TM-RID Authentication Formats
draft-wiethuechter-tmrid-auth-00
This document is an Internet-Draft (I-D).
Anyone may submit an I-D to the IETF.
This I-D is not endorsed by the IETF and has no formal standing in the
IETF standards process.
The information below is for an old version of the document.
| Document | Type |
This is an older version of an Internet-Draft whose latest revision state is "Replaced".
|
|
|---|---|---|---|
| Authors | Adam Wiethuechter , Stuart W. Card , Robert Moskowitz | ||
| Last updated | 2019-10-18 | ||
| Replaced by | draft-wiethuechter-drip-auth | ||
| RFC stream | (None) | ||
| Formats | |||
| Stream | Stream state | (No stream defined) | |
| Consensus boilerplate | Unknown | ||
| RFC Editor Note | (None) | ||
| IESG | IESG state | I-D Exists | |
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-wiethuechter-tmrid-auth-00
TMRID A. Wiethuechter
Internet-Draft S. Card
Intended status: Standards Track AX Enterprize
Expires: April 20, 2020 R. Moskowitz
HTT Consulting
October 18, 2019
TM-RID Authentication Formats
draft-wiethuechter-tmrid-auth-00
Abstract
This document describes how to include HIPv2 into the proposed ASTM
Remote ID specification defined in WK65041 by the F38 Committee under
a Broadcast Remote ID (RID) scenario. It defines a few different
message schemes that can be used to assure past messages sent by a UA
and also act as a assurance for UA trustworthiness in the absence of
Internet connectivity at the receiving node.
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 April 20, 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
Wiethuechter, et al. Expires April 20, 2020 [Page 1]
Internet-Draft TM-RID Auth Formats October 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
2. Terms and Definitions . . . . . . . . . . . . . . . . . . . . 3
2.1. Requirements Terminology . . . . . . . . . . . . . . . . 3
2.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
3. UAS Problem Space . . . . . . . . . . . . . . . . . . . . . . 4
3.1. Broadcast RID . . . . . . . . . . . . . . . . . . . . . . 4
3.2. Network RID . . . . . . . . . . . . . . . . . . . . . . . 4
3.3. TM-RID Focus Problem Space . . . . . . . . . . . . . . . 5
4. Trustworthy Multi-purpose Remote ID . . . . . . . . . . . . . 5
4.1. HIP Benefits for Remote ID . . . . . . . . . . . . . . . 5
4.2. Levels of Trust . . . . . . . . . . . . . . . . . . . . . 6
4.2.1. TM-RID Level 1 (Identification) . . . . . . . . . . . 6
4.2.2. TM-RID Level 2 (Authentication) . . . . . . . . . . . 7
4.2.3. TM-RID Level 3 (Communication) . . . . . . . . . . . 8
5. ASTM Authentication Message . . . . . . . . . . . . . . . . . 8
6. HIP Based Extensions to the ASTM Authentication Message . . . 9
6.1. Signed Hash Lists . . . . . . . . . . . . . . . . . . . . 9
6.1.1. Limitations . . . . . . . . . . . . . . . . . . . . . 12
6.2. HIP Based Authentication Wrapper . . . . . . . . . . . . 13
6.2.1. Specific Use Case: Trusted Messages . . . . . . . . . 15
6.3. HIP Based Offline Authentication . . . . . . . . . . . . 15
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
8. Security Considerations . . . . . . . . . . . . . . . . . . . 17
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 17
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 17
10.1. Normative References . . . . . . . . . . . . . . . . . . 17
10.2. Informative References . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction
The technology space of Unmanned Aircraft (UA) has been expanding
rapidly on numerous fronts. This rapid expansion has been noticed by
various agencies and they are moving to add standards to protect
individuals and organizations.
The ASTM has been selected to create a specification for Remote ID
(RID) classification that various CAAs can cite. The work presented
here is an expansion upon their standards to integrate IETF methods
and work into the space where it is useful.
Wiethuechter, et al. Expires April 20, 2020 [Page 2]
Internet-Draft TM-RID Auth Formats October 2019
The current draft standard for Remote ID (RID) does not, in any
meaningful capacity, address the concerns of trust in the UA space
with communication in the Broadcast RID environment. This is a
requirement that will need to be addressed eventually for various
different parties that have a stake in the UA industry.
This document will show how UAS RID can be made trustworthy and can
enable immediate encrypted communications between mutually
authenticated parties (typically observer and pilot) by using the
Host Identity Protocol Version 2 (HIPv2) [RFC7401].
Further, by leveraging the Hierarchical HIT (HHIT)
[I-D.moskowitz-hip-hierarchical-hit] RID applications can be enabled
to have trustworthiness for UA communication in the constrained
environment of Broadcast RID.
This solution is called "Trustworthy Multi-purpose Remote ID".
2. Terms and Definitions
2.1. Requirements Terminology
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.
2.2. Definitions
CAA Civil Aeronautics Administration. An example is the Federal
Aviation Administration; (FAA) in the United States of America.
C2 Command and Control.
RID Remote ID. Maximum length of 20 bytes.
HI Host Identity.
HIT Host Identity Tag.
HHIT Hierarchical Host Identity Tag.
UA Unmanned Aircraft.
UAS (Unmanned Aircraft System) Composed of Unmanned Aircraft and all
required on-board subsystems, payload, control station, other
required off-board subsystems, any required launch and recovery
Wiethuechter, et al. Expires April 20, 2020 [Page 3]
Internet-Draft TM-RID Auth Formats October 2019
equipment, all required crew members, and command and control (C2)
links between UA and the control station.
USS (UAS Service Supplier) USSs provide UTM services to support the
UAS community, to connect Operators and other entities to enable
information flow across the USS network, and to promote shared
situational awareness among UTM participants. (From FAA UTM
ConOps V1, May 2018).
3. UAS Problem Space
UA Systems (UAS) are usually in a volatile environment when it comes
to communication. UA are generally small with little computational
(or flying) horsepower to carry standard communication equipment.
This limits the mediums of communication to few viable options. The
ASTM standard focuses on two ways of communicating to a UAS for RID:
Broadcast and Network.
3.1. Broadcast RID
Broadcast RID has three mediums of communication defined by the ASTM.
These are: Bluetooth 4.X, Bluetooth 5.X Long Range, and Wifi with
Neighbor Aware Networking (NAN).
A UA under the ASTM standard is required to support at least one of
these methods to broadcast messages using the medium's respective
advertisement framing methods. Note that when using Bluetooth 5 it
must be transmitted concurrently with Bluetooth 4.X (which the ASTM
refers to as Bluetooth Legacy).
The selection of the Broadcast medium was driven by research into
what is commonly available on 'ground' units (smartphones and
tablets) and what was found as prevalent or 'affordable' in UA.
Further, there must be an API for the UAS receiving application to
have access to these messages. It is worth noting that at this time,
Bluetooth 4.X is readily available but the other two are more for
future devices. Thus the focus on working within the 26 byte limit
of the Bluetooth 4.X "Broadcast Frame" that goes out on the beacon
channels.
Finally, the 26 byte limit of the Bluetooth 4.1 "Broadcast Frame"
strictly enforces the RID maximum length of 20 bytes.
3.2. Network RID
Network RID is a much more open space and is enabled when a UA has
Internet connectivity on board. This means, in most cases, the
Wiethuechter, et al. Expires April 20, 2020 [Page 4]
Internet-Draft TM-RID Auth Formats October 2019
inclusion of a cellular modem on board, but can include WiFi
communications. Network RID is the subject of a future document.
3.3. TM-RID Focus Problem Space
This document will focus on adding trust to Broadcast RID. The ASTM
proposed standard 'used' the limitation put onto the UA by its
physical design and radio communications to leave one important issue
un-addressed: Trust.
Further, the one-way, Adhoc, nature of Broadcast RID precludes any
stateful security protocol to provide trust which further hampered
any evaluation of Trust methodologies.
As currently defined by ASTM, any UA can announce a RID and an
observer would be seriously challenged to validate the validity in
the RID and thus any information about the UA. This is why trust in
the RID and related trust for all Broadcast messages is considered
critical in the safe operation of UAs.
4. Trustworthy Multi-purpose Remote ID
This document addresses this oversight by using HIP to bring trust
into UA communication without having to redesign the standard. The
Host Identity Tag (HIT) and Host Identity (HI) of HIP are used to
provide signed statements of Trust of the broadcast messages. HIP,
for Broadcast RID, is only used as in HHIT Registries
[I-D.moskowitz-hip-hhit-registries] to prevent duplicate HHITs and
provide the Registries with UA information for DNS and other
inquires.
The use of HIP is strongly encouraged by the authors to be used in
Network RID.
4.1. HIP Benefits for Remote ID
The Host Identity Tag (HIT) of HIP is unique among structured number
Identifiers. It significantly more valuable as an Identifier than
any other structured number in IETF standards, including [RFC6920]
option of hash of Public Keys.
It is a valid IPv6 (non-routable) address. As such it can be used
directly as addresses in applications.
The Suite ID field informs the receiver of the underlying
cryptographic Identity.
Wiethuechter, et al. Expires April 20, 2020 [Page 5]
Internet-Draft TM-RID Auth Formats October 2019
The hash of the Host Identity public key provides the real proof
of ownership of the HIT through any private key operation.
By using HIP a number of benefits to UAs are immediately enabled:
Unique Identification: Using the HIP's Host Identity Tag (HIT) a
unique identifier can be used as a handle for more information
than just PII.
Immediate UA Context: The Hierarchical Host Identity Tag (HHIT)
provides provable context about the Identity.
Automatic Connectivity: When both devices are using HIP the HIT can
be used, along with standard DNS methods, to quickly create secure
connections between hosts. This applies even when both end-points
are mobile in nature.
4.2. Levels of Trust
TM-RID for Broadcast RID there are three levels of trust:
Level 1 (Identification): The HHIT is a unique identifier that can
enable other levels of TM-RID while still fitting within the
specification of the standard for ID fields.
Level 2 (Authentication): When a HHIT is used for an ID of a UA a
lookup to other information is easy and already has infrastructure
to do so in place.
Level 3 (Communication): After looking up information using a HHIT
dynamic communication to other parties can be performed that is
secure and trusted. (Note that this is for Network RID.)
4.2.1. TM-RID Level 1 (Identification)
Level 1 uses HHIT as an ID type in the ASTM standard. This gives no
immediate effects of HIP or trust for the UA, but can enable further
features in other levels.
Under the current proposed standard (which does not include HIP as a
valid entry for ID type) the ID type of "4" should be used in the
Basic ID Message to signal the use of a HHIT as the ID.
At the time of writing Type 4 in the ASTM standard has yet to used,
there is no definition for Private used ID types in the standard to
use.
Wiethuechter, et al. Expires April 20, 2020 [Page 6]
Internet-Draft TM-RID Auth Formats October 2019
The RID ONLY is sent in the Basic ID Message. The standard relies on
the MAC address to relate all messages from a UA to this RID.
Level 1 does not provide any trust in the RID. The Basic ID Message
is limited to 24 bytes and can only carry the, at maximum 20 byte,
RID.
Below is an example of a ASTM Basic ID message format using HHIT as
the UAS ID type.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| HHIT |
| |
| |
| |
| +-----------------------------------------------|
| | RESERVED |
+---------------+-----------------------------------------------+
Msg. Header (1 byte)
Contains two subfields: ID Type and UA Type (of 4 bits each).
In the above example the ID Type would be set to "0100".
4.2.2. TM-RID Level 2 (Authentication)
With Level 2 it is assumed that the receiving application being used
by the observer has encountered a HHIT in a Basic ID Message.
A HHIT can be used to construct a FQDN that can be used in a DNS
query that will minimally provide the HI for validating signed
Broadcast Authentication Messages.
This construction may be through a reverse lookup using the HHIT as
an IPv6 address. It may be through an FQDN construction method
imposed on the receiving application by the receiving application's
USS.
A Suite ID of EdDSA [I-D.moskowitz-hip-new-crypto] with the
EdDSA25519 curve is used as its 64 byte signature will fit in the
Authentication Messages.
Wiethuechter, et al. Expires April 20, 2020 [Page 7]
Internet-Draft TM-RID Auth Formats October 2019
Besides the HI, the most common case will most likely yield a pointer
of some kind to be used in a controlled access controlled database to
obtain PII.
4.2.3. TM-RID Level 3 (Communication)
Under Level 3 the HHITs, along with Rendezvous Servers (RVS) and
other HIP aware/enabled infrastructure, would be used as intended to
connect two hosts securely.
This will be the subject of the Network RID document(s).
5. ASTM Authentication Message
The ASTM Authentication Message format is defined as follows:
Page 0:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Msg. Header | Page Count | Length | /
+---------------+---------------+---------------+---------------+
/ Timestamp | |
+-----------------------------------------------+ |
| |
| |
| |
| Authentication Data / Signature |
| |
| |
| |
+---------------------------------------------------------------+
Page 1 - 4:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| |
| Authentication Data / Signature |
| |
| |
| |
| |
Wiethuechter, et al. Expires April 20, 2020 [Page 8]
Internet-Draft TM-RID Auth Formats October 2019
+---------------------------------------------------------------+
Msg. Header
A byte field containing two 4 bit fields.
Authentication Type and Page Number.
Page Count
Only on page 0. Total number of pages this
authentication message has. Max value of 5.
Length
Total length of Authentication Data / Signature
in bytes. Value of 0 - 109.
Timestamp
32 bit Unix timestamp since 00:00:00 01/01/2019.
Authentication Data / Signature
Opaque authentication data.
A few important things to note on this format and its constraints.
1. Each page has only 24 bytes based on the Bluetooth 4.X/5.X
specification.
2. The limit on Page Count of 5 is based on being able to fit this
message as well as 5 other messages (each capped at 25 bytes)
into a Bluetooth 5 atomic message. The intention is that this
message authenticates the whole pack.
6. HIP Based Extensions to the ASTM Authentication Message
The following section describes various methods that HIP can help
enable more trustworthy communication using the Authentication
Message as the base. Each diagram will show all 5 pages of the
format filled out as examples.
6.1. Signed Hash Lists
This format is designed to provide provenance to Broadcast RID
messages sent by a give UAS.
Page 0:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Msg. Header | Page Count | Length | /
Wiethuechter, et al. Expires April 20, 2020 [Page 9]
Internet-Draft TM-RID Auth Formats October 2019
+---------------+---------------+---------------+---------------+
/ Timestamp | H-Alg | H-Len |
+---------------------------------------------------------------+
| Hash of Previous Auth. Message |
+---------------------------------------------------------------+
| Hash of Current Auth. Message |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
DataPage 1:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+-------------------------------+
| Msg. Header | H-Alg | H-Len | RESERVED |
+---------------+---------------+-------------------------------+
| Message Hash |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
| Message Hash |
+---------------------------------------------------------------+
Page 2:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+-------------------------------+
| Msg. Header | RESERVED | Signature Length |
+---------------+---------------+-------------------------------+
| Signature Algorithm | |
+-------------------------------+ |
| |
| |
| |
| HHIT Signature |
| |
| |
| |
+---------------------------------------------------------------+
Page 3:
0 1 2 3
Wiethuechter, et al. Expires April 20, 2020 [Page 10]
Internet-Draft TM-RID Auth Formats October 2019
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| |
| HHIT Signature |
| |
| |
| |
| |
+---------------------------------------------------------------+
Page 4:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| |
| HHIT Signature |
| |
| |
| |
| |
+---------------------------------------------------------------+
H-Alg, H-Len: (4 bits), (4 bits)
These are fields for relaying information of the Hash
algorithm used for the messages and the Hash length (in octets).
For this example of the format a length of 4 bytes is
used.
Hash of Previous Auth. Message: (4 bytes)
A hash of the previous send Authentication message.
Hash of Current Auth. Message: (4 bytes)
A hash of the current Authentication message.
Message Hash: (4 bytes)
A hash of a previously sent message.
Signature Length: (2 bytes)
Wiethuechter, et al. Expires April 20, 2020 [Page 11]
Internet-Draft TM-RID Auth Formats October 2019
Length of signature in octets, excluding Length, and Padding
Signature Algorithm: (2 bytes)
Self explanatory.
HHIT Signature: (64 bytes)
EdDSA25519 signature using an EdDSA25519-based HHIT from HIP.
Spread across 3 pages of a given DataPage.
This specific format has various different ways to be added into the
Authentication Message structure - the general concept is the same
regardless.
By hashing previously sent messages and signing them we gain trust in
the UAS's previous reports. An observer who has been listening for
any length of time can hash received messages and cross check against
listed hashes. The signature is signed across the list of hashes.
Two special hashes are included; a previous authentication hash,
which links to the previous signed hash list message, as well as a
current hash. This gives a pseudo-blockchain provenance to the
authentication message that could be traced back if the observer was
present for extended periods of time.
In regards to the creation and use of the current authentication hash
field:
First during creation and signing of this message format this field
MUST be set to 0. So the signature will be based on this field being
0, as well as its own hash. It is an open question of if we compute
the hash, then sign or sign then compute.
There a few different ways to cycle this message. We can "roll up"
the hash of 'current' to 'previous' when needed or to completely
recompute the hash. This mostly depends on the previous note.
6.1.1. Limitations
With the current format defined by ASTM only 7 messages can be hashed
reasonably in the above format.
Another option is to places hashes into the Authentication Wrapper
format (also defined in this document). This only gives five total
hashes - excluding the pseudo-blockchain linking hashes entirely.
To address this problem the authors feel that the Authentication
Messages needs to have a max bound of 10 pages, instead of 5. This
argument is discussed later in this document.
Wiethuechter, et al. Expires April 20, 2020 [Page 12]
Internet-Draft TM-RID Auth Formats October 2019
6.2. HIP Based Authentication Wrapper
This format is a way to authenticate a given UA using the first 2
levels of TM-RID for UAS.
Page 0:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+---------------+---------------+---------------+
| Msg. Header | Page Count | Length | /
+---------------+---------------+---------------+---------------+
/ Timestamp | RESERVED |
+-----------------------------------------------+---------------+
| |
| |
| |
| HHIT |
| |
| |
| |
+---------------------------------------------------------------+
Page 1:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | Trust Timestamp /
+---------------+---------------+-------------------------------+
/ | RESERVED | |
+---------------+---------------+ |
| |
| |
| |
| HHIT Signature |
| |
| |
| |
+---------------------------------------------------------------+
Page 2:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
Wiethuechter, et al. Expires April 20, 2020 [Page 13]
Internet-Draft TM-RID Auth Formats October 2019
| |
| HHIT Signature |
| |
| |
| |
| |
+---------------------------------------------------------------+
Page 3:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| |
| HHIT Signature |
| |
| |
| |
| |
+---------------------------------------------------------------+
Page 4:
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+---------------+-----------------------------------------------+
| Msg. Header | |
+---------------+ |
| |
| |
| |
| |
| Payload |
| |
| |
| |
| |
+---------------------------------------------------------------+
HHIT
16 byte HHIT of EdDSA25519 HI.
Trust Timestamp
4 byte message trust until timestamp.
Wiethuechter, et al. Expires April 20, 2020 [Page 14]
Internet-Draft TM-RID Auth Formats October 2019
HHIT signature
64 byte Signature of whole message.
Payload
0 to n bytes of payload. Max of n is 23.
In this format the Payload could be anything that fits within the 23
bytes. A further two btyes could be used for payload (by removing)
the RESERVED sections allowing for 25 bytes of payload.
6.2.1. Specific Use Case: Trusted Messages
This document suggests the creation of a "Trusted Message".
One specific use case that is useful in the RID space is the creation
of a "Trusted Vector Message". By placing a previous [or new] vector
message into the Payload section of the Authentication Message a
verifiable broadcast can be created.
Due to being signed this creates an authentic vector that is hard to
spoof, which can confirm flight paths in real time.
This model can be applied to any of the Broadcast RID messages in the
ASTM standard as they all fit within the max of 25 bytes.
6.3. HIP Based Offline Authentication
This specific format does not currently fit within the ASTM
specification. Requiring a minimum of 200 bytes, this would require
the Authentication Message to have 10 pages, instead of the current 5
page limit.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| DEV HHIT |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| TIMESTAMP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| DEV HHIT |
| SIG |
. .
. .
. .
Wiethuechter, et al. Expires April 20, 2020 [Page 15]
Internet-Draft TM-RID Auth Formats October 2019
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| DEV HI |
| |
| |
| |
| |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| AUTH TIMESTAMP |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| AUTH HHIT |
| |
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
| AUTH |
| SIG |
. .
. .
. .
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
/ PAYLOAD /
/ /
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
DEV HHIT 16 byte Dev HHIT of EdDSA25519 HI
TIMESTAMP 4 byte packet trust until timestamp
DEV HHIT SIG 64 byte Signature of whole packet
DEV HI 32 byte Device HI of EdDSA25519 HI
AUTH TIMESTAMP 4 byte Dev HHIT trust until timestamp
AUTH HHIT 16 byte Authorizer's HHIT of EdDSA25519 HI
AUTH SIG 64 byte Signature of Device HHIT-HI
PAYLOAD 0 to n bytes of payload
Length 200 + n bytes
What this will grant, if attainable in future revisions of the ASTM
specification, is the ability to authenticate UA information when the
receiving device of the observer (e.g. a smartphone with a dedicated
RID application) has no Internet service (e.g. LTE signal).
By including the device HI along with a signature from the registry
the UA is under, we can assert trust of a given drone without
requiring the need for immediate reverse lookups online.
Wiethuechter, et al. Expires April 20, 2020 [Page 16]
Internet-Draft TM-RID Auth Formats October 2019
7. IANA Considerations
TBD
8. Security Considerations
TBD
9. Acknowledgments
TBD
10. References
10.1. Normative References
[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>.
[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>.
10.2. Informative References
[I-D.moskowitz-hip-hhit-registries]
Moskowitz, R., Card, S., and A. Wiethuechter,
"Hierarchical HIT Registries", draft-moskowitz-hip-hhit-
registries-01 (work in progress), October 2019.
[I-D.moskowitz-hip-hierarchical-hit]
Moskowitz, R., Card, S., and A. Wiethuechter,
"Hierarchical HITs for HIPv2", draft-moskowitz-hip-
hierarchical-hit-01 (work in progress), October 2019.
[I-D.moskowitz-hip-new-crypto]
Moskowitz, R., Card, S., and A. Wiethuechter, "New
Cryptographic Algorithms for HIP", draft-moskowitz-hip-
new-crypto-02 (work in progress), October 2019.
[RFC6920] Farrell, S., Kutscher, D., Dannewitz, C., Ohlman, B.,
Keranen, A., and P. Hallam-Baker, "Naming Things with
Hashes", RFC 6920, DOI 10.17487/RFC6920, April 2013,
<https://www.rfc-editor.org/info/rfc6920>.
Wiethuechter, et al. Expires April 20, 2020 [Page 17]
Internet-Draft TM-RID Auth Formats October 2019
[RFC7401] Moskowitz, R., Ed., Heer, T., Jokela, P., and T.
Henderson, "Host Identity Protocol Version 2 (HIPv2)",
RFC 7401, DOI 10.17487/RFC7401, April 2015,
<https://www.rfc-editor.org/info/rfc7401>.
Authors' Addresses
Adam Wiethuechter
AX Enterprize
4947 Commercial Drive
Yorkville, NY 13495
USA
Email: adam.wiethuechter@axenterprize.com
Stuart W. Card
AX Enterprize
4947 Commercial Drive
Yorkville, NY 13495
USA
Email: stu.card@axenterprize.com
Robert Moskowitz
HTT Consulting
Oak Park, MI 48237
USA
Email: rgm@labs.htt-consult.com
Wiethuechter, et al. Expires April 20, 2020 [Page 18]