draft-ietf-stir-rph-emergency-services-01.txt   draft-ietf-stir-rph-emergency-services-02.txt 
STIR M. Dolly STIR M. Dolly
Internet-Draft AT&T Internet-Draft AT&T
Intended status: Standards Track C. Wendt Intended status: Standards Track C. Wendt
Expires: September 10, 2020 Comcast Expires: January 14, 2021 Comcast
March 09, 2020 July 13, 2020
Assertion Values for a Resource Priority Header Claim in Support of Assertion Values for a Resource Priority Header Claim and a SIP Priority
Emergency Services Networks Header Claim in Support of Emergency Services Networks
draft-ietf-stir-rph-emergency-services-01 draft-ietf-stir-rph-emergency-services-02
Abstract Abstract
This document adds new assertion values for a Resource Priority This document adds new assertion values for a Resource Priority
Header ("rph") claim defined in RFC 8443, in support of Emergency Header ("rph") claim and a new SIP Priority Header claim ("sph") for
Services Networks for emergency call origination and callback. protection of the "psap-callback" value as part of the "rph" PASSporT
extension, in support of the security of Emergency Services Networks
for emergency call origination and callback.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79. provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/. Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
This Internet-Draft will expire on September 10, 2020. This Internet-Draft will expire on January 14, 2021.
Copyright Notice Copyright Notice
Copyright (c) 2020 IETF Trust and the persons identified as the Copyright (c) 2020 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of (https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. New Assertion Values . . . . . . . . . . . . . . . . . . . . 3 3. New Assertion Values for "rph" claim . . . . . . . . . . . . 3
3.1. ESorig . . . . . . . . . . . . . . . . . . . . . . . . . 3 3.1. ESorig . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.2. EScallback . . . . . . . . . . . . . . . . . . . . . . . 3 3.2. EScallback . . . . . . . . . . . . . . . . . . . . . . . 4
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4 4. The SIP Priority header "sph" claim . . . . . . . . . . . . . 4
4.1. PASSporT Resource Priority Header (rph) Types . . . . . . 4 5. Order of Claim Keys . . . . . . . . . . . . . . . . . . . . . 5
5. Security Considerations . . . . . . . . . . . . . . . . . . . 5 6. Compact Form of PASSporT . . . . . . . . . . . . . . . . . . 5
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 5
6.1. Normative References . . . . . . . . . . . . . . . . . . 5 7.1. PASSporT Resource Priority Header (rph) Types . . . . . . 5
6.2. Informative References . . . . . . . . . . . . . . . . . 6 7.2. JSON Web Token claims . . . . . . . . . . . . . . . . . . 6
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 6 8. Security Considerations . . . . . . . . . . . . . . . . . . . 6
9. References . . . . . . . . . . . . . . . . . . . . . . . . . 6
9.1. Normative References . . . . . . . . . . . . . . . . . . 6
9.2. Informative References . . . . . . . . . . . . . . . . . 7
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 8
1. Introduction 1. Introduction
Personal Assertion Token (PASSporT) Extension for Resource Priority Personal Assertion Token (PASSporT) Extension for Resource Priority
Authorization [RFC8443] extended the Personal Assertion Token Authorization [RFC8443] extended the Personal Assertion Token
(PASSporT) specification defined in [RFC8225] to allow the inclusion (PASSporT) specification defined in [RFC8225] to allow the inclusion
of cryptographically signed assertions of authorization for the of cryptographically signed assertions of authorization for the
values populated in the Session Initiation Protocol (SIP) 'Resource- values populated in the Session Initiation Protocol (SIP) "Resource-
Priority' header field, which is used for communications resource Priority" header field [RFC4412], which is used for communications
prioritization. resource prioritization and the SIP "Priority" header field, used for
categorizing the priority use of the call.
Compromise of the SIP 'Resource-Priority' header field [RFC4412] Compromise of the SIP "Resource-Priority" header field could lead to
could lead to misuse of network resources (i.e., during congestion misuse of network resources (i.e., during congestion scenarios),
scenarios), impacting the application services supported using the impacting the application services supported using the SIP "Resource-
SIP 'Resource-Priority' header field. Priority" header field.
[RFC8225] allows extensions by which an authority on the originating [RFC8225] allows extensions by which an authority on the originating
side verifying the authorization of a particular communication for side verifying the authorization of a particular communication for
the SIP 'Resource-Priority' header field can use a PASSPorT claim to the SIP "Resource-Priority" header field or the SIP "Priority" header
cryptographically sign the SIP 'Resource-Priority' header field and field can use PASSPorT claims to cryptographically sign the
convey assertion of the authorization for the SIP 'Resource-Priority' information associated with either the SIP "Resource-Priority" or
header field. A signed SIP 'Resource-Priority' header field will "Priority" header fields and convey assertion of those values by the
allow a receiving entity (including entities located in different signing party authorization. A signed SIP "Resource-Priority" or
network domains/boundaries) to verify the validity of assertions "Priority" header fields will allow a receiving entity (including
authorizing the SIP 'Resource-Priority' header field and to act on entities located in different network domains/boundaries) to verify
the information with confidence that the information has not been the validity of assertions to act on the information with confidence
spoofed or compromised. that the information has not been spoofed or compromised.
This document adds new assertion values for a Resource Priority This document adds new assertion values for a Resource Priority
Header ("rph") claim defined in [RFC8443], in support of Emergency Header ("rph") claim defined in [RFC8443], in support of Emergency
Services Networks for emergency call origination and callback. How Services Networks for emergency call origination and callback. This
these new assertion values for real-time communications supported document also defines a new claim, "sph", including protection of the
using the SIP 'Resource-Priority' header field is outside the scope SIP Priority header for the indication of an emergency service call-
of this document. In addition, the PASSPorT extension defined in back assigned the value "psap-callback" as defined in [RFC7090]. The
this document is intended for use in environments where there are use of these new assertion values for real-time communications
means to verify that the signer of the SIP 'Resource-Priority' header supported using the SIP 'Resource-Priority' and 'Priority' header
field is authoritative. fields for emergency services is introduced in
[I-D.rosen-stir-emergency-calls] but otherwise out-of-scope of this
document. In addition, the PASSPorT claims and values defined in
this document are intended for use in environments where there are
means to verify that the signer of the SIP 'Resource-Priority' and
'Priority' header fields is authoritative.
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP "OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here. capitals, as shown here.
3. New Assertion Values 3. New Assertion Values for "rph" claim
This specification defines new assertions values for: This specification defines new assertions values for:
* "ESorig": Emergency Services call origination * "ESorig": Emergency Services call origination
* "EScallback": Emergency Services callback. * "EScallback": Emergency Services callback.
3.1. ESorig 3.1. ESorig
When using "ESorig" as the "rph" assertion value, the "orig" claim of When using "ESorig" as the "rph" assertion value, the "orig" claim of
the PASSporT MUST represent the calling party number that initiates the PASSporT MUST represent the calling party number that initiates
skipping to change at page 3, line 38 skipping to change at page 4, line 7
country or region specific dial string (e.g., "911" for North America country or region specific dial string (e.g., "911" for North America
or "112" GSM defined string used in Europe and other countries) or or "112" GSM defined string used in Europe and other countries) or
"urn:service:sos" as defined in TBD, representing the emergency "urn:service:sos" as defined in TBD, representing the emergency
services destination of the call. services destination of the call.
The following is an example of an "rph" claim for SIP 'Resource- The following is an example of an "rph" claim for SIP 'Resource-
Priority' header field with a "ESorig" assertion: Priority' header field with a "ESorig" assertion:
{ {
"orig":{"tn":"12155551212"}, "orig":{"tn":"12155551212"},
"dest":{["tn":"urn:service:sos"]}, "dest":{["uri":"urn:service:sos"]},
"iat":1443208345, "iat":1443208345,
"rph":{"ESorig":["esnet,x"]} "rph":{"ESorig":["esnet,x"]}
} }
3.2. EScallback 3.2. EScallback
When using "EScallback" as the "rph" assertion value, the "orig" When using "EScallback" as the "rph" assertion value, the "orig"
claim of the PASSporT MUST represent the emergency network telephone claim of the PASSporT MUST represent the emergency network telephone
number. The "dest" claim MUST be the telephone number representing number. The "dest" claim MUST be the telephone number representing
the original calling party of the emergency service call that is the original calling party of the emergency service call that is
skipping to change at page 4, line 26 skipping to change at page 4, line 41
their signature is generated normally per the guidance in [RFC8225] their signature is generated normally per the guidance in [RFC8225]
using the full form of PASSPorT. The credentials (i.e., Certificate) using the full form of PASSPorT. The credentials (i.e., Certificate)
used to create the signature must have authority over the namespace used to create the signature must have authority over the namespace
of the "rph" claim, and there is only one authority per claim. The of the "rph" claim, and there is only one authority per claim. The
authority MUST use its credentials associated with the specific authority MUST use its credentials associated with the specific
service supported by the resource priority namespace in the claim. service supported by the resource priority namespace in the claim.
If r-values are added or dropped by the intermediaries along the If r-values are added or dropped by the intermediaries along the
path, the intermediaries must generate a new "rph" header and sign path, the intermediaries must generate a new "rph" header and sign
the claim with their own authority. the claim with their own authority.
4. The SIP Priority header "sph" claim
As discussed in [I-D.rosen-stir-emergency-calls], and as defined in
[RFC7090] the SIP Priority header may be set to the value "psap-
callback" for emergency services callback calls. Because some SIP
networks may act on this value and provide priority or other special
routing based on this value, it is important to protect and validate
the authoritative use associated with it.
Therefore, we define a new claim key as part of the "rph" PASSporT,
"sph", which MUST be used only for authorized emergency callbacks and
correspond to a SIP Priority header with the value "psap-callback".
The value of the "sph" claim key should only be "psap-callback" to
match the SIP Priority header field value for authorized emergency
services callbacks.
The following is an example of an "sph" claim for SIP 'Priority'
header field with the value "psap-callback":
{
"orig":{"tn":"12155551213"},
"dest":{["tn":"12155551212"]},
"iat":1443208345,
"rph":{"EScallback":["esnet,x"]},
"sph":"psap-callback"
}
5. Order of Claim Keys
The order of the claim keys MUST follow the rules of [RFC8225]
Section 9; the claim keys MUST appear in lexicographic order.
Therefore, the claim keys discussed in this document appear in the
PASSporT Payload in the following order,
o dest
o iat
o orig
o rph
o sph
6. Compact Form of PASSporT
The use of the compact form of PASSporT is not specified in this The use of the compact form of PASSporT is not specified in this
document. document or recommended for 'rph' PASSporTs.
4. IANA Considerations 7. IANA Considerations
4.1. PASSporT Resource Priority Header (rph) Types 7.1. PASSporT Resource Priority Header (rph) Types
This specification requests that the IANA add two new assertion This specification requests that the IANA add two new assertion
values to the "PASSporT Resource Priority Header (rph) Types" values to the "PASSporT Resource Priority Header (rph) Types"
Registry as defined in [RFC8443]. Registry as defined in [RFC8443].
The following assertion values will be added to the registry: The following assertion values will be added to the registry:
* "ESorig": Emergency Services call origination * "ESorig": Emergency Services call origination
* "EScallback": Emergency Services callback * "EScallback": Emergency Services callback
+--------------+------------+ +--------------+------------+
| rph Type | Reference | | rph Type | Reference |
+--------------+------------+ +--------------+------------+
| ESorig | [this RFC] | | ESorig | [this RFC] |
+--------------+------------+ +--------------+------------+
| EScallback | [this RFC] | | EScallback | [this RFC] |
+--------------+------------+ +--------------+------------+
5. Security Considerations 7.2. JSON Web Token claims
This specification requests that the IANA add two new claims to the
JSON Web Token Claims registry as defined in [RFC7519].
Claim Name: "sph"
Claim Description: SIP Priority header field
Change Controller: IESG
Specification Document(s): [RFCThis]
8. Security Considerations
The security considerations discussed in [RFC8224], Section 12, are The security considerations discussed in [RFC8224], Section 12, are
applicable here. applicable here.
6. References 9. References
6.1. Normative References 9.1. Normative References
[I-D.rosen-stir-emergency-calls]
Rosen, B., "Non-Interactive Emergency Calls", draft-rosen-
stir-emergency-calls-00 (work in progress), March 2020.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E. A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", RFC 3261, Schooler, "SIP: Session Initiation Protocol", RFC 3261,
DOI 10.17487/RFC3261, June 2002, DOI 10.17487/RFC3261, June 2002,
<https://www.rfc-editor.org/info/rfc3261>. <https://www.rfc-editor.org/info/rfc3261>.
[RFC4412] Schulzrinne, H. and J. Polk, "Communications Resource [RFC4412] Schulzrinne, H. and J. Polk, "Communications Resource
Priority for the Session Initiation Protocol (SIP)", Priority for the Session Initiation Protocol (SIP)",
RFC 4412, DOI 10.17487/RFC4412, February 2006, RFC 4412, DOI 10.17487/RFC4412, February 2006,
<https://www.rfc-editor.org/info/rfc4412>. <https://www.rfc-editor.org/info/rfc4412>.
[RFC7090] Schulzrinne, H., Tschofenig, H., Holmberg, C., and M.
Patel, "Public Safety Answering Point (PSAP) Callback",
RFC 7090, DOI 10.17487/RFC7090, April 2014,
<https://www.rfc-editor.org/info/rfc7090>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token [RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015, (JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://www.rfc-editor.org/info/rfc7519>. <https://www.rfc-editor.org/info/rfc7519>.
[RFC8224] Peterson, J., Jennings, C., Rescorla, E., and C. Wendt, [RFC8224] Peterson, J., Jennings, C., Rescorla, E., and C. Wendt,
"Authenticated Identity Management in the Session "Authenticated Identity Management in the Session
Initiation Protocol (SIP)", RFC 8224, Initiation Protocol (SIP)", RFC 8224,
DOI 10.17487/RFC8224, February 2018, DOI 10.17487/RFC8224, February 2018,
<https://www.rfc-editor.org/info/rfc8224>. <https://www.rfc-editor.org/info/rfc8224>.
skipping to change at page 6, line 5 skipping to change at page 7, line 34
[RFC8226] Peterson, J. and S. Turner, "Secure Telephone Identity [RFC8226] Peterson, J. and S. Turner, "Secure Telephone Identity
Credentials: Certificates", RFC 8226, Credentials: Certificates", RFC 8226,
DOI 10.17487/RFC8226, February 2018, DOI 10.17487/RFC8226, February 2018,
<https://www.rfc-editor.org/info/rfc8226>. <https://www.rfc-editor.org/info/rfc8226>.
[RFC8443] Singh, R., Dolly, M., Das, S., and A. Nguyen, "Personal [RFC8443] Singh, R., Dolly, M., Das, S., and A. Nguyen, "Personal
Assertion Token (PASSporT) Extension for Resource Priority Assertion Token (PASSporT) Extension for Resource Priority
Authorization", RFC 8443, DOI 10.17487/RFC8443, August Authorization", RFC 8443, DOI 10.17487/RFC8443, August
2018, <https://www.rfc-editor.org/info/rfc8443>. 2018, <https://www.rfc-editor.org/info/rfc8443>.
6.2. Informative References 9.2. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997, DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[RFC7340] Peterson, J., Schulzrinne, H., and H. Tschofenig, "Secure [RFC7340] Peterson, J., Schulzrinne, H., and H. Tschofenig, "Secure
Telephone Identity Problem Statement and Requirements", Telephone Identity Problem Statement and Requirements",
RFC 7340, DOI 10.17487/RFC7340, September 2014, RFC 7340, DOI 10.17487/RFC7340, September 2014,
<https://www.rfc-editor.org/info/rfc7340>. <https://www.rfc-editor.org/info/rfc7340>.
 End of changes. 21 change blocks. 
49 lines changed or deleted 130 lines changed or added

This html diff was produced by rfcdiff 1.47. The latest version is available from http://tools.ietf.org/tools/rfcdiff/