draft-ietf-rohc-ikev2-extensions-hcoipsec-05.txt   draft-ietf-rohc-ikev2-extensions-hcoipsec-06.txt 
Network Working Group J. Pezeshki Network Working Group J. Pezeshki
Internet-Draft E. Ertekin Internet-Draft E. Ertekin
Intended status: Experimental R. Jasani Expires: February 16, 2009 R. Jasani
Expires: July 3, 2008 C. Christou C. Christou
Booz Allen Hamilton Booz Allen Hamilton
December 31, 2007 August 15, 2008
IKEv2 Extensions to Support Robust Header Compression over IPsec IKEv2 Extensions to Support Robust Header Compression over IPsec
(RoHCoIPsec) (RoHCoIPsec)
draft-ietf-rohc-ikev2-extensions-hcoipsec-05 draft-ietf-rohc-ikev2-extensions-hcoipsec-06
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Copyright Notice
Copyright (C) The IETF Trust (2007).
Abstract Abstract
When using Robust Header Compression (RoHC [ROHC]) in conjunction In order to integrate RoHC with IPsec [ROHCOIPSEC], a mechanism is
with IPsec [IPSEC] (i.e. [RoHCOIPSEC]) a mechanism is needed to needed to negotiate RoHC configuration parameters between end-points.
negotiate RoHC configuration parameters between end-points prior to Internet Key Exchange (IKE) is a mechanism which can be leveraged to
operation. Internet Key Exchange (IKE) is a mechanism which can be handle these negotiations. This document specifies extensions to
leveraged to handle these negotiations. This document specifies IKEv2 [IKEV2] that will allow RoHC and its associated configuration
extensions to Internet Key Exchange (IKEv2 [IKEV2]) that will allow parameters to be negotiated for IPsec security associations (SAs).
RoHC and its associated configuration parameters to be negotiated for
IPsec security associations (SAs).
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
2. RoHC Channel Negotiation . . . . . . . . . . . . . . . . . . . 3 2. RoHC Channel Negotiation . . . . . . . . . . . . . . . . . . . 3
2.1. Negotiation of RoHC Channel Parameters . . . . . . . . . . 3 2.1. Negotiation of RoHC Channel Parameters . . . . . . . . . . 3
3. Security Considerations . . . . . . . . . . . . . . . . . . . . 6 3. Security Considerations . . . . . . . . . . . . . . . . . . . . 6
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 6
5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 7 5. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . 7
6. Normative References . . . . . . . . . . . . . . . . . . . . . 7 6. Normative References . . . . . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 8
Intellectual Property and Copyright Statements . . . . . . . . . . 9 Intellectual Property and Copyright Statements . . . . . . . . . . 9
1. Introduction 1. Introduction
Increased packet header overhead due to IPsec protection can result Increased packet header overhead due to IPsec [IPSEC] can result in
in inefficient utilization of bandwidth. Coupling RoHC with IPsec the inefficient utilization of bandwidth. Coupling RoHC [ROHC] with
offers an efficient way to transfer protected IP traffic. IPsec offers an efficient way to transfer protected IP traffic.
For proper RoHCoIPsec [ROHCOIPSEC] operation, RoHC requires The operation of RoHCoIPsec [ROHCOIPSEC] requires configuration
configuration parameters to be negotiated between the compressor and parameters to be negotiated between the compressor and decompressor.
decompressor, prior to operation. Current specifications of hop-by- Current specifications for hop-by-hop RoHC negotiate these parameters
hop RoHC schemes negotiate these parameters through a link-layer through a link-layer protocol such as Point-to-Point Protocol (PPP)
protocol such as Point-to-Point Protocol (PPP) (i.e. RoHC over PPP (i.e. RoHC over PPP [ROHCPPP]). Since key exchange protocols (e.g.
[ROHCPPP]). Similarly, key exchange protocols (e.g. IKEv2) are IKEv2) can be used to negotiate parameters between IPsec peers, this
commonly used to negotiate parameters between IPsec peers before a SA document defines extensions to IKEv2 to negotiate RoHC parameters for
can be established. This document proposes the use of IKEv2 to RoHCoIPsec.
handle RoHC channel configuration for RoHCoIPsec, and details various
extensions to IKEv2 which are intended to provide this functionality.
2. RoHC Channel Negotiation 2. RoHC Channel Negotiation
The initialization of a RoHC session requires the negotiation of a The initialization of a RoHC session requires the negotiation of a
set of configuration parameters (e.g. MAX_CID, etc.). As such, a set of configuration parameters (e.g. MAX_CID, etc.). The following
mechanism must exist for a RoHC enabled device to share a list of subsections define extensions to IKEv2 which enables an initiator to
supported RoHC parameters with its peer, and for the peer to select propose a set of RoHC parameters; the responder selects the
the appropriate parameters from this list. appropriate parameters from this list, and responds with the accepted
parameters for the RoHC channel.
Similarly, negotiable parameters must also be shared between IPsec
peers before a SA can be established. To perform this negotiation, a
key exchange protocol, IKEv2, is commonly used. IKEv2 is an
extensible protocol that negotiates parameters via request/response
message pairs (i.e. exchanges).
A set of extensions to IKEv2 can be defined, which will allow for
RoHC parameters to be negotiated during the creation and rekeying of
Child SAs. This new Notify payload will contain values for the set
of RoHC parameters to be negotiated between the two RoHC peers.
2.1. Negotiation of RoHC Channel Parameters 2.1. Negotiation of RoHC Channel Parameters
RoHC configuration parameters will be negotiated at either the RoHC configuration parameters will be negotiated at either the
establishment or rekeying of a Child SA. Specifically, a Notify establishment or rekeying of a Child SA. Specifically, a new Notify
payload will be used during the IKE_AUTH and CREATE_CHILD_SA payload is used during the IKE_AUTH and CREATE_CHILD_SA exchanges to
exchanges to negotiate the RoHCoIPsec session. The Notify payload negotiate these parameters.
sent by the initiator will contain the configuration parameters for
the RoHC scheme. Upon receipt of the initiator's request, the The Notify payload sent by the initiator contains the configuration
responder will either ignore the payload (if it doesn't support RoHC parameters for the RoHC implementation. Upon receipt of the
or the proposed parameters) or respond with a Notify payload that initiator's request, the responder will either ignore the payload (if
contains the accepted RoHC channel parameters. These accepted it doesn't support RoHC or the proposed parameters) or respond with a
parameters are subset of the parameters proposed by the initiator, Notify payload that contains the accepted RoHC channel parameters.
and the parameters supported by the responder (e.g. if the initiator The accepted parameters are an intersection between the parameters
proposes a MAX_CID value of 15, but the responder only supports a proposed by the initiator and the parameters supported by the
MAX_CID value of 13, the responder will respond with a value of 13, responder (e.g. if the initiator proposes a MAX_CID value of 15, but
which is supported by both parties). Note that only one Notify the responder only supports a MAX_CID value of 13, the responder will
payload is used to convey RoHC parameters per exchange. If multiple respond with a value of 13, which is supported by both parties).
Notify payloads relaying RoHC parameters are received by the
responder, all but the first such Notify payload must be dropped. Note that only one Notify payload is used to convey RoHC parameters
per exchange. If multiple Notify payloads relaying RoHC parameters
are received by the responder, all but the first such Notify payload
must be dropped. If the initiator does not receive a Notify Payload
with the responder's accepted RoHC channel parameters, RoHC must not
be enabled on the Child SA.
A new Notify Message Type value, denoted ROHC_SUPPORTED, will be A new Notify Message Type value, denoted ROHC_SUPPORTED, will be
added to indicate that the Notify payload is conveying RoHC channel added to indicate that the Notify payload is conveying RoHC channel
parameters. Additionally, several fields of the Notify payload (as parameters. Additionally, several fields of the Notify payload (as
defined in [IKEV2]) are set as follows: defined in [IKEV2]) are set as follows:
Critical (1 bit) Critical (1 bit)
This value is set to zero to indicate that the recipient must skip This value is set to zero to indicate that the recipient must skip
this payload if it does not understand the payload type code in this payload if it does not understand the payload type code in
the Next Payload field of the previous payload. the Next Payload field of the previous payload.
RESERVED (7 bits) RESERVED (7 bits)
Must be sent as zero, and must be ignored on receipt. Must be sent as zero, and must be ignored on receipt.
Protocol ID (1 octet) Protocol ID (1 octet)
Since the RoHC parameters are set at SA creation, and thus do not If the RoHC parameters are set at SA creation, this field must be
relate to an existing SA, this field must be set to zero. set to zero. If this notification concerns an existing SA, this
value may be set to (2) AH [AH], or (3) ESP [ESP].
SPI Size (1 octet) SPI Size (1 octet)
This value must be set to zero, since no SPI is applicable (RoHC This value must be set to zero, since no SPI is applicable (RoHC
parameters are set at SA creation, thus the SPI has not been parameters are set at SA creation, thus the SPI has not been
defined). defined).
Notify Message Type (2 octets) Notify Message Type (2 octets)
This field must be set to ROHC_SUPPORTED. This field must be set to ROHC_SUPPORTED.
RoHC configuration parameters will be communicated via a new Notify RoHC configuration parameters will be communicated via a new Notify
message type, denoted ROHC_SUPPORTED. The RoHC configuration message type, denoted ROHC_SUPPORTED. The RoHC configuration
parameters will be listed within the Notification Data field of the parameters will be listed within the Notification Data field of the
Notify payload, in the following format: Notify payload in the following format (default values for the
configuration parameters are consistent with [ROHCPPP]):
1 2 3 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 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
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! MAX_CID ! MRRU ! ! MAX_CID ! MRRU !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! MAX_HEADER ! PROFILE LENGTH ! ! MAX_HEADER ! PROFILE LENGTH !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! ! ! !
~ PROFILES... ~ ~ PROFILES... ~
! ! ! !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
! ! ! !
~ INTEGRITY ALGORITHMS... ~ ~ INTEGRITY ALGORITHMS... ~
! ! ! !
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: Notification Data field Figure 1. Notification Data field for the ROHC_SUPPORTED Notify
message type.
MAX_CID (2 octets) MAX_CID (2 octets)
The MAX_CID field indicates the maximum value of a context The MAX_CID field indicates the maximum value of a context
identifier. This value must be at least 0 and at most 16383 (The identifier. This value must be at least 0 and at most 16383 (The
value 0 implies having one context). value 0 implies having one context).
Suggested value: 15 Suggested value: 15
Note: The value of LARGE_CIDS will be implicitly determined by Note: The value of LARGE_CIDS will be implicitly determined by
this value (i.e. if MAX_CID is <= 15, LARGE_CIDS will be assumed this value (i.e. if MAX_CID is <= 15, LARGE_CIDS will be assumed
to be 0). to be 0).
MRRU (2 octets) MRRU (2 octets)
The MRRU field indicates the maximum reconstructed reception unit The MRRU field indicates the maximum reconstructed reception unit
(see [ROHC], section 5.1.1). (see [ROHC], section 5.1.1).
Suggested value: 0 Suggested value: 0
The MRRU value is used in conjunction with the segmentation The MRRU value is used in conjunction with the segmentation
protocol defined in RoHC. Since RoHCoIPsec will generally be protocol defined in RoHC. Since RoHC is implemented over an IPsec
implemented across multiple link-layer "hops", segmentation will SA, RoHC segmentation is not possible. Therefore, the MRRU value
not normally be required. In these cases the MRRU value will be must be set to zero, indicating that no segment headers are
set to zero, indicating that no segment headers are allowed on the allowed on the channel.
channel.
MAX_HEADER (2 octets) MAX_HEADER (2 octets)
The largest header size in octets that may be compressed. The largest header size in octets that may be compressed.
Suggested value: 168 octets Suggested value: 168 octets
Note: The MAX_HEADER parameter is not used for all RoHC profiles. Note: The MAX_HEADER parameter is not used for all RoHC profiles.
If none of the RoHC profiles require this field, this value is If none of the RoHC profiles require this field, this value is
ignored. ignored.
PROFILE LENGTH (2 octets) PROFILE LENGTH (2 octets)
skipping to change at page 6, line 20 skipping to change at page 6, line 20
(note that each RoHC profile is 2-octets in length). (note that each RoHC profile is 2-octets in length).
PROFILES PROFILES
The set of profiles to be enabled for the RoHC process. Profiles The set of profiles to be enabled for the RoHC process. Profiles
are further detailed in [ROHC]. In addition, several common are further detailed in [ROHC]. In addition, several common
profiles are defined in [ROHCPROF]. These 16-bit profile profiles are defined in [ROHCPROF]. These 16-bit profile
identifiers are to be sent in network byte order. identifiers are to be sent in network byte order.
INTEGRITY ALGORITHMS INTEGRITY ALGORITHMS
The set of Integrity Algorithms that may be use to ensure the The set of Integrity Algorithms that may be use to ensure the
integrity of the decompressed packets (i.e. ensure that the integrity of the decompressed packets (i.e. ensure that the packet
packets are properly decompressed). Each Integrity Algorithm is headers are properly decompressed). Each Integrity Algorithm is
represented by a 2-octet value that corresponds to the value represented by a 2-octet value that corresponds to the value
listed in [IKEV2-PARA] "For Transform Type 3 (Integrity listed in [IKEV2-PARA] "For Transform Type 3 (Integrity
Algorithm)" section. Algorithm)" section.
It is noted that:
1. The length of this field is inferred from the Notify Payload's
"Payload Length" field ([IKEV2], Section 3.10).
2. The key for this Integrity Algorithm is computed using the
same method as is used to compute IPsec's Integrity Algorithm
key ([IKEV2], Section 2.17).
Note: The length of this field is inferred from the Notify When a pair of SAs are created (one in each direction), the RoHC
Payload's "Payload Length" field ([IKEV2], Section 3.10). channel parameter FEEDBACK_FOR is set implicitly to the other SA of
the pair (i.e. the SA pointing in the reverse direction).
Note: The key for this Integrity Algorithm is computed using
the same method as is used to compute IPsec's Integrity
Algorithm key ([IKEV2], Section 2.17).
Note: When a pair of SAs are created (one in each direction), the
RoHC channel parameter FEEDBACK_FOR is set implicitly to the other SA
of the pair (i.e. the SA pointing in the reverse direction).
3. Security Considerations 3. Security Considerations
The RoHC parameters negotiated via IKEv2 do not add any new The RoHC parameters negotiated via IKEv2 do not add any new
vulnerabilities beyond those associated with the normal operation of vulnerabilities beyond those associated with the normal operation of
IKEv2. IKEv2.
4. IANA Considerations 4. IANA Considerations
This document defines a new Notify Message (Status Type). Therefore, This document defines a new Notify Message (Status Type). Therefore,
skipping to change at page 7, line 19 skipping to change at page 7, line 19
Espy of OPnet for their contributions and support in the development Espy of OPnet for their contributions and support in the development
of this document. The authors would also like to thank Mr. Tero of this document. The authors would also like to thank Mr. Tero
Kivinen for providing his technical expertise for this document. In Kivinen for providing his technical expertise for this document. In
addition, the authors would like to thank the following for their addition, the authors would like to thank the following for their
numerous reviews and comments to this document: numerous reviews and comments to this document:
o Dr. Stephen Kent o Dr. Stephen Kent
o Dr. Carsten Bormann o Dr. Carsten Bormann
o Mr. Lars-Erik Jonnson o Mr. Lars-Erik Jonnson
o Mr. Pasi Eronen o Mr. Pasi Eronen
o Dr. Joseph Touch
Finally, the authors would also like to thank Mr. Tom Conkle, Ms. Finally, the authors would also like to thank Mr. Tom Conkle, Ms.
Michele Casey, and Mr. Etzel Brower. Michele Casey, and Mr. Etzel Brower.
6. Normative References 6. Normative References
[ROHC] Bormann, C., Burmeister, C., Degermark, M., Fukushima, H., [ROHC] Bormann, C., Burmeister, C., Degermark, M., Fukushima, H.,
Hannu, H., Jonsson, L., Hakenberg, R., Koren, T., Le, K., Hannu, H., Jonsson, L., Hakenberg, R., Koren, T., Le, K.,
Liu, Z., Martensson, A., Miyazaki, A., Svanbro, K., Liu, Z., Martensson, A., Miyazaki, A., Svanbro, K.,
Wiebke, T., Yoshimura, T., and H. Zheng, "RObust Header Wiebke, T., Yoshimura, T., and H. Zheng, "RObust Header
Compression (ROHC): Framework and four profiles: RTP, UDP, Compression (ROHC): Framework and four profiles: RTP, UDP,
ESP, and uncompressed", RFC 3095, July 2001. ESP, and uncompressed", RFC 3095, July 2001.
[IPSEC] Kent, S. and K. Seo, "Security Architecture for the [IPSEC] Kent, S. and K. Seo, "Security Architecture for the
Internet Protocol", RFC 4301, December 2005. Internet Protocol", RFC 4301, December 2005.
[RoHCOIPSEC] [ROHCOIPSEC]
Ertekin, E., Christou, C., and R. Jasani, "Integration of Ertekin, E., Christou, C., and R. Jasani, "Integration of
Robust Header Compression over IPsec Security Robust Header Compression over IPsec Security
Associations", work in progress , June 2006. Associations", work in progress , June 2006.
[IKEV2] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol", [IKEV2] Kaufman, C., "Internet Key Exchange (IKEv2) Protocol",
RFC 4306, December 2005. RFC 4306, December 2005.
[ROHCPPP] Bormann, C., "Robust Header Compression (ROHC) over PPP", [ROHCPPP] Bormann, C., "Robust Header Compression (ROHC) over PPP",
RFC 3241, April 2002. RFC 3241, April 2002.
skipping to change at page 8, line 10 skipping to change at page 8, line 10
December 2005. December 2005.
[ESP] Kent, S., "IP Encapsulating Security Payload (ESP)", [ESP] Kent, S., "IP Encapsulating Security Payload (ESP)",
RFC 4303, December 2005. RFC 4303, December 2005.
[ROHCPROF] [ROHCPROF]
Pelletier, G. and K. Sandlund, "RObust Header Compression Pelletier, G. and K. Sandlund, "RObust Header Compression
Version 2 (RoHCv2): Profiles for RTP, UDP, IP, ESP and UDP Version 2 (RoHCv2): Profiles for RTP, UDP, IP, ESP and UDP
Lite", www.iana.org/assignments/ROHC-pro-ids , May 2007. Lite", www.iana.org/assignments/ROHC-pro-ids , May 2007.
[IKEV2PARA] [IKEV2-PARA]
"IKEv2 Parameters", IANA, "IKEv2 Parameters,
http://www.iana.org/assignments/ikev2-parameters , http://www.iana.org/assignments/ikev2-parameters",
November 2007. January 2008.
Authors' Addresses Authors' Addresses
Jonah Pezeshki Jonah Pezeshki
Booz Allen Hamilton Booz Allen Hamilton
13200 Woodland Park Dr. 13200 Woodland Park Dr.
Herndon, VA 20171 Herndon, VA 20171
US US
Email: pezeshki_jonah@bah.com Email: pezeshki_jonah@bah.com
skipping to change at page 9, line 7 skipping to change at page 9, line 7
Chris Christou Chris Christou
Booz Allen Hamilton Booz Allen Hamilton
13200 Woodland Park Dr. 13200 Woodland Park Dr.
Herndon, VA 20171 Herndon, VA 20171
US US
Email: christou_chris@bah.com Email: christou_chris@bah.com
Full Copyright Statement Full Copyright Statement
Copyright (C) The IETF Trust (2007). Copyright (C) The IETF Trust (2008).
This document is subject to the rights, licenses and restrictions This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors contained in BCP 78, and except as set forth therein, the authors
retain all their rights. retain all their rights.
This document and the information contained herein are provided on an This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
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