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Diffstat (limited to 'pyasn1_modules/rfc5751.py')
-rw-r--r-- | pyasn1_modules/rfc5751.py | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/pyasn1_modules/rfc5751.py b/pyasn1_modules/rfc5751.py new file mode 100644 index 0000000..7e20001 --- /dev/null +++ b/pyasn1_modules/rfc5751.py @@ -0,0 +1,124 @@ +# This file is being contributed to pyasn1-modules software. +# +# Created by Russ Housley with assistance from asn1ate v.0.6.0. +# +# Copyright (c) 2019, Vigil Security, LLC +# License: http://snmplabs.com/pyasn1/license.html +# +# S/MIME Version 3.2 Message Specification +# +# ASN.1 source from: +# https://www.rfc-editor.org/rfc/rfc5751.txt + +from pyasn1.type import namedtype +from pyasn1.type import opentype +from pyasn1.type import tag +from pyasn1.type import univ + +from pyasn1_modules import rfc5652 +from pyasn1_modules import rfc8018 + + +def _OID(*components): + output = [] + for x in tuple(components): + if isinstance(x, univ.ObjectIdentifier): + output.extend(list(x)) + else: + output.append(int(x)) + return univ.ObjectIdentifier(output) + + +# Imports from RFC 5652 and RFC 8018 + +IssuerAndSerialNumber = rfc5652.IssuerAndSerialNumber + +RecipientKeyIdentifier = rfc5652.RecipientKeyIdentifier + +SubjectKeyIdentifier = rfc5652.SubjectKeyIdentifier + +rc2CBC = rfc8018.rc2CBC + + +# S/MIME Capabilities Attribute + +smimeCapabilities = univ.ObjectIdentifier('1.2.840.113549.1.9.15') + + +smimeCapabilityMap = { } + + +class SMIMECapability(univ.Sequence): + pass + +SMIMECapability.componentType = namedtype.NamedTypes( + namedtype.NamedType('capabilityID', univ.ObjectIdentifier()), + namedtype.OptionalNamedType('parameters', univ.Any(), + openType=opentype.OpenType('capabilityID', smimeCapabilityMap)) +) + + +class SMIMECapabilities(univ.SequenceOf): + pass + +SMIMECapabilities.componentType = SMIMECapability() + + +class SMIMECapabilitiesParametersForRC2CBC(univ.Integer): + # which carries the RC2 Key Length (number of bits) + pass + + +# S/MIME Encryption Key Preference Attribute + +id_smime = univ.ObjectIdentifier('1.2.840.113549.1.9.16') + +id_aa = _OID(id_smime, 2) + +id_aa_encrypKeyPref = _OID(id_aa, 11) + + +class SMIMEEncryptionKeyPreference(univ.Choice): + pass + +SMIMEEncryptionKeyPreference.componentType = namedtype.NamedTypes( + namedtype.NamedType('issuerAndSerialNumber', + IssuerAndSerialNumber().subtype(implicitTag=tag.Tag( + tag.tagClassContext, tag.tagFormatSimple, 0))), + namedtype.NamedType('receipentKeyId', + # Yes, 'receipentKeyId' is spelled incorrectly, but kept + # this way for alignment with the ASN.1 module in the RFC. + RecipientKeyIdentifier().subtype(implicitTag=tag.Tag( + tag.tagClassContext, tag.tagFormatSimple, 1))), + namedtype.NamedType('subjectAltKeyIdentifier', + SubjectKeyIdentifier().subtype(implicitTag=tag.Tag( + tag.tagClassContext, tag.tagFormatSimple, 2))) +) + + +# The Prefer Binary Inside SMIMECapabilities attribute + +id_cap = _OID(id_smime, 11) + +id_cap_preferBinaryInside = _OID(id_cap, 1) + + +# CMS Attribute Map + +_cmsAttributesMapUpdate = { + smimeCapabilities: SMIMECapabilities(), + id_aa_encrypKeyPref: SMIMEEncryptionKeyPreference(), +} + +rfc5652.cmsAttributesMap.update(_cmsAttributesMapUpdate) + + +# SMIMECapabilities Attribute Map +# +# Do not include OIDs in the dictionary when the parameters are absent. + +_smimeCapabilityMapUpdate = { + rc2CBC: SMIMECapabilitiesParametersForRC2CBC(), +} + +smimeCapabilityMap.update(_smimeCapabilityMapUpdate) |