Internet DRAFT - draft-hallambaker-wsconnect
draft-hallambaker-wsconnect
Internet Engineering Task Force (IETF) Phillip Hallam-Baker
Internet-Draft Comodo Group Inc.
Intended Status: Standards Track May 19, 2014
Expires: November 20, 2014
Service Connection Service (SXS)
draft-hallambaker-wsconnect-08
Abstract
Service Connection Service (SXS) is a JSON/REST Web Service that may
be used to establish and maintain a 'connection binding' of a device
to an account held with a Web Service Provider. Multiple connection
bindings may be established under the same account to support
multiple devices and/or multiple users of a single device. A
connection binding permits a device to securely connect to one or
more services offered by the Web Service Provider with support for
protocol and protocol version agilty and fault tollerance.
The protocol is presented as a HTTP/JSON Web Service and uses the
HTTP session continuation mechanism for authentication of transaction
messages and supports negotiation of a HTTP session continuation
mechanism context for the established endpoint connections.
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
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Copyright Notice
Copyright (c) 2014 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
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
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described in the Simplified BSD License.
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Table of Contents
1. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.1. Requirements Language . . . . . . . . . . . . . . . . . . 5
2. Introduction and Purpose . . . . . . . . . . . . . . . . . . . 5
2.1. Establishing a Web Service Provider Account . . . . . . . 5
2.2. Establishing a Connection Binding . . . . . . . . . . . . 6
2.2.1. Anonymous. . . . . . . . . . . . . . . . . . . . . . 7
2.2.2. PIN Code Establishement. . . . . . . . . . . . . . . 8
2.2.3. Out of Band Completion. . . . . . . . . . . . . . . 8
2.2.4. QR Code Preauthorization. . . . . . . . . . . . . . 9
3. Example Uses . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1. PIN code establishment . . . . . . . . . . . . . . . . . 9
3.2. Unbinding . . . . . . . . . . . . . . . . . . . . . . . . 14
3.3. Out of Band Completion . . . . . . . . . . . . . . . . . 15
3.3.1. Message: Message . . . . . . . . . . . . . . . . . . 17
3.3.2. Message: Response . . . . . . . . . . . . . . . . . 17
3.3.3. Message: ConnectionRequest . . . . . . . . . . . . . 17
3.3.4. Structure: Cryptographic . . . . . . . . . . . . . . 17
3.3.5. Structure: ImageLink . . . . . . . . . . . . . . . . 18
3.3.6. Structure: Connection . . . . . . . . . . . . . . . 18
4. OBPConnection . . . . . . . . . . . . . . . . . . . . . . . . 18
4.1. Bind . . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.1.1. Message: BindRequest . . . . . . . . . . . . . . . . 19
4.2. BindPIN . . . . . . . . . . . . . . . . . . . . . . . . . 19
4.2.1. Message: OpenPINRequest . . . . . . . . . . . . . . 19
4.2.2. Message: OpenPINResponse . . . . . . . . . . . . . . 20
4.3. Poll . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.3.1. Message: PollRequest . . . . . . . . . . . . . . . . 21
4.4. Ticket . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.4.1. Message: TicketRequest . . . . . . . . . . . . . . . 21
4.4.2. Message: TicketResponse . . . . . . . . . . . . . . 21
4.5. Unbind . . . . . . . . . . . . . . . . . . . . . . . . . 22
4.5.1. Message: UnbindRequest . . . . . . . . . . . . . . . 22
4.5.2. Message: UnbindResponse . . . . . . . . . . . . . . 22
5. Mutual Authentication . . . . . . . . . . . . . . . . . . . . 22
5.1. PIN Authentication . . . . . . . . . . . . . . . . . . . 22
5.1.1. Example: Latin PIN Code . . . . . . . . . . . . . . 25
5.1.2. Example: Cyrillic PIN Code . . . . . . . . . . . . . 25
5.2. Out of Band Confirmation . . . . . . . . . . . . . . . . 26
6. Protocol Binding . . . . . . . . . . . . . . . . . . . . . . . 27
6.1. JSON encoding . . . . . . . . . . . . . . . . . . . . . . 27
6.1.1. HTTP Session Layer . . . . . . . . . . . . . . . . . 27
6.1.2. TLS transport . . . . . . . . . . . . . . . . . . . 28
7. Service Identification and Discovery . . . . . . . . . . . . . 28
8. UDP Binding (UYFM) . . . . . . . . . . . . . . . . . . . . . . 29
8.1. Request . . . . . . . . . . . . . . . . . . . . . . . . . 29
8.2. Response . . . . . . . . . . . . . . . . . . . . . . . . 30
8.3. Payload . . . . . . . . . . . . . . . . . . . . . . . . . 31
9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 32
10. Security Considerations . . . . . . . . . . . . . . . . . . . 32
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10.1. Denial of Service . . . . . . . . . . . . . . . . . . . 32
10.2. Breach of Trust . . . . . . . . . . . . . . . . . . . . 32
10.3. Coercion . . . . . . . . . . . . . . . . . . . . . . . . 32
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 32
12. Stateless server . . . . . . . . . . . . . . . . . . . . . . 32
12.1. Temporary ID . . . . . . . . . . . . . . . . . . . . . . 33
12.2. Connection Binding ID . . . . . . . . . . . . . . . . . 34
13. References . . . . . . . . . . . . . . . . . . . . . . . . . 35
13.1. Normative References . . . . . . . . . . . . . . . . . . 35
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 36
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1. Definitions
1.1. Requirements Language
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
2. Introduction and Purpose
Service Connection Service (SXS) is a Web Service that may be used to
establish and maintain a 'connection binding' of a device to an
account held with a Web Service Provider (WSP).
SXS is presented in JSON encoding [RFC4627] over a HTTP Session
[RFC2616] using HTTP Session Continuation [I-D.hallambaker-
httpsession] for message layer authentication and TLS transport for
confidentiality and server authentication [RFC4627].
A Connection Binding comprises a set of long term credentials used to
authenticate interactions with the SXS service itself and a set of
'Service Connections' to specific services offered by the Web Service
Provider.
Each service connection in turn comprises a collection of 'Instance
Connections' which describe a specific instances of the Web Service.
For example Alice is a consumer and example.com a provider of a range
of Web Services including anti-malware protection and management of
home automation devices. Alice has 42 devices of different types that
each make use of one or more of the Web Services proviced by
example.com. All the devices are enrolled in the same SXS account
'alice@example.com' but each device has a unique connection binding
and different devices make use of different Web Services.
The centralized account provides Alice with a single point of control
from which she can authorize the addition of new devices to the
account or the removal of devices that are deactivated. This allows
Alice to avoid the need to manage a device such as a network-enabled
lightswitch through the lightswitch itself.
To ensure continuity of service in case of network failure or
administration work, example.com provides multiple instances of its
Web Services hosted on different machines. Different users MAY be
granted access to a different collection of service instances
according to their needs and the service tier they are subscribed to.
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2.1. Establishing a Web Service Provider Account
The means by which the Web Service Provider Account is established is
outside the scope of this document.
In a typical case the user would establish an account with their
chosen Web Service Provider through the normal process of using a Web
Browser to access the Web Service Provider's site and entering such
data as the Web Service Provider requires into a HTML form.
Depending on the circumstances, the data provided by the applicant
may require verification before the account is created.
[Default accounts for appliances that are going to be implicitly
authenticated by reference to the network they are on.]
2.2. Establishing a Connection Binding
A connection binding represents a long term association between a
device and an account at the Web Service Provider. The association
includes the establishment of an authentication context between the
device and the SXS service.
An authentication context consists of: A Context Identifier. An
authentication algorithm. A secret key.
The context identifier is an opaque string assigned by the SXS
service. Following the approach introduced in Kerberos, a SXS service
MAY eliminate the need to store authentication context information by
encoding the authentication algorithm and encrypted secret key in the
context identifier.
The authentication context can ensure that future communications are
secured against impersonation if and only if the original process of
establishing a connection binding was secured against communication.
Mutual authentication is therefore an essential requirement.
The means by which the connection binding is established depend on
the affordances of the device in question. Establishing a connection
binding to a device with a keyboard is easily accomplished through
use of a one-time PIN code. But many embedded devices do not provide
a keyboard or similar affordance.
The following modes of session establishement are supported:
* Anonymous.
* PIN Code Establishement.
* Out of Band Completion.
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* QR Code Establishement.
2.2.1. Anonymous.
Private-DNS [I-D.hallambaker-privatedns] provides a means of making
DNS queries over a UYFM transport providing integrity and
confidentiality protections.
To establish a Private-DNS connection, a client first establishes a
SXS connection binding to the service. A Private-DNS service MAY
offer such services without requiring presentation or authentication
of credentials. The BindRequest transaction is used as follows:
POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Host: localhost:8080
Content-Length: 226
Expect: 100-continue
{
"BindRequest": {
"Service": ["private-dns-resolver"],
"Encryption": ["A128CBC",
"A256CBC",
"A128GCM",
"A256GCM"],
"Authentication": ["HS256",
"HS384",
"HS512",
"HS256T128"]}}
Since the service does not require authentication, the request is
granted immediately and the necessary host connection parameters
returned immediately:
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HTTP/1.1 OK Success
Content-Length: 578
Date: Mon, 19 May 2014 17:17:44 GMT
Server: Microsoft-HTTPAPI/2.0
{
"TicketResponse": {
"Status": 200,
"StatusDescription": "Success",
"Cryptographic": [],
"Service": [{
"Service": "private-dns-resolver",
"Name": "localhost",
"Port": 9090,
"Priority": 100,
"Weight": 100,
"Transport": "UDP",
"Cryptographic": {
"Secret": "
WAX8Zj_oNmf7zI7uBlupQA",
"Encryption": "A128CBC",
"Authentication": "HS256T128",
"Ticket": "
Samh8lKlrNRaNZ6wQLMDGfqiUpc8dIBnYRutTu5g4RifL4CgwjMiGmCbHc4ZUiMd
-Yf_oUGRDnU05LwW0_8GyU_1X7dTyPPqNwvQyyZ_IoM"}}]}}
2.2.2. PIN Code Establishement.
To establish a connection binding for a new mobile phone, Alice logs
into her SXS account manager and requests a new PIN code. She then
starts the application that makes use of a SXS account and selects
'create new binding'. She is prompted for and enters her account name
(alice@example.com) and PIN.
The client connects to the SXS service and verifies that the TLS
certificate presented is correct for example.com and has been issued
in accordance with issue practices that ensure an appropriately high
degree of trust (e.g. the CABForum Extended Validation requirements).
2.2.3. Out of Band Completion.
To establish a connection binding for her new toaster oven, Alice
plugs the appliance into her local network and enters her account
name into the device. Since she has not obtained a PIN code in
advance, she leaves the entry blank.
To complete the process, Alice logs into her SXS account where she
sees that a new device is available to add to the account. To help
identify the correct device, there is a picture of the toaster oven,
the model name and serial number.
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2.2.4. QR Code Preauthorization.
Alice decides to remodel the kitchen completely and plans to install
a dozen new network enabled LED light fixtures. Using an application
on the mobile phone she enabled earlier, Alice scans a QR code
attached to each fixture before the devices are installed. When the
fixtures are installed and powered, the connection binding is
preauthorized.
3. Example Uses
3.1. PIN code establishment
Alice buys a new laptop computer which she wishes to use with the
malware protection service provided by example.com. Alice has an
existing account 'alice' with this Web Service Provider and obtains a
pin code Q80370-1RA606-F04B from the Web Service Provider Web site.
Alice enters the values alice@example.com and Q80370-1RA606-F04B into
the Web Service client she wishes to use with the Web Service
Provider on the new laptop.
The client obtains the SXS service for example.com using DNS SRV
discovery. The client establishes a TLS connection to the service and
verifies that the certificate provided has a valid certificate path,
has not been revoked and meets the validation criteria of the client.
Since the purpose of this particular Web Service client is to provide
security, the client requires that an Extended Validation certificate
be presented.
Having established a TLS connection to the SXS Service, the client
sends the following HTTP request:
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POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Host: localhost:8080
Content-Length: 368
Expect: 100-continue
Connection: Keep-Alive
{
"OpenPINRequest": {
"Encryption": ["A128CBC",
"A256CBC",
"A128GCM",
"A256GCM"],
"Authentication": ["HS256",
"HS384",
"HS512",
"HS256T128"],
"Account": "alice",
"Service": ["sxs-confirm-user",
"omni-query"],
"Domain": "example.com",
"HaveDisplay": false,
"Challenge": "
BOen_kEze3TJi7nW6zO73A"}}
To prevent man in the middle attack, the client does not send the PIN
code in the initial request. The PIN code is only sent after the
service responds with a challenge nonce to be used to prevent replay
attack.
The service receives the request, determines that is meets its access
control policy and selects a set of cryptographic parameters from the
set proposed by the client. In this case the service prefers the use
of AES128CBC for encryption and the HS256 Message Authentication Code
for authentication.
The service determines that a PIN code has been issued for the
account and uses the value of that PIN to generate a response to the
challenge presented by the client. A new challenge is generated to
test the client knowledge of the PIN.
[TBS: Is there a need for the service to be able to support multiple
outstanding PIN codes for the same account? This could be supported
by providing the last 2 significant characters of the PIN code to the
service which could use it as an index. This would enable several
hundred simultaneous outstanding requests which should be enough for
most applications. Large volume applications would need to use a
different scheme.]
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The service sends the following response to the client:
HTTP/1.1 281 Pin code required
Content-Length: 511
Date: Mon, 19 May 2014 17:17:43 GMT
Server: Microsoft-HTTPAPI/2.0
{
"OpenPINResponse": {
"Status": 281,
"StatusDescription": "Pin code required",
"Challenge": "
o9UKSBtH1MjO7SzYwtKIIw",
"ChallengeResponse": "
C35fTms7ps80RbS1hwSt7XgqRJlkttukb-frruN_hvw",
"Cryptographic": {
"Secret": "
p8eVWYPS0YrOVr0dILrcTg",
"Encryption": "A128CBC",
"Authentication": "HS256",
"Ticket": "
9EccpNHXKaU9wfmMsktFai9K_RC-4VGbiKgvAQWDaRzIjgw7SYa5NDxSpVUomkNv
auCbw8wc_EdZ-Rsc6mwDXrkpl-9GevKpywNYkgReNgz4PgSJWnVh9h-lPhFBd_0h
l8f1CuZ9FakXpeD5QCp8Eg"}}}
To complete the transaction, the client sends a TicketRequest message
to the service containing a response to the PIN challenge sent by the
service (ChallengeResponse).
The TicketRequest message is authenticated using HTTP Session
authentication under the shared secret specified in the OpenResponse
message:
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POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Session: Value=oNHs-K49eAGTa6JFgAP0_fBiV3OPIHah4eqoMYGkIeo;
Id=9EccpNHXKaU9wfmMsktFai9K_RC-4VGbiKgvAQWDaRzIjgw7SYa5NDxSpVUo
mkNvauCbw8wc_EdZ-Rsc6mwDXrkpl-9GevKpywNYkgReNgz4PgSJWnVh9h-lPhF
Bd_0hl8f1CuZ9FakXpeD5QCp8Eg
Host: localhost:8080
Content-Length: 153
Expect: 100-continue
{
"TicketRequest": {
"Service": ["sxs-confirm-user",
"omni-query"],
"ChallengeResponse": "
2s-hdGucN7DBgYsSlbP3YCt9XfNAJxmeiaFgU8zxprk"}}
The service checks the value of ChallengeResponse against the known
PIN and if the result is correct establishes parameters for the
Connection Binding for the device.
In this case the server uses the Session Id parameter to encode
permissions associated with the request as described in [Appendix
TBS]. Accordingly the server must replace the Session Id whenever the
associated permissions change. Accordingly, the server replaces the
cryptographic parameters specified in the OpenResponse request for
use in future SXS service requests. In this case the server returns
three connections, each offering a different transport protocol
option. Each connection specifies its own set of cryptographic
parameters (or will when the code is written for that).
The service also returns a service connection the malware protection
service the client requested access to. This service connection
specifies three different service instances. Each service instance
has its own set of cryptographic parameters for use with HTTP session
authentication. In this case the three different service instances
offer different means of accessing the same service: as a JSON Web
Service over HTTP, using a binary encoding over a UDP transport and
tunnelling via DNS.
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HTTP/1.1 OK Success
Content-Length: 1762
Date: Mon, 19 May 2014 17:17:43 GMT
Server: Microsoft-HTTPAPI/2.0
{
"TicketResponse": {
"Status": 200,
"StatusDescription": "Success",
"Cryptographic": [{
"Protocol": "sxs-connect",
"Secret": "
emwwtk9hgo--u6tE-mJ-uA",
"Encryption": "A128CBC",
"Authentication": "HS256",
"Ticket": "
On8L9OSNh1q4o2fMgSmahY3AYMwHY7cdt4jdp8bT9p1iAqgk18MXj3U_NdtrUxWG
nDyPfh2px3ZqTkjzPiiunzjOl-ye3mAmKTxGzXOgOvg"}],
"Service": [{
"Service": "sxs-confirm-user",
"Name": "localhost",
"Port": 8080,
"Priority": 100,
"Weight": 100,
"Transport": "HTTP",
"Cryptographic": {
"Secret": "
2tFPA7RVgbcAv7WZC0hl0w",
"Encryption": "A128CBC",
"Authentication": "HS256T128",
"Ticket": "
o7znkpTHfrqcwsI1eHkPghCj7YsGUCp0KV2DcV1qXGlCt9wzmr2T6UcO_0YIAcEq
VdTsqRsYBtVNGs9SJyTCnMvjIlU1xQ9ZzoUtqtJsT4A"}},
{
"Service": "omni-query",
"Name": "localhost",
"Port": 8080,
"Priority": 100,
"Weight": 100,
"Transport": "HTTP",
"Cryptographic": {
"Secret": "
GCBBcZPMs8Bz_c7Yb-F06Q",
"Encryption": "A128CBC",
"Authentication": "HS256T128",
"Ticket": "
ce2u2PZ3X1izYpCNUl3zrq-LBcRBiSdOfRSknOm33854OMnRKIZTWtbpiZIBvbmW
A23FlzDxp60SB18FTgbmh5ejJKxz9xVYvnmCUm8KhY0"}},
{
"Service": "omni-query",
"Name": "localhost",
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"Port": 9090,
"Priority": 100,
"Weight": 100,
"Transport": "UDP",
"Cryptographic": {
"Secret": "
eBt0w7YrK7tdCLAALLO3pg",
"Encryption": "A128CBC",
"Authentication": "HS256T128",
"Ticket": "
TDVD0DeoWdlU-RIWB0I5BV8Xgp3L5TZD8uqQP6v9PJwdIG6DQufqLsKjhu1wtV2p
jF8R37P9MJfhBWK-g4Yb4p7U3kBrUYgScOIxNbx31gQ"}}]}}
3.2. Unbinding
After a year of use, Alice decides to replace the laptop with a new
one. Before selling the old laptop on EBay, she tells the Web Service
client to cancel the connection to the Web Service Provider.
The client sends the following mesasage to the provider:
POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Session: Value=RplcOyyQc_E4PcbNmL1vpt9xLOIdAXHNxqeBD_RHaJY;
Id=9EccpNHXKaU9wfmMsktFai9K_RC-4VGbiKgvAQWDaRzIjgw7SYa5NDxSpVUo
mkNvauCbw8wc_EdZ-Rsc6mwDXrkpl-9GevKpywNYkgReNgz4PgSJWnVh9h-lPhF
Bd_0hl8f1CuZ9FakXpeD5QCp8Eg
Host: localhost:8080
Content-Length: 24
Expect: 100-continue
{
"UnbindRequest": {}}
The Session ID specifies the connection binding. Since the Unbind
Request is only valid for that connection binding, there is no need
to specify the connection binding further in the request.
The server verifies that the request was authenticated and returns a
successful response:
HTTP/1.1 OK Success
Content-Length: 79
Date: Mon, 19 May 2014 17:17:43 GMT
Server: Microsoft-HTTPAPI/2.0
{
"UnbindResponse": {
"Status": 200,
"StatusDescription": "Success"}}
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3.3. Out of Band Completion
Alice purchases an Internet enabled coffee pot. The installer
configures the coffee pot in her kitchen but does not have access to
Alice's SXS account or a PIN code to configure it.
The installer configures the coffee pot to use the SXS account
specified by Alice. The coffee pot does not have a pssscode to enter
but does have a link to an image of the coffee pot.
The client sends the following request:
POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Host: localhost:8080
Content-Length: 224
Expect: 100-continue
{
"BindRequest": {
"Service": ["coffee-pot-control"],
"Encryption": ["A128CBC",
"A256CBC",
"A128GCM",
"A256GCM"],
"Authentication": ["HS256",
"HS384",
"HS512",
"HS256T128"]}}
Since the client does not have a PIN code, there is no need to return
a challenge. Instead the service returns the status "OOB" to indicate
that the transaction will be completed out of band.
HTTP/1.1 282 Transaction Incomplete
Content-Length: 162
Date: Mon, 19 May 2014 17:17:43 GMT
Server: Microsoft-HTTPAPI/2.0
{
"TicketResponse": {
"Status": 282,
"StatusDescription": "Transaction Incomplete",
"TransactionID": "
psqoiqY_7mPWIZM3uqDm2g",
"MinRetry": 10}}
By default the coffee pot attempts to complete the SXS connection at
ten second intervals for the first ten minutes, every thirty seconds
for the next hour, every five minutes for the following 24 hours and
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once an hour thereafter.
The client sends the following request to check the status of the
request:
POST /.well-known/sxs-connect/ HTTP/1.1
Content-Type: application/json;charset=UTF-8
Cache-Control: no-store
Host: localhost:8080
Content-Length: 22
Expect: 100-continue
{
"PollRequest": {}}
The first service response tells the coffee pot not to ask again
until five minutes have elapsed:
HTTP/1.1 282 Transaction Incomplete
Content-Length: 162
Date: Mon, 19 May 2014 17:17:43 GMT
Server: Microsoft-HTTPAPI/2.0
{
"TicketResponse": {
"Status": 282,
"StatusDescription": "Transaction Incomplete",
"TransactionID": "
Gup4C1t8v7MKvUwsmT-ffA",
"MinRetry": 10}}
The installer calls Alice to tell her that the coffee pot is ready to
connect. Alice authorizes the connection remotely via the Web Service
Provider's Web site. Alice identifies the request to connect the
coffee pot by means of the image provided. She can also use the same
image to help determine which connection to cancel when the coffee
pot is replaced.
The next time the coffee pot requests a status update, the service
responds with the connection binding parameters:
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HTTP/1.1 282 Transaction Incomplete
Content-Length: 162
Date: Mon, 19 May 2014 17:17:44 GMT
Server: Microsoft-HTTPAPI/2.0
{
"TicketResponse": {
"Status": 282,
"StatusDescription": "Transaction Incomplete",
"TransactionID": "
blwpd6lDr7_a9tDviLvmGA",
"MinRetry": 10}}
3.3.1. Message: Message
3.3.2. Message: Response
Status :
Integer [0..1] Application layer server status code
StatusDescription :
String [0..1] Describes the status code (ignored by processors)
3.3.3. Message: ConnectionRequest
3.3.4. Structure: Cryptographic
Parameters describing a cryptographic context.
Protocol :
Label [0..1] OBP tickets MAY be restricted to use with either
the management protocol (Management) or the query protocol
(Query). If so a service would typically specify a ticket with
a long expiry time or no expiry for use with the management
protocol and a separate ticket for use with the query protocol.
Secret :
Binary [1..1] Shared secret
Encryption :
Label [1..1] Encryption Algorithm selected
Authentication :
Label [1..1] Authentication Algorithm selected
Ticket :
Binary [1..1] Opaque ticket issued by the server that
identifies the cryptographic parameters for encryption and
authentication of the message payload.
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Expires :
DateTime [0..1] Date and time at which the context will expire
3.3.5. Structure: ImageLink
Algorithm :
Label [0..1] Image encoding algorithm (e.g. JPG, PNG)
Image :
Binary [0..1] Image data as specified by algorithm
3.3.6. Structure: Connection
Contains information describing a network connection.
Service :
Label [0..1] The service identifier
Name :
Name [0..1] DNS Name. Since one of the functions of an OBP
service is name resolution, a DNS name is only used to
establish a connection if connection by means of the IP address
fails.
Port :
Integer [0..1] TCP or UDP port number.
Address :
String [0..1] IPv4 (32 bit) or IPv6 (128 bit) service address
Priority :
Integer [0..1] Service priority. Services with lower priority
numbers SHOULD be attempted before those with higher numbers.
Weight :
Integer [0..1] Weight to be used to select between services of
equal priority.
Transport :
Label [0..1] OBP Transport binding to be used valid values are
HTTP, DNS and UDP.
Expires :
DateTime [0..1] Date and time at which the specified connection
context will expire.
Cryptographic :
Cryptographic [0..1] Cryptographic Parameters.
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4. OBPConnection
4.1. Bind
4.1.1. Message: BindRequest
The following parameters MAY occur in either a StartRequest or
TicketRequest:
Service :
Label [0..Many] The service identifier for the protocol for
which a connection is being established.
Encryption :
Label [0..Many] Encryption Algorithm that the client accepts. A
Client MAY offer multiple algorithms. If no algorithms are
specified then support for the mandatory to implement algorithm
is assumed. Otherwise mandatory to implement algorithms MUST be
specified explicitly.
Authentication :
Label [0..Many] Authentication Algorithm that the client
accepts. If no algorithms are specified then support for the
mandatory to implement algorithm is assumed. Otherwise
mandatory to implement algorithms MUST be specified explicitly.
4.2. BindPIN
Binding a device with mutual authentication is a two step protocol
that begins with the OpenPINRequest followed by the Ticket Request.
4.2.1. Message: OpenPINRequest
The OpenRequest Message is used to begin a device binding
transaction. Depending on the authentication requirements of the
service the transaction may be completed in a single query or require
a further Ticket Query to complete.
If authentication is required, the mechanism to be used depends on
the capabilities of the device, the requirements of the broker and
the existing relationship between the user and the broker.
If the device supports some means of data entry, authentication MAY
be achieved by entering a passcode previously delivered out of band
into the device.
The OpenRequest specifies the properties of the service (Account,
Domain) and Device (ID, URI, Name) that will remain constant
throughout the period that the device binding is active and
parameters to be used for the mutual authentication protocol.
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Account :
String [0..1] Account name of the user at the OBP service
Service :
Label [0..Many] The service identifier for the protocol for
which a connection is being established.
Domain :
Name [0..1] Domain name of the OBP broker service
HavePasscode :
Boolean [0..1] Default =False If 'true', the user has entered a
passcode value for use with passcode authentication.
HaveDisplay :
Boolean [0..1] Default =False Specifies if the device is
capable of displaying information to the user or not.
Challenge :
Binary [0..1] Client challenge value to be used in
authentication challenge mechanism as described in section
[ChallengeResponse]
DeviceID :
URI [0..1] Device identifier unique for a particular instance
of a device such as a MAC or EUI-64 address expressed as a URI
DeviceURI :
URI [0..1] Device identifier specifying the type of device,
e.g. an xPhone.
DeviceImage :
ImageLink [0..1] An image identifying the physical appearance
of the device.
DeviceName :
String [0..1] Descriptive name for the device that would
distinguish it from other similar devices, e.g. 'Alice's
xPhone".
4.2.2. Message: OpenPINResponse
An Open request MAY be accepted immediately or be held pending
completion of an inband or out-of-band authentication process.
The OpenResponse returns a ticket and a set of cryptographic
connection parameters in either case. If the
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Challenge :
Binary [0..1] Challenge value to be used by the client to
respond to the server authentication challenge.
ChallengeResponse :
Binary [0..1] Server response to authentication challenge by
the client as described in section
Cryptographic :
Cryptographic [0..1] Cryptographic Parameters.
VerificationImage :
ImageLink [0..Many] Link to an image to be used in an image
verification mechanism.
4.3. Poll
4.3.1. Message: PollRequest
The TicketRequest message is used to complete a binding request that
returned an incomplete status (350 code)
TransactionID :
Binary [0..1] Opaque transaction identifier returned when
transaction could not complete
4.4. Ticket
4.4.1. Message: TicketRequest
The TicketRequest message is used to (1) complete a binding request
begun with an PINRequest and (2) to refresh ticket or connection
parameters as necessary.
Service :
Label [0..Many] The service identifier for the protocol for
which a connection is being established.
ChallengeResponse :
Binary [0..1] The response to a serer authentication challenge
as described in section
4.4.2. Message: TicketResponse
The TicketResponse message returns cryptographic and/or connection
context information to a client.
Cryptographic :
Cryptographic [0..Many] Cryptographic Parameters.
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Service :
Connection [0..Many] A Connection describing an OBP service
point
TransactionID :
Binary [0..1] Opaque transaction identifier returned when
transaction could not complete.
MinRetry :
Integer [0..1] Minimum time to elapse before a status polling
request will be responded to.
4.5. Unbind
Requests that a previous device association be deleted.
4.5.1. Message: UnbindRequest
Since the ticket identifies the binding to be deleted, the only thing
that the unbind message need specify is that the device wishes to
cancel the binding.
4.5.2. Message: UnbindResponse
Reports on the success of the unbinding operation.
If the server reports success, the client SHOULD delete the ticket
and all information relating to the binding.
A service MAY continue to accept a ticket after an unbind request has
been granted but MUST NOT accept such a ticket for a bind request.
5. Mutual Authentication
A Connection Service MAY require that a connection request be
authenticated. Two authentication mechanisms are defined.
PIN Code
The client and server demonstrate mutual knowledge of a PIN
code previously exchanged out of band.
Out of Band Confirmation
The request for access is confirmed out of band.
In addition, services MAY accept the use of any message or transport
layer authentication scheme. For example HTTP Session Continuation or
Transport Layer Security with client authentication.
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5.1. PIN Authentication
PIN code authentication provides users with a simple and often
familiar mechanism for authenticating the connection request. The
means by which the user obtains the PIN code is outside the scope of
this document. Possible methods for distributing the PIN code include
obtaining the code from an account management Web site provided by
the Web Service Provider, letter post, email and in person.
Although the PIN value is never exposed on the wire in any form, the
protcol considers the PIN value to be text encoded in UTF8 encoding.
To encourage readability, the use of space (0x20) and hyphen (0x2D)
characters to arrange PIN characters into groups of four to seven
characters is encouraged. To avoid the risk of this practice
introducing user error, space and hyphen characters are ignored when
processing the PIN value.
Support for the full UNICODE character set in PIN codes is intended
to facilitate provision of PIN codes in the user's native language.
Web Service Providers MAY make use of any UNICODE characters they
choose but capricious choices are likely to cause users difficulty.
For example a PIN code MAY contain the ZAPF Dingbats thick tick mark
(U+2704) but users would almost certainly find it difficult to enter
and may confuse it with the similar thin tick mark (U+2703).
Servers that support PIN Authorization SHOULD offer the choice of a
PIN that only uses numeric digits ('0', '1', '2', '3', '4', '5', '6',
'7', '8', '9'). Clients that support PIN Authorization MUST allow
entry of PINS that only contain numeric digits.
The PIN Mechanism is a three step process:
The client sends an OpenRequest message to the Service containing a
challenge value CC.
The service returns an OpenResponse message containing to the client a
server challenge value SV and a server response value SR.
The client sends a TicketRequest message to the service containing a
client response value CR.
Since no prior authentication key has been established the
OpenRequest and OpenResponse messages are sent without message
authentication.
The Challenge values CC, and SC are cryptographic nonces. The nonces
SHOULD be generated using an appropriate cryptographic random source.
The nonces MUST be at least as long as 128 bits, MUST be at least the
minimum key size of the authentication algorithm used and MUST NOT
more than 640 bits in length (640 bits should be enough for anybody).
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The server response and client response values are generated using an
authentication algorithm selected by the server from the choices
proposed by the client in the OpenRequest message.
The algorithn chosen may be a MAC algorithm or an encrypt-with-
authentication (EWA) algorithm. If an EWA is specified, the encrypted
data is discarded and only the authentication value is used in its
place.
Let A(d,k) be the authentication value obtained by applying the
authentication algorithm with key k to data d.
To create the Server Response value, the UTF8 encoding of the PIN
value 'P' is first pre-processed to remove space and hyphen
characters, then converted into a symmetric key KPC by using the
Client challenge value as the key truncating if necessary and then
applied to the of the OpenRequest message:
[
KPC = A (PIN, CC)
SR = A (Secret + OpenRequest, KPC)
In the Web Service Binding, the Payload of the message is the HTTP
Body as presented on the wire. The Secret and Server Challenge are
presented in their binary format and the '+' operator stands for
simple concatenation of the binary sequences.
This protocol construction ensures that the party constructing SR:
Knows the PIN code value (through the construction of KPC). Is
responding to the Open Request Message (SR depends on OpenRequest).
Has knowlege of the secret key which MUST be used to authenticate the
following TicketRequest/TicketResponse interaction that will
establish the actual connection. Does not provide an oracle the PIN
value. That is, the protocol does not provide a service that reveals
the (since the value SR includes the value SC which is a random nonce
generated by the server and cannot be predicted by the client).
To create the Client Response value, secret key is applied to the PIN
value and server Challenge:
CR = A (PIN + SC + OpenResponse, Secret)
Note that the server can calculate the value of the Client Response
token at the time that it generates the Server Challenge. This
minimizes the amount of state that needs to be carried from one
request to the next in the Ticket value when using the stateless
server implementation described in section
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This protocol construction ensures that the generator of CR
Knows the PIN value. Is respoding to the OpenResponse generated by
the server.
Note that while disclosure of an oracle for the PIN value is a
concern in the construction of CR, this is not the case in the
construction of SR since the client has already demonstrated
knowledge of the PIN value.
5.1.1. Example: Latin PIN Code
The Connection Request example of section demonstrates the use of an
alphanumeric PIN code using the Latin alphabet.
The PIN code is [[Q80370-1RA606-F04B] and the authentication
algorithm is [[HS256]. The value KPC is calculated thus:
PIN: 51 38 30 33 37 30 2d 31 52 41 36 30 36 2d 46 30 34 42
Client Challenge: 04 e7 a7 fe 41 33 7b 74 c9 8b b9 d6 eb 33 bb dc
KPC: 10 c9 32 db 58 77 16 d6 cb 07 21 d9 36 b0 1c dd 25 9e af 75 ba
28 24 96 38 67 ac 7c 7f dd 6f 38
For the sake of example, we take the OpenRequest message payload to
be {...}. The data over which the hash value is calulated is Secret +
OpenRequest:
Secret: a7 c7 95 59 83 d2 d1 8a ce 56 bd 1d 20 ba dc 4e
Request Payload: 7b 2e 2e 2e 7d
Server Response: fe fc 5b 76 4a d4 e2 e5 bc 17 02 3f a9 58 15 92 cd
1e 7d ae c5 a1 c4 cb 71 d8 ea 94 33 cd ed f2
The data for the client response is PIN + Server Challenge + Payload:
PIN: 51 38 30 33 37 30 2d 31 52 41 36 30 36 2d 46 30 34 42
Server Challenge: a3 d5 0a 48 1b 47 d4 c8 ce ed 2c d8 c2 d2 88 23
Request Payload: 7b 2e 2e 2e 7d
Applying the key Secret to the data produces the client response:
Client Response: 0a 48 14 35 3a bd 5c fb 55 5f 05 24 0b 94 a0 a0 a0
1c 00 07 d4 ea 6c 1f 2a 50 b2 25 a7 7c ef bd
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5.1.2. Example: Cyrillic PIN Code
If the PIN code in the earlier example was 'parol1' (the Russian for
'password1') in Cyrilic script the value KP would be calculated as
follows
PIN: d0 bf d0 b0 d1 80 d0 be d0 bb d1 8c 31
KPC: 10 c9 32 db 58 77 16 d6 cb 07 21 d9 36 b0 1c dd 25 9e af 75 ba
28 24 96 38 67 ac 7c 7f dd 6f 38
The rest of the protocol would then continue as before.
5.2. Out of Band Confirmation
The Out Of Band Confirmation mechanism is a three step process in
which:
* The client makes an OpenRequest message to the service and
obtains an OpenResponse message.
* The connection binding is authorized through an out of band
process.
* The client makes a TicketRequest to the service and obtains a
TicketResponse message to complete the exchange.
Since no prior authentication key has been established the
OpenRequest and OpenResponse messages are sent without
authentication.
The principal concern in the Out Of Band Confirmation mechanism is
ensuring that the party authorizing the request is able to identify
which party originated the request they are attempting to identify.
If a device has the ability to display an image it MAY set the
HasDisplay=true in the OpenRequest message. If the broker recieves an
OpenRequest with the HasDisplay value set to true, the OpenResponse
MAY contain one or more VerificationImage entries specifying image
data that is to be displayed to the user by both the client and the
confirmation interface.
Before confirming the request, the user SHOULD verify that the two
images are the same and reject the request in the case that they are
not.
Many devices do not have a display capability, in particular an
embedded device such as a network switch or a thermostat. In this
case the device MAY be identified by means of the information
provided in DeviceID, DeviceURI, DeviceImage and DeviceName.
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6. Protocol Binding
A single protocol binding is defined:
* JSON encoding is used to express SXS messages.
* A HTTP session layer with HTTP session continuation is used for
message authentication.
* TLS transport is required for confidentiality and service
authentication.
Implementations MAY support use of alternative encodings, session
layers or transports provided that the necessary confidentiality and
authentication criteria described below are met. The means by which
negotiation of the use of such encodings is achieved is outside the
scop of this document.
6.1. JSON encoding
Messages are expressed in JSON encoding [RFC4627].
Protocol schema types are mapped to JSON encoding as follows:
Integer
Data of type Integer is encoded using the JSON number encoding.
Name
Data of type Name is encoded using the JSON string encoding.
String
Data of type String is encoded using the JSON string encoding.
Binary
Data of type Binary is converted to strings using the Base64url
encoding specified in [!RFC4648] /> and encoded using the JSON
string type.
DateTime
Data of type DateTime is converted to string using the UTC time
conversion specified in [!RFC3339] /> with a UTC offset of
00:00.
6.1.1. HTTP Session Layer
Messages are presented over a HTTP session layer [RFC2616]. The use
of HTTP as a session layer permits multiple Web Services on the same
host to share the same DNS name, IP address and port number and
enables use of HTTP Session Continuation [I-D.hallambaker-
httpsession] for message authentication.
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Use of HTTP Session Continuation mechanism allows message
authentication data to be presented in the HTTP message header rather
than the message content provides a clean separation of the message
authentication data from the data being authenticated. The scope of
the authentication data is simply the message content after transport
encoding (e.g. chunked) has been removed.
The use of HTTP session continuation is necessary to achieve mutual
authentication even though TLS transport is required.
Only the HTTP Session header is used. The negotiation of the Session
parameters is performed within SXS.
[TO-DO: Specify TLS binding options?]
[TO-DO: Switch back from using JOSE algorithm names to HTTP Session
algorithm names]
6.1.2. TLS transport
TLS transport [RFC4627] is used
Support for the PKIX logotype extension [RFC3709] is highly
recommended
Use of an enhanced assurance certificate (e.g. CABForum EV) is likely
to be required in most applications and is strongly recommended if
Lotypes are used.
7. Service Identification and Discovery
The prefix '[PREFIX-TBD]' has been registered for use as a protocol
identifier for SXS in the URI, SRV and Well Known Location
registries.
The URI form identifying a SXS account identifier is:
PREFIX-TBD:<service>:<account>:< or PREFIX-
TBD:<service>:<account>:<:subaccount>
Where <service> is the DNS name of the Web Service Provider,
<account> is the name of the account at the service provider and
<subaccount> is an optional sub-account specifier.
Use of the URI form is only needed in cases where the purpose of the
identifier is not clear from the context, in a HTML anchor for
example. A SXS client requesting entry of the service account
identifier MUST support entry of the short form identifier:
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<account>@<service> or <:subaccount>/<account>@<service>
DNS Service (SRV) record discovery is the preferred method of host
discovery as this provides for fault tollerance and load balancing.
SXS clients SHOULD support use of DNS SRV records for host discovery
and MUST support use of DNS A/AAAA records for host discovery.
A compliant SXS service MUST be offered at the .well-known location
/.well-known/PREFIX-TBD. Use of SXS protocol at other service
locations is permissible for testing and protocol development
purposes but such configurations are not compliant and clients are
not required to support them. The URL for the SXS service is
therefore:
https://<service>/.well-known/PREFIX-TBD
8. UDP Binding (UYFM)
The UDP Binding (UYFM) allows a transaction to be transmitted as a
single UDP packet request followed by up to 16 UDP response packets.
The message encapsulation is described using the format desribed in
[RFC5246]. Note that in this notation the size of a length specifier
is defined by the maximum number of octets permitted in the
corresponding data field. For convenience these sizes are given as
255 or 65335 to specify 1 and 2 byte length specifiers respectively.
The actual length of the data fields that can be used in practice
will depend on the maximum size of UDP packet that can be reliably
transmitted.
opaque TransactionID<16..255>
opaque SecurityContextID<1..255>
8.1. Request
If the UDP transport is in use, a request consists of exactly one
packet.
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A request has the following structure:
struct {
TransactionID transactionID;
SecurityContextID securityContextID;
opaque encryptedPayload<1..65535>
opaque authenticationCode<1..255>
} Request;
Where:
transactionID
Is a unquie identifier for the transaction and an input to the
function used to derrive the initialization vector (IV) for the
encryption algorithm
securityContextID
Is the opaque security context identifier returned by the
Service Connect Service.
encryptedPayload
Is the encrypted message payload.
8.2. Response
A response MAY consist of 1 or up to 16 packets, each formatted as
follows:
struct {
TransactionID transactionID;
uint8 index;
uint8 maxIndex;
uint16 clearResponse;
opaque encryptedPayloadSegment<0..65535>
opaque authenticationCode<1..255>
} Response;
Where:
transactionID
Is a unquie identifier for the transaction and an input to the
function used to derrive the initialization vector (IV) for the
encryption algorithm
index
Is the index number of this response packet.
maxIndex
Is the index number of the last packet. The value of maxIndex
MUST be the same for every packet. Receivers MUST reject
packets
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clearResponse
Is a response code sent enclair. The value 0 indicates a
successful response. Error codes TBS. It might be expedient to
merge these with index and maxIndex to shave some bytes.
encryptedPayloadSegment
Is the encrypted message payload segment.
To obtain the encryptedPayload of the response, the receiver:
* Waits for all the response packets to arrive
* Sorts the response packets by the value of index.
* Extracts the value of encryptedPayloadSegment from each
response
* Concatenate the values of encryptedPayloadSegment to obtain the
encryptedPayload value
UDP packets MAY be sent out of order and the order in which they were
received MAY not match the order in which they were sent. A receiver
MUST accept response packets recieved in any order.
8.3. Payload
The payload is a sequence of the following types of data:
JSONData
Payload data in JSON encoding
JSONCData
Payload data in JSON-C encoding as described in [!I-
D.hallambaker-jsonbcd]
DNSMessageEntry
A DNS Message as specified in [RFC1035]
PaddingEntry
The Payload MAY contain padding.
LastMAC
MAC value from the previous message in the transaction.
SecurityContextIDEntry
A replacement security context identifier.
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KeyEntry
A secret key for use with the immediately preceeding
SecurityContextID.
Future use
The Payload may contain additional options (To be defined)
The payload data is encoded according to the following schema:
enum {PaddingEntry (0), SecurityContextIDEntry (2),
KeyEntry (3), LastMac (4), JSONData (16), JSONCData (17),
DNSMessageEntry (18), (255)} PayloadEntryType;
struct {
PayloadEntryType entryType;
opaque data<0..65535>
} Response;
The SecurityContextIDEntry and KeyEntry data types are used by the
server to issue a new security context and key to the client.
Changing the security context identifier prevents linkage of
transactions across network configurations.
One consequence of putting the LastMAC value inside the Payload data
is that this provides an attacker with a sequence of known plaintext
and ciphertext.
9. Acknowledgements
Rob Stradling, Robin Alden...
10. Security Considerations
10.1. Denial of Service
10.2. Breach of Trust
10.3. Coercion
11. IANA Considerations
[TBS list out all the code points that require an IANA registration]
12. Stateless server
The protocol is designed to permit but not require the server to
store connection binding state in the Session ID of the HTTP Session
Continuation authentication mechanism.
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The Session IDs are opaque as far as the client is concerned. The
client receives the Session ID from the service and returns it with
each request. The internal structure of the Session ID is therefore
outside the scope of this specification but is provided here to
assist implementers.
In the PIN Authentication example, two SessionIDs are issued by the
server:
* A temporary ID in response to the initial client OpenRequest.
* A connection binding ID when the client PIN confirmation is
accepted and the connection binding is created.
Both tickets have the same common wrapper structure:
IV + Encrypt ( Ticket + Mac ( Ticket, Key) Key)
Where:
IV
The Initialization vector for the encryption scheme
Encrypt
The Encryption algorithm (AES in CBC Mode)
Ticket
The ticket data
MAC
The Message Authentication algorithm (HMAC-SHA2-256)
12.1. Temporary ID
The temporary ticket returned in the OpenRequest example above is
represented in Base64URL encoding as follows:
9EccpNHXKaU9wfmMsktFai9K_RC-4VGbiKgvAQWDaRzIjgw7SYa5NDxSpVUomkNv
auCbw8wc_EdZ-Rsc6mwDXrkpl-9GevKpywNYkgReNgz4PgSJWnVh9h-lPhFBd_0h
l8f1CuZ9FakXpeD5QCp8Eg
The format of the ticket is 16
IV: f4 47 1c a4 d1 d7 29 a5 3d c1 f9 8c b2 4b 45 6a
Encrypted Data: 2f 4a fd 10 be e1 51 9b 88 a8 2f 01 05 83 69 1c c8 8e
0c 3b 49 86 b9 34 3c 52 a5 55 28 9a 43 6f 6a e0 9b c3 cc 1c fc 47 59
f9 1b 1c ea 6c 03 5e b9 29 97 ef 46 7a f2 a9 cb 03 58 92 04 5e 36 0c
f8 3e 04 89 5a 75 61 f6 1f a5 3e 11 41 77 fd 21 97 c7 f5 0a e6 7d 15
a9 17 a5 e0 f9 40 2a 7c 12
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The encrypted data is decrypted under the master key of the server.
In this example the server has a single fixed key that does not
change over time. There should really be a key index prefixing it to
identify the key number.
The Master Key is: 55 e1 0a 1a 8e 68 8a bd 5a 15 d8 cb b2 63 38 ef 9d
3d 78 bf 62 62 f9 eb 52 ed af ee a5 55 67 0d
The decrypted data contains the algorithm identifiers, shared secret
and message authentication code:
Version Number: 00
Key Identifier: 01
Authentication Algorithm: 00
Encryption Algorithm: 00
Key Data: a7 c7 95 59 83 d2 d1 8a ce 56 bd 1d 20 ba dc 4e
User Name Length: 11
User Name: 61 6c 69 63 65 40 65 78 61 6d 70 6c 65 2e 63 6f 6d
Client Challenge Length: 10
Client Challenge: 04 e7 a7 fe 41 33 7b 74 c9 8b b9 d6 eb 33 bb dc
Server Challenge Length: 10
Server Challenge: a3 d5 0a 48 1b 47 d4 c8 ce ed 2c d8 c2 d2 88 23
Message Authentication Code: aa e3 19 72 c3 bc 6c 1f 48 35 0f 47 5a
3a 78 5e 34 b1 9e 92 32 42 10 a0 b2 d7 90 94 e6 8c 82 7e
12.2. Connection Binding ID
The format of the Connection binding ticket is similar to that of the
Temporary ticket except that it does not contain the Client or Server
challenge nonces.
IV: 3a 7f 0b f4 e4 8d 87 5a b8 a3 67 cc 81 29 9a 85
Encrypted Data: 8d c0 60 cc 07 63 b7 1d b7 88 dd a7 c6 d3 f6 9d 62 02
a8 24 d7 c3 17 8f 75 3f 35 db 6b 53 15 86 9c 3c 8f 7e 1d a9 c7 76 6a
4e 48 f3 3e 28 ae 9f 38 ce 97 ec 9e de 60 26 29 3c 46 cd 73 a0 3a f8
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Internet-Draft Service Connection Service (SXS) May 2014
The decrypted data is:
Version Number: 00
Key Identifier: 00
Authentication Algorithm: 00
Encryption Algorithm: 00
Key Data: 7a 6c 30 b6 4f 61 82 8f be bb ab 44 fa 62 7e b8
User Name Length: 0c
User Name: 65 40 65 78 61 6d 70 6c 65 2e 63 40
Message Authentication Code: 90 c2 4b 03 17 47 31 19 60 85 96 23 8f
4b 9c 53 b6 1a b2 9a 75 01 3a 76 19 38 11 63 66 f3 b8 7b
13. References
13.1. Normative References
[RFC3339] Klyne, G.,Newman, C., "Date and Time on the Internet:
Timestamps", RFC 3339, July 2002.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, October 2006.
[RFC3709] Santesson, S.,Housley, R.,Freeman, T., "Internet X.509
Public Key Infrastructure: Logotypes in X.509
Certificates", RFC 3709, February 2004.
[I-D.hallambaker-jsonbcd] Hallam-Baker, P, "Binary Encodings for
JavaScript Object Notation: JSON-B, JSON-C, JSON-D",
Internet-Draft draft-hallambaker-jsonbcd-01, 21 January
2014.
[RFC5246] Dierks, T.,Rescorla, E., "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627, July 2006.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2616] Fielding, R.,Gettys, J.,Mogul, J.,Frystyk, H.,Masinter,
L.,Leach, P.,Berners-Lee, T., "Hypertext Transfer Protocol
-- HTTP/1.1", RFC 2616, June 1999.
Hallam-Baker November 20, 2014 [Page 35]
Internet-Draft Service Connection Service (SXS) May 2014
[I-D.hallambaker-privatedns] Hallam-Baker, P, "Private-DNS",
Internet-Draft draft-hallambaker-privatedns-00, 9 May
2014.
[I-D.hallambaker-httpsession] Hallam-Baker, P, "HTTP Session
Management", Internet-Draft draft-hallambaker-httpsession-
02, 21 January 2014.
Author's Address
Phillip Hallam-Baker
Comodo Group Inc.
philliph@comodo.com
Hallam-Baker November 20, 2014 [Page 36]
