%PDF-
%PDF-
Mini Shell
Mini Shell
#
# This file is part of pyasn1 software.
#
# Copyright (c) 2005-2019, Ilya Etingof <etingof@gmail.com>
# License: http://snmplabs.com/pyasn1/license.html
#
try:
from collections import OrderedDict
except ImportError:
OrderedDict = dict
from pyasn1 import debug
from pyasn1 import error
from pyasn1.type import base
from pyasn1.type import char
from pyasn1.type import tag
from pyasn1.type import univ
from pyasn1.type import useful
__all__ = ['encode']
LOG = debug.registerLoggee(__name__, flags=debug.DEBUG_ENCODER)
class AbstractItemEncoder(object):
def encode(self, value, encodeFun, **options):
raise error.PyAsn1Error('Not implemented')
class BooleanEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return bool(value)
class IntegerEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return int(value)
class BitStringEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return str(value)
class OctetStringEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return value.asOctets()
class TextStringEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return str(value)
class NullEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return None
class ObjectIdentifierEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return str(value)
class RealEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return float(value)
class SetEncoder(AbstractItemEncoder):
protoDict = dict
def encode(self, value, encodeFun, **options):
inconsistency = value.isInconsistent
if inconsistency:
raise inconsistency
namedTypes = value.componentType
substrate = self.protoDict()
for idx, (key, subValue) in enumerate(value.items()):
if namedTypes and namedTypes[idx].isOptional and not value[idx].isValue:
continue
substrate[key] = encodeFun(subValue, **options)
return substrate
class SequenceEncoder(SetEncoder):
protoDict = OrderedDict
class SequenceOfEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
inconsistency = value.isInconsistent
if inconsistency:
raise inconsistency
return [encodeFun(x, **options) for x in value]
class ChoiceEncoder(SequenceEncoder):
pass
class AnyEncoder(AbstractItemEncoder):
def encode(self, value, encodeFun, **options):
return value.asOctets()
tagMap = {
univ.Boolean.tagSet: BooleanEncoder(),
univ.Integer.tagSet: IntegerEncoder(),
univ.BitString.tagSet: BitStringEncoder(),
univ.OctetString.tagSet: OctetStringEncoder(),
univ.Null.tagSet: NullEncoder(),
univ.ObjectIdentifier.tagSet: ObjectIdentifierEncoder(),
univ.Enumerated.tagSet: IntegerEncoder(),
univ.Real.tagSet: RealEncoder(),
# Sequence & Set have same tags as SequenceOf & SetOf
univ.SequenceOf.tagSet: SequenceOfEncoder(),
univ.SetOf.tagSet: SequenceOfEncoder(),
univ.Choice.tagSet: ChoiceEncoder(),
# character string types
char.UTF8String.tagSet: TextStringEncoder(),
char.NumericString.tagSet: TextStringEncoder(),
char.PrintableString.tagSet: TextStringEncoder(),
char.TeletexString.tagSet: TextStringEncoder(),
char.VideotexString.tagSet: TextStringEncoder(),
char.IA5String.tagSet: TextStringEncoder(),
char.GraphicString.tagSet: TextStringEncoder(),
char.VisibleString.tagSet: TextStringEncoder(),
char.GeneralString.tagSet: TextStringEncoder(),
char.UniversalString.tagSet: TextStringEncoder(),
char.BMPString.tagSet: TextStringEncoder(),
# useful types
useful.ObjectDescriptor.tagSet: OctetStringEncoder(),
useful.GeneralizedTime.tagSet: OctetStringEncoder(),
useful.UTCTime.tagSet: OctetStringEncoder()
}
# Put in ambiguous & non-ambiguous types for faster codec lookup
typeMap = {
univ.Boolean.typeId: BooleanEncoder(),
univ.Integer.typeId: IntegerEncoder(),
univ.BitString.typeId: BitStringEncoder(),
univ.OctetString.typeId: OctetStringEncoder(),
univ.Null.typeId: NullEncoder(),
univ.ObjectIdentifier.typeId: ObjectIdentifierEncoder(),
univ.Enumerated.typeId: IntegerEncoder(),
univ.Real.typeId: RealEncoder(),
# Sequence & Set have same tags as SequenceOf & SetOf
univ.Set.typeId: SetEncoder(),
univ.SetOf.typeId: SequenceOfEncoder(),
univ.Sequence.typeId: SequenceEncoder(),
univ.SequenceOf.typeId: SequenceOfEncoder(),
univ.Choice.typeId: ChoiceEncoder(),
univ.Any.typeId: AnyEncoder(),
# character string types
char.UTF8String.typeId: OctetStringEncoder(),
char.NumericString.typeId: OctetStringEncoder(),
char.PrintableString.typeId: OctetStringEncoder(),
char.TeletexString.typeId: OctetStringEncoder(),
char.VideotexString.typeId: OctetStringEncoder(),
char.IA5String.typeId: OctetStringEncoder(),
char.GraphicString.typeId: OctetStringEncoder(),
char.VisibleString.typeId: OctetStringEncoder(),
char.GeneralString.typeId: OctetStringEncoder(),
char.UniversalString.typeId: OctetStringEncoder(),
char.BMPString.typeId: OctetStringEncoder(),
# useful types
useful.ObjectDescriptor.typeId: OctetStringEncoder(),
useful.GeneralizedTime.typeId: OctetStringEncoder(),
useful.UTCTime.typeId: OctetStringEncoder()
}
class Encoder(object):
# noinspection PyDefaultArgument
def __init__(self, tagMap, typeMap={}):
self.__tagMap = tagMap
self.__typeMap = typeMap
def __call__(self, value, **options):
if not isinstance(value, base.Asn1Item):
raise error.PyAsn1Error('value is not valid (should be an instance of an ASN.1 Item)')
if LOG:
debug.scope.push(type(value).__name__)
LOG('encoder called for type %s <%s>' % (type(value).__name__, value.prettyPrint()))
tagSet = value.tagSet
try:
concreteEncoder = self.__typeMap[value.typeId]
except KeyError:
# use base type for codec lookup to recover untagged types
baseTagSet = tag.TagSet(value.tagSet.baseTag, value.tagSet.baseTag)
try:
concreteEncoder = self.__tagMap[baseTagSet]
except KeyError:
raise error.PyAsn1Error('No encoder for %s' % (value,))
if LOG:
LOG('using value codec %s chosen by %s' % (concreteEncoder.__class__.__name__, tagSet))
pyObject = concreteEncoder.encode(value, self, **options)
if LOG:
LOG('encoder %s produced: %s' % (type(concreteEncoder).__name__, repr(pyObject)))
debug.scope.pop()
return pyObject
#: Turns ASN.1 object into a Python built-in type object(s).
#:
#: Takes any ASN.1 object (e.g. :py:class:`~pyasn1.type.base.PyAsn1Item` derivative)
#: walks all its components recursively and produces a Python built-in type or a tree
#: of those.
#:
#: One exception is that instead of :py:class:`dict`, the :py:class:`OrderedDict`
#: can be produced (whenever available) to preserve ordering of the components
#: in ASN.1 SEQUENCE.
#:
#: Parameters
#: ----------
# asn1Value: any pyasn1 object (e.g. :py:class:`~pyasn1.type.base.PyAsn1Item` derivative)
#: pyasn1 object to encode (or a tree of them)
#:
#: Returns
#: -------
#: : :py:class:`object`
#: Python built-in type instance (or a tree of them)
#:
#: Raises
#: ------
#: ~pyasn1.error.PyAsn1Error
#: On encoding errors
#:
#: Examples
#: --------
#: Encode ASN.1 value object into native Python types
#:
#: .. code-block:: pycon
#:
#: >>> seq = SequenceOf(componentType=Integer())
#: >>> seq.extend([1, 2, 3])
#: >>> encode(seq)
#: [1, 2, 3]
#:
encode = Encoder(tagMap, typeMap)
Zerion Mini Shell 1.0