# Base classes for ASN.1 types
try:
from sys import version_info
except ImportError:
version_info = (0, 0) # a really early version
from operator import getslice,setslice,delslice
from string import join
from types import SliceType
from pyasn1.type import constraint
from pyasn1 import error
class Asn1Item: pass
class Asn1ItemBase(Asn1Item):
# Set of tags for this ASN.1 type
tagSet = ()
# A list of constraint.Constraint instances for checking values
subtypeSpec = constraint.ConstraintsIntersection()
def __init__(self, tagSet=None, subtypeSpec=None):
if tagSet is None:
self._tagSet = self.tagSet
else:
self._tagSet = tagSet
if subtypeSpec is None:
self._subtypeSpec = self.subtypeSpec
else:
self._subtypeSpec = subtypeSpec
def _verifySubtypeSpec(self, value, idx=None):
self._subtypeSpec(value, idx)
def getSubtypeSpec(self): return self._subtypeSpec
def getTagSet(self): return self._tagSet
def getTypeMap(self): return { self._tagSet: self }
def isSameTypeWith(self, other):
return self is other or \
self._tagSet == other.getTagSet() and \
self._subtypeSpec == other.getSubtypeSpec()
def isSuperTypeOf(self, other):
"""Returns true if argument is a ASN1 subtype of ourselves"""
return self._tagSet.isSuperTagSetOf(other.getTagSet()) and \
self._subtypeSpec.isSuperTypeOf(other.getSubtypeSpec())
class __NoValue:
def __getattr__(self, attr):
raise error.PyAsn1Error('No value for %s()' % attr)
noValue = __NoValue()
# Base class for "simple" ASN.1 objects. These are immutable.
class AbstractSimpleAsn1Item(Asn1ItemBase):
defaultValue = noValue
def __init__(self, value=None, tagSet=None, subtypeSpec=None):
Asn1ItemBase.__init__(self, tagSet, subtypeSpec)
if value is None or value is noValue:
value = self.defaultValue
if value is None or value is noValue:
self.__hashedValue = value = noValue
else:
value = self.prettyIn(value)
self._verifySubtypeSpec(value)
self.__hashedValue = hash(value)
self._value = value
def __repr__(self):
if self._value is noValue:
return self.__class__.__name__ + '()'
else:
return self.__class__.__name__ + '(' + repr(
self.prettyOut(self._value)
) + ')'
def __str__(self): return str(self._value)
def __cmp__(self, value): return cmp(self._value, value)
def __hash__(self): return self.__hashedValue
def __nonzero__(self):
if self._value: return 1
else: return 0
def clone(self, value=None, tagSet=None, subtypeSpec=None):
if value is None and tagSet is None and subtypeSpec is None:
return self
if value is None:
value = self._value
if tagSet is None:
tagSet = self._tagSet
if subtypeSpec is None:
subtypeSpec = self._subtypeSpec
return self.__class__(value, tagSet, subtypeSpec)
def subtype(self, value=None, implicitTag=None, explicitTag=None,
subtypeSpec=None):
if value is None:
value = self._value
if implicitTag is not None:
tagSet = self._tagSet.tagImplicitly(implicitTag)
elif explicitTag is not None:
tagSet = self._tagSet.tagExplicitly(explicitTag)
else:
tagSet = self._tagSet
if subtypeSpec is None:
subtypeSpec = self._subtypeSpec
else:
subtypeSpec = subtypeSpec + self._subtypeSpec
return self.__class__(value, tagSet, subtypeSpec)
def prettyIn(self, value): return value
def prettyOut(self, value): return str(value)
def prettyPrint(self, scope=0): return self.prettyOut(self._value)
# XXX Compatibility stub
def prettyPrinter(self, scope=0): return self.prettyPrint(scope)
#
# Constructed types:
# * There are five of them: Sequence, SequenceOf/SetOf, Set and Choice
# * ASN1 types and values are represened by Python class instances
# * Value initialization is made for defaulted components only
# * Primary method of component addressing is by-position. Data model for base
# type is Python sequence. Additional type-specific addressing methods
# may be implemented for particular types.
# * SequenceOf and SetOf types do not implement any additional methods
# * Sequence, Set and Choice types also implement by-identifier addressing
# * Sequence, Set and Choice types also implement by-asn1-type (tag) addressing
# * Sequence and Set types may include optional and defaulted
# components
# * Constructed types hold a reference to component types used for value
# verification and ordering.
# * Component type is a scalar type for SequenceOf/SetOf types and a list
# of types for Sequence/Set/Choice.
#
class AbstractConstructedAsn1Item(Asn1ItemBase):
componentType = None
sizeSpec = constraint.ConstraintsIntersection()
def __init__(self, componentType=None, tagSet=None,
subtypeSpec=None, sizeSpec=None):
Asn1ItemBase.__init__(self, tagSet, subtypeSpec)
if componentType is None:
self._componentType = self.componentType
else:
self._componentType = componentType
if sizeSpec is None:
self._sizeSpec = self.sizeSpec
else:
self._sizeSpec = sizeSpec
self._componentValues = []
def __repr__(self):
r = self.__class__.__name__ + '()'
for idx in range(len(self)):
if self._componentValues[idx] is None:
continue
r = r + '.setComponentByPosition(%s, %s)' % (
idx, repr(self._componentValues[idx])
)
return r
def __cmp__(self, other): return cmp(self._componentValues, other)
def getComponentTypeMap(self):
raise error.PyAsn1Error('Method not implemented')
def _cloneComponentValues(self, myClone, cloneValueFlag): pass
def clone(self, tagSet=None, subtypeSpec=None, sizeSpec=None,
cloneValueFlag=None):
if tagSet is None:
tagSet = self._tagSet
if subtypeSpec is None:
subtypeSpec = self._subtypeSpec
if sizeSpec is None:
sizeSpec = self._sizeSpec
r = self.__class__(self._componentType, tagSet, subtypeSpec, sizeSpec)
if cloneValueFlag:
self._cloneComponentValues(r, cloneValueFlag)
return r
def subtype(self, implicitTag=None, explicitTag=None, subtypeSpec=None,
sizeSpec=None, cloneValueFlag=None):
if implicitTag is not None:
tagSet = self._tagSet.tagImplicitly(implicitTag)
elif explicitTag is not None:
tagSet = self._tagSet.tagExplicitly(explicitTag)
else:
tagSet = self._tagSet
if subtypeSpec is None:
subtypeSpec = self._subtypeSpec
else:
subtypeSpec = subtypeSpec + self._subtypeSpec
if sizeSpec is None:
sizeSpec = self._sizeSpec
else:
sizeSpec = sizeSpec + self._sizeSpec
r = self.__class__(self._componentType, tagSet, subtypeSpec, sizeSpec)
if cloneValueFlag:
self._cloneComponentValues(r, cloneValueFlag)
return r
def _verifyComponent(self, idx, value): pass
def verifySizeSpec(self): self._sizeSpec(self)
def getComponentByPosition(self, idx):
raise error.PyAsn1Error('Method not implemented')
def setComponentByPosition(self, idx, value):
raise error.PyAsn1Error('Method not implemented')
def getComponentType(self): return self._componentType
def __getitem__(self, idx): return self._componentValues[idx]
def __len__(self): return len(self._componentValues)
def clear(self): self._componentValues = []
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