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# coding: utf-8
"""
ASN.1 type classes for cryptographic message syntax (CMS). Structures are also
compatible with PKCS#7. Exports the following items:
- AuthenticatedData()
- AuthEnvelopedData()
- CompressedData()
- ContentInfo()
- DigestedData()
- EncryptedData()
- EnvelopedData()
- SignedAndEnvelopedData()
- SignedData()
Other type classes are defined that help compose the types listed above.
"""
from __future__ import unicode_literals, division, absolute_import, print_function
try:
import zlib
except (ImportError):
zlib = None
from .algos import (
_ForceNullParameters,
DigestAlgorithm,
EncryptionAlgorithm,
HmacAlgorithm,
KdfAlgorithm,
SignedDigestAlgorithm,
)
from .core import (
Any,
BitString,
Choice,
Enumerated,
GeneralizedTime,
Integer,
ObjectIdentifier,
OctetBitString,
OctetString,
ParsableOctetString,
Sequence,
SequenceOf,
SetOf,
UTCTime,
UTF8String,
)
from .crl import CertificateList
from .keys import PublicKeyInfo
from .ocsp import OCSPResponse
from .x509 import Attributes, Certificate, Extensions, GeneralName, GeneralNames, Name
# These structures are taken from
# ftp://ftp.rsasecurity.com/pub/pkcs/ascii/pkcs-6.asc
class ExtendedCertificateInfo(Sequence):
_fields = [
('version', Integer),
('certificate', Certificate),
('attributes', Attributes),
]
class ExtendedCertificate(Sequence):
_fields = [
('extended_certificate_info', ExtendedCertificateInfo),
('signature_algorithm', SignedDigestAlgorithm),
('signature', OctetBitString),
]
# These structures are taken from https://tools.ietf.org/html/rfc5652,
# https://tools.ietf.org/html/rfc5083, http://tools.ietf.org/html/rfc2315,
# https://tools.ietf.org/html/rfc5940, https://tools.ietf.org/html/rfc3274,
# https://tools.ietf.org/html/rfc3281
class CMSVersion(Integer):
_map = {
0: 'v0',
1: 'v1',
2: 'v2',
3: 'v3',
4: 'v4',
5: 'v5',
}
class CMSAttributeType(ObjectIdentifier):
_map = {
'1.2.840.113549.1.9.3': 'content_type',
'1.2.840.113549.1.9.4': 'message_digest',
'1.2.840.113549.1.9.5': 'signing_time',
'1.2.840.113549.1.9.6': 'counter_signature',
# https://tools.ietf.org/html/rfc3161#page-20
'1.2.840.113549.1.9.16.2.14': 'signature_time_stamp_token',
}
class Time(Choice):
_alternatives = [
('utc_time', UTCTime),
('generalized_time', GeneralizedTime),
]
class ContentType(ObjectIdentifier):
_map = {
'1.2.840.113549.1.7.1': 'data',
'1.2.840.113549.1.7.2': 'signed_data',
'1.2.840.113549.1.7.3': 'enveloped_data',
'1.2.840.113549.1.7.4': 'signed_and_enveloped_data',
'1.2.840.113549.1.7.5': 'digested_data',
'1.2.840.113549.1.7.6': 'encrypted_data',
'1.2.840.113549.1.9.16.1.2': 'authenticated_data',
'1.2.840.113549.1.9.16.1.9': 'compressed_data',
'1.2.840.113549.1.9.16.1.23': 'authenticated_enveloped_data',
}
class SetOfContentType(SetOf):
_child_spec = ContentType
class SetOfOctetString(SetOf):
_child_spec = OctetString
class SetOfTime(SetOf):
_child_spec = Time
class SetOfAny(SetOf):
_child_spec = Any
class CMSAttribute(Sequence):
_fields = [
('type', CMSAttributeType),
('values', None),
]
_oid_specs = {}
def _values_spec(self):
return self._oid_specs.get(self['type'].native, SetOfAny)
_spec_callbacks = {
'values': _values_spec
}
class CMSAttributes(SetOf):
_child_spec = CMSAttribute
class IssuerSerial(Sequence):
_fields = [
('issuer', GeneralNames),
('serial', Integer),
('issuer_uid', OctetBitString, {'optional': True}),
]
class AttCertVersion(Integer):
_map = {
0: 'v1',
1: 'v2',
}
class AttCertSubject(Choice):
_alternatives = [
('base_certificate_id', IssuerSerial, {'tag_type': 'explicit', 'tag': 0}),
('subject_name', GeneralNames, {'tag_type': 'explicit', 'tag': 1}),
]
class AttCertValidityPeriod(Sequence):
_fields = [
('not_before_time', GeneralizedTime),
('not_after_time', GeneralizedTime),
]
class AttributeCertificateInfoV1(Sequence):
_fields = [
('version', AttCertVersion, {'default': 'v1'}),
('subject', AttCertSubject),
('issuer', GeneralNames),
('signature', SignedDigestAlgorithm),
('serial_number', Integer),
('att_cert_validity_period', AttCertValidityPeriod),
('attributes', Attributes),
('issuer_unique_id', OctetBitString, {'optional': True}),
('extensions', Extensions, {'optional': True}),
]
class AttributeCertificateV1(Sequence):
_fields = [
('ac_info', AttributeCertificateInfoV1),
('signature_algorithm', SignedDigestAlgorithm),
('signature', OctetBitString),
]
class DigestedObjectType(Enumerated):
_map = {
0: 'public_key',
1: 'public_key_cert',
2: 'other_objy_types',
}
class ObjectDigestInfo(Sequence):
_fields = [
('digested_object_type', DigestedObjectType),
('other_object_type_id', ObjectIdentifier, {'optional': True}),
('digest_algorithm', DigestAlgorithm),
('object_digest', OctetBitString),
]
class Holder(Sequence):
_fields = [
('base_certificate_id', IssuerSerial, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('entity_name', GeneralNames, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
('object_digest_info', ObjectDigestInfo, {'tag_type': 'implicit', 'tag': 2, 'optional': True}),
]
class V2Form(Sequence):
_fields = [
('issuer_name', GeneralNames, {'optional': True}),
('base_certificate_id', IssuerSerial, {'tag_type': 'explicit', 'tag': 0, 'optional': True}),
('object_digest_info', ObjectDigestInfo, {'tag_type': 'explicit', 'tag': 1, 'optional': True}),
]
class AttCertIssuer(Choice):
_alternatives = [
('v1_form', GeneralNames),
('v2_form', V2Form, {'tag_type': 'explicit', 'tag': 0}),
]
class IetfAttrValue(Choice):
_alternatives = [
('octets', OctetString),
('oid', ObjectIdentifier),
('string', UTF8String),
]
class IetfAttrValues(SequenceOf):
_child_spec = IetfAttrValue
class IetfAttrSyntax(Sequence):
_fields = [
('policy_authority', GeneralNames, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('values', IetfAttrValues),
]
class SetOfIetfAttrSyntax(SetOf):
_child_spec = IetfAttrSyntax
class SvceAuthInfo(Sequence):
_fields = [
('service', GeneralName),
('ident', GeneralName),
('auth_info', OctetString, {'optional': True}),
]
class SetOfSvceAuthInfo(SetOf):
_child_spec = SvceAuthInfo
class RoleSyntax(Sequence):
_fields = [
('role_authority', GeneralNames, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('role_name', GeneralName, {'tag_type': 'implicit', 'tag': 1}),
]
class SetOfRoleSyntax(SetOf):
_child_spec = RoleSyntax
class ClassList(BitString):
_map = {
0: 'unmarked',
1: 'unclassified',
2: 'restricted',
3: 'confidential',
4: 'secret',
5: 'top_secret',
}
class SecurityCategory(Sequence):
_fields = [
('type', ObjectIdentifier, {'tag_type': 'implicit', 'tag': 0}),
('value', Any, {'tag_type': 'implicit', 'tag': 1}),
]
class SetOfSecurityCategory(SetOf):
_child_spec = SecurityCategory
class Clearance(Sequence):
_fields = [
('policy_id', ObjectIdentifier, {'tag_type': 'implicit', 'tag': 0}),
('class_list', ClassList, {'tag_type': 'implicit', 'tag': 1, 'default': 'unclassified'}),
('security_categories', SetOfSecurityCategory, {'tag_type': 'implicit', 'tag': 2, 'optional': True}),
]
class SetOfClearance(SetOf):
_child_spec = Clearance
class BigTime(Sequence):
_fields = [
('major', Integer),
('fractional_seconds', Integer),
('sign', Integer, {'optional': True}),
]
class LeapData(Sequence):
_fields = [
('leap_time', BigTime),
('action', Integer),
]
class SetOfLeapData(SetOf):
_child_spec = LeapData
class TimingMetrics(Sequence):
_fields = [
('ntp_time', BigTime),
('offset', BigTime),
('delay', BigTime),
('expiration', BigTime),
('leap_event', SetOfLeapData, {'optional': True}),
]
class SetOfTimingMetrics(SetOf):
_child_spec = TimingMetrics
class TimingPolicy(Sequence):
_fields = [
('policy_id', SequenceOf, {'spec': ObjectIdentifier}),
('max_offset', BigTime, {'tag_type': 'explicit', 'tag': 0, 'optional': True}),
('max_delay', BigTime, {'tag_type': 'explicit', 'tag': 1, 'optional': True}),
]
class SetOfTimingPolicy(SetOf):
_child_spec = TimingPolicy
class AttCertAttributeType(ObjectIdentifier):
_map = {
'1.3.6.1.5.5.7.10.1': 'authentication_info',
'1.3.6.1.5.5.7.10.2': 'access_identity',
'1.3.6.1.5.5.7.10.3': 'charging_identity',
'1.3.6.1.5.5.7.10.4': 'group',
'2.5.4.72': 'role',
'2.5.4.55': 'clearance',
'1.3.6.1.4.1.601.10.4.1': 'timing_metrics',
'1.3.6.1.4.1.601.10.4.2': 'timing_policy',
}
class AttCertAttribute(Sequence):
_fields = [
('type', AttCertAttributeType),
('values', None),
]
_oid_specs = {
'authentication_info': SetOfSvceAuthInfo,
'access_identity': SetOfSvceAuthInfo,
'charging_identity': SetOfIetfAttrSyntax,
'group': SetOfIetfAttrSyntax,
'role': SetOfRoleSyntax,
'clearance': SetOfClearance,
'timing_metrics': SetOfTimingMetrics,
'timing_policy': SetOfTimingPolicy,
}
def _values_spec(self):
return self._oid_specs.get(self['type'].native, SetOfAny)
_spec_callbacks = {
'values': _values_spec
}
class AttCertAttributes(SequenceOf):
_child_spec = AttCertAttribute
class AttributeCertificateInfoV2(Sequence):
_fields = [
('version', AttCertVersion),
('holder', Holder),
('issuer', AttCertIssuer),
('signature', SignedDigestAlgorithm),
('serial_number', Integer),
('att_cert_validity_period', AttCertValidityPeriod),
('attributes', AttCertAttributes),
('issuer_unique_id', OctetBitString, {'optional': True}),
('extensions', Extensions, {'optional': True}),
]
class AttributeCertificateV2(Sequence):
# Handle the situation where a V2 cert is encoded as V1
_bad_tag = 1
_fields = [
('ac_info', AttributeCertificateInfoV2),
('signature_algorithm', SignedDigestAlgorithm),
('signature', OctetBitString),
]
class OtherCertificateFormat(Sequence):
_fields = [
('other_cert_format', ObjectIdentifier),
('other_cert', Any),
]
class CertificateChoices(Choice):
_alternatives = [
('certificate', Certificate),
('extended_certificate', ExtendedCertificate, {'tag_type': 'implicit', 'tag': 0}),
('v1_attr_cert', AttributeCertificateV1, {'tag_type': 'implicit', 'tag': 1}),
('v2_attr_cert', AttributeCertificateV2, {'tag_type': 'implicit', 'tag': 2}),
('other', OtherCertificateFormat, {'tag_type': 'implicit', 'tag': 3}),
]
def validate(self, class_, tag, contents):
"""
Ensures that the class and tag specified exist as an alternative. This
custom version fixes parsing broken encodings there a V2 attribute
# certificate is encoded as a V1
:param class_:
The integer class_ from the encoded value header
:param tag:
The integer tag from the encoded value header
:param contents:
A byte string of the contents of the value - used when the object
is explicitly tagged
:raises:
ValueError - when value is not a valid alternative
"""
super(CertificateChoices, self).validate(class_, tag, contents)
if self._choice == 2:
if AttCertVersion.load(Sequence.load(contents)[0].dump()).native == 'v2':
self._choice = 3
class CertificateSet(SetOf):
_child_spec = CertificateChoices
class ContentInfo(Sequence):
_fields = [
('content_type', ContentType),
('content', Any, {'tag_type': 'explicit', 'tag': 0, 'optional': True}),
]
_oid_pair = ('content_type', 'content')
_oid_specs = {}
class SetOfContentInfo(SetOf):
_child_spec = ContentInfo
class EncapsulatedContentInfo(Sequence):
_fields = [
('content_type', ContentType),
('content', ParsableOctetString, {'tag_type': 'explicit', 'tag': 0, 'optional': True}),
]
_oid_pair = ('content_type', 'content')
_oid_specs = {}
class IssuerAndSerialNumber(Sequence):
_fields = [
('issuer', Name),
('serial_number', Integer),
]
class SignerIdentifier(Choice):
_alternatives = [
('issuer_and_serial_number', IssuerAndSerialNumber),
('subject_key_identifier', OctetString, {'tag_type': 'implicit', 'tag': 0}),
]
class DigestAlgorithms(SetOf):
_child_spec = DigestAlgorithm
class CertificateRevocationLists(SetOf):
_child_spec = CertificateList
class SCVPReqRes(Sequence):
_fields = [
('request', ContentInfo, {'tag_type': 'explicit', 'tag': 0, 'optional': True}),
('response', ContentInfo),
]
class OtherRevInfoFormatId(ObjectIdentifier):
_map = {
'1.3.6.1.5.5.7.16.2': 'ocsp_response',
'1.3.6.1.5.5.7.16.4': 'scvp',
}
class OtherRevocationInfoFormat(Sequence):
_fields = [
('other_rev_info_format', OtherRevInfoFormatId),
('other_rev_info', Any),
]
_oid_pair = ('other_rev_info_format', 'other_rev_info')
_oid_specs = {
'ocsp_response': OCSPResponse,
'scvp': SCVPReqRes,
}
class RevocationInfoChoice(Choice):
_alternatives = [
('crl', CertificateList),
('other', OtherRevocationInfoFormat, {'tag_type': 'implciit', 'tag': 1}),
]
class RevocationInfoChoices(SetOf):
_child_spec = RevocationInfoChoice
class SignerInfo(Sequence):
_fields = [
('version', CMSVersion),
('sid', SignerIdentifier),
('digest_algorithm', DigestAlgorithm),
('signed_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('signature_algorithm', SignedDigestAlgorithm),
('signature', OctetString),
('unsigned_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
]
class SignerInfos(SetOf):
_child_spec = SignerInfo
class SignedData(Sequence):
_fields = [
('version', CMSVersion),
('digest_algorithms', DigestAlgorithms),
('encap_content_info', None),
('certificates', CertificateSet, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('crls', RevocationInfoChoices, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
('signer_infos', SignerInfos),
]
def _encap_content_info_spec(self):
# If the encap_content_info is version v1, then this could be a PKCS#7
# structure, or a CMS structure. CMS wraps the encoded value in an
# Octet String tag.
# If the version is greater than 1, it is definite CMS
if self['version'].native != 'v1':
return EncapsulatedContentInfo
# Otherwise, the ContentInfo spec from PKCS#7 will be compatible with
# CMS v1 (which only allows Data, an Octet String) and PKCS#7, which
# allows Any
return ContentInfo
_spec_callbacks = {
'encap_content_info': _encap_content_info_spec
}
class OriginatorInfo(Sequence):
_fields = [
('certs', CertificateSet, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('crls', RevocationInfoChoices, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
]
class RecipientIdentifier(Choice):
_alternatives = [
('issuer_and_serial_number', IssuerAndSerialNumber),
('subject_key_identifier', OctetString, {'tag_type': 'implicit', 'tag': 0}),
]
class KeyEncryptionAlgorithmId(ObjectIdentifier):
_map = {
'1.2.840.113549.1.1.1': 'rsa',
'2.16.840.1.101.3.4.1.5': 'aes128_wrap',
'2.16.840.1.101.3.4.1.8': 'aes128_wrap_pad',
'2.16.840.1.101.3.4.1.25': 'aes192_wrap',
'2.16.840.1.101.3.4.1.28': 'aes192_wrap_pad',
'2.16.840.1.101.3.4.1.45': 'aes256_wrap',
'2.16.840.1.101.3.4.1.48': 'aes256_wrap_pad',
}
class KeyEncryptionAlgorithm(_ForceNullParameters, Sequence):
_fields = [
('algorithm', KeyEncryptionAlgorithmId),
('parameters', Any, {'optional': True}),
]
class KeyTransRecipientInfo(Sequence):
_fields = [
('version', CMSVersion),
('rid', RecipientIdentifier),
('key_encryption_algorithm', KeyEncryptionAlgorithm),
('encrypted_key', OctetString),
]
class OriginatorIdentifierOrKey(Choice):
_alternatives = [
('issuer_and_serial_number', IssuerAndSerialNumber),
('subject_key_identifier', OctetString, {'tag_type': 'implicit', 'tag': 0}),
('originator_key', PublicKeyInfo, {'tag_type': 'implicit', 'tag': 1}),
]
class OtherKeyAttribute(Sequence):
_fields = [
('key_attr_id', ObjectIdentifier),
('key_attr', Any),
]
class RecipientKeyIdentifier(Sequence):
_fields = [
('subject_key_identifier', OctetString),
('date', GeneralizedTime, {'optional': True}),
('other', OtherKeyAttribute, {'optional': True}),
]
class KeyAgreementRecipientIdentifier(Choice):
_alternatives = [
('issuer_and_serial_number', IssuerAndSerialNumber),
('r_key_id', RecipientKeyIdentifier, {'tag_type': 'implicit', 'tag': 0}),
]
class RecipientEncryptedKey(Sequence):
_fields = [
('rid', KeyAgreementRecipientIdentifier),
('encrypted_key', OctetString),
]
class RecipientEncryptedKeys(SequenceOf):
_child_spec = RecipientEncryptedKey
class KeyAgreeRecipientInfo(Sequence):
_fields = [
('version', CMSVersion),
('originator', OriginatorIdentifierOrKey, {'tag_type': 'explicit', 'tag': 0}),
('ukm', OctetString, {'tag_type': 'explicit', 'tag': 1, 'optional': True}),
('key_encryption_algorithm', KeyEncryptionAlgorithm),
('recipient_encrypted_keys', RecipientEncryptedKeys),
]
class KEKIdentifier(Sequence):
_fields = [
('key_identifier', OctetString),
('date', GeneralizedTime, {'optional': True}),
('other', OtherKeyAttribute, {'optional': True}),
]
class KEKRecipientInfo(Sequence):
_fields = [
('version', CMSVersion),
('kekid', KEKIdentifier),
('key_encryption_algorithm', KeyEncryptionAlgorithm),
('encrypted_key', OctetString),
]
class PasswordRecipientInfo(Sequence):
_fields = [
('version', CMSVersion),
('key_derivation_algorithm', KdfAlgorithm, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('key_encryption_algorithm', KeyEncryptionAlgorithm),
('encrypted_key', OctetString),
]
class OtherRecipientInfo(Sequence):
_fields = [
('ori_type', ObjectIdentifier),
('ori_value', Any),
]
class RecipientInfo(Choice):
_alternatives = [
('ktri', KeyTransRecipientInfo),
('kari', KeyAgreeRecipientInfo, {'tag_type': 'implicit', 'tag': 1}),
('kekri', KEKRecipientInfo, {'tag_type': 'implicit', 'tag': 2}),
('pwri', PasswordRecipientInfo, {'tag_type': 'implicit', 'tag': 3}),
('ori', OtherRecipientInfo, {'tag_type': 'implicit', 'tag': 4}),
]
class RecipientInfos(SetOf):
_child_spec = RecipientInfo
class EncryptedContentInfo(Sequence):
_fields = [
('content_type', ContentType),
('content_encryption_algorithm', EncryptionAlgorithm),
('encrypted_content', OctetString, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
]
class EnvelopedData(Sequence):
_fields = [
('version', CMSVersion),
('originator_info', OriginatorInfo, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('recipient_infos', RecipientInfos),
('encrypted_content_info', EncryptedContentInfo),
('unprotected_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
]
class SignedAndEnvelopedData(Sequence):
_fields = [
('version', CMSVersion),
('recipient_infos', RecipientInfos),
('digest_algorithms', DigestAlgorithms),
('encrypted_content_info', EncryptedContentInfo),
('certificates', CertificateSet, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('crls', CertificateRevocationLists, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
('signer_infos', SignerInfos),
]
class DigestedData(Sequence):
_fields = [
('version', CMSVersion),
('digest_algorithm', DigestAlgorithm),
('encap_content_info', None),
('digest', OctetString),
]
def _encap_content_info_spec(self):
# If the encap_content_info is version v1, then this could be a PKCS#7
# structure, or a CMS structure. CMS wraps the encoded value in an
# Octet String tag.
# If the version is greater than 1, it is definite CMS
if self['version'].native != 'v1':
return EncapsulatedContentInfo
# Otherwise, the ContentInfo spec from PKCS#7 will be compatible with
# CMS v1 (which only allows Data, an Octet String) and PKCS#7, which
# allows Any
return ContentInfo
_spec_callbacks = {
'encap_content_info': _encap_content_info_spec
}
class EncryptedData(Sequence):
_fields = [
('version', CMSVersion),
('encrypted_content_info', EncryptedContentInfo),
('unprotected_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
]
class AuthenticatedData(Sequence):
_fields = [
('version', CMSVersion),
('originator_info', OriginatorInfo, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('recipient_infos', RecipientInfos),
('mac_algorithm', HmacAlgorithm),
('digest_algorithm', DigestAlgorithm, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
# This does not require the _spec_callbacks approach of SignedData and
# DigestedData since AuthenticatedData was not part of PKCS#7
('encap_content_info', EncapsulatedContentInfo),
('auth_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 2, 'optional': True}),
('mac', OctetString),
('unauth_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 3, 'optional': True}),
]
class AuthEnvelopedData(Sequence):
_fields = [
('version', CMSVersion),
('originator_info', OriginatorInfo, {'tag_type': 'implicit', 'tag': 0, 'optional': True}),
('recipient_infos', RecipientInfos),
('auth_encrypted_content_info', EncryptedContentInfo),
('auth_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 1, 'optional': True}),
('mac', OctetString),
('unauth_attrs', CMSAttributes, {'tag_type': 'implicit', 'tag': 2, 'optional': True}),
]
class CompressionAlgorithmId(ObjectIdentifier):
_map = {
'1.2.840.113549.1.9.16.3.8': 'zlib',
}
class CompressionAlgorithm(Sequence):
_fields = [
('algorithm', CompressionAlgorithmId),
('parameters', Any, {'optional': True}),
]
class CompressedData(Sequence):
_fields = [
('version', CMSVersion),
('compression_algorithm', CompressionAlgorithm),
('encap_content_info', EncapsulatedContentInfo),
]
_decompressed = None
@property
def decompressed(self):
if self._decompressed is None:
if zlib is None:
raise SystemError('The zlib module is not available')
self._decompressed = zlib.decompress(self['encap_content_info']['content'].native)
return self._decompressed
ContentInfo._oid_specs = {
'data': OctetString,
'signed_data': SignedData,
'enveloped_data': EnvelopedData,
'signed_and_enveloped_data': SignedAndEnvelopedData,
'digested_data': DigestedData,
'encrypted_data': EncryptedData,
'authenticated_data': AuthenticatedData,
'compressed_data': CompressedData,
'authenticated_enveloped_data': AuthEnvelopedData,
}
EncapsulatedContentInfo._oid_specs = {
'signed_data': SignedData,
'enveloped_data': EnvelopedData,
'signed_and_enveloped_data': SignedAndEnvelopedData,
'digested_data': DigestedData,
'encrypted_data': EncryptedData,
'authenticated_data': AuthenticatedData,
'compressed_data': CompressedData,
'authenticated_enveloped_data': AuthEnvelopedData,
}
CMSAttribute._oid_specs = {
'content_type': SetOfContentType,
'message_digest': SetOfOctetString,
'signing_time': SetOfTime,
'counter_signature': SignerInfos,
'signature_time_stamp_token': SetOfContentInfo,
}
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