Source code for django_ca.models

# This file is part of django-ca (https://github.com/mathiasertl/django-ca).
#
# django-ca is free software: you can redistribute it and/or modify it under the terms of the GNU
# General Public License as published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# django-ca is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
# even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License along with django-ca.  If not,
# see <http://www.gnu.org/licenses/>.

"""Django models for the django-ca application.

.. seealso:: https://docs.djangoproject.com/en/dev/topics/db/models/
"""

import base64
import hashlib
import itertools
import json
import logging
import random
import re
import typing
import warnings
from datetime import datetime
from datetime import timedelta
from datetime import timezone as tz
from typing import Dict
from typing import Iterable
from typing import List
from typing import Optional
from typing import Tuple
from typing import Union
from typing import cast

import josepy as jose
from acme import challenges
from acme import messages

from cryptography import x509
from cryptography.hazmat.primitives import hashes
from cryptography.hazmat.primitives import serialization
from cryptography.hazmat.primitives.asymmetric import dh
from cryptography.hazmat.primitives.asymmetric import dsa
from cryptography.hazmat.primitives.asymmetric import ec
from cryptography.hazmat.primitives.asymmetric import ed448
from cryptography.hazmat.primitives.asymmetric import x448
from cryptography.hazmat.primitives.asymmetric import x25519
from cryptography.hazmat.primitives.serialization import Encoding
from cryptography.hazmat.primitives.serialization import PrivateFormat
from cryptography.hazmat.primitives.serialization import PublicFormat
from cryptography.hazmat.primitives.serialization import load_pem_private_key
from cryptography.x509.oid import AuthorityInformationAccessOID
from cryptography.x509.oid import ExtensionOID
from cryptography.x509.oid import NameOID

from django.conf import settings
from django.core.cache import cache
from django.core.exceptions import ValidationError
from django.core.files.base import ContentFile
from django.core.validators import URLValidator
from django.db import models
from django.http import HttpRequest
from django.urls import reverse
from django.utils import timezone
from django.utils.crypto import get_random_string
from django.utils.functional import cached_property
from django.utils.text import slugify
from django.utils.translation import gettext_lazy as _

from . import ca_settings
from .acme.constants import BASE64_URL_ALPHABET
from .acme.constants import IdentifierType
from .acme.constants import Status
from .constants import ReasonFlags
from .deprecation import RemovedInDjangoCA122Warning
from .extensions import OID_TO_EXTENSION
from .extensions import AuthorityInformationAccess
from .extensions import AuthorityKeyIdentifier
from .extensions import BasicConstraints
from .extensions import CertificatePolicies
from .extensions import CRLDistributionPoints
from .extensions import ExtendedKeyUsage
from .extensions import FreshestCRL
from .extensions import InhibitAnyPolicy
from .extensions import IssuerAlternativeName
from .extensions import KeyUsage
from .extensions import NameConstraints
from .extensions import OCSPNoCheck
from .extensions import PolicyConstraints
from .extensions import PrecertificateSignedCertificateTimestamps
from .extensions import PrecertPoison
from .extensions import SubjectAlternativeName
from .extensions import SubjectKeyIdentifier
from .extensions import TLSFeature
from .extensions import get_extension_name
from .extensions.base import Extension
from .managers import AcmeAccountManager
from .managers import AcmeAuthorizationManager
from .managers import AcmeCertificateManager
from .managers import AcmeChallengeManager
from .managers import AcmeOrderManager
from .managers import CertificateAuthorityManager
from .managers import CertificateManager
from .modelfields import CertificateField
from .modelfields import CertificateSigningRequestField
from .modelfields import LazyCertificate
from .openssh import SshHostCaExtension
from .openssh import SshUserCaExtension
from .profiles import profiles
from .querysets import AcmeAccountQuerySet
from .querysets import AcmeAuthorizationQuerySet
from .querysets import AcmeCertificateQuerySet
from .querysets import AcmeChallengeQuerySet
from .querysets import AcmeOrderQuerySet
from .querysets import CertificateAuthorityQuerySet
from .querysets import CertificateQuerySet
from .signals import post_revoke_cert
from .signals import pre_revoke_cert
from .typehints import Expires
from .typehints import ExtensionTypeTypeVar
from .typehints import Literal
from .typehints import ParsableHash
from .typehints import ParsableKeyType
from .typehints import ParsableValue
from .typehints import PrivateKeyTypes
from .typehints import SerializedValue
from .utils import bytes_to_hex
from .utils import ca_storage
from .utils import classproperty
from .utils import format_name
from .utils import generate_private_key
from .utils import get_crl_cache_key
from .utils import int_to_hex
from .utils import multiline_url_validator
from .utils import parse_encoding
from .utils import parse_expires
from .utils import parse_general_name
from .utils import parse_hash_algorithm
from .utils import parse_key_curve
from .utils import read_file
from .utils import validate_key_parameters

log = logging.getLogger(__name__)

_UNSUPPORTED_PRIVATE_KEY_TYPES = (
    dh.DHPrivateKey,
    ed448.Ed448PrivateKey,
    x25519.X25519PrivateKey,
    x448.X448PrivateKey,
)


def acme_slug() -> str:
    """Default function to get an ACME conforming slug."""
    return get_random_string(length=12)


def acme_order_expires() -> datetime:
    """Default function for the expiry of an ACME order."""
    return timezone.now() + ca_settings.ACME_ORDER_VALIDITY


def acme_token() -> str:
    """Generate an ACME token for this challenge.

    Note that currently all challenges have the same requirements on tokens, except for DNS challenges
    which seem to allow padding ("=") characters. We ignore the '=' for DNS challenges as our tokens are
    already longer then required.
    """
    return get_random_string(64, allowed_chars=BASE64_URL_ALPHABET)


def validate_past(value: datetime) -> None:
    """Validate that a given datetime is not in the future."""
    if value > timezone.now():
        raise ValidationError(_("Date must be in the past!"))


def json_validator(value: Union[str, bytes, bytearray]) -> None:
    """Validated that the given data is valid JSON."""
    try:
        json.loads(value)
    except Exception as e:
        raise ValidationError(_("Must be valid JSON: %(message)s") % {"message": str(e)}) from e


def pem_validator(value: str) -> None:
    """Validator that ensures a value is a valid PEM public certificate."""

    if not value.startswith("-----BEGIN PUBLIC KEY-----\n"):
        raise ValidationError(_("Not a valid PEM."))
    if not value.endswith("\n-----END PUBLIC KEY-----"):
        raise ValidationError(_("Not a valid PEM."))


class DjangoCAModel(models.Model):
    """Abstract base model for all django-ca models."""

    class Meta:
        abstract = True

    @classproperty
    def admin_add_url(cls) -> str:  # pylint: disable=no-self-argument; false positive
        """URL to add an instance in the admin interface."""
        return reverse(f"admin:{cls._meta.app_label}_{cls._meta.model_name}_add")

    @classproperty
    def admin_changelist_url(cls) -> str:  # pylint: disable=no-self-argument; false positive
        """Changelist URL in the admin interface for the model."""
        return reverse(f"admin:{cls._meta.app_label}_{cls._meta.model_name}_changelist")

    @property
    def admin_change_url(self) -> str:
        """Change URL in the admin interface for the model instance."""
        return reverse(f"admin:{self._meta.app_label}_{self._meta.model_name}_change", args=(self.pk,))


[docs]class Watcher(models.Model): """A watcher represents an email address that will receive notifications about expiring certificates.""" name = models.CharField(max_length=64, blank=True, default="", verbose_name=_("CommonName")) mail = models.EmailField(verbose_name=_("E-Mail"), unique=True)
[docs] @classmethod def from_addr(cls, addr: str) -> "Watcher": """Class constructor that creates an instance from an email address.""" name = "" match = re.match(r"(.*?)\s*<(.*)>", addr) if match is not None: name, addr = match.groups() try: watcher = cls.objects.get(mail=addr) if watcher.name != name: watcher.name = name watcher.save() except cls.DoesNotExist: watcher = cls(mail=addr, name=name) watcher.full_clean() watcher.save() return watcher
def __str__(self) -> str: if self.name: return f"{self.name} <{self.mail}>" return self.mail
[docs]class X509CertMixin(DjangoCAModel): """Mixin class with common attributes for Certificates and Certificate Authorities.""" # pylint: disable=too-many-instance-attributes,too-many-public-methods # X.509 certificates are complex. Sorry. # reasons are defined in http://www.ietf.org/rfc/rfc3280.txt REVOCATION_REASONS = ( (ReasonFlags.aa_compromise.name, _("Attribute Authority compromised")), (ReasonFlags.affiliation_changed.name, _("Affiliation changed")), (ReasonFlags.ca_compromise.name, _("CA compromised")), (ReasonFlags.certificate_hold.name, _("On Hold")), (ReasonFlags.cessation_of_operation.name, _("Cessation of operation")), (ReasonFlags.key_compromise.name, _("Key compromised")), (ReasonFlags.privilege_withdrawn.name, _("Privilege withdrawn")), (ReasonFlags.remove_from_crl.name, _("Removed from CRL")), (ReasonFlags.superseded.name, _("Superseded")), (ReasonFlags.unspecified.name, _("Unspecified")), ) created = models.DateTimeField(auto_now=True) valid_from = models.DateTimeField(blank=False) expires = models.DateTimeField(null=False, blank=False) pub = CertificateField(verbose_name=_("Public key")) cn = models.CharField(max_length=128, verbose_name=_("CommonName")) serial = models.CharField(max_length=64, unique=True) # revocation information revoked = models.BooleanField(default=False) revoked_date = models.DateTimeField( null=True, blank=True, verbose_name=_("Revoked on"), validators=[validate_past] ) revoked_reason = models.CharField( max_length=32, blank=True, default="", verbose_name=_("Reason for revokation"), choices=REVOCATION_REASONS, ) compromised = models.DateTimeField( null=True, blank=True, verbose_name=_("Date of compromise"), validators=[validate_past], help_text=_("Optional: When this certificate was compromised. You can change this date later."), ) _x509 = None class Meta: abstract = True @property def bundle_as_pem(self) -> str: """Get the bundle as PEM.""" # TYPE NOTE: bundle is defined in base class but returns a list (considered invariant by mypy). This # means that an abstract "bundle" property here could not be correctly typed. return "".join(c.pub.pem for c in self.bundle) # type: ignore[attr-defined]
[docs] def get_revocation_reason(self) -> Optional[x509.ReasonFlags]: """Get the revocation reason of this certificate.""" if self.revoked is False: return None return x509.ReasonFlags[self.revoked_reason]
[docs] def get_compromised_time(self) -> Optional[datetime]: """Return when this certificate was compromised as a *naive* datetime. Returns ``None`` if the time is not known **or** if the certificate is not revoked. """ if self.revoked is False or self.compromised is None: return None if timezone.is_aware(self.compromised): # convert datetime object to UTC and make it naive return timezone.make_naive(self.compromised, tz.utc) return self.compromised
[docs] def get_revocation_time(self) -> Optional[datetime]: """Get the revocation time as naive datetime.""" if self.revoked is False: return None if self.revoked_date is None: log.warning("Inconsistent model state: revoked=True and revoked_date=None.") return None if timezone.is_aware(self.revoked_date): # convert datetime object to UTC and make it naive return timezone.make_naive(self.revoked_date, tz.utc) return self.revoked_date
[docs] def update_certificate(self, value: x509.Certificate) -> None: """Update this instance with data from a :py:class:`cg:cryptography.x509.Certificate`. This function will also populate the `cn`, `serial, `expires` and `valid_from` fields. """ self.pub = LazyCertificate(value) self.cn = next( # pylint: disable=invalid-name (attr.value for attr in value.subject if attr.oid == NameOID.COMMON_NAME), "" # type: ignore ) self.expires = self.not_after self.valid_from = self.not_before if settings.USE_TZ: self.expires = timezone.make_aware(self.expires, timezone=tz.utc) self.valid_from = timezone.make_aware(self.valid_from, timezone=tz.utc) self.serial = int_to_hex(value.serial_number)
########################## # Certificate properties # ########################## @property def algorithm(self) -> Optional[hashes.HashAlgorithm]: """A shortcut for :py:attr:`~cg:cryptography.x509.Certificate.signature_hash_algorithm`.""" return self.pub.loaded.signature_hash_algorithm
[docs] def get_digest(self, algo: ParsableHash) -> str: """Get the fingerprint for this certificate. .. deprecated:: 1.21.0 Use :py:func:`~django_ca.models.X509CertMixin.get_fingerprint` instead. """ warnings.warn( "get_digest() is deprecated, use get_fingerprint() instead", category=RemovedInDjangoCA122Warning, stacklevel=1, ) return self.get_fingerprint(parse_hash_algorithm(algo))
[docs] def get_fingerprint(self, algorithm: hashes.HashAlgorithm) -> str: """Get the digest for a certificate as string, including colons.""" return bytes_to_hex(self.pub.loaded.fingerprint(algorithm))
[docs] def get_filename(self, ext: str, bundle: bool = False) -> str: """Get a filename safe for any file system and OS for this certificate based on the common name. Parameters ---------- ext : str The filename extension to use (e.g. ``"pem"``). bundle : bool, optional Adds "_bundle" as suffix. """ slug = slugify(self.cn.replace(".", "_")) if bundle is True: return f"{slug}_bundle.{ext.lower()}" return f"{slug}.{ext.lower()}"
[docs] def get_revocation(self) -> x509.RevokedCertificate: """Get the `RevokedCertificate` instance for this certificate for CRLs. This function is just a shortcut for :py:class:`~cg:cryptography.x509.RevokedCertificateBuilder`. .. seealso:: :py:class:`~cg:cryptography.x509.CertificateRevocationListBuilder`. Raises ------ ValueError If the certificate is not revoked. Returns ------- :py:class:`~cg:cryptography.x509.RevokedCertificate` """ if self.revoked is False: raise ValueError("Certificate is not revoked.") if self.revoked_date is None: raise ValueError("Certificate has no revocation date") revoked_cert = ( x509.RevokedCertificateBuilder() .serial_number(self.pub.loaded.serial_number) .revocation_date(self.revoked_date) ) reason = self.get_revocation_reason() if reason != x509.ReasonFlags.unspecified and reason is not None: # RFC 5270, 5.3.1: "reason code CRL entry extension SHOULD be absent instead of using the # unspecified (0) reasonCode value" revoked_cert = revoked_cert.add_extension(x509.CRLReason(reason), critical=False) compromised = self.get_compromised_time() if compromised: # RFC 5280, 5.3.2 says that this extension MUST be non-critical revoked_cert = revoked_cert.add_extension(x509.InvalidityDate(compromised), critical=False) return revoked_cert.build()
@property def hpkp_pin(self) -> str: """The HPKP public key pin for this certificate. Inspired by https://github.com/luisgf/hpkp-python/blob/master/hpkp.py. .. seealso:: https://en.wikipedia.org/wiki/HTTP_Public_Key_Pinning """ public_key_raw = self.pub.loaded.public_key().public_bytes( encoding=Encoding.DER, format=PublicFormat.SubjectPublicKeyInfo ) public_key_hash = hashlib.sha256(public_key_raw).digest() return base64.b64encode(public_key_hash).decode("utf-8") @property def issuer(self) -> x509.Name: """The certificate issuer field as :py:class:`~cg:cryptography.x509.Name`. .. versionchanged:: 1.20.0 This property was a :py:class:`~django_ca.subject.Subject` before ``django-ca==1.20.0``. """ return self.pub.loaded.issuer @property def jwk(self) -> typing.Union[jose.jwk.JWKRSA, jose.jwk.JWKEC]: """Get a JOSE JWK public key for this certificate.""" pkey = self.pub.loaded.public_key() jwk = jose.jwk.JWK.load(pkey.public_bytes(Encoding.DER, PublicFormat.SubjectPublicKeyInfo)) # JWK.load() may return a private instead, so we rule this out here for type safety. This branch # should normally not happen. if not isinstance(jwk, (jose.jwk.JWKRSA, jose.jwk.JWKEC)): # pragma: no cover raise TypeError(f"Loading JWK RSA key returned {type(jwk)}.") return jwk @property def not_before(self) -> datetime: """Date/Time this certificate was created""" return self.pub.loaded.not_valid_before @property def not_after(self) -> datetime: """Date/Time this certificate expires.""" return self.pub.loaded.not_valid_after
[docs] def revoke( self, reason: ReasonFlags = ReasonFlags.unspecified, compromised: Optional[datetime] = None ) -> None: """Revoke the current certificate. This function emits the ``pre_revoke_cert`` and ``post_revoke_cert`` signals. Parameters ---------- reason : :py:class:`~django_ca.constants.ReasonFlags`, optional The reason for revocation, defaults to ``ReasonFlags.unspecified``. compromised : datetime, optional When this certificate was compromised. """ pre_revoke_cert.send(sender=self.__class__, cert=self, reason=reason) self.revoked = True self.revoked_date = timezone.now() self.revoked_reason = reason.name self.compromised = compromised self.save() post_revoke_cert.send(sender=self.__class__, cert=self)
@property def subject(self) -> x509.Name: """The certificate subject field as :py:class:`~cg:cryptography.x509.Name`. .. versionchanged:: 1.20.0 This property was a :py:class:`~django_ca.subject.Subject` before ``django-ca==1.20.0``. """ return self.pub.loaded.subject @property def distinguished_name(self) -> str: """The certificates distinguished name formatted as string.""" return format_name(self.pub.loaded.subject) ################### # X509 extensions # ################### @cached_property def _x509_extensions(self) -> Dict[x509.ObjectIdentifier, "x509.Extension[x509.ExtensionType]"]: return {e.oid: e for e in self.pub.loaded.extensions} @cached_property def _sorted_extensions(self) -> List["x509.Extension[x509.ExtensionType]"]: # NOTE: We need the dotted_string in the sort key if we have multiple unknown extensions, which then # show up as "Unknown OID" and have to be sorted by oid return list(sorted(self._x509_extensions.values(), key=lambda e: get_extension_name(e.oid))) @cached_property def extensions( self, ) -> List[ typing.Union[ Extension[ExtensionTypeTypeVar, ParsableValue, SerializedValue], "x509.Extension[x509.ExtensionType]", ] ]: """List of all extensions for this certificate.""" exts = [] for ext in self._sorted_extensions: if ext.oid in OID_TO_EXTENSION: exts.append(getattr(self, OID_TO_EXTENSION[ext.oid].key)) # extension that does not support new extension framework else: exts.append(ext) return exts @cached_property def authority_information_access(self) -> Optional[AuthorityInformationAccess]: """The :py:class:`~django_ca.extensions.AuthorityInformationAccess` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.AuthorityInformationAccess) except x509.ExtensionNotFound: return None return AuthorityInformationAccess(ext) @cached_property def authority_key_identifier(self) -> Optional[AuthorityKeyIdentifier]: """The :py:class:`~django_ca.extensions.AuthorityKeyIdentifier` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.AuthorityKeyIdentifier) except x509.ExtensionNotFound: return None return AuthorityKeyIdentifier(ext) @cached_property def basic_constraints(self) -> Optional[BasicConstraints]: """The :py:class:`~django_ca.extensions.BasicConstraints` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.BasicConstraints) except x509.ExtensionNotFound: return None return BasicConstraints(ext) @cached_property def crl_distribution_points(self) -> Optional[CRLDistributionPoints]: """The :py:class:`~django_ca.extensions.CRLDistributionPoints` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.CRLDistributionPoints) except x509.ExtensionNotFound: return None return CRLDistributionPoints(ext) @cached_property def certificate_policies(self) -> Optional[CertificatePolicies]: """The :py:class:`~django_ca.extensions.CertificatePolicies` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.CertificatePolicies) except x509.ExtensionNotFound: return None return CertificatePolicies(ext) @cached_property def freshest_crl(self) -> Optional[FreshestCRL]: """The :py:class:`~django_ca.extensions.FreshestCRL` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.FreshestCRL) except x509.ExtensionNotFound: return None return FreshestCRL(ext) @cached_property def inhibit_any_policy(self) -> Optional[InhibitAnyPolicy]: """The :py:class:`~django_ca.extensions.InhibitAnyPolicy` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.InhibitAnyPolicy) except x509.ExtensionNotFound: return None return InhibitAnyPolicy(ext) @cached_property def issuer_alternative_name(self) -> Optional[IssuerAlternativeName]: """The :py:class:`~django_ca.extensions.IssuerAlternativeName` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.IssuerAlternativeName) except x509.ExtensionNotFound: return None return IssuerAlternativeName(ext) @cached_property def policy_constraints(self) -> Optional[PolicyConstraints]: """The :py:class:`~django_ca.extensions.PolicyConstraints` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.PolicyConstraints) except x509.ExtensionNotFound: return None return PolicyConstraints(ext) @cached_property def key_usage(self) -> Optional[KeyUsage]: """The :py:class:`~django_ca.extensions.KeyUsage` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.KeyUsage) except x509.ExtensionNotFound: return None return KeyUsage(ext) @cached_property def extended_key_usage(self) -> Optional[ExtendedKeyUsage]: """The :py:class:`~django_ca.extensions.ExtendedKeyUsage` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.ExtendedKeyUsage) except x509.ExtensionNotFound: return None return ExtendedKeyUsage(ext) @cached_property def name_constraints(self) -> Optional[NameConstraints]: """The :py:class:`~django_ca.extensions.NameConstraints` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.NameConstraints) except x509.ExtensionNotFound: return None return NameConstraints(ext) @cached_property def ocsp_no_check(self) -> Optional[OCSPNoCheck]: """The :py:class:`~django_ca.extensions.OCSPNoCheck` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.OCSPNoCheck) except x509.ExtensionNotFound: return None return OCSPNoCheck(ext) @cached_property def precert_poison(self) -> Optional[PrecertPoison]: """The :py:class:`~django_ca.extensions.PrecertPoison` extension or ``None`` if not present.""" try: self.pub.loaded.extensions.get_extension_for_class(x509.PrecertPoison) except x509.ExtensionNotFound: return None return PrecertPoison() @cached_property def precertificate_signed_certificate_timestamps( self, ) -> Optional[PrecertificateSignedCertificateTimestamps]: """The :py:class:`~django_ca.extensions.PrecertificateSignedCertificateTimestamps` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class( x509.PrecertificateSignedCertificateTimestamps ) except x509.ExtensionNotFound: return None return PrecertificateSignedCertificateTimestamps(ext) @cached_property def subject_alternative_name(self) -> Optional[SubjectAlternativeName]: """The :py:class:`~django_ca.extensions.SubjectAlternativeName` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.SubjectAlternativeName) except x509.ExtensionNotFound: return None return SubjectAlternativeName(ext) @cached_property def subject_key_identifier(self) -> Optional[SubjectKeyIdentifier]: """The :py:class:`~django_ca.extensions.SubjectKeyIdentifier` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.SubjectKeyIdentifier) except x509.ExtensionNotFound: return None return SubjectKeyIdentifier(ext) @cached_property def tls_feature(self) -> Optional[TLSFeature]: """The :py:class:`~django_ca.extensions.TLSFeature` extension or ``None`` if not present.""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.TLSFeature) except x509.ExtensionNotFound: return None return TLSFeature(ext)
[docs]class CertificateAuthority(X509CertMixin): """Model representing a x509 Certificate Authority.""" objects: CertificateAuthorityManager = CertificateAuthorityManager.from_queryset( CertificateAuthorityQuerySet )() name = models.CharField(max_length=32, help_text=_("A human-readable name"), unique=True) """Human-readable name of the CA, only used for displaying the CA.""" enabled = models.BooleanField(default=True) parent = models.ForeignKey( "self", on_delete=models.SET_NULL, null=True, blank=True, related_name="children" ) private_key_path = models.CharField(max_length=256, help_text=_("Path to the private key.")) # various details used when signing certs crl_url = models.TextField( blank=True, default="", validators=[multiline_url_validator], verbose_name=_("CRL URLs"), help_text=_("URLs, one per line, where you can retrieve the CRL."), ) crl_number = models.TextField( default='{"scope": {}}', blank=True, verbose_name=_("CRL Number"), validators=[json_validator], help_text=_("Data structure to store the CRL number (see RFC 5280, 5.2.3) depending on the scope."), ) issuer_url = models.URLField( blank=True, null=True, verbose_name=_("Issuer URL"), help_text=_("URL to the certificate of this CA (in DER format)."), ) ocsp_url = models.URLField( blank=True, null=True, verbose_name=_("OCSP responder URL"), help_text=_("URL of a OCSP responser for the CA."), ) issuer_alt_name = models.CharField( blank=True, max_length=255, default="", verbose_name=_("issuerAltName"), help_text=_("URL for your CA."), ) caa_identity = models.CharField( blank=True, max_length=32, verbose_name=_("CAA identity"), help_text=_("CAA identity for this CA (NOTE: Not currently used!)."), ) website = models.URLField(blank=True, help_text=_("Website for your CA.")) terms_of_service = models.URLField( blank=True, verbose_name="Terms of Service", help_text=_("URL to Terms of Service for this CA") ) # ACMEv2 fields acme_enabled = models.BooleanField( default=False, verbose_name=_("Enable ACME"), help_text=_("Whether it is possible to use ACME for this CA."), ) acme_requires_contact = models.BooleanField( default=True, verbose_name="Requires contact", help_text=_("If this CA requires a contact address during account registration."), ) # CAA record and website are general fields _key = None
[docs] def key(self, password: Optional[Union[str, bytes]] = None) -> PrivateKeyTypes: """The CAs private key as private key. .. seealso:: :py:func:`~cg:cryptography.hazmat.primitives.serialization.load_pem_private_key`. """ if isinstance(password, str): password = password.encode("utf-8") if self._key is None: key_data = read_file(self.private_key_path) try: self._key = load_pem_private_key(key_data, password) except ValueError as ex: # cryptography passes the OpenSSL error directly here and it is notoriously unstable. raise ValueError("Could not decrypt private key - bad password?") from ex if isinstance(self._key, _UNSUPPORTED_PRIVATE_KEY_TYPES): # pragma: no cover raise ValueError("Private key of this type is not supported.") return self._key
@property def key_exists(self) -> bool: """``True`` if the private key is locally accessible.""" if self._key is not None: return True return ca_storage.exists(self.private_key_path)
[docs] def cache_crls( # pylint: disable=too-many-locals self, password: Optional[Union[str, bytes]] = None, algorithm: ParsableHash = None ) -> None: """Function to cache all CRLs for this CA.""" password = password or self.get_password() ca_key = self.key(password) if isinstance(ca_key, dsa.DSAPrivateKey) and algorithm is None: algorithm = hashes.SHA1() elif algorithm is not None: algorithm = parse_hash_algorithm(algorithm) for config in ca_settings.CA_CRL_PROFILES.values(): overrides = config.get("OVERRIDES", {}).get(self.serial, {}) if overrides.get("skip"): continue algorithm = algorithm or parse_hash_algorithm(overrides.get("algorithm", config.get("algorithm"))) expires = overrides.get("expires", config.get("expires", 86400)) scope = overrides.get("scope", config.get("scope")) full_name = overrides.get("full_name", config.get("full_name")) relative_name = overrides.get("relative_name", config.get("relative_name")) encodings = overrides.get( "encodings", config.get( "encodings", [ "DER", ], ), ) crl = None # only compute crl when it is actually needed for encoding in encodings: encoding = parse_encoding(encoding) cache_key = get_crl_cache_key(self.serial, algorithm, encoding, scope=scope) if expires >= 600: # pragma: no branch # for longer expiries we substract a random value so that regular CRL regeneration is # distributed a bit cache_expires = expires - random.randint(1, 5) * 60 if cache.get(cache_key) is None: if crl is None: crl = self.get_crl( expires=expires, algorithm=algorithm, password=password, scope=scope, full_name=full_name, relative_name=relative_name, ) encoded_crl = crl.public_bytes(encoding) cache.set(cache_key, encoded_crl, cache_expires)
[docs] def generate_ocsp_key( self, profile: str = "ocsp", expires: Expires = 3, algorithm: ParsableHash = None, password: Optional[Union[str, bytes]] = None, key_size: Optional[int] = None, key_type: ParsableKeyType = "RSA", ecc_curve: Optional[ec.EllipticCurve] = None, autogenerated: bool = True, ) -> Tuple[str, str, "Certificate"]: """Generate OCSP keys for this CA. .. deprecated:: 1.20.0 Passing unparsed values is deprecated and will be removed in ``django_ca==1.22``. This affects the following parameters: * Passing a ``str`` for ``ecc_curve``. Parameters ---------- profile : str, optional The profile to use for generating the certificate. The default is ``"ocsp"``. expires : int or datetime, optional Number of days or datetime when this certificate expires. The default is ``3`` (OCSP certificates are usually renewed frequently). algorithm : str, optional Passed to :py:func:`~django_ca.utils.parse_hash_algorithm` and defaults to :ref:`CA_DIGEST_ALGORITHM <settings-ca-digest-algorithm>`. password : bytes, optional The password to the CA as bytes, if its private key is encrypted. key_size : int, optional The key size of the private key, defaults to :ref:`CA_DEFAULT_KEY_SIZE <settings-ca-default-key-size>`. key_type : {"RSA", "DSA", "ECC", "EdDSA", "Ed448"}, optional The private key type to use, the default is ``"RSA"``. ecc_curve : :py:class:`~cg:cryptography.hazmat.primitives.asymmetric.ec.EllipticCurve`, optional An elliptic curve to use for ECC keys. This parameter is ignored if ``key_type`` is not ``"ECC"``. Defaults to the :ref:`CA_DEFAULT_ECC_CURVE <settings-ca-default-ecc-curve>`. autogenerated : bool, optional Set the ``autogenerated`` flag of the certificate. ``True`` by default, since this method is usually invoked by regular cron jobs. """ # pylint: disable=too-many-arguments,too-many-locals # OCSP is pretty complex, there is no way to trim down the arguments w/o losing features. password = password or self.get_password() # DSA private keys can only sign DSA keys, hash algorithm for DSA keys must be SHA1 if isinstance(self.key(password), dsa.DSAPrivateKey): key_type = "DSA" if key_type == "DSA": algorithm = hashes.SHA1() if key_type == "ECC" and isinstance(ecc_curve, str): warnings.warn("Passing a str as ecc_curve is deprecated", category=RemovedInDjangoCA122Warning) ecc_curve = parse_key_curve(ecc_curve) validate_key_parameters(key_size, key_type, ecc_curve) expires = parse_expires(expires) algorithm = parse_hash_algorithm(algorithm) safe_serial = self.serial.replace(":", "") # generate the private key private_key = generate_private_key(key_size, key_type, ecc_curve) private_pem = private_key.private_bytes( encoding=Encoding.PEM, format=PrivateFormat.PKCS8, encryption_algorithm=serialization.NoEncryption(), ) private_path = ca_storage.generate_filename(f"ocsp/{safe_serial}.key") csr = ( x509.CertificateSigningRequestBuilder() .subject_name(self.pub.loaded.subject) .sign(private_key, hashes.SHA256()) ) # TODO: The subject we pass is just a guess - see what public CAs do!? pylint: disable=fixme # TODO: We never pass expires, we must add it and test the value cert = Certificate.objects.create_cert( ca=self, csr=csr, profile=profiles[profile], subject=self.subject, algorithm=algorithm, autogenerated=autogenerated, password=password, add_ocsp_url=False, ) cert_path = ca_storage.generate_filename(f"ocsp/{safe_serial}.pem") for path, contents in [(private_path, private_pem), (cert_path, cert.pub.pem.encode())]: if ca_storage.exists(path): with ca_storage.open(path, "wb") as stream: stream.write(contents) else: ca_storage.save(path, ContentFile(contents)) return private_path, cert_path, cert
[docs] def get_authority_information_access_extension( self, ) -> typing.Optional[x509.Extension[x509.AuthorityInformationAccess]]: """Get the AuthorityInformationAccess extension to use in certificates signed by this CA.""" if not self.issuer_url and not self.ocsp_url: return None descriptions = [] if self.issuer_url: descriptions.append( x509.AccessDescription( access_method=AuthorityInformationAccessOID.CA_ISSUERS, access_location=parse_general_name(self.issuer_url), ) ) if self.ocsp_url: descriptions.append( x509.AccessDescription( access_method=AuthorityInformationAccessOID.OCSP, access_location=parse_general_name(self.ocsp_url), ) ) value = x509.AuthorityInformationAccess(descriptions=descriptions) return x509.Extension(oid=ExtensionOID.AUTHORITY_INFORMATION_ACCESS, critical=False, value=value)
[docs] def get_authority_key_identifier(self) -> x509.AuthorityKeyIdentifier: """Return the AuthorityKeyIdentifier extension used in certificates signed by this CA.""" try: ski = self.pub.loaded.extensions.get_extension_for_class(x509.SubjectKeyIdentifier) except x509.ExtensionNotFound as ex: public_key = self.pub.loaded.public_key() if isinstance(public_key, _UNSUPPORTED_PRIVATE_KEY_TYPES): # pragma: no cover # COVERAGE NOTE: This does not happen in reality, we never generate keys of this type raise TypeError("Cannot get AuthorityKeyIdentifier from this private key type.") from ex # TYPE NOTE: mypy does not currently recognize isinstance() check above return x509.AuthorityKeyIdentifier.from_issuer_public_key(public_key) # type: ignore[arg-type] else: return x509.AuthorityKeyIdentifier.from_issuer_subject_key_identifier(ski.value)
[docs] def get_authority_key_identifier_extension(self) -> x509.Extension[x509.AuthorityKeyIdentifier]: """Get the AuthorityKeyIdentifier extension to use in certificates signed by this CA.""" return x509.Extension( critical=False, oid=ExtensionOID.AUTHORITY_KEY_IDENTIFIER, value=self.get_authority_key_identifier(), )
[docs] def get_crl_certs( self, scope: Literal[None, "ca", "user", "attribute"], now: datetime ) -> Iterable[X509CertMixin]: """Get CRLs for the given scope.""" ca_qs = self.children.filter(expires__gt=now).revoked() cert_qs = self.certificate_set.filter(expires__gt=now).revoked() if scope == "ca": return ca_qs if scope == "user": return cert_qs if scope == "attribute": return [] # not really supported if scope is None: return itertools.chain(ca_qs, cert_qs) raise ValueError('scope must be either None, "ca", "user" or "attribute"')
[docs] def get_crl( self, expires: int = 86400, algorithm: typing.Optional[hashes.HashAlgorithm] = None, password: Optional[Union[str, bytes]] = None, scope: Optional[Literal["ca", "user", "attribute"]] = None, counter: Optional[str] = None, full_name: Optional[typing.Iterable[x509.GeneralName]] = None, relative_name: Optional[x509.RelativeDistinguishedName] = None, ) -> x509.CertificateRevocationList: """Generate a Certificate Revocation List (CRL). The ``full_name`` and ``relative_name`` parameters describe how to retrieve the CRL and are used in the `Issuing Distribution Point extension <https://tools.ietf.org/html/rfc5280.html#section-5.2.5>`_. The former defaults to the ``crl_url`` field, pass ``None`` to not include the value. At most one of the two may be set. .. versionchanged:: 1.20.0 The ``full_name`` parameter must be a list of :py:class:`~cg:cryptography.x509.GeneralName`, ``str`` are no longer allowed. Parameters ---------- expires : int The time in seconds when this CRL expires. Note that you should generate a new CRL until then. algorithm : :class:`~cg:cryptography.hazmat.primitives.hashes.HashAlgorithm`, optional The hash algorithm to use, defaults to :ref:`CA_DIGEST_ALGORITHM <settings-ca-digest-algorithm>`. password : bytes, optional Password used to load the private key of the certificate authority. If not passed, the private key is assumed to be unencrypted. scope : {None, 'ca', 'user', 'attribute'}, optional What to include in the CRL: Use ``"ca"`` to include only revoked certificate authorities and ``"user"`` to include only certificates or ``None`` (the default) to include both. ``"attribute"`` is reserved for future use and always produces an empty CRL. counter : str, optional Override the counter-variable for the CRL Number extension. Passing the same key to multiple invocations will yield a different sequence then what would ordinarily be returned. The default is to use the scope as the key. full_name : list of :py:class:`~cg:cryptography.x509.GeneralName`, optional List of general names to use in the Issuing Distribution Point extension. If not passed, use ``crl_url`` if set. relative_name : :py:class:`~cg:cryptography.x509.RelativeDistinguishedName`, optional Used in Issuing Distribution Point extension, retrieve the CRL relative to the issuer. Returns ------- bytes The CRL in the requested format. """ # pylint: disable=too-many-statements,too-many-branches,too-many-locals,too-many-arguments # It's not easy to create a CRL. Sorry. now = now_builder = timezone.now() if algorithm is None: algorithm = ca_settings.CA_DIGEST_ALGORITHM if timezone.is_aware(now_builder): now_builder = timezone.make_naive(now, tz.utc) else: now_builder = datetime.utcnow() builder = x509.CertificateRevocationListBuilder() builder = builder.issuer_name(self.pub.loaded.subject) builder = builder.last_update(now_builder) builder = builder.next_update(now_builder + timedelta(seconds=expires)) parsed_full_name = None if full_name is not None: parsed_full_name = full_name # CRLs for root CAs with scope "ca" (or no scope - this includes CAs) do not sete a full_name in the # IssuingDistributionPoint extension by default. For full path validation with CRLs, the CRL is also # used for validating the Root CA (which does not contain a CRL Distribution Point). But the Full Name # in the CRL IDP and the CA CRL DP have to match. See also: # https://github.com/mathiasertl/django-ca/issues/64 elif scope in ("ca", None) and self.parent is None: parsed_full_name = None # If CA_DEFAULT_HOSTNAME is set, CRLs with scope "ca" add the same URL in the IssuingDistributionPoint # extension that is also added in the CRL Distribution Points extension for CAs issued by this CA. # See also: # https://github.com/mathiasertl/django-ca/issues/64 elif scope == "ca" and ca_settings.CA_DEFAULT_HOSTNAME: crl_path = reverse("django_ca:ca-crl", kwargs={"serial": self.serial}) parsed_full_name = [ x509.UniformResourceIdentifier(f"http://{ca_settings.CA_DEFAULT_HOSTNAME}{crl_path}") ] elif scope in ("user", None) and self.crl_url: crl_url = [url.strip() for url in self.crl_url.split()] parsed_full_name = [x509.UniformResourceIdentifier(c) for c in crl_url] # Keyword arguments for the IssuingDistributionPoint extension only_contains_attribute_certs = False only_contains_ca_certs = False only_contains_user_certs = False indirect_crl = False if scope == "ca": only_contains_ca_certs = True elif scope == "user": only_contains_user_certs = True elif scope == "attribute": # sorry, nothing we support right now only_contains_attribute_certs = True for cert in self.get_crl_certs(scope, now): builder = builder.add_revoked_certificate(cert.get_revocation()) # We can only add the IDP extension if one of these properties is set, see RFC 5280, 5.2.5. add_idp = ( only_contains_attribute_certs or only_contains_user_certs or only_contains_ca_certs or parsed_full_name or relative_name ) if add_idp: # pragma: no branch builder = builder.add_extension( x509.IssuingDistributionPoint( indirect_crl=indirect_crl, only_contains_attribute_certs=only_contains_attribute_certs, only_contains_ca_certs=only_contains_ca_certs, only_contains_user_certs=only_contains_user_certs, full_name=parsed_full_name, only_some_reasons=None, relative_name=relative_name, ), critical=True, ) # Add AuthorityKeyIdentifier from CA aki = self.get_authority_key_identifier() builder = builder.add_extension(aki, critical=False) # Add the CRLNumber extension (RFC 5280, 5.2.3) if counter is None: counter = scope or "all" crl_number_data = json.loads(self.crl_number) crl_number = int(crl_number_data["scope"].get(counter, 0)) builder = builder.add_extension(x509.CRLNumber(crl_number=crl_number), critical=False) # increase crl_number for the given scope and save crl_number_data["scope"][counter] = crl_number + 1 self.crl_number = json.dumps(crl_number_data) self.save() return builder.sign(private_key=self.key(password), algorithm=algorithm)
[docs] def get_password(self) -> Optional[str]: """Get password for the private key from the ``CA_PASSWORDS`` setting.""" return ca_settings.CA_PASSWORDS.get(self.serial)
@property def pathlen(self) -> Optional[int]: """The ``pathlen`` attribute of the ``BasicConstraints`` extension (either an ``int`` or ``None``).""" try: ext = self.pub.loaded.extensions.get_extension_for_class(x509.BasicConstraints) except x509.ExtensionNotFound: # pragma: no cover - extension should always be present return None return ext.value.path_length @property def max_pathlen(self) -> Optional[int]: """The maximum `pathlen` for any intermediate CAs signed by this CA. This value is either ``None``, if this and all parent CAs don't have a ``pathlen`` attribute, or an ``int`` if any parent CA has the attribute. """ if self.parent is None: return self.pathlen max_parent = self.parent.max_pathlen if max_parent is None: return self.pathlen if self.pathlen is None: return max_parent - 1 return min(self.pathlen, max_parent - 1) @property def allows_intermediate_ca(self) -> bool: """Whether this CA allows creating intermediate CAs.""" max_pathlen = self.max_pathlen return max_pathlen is None or max_pathlen > 0 @property def bundle(self) -> List["CertificateAuthority"]: """A list of any parent CAs, including this CA. The list is ordered so the Root CA will be the first. """ ca = self bundle = [ca] while ca.parent is not None: bundle.append(ca.parent) ca = ca.parent return bundle @property def root(self) -> "CertificateAuthority": """Get the root CA for this CA.""" if self.parent is None: return self ca = self while ca.parent is not None: ca = ca.parent return ca @property def usable(self) -> bool: """True if the CA is currently usable or not.""" return self.enabled and self.valid_from < timezone.now() < self.expires @property def is_openssh_ca(self) -> bool: """True if this CA is an OpenSSH CA.""" if SshHostCaExtension() in self.extensions: return True # COVERAGE NOTE: currently both extensions are always present return SshUserCaExtension() in self.extensions # pragma: no cover class Meta: verbose_name = _("Certificate Authority") verbose_name_plural = _("Certificate Authorities") def __str__(self) -> str: return self.name
[docs]class Certificate(X509CertMixin): """Model representing a x509 Certificate.""" objects: CertificateManager = CertificateManager.from_queryset(CertificateQuerySet)() watchers = models.ManyToManyField(Watcher, related_name="certificates", blank=True) ca = models.ForeignKey( CertificateAuthority, on_delete=models.CASCADE, verbose_name=_("Certificate Authority") ) csr = CertificateSigningRequestField(verbose_name=_("CSR"), blank=True, null=True) # Note: We don't set choices here because the available profiles might be changed by the user. profile = models.CharField( blank=True, default="", max_length=32, help_text=_("Profile that was used to generate this certificate."), ) autogenerated = models.BooleanField( default=False, help_text=_("If this certificate was automatically generated.") ) @property def bundle(self) -> List[X509CertMixin]: """The complete certificate bundle. This includes all CAs as well as the certificates itself.""" return [cast(X509CertMixin, self)] + cast(List[X509CertMixin], self.ca.bundle) @property def root(self) -> CertificateAuthority: """Get the root CA for this certificate.""" return self.ca.root def __str__(self) -> str: return self.cn
[docs]class AcmeAccount(DjangoCAModel): """Implements an ACME account object. .. seealso:: `RFC 8555, 7.1.2 <https://tools.ietf.org/html/rfc8555#section-7.1.2>`_ """ # RFC 8555, 7.1.2: "Possible values are "valid", "deactivated", and "revoked"." STATUS_VALID = Status.VALID.value STATUS_DEACTIVATED = Status.DEACTIVATED.value # deactivated by user STATUS_REVOKED = Status.REVOKED.value # revoked by server STATUS_CHOICES = ( (STATUS_VALID, _("Valid")), (STATUS_DEACTIVATED, _("Deactivated")), (STATUS_REVOKED, _("Revoked")), ) objects: AcmeAccountManager = AcmeAccountManager.from_queryset(AcmeAccountQuerySet)() # Account meta data created = models.DateTimeField(default=timezone.now) updated = models.DateTimeField(auto_now=True) # Account information ca = models.ForeignKey( CertificateAuthority, on_delete=models.CASCADE, verbose_name=_("Certificate Authority") ) # Full public key of the account pem = models.TextField(verbose_name=_("Public key"), unique=True, blank=False, validators=[pem_validator]) # JSON Web Key thumbprint - a hash of the public key, see RFC 7638. # NOTE: Only unique for the given CA to make hash collisions less likely thumbprint = models.CharField(max_length=64) slug = models.SlugField(unique=True, default=acme_slug) kid = models.URLField( unique=True, validators=[URLValidator(schemes=("http", "https"))], verbose_name=_("Key ID") ) # Fields according to RFC 8555, 7.1.2 # RFC 8555, 7.1.6: "Account objects are created in the "valid" state" status = models.CharField(choices=STATUS_CHOICES, max_length=12, default=STATUS_VALID) contact = models.TextField(blank=True, help_text=_("Contact addresses for this account, one per line.")) terms_of_service_agreed = models.BooleanField(default=False) # NOTE: externalAccountBinding is not yet supported # NOTE: orders property is provided by reverse relation of the AcmeOrder model class Meta: verbose_name = _("ACME Account") verbose_name_plural = _("ACME Accounts") unique_together = (("ca", "thumbprint"),) def __str__(self) -> str: try: return self.contact.split("\n", maxsplit=1)[0].split(":", 1)[1] except IndexError: return "" @property def serial(self) -> str: """Serial of the CA for this account.""" return self.ca.serial
[docs] def set_kid(self, request: HttpRequest) -> None: """Set the ACME kid based on this accounts CA and slug. Note that `slug` and `ca` must be already set when using this method. """ self.kid = request.build_absolute_uri( reverse("django_ca:acme-account", kwargs={"slug": self.slug, "serial": self.ca.serial}) )
@property def usable(self) -> bool: """Boolean if the account is currently usable. An account is usable if the terms of service have been agreed, the status is "valid" and the associated CA is usable. """ return self.terms_of_service_agreed and self.status == AcmeAccount.STATUS_VALID and self.ca.usable
[docs]class AcmeOrder(DjangoCAModel): """Implements an ACME order object. .. seealso:: `RFC 8555, 7.1.3 <https://tools.ietf.org/html/rfc8555#section-7.1.3>`_ """ # RFC 8555, 7.1.3: "Possible values are "pending", "ready", "processing", "valid", and "invalid"." STATUS_PENDING = Status.PENDING.value STATUS_READY = Status.READY.value STATUS_PROCESSING = Status.PROCESSING.value STATUS_VALID = Status.VALID.value STATUS_INVALID = Status.INVALID.value STATUS_CHOICES = ( (STATUS_INVALID, _("Invalid")), (STATUS_PENDING, _("Pending")), (STATUS_PROCESSING, _("Processing")), (STATUS_READY, _("Ready")), (STATUS_VALID, _("Valid")), ) objects = AcmeOrderManager.from_queryset(AcmeOrderQuerySet)() account = models.ForeignKey(AcmeAccount, on_delete=models.CASCADE, related_name="orders") slug = models.SlugField(unique=True, default=acme_slug) # Fields according to RFC 8555, 7.1.3 # RFC 8555, 7.1.6: "Order objects are created in the "pending" state." status = models.CharField(choices=STATUS_CHOICES, max_length=10, default=STATUS_PENDING) expires = models.DateTimeField(default=acme_order_expires) # NOTE: identifiers property is provided by reverse relation of the AcmeAuthorization model not_before = models.DateTimeField(null=True) not_after = models.DateTimeField(null=True) # NOTE: error property is not yet supported # NOTE: authorizations property is provided by reverse relation of the AcmeAuthorization model # NOTE: finalize property is provided by acme_finalize_url property # NOTE: certificate property is provided by reverse relation of the AcmeCertificate model class Meta: verbose_name = _("ACME Order") verbose_name_plural = _("ACME Orders") def __str__(self) -> str: return f"{self.slug} ({self.account})" @property def acme_url(self) -> str: """Get the ACME URL path for this order.""" return reverse("django_ca:acme-order", kwargs={"slug": self.slug, "serial": self.serial}) @property def acme_finalize_url(self) -> str: """Get the ACME "finalize" URL path for this order.""" return reverse("django_ca:acme-order-finalize", kwargs={"slug": self.slug, "serial": self.serial})
[docs] def add_authorizations(self, identifiers: Iterable["messages.Identifier"]) -> List["AcmeAuthorization"]: """Add :py:class:`~django_ca.models.AcmeAuthorization` instances for the given identifiers. Note that this method already adds the account authorization to the database. It does not verify if it already exists and will raise an IntegrityError if it does. Example:: >>> from acme import messages >>> identifier = messages.Identifier(typ=messages.IDENTIFIER_FQDN, value='example.com') >>> order.add_authorizations([identifier]) Parameters ---------- identifiers : list of :py:class:`acme:acme.messages.Identifier` The identifiers for this for this order. Returns ------- list of :py:class:`~django_ca.models.AcmeAuthorization` """ return self.authorizations.bulk_create( [AcmeAuthorization(type=ident.typ.name, value=ident.value, order=self) for ident in identifiers] )
@property def serial(self) -> str: """Serial of the CA for this order.""" return self.account.serial @property def usable(self) -> bool: """Boolean defining if an order is "usable", meaning it can be used to issue a certificate. An order is usable if it is in the "pending" status, has not expired and the account is usable. """ return ( self.status == AcmeOrder.STATUS_PENDING and self.expires > timezone.now() and self.account.usable )
[docs]class AcmeAuthorization(DjangoCAModel): """Implements an ACME authorization object. .. seealso:: `RFC 8555, 7.1.4 <https://tools.ietf.org/html/rfc8555#section-7.1.4>`_ """ # Choices from RFC 8555, section 9.7.7. # TODO: acme.messages defines an "ip" identifier, present in acme >= 1.19.0 TYPE_DNS = IdentifierType.DNS.value TYPE_CHOICES = ((TYPE_DNS, _("DNS")),) # RFC 8555, 7.1.4: "Possible values are "pending", "valid", "invalid", "deactivated", "expired", and # "revoked"." STATUS_PENDING = Status.PENDING.value STATUS_VALID = Status.VALID.value STATUS_INVALID = Status.INVALID.value STATUS_DEACTIVATED = Status.DEACTIVATED.value STATUS_EXPIRED = Status.EXPIRED.value STATUS_REVOKED = Status.REVOKED.value STATUS_CHOICES = ( (STATUS_PENDING, _("Pending")), (STATUS_VALID, _("Valid")), (STATUS_INVALID, _("Invalid")), (STATUS_DEACTIVATED, _("Deactivated")), (STATUS_EXPIRED, _("Expired")), (STATUS_REVOKED, _("Revoked")), ) objects = AcmeAuthorizationManager.from_queryset(AcmeAuthorizationQuerySet)() order = models.ForeignKey(AcmeOrder, on_delete=models.CASCADE, related_name="authorizations") slug = models.SlugField(unique=True, default=acme_slug) # Fields according to RFC 8555, 7.1.4: # NOTE: RFC 8555 does not specify a default value but DNS is the only known value type = models.CharField(choices=TYPE_CHOICES, max_length=8, default=TYPE_DNS) # identifier value = models.CharField(max_length=255) # identifier # RFC 8555, 7.1.6: "Authorization objects are created in the "pending" state." status = models.CharField(choices=STATUS_CHOICES, max_length=12, default=STATUS_PENDING) # NOTE: expires property comes from the linked order # NOTE: challenges property is provided by reverse relation of the AcmeChallenge model wildcard = models.BooleanField(default=False) class Meta: unique_together = (("order", "type", "value"),) verbose_name = _("ACME Authorization") verbose_name_plural = _("ACME Authorizations") def __str__(self) -> str: return f"{self.type}: {self.value}" @property def account(self) -> AcmeAccount: """Account that this authorization belongs to.""" return self.order.account @property def acme_url(self) -> str: """Get the ACME URL path for this account authorization.""" return reverse("django_ca:acme-authz", kwargs={"slug": self.slug, "serial": self.serial}) @property def expires(self) -> datetime: """When this authorization expires.""" return self.order.expires # so far there is no reason to have a different value here @property def identifier(self) -> "messages.Identifier": """Get ACME identifier for this object. Returns ------- identifier : :py:class:`acme:acme.messages.Identifier` """ if self.type == AcmeAuthorization.TYPE_DNS: return messages.Identifier(typ=messages.IDENTIFIER_FQDN, value=self.value) raise ValueError(f"Unknown identifier type: {self.type}") @property def serial(self) -> str: """Serial of the CA for this authorization.""" return self.order.serial @property def subject_alternative_name(self) -> str: """Get the domain for this challenge as prefixed SubjectAlternativeName. This method is intended to be used when creating the :py:class:`~django_ca.extensions.SubjectAlternativeName` extension for a certificate to be signed. """ return f"{self.type}:{self.value}"
[docs] def get_challenges(self) -> List["AcmeChallenge"]: """Get list of :py:class:`~django_ca.models.AcmeChallenge` objects for this authorization. Note that challenges will be created if they don't exist. """ return [ AcmeChallenge.objects.get_or_create(auth=self, type=AcmeChallenge.TYPE_HTTP_01)[0], # AcmeChallenge.objects.get_or_create(auth=self, type=AcmeChallenge.TYPE_TLS_ALPN_01)[0], AcmeChallenge.objects.get_or_create(auth=self, type=AcmeChallenge.TYPE_DNS_01)[0], ]
@property def usable(self) -> bool: """Boolean defining if an authentication can still can be used in order validation. An order is usable if it is in the "pending" or "invalid" status, the order is usable. An authorization that is in the "invalid" status is eligible to be retried by the client. """ states = (AcmeAuthorization.STATUS_PENDING, AcmeAuthorization.STATUS_INVALID) return self.status in states and self.order.usable
[docs]class AcmeChallenge(DjangoCAModel): """Implements an ACME Challenge Object. .. seealso:: `RFC 8555, section 7.1.5 <https://tools.ietf.org/html/rfc8555#section-7.1.5>`_ """ # Possible challenges TYPE_HTTP_01 = "http-01" TYPE_DNS_01 = "dns-01" TYPE_TLS_ALPN_01 = "tls-alpn-01" TYPE_CHOICES = ( (TYPE_HTTP_01, _("HTTP Challenge")), (TYPE_DNS_01, _("DNS Challenge")), (TYPE_TLS_ALPN_01, _("TLS ALPN Challenge")), ) # RFC 8555, 8: "Possible values are "pending", "processing", "valid", and "invalid"." STATUS_PENDING = Status.PENDING.value STATUS_PROCESSING = Status.PROCESSING.value STATUS_VALID = Status.VALID.value STATUS_INVALID = Status.INVALID.value STATUS_CHOICES = ( (STATUS_PENDING, _("Pending")), (STATUS_PROCESSING, _("Processing")), (STATUS_VALID, _("Valid")), (STATUS_INVALID, _("Name")), ) objects = AcmeChallengeManager.from_queryset(AcmeChallengeQuerySet)() auth = models.ForeignKey(AcmeAuthorization, on_delete=models.CASCADE, related_name="challenges") slug = models.SlugField(unique=True, default=acme_slug) # Fields according to RFC 8555, 8: type = models.CharField(choices=TYPE_CHOICES, max_length=12) # NOTE: url property is provided by the acme_url property and computed on the fly # RFC 8555, 7.1.6: "Challenge objects are created in the "pending" state." status = models.CharField(choices=STATUS_CHOICES, max_length=12, default=STATUS_PENDING) validated = models.DateTimeField(null=True, blank=True) error = models.CharField(blank=True, max_length=64) # max_length is just a guess # The token field is listed for both HTTP and DNS challenge, which are the most common types, so we # include it as an optional field here. It is generated when the token is first accessed. token = models.CharField(blank=True, max_length=64, default=acme_token) class Meta: unique_together = (("auth", "type"),) verbose_name = _("ACME Challenge") verbose_name_plural = _("ACME Challenges") def __str__(self) -> str: return f"{self.auth.value} ({self.type})" @property def account(self) -> AcmeAccount: """Account that this challenge belongs to.""" return self.auth.account @property def acme_url(self) -> str: """Get the ACME URL path for this challenge.""" return reverse("django_ca:acme-challenge", kwargs={"slug": self.slug, "serial": self.serial}) @property def acme_challenge(self) -> "challenges.KeyAuthorizationChallenge": """Challenge as ACME challenge object. Returns ------- :py:class:`acme:acme.challenges.Challenge` The acme representation of this class. """ token = self.token.encode() if self.type == AcmeChallenge.TYPE_HTTP_01: return challenges.HTTP01(token=token) if self.type == AcmeChallenge.TYPE_DNS_01: return challenges.DNS01(token=token) if self.type == AcmeChallenge.TYPE_TLS_ALPN_01: return challenges.TLSALPN01(token=token) raise ValueError(f"{self.type}: Unsupported challenge type.") @property def acme_validated(self) -> Optional[datetime]: """Timestamp when this challenge was validated. This property is a wrapper around the `validated` field. It always returns `None` if the challenge is not marked as valid (even if it had a timestamp), and the timestamp will always have a timezone, even if ``USE_TZ=False``. """ if self.status != AcmeChallenge.STATUS_VALID or self.validated is None: return None if timezone.is_naive(self.validated): return timezone.make_aware(self.validated, timezone=tz.utc) return self.validated @property def encoded_token(self) -> bytes: """Token in base64url encoded form.""" return jose.b64.b64encode(self.token.encode("ascii")) @property def expected(self) -> bytes: """Expected value for the challenge based on its type.""" thumbprint = self.account.thumbprint.encode("ascii") value = self.encoded_token + b"." + thumbprint if self.type == AcmeChallenge.TYPE_HTTP_01: return value if self.type == AcmeChallenge.TYPE_DNS_01: return jose.b64.b64encode(hashlib.sha256(value).digest()) raise ValueError(f"{self.type}: Unsupported challenge type.")
[docs] def get_challenge(self, request: HttpRequest) -> "messages.ChallengeBody": """Get the ACME challenge body for this challenge. Returns ------- :py:class:`acme:acme.messages.ChallengeBody` The acme representation of this class. """ url = request.build_absolute_uri(self.acme_url) # NOTE: RFC855, section 7.5 shows challenges *without* a status, but this object always includes it. # It does not seem to hurt, but might be a slight spec-violation. return messages.ChallengeBody( chall=self.acme_challenge, _url=url, status=self.status, validated=self.acme_validated )
@property def serial(self) -> str: """Serial of the CA for this challenge.""" return self.auth.serial @property def usable(self) -> bool: """Boolean defining if an challenge is "usable", meaning it still can be used in order validation. A challenge is usable if it is in the "pending" or "invalid status and the authorization is usable. """ states = (AcmeChallenge.STATUS_PENDING, AcmeChallenge.STATUS_INVALID) return self.status in states and self.auth.usable
[docs]class AcmeCertificate(DjangoCAModel): """Intermediate model for certificates to be issued via ACME.""" objects = AcmeCertificateManager.from_queryset(AcmeCertificateQuerySet)() slug = models.SlugField(unique=True, default=acme_slug) order = models.OneToOneField(AcmeOrder, on_delete=models.CASCADE) cert = models.OneToOneField(Certificate, on_delete=models.CASCADE, null=True) csr = models.TextField(verbose_name=_("CSR")) class Meta: verbose_name = _("ACME Certificate") verbose_name_plural = _("ACME Certificate") @property def acme_url(self) -> str: """Get the ACME URL path for this certificate.""" return reverse("django_ca:acme-cert", kwargs={"slug": self.slug, "serial": self.order.serial})
[docs] def parse_csr(self) -> x509.CertificateSigningRequest: """Load the CSR into a cryptography object. Returns ------- :py:class:`~cg:cryptography.x509.CertificateSigningRequest` The CSR as used by cryptography. """ return x509.load_pem_x509_csr(self.csr.encode())
@property def usable(self) -> bool: """Boolean defining if this instance is "usable", meaning we can use it to issue a certificate. An ACME certificate is considered usable if no actual certificate has yet been issued, the order is not expired and in the "processing" state. """ return ( self.cert is None and self.order.expires > timezone.now() and self.order.status == AcmeOrder.STATUS_PROCESSING )