draft-ietf-stir-rph-06.txt   rfc8443.txt 
STIR R. Singh Internet Engineering Task Force (IETF) R. Singh
Internet-Draft Vencore Labs Request for Comments: 8443 Vencore Labs
Intended status: Standards Track M. Dolly Category: Standards Track M. Dolly
Expires: November 25, 2018 AT&T ISSN: 2070-1721 AT&T
S. Das S. Das
Vencore Labs Vencore Labs
A. Nguyen A. Nguyen
Office of Emergency Communication/DHS Office of Emergency Communications/DHS
May 24, 2018 August 2018
PASSporT Extension for Resource Priority Authorization Personal Assertion Token (PASSporT) Extension
draft-ietf-stir-rph-06 for Resource Priority Authorization
Abstract Abstract
This document extends the PASSporT (Personal Assertion Token) This document extends the Personal Assertion Token (PASSporT)
specification defined in [RFC8225] to allow the inclusion of specification defined in RFC 8225 to allow the inclusion of
cryptographically signed assertions of authorization for the values cryptographically signed assertions of authorization for the values
populated in the 'Session Initiation Protocol (SIP) Resource- populated in the Session Initiation Protocol (SIP) 'Resource-
Priority' header field, which is used for communications resource Priority' header field, which is used for communications resource
prioritization. prioritization.
Status of This Memo Status of This Memo
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provisions of BCP 78 and BCP 79.
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Internet Standards is available in Section 2 of RFC 7841.
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and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8443.
Copyright Notice Copyright Notice
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Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. PASSporT 'rph' Claim . . . . . . . . . . . . . . . . . . . . 3 3. PASSporT "rph" Claim . . . . . . . . . . . . . . . . . . . . 4
4. 'rph' in SIP . . . . . . . . . . . . . . . . . . . . . . . . 5 4. "rph" in SIP . . . . . . . . . . . . . . . . . . . . . . . . 5
4.1. Authentication Service Behavior . . . . . . . . . . . . . 5 4.1. Authentication Service Behavior . . . . . . . . . . . . . 5
4.2. Verification Service Behavior . . . . . . . . . . . . . . 5 4.2. Verification Service Behavior . . . . . . . . . . . . . . 6
5. Further Information Associated with 'Resource-Priority' . . . 6 5. Further Information Associated with the SIP
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 'Resource-Priority' Header Field . . . . . . . . . . . . . . 7
6.1. JSON Web Token Claims . . . . . . . . . . . . . . . . . . 6 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
6.1. JSON Web Token Claims . . . . . . . . . . . . . . . . . . 7
6.2. PASSporT Types . . . . . . . . . . . . . . . . . . . . . 7 6.2. PASSporT Types . . . . . . . . . . . . . . . . . . . . . 7
7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 7. Security Considerations . . . . . . . . . . . . . . . . . . . 8
7.1. Avoidance of replay and cut and paste attacks . . . . . . 7 7.1. Avoidance of Replay and Cut-and-Paste Attacks . . . . . . 8
7.2. Solution Considerations . . . . . . . . . . . . . . . . . 7 7.2. Solution Considerations . . . . . . . . . . . . . . . . . 8
7.3. Acknowledgements . . . . . . . . . . . . . . . . . . . . 8
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 8
8.1. Normative References . . . . . . . . . . . . . . . . . . 8 8.1. Normative References . . . . . . . . . . . . . . . . . . 8
8.2. Informative References . . . . . . . . . . . . . . . . . 9 8.2. Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 9 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 10
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10
1. Introduction 1. Introduction
PASSporT [RFC8225] is a token format based on JSON Web Token (JWT) PASSporT [RFC8225] is a token format based on JSON Web Token (JWT)
[RFC7519] for conveying cryptographically signed information about [RFC7519] for conveying cryptographically signed information about
the identities involved in personal communications. PASSporT with the identities involved in personal communications. PASSporT with
STIR [RFC8224] provides a mechanism by which an authority on the Secure Telephone Identity Revisited (STIR) [RFC8224] provides a
originating side of a call via a protocol like SIP [RFC3261] can mechanism by which an authority on the originating side of a call,
provide a cryptographic assurance of the validity of the calling using a protocol like SIP [RFC3261], can provide a cryptographic
party telephone number in order to prevent impersonation attacks. assurance of the validity of the calling party telephone number in
order to prevent impersonation attacks.
[RFC4412] defines the 'SIP Resource-Priority' header field for [RFC4412] defines a mechanism to prioritize access to SIP-signaled
communications 'Resource-Priority'. As specified in [RFC4412], the resources during periods of communications resource scarcity using
'SIP Resource-Priority' header field may be used by SIP user agents the SIP 'Resource-Priority' header. As specified in [RFC4412], the
[RFC3261] (including Public Switched Telephone Network (PSTN) SIP 'Resource-Priority' header field may be used by SIP user agents
(UAs) [RFC3261] (including Public Switched Telephone Network (PSTN)
gateways and SIP proxy servers) to influence prioritization afforded gateways and SIP proxy servers) to influence prioritization afforded
to communication sessions including PSTN calls (e.g., to manage to communication sessions, including PSTN calls (e.g., to manage
scarce network resources during network congestion scenarios). scarce network resources during network congestion scenarios).
However, the 'SIP Resource-Priority' header field could be spoofed However, the SIP 'Resource-Priority' header field could be spoofed
and abused by unauthorized entities, the threat models and use cases and abused by unauthorized entities, the threat models and use cases
of which are described in [RFC7375] and [RFC7340], respectively. of which are described in [RFC7375] and [RFC7340], respectively.
Compromise of the 'SIP Resource-Priority' header field [RFC4412] Compromise of the SIP 'Resource-Priority' header field [RFC4412]
could lead to misuse of network resource (i.e., during congestion could lead to misuse of network resources (i.e., during congestion
scenarios) resulting in impacts to the application services supported scenarios), impacting the application services supported using the
using the 'SIP Resource-Priority' header field. SIP 'Resource-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
'SIP Resource-Priority' can use a PASSPorT claim to cryptographically the SIP 'Resource-Priority' header field can use a PASSPorT claim to
sign the 'SIP Resource-Priority' header field and convey assertion of cryptographically sign the SIP 'Resource-Priority' header field and
the authorization for 'Resource-Priority'. Signed 'SIP Resource- convey assertion of the authorization for the SIP 'Resource-Priority'
Priority' header field will allow a receiving entity (including header field. A signed SIP 'Resource-Priority' header field will
entities located in different network domains/boundaries) to verify allow a receiving entity (including entities located in different
the validity of assertions authorizing 'Resource-Priority' and to act network domains/boundaries) to verify the validity of assertions
on the information with confidence that the information has not been authorizing the SIP 'Resource-Priority' header field and to act on
the information with confidence that the information has not been
spoofed or compromised. spoofed or compromised.
This specification documents an extension to PASSporT and the This specification documents an extension to PASSporT and the
associated STIR mechanisms to provide a function to cryptographically associated STIR mechanisms to provide a function to cryptographically
sign the 'SIP Resource-Priority' header field. This PASSporT object sign the SIP 'Resource-Priority' header field. This PASSporT object
is used to provide attestation of a calling user authorization for is used to provide attestation of a calling-user authorization for
priority communications. This is necessary in addition to the priority communications. This is necessary in addition to the
PASSporT object that is used for calling user telephone number PASSporT object that is used for calling-user telephone-number
attestation. How this extension to PASSporT is used for real-time attestation. How this extension to PASSporT is used for real-time
communications supported using 'SIP Resource-Priority' header field communications supported using the SIP 'Resource-Priority' header
is outside the scope of this document. In addition, the PASSPorT field is outside the scope of this document. In addition, the
extension defined in this document is intended for use in PASSPorT extension defined in this document is intended for use in
environments where there are means to verify that the signer of the environments where there are means to verify that the signer of the
'SIP Resource-Priority' header field is authoritative. SIP 'Resource-Priority' header field 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", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
document are to be interpreted as described in RFC 2119 [RFC2119] and "OPTIONAL" in this document are to be interpreted as described in
in RFC 8174 [RFC8174]. BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. PASSporT 'rph' Claim 3. PASSporT "rph" Claim
This specification defines a new JSON Web Token claim for "rph", This specification defines a new JSON Web Token claim for "rph" that
which provides an assertion for information in 'SIP Resource- provides an assertion for information in the SIP 'Resource-Priority'
Priority' header field. header field.
The creator of a PASSporT object adds a "ppt" value of "rph" to the The creator of a PASSporT object adds a "ppt" value of "rph" to the
header of a PASSporT object, in which case the PASSporT claims MUST header of a PASSporT object. The PASSporT claims MUST contain an
contain a "rph" claim, and any entities verifying the PASSporT object "rph" claim, and any entities verifying the PASSporT object will be
will be required to understand the "ppt" extension in order to required to understand the "ppt" extension in order to process the
process the PASSporT in question. A PASSPorT header with the "ppt" PASSporT in question. A PASSPorT header with the "ppt" included will
included will look as follows: look as follows:
{ {
"typ":"passport", "typ":"passport",
"ppt":"rph", "ppt":"rph",
"alg":"ES256", "alg":"ES256",
"x5u":"https://www.example.org/cert.cer" "x5u":"https://www.example.org/cert.cer"
} }
The "rph" claim will provide an assertion of authorization, "auth", The "rph" claim will provide an assertion of authorization, "auth",
for information in the 'SIP Resource-Priority' header field based on for information in the SIP 'Resource-Priority' header field based on
[RFC4412] and the syntax is: [RFC4412]. The syntax is:
{ {
Resource-Priority = "Resource-Priority" : r-value, Resource-Priority = "Resource-Priority" : r-value,
r-value= namespace "." r-priority r-value = namespace "." r-priority
} }
Specifically, the "rph" claim includes an assertion of the priority- Specifically, the "rph" claim includes an assertion of the priority
level of the user to be used for a given communication session. The level of the user to be used for a given communication session. The
value of the "rph" claim is an Object with one or more keys. Each value of the "rph" claim is an object with one or more keys. Each
key is associated with a JSON Array. These arrays contain Strings key is associated with a JSON array. These arrays contain strings
that correspond to the r-values indicated in the 'SIP Resource- that correspond to the r-values indicated in the SIP 'Resource-
Priority' header field. Priority' header field.
The following is an example "rph" claim for a 'SIP Resource-Priority' The following is an example "rph" claim for a SIP 'Resource-Priority'
header field with one r-value of "ets.0" and with another r-value of header field with one r-value of "ets.0" and with another r-value of
"wps.0": "wps.0":
{ {
"orig":{"tn":"12155550112"}, "orig":{"tn":"12155550112"},
"dest":{["tn":"12125550113"]}, "dest":{["tn":"12125550113"]},
"iat":1443208345, "iat":1443208345,
"rph":{"auth":["ets.0", "wps.0"]} "rph":{"auth":["ets.0", "wps.0"]}
} }
After the header and claims PASSporT objects have been constructed, After the header and claims PASSporT objects have been constructed,
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, intermediaries must generate a new "rph" header and sign the path, the intermediaries must generate a new "rph" header and sign
claim with its own authority. the claim with their own authority.
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.
4. 'rph' in SIP 4. "rph" in SIP
This section specifies SIP-specific usage for the "rph" claim in This section specifies SIP-specific usage for the "rph" claim in
PASSporT. PASSporT.
4.1. Authentication Service Behavior 4.1. Authentication Service Behavior
The Authentication Service will create the "rph" claim using the The Authentication Service will create the "rph" claim using the
values discussed in section 3 of this document that are based on values discussed in Section 3 of this document that are based on
[RFC4412]. The construction of "rph" claim follows the steps [RFC4412]. The construction of the "rph" claim follows the steps
described in Section 4.1 of [RFC8224]. described in Section 4.1 of [RFC8224].
The resulting Identity header for "rph" might look as The resulting Identity header for "rph" might look as follows
follows(backslashes shown for line folding only): (backslashes shown for line folding only):
Identity:eyJhbGciOiJFUzI1NiIsInBwdCI6InJwaCIsInR5cCI6InBhc3Nwb3J0\ Identity:eyJhbGciOiJFUzI1NiIsInBwdCI6InJwaCIsInR5cCI6InBhc3Nwb3J0\
IiwieDV1IjoiaHR0cHM6Ly93d3cuZXhhbXBsZS5jb20vY2VydC5jZXIifQo.eyJkZ\ IiwieDV1IjoiaHR0cHM6Ly93d3cuZXhhbXBsZS5jb20vY2VydC5jZXIifQo.eyJkZ\
XN0Ijp7WyJ0biI6IjEyMTI1NTUwMTEzIl19LCJpYXQiOiIxNDQzMjA4MzQ1Iiwib3\ XN0Ijp7WyJ0biI6IjEyMTI1NTUwMTEzIl19LCJpYXQiOiIxNDQzMjA4MzQ1Iiwib3\
JpZyI6eyJ0biI6IjEyMTU1NTUwMTEyIn0sInJwaCI6eyJhdXRoIjpbImV0cy4wIiw\ JpZyI6eyJ0biI6IjEyMTU1NTUwMTEyIn0sInJwaCI6eyJhdXRoIjpbImV0cy4wIiw\
id3BzLjAiXX19Cg.s37S6VC8HM6Dl6YzJeQDsrZcwJ0lizxhUrA7f_98oWBHvo-cl\ id3BzLjAiXX19Cg.s37S6VC8HM6Dl6YzJeQDsrZcwJ0lizxhUrA7f_98oWBHvo-cl\
-n8MIhoCr18vYYFy3blXvs3fslM_oos2P2Dyw;info=<https://www.example.\ -n8MIhoCr18vYYFy3blXvs3fslM_oos2P2Dyw;info=<https://www.example.\
org/cert.cer>;alg=ES256;ppt="rph" org/cert.cer>;alg=ES256;ppt="rph"
A SIP authentication service will derive the value of "rph" from the A SIP authentication service will derive the value of "rph" from the
'SIP Resource-Priority' header field based on policy associated with SIP 'Resource-Priority' header field based on policy associated with
service specific use of the "namespace "." r-priority" for r-values service-specific use of r-values, defined as follows in [RFC4412]:
based on [RFC4412]. The authentication service derives the value of
the PASSPorT claim by verifying the authorization for 'SIP Resource- r-value = namespace "." r-priority
Priority' (i.e., verifying a calling user privilege for 'Resource-
Priority' based on its identity) which might be derived from customer The authentication service derives the value of the PASSPorT claim by
profile data or from access to external services. verifying the authorization for the SIP 'Resource-Priority' header
field (i.e., verifying a calling-user privilege for the SIP
'Resource-Priority' header field based on its identity). The
authorization might be derived from customer-profile data or access
to external services.
[RFC4412] allows multiple "namespace "." priority value" pairs, [RFC4412] allows multiple "namespace "." priority value" pairs,
either in a single 'SIP Resource-Priority' header field or across either in a single SIP 'Resource-Priority' header field or across
multiple 'SIP Resource-Priority' headers. An authority is multiple SIP 'Resource-Priority' header fields. An authority is
responsible for signing all the content of a 'SIP Resource-Priority' responsible for signing all the content of a SIP 'Resource-Priority'
header field for which it has the authority. header field for which it has the authority.
4.2. Verification Service Behavior 4.2. Verification Service Behavior
[RFC8224] Section 6.2 Step 5 requires that specifications defining [RFC8224], Section 6.2, Step 5 requires that specifications defining
"ppt" values describe any additional verifier behavior. The behavior "ppt" values describe any additional verifier behavior. The behavior
specified for the "ppt" values of "rph" is as follows: specified for the "ppt" values of "rph" is as follows:
The verification service MUST extract the value associated with the The verification service MUST extract the value associated with the
"auth" key in a full form PASSPorT with a "ppt" value of "rph". If "auth" key in a full-form PASSPorT with a "ppt" value of "rph". If
the signature validates, then the verification service can use the the signature validates, then the verification service can use the
value of the "rph" claim as validation that the calling party is value of the "rph" claim as validation that the calling party is
authorized for 'SIP Resource-Priority' as indicated in the claim. authorized for SIP 'Resource-Priority' header fields as indicated in
This value would in turn be used for priority treatment in accordance the claim. This value would, in turn, be used for priority treatment
with local policy for the associated communication service. If the in accordance with local policy for the associated communication
signature validation fails, the verification service should infer service. If the signature validation fails, the verification service
that the calling party is not authorized for 'SIP Resource-Priority' should infer that the calling party is not authorized for SIP
as indicated in the claim. In such cases, the priority treatment for 'Resource-Priority' header fields as indicated in the claim. In such
the associated communication service is handled as per the local cases, the priority treatment for the associated communication
policy of the verifier. In such scenarios, 'SIP Resource-Priority' service is handled as per the local policy of the verifier. In such
header field SHOULD be stripped from SIP request and the network scenarios, the SIP 'Resource-Priority' header field SHOULD be
entities should treat the call as an ordinary call. stripped from the SIP request, and the network entities should treat
the call as an ordinary call.
In addition, [RFC8224] Section 6.2 Step 4 requires the "iat" value in In addition, [RFC8224], Section 6.2, Step 4 requires the "iat" value
"rph" claim to be verified. in "rph" claim to be verified.
The behavior of a SIP UA upon receiving an INVITE containing a The behavior of a SIP UA upon receiving an INVITE containing a
PASSporT object with a "rph" claim will largely remain a matter of PASSporT object with an "rph" claim will largely remain a matter of
implementation policy for the specific communication service. In implementation policy for the specific communication service. In
most cases, implementations would act based on confidence in the most cases, implementations would act based on confidence in the
veracity of this information. veracity of this information.
5. Further Information Associated with 'Resource-Priority' 5. Further Information Associated with the SIP 'Resource-Priority'
Header Field
There may be additional information about the calling party or the There may be additional information about the calling party or the
call that could be relevant to authorization for 'SIP Resource- call that could be relevant to authorization for the SIP 'Resource-
Priority'. This may include information related to the device Priority' header field. This may include information related to the
subscription of the caller, or to any institutions that the caller or device subscription of the caller, to any institutions that the
device is associated with, or even categories of institutions. All caller or device is associated with, or even to categories of
of these data elements would benefit from the secure attestations institutions. All of these data elements would benefit from the
provided by the STIR and PASSporT frameworks. The specification of secure attestations provided by the STIR and PASSporT frameworks.
the "rph" claim could entail the optional presence of one or more The specification of the "rph" claim could entail the optional
such additional information fields applicable to 'SIP Resource- presence of one or more such additional information fields applicable
Priority'. to the SIP 'Resource-Priority' header field.
A new IANA registry has been defined to hold potential values of the A new IANA registry has been defined to hold potential values of the
"rph" array; see Section 6.2. The definition of the "rph" claim may "rph" array; see Section 6.2. The definition of the "rph" claim may
have one or more such additional information field(s). Details of have one or more such additional information field(s). Details of
such "rph" claim to encompass other data elements are left for future how an "rph" claim encompasses other data elements are left for
version of this specification. future specifications.
6. IANA Considerations 6. IANA Considerations
6.1. JSON Web Token Claims 6.1. JSON Web Token Claims
This specification requests that the IANA add a new claim to the JSON IANA has added a new claim to the "JSON Web Token Claims" registry as
Web Token Claims registry as defined in [RFC7519]. defined in [RFC7519].
o Claim Name: "rph" o Claim Name: "rph"
o Claim Description: Resource Priority Header Authorization o Claim Description: Resource Priority Header Authorization
o Change Controller: IESG o Change Controller: IESG
o Specification Document(s): Section 3 of [RFCThis] o Specification Document(s): Section 3 of RFC 8443
6.2. PASSporT Types 6.2. PASSporT Types
This specification also requests that the IANA creates a new entry to IANA has created a new entry in the "Personal Assertion Token
the PASSporT Types registry for the type "rph" which is specified in (PASSporT) Extensions" registry for the type "rph", which is
[RFCThis]. In addition, another registry needs to be created in specified in this document. In addition, the "PASSporT Resource
which each entry must contain two fields: the name of the "rph" type Priority Header (rph) Types" registry has been created in which each
and the specification in which the type is described. This registry entry must contain two fields: the name of the "rph" type and the
is to be initially populated with a single value for "auth" which is specification in which the type is described. This registry has been
specified in [RFCThis]. Registration of new "rph" types shall be initially populated with the single value for "auth", which is
under the specification required policy. specified in this document. Registration of new "rph" types shall be
under the Specification Required policy[RFC8126].
7. Security Considerations 7. Security Considerations
The security considerations discussed in [RFC8224] in Section 12 are The security considerations discussed in [RFC8224], Section 12, are
applicable here. applicable here.
7.1. Avoidance of replay and cut and paste attacks 7.1. Avoidance of Replay and Cut-and-Paste Attacks
The PASSporT extension with a "ppt" value of "rph" MUST only be sent The PASSporT extension with a "ppt" value of "rph" MUST only be sent
with SIP INVITE when 'Resource-Priority' header field is used to with SIP INVITE when the SIP 'Resource-Priority' header field is used
convey the priority of the communication as defined in [RFC4412]. To to convey the priority of the communication, as defined in [RFC4412].
avoid replay, and cut and paste attacks, the recommendations provided To avoid replay and cut-and-paste attacks, the recommendations
in Section 12.1 of [RFC8224] MUST be followed. provided in Section 12.1 of [RFC8224] MUST be followed.
7.2. Solution Considerations 7.2. Solution Considerations
Using extensions to PASSporT tokens with a "ppt" value of "rph" Using extensions to PASSporT tokens with a "ppt" value of "rph"
requires knowledge of the authentication, authorization, and requires knowledge of the authentication, authorization, and
reputation of the signer to attest to the identity being asserted, reputation of the signer to attest to the identity being asserted,
including validating the digital signature and the associated including validating the digital signature and the associated
certificate chain to a trust anchor. The following considerations certificate chain to a trust anchor. The following considerations
should be recognized when using PASSporT extensions with a "ppt" should be recognized when using PASSporT extensions with a "ppt"
value of "rph": value of "rph":
o A signer is only allowed to sign the content of a 'SIP Resource- o A signer is only allowed to sign the content of a SIP 'Resource-
Priority' header field for which it has the proper authorization. Priority' header field for which it has the proper authorization.
Before signing tokens, the signer MUST have a secure method for Before signing tokens, the signer MUST have a secure method for
authentication of the end user or the device being granted a authentication of the end user or the device being granted a
token. token.
o The verification of the signature MUST include means of verifying o The verification of the signature MUST include means of verifying
that the signer is authoritative for the signed content of the that the signer is authoritative for the signed content of the
resource priority namespace in the PASSporT. resource priority namespace in the PASSporT.
7.3. Acknowledgements
We would like to thank STIR WG members, ATIS/SIP Forum Task Force on
IPNNI members, and the NS/EP Priority Services community for
contributions to this problem statement and specification. We would
also like to thank David Hancock and Ning Zhang for their valuable
inputs.
8. References 8. References
8.1. Normative References 8.1. Normative 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,
<http://www.rfc-editor.org/info/rfc2119>. <https://www.rfc-editor.org/info/rfc2119>.
[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,
<http://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,
<http://www.rfc-editor.org/info/rfc4412>. <https://www.rfc-editor.org/info/rfc4412>.
[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,
<http://www.rfc-editor.org/info/rfc7519>. <https://www.rfc-editor.org/info/rfc7519>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <http://www.rfc-editor.org/info/rfc8174>. May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[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,
<http://www.rfc-editor.org/info/rfc8224>. <https://www.rfc-editor.org/info/rfc8224>.
[RFC8225] Wendt, C. and J. Peterson, "PASSporT:Personal Assertion [RFC8225] Wendt, C. and J. Peterson, "PASSporT: Personal Assertion
Token", RFC 8225, DOI 10.17487/RFC8225, February 2018, Token", RFC 8225, DOI 10.17487/RFC8225, February 2018,
<http://www.rfc-editor.org/info/rfc8225>. <https://www.rfc-editor.org/info/rfc8225>.
8.2. Informative References 8.2. Informative References
[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,
<http://www.rfc-editor.org/info/rfc7340>. <https://www.rfc-editor.org/info/rfc7340>.
[RFC7375] Peterson, J., "Secure Telephone Identity Threat Model", [RFC7375] Peterson, J., "Secure Telephone Identity Threat Model",
RFC 7375, DOI 10.17487/RFC7375, October 2014, RFC 7375, DOI 10.17487/RFC7375, October 2014,
<http://www.rfc-editor.org/info/rfc7375>. <https://www.rfc-editor.org/info/rfc7375>.
[RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for
Writing an IANA Considerations Section in RFCs", BCP 26,
RFC 8126, DOI 10.17487/RFC8126, June 2017,
<https://www.rfc-editor.org/info/rfc8126>.
Acknowledgements
We would like to thank STIR Working Group members, the ATIS/SIP Forum
Task Force on IPNNI members, and the NS/EP Priority Services
community for contributions to this problem statement and
specification. We would also like to thank David Hancock and Ning
Zhang for their valuable inputs.
Authors' Addresses Authors' Addresses
Ray P. Singh Ray P. Singh
Vencore Labs Vencore Labs
150 Mount Airy Road 150 Mount Airy Road
New Jersey, NJ 07920 New Jersey, NJ 07920
USA United States of America
Email: rsingh@vencorelabs.com Email: rsingh@vencorelabs.com
Martin Dolly Martin Dolly
AT&T AT&T
200 Laurel Avenue 200 Laurel Avenue
Middletown, NJ 07748 Middletown, NJ 07748
USA United States of America
Email: md3135@att.com Email: md3135@att.com
Subir Das Subir Das
Vencore Labs Vencore Labs
150 Mount Airy Road 150 Mount Airy Road
New Jersey, NJ 07920 New Jersey, NJ 07920
USA United States of America
Email: sdas@vencorelabs.com Email: sdas@vencorelabs.com
An Nguyen An Nguyen
Office of Emergency Communication/DHS Office of Emergency Communications
Department of Homeland Security
245 Murray Lane, Building 410 245 Murray Lane, Building 410
Washington, DC 20528 Washington, DC 20528
USA United States of America
Email: an.p.nguyen@HQ.DHS.GOV Email: an.p.nguyen@HQ.DHS.GOV
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