Initial commit.

.pre-commit-config.yaml

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+repos:
+  - repo: https://github.com/psf/black
+    rev: 20.8b1
+    hooks:
+      - id: black
+        args: ["--target-version=py36"]
+
+  - repo: https://github.com/asottile/blacken-docs
+    rev: v1.10.0
+    hooks:
+      - id: blacken-docs
+        args: ["--target-version=py36"]
+
+  - repo: https://github.com/PyCQA/flake8
+    rev: 3.9.0
+    hooks:
+      - id: flake8
+        language_version: python3.8
+
+  - repo: https://github.com/PyCQA/isort
+    rev: 5.8.0
+    hooks:
+      - id: isort
+
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v3.4.0
+    hooks:
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+      - id: debug-statements
+
+  - repo: https://github.com/mgedmin/check-manifest
+    rev: "0.46"
+    hooks:
+      - id: check-manifest
+        args: [--no-build-isolation]

CODE_OF_CONDUCT.md

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+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as contributors and maintainers pledge to making participation in our project and our community a harassment-free experience for everyone, regardless of age, body size, disability, ethnicity, gender identity and expression, level of experience, nationality, personal appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable behavior and are expected to take appropriate and fair corrective action in response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or reject comments, commits, code, wiki edits, issues, and other contributions that are not aligned to this Code of Conduct, or to ban temporarily or permanently any contributor for other behaviors that they deem inappropriate, threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies both within project spaces and in public spaces when an individual is representing the project or its community. Examples of representing a project or community include using an official project e-mail address, posting via an official social media account, or acting as an appointed representative at an online or offline event. Representation of a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting the project team at ajitomi@gmail.com. The project team will review and investigate all complaints, and will respond in a way that it deems appropriate to the circumstances. The project team is obligated to maintain confidentiality with regard to the reporter of an incident. Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good faith may face temporary or permanent repercussions as determined by other members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4, available at [https://www.contributor-covenant.org/version/1/4/code-of-conduct.html][version]
+
+[homepage]: https://www.contributor-covenant.org/
+[version]: https://www.contributor-covenant.org/version/1/4/code-of-conduct.html

MANIFEST.in

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+include CHANGES.rst
+include LICENSE
+include tox.ini
+graft docs
+prune docs/_build
+graft tests
+global-exclude *.py[co]
+recursive-exclude * __pycache__

README.md

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-# python-cwt
-A Python implementation of CWT/COSE.
+# Python CWT
+
+A Python (>= 3.6) implementation of CBOR Web Token (CWT) and CBOR Object Signing and Encryption (COSE) compliant with:
+- [RFC8392: CBOR Web Token (CWT)](https://tools.ietf.org/html/rfc8392)
+- [RFC8152: CBOR Object Signing and Encryption (COSE)](https://tools.ietf.org/html/rfc8152)
+
+## Installing
+
+Install with pip after cloning this repository.
+
+```
+pip install .
+```
+
+## Usase
+
+Python CWT is easy to use.
+If you already know about [JSON Web Token (JWT)](https://tools.ietf.org/html/rfc7519),
+little knowledge of [CBOR](https://tools.ietf.org/html/rfc7049), [COSE](https://tools.ietf.org/html/rfc8152)
+and [CWT](https://tools.ietf.org/html/rfc8392) is required to use this library.
+
+Followings are basic examples which create CWT, verify and decode it:
+
+- [MACed CWT](#maced-cwt)
+- [Signed CWT](#signed-cwt)
+- [Encrypted CWT](#encrypted-cwt)
+- [Nested CWT](#nested-cwt)
+
+### MACed CWT
+
+Create a MACed CWT, verify and decode it as follows:
+
+```py
+import cwt
+from cwt import cose_key, claims
+
+key = cose_key.from_symmetric_key("mysecretpassword")  # "HMAC256/256" is the default algorithm.
+encoded = cwt.encode_and_mac(claims.from_json({"iss":"https://as.example", "sub":"dajiaji", "cti":"123"}), key)
+decoded = cwt.decode(encoded, key)
+```
+
+CBOR-like structure (Dict[int, Any]) can be used as follows:
+
+```py
+import cwt
+
+key = cwt.cose_key.from_symmetric_key("mysecretpassword")
+encoded = cwt.encode_and_mac({1:"https://as.example", 2:"dajiaji", 7:b"123"}, key)
+decoded = cwt.decode(encoded, key)
+```
+
+### Signed CWT
+
+Create an ECDSA (with SHA-256) key pair:
+
+```sh
+$ openssl ecparam -genkey -name prime256v1 -noout -out private_key.pem
+$ openssl ec -in private_key.pem -pubout -out public_key.pem
+```
+
+Create a Signed CWT, verify and decode it with the key pair  as follows:
+
+```py
+import cwt
+from cwt import cose_key, claims
+
+# Load PEM-formatted keys as COSE keys.
+with open("./private_key.pem") as key_file:
+    private_key = cose_key.from_pem(key_file.read())
+with open("./public_key.pem") as key_file:
+    public_key = cose_key.from_pem(key_file.read())
+
+# Encode with ES256 signing.
+encoded = cwt.encode_and_sign(
+    claims.from_json({"iss":"https://as.example", "sub":"dajiaji", "cti":"123"}), private_key)
+
+# Verify and decode.
+decoded = cwt.decode(encoded, public_key)
+```
+
+### Encrypted CWT
+
+Create an Ed25519 key pair:
+
+```sh
+$ openssl genpkey -algorithm ed25519 -out private_key.pem
+$ openssl pkey -in private_key.pem -pubout -out public_key.pem
+```
+
+Create an Encrypted CWT, verify and decode it with the key pair  as follows:
+
+```py
+import cwt
+from cwt import cose_key, claims
+
+# Load PEM-formatted keys as COSE keys.
+with open("./private_key.pem") as key_file:
+    private_key = cose_key.from_pem(key_file.read())
+with open("./public_key.pem") as key_file:
+    public_key = cose_key.from_pem(key_file.read())
+
+# Encode with ES256 encryption.
+encoded = cwt.encode_and_encrypt(
+    claims.from_json({"iss":"https://as.example", "sub":"dajiaji", "cti":"123"}), private_key)
+
+# Verify and decode.
+decoded = cwt.decode(encoded, public_key)
+```
+
+## Tests
+
+You can run tests from the project root after cloning with:
+
+```sh
+$ tox
+```

cwt/__init__.py

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+from .claims import Claims, claims
+from .cose import COSE
+from .cwt import CWT, decode, encode_and_encrypt, encode_and_mac, encode_and_sign
+from .exceptions import PyCWTDecodeError, PyCWTEncodeError, PyCWTError
+from .key_builder import KeyBuilder, cose_key
+
+__version__ = "0.1.0"
+__title__ = "Python CWT"
+__description__ = "A Python implementation of CWT/COSE"
+__url__ = "https://python-cwt.readthedocs.io"
+__uri__ = __url__
+__doc__ = __description__ + " <" + __uri__ + ">"
+__author__ = "AJITOMI Daisuke"
+__email__ = "ajitomi@gmail.com"
+__license__ = "MIT"
+__copyright__ = "Copyright 2021 AJITOMI Daisuke"
+__all__ = [
+    "CWT",
+    "encode_and_mac",
+    "encode_and_sign",
+    "encode_and_encrypt",
+    "decode",
+    "COSE",
+    "KeyBuilder",
+    "cose_key",
+    "Claims",
+    "claims",
+    "PyCWTError",
+    "PyCWTEncodeError",
+    "PyCWTDecodeError",
+]

cwt/claims.py

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+import json
+from typing import Any, Dict, Optional, Union
+
+
+class Claims:
+    """"""
+
+    REGISTERED_NAMES = {
+        "iss": 1,  # text string
+        "sub": 2,  # text string
+        "aud": 3,  # text string
+        "exp": 4,  # integer or floating-point number
+        "nbf": 5,  # integer or floating-point number
+        "iat": 6,  # integer or floating-point number
+        "cti": 7,  # byte string
+    }
+
+    def __init__(self, options: Optional[Dict[str, Any]] = None):
+        """"""
+        self._options = options
+        return
+
+    def from_json(self, claims: Union[str, bytes, Dict[str, Any]]) -> Dict[int, Any]:
+        """"""
+        json_claims: Dict[str, Any]
+        if isinstance(claims, str) or isinstance(claims, bytes):
+            json_claims = json.loads(claims)
+        else:
+            json_claims = claims
+
+        for k in json_claims:
+            if not isinstance(k, int):
+                break
+            ValueError("It is already CBOR-like format.")
+
+        # Convert JSON to CBOR (Convert the type of key from str to int).
+        cbor_claims = {}
+        for k, v in json_claims.items():
+            if k not in Claims.REGISTERED_NAMES:
+                # TODO Support additional arguments.
+                continue
+            cbor_claims[Claims.REGISTERED_NAMES[k]] = v
+        if 7 in cbor_claims and isinstance(cbor_claims[7], str):
+            cbor_claims[7] = cbor_claims[7].encode("utf-8")
+        return cbor_claims
+
+
+# export
+claims = Claims()

cwt/const.py

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+COSE_KEY_TYPES = {
+    "OKP": 1,  # OCtet Key Pair
+    "EC2": 2,  # Elliptic Curve Keys w/ x- and y-coordinate pair
+    "RSA": 3,  # RSA Key
+    "Symmetric": 4,  # Symmetric Keys
+    "HSS-LMS": 5,  # Public key for HSS/LMS hash-based digital signature
+    "WalnutDSA": 6,  # WalnutDSA public key
+}
+
+# COSE Algorithms for Content Encryption Key (CEK).
+COSE_ALGORITHMS_CEK = {
+    "A128GCM": 1,  # AES-GCM mode w/ 128-bit key, 128-bit tag
+    "A192GCM": 2,  # AES-GCM mode w/ 192-bit key, 128-bit tag
+    "A256GCM": 3,  # AES-GCM mode w/ 256-bit key, 128-bit tag
+    # etc.
+}
+
+# COSE Algorithms for MAC.
+COSE_ALGORITHMS_MAC = {
+    "HMAC256/64": 4,  # HMAC w/ SHA-256 truncated to 64 bits
+    "HMAC256/256": 5,  # HMAC w/ SHA-256
+    "HMAC384/384": 6,  # HMAC w/ SHA-384
+    "HMAC512/512": 7,  # HMAC w/ SHA-512
+    "AES-MAC128/64": 14,  # AES-MAC 128-bit key, 64-bit tag
+    "AES-MAC256/64": 15,  # AES-MAC 256-bit key, 64-bit tag
+    "AES-MAC128/128": 25,  # AES-MAC 128-bit key, 128-bit tag
+    "AES-MAC256/128": 26,  # AES-MAC 256-bit key, 128-bit tag
+    # etc.
+}
+
+# COSE Algorithms for Symmetric Keys.
+COSE_ALGORITHMS_SYMMETRIC = dict(COSE_ALGORITHMS_MAC, **COSE_ALGORITHMS_CEK)