Network A. Antony Internet-Draft secunet Intended status: Standards Track P. Kerpan Expires: 9 January 2025 Cohesive Networks P. Wouters Aiven 8 July 2024 IKEv2 support for specifying a Delete notify reason draft-pwouters-ipsecme-delete-info-02 Abstract This document defines the DELETE_REASON Notify Message Status Type Payload for the Internet Key Exchange Protocol Version 2 (IKEv2) to support adding a reason for the deletion of the IKE or Child SA(s). Status of This Memo 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). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://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." This Internet-Draft will expire on 9 January 2025. Copyright Notice Copyright (c) 2024 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 (https://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 Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Antony, et al. Expires 9 January 2025 [Page 1] Internet-Draft IKEv2 support for specifying a Delete no July 2024 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 2 1.2. Payload Format . . . . . . . . . . . . . . . . . . . . . 2 2. Delete Reason Usage . . . . . . . . . . . . . . . . . . . . . 3 3. DELETE_REASON Notify Status Message Payload format . . . . . 3 4. Initial Delete Reason Registry Values . . . . . . . . . . . . 4 5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5 6.1. Delete Reason Notify . . . . . . . . . . . . . . . . . . 5 6.2. Delete Reason Registry . . . . . . . . . . . . . . . . . 5 6.3. Designated Expert Advise . . . . . . . . . . . . . . . . 6 7. Implementation Status . . . . . . . . . . . . . . . . . . . . 6 7.1. Libreswan . . . . . . . . . . . . . . . . . . . . . . . . 7 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 8.1. Normative References . . . . . . . . . . . . . . . . . . 7 8.2. Informative References . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8 1. Introduction The IKEv2 [RFC7296] protocol supports sending a Delete Notify message, but this message cannot convey the reason why a particular Child SA or IKE SA is being deleted. It can be useful to know why a certain IPsec IKE SA or Child SA was deleted by the peer. Sometimes, when the peer's operator notices a specific SA is down, they have no idea whether this is permanent or temporary problem, and have no idea how long an outage might last. The DELETE_REASON Notify message can be added to any exchange that contains a Delete (42) payload specifying an estimated duration and reason. The initial Delete Reason values are specified in Section 4. 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. 1.2. Payload Format All multi-octet fields representing integers are laid out in big endian order (also known as "most significant byte first", or "network byte order"). Antony, et al. Expires 9 January 2025 [Page 2] Internet-Draft IKEv2 support for specifying a Delete no July 2024 2. Delete Reason Usage Whenever an IKE peer wishes to relay the reason for why it is deleting an IKE SA or one or more IPsec SAs, it MAY include a DELETE_REASON notify payload. The notify payload contains a Reason Type and an optional Reason Message Text. A DELETE_REASON payload MUST be ignored if the exchange does not contain a Delete payload. If multiple Delete payloads are present, the DELETE_REASON message applies to all of these. If separate different reasons should be conveyed for different Child SAs or IKE SA, those Delete messages and their accompanied DELETE_REASON messages should be sent in separate Informational Exchange messages. 3. DELETE_REASON Notify Status Message Payload format 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 +-+-----------------------------+-------------------------------+ | Next Payload |C| RESERVED | Payload Length | +---------------+---------------+-------------------------------+ | Protocol ID | SPI Size | Notify Message Type | +---------------+---------------+-------------------------------+ | Downtime | Delete Reason Type | +-------------------------------+-------------------------------+ ~ Delete Reason Text ~ +-------------------------------+-------------------------------+ * (C)ritical bit - MUST be 0. * Protocol ID (1 octet) - MUST be 0. MUST be ignored if not 0. * SPI Size (1 octet) - MUST be 0. MUST be ignored if not 0. * Notify Status Message Type (2 octets) - set to [TBD1] * Downtime (2 octets) A value in seconds for the expected downtime. 0 means unspecified. * Delete Reason Type (2 octets) - See Section 4 * Delete Reason Text - May be empty. Otherwise a non-NULL terminated UTF-8 or ASCII text. Antony, et al. Expires 9 January 2025 [Page 3] Internet-Draft IKEv2 support for specifying a Delete no July 2024 4. Initial Delete Reason Registry Values The following table describes the initial IKEv2 Notify Message Delete Reason Registry values: UNSPECIFIED There is no matching Type. Details should be in the Delete Reason Text field SERVICE_SHUTDOWN The IKE service is being shut down SERVICE_RESTART The IKE service is being restarted HOST_SHUTDOWN The host running the IKE service is being shut down HOST_RESTART The host running the IKE service is being restarted CONFIGURATION_CHILD_REMOVED The Child SA was removed from the peer's configuration CONFIGURATION_IKE_REMOVED The IKE SA was removed from the peer's configuration ADMINISTRATIVELY_DOWN The SA was brought down by the operator IDLE_TIMEOUT The SA was inactive and brought down automatically by the system INITIAL_CONTACT_REPLACED A new IKE SA with this peer was established that signaled INITIAL_CONTACT SIMULTANEOUS_REKEY The peers ended up rekeying at once, and this SA lost in favour of the other RE_AUTHENTICATED A new IKE SA with this peer was established for re- authentication purposes REDIRECTION_ACCEPTED The redirection request was accepted and established, obsoleting this old SA LIFETIME_EXCEEDED The SA reached its local lifetime counter (bytes or seconds or packets) and was not rekeyed in time Antony, et al. Expires 9 January 2025 [Page 4] Internet-Draft IKEv2 support for specifying a Delete no July 2024 5. Security Considerations Any timing information and reason should be treated as an informational "best effort" message from the peer's operator. A DELETE_REASON message SHOULD NOT change the behaviour of the IKE implementation other than logging the message or triggering an informational or alert message. As with all received free-form text data, the receiver MUST treat the DELETE_REASON notify data as untrusted. It SHOULD strip or replace any characters not deemd regular text, for example the dollar sign ($), braces, backticks and backslashes. The Reason Message MUST NOT be assumed to be safe to display. It MUST NOT be assumed to be NULL terminated, which means common string operations such as strlen() MUST NOT be used without precautions. After the data has been processed and confirmed safe, it can be used for logging or as messages in notification systems. 6. IANA Considerations This document adds one new IKEv2 Notify Message Status Type value and one new IKEv2 registry. 6.1. Delete Reason Notify The following Notify Message Status is added: Value IKEv2 Notify Message Status Type Reference ----- ------------------------------ --------------- [TBD1] DELETE_REASON [this document] Figure 1 6.2. Delete Reason Registry This document requests IANA create the IKEv2 Notify Message Delete Reason Registry under the Internet Key Exchange Version 2 (IKEv2) Parameters Registry with the following fields and initial values: Antony, et al. Expires 9 January 2025 [Page 5] Internet-Draft IKEv2 support for specifying a Delete no July 2024 Type Reason Name Reference ----- ---------------------------- ------------------- 0 UNSPECIFIED [this document] 1 SERVICE_SHUTDOWN [this document] 2 SERVICE_RESTART [this document] 3 HOST_SHUTDOWN [this document] 4 HOST_RESTART [this document] 5 CONFIGURATION_CHILD_REMOVED [this document] 6 CONFIGURATION_IKE_REMOVED [this document] 7 ADMINISTRATIVELY_DOWN [this document] 8 IDLE_TIMEOUT [this document] 9 INITIAL_CONTACT_REPLACED [this document] 10 SIMULTANEOUS_REKEY [this document] 11 RE_AUTHENTICATED [this document] 12 REDIRECTION_ACCEPTED [this document] 13 LIFETIME_EXCEEDED [this document] 14-255 Unassigned 256 - 65279 Unassigned 65280 - 65535 Private Use Values Figure 2 The registry values 0-255 are assigned using the Standards Track registration policy. The registry values 256-65279 are assigned using the First Come First Servce registration policy. The registry values 65280-65535 are reserved for Private Use and Experimental Use 6.3. Designated Expert Advise The Designated Expert (DE) for this new registry should verify that the entry makes sense within the IKEv2 protocol context and is distinct from existing entries in the registry. 7. Implementation Status [Note to RFC Editor: Please remove this section and the reference to [RFC6982] before publication.] This section records the status of known implementations of the protocol defined by this specification at the time of posting of this Internet-Draft, and is based on a proposal described in [RFC7942]. The description of implementations in this section is intended to assist the IETF in its decision processes in progressing drafts to Antony, et al. Expires 9 January 2025 [Page 6] Internet-Draft IKEv2 support for specifying a Delete no July 2024 RFCs. Please note that the listing of any individual implementation here does not imply endorsement by the IETF. Furthermore, no effort has been spent to verify the information presented here that was supplied by IETF contributors. This is not intended as, and must not be construed to be, a catalog of available implementations or their features. Readers are advised to note that other implementations may exist. According to [RFC7942], "this will allow reviewers and working groups to assign due consideration to documents that have the benefit of running code, which may serve as evidence of valuable experimentation and feedback that have made the implemented protocols more mature. It is up to the individual working groups to use this information as they see fit". Authors are requested to add a note to the RFC Editor at the top of this section, advising the Editor to remove the entire section before publication, as well as the reference to [RFC7942]. 7.1. Libreswan Organization: The Libreswan Project Name: https://libreswan.org/ Description: An initial IKE implementation using the Private Use value 40960 for the Notify payload Level of maturity: Beta Coverage: Implements the draft's example reasons Licensing: GPLv2 Implementation experience: TBD Contact: Libreswan Development: swan-dev@libreswan.org 8. References 8.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Antony, et al. Expires 9 January 2025 [Page 7] Internet-Draft IKEv2 support for specifying a Delete no July 2024 [RFC7296] Kaufman, C., Hoffman, P., Nir, Y., Eronen, P., and T. Kivinen, "Internet Key Exchange Protocol Version 2 (IKEv2)", STD 79, RFC 7296, DOI 10.17487/RFC7296, October 2014, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . 8.2. Informative References [RFC6982] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: The Implementation Status Section", RFC 6982, DOI 10.17487/RFC6982, July 2013, . [RFC7942] Sheffer, Y. and A. Farrel, "Improving Awareness of Running Code: The Implementation Status Section", BCP 205, RFC 7942, DOI 10.17487/RFC7942, July 2016, . Authors' Addresses Antony Antony secunet Security Networks AG Email: antony.antony@secunet.com Patrick Kerpan Cohesive Networks Email: pjkerpan@cohesive.net Paul Wouters Aiven Email: paul.wouters@aiven.io Antony, et al. Expires 9 January 2025 [Page 8]