draft-ietf-hip-rfc6253-bis-04.txt   draft-ietf-hip-rfc6253-bis-05.txt 
Host Identity Protocol Heer Host Identity Protocol Heer
Internet-Draft Hirschmann Automation and Control Internet-Draft Albstadt-Sigmaringen University
Intended status: Standards Track Varjonen Obsoletes: 6253 (if approved) Varjonen
Expires: March 25, 2016 University of Helsinki Updates: 7401 (if approved) University of Helsinki
September 22, 2015 Intended status: Standards Track November 3, 2015
Expires: May 6, 2016
Host Identity Protocol Certificates Host Identity Protocol Certificates
draft-ietf-hip-rfc6253-bis-04 draft-ietf-hip-rfc6253-bis-05
Abstract Abstract
The Certificate (CERT) parameter is a container for digital The Certificate (CERT) parameter is a container for digital
certificates. It is used for carrying these certificates in Host certificates. It is used for carrying these certificates in Host
Identity Protocol (HIP) control packets. This document specifies the Identity Protocol (HIP) control packets. This document specifies the
certificate parameter and the error signaling in case of a failed certificate parameter and the error signaling in case of a failed
verification. Additionally, this document specifies the verification. Additionally, this document specifies the
representations of Host Identity Tags in X.509 version 3 (v3) and representations of Host Identity Tags in X.509 version 3 (v3).
Simple Public Key Infrastructure (SPKI) certificates.
The concrete use cases of certificates, including how certificates The concrete use cases of certificates, including how certificates
are obtained, requested, and which actions are taken upon successful are obtained, requested, and which actions are taken upon successful
or failed verification, are specific to the scenario in which the or failed verification, are specific to the scenario in which the
certificates are used. Hence, the definition of these scenario- certificates are used. Hence, the definition of these scenario-
specific aspects is left to the documents that use the CERT specific aspects is left to the documents that use the CERT
parameter. parameter.
This document extends RFC7401 and obsoletes RFC6253. This document extends RFC7401 and obsoletes RFC6253.
skipping to change at page 1, line 46 skipping to change at page 1, line 46
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 March 25, 2016. This Internet-Draft will expire on May 6, 2016.
Copyright Notice Copyright Notice
Copyright (c) 2015 IETF Trust and the persons identified as the Copyright (c) 2015 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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than English.
1. Introduction 1. Introduction
Digital certificates bind pieces of information to a public key by Digital certificates bind pieces of information to a public key by
means of a digital signature, and thus, enable the holder of a means of a digital signature, and thus, enable the holder of a
private key to generate cryptographically verifiable statements. The private key to generate cryptographically verifiable statements. The
Host Identity Protocol (HIP) [RFC7401] defines a new cryptographic Host Identity Protocol (HIP) [RFC7401] defines a new cryptographic
namespace based on asymmetric cryptography. The identity of each namespace based on asymmetric cryptography. The identity of each
host is derived from a public key, allowing hosts to digitally sign host is derived from a public key, allowing hosts to digitally sign
data and issue certificates with their private key. This document data and issue certificates with their private key. This document
specifies the CERT parameter, which is used to transmit digital specifies the CERT parameter, which is used to transmit digital
skipping to change at page 4, line 32 skipping to change at page 4, line 20
The certificates MUST use the algorithms defined in [RFC7401] as the The certificates MUST use the algorithms defined in [RFC7401] as the
signature and hash algorithms. signature and hash algorithms.
The following certificate types are defined: The following certificate types are defined:
+--------------------------------+-------------+ +--------------------------------+-------------+
| Cert format | Type number | | Cert format | Type number |
+--------------------------------+-------------+ +--------------------------------+-------------+
| Reserved | 0 | | Reserved | 0 |
| X.509 v3 | 1 | | X.509 v3 | 1 |
| SPKI | 2 | | Hash and URL of X.509 v3 | 2 |
| Hash and URL of X.509 v3 | 3 | | LDAP URL of X.509 v3 | 3 |
| Hash and URL of SPKI | 4 | | Distinguished Name of X.509 v3 | 4 |
| LDAP URL of X.509 v3 | 5 |
| LDAP URL of SPKI | 6 |
| Distinguished Name of X.509 v3 | 7 |
| Distinguished Name of SPKI | 8 |
+--------------------------------+-------------+ +--------------------------------+-------------+
The next sections outline the use of Host Identity Tags (HITs) in The next sections outline the use of Host Identity Tags (HITs) in
X.509 v3 and in Simple Public Key Infrastructure (SPKI) certificates. X.509 v3. X.509 v3 certificates and the handling procedures are
X.509 v3 certificates and the handling procedures are defined in defined in [RFC5280]. The wire format for X.509 v3 is the
[RFC5280]. The wire format for X.509 v3 is the Distinguished Distinguished Encoding Rules format as defined in [X.690].
Encoding Rules format as defined in [X.690]. The SPKI, the handling
procedures, and the formats are defined in [RFC2693].
Hash and Uniform Resource Locator (URL) encodings (3 and 4) are used Hash and Uniform Resource Locator (URL) encodings (3 and 4) are used
as defined in Section 3.6 of [RFC5996]. Using hash and URL encodings as defined in Section 3.6 of [RFC7296]. Using hash and URL encodings
results in smaller HIP control packets than by including the results in smaller HIP control packets than by including the
certificate(s), but requires the receiver to resolve the URL or check certificate(s), but requires the receiver to resolve the URL or check
a local cache against the hash. a local cache against the hash.
Lightweight Directory Access Protocol (LDAP) URL encodings (5 and 6) Lightweight Directory Access Protocol (LDAP) URL encodings (5 and 6)
are used as defined in [RFC4516]. Using LDAP URL encoding results in are used as defined in [RFC4516]. Using LDAP URL encoding results in
smaller HIP control packets but requires the receiver to retrieve the smaller HIP control packets but requires the receiver to retrieve the
certificate or check a local cache against the URL. certificate or check a local cache against the URL.
Distinguished Name (DN) encodings (7 and 8) are represented by the Distinguished Name (DN) encodings (7 and 8) are represented by the
skipping to change at page 5, line 46 skipping to change at page 5, line 29
IP Address:hit-of-issuer IP Address:hit-of-issuer
X509v3 Subject Alternative Name: X509v3 Subject Alternative Name:
IP Address:hit-of-subject IP Address:hit-of-subject
Example X509v3 extensions: Example X509v3 extensions:
X509v3 Issuer Alternative Name: X509v3 Issuer Alternative Name:
IP Address:2001:24:6cf:fae7:bb79:bf78:7d64:c056 IP Address:2001:24:6cf:fae7:bb79:bf78:7d64:c056
X509v3 Subject Alternative Name: X509v3 Subject Alternative Name:
IP Address:2001:2c:5a14:26de:a07c:385b:de35:60e3 IP Address:2001:2c:5a14:26de:a07c:385b:de35:60e3
Appendix B shows a full example X.509 v3 certificate with HIP Appendix A shows a full example X.509 v3 certificate with HIP
content. content.
As another example, consider a managed Public Key Infrastructure As another example, consider a managed Public Key Infrastructure
(PKI) environment in which the peers have certificates that are (PKI) environment in which the peers have certificates that are
anchored in (potentially different) managed trust chains. In this anchored in (potentially different) managed trust chains. In this
scenario, the certificates issued to HIP hosts are signed by scenario, the certificates issued to HIP hosts are signed by
intermediate Certification Authorities (CAs) up to a root CA. In intermediate Certification Authorities (CAs) up to a root CA. In
this example, the managed PKI environment is neither HIP aware, nor this example, the managed PKI environment is neither HIP aware, nor
can it be configured to compute HITs and include them in the can it be configured to compute HITs and include them in the
certificates. certificates.
When HIP communications are established, the HIP hosts not only need When HIP communications are established, the HIP hosts not only need
to send their identity certificates (or pointers to their to send their identity certificates (or pointers to their
certificates), but also the chain of intermediate CAs (or pointers to certificates), but also the chain of intermediate CAs (or pointers to
the CAs) up to the root CA, or to a CA that is trusted by the remote the CAs) up to the root CA, or to a CA that is trusted by the remote
peer. This chain of certificates SHOULD be sent in a Cert group as peer. This chain of certificates SHOULD be sent in a Cert group as
specified in Section 2. The HIP peers validate each other's specified in Section 2. The HIP peers validate each other's
certificates and compute peer HITs based on the certificate public certificates and compute peer HITs based on the certificate public
keys. keys.
4. SPKI Cert Object and Host Identities 4. Revocation of Certificates
When using SPKI certificates to transmit information related to HIP
hosts, HITs need to be enclosed within the certificates. HITs can
represent an issuer, a subject, or both. In the following, we define
the representation of those identifiers for SPKI given as
S-expressions. Note that the S-expressions are only the human-
readable representation of SPKI certificates. Full HIs are presented
in the public key sequences of SPKI certificates.
As an example, the Host Identity Tag of a host is expressed as
follows:
Format: (hash hit hit-of-host)
Example: (hash hit 2001:23:724d:f3c0:6ff0:33c2:15d8:5f50)
Appendix A shows a full example of a SPKI certificate with HIP
content.
5. Revocation of Certificates
Revocation of X.509 v3 certificates is handled as defined in Revocation of X.509 v3 certificates is handled as defined in
Section 5 of [RFC5280]. Revocation of SPKI certificates is handled Section 5 of [RFC5280].
as defined in Section 5 of [RFC2693].
6. Error Signaling 5. Error Signaling
If the Initiator does not send the certificate that the Responder If the Initiator does not send the certificate that the Responder
requires, the Responder may take actions (e.g. reject the requires, the Responder may take actions (e.g. reject the
connection). The Responder MAY signal this to the Initiator by connection). The Responder MAY signal this to the Initiator by
sending a HIP NOTIFY message with NOTIFICATION parameter error type sending a HIP NOTIFY message with NOTIFICATION parameter error type
CREDENTIALS_REQUIRED. CREDENTIALS_REQUIRED.
If the verification of a certificate fails, a verifier MAY signal If the verification of a certificate fails, a verifier MAY signal
this to the provider of the certificate by sending a HIP NOTIFY this to the provider of the certificate by sending a HIP NOTIFY
message with NOTIFICATION parameter error type INVALID_CERTIFICATE. message with NOTIFICATION parameter error type INVALID_CERTIFICATE.
skipping to change at page 7, line 24 skipping to change at page 6, line 34
The Responder is unwilling to set up an association, The Responder is unwilling to set up an association,
as the Initiator did not send the needed credentials. as the Initiator did not send the needed credentials.
INVALID_CERTIFICATE 50 INVALID_CERTIFICATE 50
Sent in response to a failed verification of a certificate. Sent in response to a failed verification of a certificate.
Notification Data MAY contain n groups of 2 octets (n calculated Notification Data MAY contain n groups of 2 octets (n calculated
from the NOTIFICATION parameter length), in order Cert group and from the NOTIFICATION parameter length), in order Cert group and
Cert ID of the CERT parameter that caused the failure. Cert ID of the CERT parameter that caused the failure.
7. IANA Considerations 6. IANA Considerations
As this document replaces [RFC6253], references to [RFC6253] in IANA As this document replaces [RFC6253], references to [RFC6253] in IANA
registries have to be replaced by references to this document. registries have to be replaced by references to this document. This
document changes Certificate type registry in Section 2.
8. Security Considerations 7. Security Considerations
Certificate grouping allows the certificates to be sent in multiple Certificate grouping allows the certificates to be sent in multiple
consecutive packets. This might allow similar attacks, as IP-layer consecutive packets. This might allow similar attacks, as IP-layer
fragmentation allows, for example, the sending of fragments in the fragmentation allows, for example, the sending of fragments in the
wrong order and skipping some fragments to delay or stall packet wrong order and skipping some fragments to delay or stall packet
processing by the victim in order to use resources (e.g., CPU or processing by the victim in order to use resources (e.g., CPU or
memory). Hence, hosts SHOULD implement mechanisms to discard memory). Hence, hosts SHOULD implement mechanisms to discard
certificate groups with outstanding certificates if state space is certificate groups with outstanding certificates if state space is
scarce. scarce.
Checking of the URL and LDAP entries might allow denial-of-service Checking of the URL and LDAP entries might allow denial-of-service
(DoS) attacks, where the target host may be subjected to bogus work. (DoS) attacks, where the target host may be subjected to bogus work.
Security considerations for SPKI certificates are discussed in Security considerations for X.509 v3 in [RFC5280].
[RFC2693] and for X.509 v3 in [RFC5280].
9. Acknowledgements 8. Acknowledgements
The authors would like to thank A. Keranen, D. Mattes, M. Komu and T. The authors would like to thank A. Keranen, D. Mattes, M. Komu and T.
Henderson for the fruitful conversations on the subject. D. Mattes Henderson for the fruitful conversations on the subject. D. Mattes
most notably contributed the non-HIP aware use case in Section 3. most notably contributed the non-HIP aware use case in Section 3.
10. Normative References 9. References
9.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2693] Ellison, C., Frantz, B., Lampson, B., Rivest, R., Thomas,
B., and T. Ylonen, "SPKI Certificate Theory", RFC 2693,
September 1999.
[RFC4514] Zeilenga, K., "Lightweight Directory Access Protocol [RFC4514] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP): String Representation of Distinguished Names", RFC (LDAP): String Representation of Distinguished Names", RFC
4514, June 2006. 4514, June 2006.
[RFC4516] Smith, M. and T. Howes, "Lightweight Directory Access [RFC4516] Smith, M. and T. Howes, "Lightweight Directory Access
Protocol (LDAP): Uniform Resource Locator", RFC 4516, June Protocol (LDAP): Uniform Resource Locator", RFC 4516, June
2006. 2006.
[RFC4843] Nikander, P., Laganier, J., and F. Dupont, "An IPv6 Prefix
for Overlay Routable Cryptographic Hash Identifiers
(ORCHID)", RFC 4843, April 2007.
[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.
[RFC5996] Kaufman, C., Hoffman, P., Nir, Y., and P. Eronen, [RFC7296] Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T.
"Internet Key Exchange Protocol Version 2 (IKEv2)", RFC Kivinen, "Internet Key Exchange Protocol Version 2
5996, September 2010. (IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October
2014, <http://www.rfc-editor.org/info/rfc7296>.
[RFC6253] Heer, T. and S. Varjonen, "Host Identity Protocol
Certificates", RFC 6253, DOI 10.17487/RFC6253, May 2011,
<http://www.rfc-editor.org/info/rfc6253>.
[RFC7343] Laganier, J. and F. Dupont, "An IPv6 Prefix for Overlay [RFC7343] Laganier, J. and F. Dupont, "An IPv6 Prefix for Overlay
Routable Cryptographic Hash Identifiers Version 2 Routable Cryptographic Hash Identifiers Version 2
(ORCHIDv2)", RFC 7343, DOI 10.17487/RFC7343, September (ORCHIDv2)", RFC 7343, DOI 10.17487/RFC7343, September
2014, <http://www.rfc-editor.org/info/rfc7343>. 2014, <http://www.rfc-editor.org/info/rfc7343>.
[RFC7401] Moskowitz, R., Heer, T., Jokela, P., and T. Henderson, [RFC7401] Moskowitz, R., Heer, T., Jokela, P., and T. Henderson,
"Host Identity Protocol Version 2 (HIPv2)", RFC 7401, "Host Identity Protocol Version 2 (HIPv2)", RFC 7401,
April 2015. April 2015.
[X.690] ITU-T, , "Recommendation X.690 (2002) | ISO/IEC [X.690] ITU-T, , "Recommendation X.690 (2002) | ISO/IEC
8825-1:2002, Information Technology - ASN.1 encoding 8825-1:2002, Information Technology - ASN.1 encoding
rules: Specification of Basic Encoding Rules (BER), rules: Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished Encoding Canonical Encoding Rules (CER) and Distinguished Encoding
Rules (DER)", July 2002. Rules (DER)", July 2002.
Appendix A. SPKI certificate example 9.2. Informative References
This section shows an SPKI certificate with encoded HITs. The
example has been indented for readability.
(sequence [RFC6253] Heer, T. and S. Varjonen, "Host Identity Protocol
(public_key Certificates", RFC 6253, DOI 10.17487/RFC6253, May 2011,
(rsa-pkcs1-sha1 <http://www.rfc-editor.org/info/rfc6253>.
(e #010001#)
(n |yDwznOwX0w+zvQbpWoTnfWrUPLKW2NFrpXbsIcH/QBSLb
k1RKTZhLasFwvtSHAjqh220W8gRiQAGIqKplyrDEqSrJp
OdIsHIQ8BQhJAyILWA1Sa6f5wAnWozDfgdXoKLNdT8ZNB
mzluPiw4ozc78p6MHElH75Hm3yHaWxT+s83M=|
)
)
)
(cert
(issuer
(hash hit 2001:25:2453:698a:9aa:253a:dcb5:981e)
)
(subject
(hash hit 2001:22:ccd6:4715:72a3:2ab1:77e4:4acc)
)
(not-before "2011-01-12_13:43:09")
(not-after "2011-01-22_13:43:09")
)
(signature
(hash sha1 |h5fC8HUMATTtK0cjYqIgeN3HCIMA|)
|u8NTRutINI/AeeZgN6bngjvjYPtVahvY7MhGfenTpT7MCgBy
NoZglqH5Cy2vH6LrQFYWx0MjWoYwHKimEuBKCNd4TK6hrCyAI
CIDJAZ70TyKXgONwDNWPOmcc3lFmsih8ezkoBseFWHqRGISIm
MLdeaMciP4lVfxPY2AQKdMrBc=|
)
)
Appendix B. X.509 v3 certificate example Appendix A. X.509 v3 certificate example
This section shows a X.509 v3 certificate with encoded HITs. This section shows a X.509 v3 certificate with encoded HITs.
Certificate: Certificate:
Data: Data:
Version: 3 (0x2) Version: 3 (0x2)
Serial Number: 0 (0x0) Serial Number: 0 (0x0)
Signature Algorithm: sha1WithRSAEncryption Signature Algorithm: sha1WithRSAEncryption
Issuer: CN=Example issuing host, DC=example, DC=com Issuer: CN=Example issuing host, DC=example, DC=com
Validity Validity
skipping to change at page 10, line 31 skipping to change at page 9, line 4
X509v3 Issuer Alternative Name: X509v3 Issuer Alternative Name:
IP Address:2001:23:8d83:41c5:dc9f:38ed:e742:7281 IP Address:2001:23:8d83:41c5:dc9f:38ed:e742:7281
X509v3 Subject Alternative Name: X509v3 Subject Alternative Name:
IP Address:2001:2c:6e02:d3e0:9b90:8417:673e:99db IP Address:2001:2c:6e02:d3e0:9b90:8417:673e:99db
Signature Algorithm: sha1WithRSAEncryption Signature Algorithm: sha1WithRSAEncryption
83:68:b4:38:63:a6:ae:57:68:e2:4d:73:5d:8f:11:e4:ba:30: 83:68:b4:38:63:a6:ae:57:68:e2:4d:73:5d:8f:11:e4:ba:30:
a0:19:ca:86:22:e9:6b:e9:36:96:af:95:bd:e8:02:b9:72:2f: a0:19:ca:86:22:e9:6b:e9:36:96:af:95:bd:e8:02:b9:72:2f:
30:a2:62:ac:b2:fa:3d:25:c5:24:fd:8d:32:aa:01:4f:a5:8a: 30:a2:62:ac:b2:fa:3d:25:c5:24:fd:8d:32:aa:01:4f:a5:8a:
f5:06:52:56:0a:86:55:39:2b:ee:7a:7b:46:14:d7:5d:15:82: f5:06:52:56:0a:86:55:39:2b:ee:7a:7b:46:14:d7:5d:15:82:
4d:74:06:ca:b7:8c:54:c1:6b:33:7f:77:82:d8:95:e1:05:ca: 4d:74:06:ca:b7:8c:54:c1:6b:33:7f:77:82:d8:95:e1:05:ca:
e2:0d:22:1d:86:fc:1c:c4:a4:cf:c6:bc:ab:ec:b8:2a:1e:4b: e2:0d:22:1d:86:fc:1c:c4:a4:cf:c6:bc:ab:ec:b8:2a:1e:4b:
04:7e:49:9c:8f:9d:98:58:9c:63:c5:97:b5:41:94:f7:ef:93: 04:7e:49:9c:8f:9d:98:58:9c:63:c5:97:b5:41:94:f7:ef:93:
57:29 57:29
Appendix C. Change log Appendix B. Change log
Contents of draft-ietf-hip-rfc6253-bis-00: Contents of draft-ietf-hip-rfc6253-bis-00:
o RFC6253 was submitted as draft-RFC. o RFC6253 was submitted as draft-RFC.
Changes from version 01 to 02: Changes from version 01 to 02:
o Updated the references. o Updated the references.
Changes from version 02 to 03: Changes from version 02 to 03:
o Fixed the nits raised by the working group. o Fixed the nits raised by the working group.
Changes from version 03 to 04: Changes from version 03 to 04:
o Added "obsoletes RFC 6253". o Added "obsoletes RFC 6253".
Changes from version 04 to 05:
o Updates to contact details.
o Correct updates and obsoletes headers.
o Removed the pre5378 disclaimer.
o Updated references.
o Removed the SPKI references from the document.
Authors' Addresses Authors' Addresses
Tobias Heer Tobias Heer
Hirschmann Automation and Control Albstadt-Sigmaringen University
Stuttgarter Strasse 45-51 Poststr. 6
Neckartenzlingen 72654 72458 Albstadt
Germany Germany
Email: tobias.heer@belden.com Email: heer@hs-albsig.de
Samu Varjonen Samu Varjonen
University of Helsinki University of Helsinki
Gustaf Haellstroemin katu 2b Gustaf Haellstroemin katu 2b
Helsinki Helsinki
Finland Finland
Email: samu.varjonen@helsinki.fi Email: samu.varjonen@helsinki.fi
 End of changes. 29 change blocks. 
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