Internet DRAFT - draft-ietf-tokbind-ttrp
draft-ietf-tokbind-ttrp
Internet Engineering Task Force B. Campbell
Internet-Draft Ping Identity
Intended status: Standards Track July 5, 2019
Expires: January 6, 2020
HTTPS Token Binding with TLS Terminating Reverse Proxies
draft-ietf-tokbind-ttrp-09
Abstract
This document defines HTTP header fields that enable a TLS
terminating reverse proxy to convey information to a backend server
about the validated Token Binding Message received from a client,
which enables that backend server to bind, or verify the binding of,
cookies and other security tokens to the client's Token Binding key.
This facilitates the reverse proxy and backend server functioning
together as though they are a single logical server side deployment
of HTTPS Token Binding.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 6, 2020.
Copyright Notice
Copyright (c) 2019 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
Campbell Expires January 6, 2020 [Page 1]
Internet-Draft Token Binding and TLS Termination July 2019
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Notation and Conventions . . . . . . . . . . 3
2. HTTP Header Fields and Processing Rules . . . . . . . . . . . 3
2.1. Encoding . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1.1. Token Binding ID . . . . . . . . . . . . . . . . . . 4
2.1.2. Token Binding Type . . . . . . . . . . . . . . . . . 4
2.2. Token Binding ID HTTP Header Fields . . . . . . . . . . . 4
2.3. Processing Rules . . . . . . . . . . . . . . . . . . . . 5
2.4. Examples . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4.1. Provided Token Binding ID . . . . . . . . . . . . . . 6
2.4.2. Provided and Referred Token Binding IDs . . . . . . . 7
2.4.3. Provided and Other Token Binding IDs . . . . . . . . 8
3. TLS Versions and Best Practices . . . . . . . . . . . . . . . 8
4. Security Considerations . . . . . . . . . . . . . . . . . . . 9
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9
5.1. HTTP Message Header Field Names Registration . . . . . . 10
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 10
6.1. Normative References . . . . . . . . . . . . . . . . . . 10
6.2. Informative References . . . . . . . . . . . . . . . . . 11
Appendix A. Acknowledgements . . . . . . . . . . . . . . . . . . 12
Appendix B. Document History . . . . . . . . . . . . . . . . . . 12
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 14
1. Introduction
Token Binding over HTTP [RFC8473] provides a mechanism that enables
HTTP servers to cryptographically bind cookies and other security
tokens to a key generated by the client. When the use of Token
Binding is negotiated in the TLS [RFC5246] handshake [RFC8472] the
client sends an encoded Token Binding Message [RFC8471] as a header
in each HTTP request, which proves possession of one or more private
keys held by the client. The public portion of the keys are
represented in the Token Binding IDs of the Token Binding Message and
for each one there is a signature over some data, which includes the
exported keying material [RFC5705] of the TLS connection. An HTTP
server issuing cookies or other security tokens can associate them
with the Token Binding ID, which ensures those tokens cannot be used
successfully over a different TLS connection or by a different client
than the one to which they were issued.
A fairly common deployment architecture for HTTPS applications is to
have the backend HTTP application servers sit behind a reverse proxy
Campbell Expires January 6, 2020 [Page 2]
Internet-Draft Token Binding and TLS Termination July 2019
that terminates TLS connections from clients. The proxy is
accessible to the internet and dispatches client requests to the
appropriate backend server within a private or protected network.
The backend servers are not directly accessible by clients and are
only reachable through the reverse proxy. The details of such
deployments are typically opaque to clients who make requests to the
proxy server and see responses as though they originated from the
proxy server itself. Although HTTPS is also usually employed between
the proxy and the backend server, the TLS connection that the client
establishes for HTTPS is between itself and the reverse proxy server.
Token Binding facilitates a binding of security tokens to a key held
by the client by way of the TLS connection between that client and
the server. In a deployment where TLS is terminated by a reverse
proxy, however, the TLS connection is between the client and the
proxy while the backend server is likely the system that will issue
and validate cookies or other security tokens. Additional steps are
therefore needed to enable the use of Token Binding in such
deployment architectures. In the absence of a standardized approach,
different implementations will address it differently, which will
make interoperability between such implementations difficult or
impossible without complex configurations or custom integrations.
This document standardizes HTTP header field names that a TLS
terminating reverse proxy (TTRP) adds to requests that it sends to
the backend servers. The headers contain information from the
validated Token Binding Message sent by the client to the proxy, thus
enabling the backend server to bind, or verify the binding of,
cookies and other security tokens to the client's Token Binding key.
The usage of the headers, both the TTRP adding the headers and the
backend application server using the headers to bind cookies or other
tokens, are to be configuration options of the respective systems as
they will not always be applicable.
1.1. Requirements Notation and Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"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.
2. HTTP Header Fields and Processing Rules
Campbell Expires January 6, 2020 [Page 3]
Internet-Draft Token Binding and TLS Termination July 2019
2.1. Encoding
The field-values of the HTTP headers defined herein utilize the
following encoded forms.
2.1.1. Token Binding ID
A Token Binding ID is represented as an "EncodedTokenBindingID",
which is thea base64url encoding of the TokenBindingID byte sequence
(see section 3 of [RFC8471]) using the URL and filename safe alphabet
described in Section 5 of [RFC4648], with all trailing pad characters
'=' omitted and without the inclusion of any line breaks, whitespace,
or other additional characters. ABNF [RFC5234] syntax for
"EncodedTokenBindingID" is shown in Figure 1 below.
EncodedTokenBindingID = *( DIGIT / ALPHA / "-" / "_" )
DIGIT = <Defined in Section B.1 of [RFC5234]>
ALPHA = <Defined in Section B.1 of [RFC5234]>
Figure 1: Encoded Token Binding ID ABNF
2.1.2. Token Binding Type
A Token Binding type value (a single byte) can be represented as an
"EncodedTokenBindingType", which is a case-insensitive hex encoding
(Section 8 of [RFC4648]). The ABNF definition is shown in Figure 2
below.
EncodedTokenBindingType = 1*2HEXDIG
HEXDIG = <Defined in Section B.1 of [RFC5234]>
Figure 2: Encoded Token Binding Type ABNF
2.2. Token Binding ID HTTP Header Fields
The Token Binding Protocol [RFC8471] recommends that implementations
make Token Binding IDs available to the application as opaque byte
sequences, enabling those applications to use the Token Binding IDs
when generating and verifying bound tokens. In the context of a TLS
terminating reverse proxy (TTRP) deployment, the TTRP makes the Token
Binding ID(s) available to the backend application with the following
header fields.
Sec-Provided-Token-Binding-ID
The Token Binding ID of the provided Token Binding represented as
an "EncodedTokenBindingID".
Campbell Expires January 6, 2020 [Page 4]
Internet-Draft Token Binding and TLS Termination July 2019
Sec-Referred-Token-Binding-ID
The Token Binding ID of the referred Token Binding represented as
an "EncodedTokenBindingID".
Sec-Other-Token-Binding-ID
Additional Token Bindings that are sent by the client and
validated by the TTRP are represented as a comma-separated list of
the concatenation of the "EncodedTokenBindingType", a period (".")
character, and the "EncodedTokenBindingID" of each.
Both "Sec-Provided-Token-Binding-ID" and "Sec-Referred-Token-Binding-
ID" are single HTTP header field-valued as defined in Section 3.2 of
[RFC7230], which MUST NOT have a list of values or occur multiple
times in a request.
All header fields defined herein are only for use in HTTP requests
and MUST NOT to be used in HTTP responses.
2.3. Processing Rules
This section defines the applicable processing rules for a TLS
terminating reverse proxy (TTRP) and backend server(s) to provide
server side support of Token Binding over HTTP [RFC8473] using the
HTTP headers described in Section 2.2. Use of the technique is to be
a configuration or deployment option and the processing rules
described herein are for servers operating with that option enabled.
A TTRP negotiates the use of Token Binding with the client, such as
is described in [RFC8472] and validates the Token Binding Message as
defined in The Token Binding Protocol [RFC8471] and Token Binding
over HTTP [RFC8473] for each HTTP request on the underlying TLS
connection. Requests with a valid Token Binding Message (and meeting
any other authorization or policy requirements of the TTRP) are
dispatched to the backend server with the following modifications.
1. The "Sec-Token-Binding" header in the original incoming request
MUST be removed from the request that is dispatched to the
backend server.
2. The Token Binding ID of the provided Token Binding of the Token
Binding Message MUST be placed in the "Sec-Provided-Token-
Binding-ID" header field of the dispatched request using the
format defined in Section 2.2.
3. If the Token Binding Message contains a referred Token Binding,
the referred Token Binding ID MUST be placed in the "Sec-
Referred-Token-Binding-ID" header field of the dispatched request
using the format defined in Section 2.2. Otherwise, the "Sec-
Campbell Expires January 6, 2020 [Page 5]
Internet-Draft Token Binding and TLS Termination July 2019
Referred-Token-Binding-ID" header field MUST NOT be present in
the dispatched request.
4. If the Token Binding Message contains any additional validated
Token Bindings, they are placed in the "Sec-Other-Token-Binding-
ID" header field using the format defined in Section 2.2. If the
Token Binding Message contains no additional valid Token
Bindings, the "Sec-Referred-Token-Binding-ID" header field MUST
NOT be present in the dispatched request.
5. Any occurrence of the "Sec-Provided-Token-Binding-ID", "Sec-
Referred-Token-Binding-ID", and "Sec-Other-Token-Binding-ID"
headers in the original incoming request MUST be removed or
overwritten before forwarding the request.
Requests made over a connection where the use of Token Binding was
not negotiated MUST be sanitized by removing any occurrences of the
"Sec-Provided-Token-Binding-ID", "Sec-Referred-Token-Binding-ID", and
"Sec-Other-Token-Binding-ID" header fields prior to dispatching the
request to the backend server.
Forward proxies and other intermediaries MUST NOT add the "Sec-
Provided-Token-Binding-ID" "Sec-Referred-Token-Binding-ID", or "Sec-
Other-Token-Binding-ID" header to requests.
2.4. Examples
Extra line breaks and whitespace have been added to the following
examples for display and formatting purposes only.
2.4.1. Provided Token Binding ID
The following "Sec-Token-Binding" header is from an HTTP request made
over a TLS connection between the client and the TTRP where the use
of Token Binding has been negotiated. The base64url-encoded
representation of the exported keying material for that connection is
"AYVUayPTP9RmELNpGjFl6Ykm2CUx7pUMxe35yb11dgU", which can be used to
validate the Token Binding Message. The encoded Token Binding
Message has the provided Token Binding that the client uses with the
server.
Sec-Token-Binding: AIkAAgBBQKzyIrmcY_YCtHVoSHBut69vrGfFdy1_YKTZfFJv
6BjrZsKD9b9FRzSBxDs1twTqnAS71M1RBumuihhI9xqxXKkAQEtxe4jeUJU0WezxlQ
XWVSBFeHxFMdXRBIH_LKOSAuSMOJ0XEw1Q8DE248qkOiRKzw3KdSNYukYEPmO21bQi
3YYAAA
Figure 3: Header in HTTP Request to TTRP
Campbell Expires January 6, 2020 [Page 6]
Internet-Draft Token Binding and TLS Termination July 2019
After validating the Token Binding Message, the TTRP removes the
"Sec-Token-Binding" header and adds the following "Sec-Provided-
Token-Binding-ID" header with the provided Token Binding ID to the
request that is dispatched to the backend server.
Sec-Provided-Token-Binding-ID: AgBBQKzyIrmcY_YCtHVoSHBut69vrGfFdy1_
YKTZfFJv6BjrZsKD9b9FRzSBxDs1twTqnAS71M1RBumuihhI9xqxXKk
Figure 4: Header in HTTP Request to Backend Server
2.4.2. Provided and Referred Token Binding IDs
The following "Sec-Token-Binding" header is from an HTTP request made
over a TLS connection between the client and the TTRP where the use
of Token Binding has been negotiated. The base64url-encoded
representation of the exported keying material for that connection is
"wEWWCP1KPxfq-QL4NxYII_P4ti_9YYqrTpGs28BZEqE", which can be used to
validate the Token Binding Message. The encoded Token Binding
Message has the provided Token Binding that the client uses with the
server as well as the referred Token Binding that it uses with a
different server.
Sec-Token-Binding: ARIAAgBBQCfsI1D1sTq5mvT_2H_dihNIvuHJCHGjHPJchPav
NbGrOo26-2JgT_IsbvZd4daDFbirYBIwJ-TK1rh8FzrC-psAQMyYIqXj7djGPev1dk
jV9XxLYGCyqOrBVEtBHrMUCeo22ymLg3OiFcl_fmOPxJbjxI6lKcF0lyfy-dSQmPIe
zQ0AAAECAEFArPIiuZxj9gK0dWhIcG63r2-sZ8V3LX9gpNl8Um_oGOtmwoP1v0VHNI
HEOzW3BOqcBLvUzVEG6a6KGEj3GrFcqQBAHQm0pzgUTXKLRamuKE1pmmP9I3UBVpoe
1DBCe9H2l1VPpsImakUa6crAqZ-0CGBmji7bYzQogpKcyxTTFk5zdwAA
Figure 5: Header in HTTP Request to TTRP
After validating the Token Binding Message, the TTRP removes the
"Sec-Token-Binding" header and adds the following "Sec-Provided-
Token-Binding-ID" and "Sec-Referred-Token-Binding-ID" headers, with
the provided and referred Token Binding IDs respectively, to the
request that is dispatched to the backend server.
Sec-Provided-Token-Binding-ID: AgBBQCfsI1D1sTq5mvT_2H_dihNIvuHJCHGj
HPJchPavNbGrOo26-2JgT_IsbvZd4daDFbirYBIwJ-TK1rh8FzrC-ps
Sec-Referred-Token-Binding-ID: AgBBQKzyIrmcY_YCtHVoSHBut69vrGfFdy1_
YKTZfFJv6BjrZsKD9b9FRzSBxDs1twTqnAS71M1RBumuihhI9xqxXKk
Figure 6: Headers in HTTP Request to Backend Server
Campbell Expires January 6, 2020 [Page 7]
Internet-Draft Token Binding and TLS Termination July 2019
2.4.3. Provided and Other Token Binding IDs
The following "Sec-Token-Binding" header is from an HTTP request made
over a TLS connection between the client and the TTRP where the use
of Token Binding has been negotiated. The base64url-encoded
representation of the exported keying material for that connection is
"Zr_1DESCcDoaltcZCK613UrEWHRf2B3w9i3bwcxpacc", which can be used to
validate the Token Binding Message. The encoded Token Binding
Message has the provided Token Binding and two other Token Bindings.
Sec-Token-Binding: AZsAAgBBQA35hcCjI5GEHLLAZ0i2l2ZvQe-bSPAP7jovkZJM
4wYHgmmXNd1aRpnQmXK9ghUmrdtS6p_e2uSlMXIVKOIwgysAQJ-TKyVGF37XUXMy79
ybwJyPpfCG9Iq6fdIxLX_yJn-L__Z3p_WIL3g17K0OH3XZmJS3qZNNEVu_8HmPN-d9
hGMAAE0CAEFAR68GbdIQyrHqkorJF0sekYJvf8iV03obGxbaWbqAEJetsYxprB6c3M
x5KDHBGZjsFbeFW5Xec_EaxX0Hw3RmJwBA-Fu22kokRbB7G0D0g6_sdCHTbczSCmnm
6rqP1x7kRIIj_kJNCCWcwMMFzbsBTXcm5fJrRdBTcsqiiqYD6aJ1SgAACwIAQUCDqt
6m63By8b1lvhN-n9OsQThoLomzKpMicSZGwR166jplhbkjrFsHzdNqzLFFEhCT9s0p
XrcbpOHsZnpRSkmhAEBfOwxjK3Y9EOeMrqjo0IUhmurW2EgtSRBjDwc0r-rDT231Zv
_f1oePB8Pkd1kgAtgKX5EDiemfo1YER3_I2cv3AAA
Figure 7: Header in HTTP Request to TTRP
After validating the Token Binding Message, the TTRP removes the
"Sec-Token-Binding" header and adds the following "Sec-Provided-
Token-Binding-ID" and "Sec-Other-Token-Binding-ID" headers to the
request that is dispatched to the backend server.
Sec-Provided-Token-Binding-ID: AgBBQA35hcCjI5GEHLLAZ0i2l2ZvQe-bSPAP
7jovkZJM4wYHgmmXNd1aRpnQmXK9ghUmrdtS6p_e2uSlMXIVKOIwgys
Sec-Other-Token-Binding-ID: 4d.AgBBQEevBm3SEMqx6pKKyRdLHpGCb3_IldN6
GxsW2lm6gBCXrbGMaawenNzMeSgxwRmY7BW3hVuV3nPxGsV9B8N0Zic,B.AgBBQIO
q3qbrcHLxvWW-E36f06xBOGguibMqkyJxJkbBHXrqOmWFuSOsWwfN02rMsUUSEJP2
zSletxuk4exmelFKSaE
Figure 8: Headers in HTTP Request to Backend Server
3. TLS Versions and Best Practices
TLS 1.2 [RFC5246] is cited in this document because, at the time of
writing, it is the latest version that is widely deployed. However,
this document is applicable with other TLS versions that allow for
negotiating the use of Token Binding. Token Binding for Transport
Layer Security (TLS) Version 1.3 Connections
[I-D.ietf-tokbind-tls13], for example, describes Token Binding with
TLS 1.3 [RFC8446]. Implementation security considerations for TLS,
including version recommendations, can be found in Recommendations
for Secure Use of Transport Layer Security (TLS) and Datagram
Transport Layer Security (DTLS) [BCP195].
Campbell Expires January 6, 2020 [Page 8]
Internet-Draft Token Binding and TLS Termination July 2019
4. Security Considerations
The headers described herein enable a reverse proxy and backend
server to function together as though they are a single logical
server side deployment of HTTPS Token Binding. Use of the headers
outside that intended use case, however, may undermine the
protections afforded by Token Binding. Therefore steps MUST be taken
to prevent unintended use, both in sending the headers and in relying
on their value.
Producing and consuming the headers SHOULD be a configurable option,
respectively, in a reverse proxy and backend server (or individual
application in that server). The default configuration for both
should be to not use the headers thus requiring an "opt-in" to the
functionality.
Backend servers MUST only accept the headers from trusted reverse
proxies. And reverse proxies MUST sanitize the incoming request
before forwarding it on by removing or overwriting any existing
instances of the headers. Otherwise arbitrary clients can control
the header values as seen and used by the backend server.
The communication between a reverse proxy and backend server needs to
be secured against eavesdropping and modification by unintended
parties.
The configuration options and request sanitization are necessarily
functionally of the respective servers. The other requirements can
be met in a number of ways, which will vary based on specific
deployments. The communication between a reverse proxy and backend
server, for example, might be over a mutually authenticated TLS with
the insertion and consumption headers occurring only on that
connection. Alternatively the network topology might dictate a
private network such that the backend application is only able to
accept requests from the reverse proxy and the proxy can only make
requests to that server. Other deployments that meet the
requirements set forth herein are also possible.
Employing the "Sec-" header field prefix for the headers defined
herein denotes them as forbidden header names (see [fetch-spec]),
which means they cannot be set or modified programmatically by script
running in-browser.
5. IANA Considerations
Campbell Expires January 6, 2020 [Page 9]
Internet-Draft Token Binding and TLS Termination July 2019
5.1. HTTP Message Header Field Names Registration
This document specifies the following new HTTP header fields,
registration of which is requested in the "Permanent Message Header
Field Names" registry defined in [RFC3864].
o Header Field Name: "Sec-Provided-Token-Binding-ID"
o Applicable protocol: HTTP
o Status: standard
o Author/change Controller: IETF
o Specification Document(s): [[ this specification ]]
o Header Field Name: "Sec-Referred-Token-Binding-ID"
o Applicable protocol: HTTP
o Status: standard
o Author/change Controller: IETF
o Specification Document(s): [[ this specification ]]
o Header Field Name: "Sec-Other-Token-Binding-ID"
o Applicable protocol: HTTP
o Status: standard
o Author/change Controller: IETF
o Specification Document(s): [[ this specification ]]
6. References
6.1. Normative References
[BCP195] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <http://www.rfc-editor.org/info/bcp195>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, DOI 10.17487/RFC4648, October 2006,
<https://www.rfc-editor.org/info/rfc4648>.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234,
DOI 10.17487/RFC5234, January 2008,
<https://www.rfc-editor.org/info/rfc5234>.
Campbell Expires January 6, 2020 [Page 10]
Internet-Draft Token Binding and TLS Termination July 2019
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<https://www.rfc-editor.org/info/rfc5246>.
[RFC5705] Rescorla, E., "Keying Material Exporters for Transport
Layer Security (TLS)", RFC 5705, DOI 10.17487/RFC5705,
March 2010, <https://www.rfc-editor.org/info/rfc5705>.
[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[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>.
[RFC8471] Popov, A., Ed., Nystroem, M., Balfanz, D., and J. Hodges,
"The Token Binding Protocol Version 1.0", RFC 8471,
DOI 10.17487/RFC8471, October 2018,
<https://www.rfc-editor.org/info/rfc8471>.
[RFC8472] Popov, A., Ed., Nystroem, M., and D. Balfanz, "Transport
Layer Security (TLS) Extension for Token Binding Protocol
Negotiation", RFC 8472, DOI 10.17487/RFC8472, October
2018, <https://www.rfc-editor.org/info/rfc8472>.
[RFC8473] Popov, A., Nystroem, M., Balfanz, D., Ed., Harper, N., and
J. Hodges, "Token Binding over HTTP", RFC 8473,
DOI 10.17487/RFC8473, October 2018,
<https://www.rfc-editor.org/info/rfc8473>.
6.2. Informative References
[fetch-spec]
WhatWG, "Fetch", Living Standard ,
<https://fetch.spec.whatwg.org/>.
[I-D.ietf-tokbind-tls13]
Harper, N., "Token Binding for Transport Layer Security
(TLS) Version 1.3 Connections", draft-ietf-tokbind-
tls13-01 (work in progress), May 2018.
[RFC3864] Klyne, G., Nottingham, M., and J. Mogul, "Registration
Procedures for Message Header Fields", BCP 90, RFC 3864,
DOI 10.17487/RFC3864, September 2004,
<https://www.rfc-editor.org/info/rfc3864>.
Campbell Expires January 6, 2020 [Page 11]
Internet-Draft Token Binding and TLS Termination July 2019
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
Appendix A. Acknowledgements
The author would like to thank the following people for their various
contributions to the specification: Vinod Anupam, Dirk Balfanz, John
Bradley, William Denniss, Nick Harper, Jeff Hodges, Subodh Iyengar,
Leif Johansson, Michael B. Jones, Yoav Nir, James Manger, Andrei
Popov, Eric Rescorla, Piotr Sikora, Martin Thomson, and Hans Zandbelt
Appendix B. Document History
[[ to be removed by the RFC Editor before publication as an RFC ]]
draft-ietf-tokbind-ttrp-09
o Publishing with no changes from -07/-08 to have a non expired
version up while still awaiting the shepherd writeup.
draft-ietf-tokbind-ttrp-08
o Avoid impending expiration (while awaiting the shepherd writeup)
by publishing with no changes from -07.
draft-ietf-tokbind-ttrp-07
o Update TLS 1.3 reference to RFC 8446.
o Update the references to the core token binding specs, which are
now RFCs 8471, 8472, and 8473.
draft-ietf-tokbind-ttrp-06
o Move TLS Versions and Best Practices out of Security
Considerations to its own top-level section.
draft-ietf-tokbind-ttrp-05
o Editorial updates.
o Change one character in the last example to help emphasize the
case-insensitivity of hex.
o Add a TLS Versions and Best Practices section with BCP195 and also
mention of ietf-tokbind-tls13 and ietf-tls-tls13.
Campbell Expires January 6, 2020 [Page 12]
Internet-Draft Token Binding and TLS Termination July 2019
draft-ietf-tokbind-ttrp-04
o Add an example with Sec-Other-Token-Binding-ID.
o Use the HEXDIG core ABNF rule for EncodedTokenBindingType and
mention case-insensitive in the text.
o Minor editorial fixes.
o Add to the Acknowledgements and remove the 'and others' bit.
draft-ietf-tokbind-ttrp-03
o Add a header to allow for additional token binding types other
than provided and referred to be conveyed.
o Reword the Abstract somewhat for (hopefully) improved readability.
o Minor editorial and formatting updates.
draft-ietf-tokbind-ttrp-02
o Add to the Acknowledgements.
o Update references for Token Binding negotiation, protocol, and
https.
o Use the boilerplate from RFC 8174.
o Reformat the "HTTP Header Fields and Processing Rules" section to
make the header names more prominent and move the encoding
definitions earlier.
draft-ietf-tokbind-ttrp-01
o Prefix the header names with "Sec-" so that they are denoted as
forbidden header names by Fetch https://fetch.spec.whatwg.org/
o Removed potentially confusing sentence from Security
Considerations per
https://mailarchive.ietf.org/arch/msg/unbearable/
O0IpppyyEqMrQjEkyEi8p8CeBGA
o Editorial fixes.
draft-ietf-tokbind-ttrp-00
o Initial WG draft from draft-campbell-tokbind-ttrp.
Campbell Expires January 6, 2020 [Page 13]
Internet-Draft Token Binding and TLS Termination July 2019
draft-campbell-tokbind-ttrp-01
o Minor editorial fixes.
o Add to the Acknowledgements.
draft-campbell-tokbind-ttrp-00
o Initial draft based on 'consensus to work on the problem' from the
Seoul meeting [1][2] and reflecting the consensus approach from
discussions at the Chicago meeting [3].
[1] https://www.ietf.org/proceedings/97/minutes/minutes-97-
tokbind-01.txt (minutes from Seoul)
[2] https://www.ietf.org/proceedings/97/slides/slides-97-tokbind-
reverse-proxies-00.pdf (slides from Seoul)
[3] https://mailarchive.ietf.org/arch/msg/
unbearable/_ZHI8y2Vs5WMP8VMRr7zroo_sNU (summary of discussion)
Author's Address
Brian Campbell
Ping Identity
Email: brian.d.campbell@gmail.com
Campbell Expires January 6, 2020 [Page 14]
