class Null(OctetString):
defaultValue = ''.encode() # This is tightly constrained
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x05))
subtypeSpec = OctetString.subtypeSpec + constraint.SingleValueConstraint(
''.encode())
class ObjectIdentifier(base.AbstractSimpleAsn1Item):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x06))
def __add__(self, other):
return self.clone(self._value + other)
def __radd__(self, other):
return self.clone(other + self._value)
def asTuple(self):
return self._value
# Sequence object protocol
def __len__(self):
if self._len is None:
self._len = len(self._value)
return self._len
def __getitem__(self, i):
if isinstance(i, slice):
return self.clone(operator.getitem(self._value, i))
else:
return self._value[i]
def __str__(self):
return self.prettyPrint()
def index(self, suboid):
return self._value.index(suboid)
def isPrefixOf(self, value):
"""Returns true if argument OID resides deeper in the OID tree"""
l = len(self)
if l <= len(value):
if self._value[:l] == value[:l]:
return 1
return 0
def prettyIn(self, value):
"""Dotted -> tuple of numerics OID converter"""
if isinstance(value, tuple):
pass
elif isinstance(value, ObjectIdentifier):
return tuple(value)
elif isinstance(value, str):
r = []
for element in [x for x in value.split('.') if x != '']:
try:
r.append(int(element, 0))
except ValueError:
raise error.PyAsn1Error(
'Malformed Object ID %s at %s: %s' %
(str(value), self.__class__.__name__,
sys.exc_info()[1]))
value = tuple(r)
else:
try:
value = tuple(value)
except TypeError:
raise error.PyAsn1Error(
'Malformed Object ID %s at %s: %s' %
(str(value), self.__class__.__name__, sys.exc_info()[1]))
for x in value:
if not isinstance(x, intTypes) or x < 0:
raise error.PyAsn1Error('Invalid sub-ID in %s at %s' %
(value, self.__class__.__name__))
return value
def prettyOut(self, value):
return '.'.join([str(x) for x in value])
class BitString(base.AbstractSimpleAsn1Item):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x03))
namedValues = namedval.NamedValues()
def __init__(self,
value=None,
tagSet=None,
subtypeSpec=None,
namedValues=None):
if namedValues is None:
self.__namedValues = self.namedValues
else:
self.__namedValues = namedValues
base.AbstractSimpleAsn1Item.__init__(self, value, tagSet, subtypeSpec)
def clone(self,
value=None,
tagSet=None,
subtypeSpec=None,
namedValues=None):
if value is None and tagSet is None and subtypeSpec is None \
and namedValues 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
if namedValues is None:
namedValues = self.__namedValues
return self.__class__(value, tagSet, subtypeSpec, namedValues)
def subtype(self,
value=None,
implicitTag=None,
explicitTag=None,
subtypeSpec=None,
namedValues=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
if namedValues is None:
namedValues = self.__namedValues
else:
namedValues = namedValues + self.__namedValues
return self.__class__(value, tagSet, subtypeSpec, namedValues)
def __str__(self):
return str(tuple(self))
# Immutable sequence object protocol
def __len__(self):
if self._len is None:
self._len = len(self._value)
return self._len
def __getitem__(self, i):
if isinstance(i, slice):
return self.clone(operator.getitem(self._value, i))
else:
return self._value[i]
def __add__(self, value):
return self.clone(self._value + value)
def __radd__(self, value):
return self.clone(value + self._value)
def __mul__(self, value):
return self.clone(self._value * value)
def __rmul__(self, value):
return self * value
def prettyIn(self, value):
r = []
if not value:
return ()
elif isinstance(value, str):
if value[0] == '\'':
if value[-2:] == '\'B':
for v in value[1:-2]:
if v == '0':
r.append(0)
elif v == '1':
r.append(1)
else:
raise error.PyAsn1Error(
'Non-binary BIT STRING initializer %s' % (v, ))
return tuple(r)
elif value[-2:] == '\'H':
for v in value[1:-2]:
i = 4
v = int(v, 16)
while i:
i = i - 1
r.append((v >> i) & 0x01)
return tuple(r)
else:
raise error.PyAsn1Error(
'Bad BIT STRING value notation %s' % (value, ))
else:
for i in value.split(','):
j = self.__namedValues.getValue(i)
if j is None:
raise error.PyAsn1Error(
'Unknown bit identifier \'%s\'' % (i, ))
if j >= len(r):
r.extend([0] * (j - len(r) + 1))
r[j] = 1
return tuple(r)
elif isinstance(value, (tuple, list)):
r = tuple(value)
for b in r:
if b and b != 1:
raise error.PyAsn1Error(
'Non-binary BitString initializer \'%s\'' % (r, ))
return r
elif isinstance(value, BitString):
return tuple(value)
else:
raise error.PyAsn1Error('Bad BitString initializer type \'%s\'' %
(value, ))
def prettyOut(self, value):
return '\"\'%s\'B\"' % ''.join([str(x) for x in value])
class OctetString(base.AbstractSimpleAsn1Item):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x04))
defaultBinValue = defaultHexValue = base.noValue
encoding = 'us-ascii'
def __init__(self,
value=None,
tagSet=None,
subtypeSpec=None,
encoding=None,
binValue=None,
hexValue=None):
if encoding is None:
self._encoding = self.encoding
else:
self._encoding = encoding
if binValue is not None:
value = self.fromBinaryString(binValue)
if hexValue is not None:
value = self.fromHexString(hexValue)
if value is None or value is base.noValue:
value = self.defaultHexValue
if value is None or value is base.noValue:
value = self.defaultBinValue
self.__intValue = None
base.AbstractSimpleAsn1Item.__init__(self, value, tagSet, subtypeSpec)
def clone(self,
value=None,
tagSet=None,
subtypeSpec=None,
encoding=None,
binValue=None,
hexValue=None):
if value is None and tagSet is None and subtypeSpec is None and \
encoding is None and binValue is None and hexValue is None:
return self
if value is None and binValue is None and hexValue is None:
value = self._value
if tagSet is None:
tagSet = self._tagSet
if subtypeSpec is None:
subtypeSpec = self._subtypeSpec
if encoding is None:
encoding = self._encoding
return self.__class__(value, tagSet, subtypeSpec, encoding, binValue,
hexValue)
if sys.version_info[0] <= 2:
def prettyIn(self, value):
if isinstance(value, str):
return value
elif isinstance(value, (tuple, list)):
try:
return ''.join([chr(x) for x in value])
except ValueError:
raise error.PyAsn1Error(
'Bad OctetString initializer \'%s\'' % (value, ))
else:
return str(value)
else:
def prettyIn(self, value):
if isinstance(value, bytes):
return value
elif isinstance(value, OctetString):
return value.asOctets()
elif isinstance(value, (tuple, list, map)):
try:
return bytes(value)
except ValueError:
raise error.PyAsn1Error(
'Bad OctetString initializer \'%s\'' % (value, ))
else:
try:
return str(value).encode(self._encoding)
except UnicodeEncodeError:
raise error.PyAsn1Error(
'Can\'t encode string \'%s\' with \'%s\' codec' %
(value, self._encoding))
def fromBinaryString(self, value):
bitNo = 8
byte = 0
r = ()
for v in value:
if bitNo:
bitNo = bitNo - 1
else:
bitNo = 7
r = r + (byte, )
byte = 0
if v == '0':
v = 0
elif v == '1':
v = 1
else:
raise error.PyAsn1Error(
'Non-binary OCTET STRING initializer %s' % (v, ))
byte = byte | (v << bitNo)
return octets.ints2octs(r + (byte, ))
def fromHexString(self, value):
r = p = ()
for v in value:
if p:
r = r + (int(p + v, 16), )
p = ()
else:
p = v
if p:
r = r + (int(p + '0', 16), )
return octets.ints2octs(r)
def prettyOut(self, value):
if sys.version_info[0] <= 2:
numbers = tuple([ord(x) for x in value])
else:
numbers = tuple(value)
if [x for x in numbers if x < 32 or x > 126]:
return '0x' + ''.join(['%.2x' % x for x in numbers])
else:
return str(value)
def __repr__(self):
if self._value is base.noValue:
return self.__class__.__name__ + '()'
if [x for x in self.asNumbers() if x < 32 or x > 126]:
return self.__class__.__name__ + '(hexValue=\'' + ''.join(
['%.2x' % x for x in self.asNumbers()]) + '\')'
else:
return self.__class__.__name__ + '(\'' + self.prettyOut(
self._value) + '\')'
if sys.version_info[0] <= 2:
def __str__(self):
return str(self._value)
def __unicode__(self):
return self._value.decode(self._encoding, 'ignore')
def asOctets(self):
return self._value
def asNumbers(self):
if self.__intValue is None:
self.__intValue = tuple([ord(x) for x in self._value])
return self.__intValue
else:
def __str__(self):
return self._value.decode(self._encoding, 'ignore')
def __bytes__(self):
return self._value
def asOctets(self):
return self._value
def asNumbers(self):
if self.__intValue is None:
self.__intValue = tuple(self._value)
return self.__intValue
# Immutable sequence object protocol
def __len__(self):
if self._len is None:
self._len = len(self._value)
return self._len
def __getitem__(self, i):
if isinstance(i, slice):
return self.clone(operator.getitem(self._value, i))
else:
return self._value[i]
def __add__(self, value):
return self.clone(self._value + self.prettyIn(value))
def __radd__(self, value):
return self.clone(self.prettyIn(value) + self._value)
def __mul__(self, value):
return self.clone(self._value * value)
def __rmul__(self, value):
return self * value
class EndOfOctets(base.AbstractSimpleAsn1Item):
defaultValue = 0
tagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x00)
)
class Boolean(Integer):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x01), )
subtypeSpec = Integer.subtypeSpec + constraint.SingleValueConstraint(0, 1)
namedValues = Integer.namedValues.clone(('False', 0), ('True', 1))
class BMPString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 30)
)
encoding = "utf-16-be"
class SetOf(base.AbstractConstructedAsn1Item):
componentType = None
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatConstructed, 0x11))
typeId = 1
def _cloneComponentValues(self, myClone, cloneValueFlag):
idx = 0
l = len(self._componentValues)
while idx < l:
c = self._componentValues[idx]
if c is not None:
if isinstance(c, base.AbstractConstructedAsn1Item):
myClone.setComponentByPosition(
idx, c.clone(cloneValueFlag=cloneValueFlag))
else:
myClone.setComponentByPosition(idx, c.clone())
idx = idx + 1
def _verifyComponent(self, idx, value):
if self._componentType is not None and \
not self._componentType.isSuperTypeOf(value):
raise error.PyAsn1Error('Component type error %s' % (value, ))
def getComponentByPosition(self, idx):
return self._componentValues[idx]
def setComponentByPosition(self, idx, value=None, verifyConstraints=True):
l = len(self._componentValues)
if idx >= l:
self._componentValues = self._componentValues + (idx - l +
1) * [None]
if value is None:
if self._componentValues[idx] is None:
if self._componentType is None:
raise error.PyAsn1Error('Component type not defined')
self._componentValues[idx] = self._componentType.clone()
self._componentValuesSet = self._componentValuesSet + 1
return self
elif not isinstance(value, base.Asn1Item):
if self._componentType is None:
raise error.PyAsn1Error('Component type not defined')
if isinstance(self._componentType, base.AbstractSimpleAsn1Item):
value = self._componentType.clone(value=value)
else:
raise error.PyAsn1Error('Instance value required')
if verifyConstraints:
if self._componentType is not None:
self._verifyComponent(idx, value)
self._verifySubtypeSpec(value, idx)
if self._componentValues[idx] is None:
self._componentValuesSet = self._componentValuesSet + 1
self._componentValues[idx] = value
return self
def getComponentTagMap(self):
if self._componentType is not None:
return self._componentType.getTagMap()
def prettyPrint(self, scope=0):
scope = scope + 1
r = self.__class__.__name__ + ':\n'
for idx in range(len(self._componentValues)):
r = r + ' ' * scope
if self._componentValues[idx] is None:
r = r + '<empty>'
else:
r = r + self._componentValues[idx].prettyPrint(scope)
return r
class VisibleString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 26)
)
class GeneralString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 27)
)
class GraphicString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 25)
)
class UTF8String(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 12)
)
encoding = "utf-8"
class TeletexString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 20)
)
class Real(base.AbstractSimpleAsn1Item):
try:
_plusInf = float('inf')
_minusInf = float('-inf')
_inf = (_plusInf, _minusInf)
except ValueError:
# Infinity support is platform and Python dependent
_plusInf = _minusInf = None
_inf = ()
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x09))
def __normalizeBase10(self, value):
m, b, e = value
while m and m % 10 == 0:
m = m / 10
e = e + 1
return m, b, e
def prettyIn(self, value):
if isinstance(value, tuple) and len(value) == 3:
for d in value:
if not isinstance(d, intTypes):
raise error.PyAsn1Error('Lame Real value syntax: %s' %
(value, ))
if value[1] not in (2, 10):
raise error.PyAsn1Error('Prohibited base for Real value: %s' %
(value[1], ))
if value[1] == 10:
value = self.__normalizeBase10(value)
return value
elif isinstance(value, intTypes):
return self.__normalizeBase10((value, 10, 0))
elif isinstance(value, float):
if self._inf and value in self._inf:
return value
else:
e = 0
while int(value) != value:
value = value * 10
e = e - 1
return self.__normalizeBase10((int(value), 10, e))
elif isinstance(value, Real):
return tuple(value)
elif isinstance(value, str): # handle infinite literal
try:
return float(value)
except ValueError:
pass
raise error.PyAsn1Error('Bad real value syntax: %s' % (value, ))
def prettyOut(self, value):
if value in self._inf:
return '\'%s\'' % value
else:
return str(value)
def isPlusInfinity(self):
return self._value == self._plusInf
def isMinusInfinity(self):
return self._value == self._minusInf
def isInfinity(self):
return self._value in self._inf
def __str__(self):
return str(float(self))
def __add__(self, value):
return self.clone(float(self) + value)
def __radd__(self, value):
return self + value
def __mul__(self, value):
return self.clone(float(self) * value)
def __rmul__(self, value):
return self * value
def __sub__(self, value):
return self.clone(float(self) - value)
def __rsub__(self, value):
return self.clone(value - float(self))
def __mod__(self, value):
return self.clone(float(self) % value)
def __rmod__(self, value):
return self.clone(value % float(self))
def __pow__(self, value, modulo=None):
return self.clone(pow(float(self), value, modulo))
def __rpow__(self, value):
return self.clone(pow(value, float(self)))
if sys.version_info[0] <= 2:
def __div__(self, value):
return self.clone(float(self) / value)
def __rdiv__(self, value):
return self.clone(value / float(self))
else:
def __truediv__(self, value):
return self.clone(float(self) / value)
def __rtruediv__(self, value):
return self.clone(value / float(self))
def __divmod__(self, value):
return self.clone(float(self) // value)
def __rdivmod__(self, value):
return self.clone(value // float(self))
def __int__(self):
return int(float(self))
if sys.version_info[0] <= 2:
def __long__(self):
return long(float(self))
def __float__(self):
if self._value in self._inf:
return self._value
else:
return float(self._value[0] * pow(self._value[1], self._value[2]))
def __abs__(self):
return abs(float(self))
def __lt__(self, value):
return float(self) < value
def __le__(self, value):
return float(self) <= value
def __eq__(self, value):
return float(self) == value
def __ne__(self, value):
return float(self) != value
def __gt__(self, value):
return float(self) > value
def __ge__(self, value):
return float(self) >= value
if sys.version_info[0] <= 2:
def __nonzero__(self):
return bool(float(self))
else:
def __bool__(self):
return bool(float(self))
__hash__ = base.AbstractSimpleAsn1Item.__hash__
def __getitem__(self, idx):
if self._value in self._inf:
raise error.PyAsn1Error('Invalid infinite value operation')
else:
return self._value[idx]
class NumericString(univ.OctetString):
tagSet = univ.OctetString.tagSet.tagImplicitly(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 18)
)
class Enumerated(Integer):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x0A))
class Integer(base.AbstractSimpleAsn1Item):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatSimple, 0x02))
namedValues = namedval.NamedValues()
def __init__(self,
value=None,
tagSet=None,
subtypeSpec=None,
namedValues=None):
if namedValues is None:
self.__namedValues = self.namedValues
else:
self.__namedValues = namedValues
base.AbstractSimpleAsn1Item.__init__(self, value, tagSet, subtypeSpec)
def __and__(self, value):
return self.clone(self._value & value)
def __rand__(self, value):
return self.clone(value & self._value)
def __or__(self, value):
return self.clone(self._value | value)
def __ror__(self, value):
return self.clone(value | self._value)
def __xor__(self, value):
return self.clone(self._value ^ value)
def __rxor__(self, value):
return self.clone(value ^ self._value)
def __lshift__(self, value):
return self.clone(self._value << value)
def __rshift__(self, value):
return self.clone(self._value >> value)
def __add__(self, value):
return self.clone(self._value + value)
def __radd__(self, value):
return self.clone(value + self._value)
def __sub__(self, value):
return self.clone(self._value - value)
def __rsub__(self, value):
return self.clone(value - self._value)
def __mul__(self, value):
return self.clone(self._value * value)
def __rmul__(self, value):
return self.clone(value * self._value)
def __mod__(self, value):
return self.clone(self._value % value)
def __rmod__(self, value):
return self.clone(value % self._value)
def __pow__(self, value, modulo=None):
return self.clone(pow(self._value, value, modulo))
def __rpow__(self, value):
return self.clone(pow(value, self._value))
if sys.version_info[0] <= 2:
def __div__(self, value):
return self.clone(self._value // value)
def __rdiv__(self, value):
return self.clone(value // self._value)
else:
def __truediv__(self, value):
return self.clone(self._value / value)
def __rtruediv__(self, value):
return self.clone(value / self._value)
def __divmod__(self, value):
return self.clone(self._value // value)
def __rdivmod__(self, value):
return self.clone(value // self._value)
__hash__ = base.AbstractSimpleAsn1Item.__hash__
def __int__(self):
return int(self._value)
if sys.version_info[0] <= 2:
def __long__(self):
return long(self._value)
def __float__(self):
return float(self._value)
def __abs__(self):
return abs(self._value)
def __index__(self):
return int(self._value)
def __lt__(self, value):
return self._value < value
def __le__(self, value):
return self._value <= value
def __eq__(self, value):
return self._value == value
def __ne__(self, value):
return self._value != value
def __gt__(self, value):
return self._value > value
def __ge__(self, value):
return self._value >= value
def prettyIn(self, value):
if not isinstance(value, str):
try:
return int(value)
except:
raise error.PyAsn1Error('Can\'t coerce %s into integer: %s' %
(value, sys.exc_info()[1]))
r = self.__namedValues.getValue(value)
if r is not None:
return r
try:
return int(value)
except:
raise error.PyAsn1Error('Can\'t coerce %s into integer: %s' %
(value, sys.exc_info()[1]))
def prettyOut(self, value):
r = self.__namedValues.getName(value)
return r is None and str(value) or repr(r)
def getNamedValues(self):
return self.__namedValues
def clone(self,
value=None,
tagSet=None,
subtypeSpec=None,
namedValues=None):
if value is None and tagSet is None and subtypeSpec is None \
and namedValues 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
if namedValues is None:
namedValues = self.__namedValues
return self.__class__(value, tagSet, subtypeSpec, namedValues)
def subtype(self,
value=None,
implicitTag=None,
explicitTag=None,
subtypeSpec=None,
namedValues=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
if namedValues is None:
namedValues = self.__namedValues
else:
namedValues = namedValues + self.__namedValues
return self.__class__(value, tagSet, subtypeSpec, namedValues)
class SequenceOf(SetOf):
tagSet = baseTagSet = tag.initTagSet(
tag.Tag(tag.tagClassUniversal, tag.tagFormatConstructed, 0x10))
typeId = 2
def __call__(self,
substrate,
asn1Spec=None,
tagSet=None,
length=None,
state=stDecodeTag,
recursiveFlag=1,
substrateFun=None):
if debug.logger & debug.flagDecoder:
debug.logger(
'decoder called at scope %s with state %d, working with up to %d octets of substrate: %s'
%
(debug.scope, state, len(substrate), debug.hexdump(substrate)))
fullSubstrate = substrate
while state != stStop:
if state == stDecodeTag:
# Decode tag
if not substrate:
raise error.SubstrateUnderrunError(
'Short octet stream on tag decoding')
if not isOctetsType(substrate) and \
not isinstance(substrate, univ.OctetString):
raise error.PyAsn1Error('Bad octet stream type')
firstOctet = substrate[0]
substrate = substrate[1:]
if firstOctet in self.__tagCache:
lastTag = self.__tagCache[firstOctet]
else:
t = oct2int(firstOctet)
tagClass = t & 0xC0
tagFormat = t & 0x20
tagId = t & 0x1F
if tagId == 0x1F:
tagId = 0
while 1:
if not substrate:
raise error.SubstrateUnderrunError(
'Short octet stream on long tag decoding')
t = oct2int(substrate[0])
tagId = tagId << 7 | (t & 0x7F)
substrate = substrate[1:]
if not t & 0x80:
break
lastTag = tag.Tag(tagClass=tagClass,
tagFormat=tagFormat,
tagId=tagId)
if tagId < 31:
# cache short tags
self.__tagCache[firstOctet] = lastTag
if tagSet is None:
if firstOctet in self.__tagSetCache:
tagSet = self.__tagSetCache[firstOctet]
else:
# base tag not recovered
tagSet = tag.TagSet((), lastTag)
if firstOctet in self.__tagCache:
self.__tagSetCache[firstOctet] = tagSet
else:
tagSet = lastTag + tagSet
state = stDecodeLength
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'tag decoded into %r, decoding length' % tagSet)
if state == stDecodeLength:
# Decode length
if not substrate:
raise error.SubstrateUnderrunError(
'Short octet stream on length decoding')
firstOctet = oct2int(substrate[0])
if firstOctet == 128:
size = 1
length = -1
elif firstOctet < 128:
length, size = firstOctet, 1
else:
size = firstOctet & 0x7F
# encoded in size bytes
length = 0
lengthString = substrate[1:size + 1]
# missing check on maximum size, which shouldn't be a
# problem, we can handle more than is possible
if len(lengthString) != size:
raise error.SubstrateUnderrunError(
'%s<%s at %s' % (size, len(lengthString), tagSet))
for char in lengthString:
length = (length << 8) | oct2int(char)
size = size + 1
substrate = substrate[size:]
if length != -1 and len(substrate) < length:
raise error.SubstrateUnderrunError(
'%d-octet short' % (length - len(substrate)))
state = stGetValueDecoder
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'value length decoded into %d, payload substrate is: %s' %
(length,
debug.hexdump(length == -1 and substrate
or substrate[:length])))
if state == stGetValueDecoder:
if asn1Spec is None:
state = stGetValueDecoderByTag
else:
state = stGetValueDecoderByAsn1Spec
#
# There're two ways of creating subtypes in ASN.1 what influences
# decoder operation. These methods are:
# 1) Either base types used in or no IMPLICIT tagging has been
# applied on subtyping.
# 2) Subtype syntax drops base type information (by means of
# IMPLICIT tagging.
# The first case allows for complete tag recovery from substrate
# while the second one requires original ASN.1 type spec for
# decoding.
#
# In either case a set of tags (tagSet) is coming from substrate
# in an incremental, tag-by-tag fashion (this is the case of
# EXPLICIT tag which is most basic). Outermost tag comes first
# from the wire.
#
if state == stGetValueDecoderByTag:
if tagSet in self.__tagMap:
concreteDecoder = self.__tagMap[tagSet]
else:
concreteDecoder = None
if concreteDecoder:
state = stDecodeValue
else:
_k = tagSet[:1]
if _k in self.__tagMap:
concreteDecoder = self.__tagMap[_k]
else:
concreteDecoder = None
if concreteDecoder:
state = stDecodeValue
else:
state = stTryAsExplicitTag
if debug.logger and debug.logger & debug.flagDecoder:
debug.logger(
'codec %s chosen by a built-in type, decoding %s' %
(concreteDecoder and concreteDecoder.__class__.__name__
or "<none>", state == stDecodeValue and 'value'
or 'as explicit tag'))
debug.scope.push(
concreteDecoder is None and '?'
or concreteDecoder.protoComponent.__class__.__name__)
if state == stGetValueDecoderByAsn1Spec:
if isinstance(asn1Spec, (dict, tagmap.TagMap)):
if tagSet in asn1Spec:
__chosenSpec = asn1Spec[tagSet]
else:
__chosenSpec = None
if debug.logger and debug.logger & debug.flagDecoder:
debug.logger('candidate ASN.1 spec is a map of:')
for t, v in asn1Spec.getPosMap().items():
debug.logger(' %r -> %s' %
(t, v.__class__.__name__))
if asn1Spec.getNegMap():
debug.logger('but neither of: ')
for i in asn1Spec.getNegMap().items():
debug.logger(' %r -> %s' %
(t, v.__class__.__name__))
debug.logger(
'new candidate ASN.1 spec is %s, chosen by %r' %
(__chosenSpec is None and '<none>'
or __chosenSpec.__class__.__name__, tagSet))
else:
__chosenSpec = asn1Spec
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'candidate ASN.1 spec is %s' %
asn1Spec.__class__.__name__)
if __chosenSpec is not None and (
tagSet == __chosenSpec.getTagSet() or \
tagSet in __chosenSpec.getTagMap()
):
# use base type for codec lookup to recover untagged types
baseTagSet = __chosenSpec.baseTagSet
if __chosenSpec.typeId is not None and \
__chosenSpec.typeId in self.__typeMap:
# ambiguous type
concreteDecoder = self.__typeMap[__chosenSpec.typeId]
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'value decoder chosen for an ambiguous type by type ID %s'
% (__chosenSpec.typeId, ))
elif baseTagSet in self.__tagMap:
# base type or tagged subtype
concreteDecoder = self.__tagMap[baseTagSet]
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'value decoder chosen by base %r' % (baseTagSet, ))
else:
concreteDecoder = None
if concreteDecoder:
asn1Spec = __chosenSpec
state = stDecodeValue
else:
state = stTryAsExplicitTag
elif tagSet == self.__endOfOctetsTagSet:
concreteDecoder = self.__tagMap[tagSet]
state = stDecodeValue
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'end-of-octets found')
else:
concreteDecoder = None
state = stTryAsExplicitTag
if debug.logger and debug.logger & debug.flagDecoder:
debug.logger(
'codec %s chosen by ASN.1 spec, decoding %s' %
(state == stDecodeValue
and concreteDecoder.__class__.__name__
or "<none>", state == stDecodeValue and 'value'
or 'as explicit tag'))
debug.scope.push(__chosenSpec is None and '?'
or __chosenSpec.__class__.__name__)
if state == stTryAsExplicitTag:
if tagSet and \
tagSet[0][1] == tag.tagFormatConstructed and \
tagSet[0][0] != tag.tagClassUniversal:
# Assume explicit tagging
concreteDecoder = explicitTagDecoder
state = stDecodeValue
else:
concreteDecoder = None
state = self.defaultErrorState
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'codec %s chosen, decoding %s' %
(concreteDecoder and concreteDecoder.__class__.__name__
or "<none>", state == stDecodeValue and 'value'
or 'as failure'))
if state == stDumpRawValue:
concreteDecoder = self.defaultRawDecoder
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'codec %s chosen, decoding value' %
concreteDecoder.__class__.__name__)
state = stDecodeValue
if state == stDecodeValue:
if recursiveFlag == 0 and not substrateFun: # legacy
substrateFun = lambda a, b, c: (a, b[:c])
if length == -1: # indef length
value, substrate = concreteDecoder.indefLenValueDecoder(
fullSubstrate, substrate, asn1Spec, tagSet, length,
stGetValueDecoder, self, substrateFun)
else:
value, substrate = concreteDecoder.valueDecoder(
fullSubstrate, substrate, asn1Spec, tagSet, length,
stGetValueDecoder, self, substrateFun)
state = stStop
debug.logger and debug.logger & debug.flagDecoder and debug.logger(
'codec %s yields type %s, value:\n%s\n...remaining substrate is: %s'
% (concreteDecoder.__class__.__name__,
value.__class__.__name__, value.prettyPrint(),
substrate and debug.hexdump(substrate) or '<none>'))
if state == stErrorCondition:
raise error.PyAsn1Error('%r not in asn1Spec: %r' %
(tagSet, asn1Spec))
if debug.logger and debug.logger & debug.flagDecoder:
debug.scope.pop()
debug.logger('decoder left scope %s, call completed' % debug.scope)
return value, substrate
