Network Working Group A. Lindem Internet-Draft A. Oswal Intended status: Standards Track Redback Networks Expires: February 4, 2008 August 3, 2007 Bulk Registration Revocation in Mobile IPv4 draft-acee-mip4-bulk-revocation-00.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of 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. 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 February 4, 2008. Copyright Notice Copyright (C) The IETF Trust (2007). Lindem & Oswal Expires February 4, 2008 [Page 1] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Abstract This document describes an extension to Mobile IPv4 Registration Revocation (as described in RFC 3543) for a home or foreign agent to revoke mobile IP services for multiple bindings or visitors with a single registration revocation exchange. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Requirements notation . . . . . . . . . . . . . . . . . . 3 2. Registration Revocation Extensions and Messages . . . . . . . 4 2.1. Revocation Support Extension Changes . . . . . . . . . . . 4 2.2. Revocation Selection Extension . . . . . . . . . . . . . . 5 2.3. Registration Revocation Message Changes . . . . . . . . . 8 2.4. Registration Revocation Acknowledgment Message Changes . . 10 2.5. Replay Protection . . . . . . . . . . . . . . . . . . . . 11 3. Bulk Registration Revocation Overview . . . . . . . . . . . . 12 3.1. Home Agent Responsibilities . . . . . . . . . . . . . . . 12 3.2. Foreign Agent Responsibilities . . . . . . . . . . . . . . 12 3.3. Direct Co-located Node Responsibilities . . . . . . . . . 13 4. Security Considerations . . . . . . . . . . . . . . . . . . . 14 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 6. Normative References . . . . . . . . . . . . . . . . . . . . . 16 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . . 17 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 18 Intellectual Property and Copyright Statements . . . . . . . . . . 19 Lindem & Oswal Expires February 4, 2008 [Page 2] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 1. Introduction This document describes an extension to Mobile IPv4 Registration Revocation (as described in [REVOCATION]) for a home or foreign agent to revoke mobile IP services for multiple bindings or visitors with a single registration revocation exchange. 1.1. Requirements notation 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-KEYWORDS]. Lindem & Oswal Expires February 4, 2008 [Page 3] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 2. Registration Revocation Extensions and Messages The following changes are required for bulk revocation. 1. The revocation support extension will include a bit indicating whether or not the agent supports bulk revocation. 2. The Registration Revocation and Registration Revocation Acknowledgment will include a bit indicating whether or not the registration is a bulk registration. If so, the Home Agent Address will include a prefix rather than a specific mobile node's home address. Additionally, a previously reserved field will now include the prefix length. 3. A non-skippable revocation selection extension is added to further qualify bulk Registration Revocation. 2.1. Revocation Support Extension Changes The Mobile IP Revocation Support Extension indicates support of registration revocation, and so MUST be attached to a Registration Request or Registration Reply by any entity that wants to receive revocation messages. The extension is fully described in [REVOCATION]. This document includes an indication of whether or not bulk revocation is supported for this registration. Alternately, bulk revocation could be negotiated globally between the mobility agents using a mechanism beyond the scope of this specification. The format of the Revocation Support Extension is based on the Type- Length-Value Extension Format given in [MIP4] and is defined in [REVOCATION]. Changes are described below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length |I|B| Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Timestamp | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Revocation Support Extension Changes to the Revocation Support Extension are: Lindem & Oswal Expires February 4, 2008 [Page 4] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Type 137 - Unchanged from [REVOCATION] Length Unchanged from [REVOCATION] Timestamp Unchanged from [REVOCATION] 'I' Bit Unchanged from [REVOCATION] 'B' Bit This bit is set to '1' by a mobility agent to indicate that bulk revocation (as specified herein) is applicable to this binding. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. The Mobile IP Revocation Support Extension may appear in either a Registration Request or Registration Reply. 'B' bit or bulk revocation support will only be in force when negotiated by both agents through either the setting of the 'B' bit or a global mechanism beyond the scope of this specification. 2.2. Revocation Selection Extension The Mobile IP Revocation Selection Extension is used to further qualify bulk revocation (as described herein). It is only applicable to the Registration Revocation and Registration Revocation Acknowledgement messages. The format of the Revocation Selection Extension is based on the Type-Length-Sub-Type-Value Short Extension Format described in [MIP4]. It further qualifies the selection of revoked registrations specified herein. 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Length | Sub-Type | Data .... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ o Dependent on Sub-Type o Revocation Selection Extension Lindem & Oswal Expires February 4, 2008 [Page 5] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+ | Reserved | +-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Starting Home IP Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Ending Home IP Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Start/End Home IP Address Sub-Type Variable Format 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+ | Regular ... +-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ ... Expression | o Variable Length Regular Expression o | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ NAI Regular Expression Sub-Type Variable Format 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 Tunnel Encapsulation Sub-Type +-+-+-+-+-+-+-+-+ | Protocol ID | +-+-+-+-+-+-+-+-+ Tunnel Encapsulation Sub-Type Variable Format Revocation Selection Extension fields include: Lindem & Oswal Expires February 4, 2008 [Page 6] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Type Non-skippable = TBD Length Depends on the selection algorithm specified. Sub-Type Indicates the type of additional selection specified: 1 - Start/End Home IP Address Indicates the TLV contains a starting and ending home IP address used to further qualify registration selection. For this sub-type, the length of the TLV will be 10 bytes. 2 - NAI Regular Expression Indicates the TLV contains a regular expression applied to the NAI (Network Access Identifier). This field is only limited by the single byte length. Hence, it can be up to 254 octets in length given that the sub-type takes 1 octet. 3 - Encapsulation Indicates the TLV contains a tunnel encapsulation protocol identifier. This indicates that the bulk revocation only applies to registrations using the specified tunnel encapsulation. For this sub-type, the length of the TLV will be 2 bytes. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. Starting Home IP Address The starting address in a range of IP home addresses whose registrations are to be revoked. Ending Home IP Address The ending address in a range of IP home addresses whose registrations are to be revoked. NAI Regular Expression A regular expression to be matched against the Network Address Identifier (NAI) for registration to determine which registrations are to be revoked. Refer to [NAI] for information on Mobile IP Network Access Identifiers. Refer to [REG-EXPR] for information on regular expressions. Lindem & Oswal Expires February 4, 2008 [Page 7] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Protocol ID The protocol ID corresponding to the tunnel encapsulation: 94 IP-in-IP encapsulation [IP-IN-IP] 47 Generic Routing Encapsulation (GRE) [GRE] 55 Minimal IP Encapsulation [MIN-IP] The Mobile IP revocation selection extension may appear in either a Registration Revocation or Registration Revocation Acknowledgement message. 2.3. Registration Revocation Message Changes The Registration Revocation Message is fully described in [REVOCATION]. The UDP header is followed by the Mobile IP fields which are repeated herein with the changes described below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Reserved |A|I|B| Reserved| Prefix Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Home Address/Prefix | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Home Domain Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Foreign Domain Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Revocation Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extensions... +-+-+-+-+-+-+-+-+-+-+-+-+- | Authenticator... +-+-+-+-+-+-+-+-+-+-+-+-+- Registration Revocation Message Changes Changes to the Registration Revocation message are: Lindem & Oswal Expires February 4, 2008 [Page 8] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Type 7 - Unchanged from [REVOCATION] 'I' Bit Unchanged from [REVOCATION] 'A' Bit Unchanged from [REVOCATION] 'B' Bit This bit is set to '1' by a mobility agent to indicate that this revocation message is a request for bulk revocation. Bulk revocation may apply to one or many registrations. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. Prefix Length The prefix length which, when combined with the home prefix specifies which registrations are to be revoked. If bulk revocation is requested (as specified by the 'B' bit) and this field is zero, the Registration Revocation applies to all registrations for which bulk revocation was previously negotiated using the Revocation Support Extension or a global mechanism beyond the scope of this specification. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. Home Address/Prefix If bulk revocation is requested ('B' bit set to '1'), this field is combined with the prefix length to select one or more registrations to be revoked. If bulk revocation is not requested ('B' bit set to '0'), this field specifies the home IP address of the mobile node whose registration is being revoked. Home Domain Address Unchanged from [REVOCATION] Foreign Domain Address Unchanged from [REVOCATION] Revocation ID Unchanged from [REVOCATION] The Registration Revocation message is processed as before only now Lindem & Oswal Expires February 4, 2008 [Page 9] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 it can be applied to one or more active registrations between the mobility agents. It must be authenticated as specified in [REVOCATION]. 2.4. Registration Revocation Acknowledgment Message Changes The Registration Revocation Acknowledgment Message is fully described in [REVOCATION]. The UDP header is followed by the Mobile IP fields which are repeated herein with the changes described below: 0 1 2 3 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Type | Reserved |I|B| Reserved | Prefix Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Home Address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Revocation Identifier | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Extensions... +-+-+-+-+-+-+-+-+-+-+-+-+- | Authenticator... +-+-+-+-+-+-+-+-+-+-+-+-+- Registration Revocation Message Changes Changes to the Registration Revocation Acknowledgement message are: Type 15 - Unchanged from [REVOCATION] 'I' Bit Unchanged from [REVOCATION] 'B' Bit This bit is set to '1' by a mobility agent to indicate successful revocation of at least one registration in response to the bulk revocation request. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. Lindem & Oswal Expires February 4, 2008 [Page 10] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Prefix Length The prefix length which, when combined with the home prefix specifies which registrations were revoked. The prefix length MUST match the length specified on the corresponding Registration Revocation message. Reserved Reserved for future use. MUST be set to 0 on sending, MUST be ignored on receiving. Home Address/Prefix If bulk revocation is requested ('B' bit set to '1'), this field is combined with the prefix length to select one or more registrations to be revoked. If bulk revocation is not requested ('B' bit set to '0"), this field specifies the home IP address of the mobile node whose registration is being revoked. It MUST match the home address/prefix specified on the previous Registration Revocation message. Revocation ID Unchanged from [REVOCATION] A Registration Revocation Acknowledgment message MUST be sent in response to a valid and authenticated registration revocation message as specified in [REVOCATION]. 2.5. Replay Protection Replay protection proceeds in much the same way as described in [REVOCATION]. However, when assuring that the message is not a replayed message, the mobility agent must check the timestamp to assure it is greater than the timestamp received from the most recently received Mobility Revocation Support extension from the agent. One way to support this is to maintain the most recent per- peer timestamp for peer mobility agents. For co-located mobile nodes, there normally will be only one active registration (situations where there are many are beyond the scope of this document). Lindem & Oswal Expires February 4, 2008 [Page 11] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 3. Bulk Registration Revocation Overview Bulk Registration Revocation processing is identical to Registration Revocation as described in [REVOCATION] except for following differences: 1. When the Registration Request is received, bulk revocation support is negotiated through the setting of the B-Bit in the Revocation Support extension. This negotiation should not preclude global bulk revocation negotiation between mobility agents. However, such support is beyond the scope of this document. 2. When a mobility agent processes a bulk Registration Revocation, it may apply to multiple registrations. 3. The replay protection validation will now use the timestamp in the most recent Revocation Support Extension from the sending agent. This is described in Section 2.5. 3.1. Home Agent Responsibilities Home Agent responsibilities are identical to [REVOCATION] except as noted above. In situations where a single event may apply to multiple registrations (or bindings on the Home Agent), a bulk revocation may be sent in lieu of multiple revocations. A non- exhaustive list of events that may benefit from bulk revocation includes: 1. Graceful shutdown of the home agent (HA) instance 2. Policy changes that preclude communication with the Foreign Agent (FA) 3. Withdrawn of the Home Agent local address from service 4. Home Address Pool deletion or change 5. Other policy change resulting in multiple registrations being revoked 3.2. Foreign Agent Responsibilities Foreign Agent responsibilities are identical to [REVOCATION] except as noted above. In situations where a single event may apply to multiple registrations (or visitors on the Foreign Agent), a bulk Lindem & Oswal Expires February 4, 2008 [Page 12] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 revocation may be sent in lieu of multiple revocations. A non- exhaustive list of events that may benefit from bulk revocation includes: 1. Graceful shutdown of the foreign agent (FA) instance 2. Policy changes that preclude communication with the Home Agent (HA) 3. Withdrawn of the Care-of-Address (CoA) from service 4. Other policy change resulting in multiple registrations being revoked 3.3. Direct Co-located Node Responsibilities In general, bulk revocation is not the useful to a direct co-located node since it will usually only have single registration with a home agent. Hence, there is really no reason for a direct co-located to negotiate bulk revocation in the first place by setting the B-Bit in the Revocation Support Extension appending to its initial registration. However, this specification does not preclude support and a direct co-located node negotiating bulk revocation must support bulk revocation requests. Lindem & Oswal Expires February 4, 2008 [Page 13] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 4. Security Considerations Security is basically unchanged from [REVOCATION] with the exception that replay protection will be based on the most recent registration revocation received from the peer (as described in Section 2.5). As with [REVOCATION], all message exchanges related to revocation MUST be protected by either a valid authenticator as specified in [MIP4]. For communications between mobility agents, FA-HA authentication or a mechanism at least as secure, e.g. IPsec, is required. For communication between a home agent and a direct co-located mobile node, MN-HA authentication or a mechanism at least as secure is required. In this context, all message exchanges relating to revocation include Registration Revocations, Registration Revocation Acknowledgments, Registration Requests including the Revocation Support Extension, and Registration Replies including the Revocation Support Extension. Lindem & Oswal Expires February 4, 2008 [Page 14] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 5. IANA Considerations A non-skippable extension value is needed for the Revocation Selection Extension. This should be allocated from the "Extensions appearing in Mobile IP messages" number space in the "Mobile IPv4 Numbers". Also, a new sub-registry is required for the sub-types for this extension. Initially, it will have the following values: 1 - Start/End Home IP Address Indicates the TLV contains a starting and ending home IP address used to further qualify registration selection. 2 - NAI Regular Expression Indicates the TLV contains a regular expression applied to the NAI (Network Access Identifier). 3 - Encapsulation Indicates the TLV contains a tunnel encapsulation protocol identifier. Refer to Section 2.2 for more information. Lindem & Oswal Expires February 4, 2008 [Page 15] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 6. Normative References [GRE] Farinacci, D., Li, T., Meyer, D., and P. Traina, "Generic Routing Encapsulation", RFC 2784, March 2000. [IP-IN-IP] Perkins, C., "IP Encapsulation within IP", RFC 2003, October 1996. [MIN-IP] Perkins, C., "Minimal Encapsulation within IP", RFC 2004, October 1996. [MIP4] Perkins, C., "IP Mobility Support for IPv4", RFC 3344, August 2002. [NAI] Johansson, F. and T. Johannsson, "Mobile IPv4 Extension for Carrying Network Access Identifiers", RFC 3846, June 2004. [REG-EXPR] Institute of Electrical and Electronix Engineers, "Information Technology - Portable Operation System Interface (POSIX) - Part 2: Shell and Variables (Vol. 1)", IEEE 1003.3, 1992. [REVOCATION] Chandra, M. and S. Glass, "Registration Revocation in Mobile IPv4", RFC 3543, August 2003. [RFC-KEYWORDS] Bradner, S., "Key words for use in RFC's to Indicate Requirement Levels", RFC 2119, March 1997. Lindem & Oswal Expires February 4, 2008 [Page 16] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Appendix A. Acknowledgments The RFC text was produced using Marshall Rose's xml2rfc tool. Lindem & Oswal Expires February 4, 2008 [Page 17] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Authors' Addresses Acee Lindem Redback Networks 102 Carric Bend Court Cary, NC 27519 USA Email: acee@redback.com Anand Oswal Redback Networks 300 Holger San Jose, CA 95134 USA Email: aoswal@redback.com Lindem & Oswal Expires February 4, 2008 [Page 18] Internet-Draft Mobile IPv4 Bulk Revocation August 2007 Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. 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