SUIT B. Moran
Internet-Draft H. Tschofenig
Intended status: Standards Track Arm Limited
Expires: August 10, 2020 H. Birkholz
Fraunhofer SIT
February 07, 2020
A Concise Binary Object Representation (CBOR)-based Serialization Format
for the Software Updates for Internet of Things (SUIT) Manifest
draft-ietf-suit-manifest-03
Abstract
This specification describes the format of a manifest. A manifest is
a bundle of metadata about the firmware for an IoT device, where to
find the firmware, the devices to which it applies, and cryptographic
information protecting the manifest.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on August 10, 2020.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Conventions and Terminology . . . . . . . . . . . . . . . . . 5
3. How to use this Document . . . . . . . . . . . . . . . . . . 6
4. Background . . . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. Landscape . . . . . . . . . . . . . . . . . . . . . . . . 6
4.2. Update Workflow Model . . . . . . . . . . . . . . . . . . 7
4.3. SUIT Manifest Goals . . . . . . . . . . . . . . . . . . . 8
4.4. SUIT Manifest Design Summary . . . . . . . . . . . . . . 9
5. Interpreter Behavior . . . . . . . . . . . . . . . . . . . . 10
5.1. Interpreter Setup . . . . . . . . . . . . . . . . . . . . 10
5.2. Required Checks . . . . . . . . . . . . . . . . . . . . . 11
5.3. Interpreter Fundamental Properties . . . . . . . . . . . 12
5.4. Abstract Machine Description . . . . . . . . . . . . . . 12
5.4.1. Parameters . . . . . . . . . . . . . . . . . . . . . 13
5.4.2. Commands . . . . . . . . . . . . . . . . . . . . . . 14
5.4.3. Command Behavior . . . . . . . . . . . . . . . . . . 15
5.5. Serialized Processing Interpreter . . . . . . . . . . . . 16
5.6. Parallel Processing Interpreter . . . . . . . . . . . . . 16
5.7. Processing Dependencies . . . . . . . . . . . . . . . . . 17
6. Creating Manifests . . . . . . . . . . . . . . . . . . . . . 17
6.1. Manifest Source Material . . . . . . . . . . . . . . . . 18
6.2. Required Template: Compatibility Check . . . . . . . . . 18
6.3. Use Case Template: XIP Secure Boot . . . . . . . . . . . 19
6.4. Use Case Template: Firmware Download . . . . . . . . . . 20
6.5. Use Case Template: Load from External Storage . . . . . . 20
6.6. Use Case Template Load & Decompress from External Storage 20
6.7. Use Case Template: Dependency . . . . . . . . . . . . . . 21
7. Manifest Structure . . . . . . . . . . . . . . . . . . . . . 21
7.1. Severable Elements . . . . . . . . . . . . . . . . . . . 22
7.2. Outer Wrapper . . . . . . . . . . . . . . . . . . . . . . 23
7.3. Manifest . . . . . . . . . . . . . . . . . . . . . . . . 25
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7.4. SUIT_Dependency . . . . . . . . . . . . . . . . . . . . . 28
7.5. SUIT_Component_Reference . . . . . . . . . . . . . . . . 29
7.6. Manifest Parameters . . . . . . . . . . . . . . . . . . . 29
7.6.1. SUIT_Parameter_Strict_Order . . . . . . . . . . . . . 31
7.6.2. SUIT_Parameter_Soft_Failure . . . . . . . . . . . . . 32
7.7. SUIT_Parameter_Encryption_Info . . . . . . . . . . . . . 32
7.7.1. SUIT_Parameter_Compression_Info . . . . . . . . . . . 32
7.7.2. SUIT_Parameter_Unpack_Info . . . . . . . . . . . . . 32
7.7.3. SUIT_Parameters CDDL . . . . . . . . . . . . . . . . 33
7.8. SUIT_Command_Sequence . . . . . . . . . . . . . . . . . . 35
7.9. SUIT_Condition . . . . . . . . . . . . . . . . . . . . . 36
7.9.1. Identifier Conditions . . . . . . . . . . . . . . . . 37
7.9.2. suit-condition-image-match . . . . . . . . . . . . . 38
7.9.3. suit-condition-image-not-match . . . . . . . . . . . 38
7.9.4. suit-condition-use-before . . . . . . . . . . . . . . 38
7.9.5. suit-condition-minimum-battery . . . . . . . . . . . 38
7.9.6. suit-condition-update-authorized . . . . . . . . . . 38
7.9.7. suit-condition-version . . . . . . . . . . . . . . . 39
7.9.8. SUIT_Condition_Custom . . . . . . . . . . . . . . . . 40
7.9.9. Identifiers . . . . . . . . . . . . . . . . . . . . . 40
7.9.10. SUIT_Condition CDDL . . . . . . . . . . . . . . . . . 41
7.10. SUIT_Directive . . . . . . . . . . . . . . . . . . . . . 42
7.10.1. suit-directive-set-component-index . . . . . . . . . 43
7.10.2. suit-directive-set-dependency-index . . . . . . . . 44
7.10.3. suit-directive-abort . . . . . . . . . . . . . . . . 44
7.10.4. suit-directive-run-sequence . . . . . . . . . . . . 44
7.10.5. suit-directive-try-each . . . . . . . . . . . . . . 45
7.10.6. suit-directive-process-dependency . . . . . . . . . 45
7.10.7. suit-directive-set-parameters . . . . . . . . . . . 46
7.10.8. suit-directive-override-parameters . . . . . . . . . 46
7.10.9. suit-directive-fetch . . . . . . . . . . . . . . . . 47
7.10.10. suit-directive-copy . . . . . . . . . . . . . . . . 47
7.10.11. suit-directive-swap . . . . . . . . . . . . . . . . 48
7.10.12. suit-directive-run . . . . . . . . . . . . . . . . . 48
7.10.13. suit-directive-wait . . . . . . . . . . . . . . . . 49
7.10.14. SUIT_Directive CDDL . . . . . . . . . . . . . . . . 50
7.11. SUIT_Text_Map . . . . . . . . . . . . . . . . . . . . . . 52
8. Access Control Lists . . . . . . . . . . . . . . . . . . . . 52
9. SUIT digest container . . . . . . . . . . . . . . . . . . . . 53
10. Creating Conditional Sequences . . . . . . . . . . . . . . . 54
11. Full CDDL . . . . . . . . . . . . . . . . . . . . . . . . . . 56
12. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 63
12.1. Example 0: Secure Boot . . . . . . . . . . . . . . . . . 64
12.2. Example 1: Simultaneous Download and Installation of
Payload . . . . . . . . . . . . . . . . . . . . . . . . 66
12.3. Example 2: Simultaneous Download, Installation, and
Secure Boot . . . . . . . . . . . . . . . . . . . . . . 68
12.4. Example 3: Load from External Storage . . . . . . . . . 69
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12.5. Example 4: Load and Decompress from External Storage . . 72
12.6. Example 5: Compatibility Test, Download, Installation,
and Secure Boot . . . . . . . . . . . . . . . . . . . . 75
12.7. Example 6: Two Images . . . . . . . . . . . . . . . . . 77
13. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 80
14. Security Considerations . . . . . . . . . . . . . . . . . . . 80
15. Mailing List Information . . . . . . . . . . . . . . . . . . 81
16. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 81
17. References . . . . . . . . . . . . . . . . . . . . . . . . . 81
17.1. Normative References . . . . . . . . . . . . . . . . . . 81
17.2. Informative References . . . . . . . . . . . . . . . . . 82
17.3. URIs . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 82
1. Introduction
A firmware update mechanism is an essential security feature for IoT
devices to deal with vulnerabilities. While the transport of
firmware images to the devices themselves is important there are
already various techniques available, such as the Lightweight
Machine-to-Machine (LwM2M) protocol offering device management of IoT
devices. Equally important is the inclusion of meta-data about the
conveyed firmware image (in the form of a manifest) and the use of
end-to-end security protection to detect modifications and
(optionally) to make reverse engineering more difficult. End-to-end
security allows the author, who builds the firmware image, to be sure
that no other party (including potential adversaries) can install
firmware updates on IoT devices without adequate privileges. This
authorization process is ensured by the use of dedicated symmetric or
asymmetric keys installed on the IoT device: for use cases where only
integrity protection is required it is sufficient to install a trust
anchor on the IoT device. For confidentiality protected firmware
images it is additionally required to install either one or multiple
symmetric or asymmetric keys on the IoT device. Starting security
protection at the author is a risk mitigation technique so firmware
images and manifests can be stored on untrusted repositories; it also
reduces the scope of a compromise of any repository or intermediate
system to be no worse than a denial of service.
It is assumed that the reader is familiar with the high-level
firmware update architecture [I-D.ietf-suit-architecture].
The SUIT manifest is heavily optimized for consumption by constrained
devices. This means that it is not constructed as a conventional
descriptive document. Instead, of describing what an update IS, it
describes what a recipient should DO.
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While the SUIT manifest is informed by and optimized for firmware
update use cases, there is nothing in the
[I-D.ietf-suit-information-model] that restricts its use to only
firmware use cases. Software update and delivery of arbitrary data
can equally be managed by SUIT-based metadata.
2. Conventions and 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.
The following terminology is used throughout this document.
- SUIT: Software Update for the Internet of Things, the IETF working
group for this standard.
- Payload: A piece of information to be delivered. Typically
Firmware for the purposes of SUIT.
- Resource: A piece of information that is used to construct a
payload.
- Manifest: A piece of information that describes one or more
payloads, one or more resources, and the processors needed to
transform resources into payloads.
- Update: One or more manifests that describe one or more payloads.
- Update Authority: The owner of a cryptographic key used to sign
updates, trusted by Recipients.
- Recipient: The system, typically an IoT device, that receives a
manifest.
- Condition: A test for a property of the Recipient or its
components.
- Directive: An action for the Recipient to perform.
- Command: A Condition or a Directive.
- Trusted Execution: A process by which a system ensures that only
trusted code is executed, for example secure boot.
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- A/B images: Dividing a device's storage into two or more bootable
images, at different offsets, such that the active image can write
to the inactive image(s).
The map indices in this encoding are reset to 1 for each map within
the structure. This is to keep the indices as small as possible.
The goal is to keep the index objects to single bytes (CBOR positive
integers 1-23).
Wherever enumerations are used, they are started at 1. This allows
detection of several common software errors that are caused by
uninitialised variables. Positive numbers in enumerations are
reserved for IANA registration. Negative numbers are used to
identify application-specific implementations.
CDDL names are hyphenated and CDDL structures follow the convention
adopted in COSE [RFC8152]: SUIT_Structure_Name.
3. How to use this Document
For information about firmware update in general and the background
of the suit manifest, see Section 4. To implement an updatable
device, see Section 5 and Section 7. To implement a tool that
generates updates, see Section 6 and Section 7.
4. Background
Distributing firmware updates to diverse devices with diverse trust
anchors in a coordinated system presents unique challenges. Devices
have a broad set of constraints, requiring different metadata to make
appropriate decisions. There may be many actors in production IoT
systems, each of whom has some authority. Distributing firmware in
such a multi-party environment presents additional challenges. Each
party requires a different subset of data. Some data may not be
accessible to all parties. Multiple signatures may be required from
parties with different authorities. This topic is covered in more
depth in [I-D.ietf-suit-architecture].
4.1. Landscape
The various constraints on IoT devices creates a broad set of use-
case requirements. For example, devices with:
- limited processing power and storage may require a simple
representation of metadata.
- bandwidth constraints may require firmware compression or partial
update support.
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- bootloader complexity constraints may require simple selection
between two bootable images.
- small internal storage may require external storage support.
- multiple processors may require coordinated update of all
applications.
- large storage and complex functionality may require parallel
update of many software components.
- mesh networks may require multicast distribution.
Supporting the requirements introduced by the constraints on IoT
devices requires the flexibility to represent a diverse set of
possible metadata, but also requires that the encoding is kept
simple.
4.2. Update Workflow Model
There are several fundamental assumptions that inform the model of
the firmware update workflow:
- Compatibility must be checked before any other operation is
performed.
- All dependency manifests should be present before any payload is
fetched.
- In some applications, payloads must be fetched and validated prior
to installation.
There are several fundamental assumptions that inform the model of
the secure boot workflow:
- Compatibility must be checked before any other operation is
performed.
- All dependencies and payloads must be validated prior to loading.
- All loaded images must be validated prior to execution.
Based on these assumptions, the manifest is structured to work with a
pull parser, where each section of the manifest is used in sequence.
The expected workflow for a device installing an update can be broken
down into 5 steps:
1. Verify the signature of the manifest.
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2. Verify the applicability of the manifest.
3. Resolve dependencies.
4. Fetch payload(s).
5. Install payload(s).
When installation is complete, similar information can be used for
validating and running images in a further 3 steps:
1. Verify image(s).
2. Load image(s).
3. Run image(s).
If verification and running is implemented in bootloader, then the
When multiple manifests are used for an update, each manifest's steps
occur in a lockstep fashion; all manifests have dependency resolution
performed before any manifest performs a payload fetch, etc.
4.3. SUIT Manifest Goals
The manifest described in this document is intended to meet several
goals, as described below.
1. Meet the requirements defined in
[I-D.ietf-suit-information-model].
2. Simple to parse on a constrained node
3. Simple to process on a constrained node
4. Compact encoding
5. Comprehensible by an intermediate system
6. Expressive enough to enable advanced use cases on advanced nodes
7. Extensible
The SUIT manifest can be used for a variety of purposes throughout
its lifecycle. The manifest allows:
1. the Firmware Author to reason about releasing a firmware.
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2. the Network Operator to reason about compatibility of a firmware.
3. the Device Operator to reason about the impact of a firmware.
4. the Device Operator to manage distribution of firmware to
devices.
5. the Plant Manager to reason about timing and acceptance of
firmware updates.
6. the device to reason about the authority & authenticity of a
firmware prior to installation.
7. the device to reason about the applicability of a firmware.
8. the device to reason about the installation of a firmware.
9. the device to reason about the authenticity & encoding of a
firmware at boot.
Each of these uses happens at a different stage of the manifest
lifecycle, so each has different requirements.
4.4. SUIT Manifest Design Summary
In order to provide flexible behavior to constrained devices, while
still allowing more powerful devices to use their full capabilities,
the SUIT manifest encodes the required behavior of a Recipient
device. Behavior is encoded as a specialized byte code, contained in
a CBOR list. This promotes a flat encoding, which simplifies the
parser. The information encoded by this byte code closely matches
the operations that a device will perform, which promotes ease of
processing. The core operations used by most update and trusted
execution operations are represented in the byte code. The byte code
can be extended by registering new operations.
The specialized byte code approach gives benefits equivalent to those
provided by a scripting language or conventional byte code, with two
substantial differences. First, the language is extremely high
level, consisting of only the operations that a device may perform
during update and trusted execution of a firmware image. Second, the
language specifies behaviors in a linearized form, without reverse
branches. Conditional processing is supported, and parallel and out-
of-order processing may be performed by sufficiently capable devices.
By structuring the data in this way, the manifest processor becomes a
very simple engine that uses a pull parser to interpret the manifest.
This pull parser invokes a series of command handlers that evaluate a
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Condition or execute a Directive. Most data is structured in a
highly regular pattern, which simplifies the parser.
The results of this allow a Recipient to implement a very small
parser for constrained applications. If needed, such a parser also
allows the Recipient to perform complex updates with reduced
overhead. Conditional execution of commands allows a simple device
to perform important decisions at validation-time.
Dependency handling is vastly simplified as well. Dependencies
function like subroutines of the language. When a manifest has a
dependency, it can invoke that dependency's commands and modify their
behavior by setting parameters. Because some parameters come with
security implications, the dependencies also have a mechanism to
reject modifications to parameters on a fine-grained level.
Developing a robust permissions system works in this model too. The
Recipient can use a simple ACL that is a table of Identities and
Component Identifier permissions to ensure that only manifests
authenticated by the appropriate identity have access to operate on a
component.
Capability reporting is similarly simplified. A Recipient can report
the Commands, Parameters, Algorithms, and Component Identifiers that
it supports. This is sufficiently precise for a manifest author to
create a manifest that the Recipient can accept.
The simplicity of design in the Recipient due to all of these
benefits allows even a highly constrained platform to use advanced
update capabilities.
5. Interpreter Behavior
This section describes the behavior of the manifest interpreter.
This section focuses primarily on interpreting commands in the
manifest. However, there are several other important behaviors of
the interpreter: encoding version detection, rollback protection, and
authenticity verification are chief among these.
5.1. Interpreter Setup
Prior to executing any command sequence, the interpreter or its host
application MUST inspect the manifest version field and fail when it
encounters an unsupported encoding version. Next, the interpreter or
its host application MUST extract the manifest sequence number and
perform a rollback check using this sequence number. The exact logic
of rollback protection may vary by application, but it has the
following properties:
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- Whenever the interpreter can choose between several manifests, it
MUST select the latest valid manifest, authentic manifest.
- If the latest valid, authentic manifest fails, it MAY select the
next latest valid, authentic manifest.
Here, valid means that a manifest has a supported encoding version
AND it has not been excluded for other reasons. Reasons for
excluding typically involve first executing the manifest and MAY
include:
- Test failed (e.g. Vendor ID/Class ID).
- Unsupported command encountered.
- Unsupported parameter encountered.
- Unsupported component ID encountered.
- Payload not available (update interpreter).
- Dependency not available (update interpreter).
- Application crashed when executed (bootloader interpreter).
- Watchdog timeout occurred (bootloader interpreter).
- Dependency or Payload verification failed (bootloader
interpreter).
These failure reasons MAY be combined with retry mechanisms prior to
marking a manifest as invalid.
Following these initial tests, the interpreter clears all parameter
storage. This ensures that the interpreter begins without any leaked
data.
5.2. Required Checks
Once a valid, authentic manifest has been selected, the interpreter
MUST examine the component list and verify that its maximum number of
components is not exceeded and that each listed component ID is
supported.
For each listed component, the interpreter MUST provide storage for
the supported parameters (Section 5.4.1). If the interpreter does
not have sufficient temporary storage to process the parameters for
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all components, it MAY process components serially for each command
sequence. See Section 5.5 for more details.
The interpreter SHOULD check that the common section contains at
least one vendor ID check and at least one class ID check.
If the manifest contains more than one component, each command
sequence MUST begin with a Set Current Component command.
If a dependency is specified, then the interpreter MUST perform the
following checks:
1. At the beginning of each section in the dependent: all previous
sections of each dependency have been executed.
2. At the end of each section in the dependent: The corresponding
section in each dependency has been executed.
If the interpreter does not support dependencies and a manifest
specifies a dependency, then the interpreter MUST reject the
manifest.
5.3. Interpreter Fundamental Properties
The interpreter has a small set of design goals:
1. Executing an update MUST either result in an error, or a
verifiably correct system state.
2. Executing a secure boot MUST either result in an error, or a
booted system.
3. Executing the same manifest on multiple devices MUST result in
the same system state.
NOTE: when using A/B images, the manifest functions as two (or more)
logical manifests, each of which applies to a system in a particular
starting state. With that provision, design goal 3 holds.
5.4. Abstract Machine Description
The byte code that forms the bulk of the manifest is processed by an
interpreter. This interpreter can be modeled as a simple abstract
machine. This machine consists of several data storage locations
that are modified by commands. Certain commands also affect the
machine's behavior.
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Every command that modifies system state targets a specific
component. Components are units of code or data that can be targeted
by an update. They are identified by Component identifiers, arrays
of binary-strings-effectively a binary path. Each component has a
corresponding set of configuration, Parameters. Parameters are used
as the inputs to commands.
5.4.1. Parameters
Some parameters are REQUIRED to implement. These parameters allow a
device to perform core functions.
- Vendor ID.
- Class ID.
- Image Digest.
Some parameters are RECOMMENDED to implement. These parameters are
needed for most use-cases.
- Image Size.
- URI.
Other parameters are OPTIONAL to implement. These parameters allow a
device to implement specific use-cases.
- Strict Order.
- Soft Failure.
- Device ID.
- Encryption Info.
- Unpack Info.
- Source Component.
- URI List.
- Custom Parameters.
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5.4.2. Commands
Commands define the behavior of a device. The commands are divided
into two groups: those that modify state (directives) and those that
perform tests (conditions). There are also several Control Flow
operations.
Some commands are REQUIRED to implement. These commands allow a
device to perform core functions
- Check Vendor Identifier (cvid).
- Check Class Identifier (ccid).
- Verify Image (cimg).
- Set Current Component (setc).
- Override Parameters (ovrp).
NOTE: on systems that support only a single component, Set Current
Component has no effect.
Some commands are RECOMMENDED to implement. These commands are
needed for most use-cases
- Set Current Dependency (setd).
- Set Parameters (setp).
- Process Dependency (pdep).
- Run (run).
- Fetch (getc).
Other commands are OPTIONAL to implement. These commands allow a
device to implement specific use-cases.
- Use Before (ubf).
- Check Component Offset (cco).
- Check Device Identifier (cdid).
- Check Image Not Match (nimg).
- Check Minimum Battery (minb).
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- Check Update Authorized (auth).
- Check Version (cver).
- Abort (abrt).
- Try Each (try).
- Copy (copy).
- Swap (swap).
- Wait For Event (wfe).
- Run Sequence (srun) mandatory component set.
- Run with Arguments (arun).
5.4.3. Command Behavior
The following table describes the behavior of each command. "params"
represents the parameters for the current component or dependency.
+------+------------------------------------------------------------+
| Code | Operation |
+------+------------------------------------------------------------+
| cvid | binary-match(component, params[vendor-id]) |
| | |
| ccid | binary-match(component, params[class-id]) |
| | |
| cimg | binary-match(digest(component), params[digest]) |
| | |
| setc | component := components[arg] |
| | |
| ovrp | params[k] := v for k,v in arg |
| | |
| setd | dependency := dependencies[arg] |
| | |
| setp | params[k] := v if not k in params for k,v in arg |
| | |
| pdep | exec(dependency[common]); exec(dependency[current- |
| | segment]) |
| | |
| run | run(component) |
| | |
| getc | store(component, fetch(params[uri])) |
| | |
| ubf | assert(now() < arg) |
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| | |
| cco | assert(offsetof(component) == arg) |
| | |
| cdid | binary-match(component, params[device-id]) |
| | |
| nimg | not binary-match(digest(component), params[digest]) |
| | |
| minb | assert(battery >= arg) |
| | |
| auth | assert(isAuthorized()) |
| | |
| cver | assert(version_check(component, arg)) |
| | |
| abrt | assert(0) |
| | |
| try | break if exec(seq) is not error for seq in arg |
| | |
| copy | store(component, params[src-component]) |
| | |
| swap | swap(component, params[src-component]) |
| | |
| wfe | until event(arg), wait |
| | |
| srun | exec(arg) |
| | |
| arun | run(component, arg) |
+------+------------------------------------------------------------+
5.5. Serialized Processing Interpreter
Because each manifest has a list of components and a list of
components defined by its dependencies, it is possible for the
manifest processor to handle one component at a time, traversing the
manifest tree once for each listed component. In this mode, the
interpreter ignores any commands executed while the component index
is not the current component. This reduces the overall volatile
storage required to process the update so that the only limit on
number of components is the size of the manifest. However, this
approach requires additional processing power.
5.6. Parallel Processing Interpreter
Advanced devices may make use of the Strict Order parameter and
enable parallel processing of some segments, or it may reorder some
segments. To perform parallel processing, once the Strict Order
parameter is set to False, the device may fork a process for each
command until the Strict Order parameter is returned to True or the
command sequence ends. Then, it joins all forked processes before
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continuing processing of commands. To perform out-of-order
processing, a similar approach is used, except the device consumes
all commands after the Strict Order parameter is set to False, then
it sorts these commands into its preferred order, invokes them all,
then continues processing.
Under each of these scenarios the parallel processing must halt:
- Set Parameters.
- Override Parameters.
- Set Strict Order = True.
- Set Dependency Index.
- Set Component Index.
To perform more useful parallel operations, sequences of commands may
be collected in a suit-directive-run-sequence. Then, each of these
sequences may be run in parallel. Each sequence defaults to Strict
Order = True. To isolate each sequence from each other sequence,
each sequence must declare a single target component. Set Component
Index is not permitted inside this sequence.
5.7. Processing Dependencies
As described in Section 5.2, each manifest must invoke each of its
dependencies sections from the corresponding section of the
dependent. Any changes made to parameters by the dependency persist
in the dependent.
When a Process Dependency command is encountered, the interpreter
loads the dependency identified by the Current Dependency Index. The
interpreter first executes the common-sequence section of the
identified dependency, then it executes the section of the dependency
that corresponds to the currently executing section of the dependent.
The interpreter also performs the checks described in Section 5.2 to
ensure that the dependent is processing the dependency correctly.
6. Creating Manifests
Manifests are created using tools for constructing COSE structures,
calculating cryptographic values and compiling desired system state
into a sequence of operations required to achieve that state. The
process of constructing COSE structures is covered in [RFC8152] and
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the calculation of cryptographic values is beyond the scope of this
document.
Compiling desired system state into a sequence of operations can be
accomplished in many ways, however several templates are provided
here to cover common use-cases. Many of these templates can be
aggregated to produce more complex behavior.
NOTE: On systems that support only a single component, Set Current
Component has no effect and can be omitted.
NOTE: Digest should always be set using Override Parameters, since
this prevents a less-privileged dependent from replacing the digest.
6.1. Manifest Source Material
When a manifest is constructed from a descriptive document, the
descriptive document SHOULD be included in the severable text
section. This section MAY be pruned from the manifest prior to
distribution to a device. The inclusion of text source material
enables several use-cases on unconstrained intermediate systems,
where small manifest size, low parser complexity, and pull parsing
are not required.
An unconstrained system that makes decisions based on the manifest
can use the source material instead so that it does not need to
execute the manifest.
An unconstrained system that presents data to a user can do so
according to typical usage patterns without first executing the
manifest, and can trust that information with the same level of
confidence as the manifest itself.
A verifier can be constructed to emulate execution the manifest and
compare the results of that execution to the source material,
providing a check that the manifest performs its stated objectives
and that the manifest does not exceed the capabilities of the target
device.
6.2. Required Template: Compatibility Check
The compatibility check ensures that devices only install compatible
images.
Common: Set Current Component Check Vendor Identifier Check Class
Identifier
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All manifests MUST contain the compatibility check template, except
as outlined below.
If a device class has a unique trust anchor, and every element in its
trust chain is unique-different from every element in any other
device class, then it MAY include the compatibility check.
If a manifest includes a dependency that performs a compatibility
check, then the dependent manifest MAY include the compatibility
check.
The compatibility check template contains a data dependency: Vendor
Identifier and Class Identifier MUST be set prior to executing the
template. One example of the full template is included below,
however Parameters may be set within a Try-Each block as well. They
may also be inherited from a dependent manifest.
- Common:
o Set Current Component.
o Set Parameters:
* Vendor ID.
* Class ID.
o Check Vendor Identifier.
o Check Class Identifier.
6.3. Use Case Template: XIP Secure Boot
- Common:
o Set Current Component.
o Override Parameters:
* Digest.
* Size.
- Run:
o Set Current Component.
o Check Image Match.
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o Directive Run.
6.4. Use Case Template: Firmware Download
- Common:
o Set Current Component.
o Override Parameters:
* Digest.
* Size.
- Install:
o Set Current Component.
o Set Parameters:
* URI.
o Fetch.
6.5. Use Case Template: Load from External Storage
- Load:
o Set Current Component.
o Set Parameters:
* Source Index.
o Copy.
6.6. Use Case Template Load & Decompress from External Storage
- Load:
o Set Current Component.
o Set Parameters:
* Source Index.
* Compression Info.
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o Copy.
6.7. Use Case Template: Dependency
- Dependency Resolution:
o Set Current Dependency.
o Set Parameters:
* URI.
o Fetch.
o Check Image Match.
o Process Dependency.
- Validate:
o Set Current Dependency.
o Check Image Match.
o Process Dependency.
For any other section that the dependency has, the dependent MUST
invoke Process Dependency.
NOTE: Any changes made to parameters in a dependency persist in the
dependent.
7. Manifest Structure
The manifest is divided into several sections in a hierarchy as
follows:
1. The outer wrapper
1. Authentication delegation chain(s)
2. The authentication wrapper
3. The manifest
1. Critical Information
2. Information shared by all command sequences
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1. List of dependencies
2. List of payloads
3. List of payloads in dependencies
4. Common list of conditions, directives
3. Dependency resolution Reference or list of conditions,
directives
4. Payload fetch Reference or list of conditions,
directives
5. Installation Reference or list of conditions,
directives
6. Verification conditions/directives
7. Load conditions/directives
8. Run conditions/directives
9. Text / Reference
10. COSWID / Reference
4. Dependency resolution conditions/directives
5. Payload fetch conditions/directives
6. Installation conditions/directives
7. Text
8. COSWID / Reference
9. Intermediate Certificate(s) / CWTs
10. Inline Payload(s)
7.1. Severable Elements
Because the manifest can be used by different actors at different
times, some parts of the manifest can be removed without affecting
later stages of the lifecycle. This is called "Severing." Severing
of information is achieved by separating that information from the
signed container so that removing it does not affect the signature.
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This means that ensuring authenticity of severable parts of the
manifest is a requirement for the signed portion of the manifest.
Severing some parts makes it possible to discard parts of the
manifest that are no longer necessary. This is important because it
allows the storage used by the manifest to be greatly reduced. For
example, no text size limits are needed if text is removed from the
manifest prior to delivery to a constrained device.
Elements are made severable by removing them from the manifest,
encoding them in a bstr, and placing a SUIT_Digest of the bstr in the
manifest so that they can still be authenticated. The SUIT_Digest
typically consumes 4 bytes more than the size of the raw digest,
therefore elements smaller than (Digest Bits)/8 + 4 SHOULD never be
severable. Elements larger than (Digest Bits)/8 + 4 MAY be
severable, while elements that are much larger than (Digest Bits)/8 +
4 SHOULD be severable.
Because of this, all command sequences in the manifest are encoded in
a bstr so that there is a single code path needed for all command
sequences
7.2. Outer Wrapper
This object is a container for the other pieces of the manifest to
provide a common mechanism to find each of the parts. All elements
of the outer wrapper are contained in bstr objects. Wherever the
manifest references an object in the outer wrapper, the bstr is
included in the digest calculation.
The CDDL that describes the wrapper is below
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SUIT_Outer_Wrapper = {
suit-delegation => bstr .cbor SUIT_Delegation
suit-authentication-wrapper => bstr .cbor
SUIT_Authentication_Wrapper / nil,
$SUIT_Manifest_Wrapped,
? suit-dependency-resolution => bstr .cbor SUIT_Command_Sequence,
? suit-payload-fetch => bstr .cbor SUIT_Command_Sequence,
? suit-install => bstr .cbor SUIT_Command_Sequence,
? suit-text => bstr .cbor SUIT_Text_Map,
? suit-coswid => bstr .cbor COSWID
}
SUIT_Delegation = [ + [ + CWT ] ]
SUIT_Authentication_Wrapper = [ + (COSE_Mac_Tagged / COSE_Sign_Tagged /
COSE_Mac0_Tagged / COSE_Sign1_Tagged)]
SUIT_Encryption_Wrapper = COSE_Encrypt_Tagged / COSE_Encrypt0_Tagged
SUIT_Manifest_Wrapped //= (suit-manifest => bstr .cbor SUIT_Manifest)
SUIT_Manifest_Wrapped //= (
suit-manifest-encryption-info => bstr .cbor SUIT_Encryption_Wrapper,
suit-manifest-encrypted => bstr
)
All elements of the outer wrapper must be wrapped in a bstr to
minimize the complexity of the code that evaluates the cryptographic
integrity of the element and to ensure correct serialization for
integrity and authenticity checks.
The suit-authentication-wrapper contains a list of 1 or more
cryptographic authentication wrappers for the core part of the
manifest. These are implemented as COSE_Mac_Tagged or
COSE_Sign_Tagged blocks. The Manifest is authenticated by these
blocks in "detached payload" mode. The COSE_Mac_Tagged and
COSE_Sign_Tagged blocks are described in RFC 8152 [RFC8152] and are
beyond the scope of this document. The suit-authentication-wrapper
MUST come first in the SUIT_Outer_Wrapper, regardless of canonical
encoding of CBOR. All validators MUST reject any SUIT_Outer_Wrapper
that begins with any element other than a suit-authentication-
wrapper.
A manifest that has not had authentication information added MUST
still contain the suit-authentication-wrapper element, but the
content MUST be nil.
The outer wrapper MUST contain only one of
- a plaintext manifest: SUIT_Manifest.
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- an encrypted manifest: both a SUIT_Encryption_Wrapper and the
ciphertext of a manifest.
When the outer wrapper contains SUIT_Encryption_Wrapper, the suit-
authentication-wrapper MUST authenticate the plaintext of suit-
manifest-encrypted.
suit-manifest contains a SUIT_Manifest structure, which describes the
payload(s) to be installed and any dependencies on other manifests.
suit-manifest-encryption-info contains a SUIT_Encryption_Wrapper, a
COSE object that describes the information required to decrypt a
ciphertext manifest.
suit-manifest-encrypted contains a ciphertext manifest.
Each of suit-dependency-resolution, suit-payload-fetch, and suit-
payload-installation contain the severable contents of the
identically named portions of the manifest, described in Section 7.3.
suit-text contains all the human-readable information that describes
any and all parts of the manifest, its payload(s) and its
resource(s).
suit-coswid contains a Concise Software Identifier. This may be
discarded by the Recipient if not needed.
7.3. Manifest
The manifest describes the critical metadata for the referenced
payload(s). In addition, it contains:
1. a version number for the manifest structure itself
2. a sequence number
3. a list of dependencies
4. a list of components affected
5. a list of components affected by dependencies
6. a reference for each of the severable blocks.
7. a list of actions that the Recipient should perform.
The following CDDL fragment defines the manifest.
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SUIT_Manifest = {
suit-manifest-version
=> 1,
suit-manifest-sequence-number
=> uint,
suit-common
=> bstr .cbor SUIT_Common,
? suit-dependency-resolution
=> Digest / bstr .cbor SUIT_Command_Sequence,
? suit-payload-fetch
=> Digest / bstr .cbor SUIT_Command_Sequence,
? suit-install
=> Digest / bstr .cbor SUIT_Command_Sequence,
? suit-validate
=> bstr .cbor SUIT_Command_Sequence,
? suit-load
=> bstr .cbor SUIT_Command_Sequence,
? suit-run
=> bstr .cbor SUIT_Command_Sequence,
? suit-text
=> Digest,
? suit-coswid
=> Digest / bstr .cbor concise-software-identity,
}
SUIT_Common = {
? suit-dependencies
=> bstr .cbor [ + SUIT_Dependency ],
? suit-components
=> bstr .cbor [ + SUIT_Component_Identifier ],
? suit-dependency-components
=> bstr .cbor [ + SUIT_Component_Reference ],
? suit-common-sequence
=> bstr .cbor SUIT_Command_Sequence,
}
Several fields in the Manifest can be either a CBOR structure or a
SUIT_Digest. In each of these cases, the SUIT_Digest provides for a
severable field. Severable fields are RECOMMENDED to implement. In
particular, text SHOULD be severable, since most useful text elements
occupy more space than a SUIT_Digest, but are not needed by the
Recipient. Because SUIT_Digest is a CBOR Array and each severable
element is a CBOR bstr, it is straight-forward for a Recipient to
determine whether an element is been severable. The key used for a
severable element is the same in the SUIT_Manifest and in the
SUIT_Outer_Wrapper so that a Recipient can easily identify the
correct data in the outer wrapper.
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The suit-manifest-version indicates the version of serialization used
to encode the manifest. Version 1 is the version described in this
document. suit-manifest-version is REQUIRED.
The suit-manifest-sequence-number is a monotonically increasing anti-
rollback counter. It also helps devices to determine which in a set
of manifests is the "root" manifest in a given update. Each manifest
MUST have a sequence number higher than each of its dependencies.
Each Recipient MUST reject any manifest that has a sequence number
lower than its current sequence number. It MAY be convenient to use
a UTC timestamp in seconds as the sequence number. suit-manifest-
sequence-number is REQUIRED.
suit-common encodes all the information that is shared between each
of the command sequences, including: suit-dependencies, suit-
components, suit-dependency-components, and suit-common-sequence.
suit-common is REQUIRED to implement.
suit-dependencies is a list of SUIT_Dependency blocks that specify
manifests that must be present before the current manifest can be
processed. suit-dependencies is OPTIONAL to implement.
In order to distinguish between components that are affected by the
current manifest and components that are affected by a dependency,
they are kept in separate lists. Components affected by the current
manifest only list the component identifier. Components affected by
a dependency include the component identifier and the index of the
dependency that defines the component.
suit-components is a list of SUIT_Component blocks that specify the
component identifiers that will be affected by the content of the
current manifest. suit-components is OPTIONAL, but at least one
manifest MUST contain a suit-components block.
suit-dependency-components is a list of SUIT_Component_Reference
blocks that specify component identifiers that will be affected by
the content of a dependency of the current manifest. suit-dependency-
components is OPTIONAL.
suit-common-sequence is a SUIT_Command_Sequence to execute prior to
executing any other command sequence. Typical actions in suit-
common-sequence include setting expected device identity and image
digests when they are conditional (see Section 10 for more
information on conditional sequences). suit-common-sequence is
RECOMMENDED.
suit-dependency-resolution is a SUIT_Command_Sequence to execute in
order to perform dependency resolution. Typical actions include
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configuring URIs of dependency manifests, fetching dependency
manifests, and validating dependency manifests' contents. suit-
dependency-resolution is REQUIRED when suit-dependencies is present.
suit-payload-fetch is a SUIT_Command_Sequence to execute in order to
obtain a payload. Some manifests may include these actions in the
suit-install section instead if they operate in a streaming
installation mode. This is particularly relevant for constrained
devices without any temporary storage for staging the update. suit-
payload-fetch is OPTIONAL.
suit-install is a SUIT_Command_Sequence to execute in order to
install a payload. Typical actions include verifying a payload
stored in temporary storage, copying a staged payload from temporary
storage, and unpacking a payload. suit-install is OPTIONAL.
suit-validate is a SUIT_Command_Sequence to execute in order to
validate that the result of applying the update is correct. Typical
actions involve image validation and manifest validation. suit-
validate is REQUIRED. If the manifest contains dependencies, one
process-dependency invocation per dependency or one process-
dependency invocation targeting all dependencies SHOULD be present in
validate.
suit-load is a SUIT_Command_Sequence to execute in order to prepare a
payload for execution. Typical actions include copying an image from
permanent storage into RAM, optionally including actions such as
decryption or decompression. suit-load is OPTIONAL.
suit-run is a SUIT_Command_Sequence to execute in order to run an
image. suit-run typically contains a single instruction: either the
"run" directive for the bootable manifest or the "process
dependencies" directive for any dependents of the bootable manifest.
suit-run is OPTIONAL. Only one manifest in an update may contain the
"run" directive.
suit-text is a digest that uniquely identifies the content of the
Text that is packaged in the OuterWrapper. text is OPTIONAL.
suit-coswid is a digest that uniquely identifies the content of the
concise-software-identifier that is packaged in the OuterWrapper.
coswid is OPTIONAL.
7.4. SUIT_Dependency
SUIT_Dependency specifies a manifest that describes a dependency of
the current manifest.
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The following CDDL describes the SUIT_Dependency structure.
SUIT_Dependency = {
suit-dependency-digest => SUIT_Digest,
? suit-dependency-prefix => SUIT_Component_Identifier,
}
The suit-dependency-digest specifies the dependency manifest uniquely
by identifying a particular Manifest structure. The digest is
calculated over the Manifest structure instead of the COSE
Sig_structure or Mac_structure. This means that a digest may need to
be calculated more than once, however this is necessary to ensure
that removing a signature from a manifest does not break dependencies
due to missing signature elements. This is also necessary to support
the trusted intermediary use case, where an intermediary re-signs the
Manifest, removing the original signature, potentially with a
different algorithm, or trading COSE_Sign for COSE_Mac.
The suit-dependency-prefix element contains a
SUIT_Component_Identifier. This specifies the scope at which the
dependency operates. This allows the dependency to be forwarded on
to a component that is capable of parsing its own manifests. It also
allows one manifest to be deployed to multiple dependent devices
without those devices needing consistent component hierarchy. This
element is OPTIONAL.
7.5. SUIT_Component_Reference
The SUIT_Component_Reference describes an image that is defined by
another manifest. This is useful for overriding the behavior of
another manifest, for example by directing the recipient to look at a
different URI for the image or by changing the expected format, such
as when a gateway performs decryption on behalf of a constrained
device. The following CDDL describes the SUIT_Component_Reference.
SUIT_Component_Reference = {
suit-component-identifier => SUIT_Component_Identifier,
suit-component-dependency-index => uint
}
7.6. Manifest Parameters
Many conditions and directives require additional information. That
information is contained within parameters that can be set in a
consistent way. This allows reduction of manifest size and
replacement of parameters from one manifest to the next.
The defined manifest parameters are described below.
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+-----+--------+-------------------+------------+-------------------+
| ID | CBOR | Scope | Name | Description |
| | Type | | | |
+-----+--------+-------------------+------------+-------------------+
| 1 | boolea | Global | Strict | Requires that the |
| | n | | Order | manifest is |
| | | | | processed in a |
| | | | | strictly linear |
| | | | | fashion. Set to 0 |
| | | | | to enable |
| | | | | parallel handling |
| | | | | of manifest |
| | | | | directives. |
| | | | | |
| 2 | boolea | Command Segment | Soft | Condition |
| | n | | Failure | failures only |
| | | | | terminate the |
| | | | | current command |
| | | | | segment. |
| | | | | |
| 3 | bstr | Component/Global | Vendor ID | A RFC4122 UUID |
| | | | | representing the |
| | | | | vendor of the |
| | | | | device or |
| | | | | component |
| | | | | |
| 4 | bstr | Component/Global | Class ID | A RFC4122 UUID |
| | | | | representing the |
| | | | | class of the |
| | | | | device or |
| | | | | component |
| | | | | |
| 5 | bstr | Component/Global | Device ID | A RFC4122 UUID |
| | | | | representing the |
| | | | | device or |
| | | | | component |
| | | | | |
| 6 | tstr | Component/Depende | URI | A URI from which |
| | | ncy | | to fetch a |
| | | | | resource |
| | | | | |
| 7 | bstr | Component/Depende | Encryption | A COSE object |
| | | ncy | Info | defining the |
| | | | | encryption mode |
| | | | | of a resource |
| | | | | |
| 8 | bstr | Component | Compressio | The information |
| | | | n Info | required to |
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| | | | | decompress the |
| | | | | image |
| | | | | |
| 9 | bstr | Component | Unpack | The information |
| | | | Info | required to |
| | | | | unpack the image |
| | | | | |
| 10 | uint | Component | Source | A Component Index |
| | | | Component | |
| | | | | |
| 11 | bstr | Component/Depende | Image | A SUIT_Digest |
| | | ncy | Digest | |
| | | | | |
| 12 | uint | Component/Depende | Image Size | Integer size |
| | | ncy | | |
| | | | | |
| 24 | bstr | Component/Depende | URI List | A CBOR encoded |
| | | ncy | | list of ranked |
| | | | | URIs |
| | | | | |
| 25 | boolea | Component/Depende | URI List | A CBOR encoded |
| | n | ncy | Append | list of ranked |
| | | | | URIs |
| | | | | |
| nin | int/bs | Custom | Custom | Application- |
| t | tr | | Parameter | defined parameter |
+-----+--------+-------------------+------------+-------------------+
CBOR-encoded object parameters are still wrapped in a bstr. This is
because it allows a parser that is aggregating parameters to
reference the object with a single pointer and traverse it without
understanding the contents. This is important for modularization and
division of responsibility within a pull parser. The same
consideration does not apply to Conditions and Directives because
those elements are invoked with their arguments immediately
7.6.1. SUIT_Parameter_Strict_Order
The Strict Order Parameter allows a manifest to govern when
directives can be executed out-of-order. This allows for systems
that have a sensitivity to order of updates to choose the order in
which they are executed. It also allows for more advanced systems to
parallelize their handling of updates. Strict Order defaults to
True. It MAY be set to False when the order of operations does not
matter. When arriving at the end of a command sequence, ALL commands
MUST have completed, regardless of the state of
SUIT_Parameter_Strict_Order. If SUIT_Parameter_Strict_Order is
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returned to True, ALL preceding commands MUST complete before the
next command is executed.
7.6.2. SUIT_Parameter_Soft_Failure
When executing a command sequence inside SUIT_Directive_Try_Each and
a condition failure occurs, the manifest processor aborts the
sequence. If Soft Failure is True, it returns Success. Otherwise,
it returns the original condition failure.
SUIT_Parameter_Soft_Failure is scoped to the enclosing
SUIT_Command_Sequence. Its value is discarded when
SUIT_Command_Sequence terminates.
7.7. SUIT_Parameter_Encryption_Info
Encryption Info defines the mechanism that Fetch or Copy should use
to decrypt the data they transfer. SUIT_Parameter_Encryption_Info is
encoded as a COSE_Encrypt_Tagged or a COSE_Encrypt0_Tagged, wrapped
in a bstr.
7.7.1. SUIT_Parameter_Compression_Info
Compression Info defines any information that is required for a
device to perform decompression operations. Typically, this includes
the algorithm identifier.
SUIT_Parameter_Compression_Info is defined by the following CDDL:
SUIT_Compression_Info = {
suit-compression-algorithm => SUIT_Compression_Algorithms
? suit-compression-parameters => bstr
}
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_gzip
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_bzip2
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_deflate
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_LZ4
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_lzma
7.7.2. SUIT_Parameter_Unpack_Info
SUIT_Unpack_Info defines the information required for a device to
interpret a packed format, such as elf, hex, or binary diff.
SUIT_Unpack_Info is defined by the following CDDL:
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SUIT_Unpack_Info = {
suit-unpack-algorithm => SUIT_Unpack_Algorithms
? suit-unpack-parameters => bstr
}
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Delta
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Hex
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Elf
7.7.3. SUIT_Parameters CDDL
The following CDDL describes all SUIT_Parameters.
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SUIT_Parameters //= (suit-parameter-strict-order => bool)
SUIT_Parameters //= (suit-parameter-soft-failure => bool)
SUIT_Parameters //= (suit-parameter-vendor-id => bstr)
SUIT_Parameters //= (suit-parameter-class-id => bstr)
SUIT_Parameters //= (suit-parameter-device-id => bstr)
SUIT_Parameters //= (suit-parameter-uri => tstr)
SUIT_Parameters //= (suit-parameter-encryption-info
=> bstr .cbor SUIT_Encryption_Info)
SUIT_Parameters //= (suit-parameter-compression-info
=> bstr .cbor SUIT_Compression_Info)
SUIT_Parameters //= (suit-parameter-unpack-info
=> bstr .cbor SUIT_Unpack_Info)
SUIT_Parameters //= (suit-parameter-source-component
=> uint)
SUIT_Parameters //= (suit-parameter-image-digest
=> bstr .cbor SUIT_Digest)
SUIT_Parameters //= (suit-parameter-image-size => uint)
SUIT_Parameters //= (suit-parameter-uri-list
=> bstr .cbor SUIT_Component_URI_List)
SUIT_Parameters //= (suit-parameter-custom
=> int/bool/tstr/bstr)
SUIT_Component_URI_List = [ + [priority: int, uri: tstr] ]
SUIT_Encryption_Info= COSE_Encrypt_Tagged/COSE_Encrypt0_Tagged
SUIT_Compression_Info = {
suit-compression-algorithm => SUIT_Compression_Algorithms
? suit-compression-parameters => bstr
}
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_gzip
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_bzip2
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_deflate
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_LZ4
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_lzma
SUIT_Unpack_Info = {
suit-unpack-algorithm => SUIT_Unpack_Algorithms
? suit-unpack-parameters => bstr
}
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Delta
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Hex
SUIT_Unpack_Algorithms //= SUIT_Unpack_Algorithm_Elf
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7.8. SUIT_Command_Sequence
A SUIT_Command_Sequence defines a series of actions that the
Recipient MUST take to accomplish a particular goal. These goals are
defined in the manifest and include:
1. Dependency Resolution
2. Payload Fetch
3. Payload Installation
4. Image Validation
5. Image Loading
6. Run or Boot
Each of these follows exactly the same structure to ensure that the
parser is as simple as possible.
Lists of commands are constructed from two kinds of element:
1. Conditions that MUST be true-any failure is treated as a failure
of the update/load/boot
2. Directives that MUST be executed.
The lists of commands are logically structured into sequences of zero
or more conditions followed by zero or more directives. The
*logical* structure is described by the following CDDL:
Command_Sequence = {
conditions => [ * Condition],
directives => [ * Directive]
}
This introduces significant complexity in the parser, however, so the
structure is flattened to make parsing simpler:
SUIT_Command_Sequence = [ + (SUIT_Condition/SUIT_Directive) ]
Each condition and directive is composed of:
1. A command code identifier
2. An argument block
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Argument blocks are defined for each type of command.
Many conditions and directives apply to a given component, and these
generally grouped together. Therefore, a special command to set the
current component index is provided with a matching command to set
the current dependency index. This index is a numeric index into the
component ID tables defined at the beginning of the document. For
the purpose of setting the index, the two component ID tables are
considered to be concatenated together.
To facilitate optional conditions, a special directive is provided.
It runs several new lists of conditions/directives, one after
another, that are contained as an argument to the directive. By
default, it assumes that a failure of a condition should not indicate
a failure of the update/boot, but a parameter is provided to override
this behavior.
7.9. SUIT_Condition
Conditions are used to define mandatory properties of a system in
order for an update to be applied. They can be pre-conditions or
post-conditions of any directive or series of directives, depending
on where they are placed in the list. Conditions include:
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+----------------+-------------------+----------------------------+
| Condition Code | Condition Name | Argument Type |
+----------------+-------------------+----------------------------+
| 1 | Vendor Identifier | nil |
| | | |
| 2 | Class Identifier | nil |
| | | |
| 3 | Image Match | nil |
| | | |
| 4 | Use Before | Unsigned Integer timestamp |
| | | |
| 5 | Component Offset | Unsigned Integer |
| | | |
| 24 | Device Identifier | nil |
| | | |
| 25 | Image Not Match | nil |
| | | |
| 26 | Minimum Battery | Unsigned Integer |
| | | |
| 27 | Update Authorized | Integer |
| | | |
| 28 | Version | List of Integers |
| | | |
| nint | Custom Condition | bstr |
+----------------+-------------------+----------------------------+
Each condition MUST report a success code on completion. If a
condition reports failure, then the current sequence of commands MUST
terminate. If a Recipient encounters an unknown Condition Code, it
MUST report a failure.
Positive Condition numbers are reserved for IANA registration.
Negative numbers are reserved for proprietary, application-specific
directives.
7.9.1. Identifier Conditions
There are three identifier-based conditions: suit-condition-vendor-
identifier, suit-condition-class-identifier, and suit-condition-
device-identifier. Each of these conditions match a RFC 4122
[RFC4122] UUID that MUST have already been set as a parameter. The
installing device MUST match the specified UUID in order to consider
the manifest valid. These identifiers MAY be scoped by component.
The Recipient uses the ID parameter that has already been set using
the Set Parameters directive. If no ID has been set, this condition
fails. suit-condition-class-identifier and suit-condition-vendor-
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identifier are REQUIRED to implement. suit-condition-device-
identifier is OPTIONAL to implement.
7.9.2. suit-condition-image-match
Verify that the current component matches the digest parameter for
the current component. The digest is verified against the digest
specified in the Component's parameters list. If no digest is
specified, the condition fails. suit-condition-image-match is
REQUIRED to implement.
7.9.3. suit-condition-image-not-match
Verify that the current component does not match the supplied digest.
If no digest is specified, then the digest is compared against the
digest specified in the Components list. If no digest is specified
and the component is not present in the Components list, the
condition fails. suit-condition-image-not-match is OPTIONAL to
implement.
7.9.4. suit-condition-use-before
Verify that the current time is BEFORE the specified time. suit-
condition-use-before is used to specify the last time at which an
update should be installed. One argument is required, encoded as a
POSIX timestamp, that is seconds after 1970-01-01 00:00:00.
Timestamp conditions MUST be evaluated in 64 bits, regardless of
encoded CBOR size. suit-condition-use-before is OPTIONAL to
implement.
7.9.5. suit-condition-minimum-battery
suit-condition-minimum-battery provides a mechanism to test a
device's battery level before installing an update. This condition
is for use in primary-cell applications, where the battery is only
ever discharged. For batteries that are charged, suit-directive-wait
is more appropriate, since it defines a "wait" until the battery
level is sufficient to install the update. suit-condition-minimum-
battery is specified in mWh. suit-condition-minimum-battery is
OPTIONAL to implement.
7.9.6. suit-condition-update-authorized
Request Authorization from the application and fail if not
authorized. This can allow a user to decline an update. Argument is
an integer priority level. Priorities are application defined. suit-
condition-update-authorized is OPTIONAL to implement.
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7.9.7. suit-condition-version
suit-condition-version allows comparing versions of firmware.
Verifying image digests is preferred to version checks because
digests are more precise. The image can be compared as:
- Greater.
- Greater or Equal.
- Equal.
- Lesser or Equal.
- Lesser.
Versions are encoded as a CBOR list of integers. Comparisons are
done on each integer in sequence. Comparison stops after all
integers in the list defined by the manifest have been consumed OR
after a non-equal match has occurred. For example, if the manifest
defines a comparison, "Equal [1]", then this will match all version
sequences starting with 1. If a manifest defines both "Greater or
Equal [1,0]" and "Lesser [1,10]", then it will match versions 1.0.x
up to, but not including 1.10.
The following CDDL describes SUIT_Condition_Version_Argument
SUIT_Condition_Version_Argument = [
suit-condition-version-comparison-type:
SUIT_Condition_Version_Comparison_Types,
suit-condition-version-comparison-value:
SUIT_Condition_Version_Comparison_Value
]
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser
SUIT_Condition_Version_Comparison_Value = [+int]
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While the exact encoding of versions is application-defined, semantic
versions map conveniently. For example,
- 1.2.3 = [1,2,3].
- 1.2-rc3 = [1,2,-1,3].
- 1.2-beta = [1,2,-2].
- 1.2-alpha = [1,2,-3].
- 1.2-alpha4 = [1,2,-3,4].
suit-condition-version is OPTIONAL to implement.
7.9.8. SUIT_Condition_Custom
SUIT_Condition_Custom describes any proprietary, application specific
condition. This is encoded as a negative integer, chosen by the
firmware developer, and a bstr that encodes the parameters passed to
the system that evaluates the condition matching that integer.
SUIT_Condition_Custom is OPTIONAL to implement.
7.9.9. Identifiers
Many conditions use identifiers to determine whether a manifest
matches a given Recipient or not. These identifiers are defined to
be RFC 4122 [RFC4122] UUIDs. These UUIDs are explicitly NOT human-
readable. They are for machine-based matching only.
A device may match any number of UUIDs for vendor or class
identifier. This may be relevant to physical or software modules.
For example, a device that has an OS and one or more applications
might list one Vendor ID for the OS and one or more additional Vendor
IDs for the applications. This device might also have a Class ID
that must be matched for the OS and one or more Class IDs for the
applications.
A more complete example: A device has the following physical
components: 1. A host MCU 2. A WiFi module
This same device has three software modules: 1. An operating system
2. A WiFi module interface driver 3. An application
Suppose that the WiFi module's firmware has a proprietary update
mechanism and doesn't support manifest processing. This device can
report four class IDs:
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1. hardware model/revision
2. OS
3. WiFi module model/revision
4. Application
This allows the OS, WiFi module, and application to be updated
independently. To combat possible incompatibilities, the OS class ID
can be changed each time the OS has a change to its API.
This approach allows a vendor to target, for example, all devices
with a particular WiFi module with an update, which is a very
powerful mechanism, particularly when used for security updates.
7.9.9.1. Creating UUIDs:
UUIDs MUST be created according to RFC 4122 [RFC4122]. UUIDs SHOULD
use versions 3, 4, or 5, as described in RFC4122. Versions 1 and 2
do not provide a tangible benefit over version 4 for this
application.
The RECOMMENDED method to create a vendor ID is: Vendor ID =
UUID5(DNS_PREFIX, vendor domain name)
The RECOMMENDED method to create a class ID is: Class ID =
UUID5(Vendor ID, Class-Specific-Information)
Class-specific information is composed of a variety of data, for
example:
- Model number.
- Hardware revision.
- Bootloader version (for immutable bootloaders).
7.9.10. SUIT_Condition CDDL
The following CDDL describes SUIT_Condition:
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SUIT_Condition //= (suit-condition-vendor-identifier, nil)
SUIT_Condition //= (suit-condition-class-identifier, nil)
SUIT_Condition //= (suit-condition-device-identifier, nil)
SUIT_Condition //= (suit-condition-image-match, nil)
SUIT_Condition //= (suit-condition-image-not-match, nil)
SUIT_Condition //= (suit-condition-use-before, uint)
SUIT_Condition //= (suit-condition-minimum-battery, uint)
SUIT_Condition //= (suit-condition-update-authorized, int)
SUIT_Condition //= (suit-condition-version,
SUIT_Condition_Version_Argument)
SUIT_Condition //= (suit-condition-component-offset, uint)
SUIT_Condition //= (suit-condition-custom, bstr)
SUIT_Condition_Version_Argument = [
suit-condition-version-comparison-type:
SUIT_Condition_Version_Comparison_Types,
suit-condition-version-comparison-value:
SUIT_Condition_Version_Comparison_Value
]
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser
SUIT_Condition_Version_Comparison_Value = [+int]
7.10. SUIT_Directive
Directives are used to define the behavior of the recipient.
Directives include:
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+----------------+----------------------+
| Directive Code | Directive Name |
+----------------+----------------------+
| 12 | Set Component Index |
| | |
| 13 | Set Dependency Index |
| | |
| 14 | Abort |
| | |
| 15 | Try Each |
| | |
| 16 | Reserved |
| | |
| 17 | Reserved |
| | |
| 18 | Process Dependency |
| | |
| 19 | Set Parameters |
| | |
| 20 | Override Parameters |
| | |
| 21 | Fetch |
| | |
| 22 | Copy |
| | |
| 23 | Run |
| | |
| 29 | Wait |
| | |
| 30 | Run Sequence |
| | |
| 31 | Run with Arguments |
| | |
| 32 | Swap |
+----------------+----------------------+
When a Recipient executes a Directive, it MUST report a success code.
If the Directive reports failure, then the current Command Sequence
MUST terminate.
7.10.1. suit-directive-set-component-index
Set Component Index defines the component to which successive
directives and conditions will apply. The supplied argument MUST be
either a boolean or an unsigned integer index into the concatenation
of suit-components and suit-dependency-components. If the following
directives apply to ALL components, then the boolean value "True" is
used instead of an index. True does not apply to dependency
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components. If the following directives apply to NO components, then
the boolean value "False" is used. When suit-directive-set-
dependency-index is used, suit-directive-set-component-index = False
is implied. When suit-directive-set-component-index is used, suit-
directive-set-dependency-index = False is implied.
The following CDDL describes the argument to suit-directive-set-
component-index.
SUIT_Directive_Set_Component_Index_Argument = uint/bool
7.10.2. suit-directive-set-dependency-index
Set Dependency Index defines the manifest to which successive
directives and conditions will apply. The supplied argument MUST be
either a boolean or an unsigned integer index into the dependencies.
If the following directives apply to ALL dependencies, then the
boolean value "True" is used instead of an index. If the following
directives apply to NO dependencies, then the boolean value "False"
is used. When suit-directive-set-component-index is used, suit-
directive-set-dependency-index = False is implied. When suit-
directive-set-dependency-index is used, suit-directive-set-component-
index = False is implied.
Typical operations that require suit-directive-set-dependency-index
include setting a source URI, invoking "Fetch," or invoking "Process
Dependency" for an individual dependency.
The following CDDL describes the argument to suit-directive-set-
dependency-index.
SUIT_Directive_Set_Manifest_Index_Argument = uint/bool
7.10.3. suit-directive-abort
Unconditionally fail. This operation is typically used in
conjunction with suit-directive-try-each.
7.10.4. suit-directive-run-sequence
To enable conditional commands, and to allow several strictly ordered
sequences to be executed out-of-order, suit-directive-run-sequence
allows the manifest processor to execute its argument as a
SUIT_Command_Sequence. The argument must be wrapped in a bstr.
When a sequence is executed, any failure of a condition causes
immediate termination of the sequence.
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The following CDDL describes the SUIT_Run_Sequence argument.
SUIT_Directive_Run_Sequence_Argument = bstr .cbor SUIT_Command_Sequence
When suit-directive-run-sequence completes, it forwards the last
status code that occurred in the sequence. If the Soft Failure
parameter is true, then suit-directive-run-sequence only fails when a
directive in the argument sequence fails.
SUIT_Parameter_Soft_Failure defaults to False when suit-directive-
run-sequence begins. Its value is discarded when suit-directive-run-
sequence terminates.
7.10.5. suit-directive-try-each
This command runs several SUIT_Command_Sequence, one after another,
in a strict order. Use this command to implement a "try/catch-try/
catch" sequence. Manifest processors MAY implement this command.
SUIT_Parameter_Soft_Failure is initialized to True at the beginning
of each sequence. If one sequence aborts due to a condition failure,
the next is started. If no sequence completes without condition
failure, then suit-directive-try-each returns an error. If a
particular application calls for all sequences to fail and still
continue, then an empty sequence (nil) can be added to the Try Each
Argument.
The following CDDL describes the SUIT_Try_Each argument.
SUIT_Directive_Try_Each_Argument = [
+ bstr .cbor SUIT_Command_Sequence,
nil / bstr .cbor SUIT_Command_Sequence
]
7.10.6. suit-directive-process-dependency
Execute the commands in the common section of the current dependency,
followed by the commands in the equivalent section of the current
dependency. For example, if the current section is "fetch payload,"
this will execute "common" in the current dependency, then "fetch
payload" in the current dependency. Once this is complete, the
command following suit-directive-process-dependency will be
processed.
If the current dependency is False, this directive has no effect. If
the current dependency is True, then this directive applies to all
dependencies. If the current section is "common," this directive
MUST have no effect.
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When SUIT_Process_Dependency completes, it forwards the last status
code that occurred in the dependency.
The argument to suit-directive-process-dependency is defined in the
following CDDL.
SUIT_Directive_Process_Dependency_Argument = nil
7.10.7. suit-directive-set-parameters
suit-directive-set-parameters allows the manifest to configure
behavior of future directives by changing parameters that are read by
those directives. When dependencies are used, suit-directive-set-
parameters also allows a manifest to modify the behavior of its
dependencies.
Available parameters are defined in Section 7.6.
If a parameter is already set, suit-directive-set-parameters will
skip setting the parameter to its argument. This provides the core
of the override mechanism, allowing dependent manifests to change the
behavior of a manifest.
The argument to suit-directive-set-parameters is defined in the
following CDDL.
SUIT_Directive_Set_Parameters_Argument = {+ SUIT_Parameters}
N.B.: A directive code is reserved for an optimization: a way to set
a parameter to the contents of another parameter, optionally with
another component ID.
7.10.8. suit-directive-override-parameters
suit-directive-override-parameters replaces any listed parameters
that are already set with the values that are provided in its
argument. This allows a manifest to prevent replacement of critical
parameters.
Available parameters are defined in Section 7.6.
The argument to suit-directive-override-parameters is defined in the
following CDDL.
SUIT_Directive_Override_Parameters_Argument = {+ SUIT_Parameters}
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7.10.9. suit-directive-fetch
suit-directive-fetch instructs the manifest processor to obtain one
or more manifests or payloads, as specified by the manifest index and
component index, respectively.
suit-directive-fetch can target one or more manifests and one or more
payloads. suit-directive-fetch retrieves each component and each
manifest listed in component-index and manifest-index, respectively.
If component-index or manifest-index is True, instead of an integer,
then all current manifest components/manifests are fetched. The
current manifest's dependent-components are not automatically
fetched. In order to pre-fetch these, they MUST be specified in a
component-index integer.
suit-directive-fetch typically takes no arguments unless one is
needed to modify fetch behavior. If an argument is needed, it must
be wrapped in a bstr.
suit-directive-fetch reads the URI or URI List parameter to find the
source of the fetch it performs.
The behavior of suit-directive-fetch can be modified by setting one
or more of SUIT_Parameter_Encryption_Info,
SUIT_Parameter_Compression_Info, SUIT_Parameter_Unpack_Info. These
three parameters each activate and configure a processing step that
can be applied to the data that is transferred during suit-directive-
fetch.
The argument to suit-directive-fetch is defined in the following
CDDL.
SUIT_Directive_Fetch_Argument = nil/bstr
7.10.10. suit-directive-copy
suit-directive-copy instructs the manifest processor to obtain one or
more payloads, as specified by the component index. suit-directive-
copy retrieves each component listed in component-index,
respectively. If component-index is True, instead of an integer,
then all current manifest components are copied. The current
manifest's dependent-components are not automatically copied. In
order to copy these, they MUST be specified in a component-index
integer.
The behavior of suit-directive-copy can be modified by setting one or
more of SUIT_Parameter_Encryption_Info,
SUIT_Parameter_Compression_Info, SUIT_Parameter_Unpack_Info. These
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three parameters each activate and configure a processing step that
can be applied to the data that is transferred during suit-directive-
copy.
*N.B.* Fetch and Copy are very similar. Merging them into one
command may be appropriate.
suit-directive-copy reads its source from
SUIT_Parameter_Source_Component.
The argument to suit-directive-copy is defined in the following CDDL.
SUIT_Directive_Copy_Argument = nil
7.10.11. suit-directive-swap
suit-directive-swap instructs the manifest processor to move the
source to the destination and the destination to the source
simultaneously. Swap has nearly identical semantics to suit-
directive-copy except that suit-directive-swap replaces the source
with the current contents of the destination in an application-
defined way. If SUIT_Parameter_Compression_Info or
SUIT_Parameter_Encryption_Info are present, they must be handled in a
symmetric way, so that the source is decompressed into the
destination and the destination is compressed into the source. The
source is decrypted into the destination and the destination is
encrypted into the source. suit-directive-swap is OPTIONAL to
implement.
7.10.12. suit-directive-run
suit-directive-run directs the manifest processor to transfer
execution to the current Component Index. When this is invoked, the
manifest processor MAY be unloaded and execution continues in the
Component Index. Arguments provided to Run are forwarded to the
executable code located in Component Index, in an application-
specific way. For example, this could form the Linux Kernel Command
Line if booting a Linux device.
If the executable code at Component Index is constructed in such a
way that it does not unload the manifest processor, then the manifest
processor may resume execution after the executable completes. This
allows the manifest processor to invoke suitable helpers and to
verify them with image conditions.
The argument to suit-directive-run is defined in the following CDDL.
SUIT_Directive_Run_Argument = nil/bstr
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7.10.13. suit-directive-wait
suit-directive-wait directs the manifest processor to pause until a
specified event occurs. Some possible events include:
1. Authorization
2. External Power
3. Network availability
4. Other Device Firmware Version
5. Time
6. Time of Day
7. Day of Week
The following CDDL defines the encoding of these events.
SUIT_Wait_Events //= (suit-wait-event-authorization => int)
SUIT_Wait_Events //= (suit-wait-event-power => int)
SUIT_Wait_Events //= (suit-wait-event-network => int)
SUIT_Wait_Events //= (suit-wait-event-other-device-version
=> SUIT_Wait_Event_Argument_Other_Device_Version)
SUIT_Wait_Events //= (suit-wait-event-time => uint); Timestamp
SUIT_Wait_Events //= (suit-wait-event-time-of-day
=> uint); Time of Day (seconds since 00:00:00)
SUIT_Wait_Events //= (suit-wait-event-day-of-week
=> uint); Days since Sunday
SUIT_Wait_Event_Argument_Authorization = int ; priority
SUIT_Wait_Event_Argument_Power = int ; Power Level
SUIT_Wait_Event_Argument_Network = int ; Network State
SUIT_Wait_Event_Argument_Other_Device_Version = [
other-device: bstr,
other-device-version: [+int]
]
SUIT_Wait_Event_Argument_Time = uint ; Timestamp
SUIT_Wait_Event_Argument_Time_Of_Day = uint ; Time of Day
; (seconds since 00:00:00)
SUIT_Wait_Event_Argument_Day_Of_Week = uint ; Days since Sunday
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7.10.14. SUIT_Directive CDDL
The following CDDL describes SUIT_Directive:
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SUIT_Directive //= (suit-directive-set-component-index, uint/bool)
SUIT_Directive //= (suit-directive-set-dependency-index, uint/bool)
SUIT_Directive //= (suit-directive-run-sequence,
bstr .cbor SUIT_Command_Sequence)
SUIT_Directive //= (suit-directive-try-each,
SUIT_Directive_Try_Each_Argument)
SUIT_Directive //= (suit-directive-process-dependency, nil)
SUIT_Directive //= (suit-directive-set-parameters,
{+ SUIT_Parameters})
SUIT_Directive //= (suit-directive-override-parameters,
{+ SUIT_Parameters})
SUIT_Directive //= (suit-directive-fetch, nil)
SUIT_Directive //= (suit-directive-copy, nil)
SUIT_Directive //= (suit-directive-run, nil)
SUIT_Directive //= (suit-directive-wait,
{ + SUIT_Wait_Events })
SUIT_Directive //= (suit-directive-run-with-arguments, bstr)
SUIT_Directive_Try_Each_Argument = [
+ bstr .cbor SUIT_Command_Sequence,
nil / bstr .cbor SUIT_Command_Sequence
]
SUIT_Wait_Events //= (suit-wait-event-authorization => int)
SUIT_Wait_Events //= (suit-wait-event-power => int)
SUIT_Wait_Events //= (suit-wait-event-network => int)
SUIT_Wait_Events //= (suit-wait-event-other-device-version
=> SUIT_Wait_Event_Argument_Other_Device_Version)
SUIT_Wait_Events //= (suit-wait-event-time => uint); Timestamp
SUIT_Wait_Events //= (suit-wait-event-time-of-day
=> uint); Time of Day (seconds since 00:00:00)
SUIT_Wait_Events //= (suit-wait-event-day-of-week
=> uint); Days since Sunday
SUIT_Wait_Event_Argument_Authorization = int ; priority
SUIT_Wait_Event_Argument_Power = int ; Power Level
SUIT_Wait_Event_Argument_Network = int ; Network State
SUIT_Wait_Event_Argument_Other_Device_Version = [
other-device: bstr,
other-device-version: [+int]
]
SUIT_Wait_Event_Argument_Time = uint ; Timestamp
SUIT_Wait_Event_Argument_Time_Of_Day = uint ; Time of Day
; (seconds since 00:00:00)
SUIT_Wait_Event_Argument_Day_Of_Week = uint ; Days since Sunday
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7.11. SUIT_Text_Map
The SUIT_Text_Map contains all text descriptions needed for this
manifest. The text section is typically severable, allowing
manifests to be distributed without the text, since end-nodes do not
require text. The meaning of each field is described below.
Each section MAY be present. If present, each section MUST be as
described. Negative integer IDs are reserved for application-
specific text values.
+----+-----------------------+--------------------------------------+
| ID | Name | Summary |
+----+-----------------------+--------------------------------------+
| 1 | manifest-description | Free text description of the |
| | | manifest |
| | | |
| 2 | update-description | Free text description of the update |
| | | |
| 3 | vendor-name | Free text vendor name |
| | | |
| 4 | model-name | Free text model name |
| | | |
| 5 | vendor-domain | The domain used to create the |
| | | vendor-id (Section 7.9.9.1) |
| | | |
| 6 | model-info | The information used to create the |
| | | class-id (Section 7.9.9.1) |
| | | |
| 7 | component-description | Free text description of each |
| | | component in the manifest |
| | | |
| 8 | json-source | The JSON-formatted document that was |
| | | used to create the manifest |
| | | |
| 9 | yaml-source | The yaml-formatted document that was |
| | | used to create the manifest |
| | | |
| 10 | version-dependencies | List of component versions required |
| | | by the manifest |
+----+-----------------------+--------------------------------------+
8. Access Control Lists
To manage permissions in the manifest, there are three models that
can be used.
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First, the simplest model requires that all manifests are
authenticated by a single trusted key. This mode has the advantage
that only a root manifest needs to be authenticated, since all of its
dependencies have digests included in the root manifest.
This simplest model can be extended by adding key delegation without
much increase in complexity.
A second model requires an ACL to be presented to the device,
authenticated by a trusted party or stored on the device. This ACL
grants access rights for specific component IDs or component ID
prefixes to the listed identities or identity groups. Any identity
may verify an image digest, but fetching into or fetching from a
component ID requires approval from the ACL.
A third model allows a device to provide even more fine-grained
controls: The ACL lists the component ID or component ID prefix that
an identity may use, and also lists the commands that the identity
may use in combination with that component ID.
9. SUIT digest container
RFC 8152 [RFC8152] provides containers for signature, MAC, and
encryption, but no basic digest container. The container needed for
a digest requires a type identifier and a container for the raw
digest data. Some forms of digest may require additional parameters.
These can be added following the digest. This structure is described
by the following CDDL.
The algorithms listed are sufficient for verifying integrity of
Firmware Updates as of this writing, however this may change over
time.
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SUIT_Digest = [
suit-digest-algorithm-id : $suit-digest-algorithm-ids,
suit-digest-bytes : bytes,
? suit-digest-parameters : any
]
digest-algorithm-ids /= algorithm-id-sha224
digest-algorithm-ids /= algorithm-id-sha256
digest-algorithm-ids /= algorithm-id-sha384
digest-algorithm-ids /= algorithm-id-sha512
digest-algorithm-ids /= algorithm-id-sha3-224
digest-algorithm-ids /= algorithm-id-sha3-256
digest-algorithm-ids /= algorithm-id-sha3-384
digest-algorithm-ids /= algorithm-id-sha3-512
algorithm-id-sha224 = 1
algorithm-id-sha256 = 2
algorithm-id-sha384 = 3
algorithm-id-sha512 = 4
algorithm-id-sha3-224 = 5
algorithm-id-sha3-256 = 6
algorithm-id-sha3-384 = 7
algorithm-id-sha3-512 = 8
10. Creating Conditional Sequences
For some use cases, it is important to provide a sequence that can
fail without terminating an update. For example, a dual-image XIP
MCU may require an update that can be placed at one of two offsets.
This has two implications, first, the digest of each offset will be
different. Second, the image fetched for each offset will have a
different URI. Conditional sequences allow this to be resolved in a
simple way.
The following JSON representation of a manifest demonstrates how this
would be represented. It assumes that the bootloader and manifest
processor take care of A/B switching and that the manifest is not
aware of this distinction.
{
"structure-version" : 1,
"sequence-number" : 7,
"common" :{
"components" : [
[b'0']
],
"common-sequence" : [
{
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"directive-set-var" : {
"size": 32567
},
},
{
"try-each" : [
[
{"condition-component-offset" : "<offset A>"},
{
"directive-set-var": {
"digest" : "<SHA256 A>"
}
}
],
[
{"condition-component-offset" : "<offset B>"},
{
"directive-set-var": {
"digest" : "<SHA256 B>"
}
}
],
[{ "abort" : null }]
]
}
]
}
"fetch" : [
{
"try-each" : [
[
{"condition-component-offset" : "<offset A>"},
{
"directive-set-var": {
"uri" : "<URI A>"
}
}
],
[
{"condition-component-offset" : "<offset B>"},
{
"directive-set-var": {
"uri" : "<URI B>"
}
}
],
[{ "directive-abort" : null }]
]
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},
"fetch" : null
]
}
11. Full CDDL
In order to create a valid SUIT Manifest document the structure of
the corresponding CBOR message MUST adhere to the following CDDL data
definition.
SUIT_Outer_Wrapper = {
suit-delegation => bstr .cbor SUIT_Delegation
suit-authentication-wrapper
=> bstr .cbor SUIT_Authentication_Wrapper / nil,
$$SUIT_Manifest_Wrapped,
suit-dependency-resolution => bstr .cbor SUIT_Command_Sequence,
suit-payload-fetch => bstr .cbor SUIT_Command_Sequence,
suit-install => bstr .cbor SUIT_Command_Sequence,
suit-text => bstr .cbor SUIT_Text_Map,
suit-coswid => bstr .cbor concise-software-identity
}
SUIT_Authentication_Wrapper = [ + (
COSE_Mac_Tagged /
COSE_Sign_Tagged /
COSE_Mac0_Tagged /
COSE_Sign1_Tagged)
]
SUIT_Encryption_Wrapper = COSE_Encrypt_Tagged / COSE_Encrypt0_Tagged
$$SUIT_Manifest_Wrapped //= (suit-manifest => bstr .cbor SUIT_Manifest)
$$SUIT_Manifest_Wrapped //= (
suit-manifest-encryption-info => bstr .cbor SUIT_Encryption_Wrapper,
suit-manifest-encrypted => bstr
)
COSE_Mac_Tagged = any
COSE_Sign_Tagged = any
COSE_Mac0_Tagged = any
COSE_Sign1_Tagged = any
COSE_Encrypt_Tagged = any
COSE_Encrypt0_Tagged = any
SUIT_Digest = [
suit-digest-algorithm-id : $suit-digest-algorithm-ids,
suit-digest-bytes : bstr,
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? suit-digest-parameters : any
]
; Named Information Hash Algorithm Identifiers
suit-digest-algorithm-ids /= algorithm-id-sha224
suit-digest-algorithm-ids /= algorithm-id-sha256
suit-digest-algorithm-ids /= algorithm-id-sha384
suit-digest-algorithm-ids /= algorithm-id-sha512
suit-digest-algorithm-ids /= algorithm-id-sha3-224
suit-digest-algorithm-ids /= algorithm-id-sha3-256
suit-digest-algorithm-ids /= algorithm-id-sha3-384
suit-digest-algorithm-ids /= algorithm-id-sha3-512
algorithm-id-sha224 = 1
algorithm-id-sha256 = 2
algorithm-id-sha384 = 3
algorithm-id-sha512 = 4
algorithm-id-sha3-224 = 5
algorithm-id-sha3-256 = 6
algorithm-id-sha3-384 = 7
algorithm-id-sha3-512 = 8
SUIT_Manifest = {
suit-manifest-version => 1,
suit-manifest-sequence-number => uint,
? suit-common => bstr .cbor SUIT_Common,
? suit-dependency-resolution
=> SUIT_Digest / bstr .cbor SUIT_Command_Sequence,
? suit-payload-fetch
=> SUIT_Digest / bstr .cbor SUIT_Command_Sequence,
? suit-install
=> SUIT_Digest / bstr .cbor SUIT_Command_Sequence,
? suit-validate => bstr .cbor SUIT_Command_Sequence,
? suit-load => bstr .cbor SUIT_Command_Sequence,
? suit-run => bstr .cbor SUIT_Command_Sequence,
? suit-text => SUIT_Digest,
? suit-coswid
=> SUIT_Digest / bstr .cbor concise-software-identity,
}
SUIT_Common = {
? suit-dependencies => bstr .cbor SUIT_Dependencies,
? suit-components => bstr .cbor SUIT_Components,
? suit-dependency-components
=> bstr .cbor SUIT_Component_References,
? suit-common-sequence => bstr .cbor SUIT_Command_Sequence,
}
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SUIT_Dependencies = [ + SUIT_Dependency ]
SUIT_Components = [ + SUIT_Component_Identifier ]
SUIT_Component_References = [ + SUIT_Component_Reference ]
concise-software-identity = any
SUIT_Dependency = {
suit-dependency-digest => SUIT_Digest,
suit-dependency-prefix => SUIT_Component_Identifier,
}
SUIT_Component_Identifier = [* bstr]
SUIT_Component_Reference = {
suit-component-identifier => SUIT_Component_Identifier,
suit-component-dependency-index => uint
}
SUIT_Command_Sequence = [ + (
SUIT_Condition // SUIT_Directive // SUIT_Command_Custom
) ]
SUIT_Command_Custom = (nint, bstr)
SUIT_Condition //= (suit-condition-vendor-identifier, nil)
SUIT_Condition //= (suit-condition-class-identifier, nil)
SUIT_Condition //= (suit-condition-device-identifier, nil)
SUIT_Condition //= (suit-condition-image-match, nil)
SUIT_Condition //= (suit-condition-image-not-match, nil)
SUIT_Condition //= (suit-condition-use-before, uint)
SUIT_Condition //= (suit-condition-minimum-battery, uint)
SUIT_Condition //= (suit-condition-update-authorized, int)
SUIT_Condition //= (suit-condition-version,
SUIT_Condition_Version_Argument)
SUIT_Condition //= (suit-condition-component-offset, uint)
SUIT_Condition //= (suit-condition-custom, bstr)
RFC4122_UUID = bstr .size 16
SUIT_Condition_Version_Argument = [
suit-condition-version-comparison-type:
SUIT_Condition_Version_Comparison_Types,
suit-condition-version-comparison-value:
SUIT_Condition_Version_Comparison_Value
]
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater
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SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-greater-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser-equal
SUIT_Condition_Version_Comparison_Types /=
suit-condition-version-comparison-lesser
suit-condition-version-comparison-greater = 1
suit-condition-version-comparison-greater-equal = 2
suit-condition-version-comparison-equal = 3
suit-condition-version-comparison-lesser-equal = 4
suit-condition-version-comparison-lesser = 5
SUIT_Condition_Version_Comparison_Value = [+int]
SUIT_Directive //= (suit-directive-set-component-index, uint/bool)
SUIT_Directive //= (suit-directive-set-dependency-index, uint/bool)
SUIT_Directive //= (suit-directive-run-sequence,
bstr .cbor SUIT_Command_Sequence)
SUIT_Directive //= (suit-directive-try-each,
SUIT_Directive_Try_Each_Argument)
SUIT_Directive //= (suit-directive-process-dependency, nil)
SUIT_Directive //= (suit-directive-set-parameters,
{+ SUIT_Parameters})
SUIT_Directive //= (suit-directive-override-parameters,
{+ SUIT_Parameters})
SUIT_Directive //= (suit-directive-fetch, nil)
SUIT_Directive //= (suit-directive-copy, nil)
SUIT_Directive //= (suit-directive-swap, nil)
SUIT_Directive //= (suit-directive-run, nil)
SUIT_Directive //= (suit-directive-wait,
{ + SUIT_Wait_Events })
SUIT_Directive //= (suit-directive-run-with-arguments, bstr)
SUIT_Directive_Try_Each_Argument = [
+ bstr .cbor SUIT_Command_Sequence,
nil / bstr .cbor SUIT_Command_Sequence
]
SUIT_Wait_Events //= (suit-wait-event-authorization => int)
SUIT_Wait_Events //= (suit-wait-event-power => int)
SUIT_Wait_Events //= (suit-wait-event-network => int)
SUIT_Wait_Events //= (suit-wait-event-other-device-version
=> SUIT_Wait_Event_Argument_Other_Device_Version)
SUIT_Wait_Events //= (suit-wait-event-time => uint); Timestamp
SUIT_Wait_Events //= (suit-wait-event-time-of-day
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=> uint); Time of Day (seconds since 00:00:00)
SUIT_Wait_Events //= (suit-wait-event-day-of-week
=> uint); Days since Sunday
SUIT_Wait_Event_Argument_Authorization = int ; priority
SUIT_Wait_Event_Argument_Power = int ; Power Level
SUIT_Wait_Event_Argument_Network = int ; Network State
SUIT_Wait_Event_Argument_Other_Device_Version = [
other-device: bstr,
other-device-version: [+int]
]
SUIT_Wait_Event_Argument_Time = uint ; Timestamp
SUIT_Wait_Event_Argument_Time_Of_Day = uint ; Time of Day
; (seconds since 00:00:00)
SUIT_Wait_Event_Argument_Day_Of_Week = uint ; Days since Sunday
SUIT_Parameters //= (suit-parameter-strict-order => bool)
SUIT_Parameters //= (suit-parameter-soft-failure => bool)
SUIT_Parameters //= (suit-parameter-vendor-id => bstr)
SUIT_Parameters //= (suit-parameter-class-id => bstr)
SUIT_Parameters //= (suit-parameter-device-id => bstr)
SUIT_Parameters //= (suit-parameter-uri => tstr)
SUIT_Parameters //= (suit-parameter-encryption-info
=> bstr .cbor SUIT_Encryption_Info)
SUIT_Parameters //= (suit-parameter-compression-info
=> bstr .cbor SUIT_Compression_Info)
SUIT_Parameters //= (suit-parameter-unpack-info
=> bstr .cbor SUIT_Unpack_Info)
SUIT_Parameters //= (suit-parameter-source-component => uint)
SUIT_Parameters //= (suit-parameter-image-digest
=> bstr .cbor SUIT_Digest)
SUIT_Parameters //= (suit-parameter-image-size => uint)
SUIT_Parameters //= (suit-parameter-uri-list
=> bstr .cbor SUIT_Component_URI_List)
SUIT_Parameters //= (suit-parameter-custom => int/bool/tstr/bstr)
SUIT_Component_URI_List = [ + [priority: int, uri: tstr] ]
SUIT_Encryption_Info = COSE_Encrypt_Tagged/COSE_Encrypt0_Tagged
SUIT_Compression_Info = {
suit-compression-algorithm => SUIT_Compression_Algorithms,
? suit-compression-parameters => bstr
}
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_gzip
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_bzip2
SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_lz4
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SUIT_Compression_Algorithms /= SUIT_Compression_Algorithm_lzma
SUIT_Compression_Algorithm_gzip = 1
SUIT_Compression_Algorithm_bzip2 = 2
SUIT_Compression_Algorithm_deflate = 3
SUIT_Compression_Algorithm_lz4 = 4
SUIT_Compression_Algorithm_lzma = 7
SUIT_Unpack_Info = {
suit-unpack-algorithm => SUIT_Unpack_Algorithms,
? suit-unpack-parameters => bstr
}
SUIT_Unpack_Algorithms /= SUIT_Unpack_Algorithm_Delta
SUIT_Unpack_Algorithms /= SUIT_Unpack_Algorithm_Hex
SUIT_Unpack_Algorithms /= SUIT_Unpack_Algorithm_Elf
SUIT_Unpack_Algorithm_Delta = 1
SUIT_Unpack_Algorithm_Hex = 2
SUIT_Unpack_Algorithm_Elf = 3
SUIT_Text_Map = {int => tstr}
suit-authentication-wrapper = 1
suit-manifest = 2
suit-manifest-encryption-info = 3
suit-manifest-encrypted = 4
suit-manifest-version = 1
suit-manifest-sequence-number = 2
suit-common = 3
suit-dependency-resolution = 7
suit-payload-fetch = 8
suit-install = 9
suit-validate = 10
suit-load = 11
suit-run = 12
suit-text = 13
suit-coswid = 14
suit-dependencies = 1
suit-components = 2
suit-dependency-components = 3
suit-common-sequence = 4
suit-dependency-digest = 1
suit-dependency-prefix = 2
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suit-component-identifier = 1
suit-component-dependency-index = 2
suit-command-custom = nint
suit-condition-vendor-identifier = 1
suit-condition-class-identifier = 2
suit-condition-image-match = 3
suit-condition-use-before = 4
suit-condition-component-offset = 5
suit-condition-custom = 6
suit-condition-device-identifier = 24
suit-condition-image-not-match = 25
suit-condition-minimum-battery = 26
suit-condition-update-authorized = 27
suit-condition-version = 28
suit-directive-set-component-index = 12
suit-directive-set-dependency-index = 13
suit-directive-abort = 14
suit-directive-try-each = 15
;suit-directive-do-each = 16 ; TBD
;suit-directive-map-filter = 17 ; TBD
suit-directive-process-dependency = 18
suit-directive-set-parameters = 19
suit-directive-override-parameters = 20
suit-directive-fetch = 21
suit-directive-copy = 22
suit-directive-run = 23
suit-directive-wait = 29
suit-directive-run-sequence = 30
suit-directive-run-with-arguments = 31
suit-directive-swap = 32
suit-wait-event-argument-authorization = 1
suit-wait-event-power = 2
suit-wait-event-network = 3
suit-wait-event-other-device-version = 4
suit-wait-event-time = 5
suit-wait-event-time-of-day = 6
suit-wait-event-day-of-week = 7
suit-wait-event-authorization = 8
suit-parameter-strict-order = 1
suit-parameter-soft-failure = 2
suit-parameter-vendor-id = 3
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suit-parameter-class-id = 4
suit-parameter-device-id = 5
suit-parameter-uri = 6
suit-parameter-encryption-info = 7
suit-parameter-compression-info = 8
suit-parameter-unpack-info = 9
suit-parameter-source-component = 10
suit-parameter-image-digest = 11
suit-parameter-image-size = 12
suit-parameter-uri-list = 24
suit-parameter-uri-list-append = 25
suit-parameter-prioritized-parameters = 26
suit-parameter-custom = nint
suit-compression-algorithm = 1
suit-compression-parameters = 2
suit-unpack-algorithm = 1
suit-unpack-parameters = 2
suit-text-manifest-description = 1
suit-text-update-description = 2
suit-text-vendor-name = 3
suit-text-model-name = 4
suit-text-vendor-domain = 5
suit-text-model-info = 6
suit-text-component-description = 7
suit-text-manifest-json-source = 8
suit-text-manifest-yaml-source = 9
suit-text-version-dependencies = 10
12. Examples
The following examples demonstrate a small subset of the
functionality of the manifest. However, despite this, even a simple
manifest processor can execute most of these manifests.
The examples are signed using the following ECDSA secp256r1 key:
-----BEGIN PRIVATE KEY-----
MIGHAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBG0wawIBAQQgApZYjZCUGLM50VBC
CjYStX+09jGmnyJPrpDLTz/hiXOhRANCAASEloEarguqq9JhVxie7NomvqqL8Rtv
P+bitWWchdvArTsfKktsCYExwKNtrNHXi9OB3N+wnAUtszmR23M4tKiW
-----END PRIVATE KEY-----
The corresponding public key can be used to verify these examples:
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-----BEGIN PUBLIC KEY-----
MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEhJaBGq4LqqvSYVcYnuzaJr6qi/Eb
bz/m4rVlnIXbwK07HypLbAmBMcCjbazR14vTgdzfsJwFLbM5kdtzOLSolg==
-----END PUBLIC KEY-----
12.1. Example 0: Secure Boot
Secure boot and compatibility check.
{
/ authentication-wrapper / 2:h'81d28443a10126a058248202582073054c8
cc42e3e76c974ad0bed685d88b0b99df40fbaf72f58cd0b97dcd03285584057bc22b81
43137abb3e8dc180a74348b58905d36ac16c199443cd1d09214a68bd4acdbbde78a521
7768faa00627a0a92da30f36bd2187f77ba14b16b0637c618' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
/ payload / h'8202582073054c8cc42e3e76c974ad0bed685d88
b0b99df40fbaf72f58cd0b97dcd03285' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'73054c8cc42e3e76c974ad0bed685d88b0b99df40fbaf72f58cd0b97dcd03285'
] /,
/ signature / h'57bc22b8143137abb3e8dc180a74348b58905d
36ac16c199443cd1d09214a68bd4acdbbde78a5217768faa00627a0a92da30f36bd218
7f77ba14b16b0637c618'
])
] /,
/ manifest / 3:h'a50101020103585aa2024481814100045850860150fa6b4a5
3d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b820
2582000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100
c1987d00a438203f60c438217f6' / {
/ manifest-version / 1:1,
/ manifest-sequence-number / 2:1,
/ common / 3:h'a2024481814100045850860150fa6b4a53d5ad5fdfbe9de
663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334
45566778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / {
/ components / 2:h'81814100' / [
[h'00']
] /,
/ common-sequence / 4:h'860150fa6b4a53d5ad5fdfbe9de663e4d4
1ffe02501492af1425695e48bf429b2d51f2ab4514a20b820258200011223344556677
8899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [
/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
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be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
}
] /,
} /,
/ validate / 10:h'8203f6' / [
/ condition-image-match / 3,F6 / nil /
] /,
/ run / 12:h'8217f6' / [
/ directive-run / 23,None
] /,
} /,
}
Total size of manifest without COSE authentication object: 112
Manifest:
a103586ca50101020103585aa2024481814100045850860150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d00a438203f60c438217f6
Total size of manifest with COSE authentication object: 227
Manifest with COSE authentication object:
a202587081d28443a10126a058248202582073054c8cc42e3e76c974ad0b
ed685d88b0b99df40fbaf72f58cd0b97dcd03285584057bc22b8143137ab
b3e8dc180a74348b58905d36ac16c199443cd1d09214a68bd4acdbbde78a
5217768faa00627a0a92da30f36bd2187f77ba14b16b0637c61803586ca5
0101020103585aa2024481814100045850860150fa6b4a53d5ad5fdfbe9d
e663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b820258
2000112233445566778899aabbccddeeff0123456789abcdeffedcba9876
5432100c1987d00a438203f60c438217f6
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12.2. Example 1: Simultaneous Download and Installation of Payload
Simultaneous download and installation of payload.
{
/ authentication-wrapper / 2:h'81d28443a10126a0582482025820be9d3da
5d45b780bcaeb84a909b54913302a358d9d7dc6b94c7fbb1f56dbf5f95840d89fb4194
4231adb3920bdae14a4965699771b50e062c28ffef93400a9b63150902bc65929e8066
e1a0eb45be50ee96db0435e5c141ae8fb94cbf2b37205ba6b' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
/ payload / h'82025820be9d3da5d45b780bcaeb84a909b54913
302a358d9d7dc6b94c7fbb1f56dbf5f9' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'be9d3da5d45b780bcaeb84a909b54913302a358d9d7dc6b94c7fbb1f56dbf5f9'
] /,
/ signature / h'd89fb41944231adb3920bdae14a4965699771b
50e062c28ffef93400a9b63150902bc65929e8066e1a0eb45be50ee96db0435e5c141a
e8fb94cbf2b37205ba6b'
])
] /,
/ manifest / 3:h'a40101020203585aa2024481814100045850860150fa6b4a5
3d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b820
2582000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100
c1987d00958258613a106781b687474703a2f2f6578616d706c652e636f6d2f66696c6
52e62696e15f603f6' / {
/ manifest-version / 1:1,
/ manifest-sequence-number / 2:2,
/ common / 3:h'a2024481814100045850860150fa6b4a53d5ad5fdfbe9de
663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334
45566778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / {
/ components / 2:h'81814100' / [
[h'00']
] /,
/ common-sequence / 4:h'860150fa6b4a53d5ad5fdfbe9de663e4d4
1ffe02501492af1425695e48bf429b2d51f2ab4514a20b820258200011223344556677
8899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [
/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
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/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
}
] /,
} /,
/ install / 9:h'8613a106781b687474703a2f2f6578616d706c652e636f
6d2f66696c652e62696e15f603f6' / [
/ directive-set-parameters / 19,{
/ uri / 6:'http://example.com/file.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil /
] /,
} /,
}
Total size of manifest without COSE authentication object: 142
Manifest:
a103588aa40101020203585aa2024481814100045850860150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d00958258613a106781b687474703a2f2f6578
616d706c652e636f6d2f66696c652e62696e15f603f6
Total size of manifest with COSE authentication object: 257
Manifest with COSE authentication object: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12.3. Example 2: Simultaneous Download, Installation, and Secure Boot
Compatibility test, simultaneous download and installation, and
secure boot. ~~~ { / authentication-wrapper /
2:h'81d28443a10126a058248202582070cf2a4 fed640658ada6ff33b59af192ca22
b4142e9ae9d8d9b05f2b5a118cf35840f6c95681e f4298dc1288e11004a4b72be80a
374be13efccf5ec94fa1ad2ca7d5510d5ff43ceac60
e7dd32d3614bd0350768f985eff8ba9933625d206286cf983' / [ 18([ /
protected / h'a10126' / { / alg / 1:-7 / ES256 /, } /, / unprotected
/ { }, / payload / h'8202582070cf2a4fed640658ada6ff33b59af192
ca22b4142e9ae9d8d9b05f2b5a118cf3' / [ / algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'70cf2a4fed640658ada6ff33b59af192ca22b4142e9ae9d8d9b05f2b5a118cf3' ]
/, / signature / h'f6c95681ef4298dc1288e11004a4b72be80a37 4be13efccf5
ec94fa1ad2ca7d5510d5ff43ceac60e7dd32d3614bd0350768f985eff8b
a9933625d206286cf983' ]) ] /, / manifest /
3:h'a60101020303585aa2024481814100045850860150fa6b4a5 3d5ad5fdfbe9de6
63e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b820 2582000112233
445566778899aabbccddeeff0123456789abcdeffedcba98765432100 c1987d00958
258613a106781b687474703a2f2f6578616d706c652e636f6d2f66696c6
52e62696e15f603f60a438203f60c438217f6' / { / manifest-version / 1:1,
/ manifest-sequence-number / 2:3, / common /
3:h'a2024481814100045850860150fa6b4a53d5ad5fdfbe9de 663e4d41ffe025014
92af1425695e48bf429b2d51f2ab4514a20b82025820001122334
45566778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / {
/ components / 2:h'81814100' / [ [h'00'] ] /, / common-sequence /
4:h'860150fa6b4a53d5ad5fdfbe9de663e4d4 1ffe02501492af1425695e48bf429b
2d51f2ab4514a20b820258200011223344556677
8899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [ /
condition-vendor-identifier / 1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' /
fa6b4a53-d5ad-5fdf- be9d-e663e4d41ffe / , / condition-class-
identifier / 2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / , / directive-override-
parameters / 20,{ / image-digest / 11:[ / algorithm-id / 2 / sha256
/, / digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
], / image-size / 12:34768, } ] /, } /, / install /
9:h'8613a106781b687474703a2f2f6578616d706c652e636f
6d2f66696c652e62696e15f603f6' / [ / directive-set-parameters / 19,{ /
uri / 6:'http://example.com/file.bin', } , / directive-fetch / 21,F6
/ nil / , / condition-image-match / 3,F6 / nil / ] /, / validate /
10:h'8203f6' / [ / condition-image-match / 3,F6 / nil / ] /, / run /
12:h'8217f6' / [ / directive-run / 23,None ] /, } /, } ~~~
Total size of manifest without COSE authentication object: 152
Manifest:
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a1035894a60101020303585aa2024481814100045850860150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d00958258613a106781b687474703a2f2f6578
616d706c652e636f6d2f66696c652e62696e15f603f60a438203f60c4382
17f6
Total size of manifest with COSE authentication object: 267
Manifest with COSE authentication object:
a202587081d28443a10126a058248202582070cf2a4fed640658ada6ff33
b59af192ca22b4142e9ae9d8d9b05f2b5a118cf35840f6c95681ef4298dc
1288e11004a4b72be80a374be13efccf5ec94fa1ad2ca7d5510d5ff43cea
c60e7dd32d3614bd0350768f985eff8ba9933625d206286cf983035894a6
0101020303585aa2024481814100045850860150fa6b4a53d5ad5fdfbe9d
e663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b820258
2000112233445566778899aabbccddeeff0123456789abcdeffedcba9876
5432100c1987d00958258613a106781b687474703a2f2f6578616d706c65
2e636f6d2f66696c652e62696e15f603f60a438203f60c438217f6
12.4. Example 3: Load from External Storage
Compatibility test, simultaneous download and installation, load from
external storage, and secure boot.
{
/ authentication-wrapper / 2:h'81d28443a10126a0582482025820bb008f5
7fd1babff8cc432d18c4c9cfc69d7e8ab76b07cc910c6d03ec598baab58409e98c58fc
d82668443a0249fa5eab10474a099572dfb31c0d2adf750f57c4987d484badf8524a20
a9e92c4599698eb696254d4c0f77947c8af353b544600ea11' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
/ payload / h'82025820bb008f57fd1babff8cc432d18c4c9cfc
69d7e8ab76b07cc910c6d03ec598baab' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'bb008f57fd1babff8cc432d18c4c9cfc69d7e8ab76b07cc910c6d03ec598baab'
] /,
/ signature / h'9e98c58fcd82668443a0249fa5eab10474a099
572dfb31c0d2adf750f57c4987d484badf8524a20a9e92c4599698eb696254d4c0f779
47c8af353b544600ea11'
])
] /,
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/ manifest / 3:h'a70101020403585fa2024782814100814101045852880c000
150fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4
514a20b8202582000112233445566778899aabbccddeeff0123456789abcdeffedcba9
8765432100c1987d0095827880c0013a106781b687474703a2f2f6578616d706c652e6
36f6d2f66696c652e62696e15f603f60a45840c0003f60b5834880c0114a30a000b820
2582000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100
c1987d016f603f60c45840c0117f6' / {
/ manifest-version / 1:1,
/ manifest-sequence-number / 2:4,
/ common / 3:h'a2024782814100814101045852880c000150fa6b4a53d5a
d5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b8202582
000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100c198
7d0' / {
/ components / 2:h'82814100814101' / [
[h'00'] ,
[h'01']
] /,
/ common-sequence / 4:h'880c000150fa6b4a53d5ad5fdfbe9de663
e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334455
66778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [
/ directive-set-component-index / 12,0 ,
/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
}
] /,
} /,
/ install / 9:h'880c0013a106781b687474703a2f2f6578616d706c652e
636f6d2f66696c652e62696e15f603f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-set-parameters / 19,{
/ uri / 6:'http://example.com/file.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil /
] /,
/ validate / 10:h'840c0003f6' / [
/ directive-set-component-index / 12,0 ,
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/ condition-image-match / 3,F6 / nil /
] /,
/ load / 11:h'880c0114a30a000b8202582000112233445566778899aabb
ccddeeff0123456789abcdeffedcba98765432100c1987d016f603f6' / [
/ directive-set-component-index / 12,1 ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
/ source-component / 10:0 / [h'00'] /,
} ,
/ directive-copy / 22,None ,
/ condition-image-match / 3,F6 / nil /
] /,
/ run / 12:h'840c0117f6' / [
/ directive-set-component-index / 12,1 ,
/ directive-run / 23,None
] /,
} /,
}
Total size of manifest without COSE authentication object: 218
Manifest:
a10358d6a70101020403585fa2024782814100814101045852880c000150
fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d
51f2ab4514a20b8202582000112233445566778899aabbccddeeff012345
6789abcdeffedcba98765432100c1987d0095827880c0013a106781b6874
74703a2f2f6578616d706c652e636f6d2f66696c652e62696e15f603f60a
45840c0003f60b5834880c0114a30a000b82025820001122334455667788
99aabbccddeeff0123456789abcdeffedcba98765432100c1987d016f603
f60c45840c0117f6
Total size of manifest with COSE authentication object: 333
Manifest with COSE authentication object:
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a202587081d28443a10126a0582482025820bb008f57fd1babff8cc432d1
8c4c9cfc69d7e8ab76b07cc910c6d03ec598baab58409e98c58fcd826684
43a0249fa5eab10474a099572dfb31c0d2adf750f57c4987d484badf8524
a20a9e92c4599698eb696254d4c0f77947c8af353b544600ea110358d6a7
0101020403585fa2024782814100814101045852880c000150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d0095827880c0013a106781b687474703a2f2f
6578616d706c652e636f6d2f66696c652e62696e15f603f60a45840c0003
f60b5834880c0114a30a000b8202582000112233445566778899aabbccdd
eeff0123456789abcdeffedcba98765432100c1987d016f603f60c45840c
0117f6
12.5. Example 4: Load and Decompress from External Storage
Compatibility test, simultaneous download and installation, load and
decompress from external storage, and secure boot.
{
/ authentication-wrapper / 2:h'81d28443a10126a0582482025820b973e24
24d03de20c59cb702607a83796dd465674115ae84b3c2c472794dbb8c5840be0ae3d36
0e46dd07f02547ff19e4a1557b7bfce401718ade8200918f191a50dca84148704f76d9
7a8c239615114eab0617e9fc9d4faeac1572e7cae61e660c1' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
/ payload / h'82025820b973e2424d03de20c59cb702607a8379
6dd465674115ae84b3c2c472794dbb8c' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'b973e2424d03de20c59cb702607a83796dd465674115ae84b3c2c472794dbb8c'
] /,
/ signature / h'be0ae3d360e46dd07f02547ff19e4a1557b7bf
ce401718ade8200918f191a50dca84148704f76d97a8c239615114eab0617e9fc9d4fa
eac1572e7cae61e660c1'
])
] /,
/ manifest / 3:h'a70101020503585fa2024782814100814101045852880c000
150fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4
514a20b8202582000112233445566778899aabbccddeeff0123456789abcdeffedcba9
8765432100c1987d0095827880c0013a106781b687474703a2f2f6578616d706c652e6
36f6d2f66696c652e62696e15f603f60a45840c0003f60b5836880c0114a408010a000
b8202582000112233445566778899aabbccddeeff0123456789abcdeffedcba9876543
2100c1987d016f603f60c45840c0117f6' / {
/ manifest-version / 1:1,
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/ manifest-sequence-number / 2:5,
/ common / 3:h'a2024782814100814101045852880c000150fa6b4a53d5a
d5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b8202582
000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100c198
7d0' / {
/ components / 2:h'82814100814101' / [
[h'00'] ,
[h'01']
] /,
/ common-sequence / 4:h'880c000150fa6b4a53d5ad5fdfbe9de663
e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334455
66778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [
/ directive-set-component-index / 12,0 ,
/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
}
] /,
} /,
/ install / 9:h'880c0013a106781b687474703a2f2f6578616d706c652e
636f6d2f66696c652e62696e15f603f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-set-parameters / 19,{
/ uri / 6:'http://example.com/file.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil /
] /,
/ validate / 10:h'840c0003f6' / [
/ directive-set-component-index / 12,0 ,
/ condition-image-match / 3,F6 / nil /
] /,
/ load / 11:h'880c0114a408010a000b8202582000112233445566778899
aabbccddeeff0123456789abcdeffedcba98765432100c1987d016f603f6' / [
/ directive-set-component-index / 12,1 ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
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/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
/ source-component / 10:0 / [h'00'] /,
/ compression-info / 8:1 / gzip /,
} ,
/ directive-copy / 22,None ,
/ condition-image-match / 3,F6 / nil /
] /,
/ run / 12:h'840c0117f6' / [
/ directive-set-component-index / 12,1 ,
/ directive-run / 23,None
] /,
} /,
}
Total size of manifest without COSE authentication object: 220
Manifest:
a10358d8a70101020503585fa2024782814100814101045852880c000150
fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d
51f2ab4514a20b8202582000112233445566778899aabbccddeeff012345
6789abcdeffedcba98765432100c1987d0095827880c0013a106781b6874
74703a2f2f6578616d706c652e636f6d2f66696c652e62696e15f603f60a
45840c0003f60b5836880c0114a408010a000b8202582000112233445566
778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d016
f603f60c45840c0117f6
Total size of manifest with COSE authentication object: 335
Manifest with COSE authentication object:
a202587081d28443a10126a0582482025820b973e2424d03de20c59cb702
607a83796dd465674115ae84b3c2c472794dbb8c5840be0ae3d360e46dd0
7f02547ff19e4a1557b7bfce401718ade8200918f191a50dca84148704f7
6d97a8c239615114eab0617e9fc9d4faeac1572e7cae61e660c10358d8a7
0101020503585fa2024782814100814101045852880c000150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d0095827880c0013a106781b687474703a2f2f
6578616d706c652e636f6d2f66696c652e62696e15f603f60a45840c0003
f60b5836880c0114a408010a000b8202582000112233445566778899aabb
ccddeeff0123456789abcdeffedcba98765432100c1987d016f603f60c45
840c0117f6
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12.6. Example 5: Compatibility Test, Download, Installation, and Secure
Boot
Compatibility test, download, installation, and secure boot.
{
/ authentication-wrapper / 2:h'81d28443a10126a05824820258207f35fdc
e6a55bed88d04497d38b7c2b4ffd1ddb74a83d9acd252d2077637de7058407bec97551
827d684ac07b77c3f663f4f9436aff0b79fdfd89061bfe9bddb73919c88d32dc52fd9e
b1d1ea34172eef5c222e7d897778c6b0254e20c7e87942ae1' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
/ payload / h'820258207f35fdce6a55bed88d04497d38b7c2b4
ffd1ddb74a83d9acd252d2077637de70' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'7f35fdce6a55bed88d04497d38b7c2b4ffd1ddb74a83d9acd252d2077637de70'
] /,
/ signature / h'7bec97551827d684ac07b77c3f663f4f9436af
f0b79fdfd89061bfe9bddb73919c88d32dc52fd9eb1d1ea34172eef5c222e7d897778c
6b0254e20c7e87942ae1'
])
] /,
/ manifest / 3:h'a70101020503585fa2024782814100814101045852880c000
150fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4
514a20b8202582000112233445566778899aabbccddeeff0123456789abcdeffedcba9
8765432100c1987d008584c880c0113a206781b687474703a2f2f6578616d706c652e6
36f6d2f66696c652e62696e0b8202582000112233445566778899aabbccddeeff01234
56789abcdeffedcba987654321015f603f6094d8a0c0013a10a0116f60c0103f60a458
40c0003f60c45840c0017f6' / {
/ manifest-version / 1:1,
/ manifest-sequence-number / 2:5,
/ common / 3:h'a2024782814100814101045852880c000150fa6b4a53d5a
d5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b8202582
000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100c198
7d0' / {
/ components / 2:h'82814100814101' / [
[h'00'] ,
[h'01']
] /,
/ common-sequence / 4:h'880c000150fa6b4a53d5ad5fdfbe9de663
e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334455
66778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d0' / [
/ directive-set-component-index / 12,0 ,
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/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ image-size / 12:34768,
}
] /,
} /,
/ payload-fetch / 8:h'880c0113a206781b687474703a2f2f6578616d70
6c652e636f6d2f66696c652e62696e0b8202582000112233445566778899aabbccddee
ff0123456789abcdeffedcba987654321015f603f6' / [
/ directive-set-component-index / 12,1 ,
/ directive-set-parameters / 19,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
/ uri / 6:'http://example.com/file.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil /
] /,
/ install / 9:h'8a0c0013a10a0116f60c0103f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-set-parameters / 19,{
/ source-component / 10:1 / [h'01'] /,
} ,
/ directive-copy / 22,None ,
/ directive-set-component-index / 12,1 ,
/ condition-image-match / 3,F6 / nil /
] /,
/ validate / 10:h'840c0003f6' / [
/ directive-set-component-index / 12,0 ,
/ condition-image-match / 3,F6 / nil /
] /,
/ run / 12:h'840c0017f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-run / 23,None
] /,
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} /,
}
Total size of manifest without COSE authentication object: 215
Manifest:
a10358d3a70101020503585fa2024782814100814101045852880c000150
fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d
51f2ab4514a20b8202582000112233445566778899aabbccddeeff012345
6789abcdeffedcba98765432100c1987d008584c880c0113a206781b6874
74703a2f2f6578616d706c652e636f6d2f66696c652e62696e0b82025820
00112233445566778899aabbccddeeff0123456789abcdeffedcba987654
321015f603f6094d8a0c0013a10a0116f60c0103f60a45840c0003f60c45
840c0017f6
Total size of manifest with COSE authentication object: 330
Manifest with COSE authentication object:
a202587081d28443a10126a05824820258207f35fdce6a55bed88d04497d
38b7c2b4ffd1ddb74a83d9acd252d2077637de7058407bec97551827d684
ac07b77c3f663f4f9436aff0b79fdfd89061bfe9bddb73919c88d32dc52f
d9eb1d1ea34172eef5c222e7d897778c6b0254e20c7e87942ae10358d3a7
0101020503585fa2024782814100814101045852880c000150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d008584c880c0113a206781b687474703a2f2f
6578616d706c652e636f6d2f66696c652e62696e0b820258200011223344
5566778899aabbccddeeff0123456789abcdeffedcba987654321015f603
f6094d8a0c0013a10a0116f60c0103f60a45840c0003f60c45840c0017f6
12.7. Example 6: Two Images
Compatibility test, 2 images, simultaneous download and installation,
and secure boot.
{
/ authentication-wrapper / 2:h'81d28443a10126a058248202582007954f5
19cdd8101156768fbe12f23eb5ca73481e91ca4801bf94dc82f52b0ea5840a76e7f712
b8d3ed6bcf79eaef8f15ee76f8da15aa16b220431f528d5cc237f95688748a156c8ee8
47c517b0c660328a7877be52b1902f50e7acecc4bbd6c439f' / [
18([
/ protected / h'a10126' / {
/ alg / 1:-7 / ES256 /,
} /,
/ unprotected / {
},
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/ payload / h'8202582007954f519cdd8101156768fbe12f23eb
5ca73481e91ca4801bf94dc82f52b0ea' / [
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'07954f519cdd8101156768fbe12f23eb5ca73481e91ca4801bf94dc82f52b0ea'
] /,
/ signature / h'a76e7f712b8d3ed6bcf79eaef8f15ee76f8da1
5aa16b220431f528d5cc237f95688748a156c8ee847c517b0c660328a7877be52b1902
f50e7acecc4bbd6c439f'
])
] /,
/ manifest / 3:h'a60101020303588ea20247828141008141010458818c0c000
150fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4
514a20b8202582000112233445566778899aabbccddeeff0123456789abcdeffedcba9
8765432100c1987d00c0114a20b820258200123456789abcdeffedcba9876543210001
12233445566778899aabbccddeeff0c1a00012c2209584f900c0013a106781c6874747
03a2f2f6578616d706c652e636f6d2f66696c65312e62696e15f603f60c0113a106781
c687474703a2f2f6578616d706c652e636f6d2f66696c65322e62696e15f603f60a498
80c0003f60c0103f60c45840c0017f6' / {
/ manifest-version / 1:1,
/ manifest-sequence-number / 2:3,
/ common / 3:h'a20247828141008141010458818c0c000150fa6b4a53d5a
d5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b8202582
000112233445566778899aabbccddeeff0123456789abcdeffedcba98765432100c198
7d00c0114a20b820258200123456789abcdeffedcba987654321000112233445566778
899aabbccddeeff0c1a00012c22' / {
/ components / 2:h'82814100814101' / [
[h'00'] ,
[h'01']
] /,
/ common-sequence / 4:h'8c0c000150fa6b4a53d5ad5fdfbe9de663
e4d41ffe02501492af1425695e48bf429b2d51f2ab4514a20b82025820001122334455
66778899aabbccddeeff0123456789abcdeffedcba98765432100c1987d00c0114a20b
820258200123456789abcdeffedcba987654321000112233445566778899aabbccddee
ff0c1a00012c22' / [
/ directive-set-component-index / 12,0 ,
/ condition-vendor-identifier /
1,h'fa6b4a53d5ad5fdfbe9de663e4d41ffe' / fa6b4a53-d5ad-5fdf-
be9d-e663e4d41ffe / ,
/ condition-class-identifier /
2,h'1492af1425695e48bf429b2d51f2ab45' /
1492af14-2569-5e48-bf42-9b2d51f2ab45 / ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'00112233445566778899aabbccddeeff0123456789abcdeffedcba9876543210'
],
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/ image-size / 12:34768,
} ,
/ directive-set-component-index / 12,1 ,
/ directive-override-parameters / 20,{
/ image-digest / 11:[
/ algorithm-id / 2 / sha256 /,
/ digest-bytes /
h'0123456789abcdeffedcba987654321000112233445566778899aabbccddeeff'
],
/ image-size / 12:76834,
}
] /,
} /,
/ install / 9:h'900c0013a106781c687474703a2f2f6578616d706c652e
636f6d2f66696c65312e62696e15f603f60c0113a106781c687474703a2f2f6578616d
706c652e636f6d2f66696c65322e62696e15f603f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-set-parameters / 19,{
/ uri / 6:'http://example.com/file1.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil / ,
/ directive-set-component-index / 12,1 ,
/ directive-set-parameters / 19,{
/ uri / 6:'http://example.com/file2.bin',
} ,
/ directive-fetch / 21,F6 / nil / ,
/ condition-image-match / 3,F6 / nil /
] /,
/ validate / 10:h'880c0003f60c0103f6' / [
/ directive-set-component-index / 12,0 ,
/ condition-image-match / 3,F6 / nil / ,
/ directive-set-component-index / 12,1 ,
/ condition-image-match / 3,F6 / nil /
] /,
/ run / 12:h'840c0017f6' / [
/ directive-set-component-index / 12,0 ,
/ directive-run / 23,None
] /,
} /,
}
Total size of manifest without COSE authentication object: 254
Manifest:
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a10358faa60101020303588ea20247828141008141010458818c0c000150
fa6b4a53d5ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d
51f2ab4514a20b8202582000112233445566778899aabbccddeeff012345
6789abcdeffedcba98765432100c1987d00c0114a20b8202582001234567
89abcdeffedcba987654321000112233445566778899aabbccddeeff0c1a
00012c2209584f900c0013a106781c687474703a2f2f6578616d706c652e
636f6d2f66696c65312e62696e15f603f60c0113a106781c687474703a2f
2f6578616d706c652e636f6d2f66696c65322e62696e15f603f60a49880c
0003f60c0103f60c45840c0017f6
Total size of manifest with COSE authentication object: 369
Manifest with COSE authentication object:
a202587081d28443a10126a058248202582007954f519cdd8101156768fb
e12f23eb5ca73481e91ca4801bf94dc82f52b0ea5840a76e7f712b8d3ed6
bcf79eaef8f15ee76f8da15aa16b220431f528d5cc237f95688748a156c8
ee847c517b0c660328a7877be52b1902f50e7acecc4bbd6c439f0358faa6
0101020303588ea20247828141008141010458818c0c000150fa6b4a53d5
ad5fdfbe9de663e4d41ffe02501492af1425695e48bf429b2d51f2ab4514
a20b8202582000112233445566778899aabbccddeeff0123456789abcdef
fedcba98765432100c1987d00c0114a20b820258200123456789abcdeffe
dcba987654321000112233445566778899aabbccddeeff0c1a00012c2209
584f900c0013a106781c687474703a2f2f6578616d706c652e636f6d2f66
696c65312e62696e15f603f60c0113a106781c687474703a2f2f6578616d
706c652e636f6d2f66696c65322e62696e15f603f60a49880c0003f60c01
03f60c45840c0017f6
13. IANA Considerations
Several registries will be required for:
- standard Commands.
- standard Parameters.
- standard Algorithm identifiers.
- standard text values.
14. Security Considerations
This document is about a manifest format describing and protecting
firmware images and as such it is part of a larger solution for
offering a standardized way of delivering firmware updates to IoT
devices. A more detailed discussion about security can be found in
the architecture document [I-D.ietf-suit-architecture] and in
[I-D.ietf-suit-information-model].
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15. Mailing List Information
The discussion list for this document is located at the e-mail
address suit@ietf.org [1]. Information on the group and information
on how to subscribe to the list is at
https://www1.ietf.org/mailman/listinfo/suit [2]
Archives of the list can be found at: https://www.ietf.org/mail-
archive/web/suit/current/index.html [3]
16. Acknowledgements
We would like to thank the following persons for their support in
designing this mechanism:
- Milosch Meriac
- Geraint Luff
- Dan Ros
- John-Paul Stanford
- Hugo Vincent
- Carsten Bormann
- Oeyvind Roenningstad
- Frank Audun Kvamtroe
- Krzysztof Chruściński
- Andrzej Puzdrowski
- Michael Richardson
- David Brown
- Emmanuel Baccelli
17. References
17.1. Normative References
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[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>.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
DOI 10.17487/RFC4122, July 2005,
<https://www.rfc-editor.org/info/rfc4122>.
[RFC8152] Schaad, J., "CBOR Object Signing and Encryption (COSE)",
RFC 8152, DOI 10.17487/RFC8152, July 2017,
<https://www.rfc-editor.org/info/rfc8152>.
[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>.
17.2. Informative References
[I-D.ietf-suit-architecture]
Moran, B., Tschofenig, H., Brown, D., and M. Meriac, "A
Firmware Update Architecture for Internet of Things",
draft-ietf-suit-architecture-08 (work in progress),
November 2019.
[I-D.ietf-suit-information-model]
Moran, B., Tschofenig, H., and H. Birkholz, "An
Information Model for Firmware Updates in IoT Devices",
draft-ietf-suit-information-model-05 (work in progress),
January 2020.
17.3. URIs
[1] mailto:suit@ietf.org
[2] https://www1.ietf.org/mailman/listinfo/suit
[3] https://www.ietf.org/mail-archive/web/suit/current/index.html
Authors' Addresses
Brendan Moran
Arm Limited
EMail: Brendan.Moran@arm.com
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Hannes Tschofenig
Arm Limited
EMail: hannes.tschofenig@arm.com
Henk Birkholz
Fraunhofer SIT
EMail: henk.birkholz@sit.fraunhofer.de
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