of certificate 'x' + 1, implies that the resources
described in certificate 'x' "encompass" the resources
described in certificate 'x' + 1, and the resources described
in the trust anchor information "encompass" the resources
described in certificate 1.
Validation of signed resource data using a target resource
certificate consists of assembling an ordered sequence (or
'Certificate Path') of certificates ({1,2,...n} where '1' is a
certificate that has been issued by a trust anchor, and 'n' is
the target certificate) verifying that all of the following
conditions hold: The certificate can be verified using the
Issuer's public key and the signature algorithm The current time lies within the certificate's Validity
From and To values. The certificate contains all fields that MUST be
present and contains field values as specified in this
profile for all field values that MUST be present. No field value that MUST NOT be present in this profile
is present in the certificate. The Issuer has not revoked the certificate by placing
the certificate's serial number on the Issuer's current
Certificate Revocation List, and the Certificate
Revocation List is itself valid. That the resource extension data is "encompassed" by
the resource extension data contained in a valid
certificate where this Issuer is the Subject (the previous
certificate in the ordered sequence) The Certificate Path originates with a certificate
issued by a trust anchor, and there exists a signing chain
across the Certificate Path where the Subject of
Certificate x in the Certificate Path matches the Issuer
in Certificate x+1 in the Certificate Path.A certificate validation algorithm may perform these tests
in any chosen order.Certificates and CRLs used in this process may be found in
a locally maintained cache, maintained by a regular top-down
synchronization pass, seeded with the CAs who operate at the
apex of the resource distribution hierarchy, via reference to
Issued certificates and their SIA fields as forward pointers,
plus the CRLDP. Alternatively, validation may be performed
using a bottom-up process with on-line certificate access
using the AIA and CRLDP pointers to guide the certificate
retrieval process.There exists the possibility of encountering certificate
paths that are arbitrarily long, or attempting to generate
paths with loops as means of creating a potential DOS attack
on a certificate validator. Some further heuristics may be
required to halt the certificate path validation process in
order to avoid some of the issues associated with attempts to
validate such structures. It is suggested that implementations
of Resource Certificate validation MAY halt with a validation
failure if the certificate path length exceeds a
pre-determined configuration parameter.The Security Considerations of
and apply to Resource Certificates
as defined by this profile, and their use.A Resource Certificate PKI cannot in and of itself resolve
any forms of ambiguity relating to uniqueness of assertions of
rights of use in the event that two or more valid certificates
encompass the same resource. If the issuance of resource
certificates is aligned to the status of resource allocations
and assignments then the information conveyed in a certificate
is no better than the information in the allocation and
assignment databases. [Note to IANA, to be removed prior to publication: there are
no IANA considerations stated in this version of the
document.]The authors would like to acknowledge the valued
contributions from Stephen Kent, Robert Kisteleki, Randy Bush,
Russ Housley, Ricardo Patara and Rob Austein in the preparation
and subsequent review of this document. The document also reflects
review comments received from Sean Turner.Manifests for the Resource Public Key InfrastructureISCAPNICBBNBBNrsyncSAMBAThe following is an example Resource Certificate.The following is an example Certificate Revocation List.