CBOR : : Core - CBOR Platform Profile
draft-rundgren-cbor-core-10
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| Document | Type | Active Internet-Draft (individual) | |
|---|---|---|---|
| Author | Anders Rundgren | ||
| Last updated | 2025-04-26 | ||
| Replaces | draft-rundgren-cbor-base | ||
| RFC stream | (None) | ||
| Intended RFC status | (None) | ||
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draft-rundgren-cbor-core-10
Internet Engineering Task Force A. Rundgren, Ed.
Internet-Draft Independent
Intended status: Informational 26 April 2025
Expires: 28 October 2025
CBOR : : Core - CBOR Platform Profile
draft-rundgren-cbor-core-10
Abstract
This document defines CBOR::Core, a platform profile for CBOR (RFC
8949) intended to serve as a viable replacement for JSON in
computationally advanced systems like Internet browsers, mobile
phones, and Web servers. To foster interoperability, deterministic
encoding is mandated. Furthermore, the document outlines how
deterministic encoding combined with enhanced CBOR tools, enable
cryptographic methods like signing and hashing, to optionally use
"raw" (non-wrapped) CBOR data as input. This document mainly targets
CBOR tool developers.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 28 October 2025.
Copyright Notice
Copyright (c) 2025 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
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extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Design Goals . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Requirements Language . . . . . . . . . . . . . . . . . . 3
1.3. Common Definitions . . . . . . . . . . . . . . . . . . . 3
2. Detailed Description . . . . . . . . . . . . . . . . . . . . 4
2.1. Supported CBOR Objects . . . . . . . . . . . . . . . . . 4
2.2. Deterministic Encoding Scheme . . . . . . . . . . . . . . 5
2.3. Implementation Considerations . . . . . . . . . . . . . . 6
2.3.1. API Requirements . . . . . . . . . . . . . . . . . . 6
2.3.2. Protocol Primitives . . . . . . . . . . . . . . . . . 8
2.3.3. Media Type . . . . . . . . . . . . . . . . . . . . . 10
2.3.4. Diagnostic Notation . . . . . . . . . . . . . . . . . 10
2.3.5. CBOR Sequences . . . . . . . . . . . . . . . . . . . 14
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
4. Security Considerations . . . . . . . . . . . . . . . . . . . 14
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 14
5.1. Normative References . . . . . . . . . . . . . . . . . . 14
5.2. Informative References . . . . . . . . . . . . . . . . . 15
Appendix A. Deterministic Encoding Samples . . . . . . . . . . . 17
A.1. Integers . . . . . . . . . . . . . . . . . . . . . . . . 17
A.2. Floating-Point Numbers . . . . . . . . . . . . . . . . . 19
A.3. Miscellaneous Items . . . . . . . . . . . . . . . . . . . 23
A.4. Invalid Encodings . . . . . . . . . . . . . . . . . . . . 23
Appendix B. Embedded Signatures . . . . . . . . . . . . . . . . 25
B.1. Sample Signature . . . . . . . . . . . . . . . . . . . . 25
B.1.1. Unsigned Data . . . . . . . . . . . . . . . . . . . . 26
B.1.2. Signature Process . . . . . . . . . . . . . . . . . . 26
B.1.3. Validation Process . . . . . . . . . . . . . . . . . 27
B.1.4. Example Parameters . . . . . . . . . . . . . . . . . 28
B.2. Code Example . . . . . . . . . . . . . . . . . . . . . . 28
Appendix C. Supporting Existing Systems . . . . . . . . . . . . 30
Appendix D. Compatible Online Tools . . . . . . . . . . . . . . 30
Appendix E. Compatible Implementations . . . . . . . . . . . . . 30
Document History . . . . . . . . . . . . . . . . . . . . . . . . 31
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 33
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 33
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1. Introduction
The CBOR::Core specification is based on CBOR [RFC8949]. While there
are different ways you can encode certain CBOR objects, this is non-
trivial to support in general purpose platform-based tools, not to
mention the limited utility of such measures. To cope with this,
CBOR::Core defines a specific (non-variant) encoding scheme, aka
"Deterministic Encoding". The selected encoding scheme is believed
to be _compatible_ with most existing systems using CBOR. See also
Appendix C.
CBOR::Core is intended to be agnostic with respect to programming
languages and platforms.
By combining the compact binary representation and the rich set of
data types offered by CBOR, with a deterministic encoding scheme,
CBOR::Core could for _new designs_, serve as a viable alternative to
JSON [RFC8259]. Although the mandated encoding scheme is deployable
in [CONSTRAINED] environments, the primary target is rather general-
purpose computing platforms like mobile phones and Web servers.
However, for unleashing the full power of deterministic encoding, the
ability to perform cryptographic operations on "raw" (non-wrapped)
CBOR data, compliant CBOR::Core tools need additional functionality.
See also Appendix B.
1.1. Design Goals
The primary goal with this specification, is providing a foundation
for CBOR tools that enable application developers to use CBOR without
requiring insights in low-level details like encoding. In most
cases, it should be sufficient to consult a list of supported data
types. See also Section 2.3.2.
Section 2 contains the actual specification.
1.2. Requirements Language
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.
1.3. Common Definitions
* This document uses the conventions defined in CDDL [RFC8610] for
expressing the type of CBOR [RFC8949] data items.
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* Examples showing CBOR data, are expressed in "diagnostic notation"
(Section 2.3.4).
* The term "CBOR object" is equivalent to "CBOR data item" used in
[RFC8949].
2. Detailed Description
This section describes the three pillars that CBOR::Core relies on.
2.1. Supported CBOR Objects
The following table shows the set of CBOR objects that compliant
CBOR::Core implementations MUST support:
+==============+================================+
| CBOR | Comment |
+==============+================================+
| int | Integer |
+--------------+--------------------------------+
| bigint | Big integer |
+--------------+--------------------------------+
| float | 16-, 32-, and 64-bit [IEEE754] |
| | floating-point numbers |
+--------------+--------------------------------+
| tstr | Text string encoded as UTF-8 |
| | [RFC3629] |
+--------------+--------------------------------+
| bstr | Byte string |
+--------------+--------------------------------+
| bool | Boolean true and false |
+--------------+--------------------------------+
| null | Represents a null object |
+--------------+--------------------------------+
| [] | Array |
+--------------+--------------------------------+
| {} | Map |
+--------------+--------------------------------+
| #6.nnn(type) | Tagged objects |
+--------------+--------------------------------+
| #7.nnn | Simple values |
+--------------+--------------------------------+
Table 1: Supported CBOR Objects
Although extensions are imaginable, extensions will most likely cause
_interoperability issues_ and are thus NOT RECOMMENDED.
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However, nothing prevents developers from at the application (API)
level, through CBOR tags and similar mapping concepts, support
additional, "virtual" data types, analogous to how you map an
application's data model to the set of data types available, be it a
data interchange format, a database, or a programming language.
OpenAPI [OPENAPI] is an example of an API that defines data types
through mapping.
_Application-specific_ implementations may (of course) only have to
support the CBOR::Core objects required by the targeted
application(s).
2.2. Deterministic Encoding Scheme
In CBOR::Core deterministic encoding is _mandatory_. The encoding
scheme adheres to Section 4.2 of [RFC8949], but adds a few
constraints (denoted by RFC+), where the RFC offers choices. The
following list contains a summary of the CBOR::Core deterministic
encoding rules:
* RFC+: Floating-point and integer objects MUST be treated as
_distinct types_ regardless of their numeric value. This is
compliant with "Rule 2" in Section 4.2.2 of [RFC8949].
* RFC: Integers, represented by the int and bigint types, MUST use
the int type if the value is between -2^64 and 2^64-1, otherwise
the bigint type MUST be used. Appendix A.1 features a list of
integer sample values and their expected encoding.
* RFC: Floating-point numbers MUST always use the shortest [IEEE754]
variant that preserves the precision of the original value.
Appendix A.2 features a list of floating-point sample values and
their expected encoding.
* RFC+: NaN values with payloads (like f97e01), or having the most
significant bit set ("signaling"), MUST be _rejected_. See also
Appendix A.2.
* RFC: Map keys MUST be sorted in the bytewise lexicographic order
of their deterministic encoding. Duplicate keys MUST be
_rejected_. Somewhat surprisingly the following represents a
properly sorted map:
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{
"a": ... ,
"b": ... ,
"aa": ...
}
* RFC+: Since CBOR encodings according to this specification
maintain uniqueness, there are no specific restrictions or tests
needed in order to determine map key equivalence. As an (extreme)
example, the floating-point numbers 0.0 and -0.0, and the integer
number 0 could represent the distinct keys f90000, f98000, and 00
respectively.
* RFC: Indefinite length objects MUST be _rejected_.
2.3. Implementation Considerations
In CBOR::Core there are three distinguishable levels:
Encoding level:
"Wire format" as described in Section 2.2.
Encoder/decoder level:
This section.
Application level:
Constraints on data imposed by _applications_, like limiting ISO
DateTime objects to UTC notation, or requiring integers
representing enumerations to be in a specific range, is _out-of-
scope_ for CBOR::Core.
2.3.1. API Requirements
An important feature that deterministic encoding brings to the table
is that wrapping CBOR data to be signed in bstr objects, like
specified by COSE in Section 2 of [RFC9052], no longer is a
prerequisite. That is, cryptographic operations can _optionally_ be
performed on "raw" CBOR data. Turn to Appendix B for an example of
an application depending on such features.
However, to make this a reality, the following functionality MUST be
provided by CBOR tools compliant with this specification:
* Decoded CBOR primitives MUST remain _immutable_, regardless if
they are stand-alone or being a part of a tagged object like
bigfloat (see Section 3.4.4 of [RFC8949]).
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* It MUST be possible to find out the type of a decoded CBOR object,
_before_ it is accessed.
* It MUST be possible to _add_, _delete_, and _update_ the contents
of CBOR map and array objects, of decoded CBOR data.
* It MUST be possible to _reserialize_ decoded CBOR data, be it
updated or not.
* Irrespective of if CBOR data is decoded, updated, or created
programmatically, deterministic encoding MUST be maintained.
* Invalid or unsupported CBOR constructs, as well as CBOR data not
adhering to the deterministic encoding scheme MUST be _rejected_.
See also Appendix C and Appendix A.4.
As a consequence of these rules, CBOR data and application /
platform-level data, MUST be _separated_ for cases where
_reserialization_ could present a problem, like in this Chrome
browser console example:
let date = new Date('2025-03-02T13:08:55.0201+03:00');
console.log(date.toISOString());
> 2025-03-02T10:08:55.020Z
How this separation actually is accomplished is out of scope for this
specification. However, _encapsulation_ of CBOR data in _high-
level_, and _self-rendering wrapper objects_, represents an
established method, featured in similar tools for ASN.1. If applied
to the date example above, you would get something like following,
here using [CBOR.JS]:
// "2025-03-02T13:08:55.0201+03:00"
let cbor = CBOR.fromHex("781e323032352d30332d30325431333a30383a35352e303230312b30333a3030");
let cborObject = CBOR.decode(cbor)
// JavaScript Date only supports milliseconds and converts time to UTC
console.log(cborObject.getDateTime().toISOString());
> 2025-03-02T10:08:55.020Z
console.log(CBOR.toHex(cborObject.encode())); // Reencode returns identical CBOR data
> 781e323032352d30332d30325431333a30383a35352e303230312b30333a3030
Fully compliant CBOR::Core implementations SHOULD provide _bi-
directional_ (symmetric) representations of all core objects
(Section 2.1), without requiring a schema or similar.
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Appendix B.2 shows an example that _updates_ and _reserializes_
decoded CBOR data.
2.3.2. Protocol Primitives
To facilitate cross-platform _protocol interoperability_,
implementers of CBOR::Core compatible tools SHOULD include _decoder_
API support for the following primitives:
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+===========+===========+==============================+======+
| CBOR | Primitive | Comment | Note |
+===========+===========+==============================+======+
| int | Int8 | 8-bit signed integer | 1 |
+-----------+-----------+------------------------------+------+
| uint | Uint8 | 8-bit unsigned integer | 1 |
+-----------+-----------+------------------------------+------+
| int | Int16 | 16-bit signed integer | 1 |
+-----------+-----------+------------------------------+------+
| uint | Uint16 | 16-bit unsigned integer | 1 |
+-----------+-----------+------------------------------+------+
| int | Int32 | 32-bit signed integer | 1 |
+-----------+-----------+------------------------------+------+
| uint | Uint32 | 32-bit unsigned integer | 1 |
+-----------+-----------+------------------------------+------+
| int | Int64 | 64-bit signed integer | 1 |
+-----------+-----------+------------------------------+------+
| uint | Uint64 | 64-bit unsigned integer | 1 |
+-----------+-----------+------------------------------+------+
| integer | BigInt | Integer of arbitrary size | 2 |
+-----------+-----------+------------------------------+------+
| float16 | Float16 | 16-bit floating-point number | 3 |
+-----------+-----------+------------------------------+------+
| float16 / | Float32 | 32-bit floating-point number | 3 |
| float32 | | | |
+-----------+-----------+------------------------------+------+
| float | Float64 | 64-bit floating-point number | |
+-----------+-----------+------------------------------+------+
| bool | Boolean | Boolean | |
+-----------+-----------+------------------------------+------+
| null | Null | Null | 4 |
+-----------+-----------+------------------------------+------+
| #7.nnn | Simple | Simple values | 5 |
+-----------+-----------+------------------------------+------+
| tstr | String | Text string | |
+-----------+-----------+------------------------------+------+
| bstr | Bytes | Byte string | |
+-----------+-----------+------------------------------+------+
| See note | EpochTime | Time object expressed as a | 6 |
| | | number | |
+-----------+-----------+------------------------------+------+
| See note | DateTime | Time object expressed as a | 6 |
| | | text string | |
+-----------+-----------+------------------------------+------+
Table 2: Protocol Primitives
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1. Range testing MUST be performed using the traditional ranges for
_unsigned_ respectively _two-complement_ numbers. That is, a
hypothetical getUint8() MUST reject numbers outside of 0 to 255,
whereas a hypothetical getInt8(), MUST reject numbers outside of
-128 to 127.
2. Note that a hypothetical getBigInt() MUST also accept CBOR int
objects since int is used for integers that fit in CBOR major
type 0 and 1 objects. See also Appendix A.1 and Appendix C.
3. Some platforms do not natively support float32 and/or float16.
In this case a hypothetical getFloat16() would need to use a
bigger floating-point type for the return value.
Note that a hypothetical getFloat16() MUST reject encountered
Float32 and Float64 objects. See also Appendix C.
4. Since a CBOR null typically represents the absence of a value, a
decoder MUST provide a test-function, like isNull().
5. Simple values include the ranges 0-23 and 32-255. Note that bool
and null actually are simple values.
6. Since CBOR lacks a native-level time object, Section 3.4 of
[RFC8949] introduces two variants of time objects using the CBOR
tags 0 and 1. The time objects SHOULD also be supported without
the tag construct.
If a call does not match the underlying CBOR type, the call MUST be
rejected,
Due to considerable variations between platforms, corresponding
_encoder_ API support does not appear to be meaningful to specify in
detail: Java doesn't have built-in support for unsigned integers,
whereas JavaScript requires the use of the JavaScript BigInt type for
dealing with 64-bit integers.
2.3.3. Media Type
Protocols building on CBOR::Core, are RECOMMENDED using the media
type: application/cbor.
2.3.4. Diagnostic Notation
Compliant CBOR::Core implementations SHOULD include support for _bi-
directional_ diagnostic notation, to facilitate:
* Generation of developer-friendly debugging and logging data
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* Easy creation of test and configuration data
Note that decoders for diagnostic notation, MUST always produce
deterministically encoded CBOR data, compliant with this
specification. This includes _automatic_ sorting of map keys as
well.
The supported notation is compliant with a subset of Section 8 of
[RFC8949] (b32' and encoding indicators were left out), but adds a
few items to make diagnostic notation slightly more adapted for
parsing, like single-line comments:
+=======+================================+==================+=======+
| CBOR | Syntax | Comment | Notes |
+=======+================================+==================+=======+
| | / _comment text_ / |Multi-line | 6 |
| | |comment. Multi- | |
| | |line comments are | |
| | |treated as | |
| | |whitespace and | |
| | |may thus also be | |
| | |used _between_ | |
| | |CBOR objects. | |
+-------+--------------------------------+------------------+-------+
| | # _comment text_ |Single-line | 6 |
| | |comment. Single- | |
| | |line comments are | |
| | |terminated by a | |
| | |newline character | |
| | |('\n') or EOF. | |
| | |Single-line | |
| | |comments may also | |
| | |terminate lines | |
| | |holding regular | |
| | |CBOR items. | |
+-------+--------------------------------+------------------+-------+
|integer| _{sign} { _0b|0o|0x_} n_ |Arbitrary sized | 1, 2 |
| | |integers without | |
| | |fractional | |
| | |components or | |
| | |exponents. See | |
| | |also CBOR integer | |
| | |encoding. For | |
| | |_input_ data in | |
| | |diagnostic | |
| | |notation, binary, | |
| | |octal, and | |
| | |hexadecimal | |
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| | |notation is also | |
| | |supported by | |
| | |prepending | |
| | |numbers with 0b, | |
| | |0o, and 0x | |
| | |respectively. | |
| | |The latter also | |
| | |permit arbitrary | |
| | |insertions of '_' | |
| | |characters | |
| | |between digits to | |
| | |enable grouping | |
| | |of data like | |
| | |0b100_000000001. | |
+-------+--------------------------------+------------------+-------+
| float | _{sign} n_._n { _e±_n }_ |Floating-point | 1, 2 |
| | |values MUST | |
| | |include a decimal | |
| | |point and at | |
| | |least one | |
| | |fractional digit, | |
| | |whereas exponents | |
| | |are _optional_. | |
+-------+--------------------------------+------------------+-------+
| float | NaN |Not a number. | |
+-------+--------------------------------+------------------+-------+
| float | _{sign} _Infinity |Infinity. | 2 |
+-------+--------------------------------+------------------+-------+
| bstr | h'_hex-data_' |Byte data | 3 |
| | |provided in | |
| | |hexadecimal | |
| | |notation. Each | |
| | |byte MUST be | |
| | |represented by | |
| | |two hexadecimal | |
| | |digits. | |
+-------+--------------------------------+------------------+-------+
| bstr | b64'_base64-data_' |Byte data | 3, 6 |
| | |provided in | |
| | |base64 or | |
| | |base64URL | |
| | |notation. | |
| | |Padding with '=' | |
| | |characters is | |
| | |_optional_. | |
+-------+--------------------------------+------------------+-------+
| bstr | '_text_' |Byte data |4, 5, 6|
| | |provided as UTF-8 | |
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| | |encoded text. | |
+-------+--------------------------------+------------------+-------+
| bstr | << _object..._ >> |Construct holding | 6 |
| | |zero or more | |
| | |comma-separated | |
| | |CBOR objects that | |
| | |are subsequently | |
| | |wrapped in a byte | |
| | |string. | |
+-------+--------------------------------+------------------+-------+
| tstr | "_text_" |UTF-8 encoded | 4, 5 |
| | |text string. | |
+-------+--------------------------------+------------------+-------+
| bool | true | false |Boolean value. | |
+-------+--------------------------------+------------------+-------+
| null | null |Null value. | |
+-------+--------------------------------+------------------+-------+
| [] | [ _object..._ ] |Array with zero | |
| | |or more comma- | |
| | |separated CBOR | |
| | |objects. | |
+-------+--------------------------------+------------------+-------+
| {} | { _key_:_value..._ } |Map with zero or | |
| | |more comma- | |
| | |separated key/ | |
| | |value pairs. Key | |
| | |and value pairs | |
| | |are expressed as | |
| | |CBOR objects, | |
| | |separated by a | |
| | |':' character. | |
+-------+--------------------------------+------------------+-------+
| #6.nnn| _n_ ( _object_ ) |Tag holding a | 1 |
| | |CBOR object. | |
+-------+--------------------------------+------------------+-------+
| #7.nnn| simple(_n_) |Simple value. | 1 |
+-------+--------------------------------+------------------+-------+
| | , |Separator | 6 |
| | |character for | |
| | |CBOR sequences. | |
+-------+--------------------------------+------------------+-------+
Table 3: Diagnostic Notation
1. The letter _n_ in the Syntax column denotes one or more digits.
2. The optional _{sign}_ MUST be a single hyphen ('-') character.
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3. _Input only_: between the quotes, the whitespace characters (' ',
'\t', '\r', '\n') are _ignored_.
4. _Input only_: the control characters '\t' and '\n' inside of
string quotes _become a part of the text_. For normalizing line
terminators, a single '\r' or the combination '\r\n' MUST
(internally) be rewritten as '\n'. To _avoid_ getting newline
characters ('\n') included in multi-line text strings, a _line
continuation marker_ consisting of a backslash ('\') immediately
preceding the newline may be used.
5. Text strings may also include JavaScript compatible escape
sequences ('\'', '\"', '\\', '\b', '\f', '\n', '\r', '\t',
'\u_hhhh_').
6. _Input only_.
The [PLAYGROUND] is an excellent way of getting acquainted with CBOR
and diagnostic notation.
2.3.5. CBOR Sequences
Decoders compliant with this specification MUST support CBOR
sequences [RFC8742].
For decoders of "true" (binary) CBOR, there are additional
requirements:
* It MUST be possible to decode one CBOR object at a time.
* The decoder MUST NOT do any assumptions about the nature of unread
code (it might not even be CBOR).
3. IANA Considerations
This memo includes no request to IANA.
4. Security Considerations
CBOR::Core does not introduce security issues beyond what is already
applicable to [RFC8949].
Poorly written tools and applications may certainly introduce
security issues, but this is out of scope for this specification.
5. References
5.1. 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>.
[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>.
[RFC8949] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", STD 94, RFC 8949,
DOI 10.17487/RFC8949, December 2020,
<https://www.rfc-editor.org/info/rfc8949>.
[RFC8610] Birkholz, H., Vigano, C., and C. Bormann, "Concise Data
Definition Language (CDDL): A Notational Convention to
Express Concise Binary Object Representation (CBOR) and
JSON Data Structures", RFC 8610, DOI 10.17487/RFC8610,
June 2019, <https://www.rfc-editor.org/info/rfc8610>.
[RFC3629] Yergeau, F., "UTF-8, a transformation format of ISO
10646", STD 63, RFC 3629, DOI 10.17487/RFC3629, November
2003, <https://www.rfc-editor.org/info/rfc3629>.
[RFC8742] Bormann, C., "Concise Binary Object Representation (CBOR)
Sequences", RFC 8742, DOI 10.17487/RFC8742, February 2020,
<https://www.rfc-editor.org/info/rfc8742>.
[IEEE754] IEEE, "IEEE Standard for Floating-Point Arithmetic", IEEE
Std 754-2019, DOI 10.1109/IEEESTD.2019.8766229,
<https://ieeexplore.ieee.org/document/8766229>.
5.2. Informative References
[RFC9052] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Structures and Process", STD 96, RFC 9052,
DOI 10.17487/RFC9052, August 2022,
<https://www.rfc-editor.org/info/rfc9052>.
[RFC9053] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Initial Algorithms", RFC 9053, DOI 10.17487/RFC9053,
August 2022, <https://www.rfc-editor.org/info/rfc9053>.
[RFC8785] Rundgren, A., Jordan, B., and S. Erdtman, "JSON
Canonicalization Scheme (JCS)", RFC 8785,
DOI 10.17487/RFC8785, June 2020,
<https://www.rfc-editor.org/info/rfc8785>.
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[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
[CSF] Rundgren, A., "CBOR Signature Format (CSF)",
<https://cyberphone.github.io/javaapi/org/webpki/cbor/doc-
files/signatures.html>.
[CEF] Rundgren, A., "CBOR Encryption Format (CEF)",
<https://cyberphone.github.io/javaapi/org/webpki/cbor/doc-
files/encryption.html>.
[COTX] Rundgren, A., "CBOR Object Type Extension (COTX)",
<https://www.ietf.org/archive/id/draft-rundgren-cotx-
04.html>.
[CONSTRAINED]
"D-CBOR for Constrained Devices",
<https://github.com/cyberphone/D-CBOR/blob/main/d-cbor-4-
constrained-devices.md>.
[NODE.JS] "Node.js - JavaScript server", <https://nodejs.org/>.
[CBOR.JS] "CBOR.js - CBOR for JavaScript",
<https://github.com/cyberphone/CBOR.js>.
[CSF-LAB] "Online CBOR and CSF test tool",
<https://test.webpki.org/csf-lab>.
[PLAYGROUND]
"Online CBOR testing tool",
<https://cyberphone.github.io/CBOR.js/doc/
playground.html>.
[OPENKEYSTORE]
"Java library supporting JSON, CBOR, and Crypto",
<https://github.com/cyberphone/openkeystore>.
[ANDROID-CBOR]
"Android/Java library supporting CBOR and Crypto",
<https://github.com/cyberphone/android-cbor>.
[OPENAPI] "The OpenAPI Initiative", <https://openapis.org/>.
[CREDENTIALS]
Sporny (et al), M., "Verifiable Credential Data Integrity
1.0", 2025, <https://www.w3.org/TR/vc-data-integrity/>.
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[CBOR.ME] Bormann, C., "Online CBOR testing tool",
<https://cbor.me/>.
[ECMASCRIPT]
Ecma International, "ECMAScript® 2024 Language
Specification", Standard ECMA-262, 15th Edition, June
2024, <https://www.ecma-
international.org/publications/standards/Ecma-262.htm>.
[WALLET] Rundgren, A., "Defensive publication: Partial Encryption,
Full Signature", <https://cyberphone.github.io/doc/
defensive-publications/partial-encryption-full-
signature.pdf>.
Appendix A. Deterministic Encoding Samples
A.1. Integers
This _normative_ section holds a selection of CBOR integer values,
with an emphasize on edge cases.
+=======================+========================+================+
| Diagnostic Notation | CBOR Encoding | Comment |
+=======================+========================+================+
| 0 | 00 | Smallest |
| | | positive |
| | | implicit int |
+-----------------------+------------------------+----------------+
| -1 | 20 | Smallest |
| | | negative |
| | | implicit int |
+-----------------------+------------------------+----------------+
| 23 | 17 | Largest |
| | | positive |
| | | implicit int |
+-----------------------+------------------------+----------------+
| -24 | 37 | Largest |
| | | negative |
| | | implicit int |
+-----------------------+------------------------+----------------+
| 24 | 1818 | Smallest |
| | | positive one- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -25 | 3818 | Smallest |
| | | negative one- |
| | | byte int |
+-----------------------+------------------------+----------------+
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| 255 | 18ff | Largest |
| | | positive one- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -256 | 38ff | Largest |
| | | negative one- |
| | | byte int |
+-----------------------+------------------------+----------------+
| 256 | 190100 | Smallest |
| | | positive two- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -257 | 390100 | Smallest |
| | | negative two- |
| | | byte int |
+-----------------------+------------------------+----------------+
| 65535 | 19ffff | Largest |
| | | positive two- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -65536 | 39ffff | Largest |
| | | negative two- |
| | | byte int |
+-----------------------+------------------------+----------------+
| 65536 | 1a00010000 | Smallest |
| | | positive four- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -65537 | 3a00010000 | Smallest |
| | | negative four- |
| | | byte int |
+-----------------------+------------------------+----------------+
| 4294967295 | 1affffffff | Largest |
| | | positive four- |
| | | byte int |
+-----------------------+------------------------+----------------+
| -4294967296 | 3affffffff | Largest |
| | | negative four- |
| | | byte int |
+-----------------------+------------------------+----------------+
| 4294967296 | 1b0000000100000000 | Smallest |
| | | positive |
| | | eight-byte int |
+-----------------------+------------------------+----------------+
| -4294967297 | 3b0000000100000000 | Smallest |
| | | negative |
| | | eight-byte int |
+-----------------------+------------------------+----------------+
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| 18446744073709551615 | 1bffffffffffffffff | Largest |
| | | positive |
| | | eight-byte int |
+-----------------------+------------------------+----------------+
| -18446744073709551616 | 3bffffffffffffffff | Largest |
| | | negative |
| | | eight-byte int |
+-----------------------+------------------------+----------------+
| 18446744073709551616 | c249010000000000000000 | Smallest |
| | | positive |
| | | bigint |
+-----------------------+------------------------+----------------+
| -18446744073709551617 | c349010000000000000000 | Smallest |
| | | negative |
| | | bigint |
+-----------------------+------------------------+----------------+
Table 4: Integers
A.2. Floating-Point Numbers
This _normative_ section holds a selection of [IEEE754] 16, 32, and
64-bit values, with an emphasize on edge cases.
The textual representation of the values is based on the
serialization method for the Number data type, defined by
[ECMASCRIPT] with one change: to comply with diagnostic notation
(Section 2.3.4), all values are expressed as floating-point numbers.
The rationale for using [ECMASCRIPT] serialization is because it is
supposed to generate the shortest and most correct representation of
[IEEE754] numbers.
+===========================+====================+==================+
| Diagnostic Notation | CBOR Encoding | Comment |
+===========================+====================+==================+
| 0.0 | f90000 | Zero |
+---------------------------+--------------------+------------------+
| -0.0 | f98000 | Negative |
| | | zero |
+---------------------------+--------------------+------------------+
| Infinity | f97c00 | Infinity |
+---------------------------+--------------------+------------------+
| -Infinity | f9fc00 | Negative |
| | | infinity |
+---------------------------+--------------------+------------------+
| NaN | f97e00 | Not a number |
+---------------------------+--------------------+------------------+
| 5.960464477539063e-8 | f90001 | Smallest |
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| | | positive |
| | | subnormal |
| | | float16 |
+---------------------------+--------------------+------------------+
| 0.00006097555160522461 | f903ff | Largest |
| | | positive |
| | | subnormal |
| | | float16 |
+---------------------------+--------------------+------------------+
| 0.00006103515625 | f90400 | Smallest |
| | | positive |
| | | float16 |
+---------------------------+--------------------+------------------+
| 65504.0 | f97bff | Largest |
| | | positive |
| | | float16 |
+---------------------------+--------------------+------------------+
| 1.401298464324817e-45 | fa00000001 | Smallest |
| | | positive |
| | | subnormal |
| | | float32 |
+---------------------------+--------------------+------------------+
| 1.1754942106924411e-38 | fa007fffff | Largest |
| | | positive |
| | | subnormal |
| | | float32 |
+---------------------------+--------------------+------------------+
| 1.1754943508222875e-38 | fa00800000 | Smallest |
| | | positive |
| | | float32 |
+---------------------------+--------------------+------------------+
| 3.4028234663852886e+38 | fa7f7fffff | Largest |
| | | positive |
| | | float32 |
+---------------------------+--------------------+------------------+
| 5.0e-324 | fb0000000000000001 | Smallest |
| | | positive |
| | | subnormal |
| | | float64 |
+---------------------------+--------------------+------------------+
| 2.225073858507201e-308 | fb000fffffffffffff | Largest |
| | | positive |
| | | subnormal |
| | | float64 |
+---------------------------+--------------------+------------------+
| 2.2250738585072014e-308 | fb0010000000000000 | Smallest |
| | | positive |
| | | float64 |
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+---------------------------+--------------------+------------------+
| 1.7976931348623157e+308 | fb7fefffffffffffff | Largest |
| | | positive |
| | | float64 |
+---------------------------+--------------------+------------------+
| -0.0000033333333333333333 | fbbecbf647612f3696 | Randomly |
| | | selected |
| | | number |
+---------------------------+--------------------+------------------+
| 10.559998512268066 | fa4128f5c1 | -"- |
+---------------------------+--------------------+------------------+
| 10.559998512268068 | fb40251eb820000001 | Next in |
| | | succession |
+---------------------------+--------------------+------------------+
| 295147905179352830000.0 | fa61800000 | 2^68 |
| | | (diagnostic |
| | | notation |
| | | truncates |
| | | precision) |
+---------------------------+--------------------+------------------+
| 2.0 | f94000 | Number |
| | | without a |
| | | fractional |
| | | part |
+---------------------------+--------------------+------------------+
| -5.960464477539063e-8 | f98001 | Smallest |
| | | negative |
| | | subnormal |
| | | float16 |
+---------------------------+--------------------+------------------+
| -5.960464477539062e-8 | fbbe6fffffffffffff | Adjacent |
| | | smallest |
| | | negative |
| | | subnormal |
| | | float16 |
+---------------------------+--------------------+------------------+
| -5.960464477539064e-8 | fbbe70000000000001 | -"- |
+---------------------------+--------------------+------------------+
| -5.960465188081798e-8 | fab3800001 | -"- |
+---------------------------+--------------------+------------------+
| 0.0000609755516052246 | fb3f0ff7ffffffffff | Adjacent |
| | | largest |
| | | subnormal |
| | | float16 |
+---------------------------+--------------------+------------------+
| 0.000060975551605224616 | fb3f0ff80000000001 | -"- |
+---------------------------+--------------------+------------------+
| 0.000060975555243203416 | fa387fc001 | -"- |
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+---------------------------+--------------------+------------------+
| 0.00006103515624999999 | fb3f0fffffffffffff | Adjacent |
| | | smallest |
| | | float16 |
+---------------------------+--------------------+------------------+
| 0.00006103515625000001 | fb3f10000000000001 | -"- |
+---------------------------+--------------------+------------------+
| 0.00006103516352595761 | fa38800001 | -"- |
+---------------------------+--------------------+------------------+
| 65503.99999999999 | fb40effbffffffffff | Adjacent |
| | | largest |
| | | float16 |
+---------------------------+--------------------+------------------+
| 65504.00000000001 | fb40effc0000000001 | -"- |
+---------------------------+--------------------+------------------+
| 65504.00390625 | fa477fe001 | -"- |
+---------------------------+--------------------+------------------+
| 1.4012984643248169e-45 | fb369fffffffffffff | Adjacent |
| | | smallest |
| | | subnormal |
| | | float32 |
+---------------------------+--------------------+------------------+
| 1.4012984643248174e-45 | fb36a0000000000001 | -"- |
+---------------------------+--------------------+------------------+
| 1.175494210692441e-38 | fb380fffffbfffffff | Adjacent |
| | | largest |
| | | subnormal |
| | | float32 |
+---------------------------+--------------------+------------------+
| 1.1754942106924412e-38 | fb380fffffc0000001 | -"- |
+---------------------------+--------------------+------------------+
| 1.1754943508222874e-38 | fb380fffffffffffff | Adjacent |
| | | smallest |
| | | float32 |
+---------------------------+--------------------+------------------+
| 1.1754943508222878e-38 | fb3810000000000001 | -"- |
+---------------------------+--------------------+------------------+
| 3.4028234663852882e+38 | fb47efffffdfffffff | Adjacent |
| | | largest |
| | | float32 |
+---------------------------+--------------------+------------------+
| 3.402823466385289e+38 | fb47efffffe0000001 | -"- |
+---------------------------+--------------------+------------------+
Table 5: Floating-Point Numbers
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A.3. Miscellaneous Items
This _normative_ section holds a selection of miscellaneous CBOR
objects and their encoding.
+=======================================+==========================+============+
| Diagnostic Notation | CBOR Encoding | Comment |
+=======================================+==========================+============+
|true |f5 |Boolean true|
+---------------------------------------+--------------------------+------------+
|null |f6 |Null |
+---------------------------------------+--------------------------+------------+
|simple(59) |f83b |Simple value|
+---------------------------------------+--------------------------+------------+
|0("2025-03-30T12:24:16Z") |c074323032352d30332d33 |ISO date/ |
| |305431323a32343a31365a |time |
+---------------------------------------+--------------------------+------------+
|[1, [2, 3], [4, 5]] |8301820203820405 |Array |
| | |combinations|
+---------------------------------------+--------------------------+------------+
|{ |a361610161620262616103 |Map object |
|"a": 0, | | |
|"b": 1, | | |
|"aa": 2 | | |
|} | | |
+---------------------------------------+--------------------------+------------+
|h'48656c6c6f2043424f5221' |4b48656c6c6f2043424f5221 |Binary |
| | |string |
+---------------------------------------+--------------------------+------------+
|"🚀 science" |6cf09f9a8020736369656e6365|Text string |
| | |with emoji |
+---------------------------------------+--------------------------+------------+
Table 6: Miscellaneous Items
A.4. Invalid Encodings
The following table holds a selection of CBOR-encoded objects, not
permitted by CBOR::Core.
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+========================+=====================+================+=====+
| CBOR Encoding | Diagnostic Notation | Comment |Notes|
+========================+=====================+================+=====+
|a2616201616100 |{ |Improper map key| 1, 2|
| |"b": 1, |ordering | |
| |"a": 0 | | |
| |} | | |
+------------------------+---------------------+----------------+-----+
|98020405 |[4, 5] |Improper array | 1, 2|
| | |length indicator| |
+------------------------+---------------------+----------------+-----+
|1900ff |255 |Number with | 1, 2|
| | |leading zero | |
| | |bytes | |
+------------------------+---------------------+----------------+-----+
|c34a00010000000000000000|-18446744073709551617|Number with | 1, 2|
| | |leading zero | |
| | |bytes | |
+------------------------+---------------------+----------------+-----+
|Fa41280000 |10.5 |Not in shortest | 1, 2|
| | |encoding | |
+------------------------+---------------------+----------------+-----+
|fa7fc00000 |NaN |Not in shortest | 1, 2|
| | |encoding | |
+------------------------+---------------------+----------------+-----+
|c243010000 |65536 |Incorrect value | 1, 2|
| | |for bigint | |
+------------------------+---------------------+----------------+-----+
|f97e01 |NaN |NaN with payload| 1, 2|
+------------------------+---------------------+----------------+-----+
|5f4101420203ff |(_ h'01', h'0203') |Indefinite | 2 |
| | |length object | |
+------------------------+---------------------+----------------+-----+
|fc | |Reserved | |
+------------------------+---------------------+----------------+-----+
|f818 | |Invalid simple | |
| | |value | |
+------------------------+---------------------+----------------+-----+
|5b0010000000000000 | |Extremely large | |
| | |bstr length | |
| | |indicator: | |
| | |4503599627370496| |
+------------------------+---------------------+----------------+-----+
Table 7: Invalid Encodings
1. See also Appendix C.
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2. _Non-deterministically_ encoded CBOR supported by [RFC8949].
Appendix B. Embedded Signatures
This is a _non-normative_ appendix showing how CBOR::Core can be used
for supporting embedded signatures.
The primary advantages with _embedded_ signatures compared to
_enveloping_ signatures (like used by COSE [RFC9052]), include:
* Keeping the _structure_ of the original (unsigned) data intact, by
simply making signatures an additional attribute.
* Enabling top-level, _object identifiers_ to become a part of the
signed data as well:
123456789({ # CBOR tag (objectId)
1: "This is not rocket science!", # Object instance data
2: [38.8882, -77.01988], # ""
simple(99): «signature covering the entire object»
})
See also [COTX].
* Permitting signing CBOR data and associated security attributes
(aka "headers"), _in one go_, without having to wrap data in CBOR
"bstr" objects. Non-wrapped data also makes debugging and
documentation easier.
Embedded signatures are for example featured in Verified Credentials
[CREDENTIALS]. A drawback with designs based on JSON [RFC8259] is
that they rely on _canonicalization schemes_ like JCS [RFC8785], that
require specialized encoders and decoders, whereas CBOR::Core works
"straight out of the box".
B.1. Sample Signature
Although this specification is not "married" to any particular
signature schema, the following example uses the CBOR Signature
Format [CSF]. For the sake of simplicity, the example uses an HMAC
(see Appendix B.1.4) as signature algorithm.
For a more sophisticated use of CBOR::Core, combining signatures and
encryption, see [WALLET].
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B.1.1. Unsigned Data
Imagine you have a CBOR map object like the following that you want
to sign:
{
1: "data",
2: "more data"
}
B.1.2. Signature Process
This section describes the steps required for adding an embedded
signature to the CBOR map object in Appendix B.1.1. To avoid
confusing CBOR map keys with cryptographic keys, the former are
referred to as "labels".
1. Add an empty CSF container (a CBOR map) to the unsigned CBOR map
using the CSF container label simple(99).
2. Add the designated signature algorithm to the CSF container using
the CSF algorithm label (1).
3. _Optional_. Add other signature meta data to the CSF container.
Not used in the example.
4. Generate a signature by invoking a (hypothetical) signature
method with the following arguments:
* the designated signature key.
* the designated signature algorithm.
* the _deterministic encoding_ of the current CBOR object in its
_entirety_. In the example that would be
a301646461746102696d6f7265206461746120a10105, if expressed in
hex code.
5. Add the returned signature value to the CSF container using the
CSF signature label (6).
The result after the final step (using the parameters from
Appendix B.1.4), should match the following CBOR object:
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{
1: "data",
2: "more data",
simple(99): {
1: 5,
6: h'237e674c7be1818ddd7eaacf40ca80415b9ad816880751d2136c45385207420c'
}
}
Note that the signature covers the _entire_ CBOR object except for
the CSF signature value and label (6).
B.1.3. Validation Process
In order to validate the embedded signature created in the
Appendix B.1.2, the following steps are performed:
1. Fetch a _reference_ to the CSF container using the CSF container
label simple(99). Next perform the following operations using
the reference:
1. Retrieve the signature algorithm using the CSF algorithm
label (1).
2. Retrieve the signature value using the CSF algorithm label
(6).
3. Remove the CSF algorithm label (6) and its associated value.
Now we should have exactly the same CBOR object as we had
_before_ step #4 in Appendix B.1.2. That is:
{
1: "data",
2: "more data",
-1: {
1: 5
}
}
2. Validate the signature data by invoking a (hypothetical)
signature validation method with the following arguments:
* the designated signature key (in the example taken from
Appendix B.1.4).
* the signature algorithm retrieved in step #1.
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* the signature value retrieved in step #1.
* the _deterministic encoding_ of the current CBOR object in its
_entirety_.
Note: this is a "bare-bones" validation process, lacking the
ruggedness of a real-world implementation.
B.1.4. Example Parameters
The signature and validation processes depend on the COSE [RFC9053]
algorithm "HMAC 256/256" and an associated 256-bit key, here provided
in hex code:
7fdd851a3b9d2dafc5f0d00030e22b9343900cd42ede4948568a4a2ee655291a
B.2. Code Example
Using a JavaScript implementation [CBOR.JS] of CBOR::Core, together
with Node.js [NODE.JS], basic signature creation and validation
supporting the example in Appendix B.1, could be performed by the
following code:
// hmac.mjs
import CBOR from 'cbor-object';
const crypto = await import('node:crypto');
// Application independent CSF constants
const CSF_CONTAINER_LBL = CBOR.Simple(99);
const CSF_ALG_LBL = CBOR.Int(1);
const CSF_SIG_LBL = CBOR.Int(6);
// COSE => Node.js algorithm translation
const HASH_ALGORITHMS = new Map()
.set(5, "sha256").set(6, "sha384").set(7, "sha512");
function hmac(coseAlg, key, data) {
let alg = HASH_ALGORITHMS.get(coseAlg);
if (alg === undefined) throw "Unknown alg: " + coseAlg;
return crypto.createHmac(alg, key).update(data).digest();
}
const SHARED_KEY = crypto.createSecretKey(
'7fdd851a3b9d2dafc5f0d00030e22b9343900cd42ede4948568a4a2ee655291a', 'hex');
const APP_P1_LBL = CBOR.Int(1); // Application label
const APP_P2_LBL = CBOR.Int(2); // ""
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////////////////////////////////////
// Create an unsigned CBOR object //
////////////////////////////////////
let object = CBOR.Map()
.set(APP_P1_LBL, CBOR.String("data")) // Application data
.set(APP_P2_LBL, CBOR.String("more data")); // ""
////////////////////////////////////////
// Add a signature to the CBOR object //
////////////////////////////////////////
const COSE_ALG = 5; // Selected HMAC algorithm
let csf = CBOR.Map() // Create CSF container and
.set(CSF_ALG_LBL, CBOR.Int(COSE_ALG)); // add COSE algorithm to it
object.set(CSF_CONTAINER_LBL, csf); // Add CSF container to object
let sig = hmac(COSE_ALG, // Generate signature over
SHARED_KEY, // the current object
object.encode()); // encode(): all we got so far
csf.set(CSF_SIG_LBL, CBOR.Bytes(sig)); // Add signature to CSF container
let cborBinary = object.encode(); // Return CBOR as an Uint8Array
console.log(object.toString()); // Show in Diagnostic Notation
/////////////////////////////////////
// Validate the signed CBOR object //
/////////////////////////////////////
object = CBOR.decode(cborBinary); // Decode CBOR object
csf = object.get(CSF_CONTAINER_LBL); // Get CSF container
let alg = csf.get(CSF_ALG_LBL).getInt(); // Get COSE algorithm
let readSig = csf.remove(CSF_SIG_LBL).getBytes(); // Get and REMOVE signature value
let actualSig = hmac(alg, // Calculate signature over
SHARED_KEY, // the current object
object.encode()); // encode(): all but the signature
if (CBOR.compareArrays(readSig, actualSig)) { // HMAC validation
throw "Signature did not validate";
}
// Validated object, access the "payload":
let p1 = object.get(APP_P1_LBL).getString(); // p1 should now contain "data"
Note that this code depends heavily on the API features outlined in
Section 2.3.1.
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Appendix C. Supporting Existing Systems
It is assumed that _most_ systems using CBOR are able to process an
(_application specific_), selection of CBOR data items that are
encoded in compliance with [RFC8949]. Since the deterministic
encoding scheme mandated by CBOR::Core, also is compliant with
[RFC8949] (as well as with [CBOR.ME]), there should be no major
interoperability issues. That is, if the previous assumption
actually is correct 😏
However, in the _other_ direction (CBOR::Core tools processing data
from systems using "legacy" CBOR encoding schemes), the situation is
likely to be considerably more challenging since deterministic
encoding "by design" is _strict_. Due to this potential obstacle,
implementers of CBOR::Core tools, are RECOMMENDED to offer _decoder_
options that permit "relaxing" the rigidness of deterministic
encoding with respect to:
Numbers:
Numbers MUST still be compliant with [RFC8949], including "Rule 2"
in section 4.2.2.
Sorted maps:
Duplicate keys MUST still be rejected.
Note that regardless of the format of decoded CBOR data, a compliant
CBOR::Core implementation MUST maintain deterministic encoding. See
also Appendix A.4.
Appendix D. Compatible Online Tools
For testing and learning about CBOR::Core, there are currently a
number of compatible online tools (subject to availability...).
[PLAYGROUND]:
Browser-based CBOR "playground"
[CSF-LAB]:
Server-based CBOR and [CSF] test system
Appendix E. Compatible Implementations
For using CBOR::Core in applications, there are currently a number of
compatible libraries.
[CBOR.JS]:
JavaScript-based implementation supporting browsers as well as
[NODE.JS]
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[OPENKEYSTORE]:
Java-based implementation that also supports [CSF] and [CEF]
[ANDROID-CBOR]:
Android Java-based implementation that also supports [CSF] and
[CEF]
Document History
* 00. First cut.
* 01. Editorial. Changed order of columns in invalid encoding.
* 02. Editorial. "unwrapped" changed to "non-wrapped".
* 03:
Tweaking the abstract.
Protocol Primitives sub-section added.
Diagnostic Notation sub-section added.
Updated CBOR Tool Requirements
Updated code example to actually use crypto
Updated Acknowledgements.
Updated Security Considerations.
* 04:
Minor addition in CBOR tools
Updated Acknowledgements
* 05:
Regression bug fix
* 06:
Media type added
* 07->00:
Renamed from "Universal CBOR" to "CBOR Base"
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Design Goals added
CBOR Sequences added
* 01:
#7.nnn (simple) added
Language nits
* 02->00:
Renamed from "CBOR Base" to "CBOR Core"
Language nits
Miscellaneous Items added
* 01:
Language nits
<table align="left">
* 02:
Editorial
* 03:
Added Date decode/reencode example
* 04:
Editorial
Added bstr and tstr to Protocol Primitives
* 05:
Enveloped => Embedded (signature)
* 06:
Updated Acknowledgements
* 07:
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Dropped CBOR/c. Now it is just CBOR::Core
Introduced API Level Considerations
Updated Date example, and added Rule 2 to Supporting Existing
Systems
* 08:
Elaborated on "levels"
CBOR/Core => CBOR::Core (showing its close ties to software)
* 09:
Embedded signature sample => simple(99)
* 10:
Editorial
CBOR Profile => CBOR Platform Profile
Acknowledgements
For verifying the correctness of the encoding scheme, the [CBOR.ME]
on-line CBOR tool, by the [RFC8949] author, Carsten Bormann, proved
to be invaluable.
Non-exhaustive list of people who directly (and sometimes indirectly)
contributed to this specification include: Carsten Bormann, Alan
DeKok, Vadim Goncharov, Joe Hildebrand, Laurence Lundblade, Rohan
Mahy, Michael Richardson, Göran Selander, and Orie Steele.
Author's Address
Anders Rundgren (editor)
Independent
Montpellier
France
Email: anders.rundgren.net@gmail.com
URI: https://www.linkedin.com/in/andersrundgren/
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