Point-to-Point Protocol (PPP) Vendor Protocol
The information below is for an old version of the document that is already published as an RFC.
This is an older version of an Internet-Draft that was ultimately published as RFC 3772.
|Authors||James D. Carlson , Richard Winslow|
|Last updated||2013-03-02 (Latest revision 2004-02-12)|
|RFC stream||Internet Engineering Task Force (IETF)|
|Additional resources||Mailing list discussion|
|IESG||IESG state||RFC 3772 (Proposed Standard)|
|Responsible AD||Dr. Thomas Narten|
|Send notices to||(None)|
Network Working Group James Carlson INTERNET-DRAFT Sun Microsystems Expires August 2004 Richard Winslow L-3 Communications February 2004 PPP Vendor Protocol <draft-ietf-pppext-vendor-protocol-02.txt> Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. 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. Abstract The Point-to-Point Protocol (PPP) defines a Link Control Protocol (LCP) and a method for negotiating the use of multi-protocol traffic over point-to-point links. PPP Vendor Extensions adds vendor- specific general-purpose Configuration Option and Code numbers. This document extends these features to cover vendor-specific Network, Authentication, and Control Protocols. Carlson and Winslow expires August 2004 [Page 1] INTERNET-DRAFT PPP Vendor Protocol February 2004 1. Introduction PPP's  Vendor Extensions  defines a general-purpose mechanism for the negotiation of various vendor-proprietary options and exten- sions to the kinds of control messages that may be sent via the Code field. Some implementors may want to define proprietary network and control protocols in addition to the already-described features. While it would be possible for such an implementor to use the existing LCP Vendor-Specific Option to enable the use of the proprietary protocol, this staged negotiation (enable via LCP, then negotiate via some locally-assigned protocol number) suffers from at least three prob- lems: First, because it would be in LCP, the negotiation of the use of the protocol would begin before identification and authentication of the peer had been done. This complicates the security analysis of the feature and constrains the way in which the protocol might be deployed. Second, where compulsory tunneling is in use, the system performing the initial LCP negotiation may be unrelated to the system that uses the proprietary protocol. In such a scenario, enabling the protocol at LCP time would require either LCP renegotiation or support of the proprietary protocol in the initial negotiator, both of which raise deployment problems. Third, the fact that any protocol negotiated via such a mechanism would necessarily use a protocol number that is not assigned by IANA complicates matters for diagnostic tools used to monitor the datas- tream. Having a fixed number allows these tools to display such pro- tocols in a reasonable, albeit limited, format. A cleaner solution is thus to define a set of vendor-specific proto- cols, one each in each of the four protocol number ranges defined by . This specification reserves the following values: Value (in hex) Protocol Name 005b Vendor-Specific Network Protocol (VSNP) 405b Vendor-Specific Protocol (VSP) 805b Vendor-Specific Network Control Protocol (VSNCP) c05b Vendor-Specific Authentication Protocol (VSAP) 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 BCP 14 . Carlson and Winslow expires August 2004 [Page 2] INTERNET-DRAFT PPP Vendor Protocol February 2004 2. PPP Vendor-Specific Network Control Protocol (VSNCP) The Vendor-Specific Network Control Protocol (VSNCP) is responsible for negotiating the use of the Vendor-Specific Network Protocol (VSNP). VSNCP uses the same packet exchange and option negotiation mechanism as LCP, but with a different set of options. VSNCP packets MUST NOT be exchanged until PPP has reached the Network-Layer Protocol phase. Any VSNCP packets received when not in that phase MUST be silently ignored. If a VSNCP packet with an unrecognized OUI is received, an LCP Protocol-Reject SHOULD be sent in response. The network layer data, carried in VSNP packets, MUST NOT be sent unless VSNCP is in Opened state. If a VSNP packet is received when VSNCP is not in Opened state and LCP is Opened, the implementation MAY respond using LCP Protocol-Reject. 2.1. VSNCP Packet Format Exactly one VSNCP packet is carried in the PPP Information field, with the PPP Protocol field set to hex 805b (VSNCP). A summary of the VSNCP packet format is shown below. The fields are transmitted from left to right. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Code | Identifier | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OUI | Data ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Code Only LCP Code values 1 through 7 (Configure-Request, Configure-Ack, Configure-Nak, Configure-Reject, Terminate-Request, Terminate-Ack, and Code-Reject) are used. All other codes SHOULD result in a VSNCP Code-Reject reply. Identifier and Length These are as documented for LCP. Carlson and Winslow expires August 2004 [Page 3] INTERNET-DRAFT PPP Vendor Protocol February 2004 OUI This three-octet field contains the vendors' Organizationally Unique Identifier. The bits within the octet are in canonical order, and the most significant octet is transmitted first. See Section 5 below for more information on OUI values. Data This field contains data in the same format as for the corresponding LCP Code numbers. 2.2. VSNP Packet Format When VSNCP is in Opened state, VSNP packets may be sent by setting the PPP Protocol field to hex 005b (VSNP) and placing the vendor- specific data in the PPP Information field. No restrictions are placed on this data. 3. PPP Vendor-Specific Protocol (VSP) The Vendor-Specific Protocol (VSP) is intended for use in situations where the implementation of a complete Network Layer Protocol is unnecessary, or where per-link signaling is required (see Section 7 below). VSP packets MUST NOT be sent until PPP has reached either Network- Layer Protocol or Authentication phase. VSP packets received before those phases MUST be silently ignored. Once the proper phase has been reached, a VSP packet containing an unrecognized OUI value SHOULD be returned using LCP Protocol-Reject. Exactly one VSP packet is carried in the PPP Information field, with the PPP Protocol field set to 405b (VSP). A summary of the VSP packet format is shown below. The fields are transmitted from left to right. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Magic-Number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OUI | Reserved | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Data ... +-+-+-+ Carlson and Winslow expires August 2004 [Page 4] INTERNET-DRAFT PPP Vendor Protocol February 2004 Magic-Number The four-octet Magic-Number field is used to detect looped-back links. If the Magic-Number Option was not negotiated by LCP, then this field MUST be set to 0. Implementation of the LCP Magic-Number Option is RECOMMENDED. OUI This three-octet field contains the vendors' Organizationally Unique Identifier. The bits within the octet are in canonical order, and the most significant octet is transmitted first. See Section 5 below for more information on OUI values. Reserved Reserved for future definition. Must be zero on transmit and ignored on reception. Data Vendor-specific data. 4. PPP Vendor-Specific Authentication Protocol (VSAP) The Vendor-Specific Authentication Protocol (VSAP) is used in two ways. First, it is used with the LCP Authentication Option in order to negotiate the use of a vendor-specific authentication protocol to be used during the PPP Authentication phase. Second, it is used in the PPP Protocol field to carry those proprietary authentication mes- sages during PPP Authentication phase. 4.1. VSAP Authentication Option Format This option is used in LCP Configure-Request, -Ack, -Nak, and -Reject messages. 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 | Authentication-Protocol | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OUI | Data ... +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Carlson and Winslow expires August 2004 [Page 5] INTERNET-DRAFT PPP Vendor Protocol February 2004 Type 3 Length >=7 Authentication-Protocol The hex value c05b, in Network Byte Order. OUI This three-octet field contains the vendors' Organizationally Unique Identifier. The bits within the octet are in canonical order, and the most significant octet is transmitted first. See Section 5 below for more information on OUI values. Data This optional field contains options or other information specific to the operation of the vendor-specific authentication protocol. 4.2. VSAP Authentication Data 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Code | Identifier | Length | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Data ... +-+-+-+-+ The Identifier and Length fields are as for LCP. The Code and Data fields and the processing of the messages are defined by the vendor- specific protocol. However, it is RECOMMENDED that vendor-specific protocols use Code 3 for "Success" and Code 4 for "Failure," as with  and , in order to simplify the design of network monitoring equipment. Carlson and Winslow expires August 2004 [Page 6] INTERNET-DRAFT PPP Vendor Protocol February 2004 5. Organizationally Unique Identifiers The three-octet Organizationally Unique Identifier (OUI) used in the messages described in this document identifies an organization ("ven- dor") that defines the meaning of the message. This OUI is based on IEEE 802 vendor assignments. Vendors that desire to use their IEEE 802 OUI for PPP Vendor Protocol SHOULD also register the assigned OUI with IANA for the benefit of the community. A vendor that does not otherwise need an IEEE-assigned OUI can request a PPP-specific OUI from the IANA. This OUI shall be assigned from the CF0000 series. This procedure is defined for vendors that are not able to use IEEE assignments, such as software-only vendors. 6. Multiple Vendor-Specific Protocols Vendors are encouraged to define their protocols to allow for future expansion, where necessary. For example, it may be appropriate for a VSNP to include a locally-defined selector field to distinguish among multiple proprietary protocols carried via this mechanism, and appropriate Configuration Options in VSNCP to enable and disable these sub-protocols. Because the requirements of such a selector are known only to the vendor defining such protocols, they are not described further in this document. An implementation MAY also support more than one vendor-specific pro- tocol, distinguished by OUI. In this case, the implementation MUST also treat LCP Protocol-Reject specially by examining the OUI field in the rejected message and disabling only the protocol to which it refers, rather than all use of the vendor-specific protocol number. Note that such an implementation is compatible with a simple imple- mentation that supports only one OUI: that implementation will respond with LCP Protocol-Reject for unrecognized OUIs and otherwise leave the negotiation state unmodified. An OUI-distinguished mechanism is expected to be used only in the case of cooperating vendors. Vendors are encouraged to use just a single OUI for all protocols defined by that vendor, if possible. 7. Multilink, Compression, and Encryption Considerations The Vendor-Specific Network Protocol (VSNP) is defined to operate at the bundle level if Multilink PPP  is in use, and also above any Compression Protocols  and Encryption Protocols  in use. Carlson and Winslow expires August 2004 [Page 7] INTERNET-DRAFT PPP Vendor Protocol February 2004 The Vendor-Specific Protocol (VSP) is defined to operate at the per- link level if Multilink PPP is in use, and MUST NOT be subjected to data compression. If a per-link encryption protocol is in use, then VSP packets MUST be encrypted. Note that because VSP is defined at the per-link level, bundle level encryption does not affect VSP. 8. Security Considerations The security of any vendor-specific authentication protocol is sub- ject to the provisions of that proprietary mechanism. Implementa- tions that wish to avoid security problems associated with such pro- tocols SHOULD send LCP Configure-Nak in response to an LCP Configure-Request specifying VSAP, or MAY terminate operation. When operating with PPP encryption but without Multilink PPP, VSP packets are sent in the clear. Implementations that require PPP encryption as part of a security mechanism should consider whether to employ per-link encryption or forego use of VSP in favor of VSNP. The security of vendor-specific networking protocols is likewise sub- ject to the security mechanisms defined by those protocols. Indepen- dent analysis of the security of any such protocol is RECOMMENDED. 9. IANA Considerations IANA has assigned four similarly-numbered PPP Protocol field values, 005b, 405b, 805b, and c05b, as described in Section 1 of this docu- ment. As described in Section 5 above and in , the IANA also maintains a CF0000 series block of non-IEEE OUIs that may be allocated for ven- dors that do not otherwise need an IEEE-assigned OUI. 10. Normative References  W. Simpson, Editor, "The Point-to-Point Protocol (PPP)," RFC 1661, July 1994  S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels," BCP 14 and RFC 2119, March 1997 Carlson and Winslow expires August 2004 [Page 8] INTERNET-DRAFT PPP Vendor Protocol February 2004 11. Informative References  W. Simpson, "PPP Vendor Extensions," RFC 2153, May 1997  W. Simpson, "PPP Challenge Handshake Authentication Protocol (CHAP)," RFC 1994, August 1996  L. Blunk, J. Vollbrecht, "PPP Extensible Authentication Protocol (EAP)," RFC 2284, March 1998  K. Sklower, B. Lloyd, G. McGregor, D. Carr, T. Coradetti, "The PPP Multilink Protocol (MP)," RFC 1990, August 1996  D. Rand, "The PPP Compression Control Protocol (CCP)," RFC 1962, June 1996  G. Meyer, "The PPP Encryption Control Protocol (ECP)," RFC 1968, June 1996. 12. Acknowledgments The authors thank Karl Fox and Thomas Narten for their comments and help in preparing this draft. Some of the language and phrasing has been borrowed from RFC 1332, written by Glenn McGregor, and 2153, written by William Allen Simp- son. 13. Authors Questions about this document should be addressed to the IETF pppext working group or the authors listed below. James Carlson Sun Microsystems 1 Network Drive MS UBUR02-212 Burlington MA 01803-2757 Email: <email@example.com> Phone: +1 781 442 2084 Fax: +1 781 442 1677 Richard Winslow L-3 Communications Systems - East 1 Federal Street A&E-2NE Camden, NJ 08102 EMail: firstname.lastname@example.org Carlson and Winslow expires August 2004 [Page 9] INTERNET-DRAFT PPP Vendor Protocol February 2004 14. Standard Notices 14.1. IETF Intellectual Property Statement "The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to per- tain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards- related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementers or users of this specification can be obtained from the IETF Secretariat. "The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights, which may cover technology that, may be required to practice this standard. Please address the information to the IETF Executive Director." 14.2. ISOC Copyright Statement "Copyright (C) The Internet Society 2004. All Rights Reserved. "This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of develop- ing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. "The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. "This document and the information contained herein is provided on an TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING Carlson and Winslow expires August 2004 [Page 10] INTERNET-DRAFT PPP Vendor Protocol February 2004 BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF MER- CHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE." 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