def readObjectIdentifier(s, oid):
"""
@summary: read object identifier
@param oid: must be a tuple of 6 elements
@param s: Stream
@return: true if oid is same as in stream
"""
size = readLength(s)
if size != 5:
raise InvalidValue("size of stream oid is wrong %d != 5" % size)
a_oid = [0, 0, 0, 0, 0, 0]
t12 = UInt8()
s.readType(t12)
a_oid[0] = t12.value >> 4
a_oid[1] = t12.value & 0x0f
s.readType(t12)
a_oid[2] = t12.value
s.readType(t12)
a_oid[3] = t12.value
s.readType(t12)
a_oid[4] = t12.value
s.readType(t12)
a_oid[5] = t12.value
if list(oid) != a_oid:
raise InvalidExpectedDataException("invalid object identifier")
def __setValue__(self, value):
"""
@summary: Check if new value respect type declaration
Ex: UInt8 can be > 256
@param value: new value (raw python type | lambda | function)
@raise InvalidValue: if value doesn't respect type range
@see: CallableValue.__setValue__
"""
#check static value range
if not callable(value) and not self.isInRange(value):
raise InvalidValue("value is out of range for %s" % self.__class__)
CallableValue.__setValue__(self, value)
def readDomainParams(self, s):
"""
@summary: Read domain parameters structure
@param s: {Stream}
@return: {Tuple} (max_channels, max_users, max_tokens, max_pdu_size)
"""
if not ber.readUniversalTag(s, ber.Tag.BER_TAG_SEQUENCE, True):
raise InvalidValue("bad BER tags")
ber.readLength(s) #length
max_channels = ber.readInteger(s)
max_users = ber.readInteger(s)
max_tokens = ber.readInteger(s)
ber.readInteger(s)
ber.readInteger(s)
ber.readInteger(s)
max_pdu_size = ber.readInteger(s)
ber.readInteger(s)
return (max_channels, max_users, max_tokens, max_pdu_size)
def readOctetStream(s, octetStream, minValue=0):
"""
@summary: read string as octet stream and compare with octetStream
@param octetStream: compare stream
@param s: Stream
@param minValue: min value
@return: if stream read from s is equal to octetStream
"""
size = readLength(s) + minValue
if size != len(octetStream):
raise InvalidValue("incompatible size %d != %d" (len(octetStream),
size))
for i in range(0, size):
c = UInt8()
s.readType(c)
if ord(octetStream[i]) != c.value:
return False
return True
def readInteger(s):
"""
@summary: read interger per format from stream
@param s: Stream
@return: python int or long
@raise InvalidValue: if size of integer is not correct
"""
result = None
size = readLength(s)
if size == 1:
result = UInt8()
elif size == 2:
result = UInt16Be()
elif size == 4:
result = UInt32Be()
else:
raise InvalidValue("invalid integer size %d" % size)
s.readType(result)
return result.value
def __getValue__(self):
"""
@summary: Check value if match range of type
And apply sign
Ex: UInt8 can be > 255
@return: Python value wrap into type
@raise InvalidValue: if value doesn't respect type range
@see: CallableValue.__getValue__
"""
value = CallableValue.__getValue__(self)
#check value now because it can be an callable value
#and evaluate a this time
if not self.isInRange(value):
raise InvalidValue("value is out of range for %s" % self.__class__)
if self._signed:
return value
else:
return value & self.mask()
def read(self, s):
old = deepcopy(self)
oldRead(self, s)
if self != old:
raise InvalidValue("CheckValueOnRead %s != %s" % (self, old))