--- 1/draft-ietf-hip-cert-10.txt 2011-03-09 13:17:28.000000000 +0100 +++ 2/draft-ietf-hip-cert-11.txt 2011-03-09 13:17:28.000000000 +0100 @@ -1,63 +1,58 @@ Host Identity Protocol Heer Internet-Draft Communication and Distributed Updates: 5201 (if approved) Systems, RWTH Aachen University Intended status: Experimental Varjonen Expires: September 10, 2011 Helsinki Institute for Information Technology March 9, 2011 Host Identity Protocol Certificates - draft-ietf-hip-cert-10 + draft-ietf-hip-cert-11 Abstract The CERT parameter is a container for digital certificates. It is used for carrying these certificates in Host Identity Protocol (HIP) control packets. This document specifies the certificate parameter and the error signaling in case of a failed verification. Additionally, this document specifies the representations of Host - Identity Tags in X.509.v3 and SPKI certificates. + Identity Tags in X.509 version 3 (v3) and SPKI certificates. The concrete use of certificates including how certificates are obtained, requested, and which actions are taken upon successful or failed verification are specific to the scenario in which the certificates are used. Hence, the definition of these scenario- specific aspects are left to the documents that use the CERT parameter. + This document updates RFC 5201. + Status of this Memo - This Internet-Draft is submitted to IETF in full conformance with the + This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering - Task Force (IETF), its areas, and its working groups. Note that - other groups may also distribute working documents as Internet- - Drafts. + Task Force (IETF). Note that other groups may also distribute + working documents as Internet-Drafts. The list of current Internet- + Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - The list of current Internet-Drafts can be accessed at - http://www.ietf.org/ietf/1id-abstracts.txt. - - The list of Internet-Draft Shadow Directories can be accessed at - http://www.ietf.org/shadow.html. - This Internet-Draft will expire on September 10, 2011. Copyright Notice - Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of @@ -55,21 +50,21 @@ document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as - described in the BSD License. + described in the Simplified BSD License. This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November 10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s) controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative works of it may not be created outside the IETF Standards Process, except to format @@ -85,22 +80,23 @@ namespace based on asymmetric cryptography. The identity of each host is derived from a public key, allowing hosts to digitally sign data and issue certificates with their private key. This document specifies the CERT parameter, which is used to transmit digital certificates in HIP. It fills the placeholder specified in Section 5.2 of [RFC5201], and thus, updates [RFC5201]. 1.1. Requirements Language 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 [RFC2119]. + "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and + "OPTIONAL" in this document are to be interpreted as described in RFC + 2119 [RFC2119]. 2. CERT Parameter The CERT parameter is a container for certain types of digital certificates. It does not specify any certificate semantics. However, it defines supplementary parameters that help HIP hosts to transmit semantically grouped CERT parameters in a more systematic way. The specific use of the CERT parameter for different use cases is intentionally not discussed in this document because it is specific to a concrete use case. Hence, the use of the CERT @@ -166,80 +162,80 @@ The certificates MUST use the algorithms defined in [RFC5201] as the signature and hash algorithms. The following certificate types are defined: +--------------------------------+-------------+ | Cert format | Type number | +--------------------------------+-------------+ | Reserved | 0 | - | X.509.v3 | 1 | + | X.509 v3 | 1 | | SPKI | 2 | - | Hash and URL of X.509.v3 | 3 | + | Hash and URL of X.509 v3 | 3 | | Hash and URL of SPKI | 4 | - | LDAP URL of X.509.v3 | 5 | + | LDAP URL of X.509 v3 | 5 | | LDAP URL of SPKI | 6 | - | Distinguished Name of X.509.v3 | 7 | + | Distinguished Name of X.509 v3 | 7 | | Distinguished Name of SPKI | 8 | +--------------------------------+-------------+ 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 certificates and the handling procedures are defined in - [RFC5280]. The wire format for X.509.v3 is Distinguished Encoding + X.509 v3 and in Simple Public Key Infrastructure (SPKI) certificates. + X.509 v3 certificates and the handling procedures are defined in + [RFC5280]. The wire format for X.509 v3 is Distinguished 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 as defined in [RFC5996] Section 3.6. Using hash and URL encodings results in smaller HIP control packets, but requires the receiver to resolve the URL or check a local cache against the hash. LDAP URL encodings (5 and 6) are used as defined in [RFC4516]. Using LDAP URL encoding results in smaller HIP control packets but requires the receiver to retrieve the certificate or check a local cache against the URL. Distinguished name (DN) encodings (7 and 8) are used as defined in [RFC4514]. Using the DN encoding results in smaller HIP control packets, but requires the receiver to retrieve the certificate or check a local cache against the DN. -3. X.509.v3 Certificate Object and Host Identities +3. X.509 v3 Certificate Object and Host Identities - HITs can represent an issuer, a subject, or both in x.509.v3. HITs + HITs can represent an issuer, a subject, or both in x.509 v3. HITs are represented as IPv6 addresses as defined in [RFC4843]. When Host Identifier ( HI ) is used to sign the certificate the respective HIT MUST be placed in to the Issuer Alternative Name (IAN) extension using the GeneralName form iPAddress as defined in [RFC5280]. When the certificate is issued for a HIP host, identified by a HIT and HI, the respective HIT MUST be placed in to the Subject Alternative Name (SAN) extension using the GeneralName form iPAddress and the full HI is presented as the subjects public key info as defined in [RFC5280]. The following examples illustrate how HITs are presented as issuer - and subject in the X.509.v3 extension alternative names. + and subject in the X.509 v3 extension alternative names. Format of X509v3 extensions: X509v3 Issuer Alternative Name: IP Address:hit-of-issuer X509v3 Subject Alternative Name: IP Address:hit-of-subject Example X509v3 extensions: X509v3 Issuer Alternative Name: IP Address:2001:14:6cf:fae7:bb79:bf78:7d64:c056 X509v3 Subject Alternative Name: IP Address:2001:1C:5a14:26de:a07C:385b:de35:60e3 - Appendix B shows a full example X.509.v3 certificate with HIP + Appendix B shows a full example X.509 v3 certificate with HIP content. As another example, consider a managed Public Key Infrastructure (PKI) environment in which the peers have certificates that are anchored in (potentially different) managed trust chains. In this scenario, the certificates issued to HIP hosts are signed by intermediate Certificate Authorities (CAs) up to a root CA. In this example, the managed PKI environment is neither HIP aware, nor can it be configured to compute HITs and include them in the certificates. @@ -265,21 +261,21 @@ As an example the Host Identity Tag of a host is expressed as follows: Format: (hash hit hit-of-host) Example: (hash hit 2001:13:724d:f3c0:6ff0:33c2:15d8:5f50) Appendix A shows a full example SPKI certificate with HIP content. 5. Revocation of Certificates - Revocation of X.509.v3 certificates is handled as defined in Section + Revocation of X.509 v3 certificates is handled as defined in Section 5 of [RFC5280]. Revocation of SPKI certificates is handled as defined in Section 5 of [RFC2693]. 6. Error signaling If the Initiator does not send the certificate that the Responder requires the Responder may take actions (e.g. reject the connection). The Responder MAY signal this to the Initiator by sending a HIP NOTIFY message with NOTIFICATION parameter error type @@ -328,21 +324,21 @@ fragmentation allows, for example sending of fragments in wrong order and skipping some fragments to delay or stall packet processing by the victim in order to use resources (e.g. CPU or memory). Hence, hosts SHOULD implement mechanisms to discard certificate groups with outstanding certificates if state space is scarce. Checking of the URL and LDAP entries might allow DoS attacks, where the target host may be subjected to bogus work. Security considerations for SPKI certificates are discussed in - [RFC2693] and for X.509.v3 in [RFC5280] + [RFC2693] and for X.509 v3 in [RFC5280] 9. Acknowledgements The authors would like to thank A. Keranen, D. Mattes, M. Komu and T. Henderson for the fruitful conversations on the subject. D. Mattes most notably contributed the non-HIP aware use case in Section 3. 10. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate @@ -412,21 +408,21 @@ (hash sha1 |h5fC8HUMATTtK0cjYqIgeN3HCIMA|) |u8NTRutINI/AeeZgN6bngjvjYPtVahvY7MhGfenTpT7MCgBy NoZglqH5Cy2vH6LrQFYWx0MjWoYwHKimEuBKCNd4TK6hrCyAI CIDJAZ70TyKXgONwDNWPOmcc3lFmsih8ezkoBseFWHqRGISIm MLdeaMciP4lVfxPY2AQKdMrBc=| ) ) Appendix B. 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: Data: Version: 3 (0x2) Serial Number: 0 (0x0) Signature Algorithm: sha1WithRSAEncryption Issuer: CN=2001:1e:d709:1980:5c6a:bb0c:7650:a027 Validity Not Before: Jun 22 13:39:32 2010 GMT Not After : Jul 2 13:39:32 2010 GMT @@ -542,20 +538,24 @@ o Fixing boilerplate. Changes from version 09 to 10: o IANA considerations updated based on the IANA review. o Updates based on the hip-chairs review. o Updates based on the Gen-ART review. + Changes from version 10 to 11: + + o Fixed the nits. + Authors' Addresses Tobias Heer Communication and Distributed Systems, RWTH Aachen University Ahornstrasse 55 Aachen Germany Phone: +49 241 80 20 776 Email: heer@cs.rwth-aachen.de