draft-ietf-stir-passport-11.txt   rfc8225.txt 
STIR C. Wendt Internet Engineering Task Force (IETF) C. Wendt
Internet-Draft Comcast Request for Comments: 8225 Comcast
Intended status: Standards Track J. Peterson Category: Standards Track J. Peterson
Expires: August 13, 2017 Neustar Inc. ISSN: 2070-1721 Neustar Inc.
February 09, 2017 February 2018
Personal Assertion Token (PASSporT) PASSporT: Personal Assertion Token
draft-ietf-stir-passport-11
Abstract Abstract
This document defines a method for creating and validating a token This document defines a method for creating and validating a token
that cryptographically verifies an originating identity, or more that cryptographically verifies an originating identity or, more
generally a URI or telephone number representing the originator of generally, a URI or telephone number representing the originator of
personal communications. The PASSporT token is cryptographically personal communications. The Personal Assertion Token, PASSporT, is
signed to protect the integrity of the identity the originator and to cryptographically signed to protect the integrity of the identity of
verify the assertion of the identity information at the destination. the originator and to verify the assertion of the identity
The cryptographic signature is defined with the intention that it can information at the destination. The cryptographic signature is
confidently verify the originating persona even when the signature is defined with the intention that it can confidently verify the
sent to the destination party over an insecure channel. PASSporT is originating persona even when the signature is sent to the
particularly useful for many personal communications applications destination party over an insecure channel. PASSporT is particularly
over IP networks and other multi-hop interconnection scenarios where useful for many personal-communications applications over IP networks
the originating and destination parties may not have a direct trusted and other multi-hop interconnection scenarios where the originating
relationship. and destination parties may not have a direct trusted relationship.
Status of This Memo Status of This Memo
This Internet-Draft is submitted in full conformance with the This is an Internet Standards Track document.
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
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Internet-Drafts are draft documents valid for a maximum of six months This document is a product of the Internet Engineering Task Force
and may be updated, replaced, or obsoleted by other documents at any (IETF). It represents the consensus of the IETF community. It has
time. It is inappropriate to use Internet-Drafts as reference received public review and has been approved for publication by the
material or to cite them other than as "work in progress." Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
This Internet-Draft will expire on August 13, 2017. Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8225.
Copyright Notice Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the Copyright (c) 2018 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction ....................................................4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology .....................................................4
3. PASSporT Token Overview . . . . . . . . . . . . . . . . . . . 4 3. PASSporT Overview ...............................................5
4. PASSporT Header . . . . . . . . . . . . . . . . . . . . . . . 5 4. PASSporT Header .................................................6
4.1. "typ" (Type) Header Parameter . . . . . . . . . . . . . . 5 4.1. "typ" (Type) Header Parameter ..............................6
4.2. "alg" (Algorithm) Header Parameter . . . . . . . . . . . 5 4.2. "alg" (Algorithm) Header Parameter .........................6
4.3. "x5u" (X.509 URL) Header Parameter . . . . . . . . . . . 5 4.3. "x5u" (X.509 URL) Header Parameter .........................6
4.4. Example PASSporT header . . . . . . . . . . . . . . . . . 6 4.4. Example PASSporT Header ....................................7
5. PASSporT Payload . . . . . . . . . . . . . . . . . . . . . . 6 5. PASSporT Payload ................................................7
5.1. JWT defined claims . . . . . . . . . . . . . . . . . . . 6 5.1. JWT-Defined Claims .........................................7
5.1.1. "iat" - Issued At claim . . . . . . . . . . . . . . . 6 5.1.1. "iat" (Issued At) Claim .............................7
5.2. PASSporT specific claims . . . . . . . . . . . . . . . . 6 5.2. PASSporT-Specific Claims ...................................8
5.2.1. Originating and Destination Identity Claims . . . . . 7 5.2.1. Originating and Destination Identity Claims .........8
5.2.2. "mky" - Media Key claim . . . . . . . . . . . . . . . 8 5.2.2. "mky" (Media Key) Claim ............................10
6. PASSporT Signature . . . . . . . . . . . . . . . . . . . . . 10 6. PASSporT Signature .............................................11
7. Compact form of PASSporT . . . . . . . . . . . . . . . . . . 10 7. Compact Form of PASSporT .......................................12
7.1. Example Compact form PASSporT Token . . . . . . . . . . . 11 7.1. Example Compact Form of PASSporT ..........................13
8. Extending PASSporT . . . . . . . . . . . . . . . . . . . . . 11 8. Extending PASSporT .............................................13
8.1. "ppt" (PASSporT) header parameter . . . . . . . . . . . . 12 8.1. "ppt" (PASSporT) Header Parameter .........................13
8.2. Example extended PASSporT header . . . . . . . . . . . . 12 8.2. Example Extended PASSporT Header ..........................14
8.3. Extended PASSporT Claims . . . . . . . . . . . . . . . . 13 8.3. Extended PASSporT Claims ..................................14
9. Deterministic JSON Serialization . . . . . . . . . . . . . . 13 9. Deterministic JSON Serialization ...............................15
9.1. Example PASSport deterministic JSON form . . . . . . . . 14 9.1. Example PASSporT Deterministic JSON Form ..................16
10. Security Considerations . . . . . . . . . . . . . . . . . . . 15 10. Security Considerations .......................................17
10.1. Avoidance of replay and cut and paste attacks . . . . . 15 10.1. Avoidance of Replay and Cut-and-Paste Attacks ............17
10.2. Solution Considerations . . . . . . . . . . . . . . . . 15 10.2. Solution Considerations ..................................18
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16 11. IANA Considerations ...........................................18
11.1. Media Type Registration . . . . . . . . . . . . . . . . 16 11.1. Media Type Registration ..................................18
11.1.1. Media Type Registry Contents Additions Requested . . 16 11.2. Registrations in "JSON Web Token Claims" .................19
11.2. JSON Web Token Claims Registration . . . . . . . . . . . 17 11.3. Registration in "JSON Web Signature and
11.2.1. Registry Contents Additions Requested . . . . . . . 17 Encryption Header Parameters" ............................20
11.3. JSON Web Signature and Encryption Header Parameter 11.4. PASSporT Extensions Registry .............................20
Registry . . . . . . . . . . . . . . . . . . . . . . . . 18 12. References ....................................................20
11.3.1. Registry Contents Additions Requested . . . . . . . 18 12.1. Normative References .....................................20
11.4. PASSporT Extension Registry Request . . . . . . . . . . 18 12.2. Informative References ...................................22
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 18 Appendix A. Example ES256-Based PASSporT JWS Serialization and
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 Signature .............................................23
13.1. Normative References . . . . . . . . . . . . . . . . . . 18 A.1. X.509 Private Key in PKCS #8 Format for ES256 Example ......24
13.2. Informative References . . . . . . . . . . . . . . . . . 20 A.2. X.509 Public Key for ES256 Example .........................25
Appendix A. Example ES256 based PASSporT JWS Serialization and Acknowledgments ...................................................25
Signature . . . . . . . . . . . . . . . . . . . . . 20 Authors' Addresses ................................................25
A.1. X.509 Private Key in PKCS#8 format for ES256 Example** . 22
A.2. X.509 Public Key for ES256 Example** . . . . . . . . . . 22
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
1. Introduction 1. Introduction
In today's IP-enabled telecommunications world, there is a growing In today's IP-enabled telecommunications world, there is a growing
concern about the ability to trust incoming invitations for concern about the ability to trust incoming invitations for
communications sessions, including video, voice and messaging communications sessions, including video, voice, and messaging
[RFC7340]. As an example, modern telephone networks provide the [RFC7340]. As an example, modern telephone networks provide the
ability to spoof the calling party telephone number for many ability to spoof the calling party's telephone number for many
legitimate purposes including providing network features and services legitimate purposes, including providing network features and
on the behalf of a legitimate telephone number. However, as we have services on behalf of a legitimate telephone number. However, as we
seen, bad actors have taken advantage of this ability for have seen, bad actors have taken advantage of this ability for
illegitimate and fraudulent purposes meant to trick telephone users illegitimate and fraudulent purposes meant to trick telephone users
to believe they are someone they are not. This problem can be into believing that they are someone they are not. This problem can
extended to many emerging forms of personal communications. be extended to many emerging forms of personal communications.
This document defines a method for creating and validating a token This document defines a method for creating and validating a token
that cryptographically verifies an originating identity, or more that cryptographically verifies an originating identity or, more
generally a URI or telephone number representing the originator of generally, a URI or telephone number representing the originator of
personal communications. Through extensions defined in this personal communications. Through the extensions defined in Section 8
document, in Section 8, other information relevant to the personal of this document, other information relevant to the personal
communications can also be added to the token. The goal of PASSporT communications can also be added to the token. The goal of PASSporT
is to provide a common framework for signing originating identity is to provide a common framework for signing information related to
related information in an extensible way. Additionally, this the originating identity in an extensible way. Additionally, this
functionality is independent of any specific personal communications functionality is independent of any specific call logic for
signaling call logic, so that the assertion of originating identity personal-communications signaling, so that the assertion of
related information can be implemented in a flexible way and can be information related to the originating identity can be implemented in
used in applications including end-to-end applications that require a flexible way and can be used in such applications as end-to-end
different signaling protocols or gateways between different applications that require different signaling protocols or gateways
communications systems. It is anticipated that signaling protocol between different communications systems. It is anticipated that
specific guidance will be provided in other related documents and guidance specific to the signaling protocol will be provided in other
specifications to specify how to use and transport PASSporT tokens, related documents and specifications to specify how to use and
however this is intentionally out of scope for this document. transport PASSporTs; however, this is intentionally out of scope for
this document.
[I-D.ietf-stir-rfc4474bis] provides details of the use of PASSporT [RFC8224] provides details of the use of PASSporT within the SIP
within SIP [RFC3261] signaling protocol for the signing and [RFC3261] signaling protocol for the signing and verification of
verification of telephone numbers and SIP URIs. telephone numbers and SIP URIs.
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]. "OPTIONAL" in this document are to be interpreted as described in
BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
3. PASSporT Token Overview 3. PASSporT Overview
JSON Web Token (JWT) [RFC7519] and JSON Web Signature (JWS) [RFC7515] "JSON Web Token (JWT)" [RFC7519], "JSON Web Signature (JWS)"
and related specifications define a standard token format that can be [RFC7515], and other related specifications define a standard token
used as a way of encapsulating claimed or asserted information with format that can be used as a way of encapsulating claimed or asserted
an associated digital signature using X.509 based certificates. JWT information with an associated digital signature using X.509-based
provides a set of claims in JSON format that can conveniently certificates. JWT provides a set of claims in JSON format that can
accommodate asserted originating identity information and is easily conveniently accommodate asserted originating-identity information
extensible for extension mechanisms defined below. Additionally, JWS and that are easily extensible for use in the extension mechanisms
provides a path for updating methods and cryptographic algorithms defined below. Additionally, JWS provides a path for updating
used for the associated digital signatures. methods and cryptographic algorithms used for the associated digital
signatures.
JWS defines the use of JSON data structures in a specified canonical JWS defines the use of JSON data structures in a specified canonical
format for signing data corresponding to JOSE header, JWS Payload, format for signing data corresponding to the JSON Object Signing and
and JWS Signature. JWT defines a set of claims that are represented Encryption (JOSE) Header, JWS Payload, and JWS Signature. JWT
by specified JSON objects which can be extended with custom keys for defines a set of claims that are represented by specified JSON
specific applications. The next sections define the header and objects that can be extended with custom keys for specific
claims that MUST be minimally used with JWT and JWS for PASSporT. applications. The next sections define the header and claims that
MUST be minimally used with JWT and JWS for PASSporT.
PASSporT specifically uses this token format and defines claims that PASSporT specifically uses this token format and defines claims that
convey the identity of the origination and destination of personal convey the identity of the origination and destination of personal
communications. The originating identity, the primary value asserted communications. The primary value asserted in a PASSporT object is
in a PASSporT object represents the identity of the calling party or the originating identity representing the identity of the calling
the initiator of a personal communications session. The signer of a party or the initiator of a personal-communications session. The
PASSporT object may or may not correspond to the origination signer of a PASSporT object may or may not correspond to the
identity. For a given application's use or using protocol of originating identity. For a given application's use or using
PASSporT the creation of the PASSporT object is performed by an protocol of PASSporT, the creation of the PASSporT object is
entity that is authoritative to assert the callers identity. This performed by an entity that is authoritative to assert the caller's
authority is represented by the certificate credentials and the identity. This authority is represented by the certificate
signature and PASSporT object is created and initiated to the credentials and the signature, and the PASSporT object is created and
destination(s) at the applications choice of authoritative point(s) initiated to the destination(s) per the application's choice of
in the network. For example, the PASSporT object could be created at authoritative point(s) in the network. For example, the PASSporT
a device that has authenticated with a user, or at a network entity object could be created at a device that has authenticated with a
with an authenticated trust relationship with that device and it's user or at a network entity with an authenticated trust relationship
user. Destination identities represent the intended destination of with that device and its user. Destination identities represent the
the personal communications, i.e. the identity(s) being called by the intended destination of the personal communications, i.e., the
caller. The destination point(s) determined by the application need identity(s) being called by the caller. The destination point or
to have the capability to verify the PASSporT token and the digital points determined by the application need to have the capability to
signature. The PASSporT associated certificate is used to validate verify the PASSporT and the digital signature. The PASSporT-
the authority of the originating signer, generally via a certificate associated certificate is used to validate the authority of the
chain to the trust anchor for that application. originating signer, generally via a certificate chain to the trust
anchor for that application.
4. PASSporT Header 4. PASSporT Header
The JWS token header is a JOSE header, [RFC7515] Section 4, that The JWS token header is a JOSE Header ([RFC7515], Section 4) that
defines the type and encryption algorithm used in the token. defines the type and encryption algorithm used in the token.
PASSporT header should include, at a minimum, the header parameters The PASSporT header should include, at a minimum, the Header
defined in the next three subsections. Parameters defined in the next three subsections.
4.1. "typ" (Type) Header Parameter 4.1. "typ" (Type) Header Parameter
The "typ" (Type) Header Parameter is defined in JWS [RFC7515] The "typ" (Type) Header Parameter is defined in JWS ([RFC7515],
Section 4.1.9. to declare the media type of the complete JWS. Section 4.1.9) to declare the media type of the complete JWS.
For PASSporT Token the "typ" header MUST be the string "passport". For the PASSporT, the "typ" header MUST be the string "passport".
This represents that the encoded token is a JWT of type passport. This signifies that the encoded token is a JWT of type "passport".
4.2. "alg" (Algorithm) Header Parameter 4.2. "alg" (Algorithm) Header Parameter
The "alg" (Algorithm) Header Parameter is defined in JWS [RFC7515] The "alg" (Algorithm) Header Parameter is defined in JWS ([RFC7515],
Section 4.1.1. This definition includes the ability to specify the Section 4.1.1). This definition includes the ability to specify the
use of a cryptographic algorithm for the signature part of the JWS. use of a cryptographic algorithm for the signature part of the JWS.
It also refers to a list of defined "alg" values as part of a It also refers to a list of defined "alg" values as part of a
registry established by JSON Web Algorithms (JWA) [RFC7518] registry established by JSON Web Algorithms (JWA) ([RFC7518],
Section 3.1. Section 3.1).
For the creation and verification of PASSporT tokens and their For the creation and verification of PASSporTs and their digital
digital signatures, implementations MUST support ES256 as defined in signatures, implementations MUST support ES256 as defined in JWA
JWA [RFC7518] Section 3.4. Implementations MAY support other ([RFC7518], Section 3.4). Implementations MAY support other
algorithms registered in the JSON Web Signature and Encryption algorithms registered in the "JSON Web Signature and Encryption
Algorithms registry created by [RFC7518]. The contents of that Algorithms" registry created by [RFC7518]. The contents of that
registry may be updated in the future depending on cryptographic registry may be updated in the future, depending on cryptographic
strength requirements guided by current security best practice. The strength requirements guided by current security best practices. The
mandatory-to-support algorithm for PASSporT tokens may likewise be mandatory-to-support algorithm for PASSporTs may likewise be updated
updated in future updates to this document. in future updates to this document.
Implementations of PASSporT digital signatures using ES256 as defined Implementations of PASSporT digital signatures using ES256 as defined
above SHOULD use deterministic ECDSA if/when supported for the above SHOULD use the deterministic Elliptic Curve Digital Signature
reasons stated in [RFC6979]. Algorithm (ECDSA) if or when supported for the reasons stated in
[RFC6979].
4.3. "x5u" (X.509 URL) Header Parameter 4.3. "x5u" (X.509 URL) Header Parameter
As defined in JWS [RFC7515] Section 4.1.5., the "x5u" header As defined in JWS ([RFC7515], Section 4.1.5), the "x5u" Header
parameter defines a URI [RFC3986] referring to the resource for the Parameter defines a URI [RFC3986] referring to the resource for the
X.509 public key certificate or certificate chain [RFC5280] X.509 public key certificate or certificate chain [RFC5280]
corresponding to the key used to digitally sign the JWS. Generally, corresponding to the key used to digitally sign the JWS. Generally,
as defined in JWS [RFC7515] section 4.1.5, this would correspond to as defined in JWS ([RFC7515], Section 4.1.5), this would correspond
an HTTPS or DNSSEC resource using integrity protection. to an HTTPS or DNSSEC resource using integrity protection.
4.4. Example PASSporT header 4.4. Example PASSporT Header
An example of the header, would be the following, including the An example of the header would be the following, including the
specified passport type, ES256 algorithm, and a URI referencing the specified passport type, ES256 algorithm, and a URI referencing the
network location of the certificate needed to validate the PASSporT network location of the certificate needed to validate the PASSporT
signature. signature.
{ {
"typ":"passport", "typ":"passport",
"alg":"ES256", "alg":"ES256",
"x5u":"https://cert.example.org/passport.cer" "x5u":"https://cert.example.org/passport.cer"
} }
5. PASSporT Payload 5. PASSporT Payload
The token claims consist of the information which needs to be The token claims consist of the information that needs to be verified
verified at the destination party. These claims follow the at the destination party. These claims follow the definition of a
definition of a JWT claim [RFC7519] Section 4 and are encoded as JWT claim ([RFC7519], Section 4) and are encoded as defined by the
defined by the JWS Payload [RFC7515] Section 3. JWS Payload ([RFC7515], Section 3).
PASSporT defines the use of a standard JWT defined claim as well as PASSporT defines the use of a standard JWT-defined claim as well as
custom claims corresponding to the two parties associated with custom claims corresponding to the two parties associated with
personal communications, the originator and destination as detailed personal communications -- the originator and destination, as
below. detailed below.
Any claim names MUST use the US-ASCII character set. Any claim For PASSporT, any claim names MUST use the ASCII character set. Any
values can container characters that are outside the US-ASCII range, claim values can contain characters that are outside the ASCII range,
however MUST follow the default JSON serialization defined in consistent with the rules of creating a JWT Claims Set as defined in
[RFC7519] Section 7. [RFC7519], Section 7.1.
5.1. JWT defined claims 5.1. JWT-Defined Claims
5.1.1. "iat" - Issued At claim 5.1.1. "iat" (Issued At) Claim
The JSON claim MUST include the "iat" [RFC7519] Section 4.1.6 defined The JSON claim MUST include the "iat" (Issued At) claim ([RFC7519],
claim Issued At. As defined the "iat" should be set to the date and Section 4.1.6). As defined, the "iat" claim should be set to the
time of issuance of the JWT and MUST the origination of the personal date and time of issuance of the JWT and MUST indicate the date and
communications. The time value should be of the format defined in time of the origination of the personal communications. The time
[RFC7519] Section 2 NumericDate. This is included for securing the value should be of the NumericDate format as defined in [RFC7519],
token against replay and cut and paste attacks, as explained further Section 2. This is included for securing the token against replay
in the security considerations in Section 10. and cut-and-paste attacks, as explained further in Section 10
("Security Considerations").
5.2. PASSporT-Specific Claims
5.2. PASSporT specific claims
5.2.1. Originating and Destination Identity Claims 5.2.1. Originating and Destination Identity Claims
The origination and destination identities are represented by two The originating identity and the destination identity are represented
claims that are required for PASSporT, the "orig" and "dest" claims. by two claims that are required for PASSporT -- the "orig" and "dest"
Both "orig" and "dest" MUST contain claim values that are identity claims. Both "orig" and "dest" MUST contain claim values that are
claim JSON objects where the child claim name represents an identity identity claim JSON objects where the child claim name represents an
type and the claim value is the identity string, both defined in identity type and the claim value is the identity string, both
subsequent subsections. Currently, these identities can be defined in subsequent subsections. Currently, these identities can
represented as either telephone numbers or Uniform Resource be represented as either telephone numbers or Uniform Resource
Indicators (URIs). Indicators (URIs).
The "orig" claim is a JSON object with the claim name of "orig" and a The "orig" claim is a JSON object with the claim name of "orig" and a
claim value which is a JSON object representing the asserted identity claim value that is a JSON object representing the asserted identity
of any type (currently either "tn" or "uri") of the originator of the of any type (currently either "tn" or "uri") of the originator of the
personal communications signaling. There MUST be exactly one "orig" personal-communications signaling. There MUST be exactly one "orig"
claim with exactly one identity claim object in a PASSporT object. claim with exactly one identity claim object in a PASSporT object.
Note, as explained in Section 3, the originating identity represents Note: As explained in Section 3, the originating identity represents
the calling party and may or may not correspond to the authoritative the calling party and may or may not correspond to the authoritative
signer of the token. signer of the token.
The "dest" is a JSON object with the claim name of "dest" and MUST The "dest" claim is a JSON object with the claim name of "dest" and
have at least have one identity claim object. The "dest" claim value MUST have at least one identity claim object. The "dest" claim value
is an array containing one or more identity claim JSON objects is an array containing one or more identity claim JSON objects
representing the destination identities of any type (currently "tn" representing the destination identities of any type (currently "tn"
or "uri"). If the "dest" claim value array contains both "tn" and or "uri"). If the "dest" claim value array contains both "tn" and
"uri" claim names, the JSON object should list the "tn" array first "uri" claim names, the JSON object should list the "tn" array first
and the "uri" array second. Within the "tn" and "uri" arrays, the and the "uri" array second. Within the "tn" and "uri" arrays, the
identity strings should be put in lexicographical order including the identity strings should be put in lexicographical order, including
scheme-specific portion of the URI characters. the scheme-specific portion of the URI characters.
Note, as explained in Section 3, the destination identity represents Note: As explained in Section 3, the destination identity represents
the called party and may or may not correspond to the authoritative the called party and may or may not correspond to the authoritative
party verifying the token signature. party verifying the token signature.
5.2.1.1. "tn" - Telephone Number identity 5.2.1.1. "tn" (Telephone Number) Identity
If the originating or destination identity is a telephone number, the If the originating or destination identity is a telephone number, the
claim name representing the identity MUST be "tn". claim name representing the identity MUST be "tn".
The claim value for the "tn" claim is the telephone number and MUST The claim value for the "tn" claim is the telephone number and MUST
be canonicalized according to the procedures specified in be canonicalized according to the procedures specified in [RFC8224],
[I-D.ietf-stir-rfc4474bis] Section 8.3. Section 8.3.
5.2.1.2. "uri" - URI identity 5.2.1.2. "uri" (URI) Identity
If any of the originating or destination identities is of the form If any of the originating or destination identities is in the form of
URI, as defined in [RFC3986], the claim name representing the a URI as defined in [RFC3986], the claim name representing the
identity MUST be "uri" and the claim value is the URI form of the identity MUST be "uri", and the claim value is the URI form of the
identity. identity.
5.2.1.3. Future identity forms 5.2.1.3. Future Identity Forms
We recognize that in the future there may be other standard We recognize that in the future there may be other standard
mechanisms for representing identities. The "orig" and "dest" claims mechanisms for representing identities. The "orig" and "dest" claims
currently support "tn" and "uri" but could be extended in the future currently support "tn" and "uri" but could be extended in the future
to allow for other identity types with new IANA registered unique to allow for other identity types with new IANA-registered unique
types to represent these forms. types to represent these forms.
5.2.1.4. Examples 5.2.1.4. Examples
Single originator, with telephone number identity +12155551212, to The following is an example of a single originator with telephone
single destination, with URI identity 'sip:alice@example.com', number identity +12155551212, to a single destination with URI
example: identity "sip:alice@example.com":
{ {
"dest":{"uri":["sip:alice@example.com"]}, "dest":{"uri":["sip:alice@example.com"]},
"iat":1443208345, "iat":1443208345,
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
} }
Single originator, with telephone number identity +12155551212, to The following is an example of a single originator with telephone
multiple destination identities, with telephone number identity number identity +12155551212, to multiple destination identities with
+12125551212 and two URI identities, sip:alice@example.com and telephone number identity +12125551212 and two URI identities --
sip:bob@example.com, example: "sip:alice@example.com" and "sip:bob@example.com":
{ {
"dest":{ "dest":{
"tn":["12125551212"], "tn":["12125551212"],
"uri":["sip:alice@example.com", "uri":["sip:alice@example.com",
"sip:bob@example.net"] "sip:bob@example.net"]
}, },
"iat":1443208345, "iat":1443208345,
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
} }
5.2.2. "mky" - Media Key claim 5.2.2. "mky" (Media Key) Claim
Some protocols that use PASSporT may also want to protect media Some protocols that use PASSporT may also want to protect media
security keys delivered within their signaling in order to bind those security keys delivered within their signaling in order to bind those
keys to the identities established in the signaling layers. The keys to the identities established in the signaling layers. The
"mky" is an optional PASSporT claim defining the assertion of media "mky" claim is an optional PASSporT claim defining the assertion of
key fingerprints carried in SDP [RFC4566] via the "a=fingerprint" media key fingerprints carried in the Session Description Protocol
attribute [RFC4572] Section 5. This claim can support either a (SDP) [RFC4566] via the "a=fingerprint" attribute ([RFC4572],
single or multiple fingerprints appearing in a single SDP body Section 5). This claim can support either a single fingerprint or
corresponding to one or more media streams offered as defined in multiple fingerprints appearing in a single SDP body corresponding to
[I-D.ietf-mmusic-4572-update]. one or more media streams offered as defined in [RFC8122].
The "mky" claim MUST be formatted as a JSON object with an array The "mky" claim MUST be formatted as a JSON object with an array that
including the "alg" and "dig" claims with the corresponding algorithm includes the "alg" and "dig" claims with the corresponding algorithm
and hexadecimal values. If there is more than one fingerprint value and hexadecimal values. If there is more than one fingerprint value
associated with different media streams in SDP, the fingerprint associated with different media streams in SDP, the fingerprint
values MUST be constructed as a JSON array denoted by bracket values MUST be constructed as a JSON array denoted by square brackets
characters. For the "dig" claim, the claim value MUST be the hash ("[" and "]"). For the "dig" claim, the claim value MUST be the hash
hexadecimal value without any colons. of the hexadecimal value without any colons.
The "mky" claim is a JSON object with a claim name of "mky" and a The "mky" claim is a JSON object with a claim name of "mky" and a
claim value of a JSON array denoted by brackets. The "mky" claim claim value of a JSON array denoted by brackets. The "mky" claim
value JSON array MUST be constructed as follows: value JSON array MUST be constructed as follows:
1. Take each "a=fingerprint" lines carried in the SDP. 1. Take each "a=fingerprint" line carried in the SDP.
2. Sort the lines based on the UTF8 encoding of the concatenation of 2. Sort the lines based on the UTF-8 [RFC3629] encoding of the
the "alg" and "dig" claim value strings. concatenation of the "alg" and "dig" claim value strings.
3. Encode the array in the order of the sorted lines, where each 3. Encode the array in the order of the sorted lines, where each
"mky" array element is a JSON object with two elements "mky" array element is a JSON object with two elements
corresponding to the "alg" and "dig" objects, with "alg" first corresponding to the "alg" and "dig" objects, with "alg" first
and "dig" second. and "dig" second.
An example claim with "mky" claim is as follows: An example claim with the "mky" claim is as follows:
For an SDP offer that includes the following fingerprint values, For an SDP offer that includes the following fingerprint values,
a=fingerprint:sha-256 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E: a=fingerprint:sha-256 4A:AD:B9:B1:3F:82:18:3B:54:02:12:DF:3E:
5D:49:6B:19:E5:7C:AB:3E:4B:65:2E:7D:46:3F:54:42:CD:54:F1 5D:49:6B:19:E5:7C:AB:3E:4B:65:2E:7D:46:3F:54:42:CD:54:F1
a=fingerprint:sha-256 02:1A:CC:54:27:AB:EB:9C:53:3F:3E:4B:65 a=fingerprint:sha-256 02:1A:CC:54:27:AB:EB:9C:53:3F:3E:4B:65
:2E:7D:46:3F:54:42:CD:54:F1:7A:03:A2:7D:F9:B0:7F:46:19:B2 :2E:7D:46:3F:54:42:CD:54:F1:7A:03:A2:7D:F9:B0:7F:46:19:B2
the PASSporT Payload object would be: the PASSporT Payload object would be:
skipping to change at page 10, line 26 skipping to change at page 11, line 37
"dig":"4AADB9B13F82183B540212DF3E5D496B19E57C "dig":"4AADB9B13F82183B540212DF3E5D496B19E57C
AB3E4B652E7D463F5442CD54F1" AB3E4B652E7D463F5442CD54F1"
} }
], ],
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
} }
6. PASSporT Signature 6. PASSporT Signature
The signature of the PASSporT is created as specified by JWS The signature of the PASSporT is created as specified by JWS
[RFC7515] Section 5.1 Steps 1 through 6. PASSporT MUST use the JWS ([RFC7515], Section 5.1, Steps 1 through 6). PASSporT MUST use the
Protected Header. For the JWS Payload and the JWS Protected Header, JWS Protected Header. For the JWS Payload and the JWS Protected
the lexicographic ordering and white space rules described in Header, however, the lexicographic ordering and whitespace rules
Section 4 and Section 5, and JSON serialization rules in Section 9 of described in Sections 4 and 5 of this document, and the JSON
this document MUST be followed. serialization rules in Section 9 of this document, MUST be followed.
Appendix A of this document has a detailed example of how to follow Appendix A of this document has a detailed example of how to follow
the steps to create the JWS Signature. the steps to create the JWS Signature.
JWS [RFC7515] Section 5.1 Step 7 JWS JSON serialization is not Step 7 of the JSON serialization procedure in [RFC7515], Section 5.1
supported for PASSporT. is not supported for PASSporT.
JWS [RFC7515] Section 5.1 Step 8 describes the method to create the [RFC7515], Section 5.1, Step 8 describes the method to create the
final JWS Compact Serialization form of the PASSporT Token. final JWS Compact Serialization form of the PASSporT.
7. Compact form of PASSporT 7. Compact Form of PASSporT
For a using protocol of PASSporT, the PASSporT Claims as well as the For a using protocol of PASSporT, the PASSporT claims as well as the
PASSporT Header may include redundant or default information that PASSporT header may include redundant or default information that
could be reconstructed at the destination based on information could be reconstructed at the destination based on information
provided in the signaling protocol transporting the PASSporT object. provided in the signaling protocol transporting the PASSporT object.
In this case, it may be advantageous to have a more compact form of In this case, it may be advantageous to have a more compact form of
PASSporT to save the transmission of the bytes needed to represent PASSporT to save the transmission of the bytes needed to represent
the header and claims. the header and claims.
This specification defines the compact form of the PASSporT token, in This specification defines the compact form of the PASSporT, in the
the spirit of form defined in [RFC7515] Appendix F, with the use of spirit of the form defined in [RFC7515], Appendix F, with the use of
'..', two periods to represent the header and claim objects being two periods ("..") to represent the header and claim objects being
removed, followed by PASSporT signature as defined in Section 6, and removed, followed by the PASSporT signature as defined in Section 6,
the need for the destination to reconstruct the header and claim and the need for the destination to reconstruct the header and claim
objects in order to verify the signature. objects in order to verify the signature.
In order to construct the Compact form of the PASSporT string, the In order to construct the compact form of the PASSporT string, the
procedure described in Section 6 with the exception of Step 8 procedure described in Section 6 MUST be used, with the exception of
described in JWS [RFC7515] Section 5.1. This step would be replaced [RFC7515], Section 5.1, Step 8. This step would be replaced by the
by the following construction of the compact form of PASSporT, following construction of the compact form of PASSporT, ".." ||
'..' || BASE64URL(JWS Signature). BASE64URL(JWS Signature).
The using protocol of the compact form of PASSporT MUST be The using protocol of the compact form of PASSporT MUST be
accompanied by a specification for how the header and claims objects accompanied by a specification for how the header and claims objects
can be reconstructed from information in the signaling protocol being can be reconstructed from information in the signaling protocol being
used. used.
Note that the full form of the PASSporT token, containing the entire Note that the full form of the PASSporT, containing the entire
header, payload, and signature, should also use the lexicographic header, payload, and signature, should also use the lexicographic
ordering and white space serialization rules, particularly in the ordering and whitespace serialization rules, particularly in the case
case where some using protocols or interworking between protocols may where some using protocols or interworking between protocols may
require switching between full and compact forms and maintaining the require switching between full and compact forms and maintaining the
integrity of the signature. integrity of the signature.
7.1. Example Compact form PASSporT Token 7.1. Example Compact Form of PASSporT
The compact form of the following example token (with line breaks The compact form of the following example token (with line breaks
between period used for readability purposes only) between periods used for readability purposes only)
eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j
ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9 ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9
. .
eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI
6IjE0NDMyMDgzNDUiLCJvcmlnIjp7InRuIjoiMTIxNTU1NTEyMTIifX0 6IjE0NDMyMDgzNDUiLCJvcmlnIjp7InRuIjoiMTIxNTU1NTEyMTIifX0
. .
rq3pjT1hoRwakEGjHCnWSwUnshd0-zJ6F1VOgFWSjHBr8Qjpjlk-cpFYpFYsojN rq3pjT1hoRwakEGjHCnWSwUnshd0-zJ6F1VOgFWSjHBr8Qjpjlk-cpFYpFYsojN
CpTzO3QfPOlckGaS6hEck7w CpTzO3QfPOlckGaS6hEck7w
would be as follows (with line breaks between period used for would be as follows:
readability purposes only)
..rq3pjT1hoRwakEGjHCnWSwUnshd0-zJ6F1VOgFWSjHBr8Qjpjlk-cpFYpFYsojN ..rq3pjT1hoRwakEGjHCnWSwUnshd0-zJ6F1VOgFWSjHBr8Qjpjlk-cpFYpFYsojN
CpTzO3QfPOlckGaS6hEck7w CpTzO3QfPOlckGaS6hEck7w
8. Extending PASSporT 8. Extending PASSporT
PASSporT includes the bare minimum set of claims needed to securely PASSporT includes the bare-minimum set of claims needed to securely
assert the originating identity and support the secure properties assert the originating identity and support the secure properties
discussed in various parts of this document. JWT supports a straight discussed in various parts of this document. JWT supports a
forward way to add additional asserted or signed information by straightforward way to add additional asserted or signed information
simply adding new claims. PASSporT can be extended beyond the by simply adding new claims. PASSporT can be extended beyond the
defined base set of claims to represent other information requiring defined base set of claims to represent other information requiring
assertion or validation beyond the originating identity itself as assertion or validation beyond the originating identity itself as
needed. needed.
8.1. "ppt" (PASSporT) header parameter 8.1. "ppt" (PASSporT) Header Parameter
Any using protocol can extend the payload of PASSporT with additional Any using protocol can extend the payload of PASSporT with additional
JWT claims. JWT claims are managed by an existing IANA registry as JWT claims. JWT claims are managed by the "JSON Web Token Claims"
defined in [RFC7519] Section 10.1. Implementations of PASSporT MUST IANA registry as defined in [RFC7519], Section 10.1. Implementations
support the baseline claims defined in Section 5.2, and MAY support of PASSporT MUST support the baseline claims defined in Section 5.2
extended claims. If it is necessary for an extension to PASSporT to and MAY support extended claims. If it is necessary for an extension
require that a relying party support a particular extended claim or to PASSporT to require that a relying party support a particular
set of claims in the PASSporT object, it can do so by specifying a extended claim or set of claims in the PASSporT object, it can do so
"ppt" element for the PASSporT JOSE header. All values of "ppt" need by specifying a "ppt" element for the PASSporT JOSE Header. All
to be defined in a specification which associates the new value of values of "ppt" need to be defined in a specification that associates
the "ppt" element with the required claims and behaviors. Relying the new value of the "ppt" element with the required claims and
parties MUST fail to validate PASSporT objects containing an behaviors. Relying parties MUST fail to validate PASSporT objects
unsupported "ppt". containing an unsupported "ppt".
Using protocols MUST explicitly define the how each claim is carried Using protocols MUST explicitly define how they carry each claim and
in the using protocol and the rules for how the header and payload the rules for how the header and payload objects are constructed
objects are constructed beyond the lexicographical and serialization beyond the lexicographical and serialization rules defined in this
rules defined in this document. document.
Using protocols that carry the compact form of PASSporT, defined in Using protocols that carry the compact form of PASSporT (Section 7)
Section 7, instead of the full form MUST use only mandatory instead of the full form MUST use only mandatory extensions signaled
extensions signaled with "ppt" - if a using protocol were to add with "ppt" -- if a using protocol were to add additional optional
additional optional claims to a PASSporT object it carried in compact claims to a PASSporT object it carried in compact form, relying
form, relying parties would have no way to reconstruct the token. parties would have no way to reconstruct the token. Moreover, using
Moreover, using protocols that support the compact form of PASSporT protocols that support the compact form of PASSporT MUST have some
MUST have some field to signal "ppt" to relying parties, as the field to signal "ppt" to relying parties, as the compact form of
compact form of PASSporT omits the JOSE header. PASSporT omits the JOSE Header.
8.2. Example extended PASSporT header 8.2. Example Extended PASSporT Header
An example header with a PASSporT extension type of "foo" is as An example header with a PASSporT extension type of "foo" is as
follows: follows:
{ {
"alg":"ES256", "alg":"ES256",
"ppt":"foo", "ppt":"foo",
"typ":"passport", "typ":"passport",
"x5u":"https://tel.example.org/passport.cer" "x5u":"https://tel.example.org/passport.cer"
} }
8.3. Extended PASSporT Claims 8.3. Extended PASSporT Claims
Specifications that define extensions to the PASSporT mechanism MUST Specifications that define extensions to the PASSporT mechanism MUST
explicitly specify what claims they include beyond the base set of explicitly specify what claims they include beyond the base set of
claims from this document, the order in which they will appear, and claims from this document, the order in which they will appear, and
any further information necessary to implement the extension. All any further information necessary to implement the extension. All
extensions MUST include the baseline PASSporT claim elements extensions MUST include the baseline PASSporT claim elements
specified in Section 5; claims may only be appended to the claims specified in Section 5; claims may only be appended to the claims
object specified; they can never be removed or re-ordered. object specified; they can never be removed or reordered. Specifying
Specifying new claims follows the baseline JWT procedures ([RFC7519] new claims follows the baseline JWT procedures ([RFC7519],
Section 10.1). Understanding an extension or new claims defined by Section 10.1). Understanding an extension or new claims defined by
the extension on the destination verification of the PASSporT token the extension on the destination verification of the PASSporT is
is optional. The creator of a PASSporT object cannot assume that optional. The creator of a PASSporT object cannot assume that
destination systems will understand any given extension. destination systems will understand any given extension.
Verification of PASSporT tokens by destination systems that do Verification of PASSporTs by destination systems that do support an
support an extension may then trigger appropriate application-level extension may then trigger appropriate application-level behavior in
behavior in the presence of an extension; authors of extensions the presence of an extension; authors of extensions should provide
should provide appropriate extension-specific guidance to application appropriate extension-specific guidance to application developers on
developers on this point. this point.
An example set of extended claims, extending the first example in An example set of extended claims, extending the first example in
Section 5.2.1.4 using "bar" as the newly defined claim would be as Section 5.2.1.4 using "bar" as the newly defined claim, would be as
follows: follows:
{ {
"bar":"beyond all recognition" "bar":"beyond all recognition"
"dest":{"uri":["sip:alice@example.com"]}, "dest":{"uri":["sip:alice@example.com"]},
"iat":1443208345, "iat":1443208345,
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
} }
9. Deterministic JSON Serialization 9. Deterministic JSON Serialization
skipping to change at page 14, line 14 skipping to change at page 15, line 43
3. JSON value literals MUST be lowercase. 3. JSON value literals MUST be lowercase.
4. JSON numbers are to be encoded as integers unless the field is 4. JSON numbers are to be encoded as integers unless the field is
defined to be encoded otherwise. defined to be encoded otherwise.
5. Encoding rules MUST be applied recursively to member values and 5. Encoding rules MUST be applied recursively to member values and
array values. array values.
Note: For any PASSporT extension claims, member names within the Note: For any PASSporT extension claims, member names within the
scope of a JSON object MUST NOT be equal to other member names, scope of a JSON object MUST NOT be equal to other member names;
otherwise serialization will not be deterministic. otherwise, serialization will not be deterministic.
9.1. Example PASSport deterministic JSON form 9.1. Example PASSporT Deterministic JSON Form
This section demonstrate the deterministic JSON serialization for the This section demonstrates the deterministic JSON serialization for
example PASSporT Payload shown in Section 5.2.1.4. the example PASSporT Payload shown in Section 5.2.1.4.
The initial JSON object is shown here: The initial JSON object is shown here:
{ {
"dest":{"uri":["sip:alice@example.com"]}, "dest":{"uri":["sip:alice@example.com"]},
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
"iat":1443208345, "iat":1443208345,
"mky":[ "mky":[
{ {
"alg":"sha-256", "alg":"sha-256",
skipping to change at page 15, line 12 skipping to change at page 17, line 4
Their lexicographic order is: Their lexicographic order is:
o "dest" o "dest"
o "iat" o "iat"
o "mky" o "mky"
o "orig" o "orig"
The final constructed deterministic JSON serialization The final constructed deterministic JSON serialization
representation, with whitespace and line breaks removed, (with line representation, with whitespace and line breaks removed (with line
breaks used for display purposes only) is: breaks used for display purposes only), is:
{"dest":{"uri":["sip:alice@example.com"],"iat":1443208345,"mky": {"dest":{"uri":["sip:alice@example.com"],"iat":1443208345,"mky":
[{"alg":"sha-256","dig":"021ACC5427ABEB9C533F3E4B652E7D463F5442CD5 [{"alg":"sha-256","dig":"021ACC5427ABEB9C533F3E4B652E7D463F5442CD5
4F17A03A27DF9B07F4619B2"},{"alg":"sha-256","dig":"4AADB9B13F82183B5 4F17A03A27DF9B07F4619B2"},{"alg":"sha-256","dig":"4AADB9B13F82183B5
40212DF3E5D496B19E57CAB3E4B652E7D463F5442CD54F1"}], 40212DF3E5D496B19E57CAB3E4B652E7D463F5442CD54F1"}],
"orig":{"tn":"12155551212"}} "orig":{"tn":"12155551212"}}
10. Security Considerations 10. Security Considerations
10.1. Avoidance of replay and cut and paste attacks 10.1. Avoidance of Replay and Cut-and-Paste Attacks
There are a number of security considerations for use of the token There are a number of security considerations regarding the use of
for avoidance of replay and cut and paste attacks. PASSporT tokens the token for the avoidance of replay and cut-and-paste attacks.
SHOULD only be sent with application level protocol information (e.g. PASSporTs SHOULD only be sent with application-level protocol
for SIP an INVITE as defined in [RFC3261]) corresponding to the information (e.g., for SIP, an INVITE as defined in [RFC3261])
required fields in the token. A uniqueness of the set of token corresponding to the required fields in the token. A unique set of
claims and token signature is constructed using the originating token claims and token signature is constructed using the originating
identity being asserted with the 'orig' claim along with the identity being asserted with the "orig" claim along with the
following two claims: following two claims:
o 'iat' claim should correspond to a date/time the message was o The "iat" claim should correspond to a date/time that the message
originated. It should also be within a relative time that is was originated. It should also be within a relative time that is
reasonable for clock drift and transmission time characteristics reasonable for clock drift and transmission time characteristics
associated with the application using the PASSporT token. associated with the application using the PASSporT. Therefore,
Therefore, validation of the token should consider date and time validation of the token should consider date and time correlation,
correlation, which could be influenced by signaling protocol which could be influenced by usage specific to the signaling
specific use and network time differences. protocol and by network time differences.
o 'dest' claim is included to prevent the valid re-use of a o The "dest" claim is included to further restrict the use of a
previously originated message to send to another destination valid PASSporT being sent as a replay attack to other destination
party. parties. The verification of the PASSporT at the destination
should verify that the "dest" claim matches the destination party
as the intended recipient of the message.
10.2. Solution Considerations 10.2. Solution Considerations
The use of PASSporT tokens based on the validation of the digital The use of PASSporTs based on the validation of the digital signature
signature and the associated certificate requires consideration of and the associated certificate requires consideration of the
the authentication and authority or reputation of the signer to authentication and authority or reputation of the signer to attest to
attest to the identity being asserted. The following considerations the identity being asserted. The following considerations should be
should be recognized when using PASSporT: recognized when using PASSporT:
o The use of this token should not, in it's own right, be considered o The use of this token should not, in its own right, be considered
a full solution for absolute non-repudiation of the identity being a full solution for absolute non-repudiation of the identity being
asserted. asserted.
o In many applications, the end user represented by the asserted o In many applications, the signer and the end user represented by
identity represents and signer may not be one in the same. For the asserted identity may not be one and the same. For example,
example, when a service provider signs and validates the token on when a service provider signs and validates the token on behalf of
the behalf of the user consuming the service, the provider MUST the user consuming the service, the provider MUST have an
have an authenticated and secure relationship with the end user or authenticated and secure relationship with the end user or the
the device initiating and terminating the communications device initiating and terminating the communications signaling.
signaling.
o Applications that use PASSporT should ensure the verification of o Applications that use PASSporT should ensure that the verification
the signature includes the means of verifying the signer is of the signature includes a means for verifying that the signer is
authoritative through the use of an application or service authoritative through the use of an application-specific or
specific set of common trust anchors for the application. service-specific set of common trust anchors for the application.
11. IANA Considerations 11. IANA Considerations
11.1. Media Type Registration 11.1. Media Type Registration
11.1.1. Media Type Registry Contents Additions Requested This section registers the "application/passport" media type (see
[RFC2046] for the definition of "media type") in the "Media Types"
This section registers the "application/passport" media type registry in the manner described in [RFC6838], to indicate that the
[RFC2046] in the "Media Types" registry in the manner described in content is a PASSporT-defined JWT.
[RFC6838], which can be used to indicate that the content is a
PASSporT defined JWT.
o Type name: application o Type name: application
o Subtype name: passport o Subtype name: passport
o Required parameters: n/a o Required parameters: N/A
o Optional parameters: n/a o Optional parameters: N/A
o Encoding considerations: 8bit; application/passport values are o Encoding considerations: 8bit; application/passport values are
encoded as a series of base64url-encoded values (some of which may encoded as a series of base64url-encoded values (some of which may
be the empty string) separated by period ('.') characters.. be the empty string) separated by period (".") characters.
o Security considerations: See the Security Considerations o Security considerations: See the Security Considerations section
Section of [RFC7515]. of [RFC7515].
o Interoperability considerations: n/a o Interoperability considerations: N/A
o Published specification: [RFCThis]
o Applications that use this media type: STIR and other applications o Published specification: RFC 8225
that require identity related assertion
o Fragment identifier considerations: n/a o Applications that use this media type: Secure Telephone Identity
Revisited (STIR) and other applications that require
identity-related assertion
o Fragment identifier considerations: N/A
o Additional information: o Additional information:
Magic number(s): n/a File extension(s): n/a Macintosh file type Magic number(s): N/A
code(s): n/a
File extension(s): N/A
Macintosh file type code(s): N/A
o Person & email address to contact for further information: Chris o Person & email address to contact for further information: Chris
Wendt, chris-ietf@chriswendt.net Wendt, chris-ietf@chriswendt.net
o Intended usage: COMMON o Intended usage: COMMON
o Restrictions on usage: none o Restrictions on usage: none
o Author: Chris Wendt, chris-ietf@chriswendt.net o Author: Chris Wendt <chris-ietf@chriswendt.net>
o Change Controller: IESG o Change Controller: IESG
o Provisional registration? No o Provisional registration? No
11.2. JSON Web Token Claims Registration 11.2. Registrations in "JSON Web Token Claims"
11.2.1. Registry Contents Additions Requested
o Claim Name: "orig"
o Claim Description: Originating Identity String
o Change Controller: IESG
o Specification Document(s): Section 5.2.1 of [RFCThis]
o Claim Name: "dest"
o Claim Description: Destination Identity String
o Change Controller: IESG
o Specification Document(s): Section 5.2.1 of [RFCThis]
o Claim Name: "mky"
o Claim Description: Media Key Fingerprint String Claim Name: "orig"
o Change Controller: IESG Claim Description: Originating Identity String
Change Controller: IESG
Reference: Section 5.2.1 of RFC 8225
o Specification Document(s): Section 5.2.2 of [RFCThis] Claim Name: "dest"
Claim Description: Destination Identity String
Change Controller: IESG
Reference: Section 5.2.1 of RFC 8225
11.3. JSON Web Signature and Encryption Header Parameter Registry Claim Name: "mky"
Claim Description: Media Key Fingerprint String
Change Controller: IESG
Reference: Section 5.2.2 of RFC 8225
11.3.1. Registry Contents Additions Requested 11.3. Registration in "JSON Web Signature and Encryption Header
Parameters"
Header Parameter Name: "ppt" Header Parameter Name: "ppt"
Header Parameter Description: PASSporT extension identifier
Header Parameter Usage Location(s): JWS
Change Controller: IESG
Reference: Section 8.1 of RFC 8225
o Header Parameter Description: PASSporT extension identifier 11.4. PASSporT Extensions Registry
o Header Parameter Usage Location(s): JWS
o Change Controller: IESG
o Specification Document(s): Section 8.1 of [RFCThis]
11.4. PASSporT Extension Registry Request
The IANA is requested to create a new PASSporT Type registry for
'ppt' parameter values. That parameter and its values are defined in
Section 8.1. New registry entries must contain the name of the 'ppt'
parameter value and the specification in which the value is
described. The policy for this registry is Specification Required.
12. Acknowledgements
Particular thanks to members of the ATIS and SIP Forum NNI Task Group
including Jim McEchern, Martin Dolly, Richard Shockey, John Barnhill,
Christer Holmberg, Victor Pascual Avila, Mary Barnes, Eric Burger for
their review, ideas, and contributions also thanks to Henning
Schulzrinne, Russ Housley, Alan Johnston, Richard Barnes, Mark
Miller, Ted Hardie, Dave Crocker, Robert Sparks, Jim Schaad for
valuable feedback on the technical and security aspects of the
document. Additional thanks to Harsha Bellur for assistance in
coding the example tokens.
13. References
13.1. Normative References The IANA has created a new PASSporT Type registry for "ppt" parameter
values. That parameter and its values are defined in Section 8.1.
New registry entries must contain the name of the "ppt" parameter
value and the specification in which the value is described. The
policy for this registry is Specification Required [RFC8126].
[I-D.ietf-mmusic-4572-update] 12. References
Lennox, J. and C. Holmberg, "Connection-Oriented Media
Transport over TLS in SDP", draft-ietf-mmusic-
4572-update-13 (work in progress), February 2017.
[I-D.ietf-stir-rfc4474bis] 12.1. Normative References
Peterson, J., Jennings, C., Rescorla, E., and C. Wendt,
"Authenticated Identity Management in the Session
Initiation Protocol (SIP)", draft-ietf-stir-rfc4474bis-15
(work in progress), October 2016.
[RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
Extensions (MIME) Part Two: Media Types", RFC 2046, Extensions (MIME) Part Two: Media Types", RFC 2046,
DOI 10.17487/RFC2046, November 1996, DOI 10.17487/RFC2046, November 1996,
<http://www.rfc-editor.org/info/rfc2046>. <https://www.rfc-editor.org/info/rfc2046>.
[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>.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of
ISO 10646", STD 63, RFC 3629, DOI 10.17487/RFC3629,
November 2003, <https://www.rfc-editor.org/info/rfc3629>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66, Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005, RFC 3986, DOI 10.17487/RFC3986, January 2005,
<http://www.rfc-editor.org/info/rfc3986>. <https://www.rfc-editor.org/info/rfc3986>.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session [RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, DOI 10.17487/RFC4566, Description Protocol", RFC 4566, DOI 10.17487/RFC4566,
July 2006, <http://www.rfc-editor.org/info/rfc4566>. July 2006, <https://www.rfc-editor.org/info/rfc4566>.
[RFC4572] Lennox, J., "Connection-Oriented Media Transport over the [RFC4572] Lennox, J., "Connection-Oriented Media Transport over the
Transport Layer Security (TLS) Protocol in the Session Transport Layer Security (TLS) Protocol in the Session
Description Protocol (SDP)", RFC 4572, Description Protocol (SDP)", RFC 4572,
DOI 10.17487/RFC4572, July 2006, DOI 10.17487/RFC4572, July 2006,
<http://www.rfc-editor.org/info/rfc4572>. <https://www.rfc-editor.org/info/rfc4572>.
[RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type [RFC6838] Freed, N., Klensin, J., and T. Hansen, "Media Type
Specifications and Registration Procedures", BCP 13, Specifications and Registration Procedures", BCP 13,
RFC 6838, DOI 10.17487/RFC6838, January 2013, RFC 6838, DOI 10.17487/RFC6838, January 2013,
<http://www.rfc-editor.org/info/rfc6838>. <https://www.rfc-editor.org/info/rfc6838>.
[RFC6979] Pornin, T., "Deterministic Usage of the Digital Signature [RFC6979] Pornin, T., "Deterministic Usage of the Digital Signature
Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature
Algorithm (ECDSA)", RFC 6979, DOI 10.17487/RFC6979, August Algorithm (ECDSA)", RFC 6979, DOI 10.17487/RFC6979,
2013, <http://www.rfc-editor.org/info/rfc6979>. August 2013, <https://www.rfc-editor.org/info/rfc6979>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web [RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515,
2015, <http://www.rfc-editor.org/info/rfc7515>. May 2015, <https://www.rfc-editor.org/info/rfc7515>.
[RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518, [RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518,
DOI 10.17487/RFC7518, May 2015, DOI 10.17487/RFC7518, May 2015,
<http://www.rfc-editor.org/info/rfc7518>. <https://www.rfc-editor.org/info/rfc7518>.
[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>.
[RFC7638] Jones, M. and N. Sakimura, "JSON Web Key (JWK) [RFC7638] Jones, M. and N. Sakimura, "JSON Web Key (JWK)
Thumbprint", RFC 7638, DOI 10.17487/RFC7638, September Thumbprint", RFC 7638, DOI 10.17487/RFC7638,
2015, <http://www.rfc-editor.org/info/rfc7638>. September 2015, <https://www.rfc-editor.org/info/rfc7638>.
[UNICODE] The Unicode Consortium, "The Unicode Standard", June 2016, [RFC8122] Lennox, J. and C. Holmberg, "Connection-Oriented Media
Transport over the Transport Layer Security (TLS) Protocol
in the Session Description Protocol (SDP)", RFC 8122,
DOI 10.17487/RFC8122, March 2017,
<https://www.rfc-editor.org/info/rfc8122>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in
RFC 2119 Key Words", BCP 14, RFC 8174,
DOI 10.17487/RFC8174, May 2017,
<https://www.rfc-editor.org/info/rfc8174>.
[RFC8224] Peterson, J., Jennings, C., Rescorla, E., and C. Wendt,
"Authenticated Identity Management in the Session
Initiation Protocol (SIP)", RFC 8224,
DOI 10.17487/RFC8224, February 2018,
<https://www.rfc-editor.org/info/rfc8224>.
[UNICODE] The Unicode Consortium, "The Unicode Standard",
<http://www.unicode.org/versions/latest/>. <http://www.unicode.org/versions/latest/>.
13.2. Informative References 12.2. Informative References
[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>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S., [RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008, (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<http://www.rfc-editor.org/info/rfc5280>. <https://www.rfc-editor.org/info/rfc5280>.
[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>.
Appendix A. Example ES256 based PASSporT JWS Serialization and [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>.
Appendix A. Example ES256-Based PASSporT JWS Serialization and
Signature Signature
For PASSporT, there will always be a JWS with the following members: For PASSporT, there will always be a JWS with the following members:
o "protected", with the value BASE64URL(UTF8(JWS Protected Header)) o "protected", with the value BASE64URL(UTF8(JWS Protected Header))
o "payload", with the value BASE64URL (JWS Payload) o "payload", with the value BASE64URL(JWS Payload)
o "signature", with the value BASE64URL(JWS Signature) o "signature", with the value BASE64URL(JWS Signature)
This example will follow the steps in JWS [RFC7515] Section 5.1, This example will follow the steps in JWS ([RFC7515], Section 5.1,
steps 1-6 and 8 and incorporates the additional serialization steps Steps 1-6 and 8); it incorporates the additional serialization steps
required for PASSporT. required for PASSporT.
Step 1 for JWS references the JWS Payload, an example PASSporT Step 1 for JWS references the JWS Payload. An example PASSporT
Payload is as follows: Payload is as follows:
{ {
"dest":{"uri":["sip:alice@example.com"]} "dest":{"uri":["sip:alice@example.com"]}
"iat":1471375418, "iat":1471375418,
"orig":{"tn":"12155551212"} "orig":{"tn":"12155551212"}
} }
This would be serialized to the form (with line break used for This would be serialized to the following form (with line break used
display purposes only): for display purposes only):
{"dest":{"uri":["sip:alice@example.com"]},"iat":1471375418, {"dest":{"uri":["sip:alice@example.com"]},"iat":1471375418,
"orig":{"tn":"12155551212"}} "orig":{"tn":"12155551212"}}
Step 2 Computes the BASE64URL(JWS Payload) producing this value (with Step 2 computes the BASE64URL(JWS Payload), producing this value
line break used for display purposes only): (with line break used for display purposes only):
eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI
6MTQ3MTM3NTQxOCwib3JpZyI6eyJ0biI6IjEyMTU1NTUxMjEyIn19 6MTQ3MTM3NTQxOCwib3JpZyI6eyJ0biI6IjEyMTU1NTUxMjEyIn19
For Step 3, an example PASSporT Protected Header comprising the JOSE For Step 3, an example PASSporT Protected Header constructed as a
Header is as follows: JOSE Header is as follows:
{ {
"alg":"ES256", "alg":"ES256",
"typ":"passport", "typ":"passport",
"x5u":"https://cert.example.org/passport.cer" "x5u":"https://cert.example.org/passport.cer"
} }
This would be serialized to the following form (with line break used
This would be serialized to the form (with line break used for for display purposes only):
display purposes only):
{"alg":"ES256","typ":"passport","x5u":"https://cert.example.org {"alg":"ES256","typ":"passport","x5u":"https://cert.example.org
/passport.cer"} /passport.cer"}
Step 4 Performs the BASE64URL(UTF8(JWS Protected Header)) operation Step 4 performs the BASE64URL(UTF8(JWS Protected Header)) operation
and encoding produces this value (with line break used for display and encoding, producing this value (with line break used for display
purposes only): purposes only):
eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j
ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9 ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9
Step 5 and Step 6 performs the computation of the digital signature Steps 5 and 6 perform the computation of the digital signature of the
of the PASSporT Signing Input ASCII(BASE64URL(UTF8(JWS Protected PASSporT Signing Input ASCII(BASE64URL(UTF8(JWS Protected Header)) ||
Header)) || '.' || BASE64URL(JWS Payload)) using ES256 as the "." || BASE64URL(JWS Payload)), using ES256 as the algorithm and the
algorithm and the BASE64URL(JWS Signature). BASE64URL(JWS Signature).
VLBCIVDCaeK6M4hLJb6SHQvacAQVvoiiEOWQ_iUkqk79UD81fHQ0E1b3_GluIkb VLBCIVDCaeK6M4hLJb6SHQvacAQVvoiiEOWQ_iUkqk79UD81fHQ0E1b3_GluIkb
a7UWYRM47ZbNFdOJquE35cw a7UWYRM47ZbNFdOJquE35cw
Step 8 describes how to create the final PASSporT token,
concatenating the values in the order Header.Payload.Signature with Step 8 describes how to create the final PASSporT, concatenating the
period ('.') characters. For the above example values this would values in the order Header.Payload.Signature with period (".")
produce the following (with line breaks between period used for characters. For the above example values, this would produce the
readability purposes only): following (with line breaks between periods used for readability
purposes only):
eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j eyJhbGciOiJFUzI1NiIsInR5cCI6InBhc3Nwb3J0IiwieDV1IjoiaHR0cHM6Ly9j
ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9 ZXJ0LmV4YW1wbGUub3JnL3Bhc3Nwb3J0LmNlciJ9
. .
eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI eyJkZXN0Ijp7InVyaSI6WyJzaXA6YWxpY2VAZXhhbXBsZS5jb20iXX0sImlhdCI
6MTQ3MTM3NTQxOCwib3JpZyI6eyJ0biI6IjEyMTU1NTUxMjEyIn19 6MTQ3MTM3NTQxOCwib3JpZyI6eyJ0biI6IjEyMTU1NTUxMjEyIn19
. .
VLBCIVDCaeK6M4hLJb6SHQvacAQVvoiiEOWQ_iUkqk79UD81fHQ0E1b3_GluIkb VLBCIVDCaeK6M4hLJb6SHQvacAQVvoiiEOWQ_iUkqk79UD81fHQ0E1b3_GluIkb
a7UWYRM47ZbNFdOJquE35cw a7UWYRM47ZbNFdOJquE35cw
A.1. X.509 Private Key in PKCS#8 format for ES256 Example** A.1. X.509 Private Key in PKCS #8 Format for ES256 Example
-----BEGIN PRIVATE KEY----- -----BEGIN PRIVATE KEY-----
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgi7q2TZvN9VDFg8Vy MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgi7q2TZvN9VDFg8Vy
qCP06bETrR2v8MRvr89rn4i+UAahRANCAAQWfaj1HUETpoNCrOtp9KA8o0V79IuW qCP06bETrR2v8MRvr89rn4i+UAahRANCAAQWfaj1HUETpoNCrOtp9KA8o0V79IuW
ARKt9C1cFPkyd3FBP4SeiNZxQhDrD0tdBHls3/wFe8++K2FrPyQF9vuh ARKt9C1cFPkyd3FBP4SeiNZxQhDrD0tdBHls3/wFe8++K2FrPyQF9vuh
-----END PRIVATE KEY---- -----END PRIVATE KEY-----
A.2. X.509 Public Key for ES256 Example** A.2. X.509 Public Key for ES256 Example
-----BEGIN PUBLIC KEY----- -----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE8HNbQd/TmvCKwPKHkMF9fScavGeH MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAE8HNbQd/TmvCKwPKHkMF9fScavGeH
78YTU8qLS8I5HLHSSmlATLcslQMhNC/OhlWBYC626nIlo7XeebYS7Sb37g== 78YTU8qLS8I5HLHSSmlATLcslQMhNC/OhlWBYC626nIlo7XeebYS7Sb37g==
-----END PUBLIC KEY----- -----END PUBLIC KEY-----
Acknowledgments
Particular thanks to members of the ATIS and SIP Forum NNI Task
Group, including Jim McEachern, Martin Dolly, Richard Shockey, John
Barnhill, Christer Holmberg, Victor Pascual Avila, Mary Barnes, and
Eric Burger, for their review, ideas, and contributions. Thanks also
to Henning Schulzrinne, Russ Housley, Alan Johnston, Richard Barnes,
Mark Miller, Ted Hardie, Dave Crocker, Robert Sparks, and Jim Schaad
for valuable feedback on the technical and security aspects of the
document. Additional thanks to Harsha Bellur for assistance in
coding the example tokens.
Authors' Addresses Authors' Addresses
Chris Wendt Chris Wendt
Comcast Comcast
One Comcast Center One Comcast Center
Philadelphia, PA 19103 Philadelphia, PA 19103
USA United States of America
Email: chris-ietf@chriswendt.net Email: chris-ietf@chriswendt.net
Jon Peterson Jon Peterson
Neustar Inc. Neustar Inc.
1800 Sutter St Suite 570 1800 Sutter St. Suite 570
Concord, CA 94520 Concord, CA 94520
US United States of America
Email: jon.peterson@neustar.biz Email: jon.peterson@neustar.biz
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