draft-ietf-wpkops-trustmodel-00.txt   draft-ietf-wpkops-trustmodel-01.txt 
Internet Engineering Task Force I. Barreira, Ed. Internet Engineering Task Force I. Barreira, Ed.
Internet-Draft Izenpe Internet-Draft Izenpe
Intended status: Best Current Practice B. Morton, Ed. Intended status: Best Current Practice B. Morton, Ed.
Expires: April 24, 2014 Entrust Expires: November 21, 2014 Entrust
October 21, 2013 May 20, 2014
Trust models of the Web PKI Trust models of the Web PKI
draft-ietf-wpkops-trustmodel-00 draft-ietf-wpkops-trustmodel-01
Abstract Abstract
This is one of a set of documents to define the operation of the Web This is one of a set of documents to define the operation of the Web
PKI. It describes the currently deployed Web PKI trust model. PKI. It describes the currently deployed Web PKI trust.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 24, 2014. This Internet-Draft will expire on November 21, 2014.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2014 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
2. Trust model . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Trust model . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Root store provider . . . . . . . . . . . . . . . . . . . 3 2.1. Root store provider . . . . . . . . . . . . . . . . . . . 4
2.2. CA Infrastructure . . . . . . . . . . . . . . . . . . . . 4 2.2. CA Infrastructure . . . . . . . . . . . . . . . . . . . . 4
2.2.1. Registration Authority . . . . . . . . . . . . . . . 4 2.2.1. Registration Authority . . . . . . . . . . . . . . . 5
2.2.2. Certificate status . . . . . . . . . . . . . . . . . 4 2.2.2. Certificate status . . . . . . . . . . . . . . . . . 5
2.3. Subscriber . . . . . . . . . . . . . . . . . . . . . . . 4 2.3. Subscriber . . . . . . . . . . . . . . . . . . . . . . . 5
2.4. Browser . . . . . . . . . . . . . . . . . . . . . . . . . 5 2.4. Browser . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Trust Model variants . . . . . . . . . . . . . . . . . . . . 5 3. Trust Model variants . . . . . . . . . . . . . . . . . . . . 5
3.1. Root store provider variations . . . . . . . . . . . . . 5 3.1. Root store provider variations . . . . . . . . . . . . . 5
3.1.1. Browser adopts root store . . . . . . . . . . . . . . 5 3.1.1. Browser adopts root store . . . . . . . . . . . . . . 5
3.2. CA Infrastructure variations . . . . . . . . . . . . . . 5 3.2. CA Infrastructure variations . . . . . . . . . . . . . . 6
3.2.1. One root CA cross-certifies another root CA . . . . . 5 3.2.1. One root CA cross-certifies another root CA . . . . . 6
3.2.2. Issuing CA is a third party to the root CA . . . . . 5 3.2.2. Issuing CA is a third party to the root CA . . . . . 6
3.2.3. Registration authority is a third party to the 3.2.3. Registration authority is a third party to the
issuing CA . . . . . . . . . . . . . . . . . . . . . 6 issuing CA . . . . . . . . . . . . . . . . . . . . . 6
3.2.4. Root CA is operated by the government . . . . . . . . 6 3.2.4. Root CA is operated by the government . . . . . . . . 7
3.2.5. Subscriber operates issuing CA . . . . . . . . . . . 6 3.2.5. Subscriber operates issuing CA . . . . . . . . . . . 7
3.2.6. Subscriber sources management of issuing CA . . . . . 6 3.2.6. Subscriber sources management of issuing CA . . . . . 7
3.2.7. Subscriber manages registration authority . . . . . . 6 3.2.7. Subscriber manages registration authority . . . . . . 7
3.2.8. Subscriber certificate issued by a root CA . . . . . 7 3.2.8. Subscriber certificate issued by a root CA . . . . . 7
3.3. Subscriber . . . . . . . . . . . . . . . . . . . . . . . 7 3.3. Subscriber . . . . . . . . . . . . . . . . . . . . . . . 8
3.3.1. Subscriber uses agent . . . . . . . . . . . . . . . . 7 3.3.1. Subscriber uses agent . . . . . . . . . . . . . . . . 8
3.4. Browser . . . . . . . . . . . . . . . . . . . . . . . . . 7 3.4. Browser . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.4.1. Browser directly trusts issuing CA key . . . . . . . 7 3.4.1. Browser directly trusts issuing CA key . . . . . . . 8
3.4.2. Browser directly trusts subscriber entity key . . . . 7 3.4.2. Browser directly trusts subscriber entity key . . . . 8
3.4.3. Browser supports public key pinning . . . . . . . . . 7 3.4.3. Browser makes root CA public key unusable . . . . . . 8
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 3.4.4. Browser supports public key pinning . . . . . . . . . 8
5. Security Considerations . . . . . . . . . . . . . . . . . . . 7 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8
5.1. HTTPS is optional . . . . . . . . . . . . . . . . . . . . 8 5. Security Considerations . . . . . . . . . . . . . . . . . . . 8
5.2. Naming of subscribers . . . . . . . . . . . . . . . . . . 8 5.1. HTTPS is optional . . . . . . . . . . . . . . . . . . . . 9
5.3. Root CA compromise . . . . . . . . . . . . . . . . . . . 8 5.2. Naming of subscribers . . . . . . . . . . . . . . . . . . 9
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.3. Root CA compromise . . . . . . . . . . . . . . . . . . . 9
6.1. Normative References . . . . . . . . . . . . . . . . . . 9 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
6.2. Informative References . . . . . . . . . . . . . . . . . 9 6.1. IETF Normative References . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 6.2. IETF Informative References . . . . . . . . . . . . . . . 10
Appendix A. Other references . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
This document defines the Web PKI trust model as it is currently This document defines the Web PKI trust model as it is currently
implemented. The trust model is to support communications between implemented. The trust model is to support communications between
the subscriber and the browser. This document does not address the subscriber and the browser. This document does not address
future changes to the implemented trust model. future changes to the implemented trust model.
1.1. Definitions 1.1. Requirements Language
The use of PKI terminology is used as defined in RFC 5280. The key words "REQUIRED", "MUST", "MUST NOT" and "MAY" in this
document are to be interpreted as described in RFC 2119 [RFC2119]
1.2. Definitions
The use of PKI terminology is used as defined in RFC 5280 [RFC5280].
Additional definitions are provided below for interpretation of this Additional definitions are provided below for interpretation of this
document. document.
Certificate policy - per RFC 3647. Certificate policy - per RFC 3647. [RFC3647]
Root CA - a CA with a self-signed certificate and whose public key Intermediate CA - is a non-root CA which issues certificates to
issuing CAs.
Issuing CA - in relation to a particular subscriber certificate,
the CA that issued the certificate.
Root CA - a CA with a self signed certificate and whose public key
is included as a trust anchor in a root store. is included as a trust anchor in a root store.
Root certificate - typically a self-signed certificate that Root certificate - typically a self-signed certificate that
identifies the root CA. The root certificate is a type of trust identifies the root CA. The root certificate is a type of trust
anchor. anchor.
Root store - a set of root certificates which can be trusted by a Root store - a set of root certificates which can be trusted by a
browser. browser.
Root store policy - the governance policy provided by the root Root store policy - the governance policy provided by the root
store provider. store provider.
Subscriber - per RFC 3647. Subscriber - per RFC 3647. [RFC3647]
Subscriber agreement - per RFC 3647. Subscriber agreement - per RFC 3647. [RFC3647]
Trust anchor - per RFC 5914. Trust Anchor - per RFC 5914. [RFC5914]
2. Trust model 2. Trust model
This section describes the basic Web PKI trust model. Variants to
the trust model are discussed in section 3.
In the Web PKI trust model, a browser uses a root store that contains In the Web PKI trust model, a browser uses a root store that contains
one or more root CA public keys. Each entry in a browser's root one or more root CA public keys. Each entry in a browser's root
store has been installed on an evaluation made by the browser vendor. store has been installed on an evaluation made by the browser vendor.
Each such root CA issues a certificate to one or more issuing CAs Each root CA issues a certificate to one or more issuing CAs that are
that are under the control of the same CA entity. Each issuing CA under the control of the same CA entity with the variant stated in
accepts and responds to certificate requests from one or more 3.2.2. Each issuing CA accepts and responds to certificate requests
subscribers via one or more registration authorities. from one or more subscribers via one or more registration
authorities.
2.1. Root store provider 2.1. Root store provider
A root store provider (e.g., Microsoft or Mozilla) determines a root A root store provider (e.g., Microsoft or Mozilla) determines a root
store policy. This policy must be met by a candidate root CA in store policy. This policy must be met by a candidate root CA in
order to be included in the root store. The root store provider order to be included in the root store. The root store provider
installs and manages root certificates in its operating system or installs and manages root certificates in its operating system or
browser to support certificate chain validation. The root store browser to support certificate chain validation. The root store
provider establishes requirements for accepting a root certificate. provider establishes requirements for accepting a root certificate.
These requirements may include legal agreements, security or audit These requirements may include legal agreements, security or audit
reports by third parties or acceptance by another root store reports or acceptance by another root store provider.
provider.
A root store provider requires the root CA to be subject to an annual The root store provider may require the root CA to be subject to an
compliance audit performed by a third party auditor. The audit annual compliance audit performed by a third party auditor as
requirements are defined by the root store policy. The audit is specified in [BR-certs]. The audit requirements are defined by the
based on an accepted schema of the standards (e.g., WebTrust or root store policy. The audit is based on an accepted schema of the
ETSI). A third party auditor generates an audit report which is standards (e.g., WebTrust or ETSI). A third party auditor generates
provided to the root store provider. If the audit report states the an audit report which is provided to the root store provider. If the
root CA did not comply with the auditing standards, then the root CA audit report states the root CA did not comply with the auditing
will be required to take corrective actions. Once the corrective standards, then the root CA will be required to take corrective
actions are completed, then an updated report is submitted to the actions. Once the corrective actions are completed, then an updated
root store provider. If the status of the root CA is not acceptable report is submitted to the root store provider. If the status of the
to the root store provider, then the root CA certificates may be root CA is not acceptable to the root store provider, then the root
removed from the root store or the indications from the browser may CA certificates may be removed from the root store or the indications
change for certificates verified under that root CA. from the browser (e.g., removal of https indicator) may change for
certificates verified under that root CA.
2.2. CA Infrastructure 2.2. CA Infrastructure
The CA infrastructure consists of a PKI hierarchy. Each organization The CA infrastructure consists of a PKI hierarchy. Each organization
acting as a CA entity is represented by one or more self-signed acting as a CA entity is represented by one or more self-signed root
certificates. The self-signed certificate is called the root certificates. The root CAs sign certificates for subordinate issuing
certificate of a root CA. The root CAs sign certificates for CAs. The root CA may have subordinate intermediate CAs to manage
subordinate issuing CAs. The root CA may have subordinate groups of subordinate issuing CAs. The CA entity manages root,
intermediate CAs to manage groups of subordinate issuing CAs. The CA intermediate, and issuing CAs and oversees operation of the
entity manages root, intermediate, and issuing CAs and oversees certificate issuance and management system in accordance with a
operation of the certificate issuance and management system in certificate policy.
accordance with a certificate policy.
2.2.1. Registration Authority 2.2.1. Registration Authority
Each issuing CA operates a registration authority that authenticates Each issuing CA operates a registration authority, with variations in
requests for certificates in accordance with the certificate policy. 3.2.3 and 3.2.7, which authenticates requests for certificates in
accordance with the certificate policy of the CA.
2.2.2. Certificate status 2.2.2. Certificate status
Each CA provides certificate status in the form of a certificate Each CA provides certificate status in the form of a certificate
revocation list (CRL) and/or an online certificate status protocol revocation list (CRL) and/or an on-line certificate status protocol
(OCSP) response. Updates and validity periods of the certificate (OCSP) response. Updates and validity periods of the certificate
status are provided in accordance with the certificate policy of the status are provided in accordance with the certificate policy of the
CA. The location of the CRL is provided in the certificate CRL CA. The location of the CRL is provided in the certificate CDP (CRL
distribution point (CDP) OID and the location of the OCSP response is Distribution Point) OID and the location of the OCSP response is
provided in the authority info access (AIA) OID of the issued provided in the AIA (Authority Info Access) OID of the issued
certificate. certificate.
2.3. Subscriber 2.3. Subscriber
Each subscriber provides services through the browsers to relying Each subscriber provides services through the browsers to relying
parties. The subscriber identifies the online location of its parties. The subscriber identifies the on-line web location of its
service using a domain name contained in a certificate. The service using a domain name or IP address contained in a certificate.
subscriber submits certificate requests in accordance with a CA's
The subscriber submits certificate requests in accordance with a CA's
certificate policy. Once the certificate request has been accepted, certificate policy. Once the certificate request has been accepted,
the subscriber will receive the certificate and will manage the the subscriber will receive the certificate and will manage the
certificate in accordance with the subscriber agreement. certificate in accordance with the subscriber agreement.
2.4. Browser 2.4. Browser
The browser accepts and manages certificates and performs related The browser accepts and manages certificates and performs related
functions in accordance with the root store policy. functions in accordance with the root store policy (e.g., [Mozilla-
CP]).
3. Trust Model variants 3. Trust Model variants
This section defines variants to the roles of the parties as defined This section defines variants to the roles of the parties as defined
in section 2. in section 2.
3.1. Root store provider variations 3.1. Root store provider variations
3.1.1. Browser adopts root store 3.1.1. Browser adopts root store
The browser does not use its own root store, but uses the root store The browser does not use its own root store, but uses the root store
managed by a separate root store provider. managed by a separate root store provider. For example, the Google
Chrome browser operated on Windows uses the Windows root store.
The browser will provide its own trust and security indications. The
browser may determine whether it will provide extended validation
indications. The browser may also provide its own services to verify
the status of the certificates.
3.2. CA Infrastructure variations 3.2. CA Infrastructure variations
3.2.1. One root CA cross-certifies another root CA 3.2.1. One root CA cross-certifies another root CA
Some browsers in active use do not possess the capability to be Some browsers in active use do not possess the capability to be
updated with new root certificates in the field. Consequently, these updated with new root certificates in the field. Consequently, these
products do not accept certificates issued by CAs that came into browsers do not accept new root certificates issued by CAs that came
existence after they were first deployed; although the certificates into existence after they were first deployed. The new root
of these CAs are accepted by newer products and ones that can be certificates are accepted by newer browsers and other browsers that
updated in the field. As such newer CAs operate at a disadvantage to can be updated in the field. As such newer CAs operate at a
older CAs, and they commonly address this disadvantage by having disadvantage to older CAs.
their public key cross-certified by an older CA.
As the cross-certified root CA is also recognized directly by the The disadvantage can be addressed by having trust extended to the new
root store provider, it operates in accordance with the requirements root certificate, by having the public key of the new root
of that certificate policy, in addition to any requirements placed certificate cross-signed by an older root CA which is already
upon it by the contract between it and the cross-certifying root CA. accepted in the older browsers. As the cross-certified root CA is
also recognized directly by the root store provider, it operates in
accordance with the requirements of that certificate policy to which
the root CA conforms. , inIn addition, the cross-certified CA
complies to any requirements placed upon it by the contract between
it and the cross-certifying root CA.
3.2.2. Issuing CA is a third party to the root CA 3.2.2. Issuing CA is a third party to the root CA
An issuing CA may operate as a third party subordinate to the root An issuing CA may operate as a third party subordinate to the root
CA. The issuing CA's behavior is governed by its contract with the CA. The issuing CA's behaviour is governed by its contract with the
root CA, which commonly stipulates adherence to the root store root CA, which commonly stipulates adherence to the root store
policy. Unlike the situation in section 3.2.1, the subordinate policy. Unlike the situation in section 3.2.1, the subordinate
issuing CA is not recognized independently by any relationship with issuing CA is not recognized independently by any relationship with
the root store provider. the root store provider.
3.2.3. Registration authority is a third party to the issuing CA 3.2.3. Registration authority is a third party to the issuing CA
A registration authority may operate as a third party to an issuing A registration authority may operate as a third party to an issuing
CA. A registration authority's behavior is governed by its contract CA. A registration authority's behaviour is governed by its contract
with the issuing CA, which commonly stipulates adherence to the root with the issuing CA, which commonly stipulates adherence to the root
store policy to which the CA adheres. A third party registration store policy to which the CA adheres. A third party registration
authority is not identified in a CA certificate. authority is not identified in a CA certificate.
3.2.4. Root CA is operated by the government 3.2.4. Root CA is operated by the government
In the case where a root CA is operated by a government department, a In the case where a root CA is operated by a government department, a
root store provider may rely upon an audit conducted in accordance root store provider may rely upon an audit conducted in accordance
with the government's own internal audit process. with the government's own internal audit process.
3.2.5. Subscriber operates issuing CA 3.2.5. Subscriber operates issuing CA
A subscriber may operate its own issuing CA. Typically, the A subscriber may operate its own issuing CA. Typically, the
subscriber is approved to issue certificates only within a specific subscriber is approved to issue certificates only within a specific
region of the name-space, and this limitation is enforced by region of the name-space, and this limitation is enforced by
contract. The root CA may use the name constraints certificate contract. The root CA may use the name constraints certificate
extension to limit the region of the name-space in which the issuing extension to limit the region of the name-space in which the issuing
CA can issue valid certificates. This is often referred to as an CA can issue valid certificates.
enterprise-based subordinate CA relationship.
This is often referred to as an enterprise-based subordinate CA
relationship.
3.2.6. Subscriber sources management of issuing CA 3.2.6. Subscriber sources management of issuing CA
A root CA may host an issuing CA on behalf of a subscriber. A root CA may host an issuing CA on behalf of a subscriber.
Typically, the subscriber is approved to issue certificates only Typically, the subscriber is approved to issue certificates only
within a specific region of the name-space, and this limitation is within a specific region of the name-space, and this limitation is
enforced by the host root CA. Examination of the certificate chain enforced by the host root CA. Examination of the certificate chain
would indicate that the issuing CA was owned and operated by the would indicate that the issuing CA was owned by the subscriber by
subscriber. viewing the organization name in the subject field.
This may also be an enterprise-based CA relationship; however, the This may also be an enterprise-based CA relationship; however, the
entity operating the CA (rather than the enterprise subscriber) has entity operating the CA (rather than the enterprise subscriber) has
immediate control of the CA and physical possession of the CA private immediate control of the CA and physical possession of the CA private
key. key.
3.2.7. Subscriber manages registration authority 3.2.7. Subscriber manages registration authority
A subscriber may manage a registration authority. The subscriber is A subscriber may manage a registration authority. The subscriber is
approved to issue certificates only within a specific region of the approved to issue certificates only within a specific region of the
skipping to change at page 7, line 31 skipping to change at page 8, line 26
3.4.1. Browser directly trusts issuing CA key 3.4.1. Browser directly trusts issuing CA key
A browser may allow a relying party to designate a CA key as a trust A browser may allow a relying party to designate a CA key as a trust
anchor for the purpose of evaluating subscriber certificates. anchor for the purpose of evaluating subscriber certificates.
3.4.2. Browser directly trusts subscriber entity key 3.4.2. Browser directly trusts subscriber entity key
A browser may allow a relying party to designate a subscriber's A browser may allow a relying party to designate a subscriber's
certificate as a trust anchor. certificate as a trust anchor.
3.4.3. Browser supports public key pinning 3.4.3. Browser makes root CA public key unusable
A browser may allow a relying party to remove the trust of a root CA
by deleting the root certificate from the root store. In some cases
the trust removal may only be temporary as the browser or operating
system may update the root store and restore the trust of the root
CA.
3.4.4. Browser supports public key pinning
A browser may limit the set of public keys used to verify a A browser may limit the set of public keys used to verify a
certificate containing a domain name. Limitation can be done by certificate containing a domain name. Limitation can be done by
including the set of accepted public keys in the browser or by including the set of accepted public keys in the browser or by
respecting an HTTP header provided by the subscriber. respecting an HTTP header provided by the subscriber.
4. IANA Considerations 4. IANA Considerations
This memo includes no request to IANA. This memo includes no request to IANA.
skipping to change at page 8, line 11 skipping to change at page 9, line 11
The trust models described here exhibit several vulnerabilities that The trust models described here exhibit several vulnerabilities that
could adversely affect the reliability of the authentication they could adversely affect the reliability of the authentication they
provide. provide.
5.1. HTTPS is optional 5.1. HTTPS is optional
The subscriber does not have to support HTTPS for the web site. The The subscriber does not have to support HTTPS for the web site. The
subscriber may provide HTTPS in some cases and not in other cases. subscriber may provide HTTPS in some cases and not in other cases.
As such, the trust model is optional for each web site. In the event As such, the trust model is optional for each web site. In the event
of no HTTPS, the browser could more easily be attacked. This attack of no HTTPS, the browser could more easily be attacked. This attack
can be mitigated by supporting HSTS in accordance with RFC 6797. can be mitigated by supporting HSTS in accordance with RFC 6797
HSTS allows the subscriber to declare to the browser that [RFC6797]. HSTS allows the subscriber to declare to the browser that
interactions shall only be done using HTTPS connections. interactions shall only be done using HTTPS connections.
5.2. Naming of subscribers 5.2. Naming of subscribers
Subscriber names with any of the following characteristics can be Subscriber names with any of the following characteristics can be
used in an impersonation attack. used in an impersonation attack.
o homographic name o homographic name
o mixed-alphabet name o mixed-alphabet name
o name that contains a string termination character o name that contains a string termination character
o Internet non-unique name (e.g. an internal server name) o Internet non-unique name (e.g. an internal server name)
With the exception of non-unique names, CAs in the Web PKI are With the exception of non-unique names, CAs in the Web PKI are
required to screen out requests for certificates with any of these required to screen out requests for certificates with any of these
characteristics. CAs are required to phase out the practice of characteristics. CAs are required to phase out the practice of
issuing non-unique names by 2015. issuing non-unique names by 2015 per [BR-certs].
Technically, unless constrained by an upstream CA to issue Technically, unless constrained by an upstream CA to issue
certificates only in a specific region of the name-space, any CA in certificates only in a specific region of the name-space, any CA in
the Web PKI can issue an apparently legitimate certificate for any the Web PKI can issue an apparently legitimate certificate for any
name, whether or not the legitimate holder of that name is aware of name, whether or not the legitimate holder of that name is aware of
or approves the issuance. Furthermore, the legitimate holder of that or approves the issuance. Furthermore, the legitimate holder of that
name may not discover that such a certificate has been issued. name may not discover that such a certificate has been issued.
5.3. Root CA compromise 5.3. Root CA compromise
In the event of a detected compromise of a root CA, its key is In the event of a detected compromise of a root CA, its key is
blacklisted by the root store provider by means of a software update. blacklisted by means of a software update. This has the effect of
This has the effect of invalidating every certificate that is invalidating every certificate that is subordinate to that root CA,
subordinate to that root CA, whether or not the certificate was whether or not the certificate was issued while the compromise
issued while the compromise existed. This step would have a severe existed. This step would have a severe impact upon the CA and its
impact upon the CA and its subscribers; this is a step not likely to subscribers; this is a step not likely to be taken without very
be taken without very careful. careful.
6. References 6. References
6.1. Normative References
6.1. IETF Normative References
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, May 2008. (CRL) Profile", RFC 5280, May 2008.
[RFC5914] Housley, R., Ashmore, S., and C. Wallace, "Trust Anchor [RFC5914] Housley, R., Ashmore, S., and C. Wallace, "Trust Anchor
Format", RFC 5914, June 2010. Format", RFC 5914, June 2010.
[RFC6797] Hodges, J., Jackson, C., and A. Barth, "HTTP Strict [RFC6797] Hodges, J., Jackson, C., and A. Barth, "HTTP Strict
Transport Security (HSTS)", RFC 6797, November 2012. Transport Security (HSTS)", RFC 6797, November 2012.
6.2. Informative References 6.2. IETF Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC3647] Chokhani, S., Ford, W., Sabett, R., Merrill, C., and S. [RFC3647] Chokhani, S., Ford, W., Sabett, R., Merrill, C., and S.
Wu, "Internet X.509 Public Key Infrastructure Certificate Wu, "Internet X.509 Public Key Infrastructure Certificate
Policy and Certification Practices Framework", RFC 3647, Policy and Certification Practices Framework", RFC 3647,
November 2003. November 2003.
Appendix A. Other references
[BR-certs] - CA/Browser Forum, Baseline Requirements for the
Issuance and Management of Publicly-Trusted Certificates. https://
cabforum.org/baseline-requirements-documents/
[Mozilla-CP] - Mozilla CA Certificate Policy. https://
www.mozilla.org/projects/security/certs/policy/
Authors' Addresses Authors' Addresses
Inigo Barreira (editor) Inigo Barreira (editor)
Izenpe Izenpe
Beato Tomas de Zumarraga 71, 1. 01008 Vitoria-Gasteiz. Spain Beato Tomas de Zumarraga 71, 1. 01008 Vitoria-Gasteiz. Spain
Phone: +34 945067705 Phone: +34 945067705
Email: i-barreira@izenpe.net Email: i-barreira@izenpe.net
Bruce Morton (editor) Bruce Morton (editor)
Entrust Entrust
1000 Innovation Drive. Ottawa, Ontario. Canada K2K 3E7 1000 Innovation Drive. Ottawa, Ontario. Canada K2K 3E7
Phone: +1 613 2703743
Email: bruce.morton@entrust.com Email: bruce.morton@entrust.com
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