def build(self):
"""
Build the packet
Adds padding to the data, adds the RID, PID, opcode, and checksum.
Parameters: None
Returns: Bytestring of the packet.
Raises: None
"""
# Construct the packet's data
# Do a TMR expansion where the data is replicated 3 times but not next to each other
# to avoid burst errors.
# if self.useFEC:
# data = self.data * 3
# else:
# data = self.data
data = self.data
padding = DataPacket.data_size - len(data)
data += DataPacket.padding_byte * padding
self.paddingSize = padding
packet = self.rid.to_bytes(
1, byteorder='big') + self.opcode + DataPacket.pid.to_bytes(
4, byteorder='big') + data
# If the packet is for download use safe checksum maker
if self.downloadPacketChecksum:
packet += self.generateDownloadChecksum(data)
else:
packet += generateChecksum(packet)
# After constructing the packet's contents, pad the end of the packet until we reach the max size.
return packet
def build(self):
"""
Override for the dummy packet's build.
Parameters: None
Returns: the packet's bytestring
Raises: None
"""
toSend = self.rid + self.opcode + self.data
return toSend + generateChecksum(toSend)
def checkValidity(fieldData, packetData):
logger.logInfo("Entered: checkValidity")
"""
Check to see if a packet is valid and not corrupt.
Parameters:
fieldData - dictonary returned by decodePacket
Returns: tuple of data
tuple[0] = True if the packet is good, False if corrupted
tuple[1] = the fieldData passed in or modified data
Raises: None
"""
# Figure out the data without the checksum
if fieldData:
if fieldData['TYPE'] == 'UNKNOWN':
isValid = False
fieldData = None
else:
packetString = bytes([
fieldData['route']
]) + fieldData['opcode'] + fieldData['contents']
isValid = fieldData['route'] in validRoutes and fieldData[
'checksum'] == generateChecksum(packetData[:-4])
if fieldData['TYPE'] == 'DATA':
pass
elif fieldData['TYPE'] == 'NORM':
#print("The tag of this packet is", fieldData['tag'].decode("utf-8"))
#print("FEILD DATA TAG:", fieldData['tag'])
validTag = checker.isValidTag(fieldData['tag'])
if isValid and not validTag:
logger.logSystem(
'Interpreter: A valid packet came in, but the tag was wrong. The packet is being dropped.'
)
isValid = isValid and validTag
elif fieldData['TYPE'] == 'DLACK':
# Honestly, I don't think there's anything to do here...
checker.clearTagList()
else:
isValid = False
logger.logInfo("Exited: checkValidity")
return isValid, fieldData
def finish(information):
"""
Finish the scaffold, remove the extension, and remove the extra padding by the last packet.
Parameters: information - all the data found in the NOOP! packet.
Returns: a tuple of values
tuple[0] = True or False if the checksums match from the calculated one and the file's reported checksum
tuple[1] = the filename of the downloaded file
Raises: None
"""
if UploadRequest.isActive():
information = information.split(b' ')
checksum = information[0]
paddingUsed = int.from_bytes(information[1], byteorder='big')
filename = information[2][:information[2].
find(DataPacket.padding_byte)].replace(
b'/', b'@').decode('ascii')
with open(TEMPPATH + filename + '.scaffold', 'rb+') as f:
info = f.read()
f.seek(0)
f.truncate()
if paddingUsed:
f.write(info[:-paddingUsed])
else:
f.write(info)
checksumMatch = checksum == generateChecksum(
open(TEMPPATH + filename + '.scaffold', 'rb').read())
try:
os.rename('{}{}.scaffold'.format(TEMPPATH, filename),
ROOTPATH + filename.replace('@', '/'))
os.rename('{}{}.nore'.format(TEMPPATH, filename),
"{}{}.nore".format(GRAVEPATH, filename))
except:
pass
return checksumMatch, UploadRequest.finished(filename)
def build(self):
"""
Build a packet out of the four chunks
Parameters: None
Returns: The bytestring of the packet
Raises: None
"""
if ChunkPacket.complete:
packet = b''
for chunk in ChunkPacket.chunks:
packet += chunk
if len(packet) != DataPacket.max_size:
self.logger.logSystem(
"Packet is not {} bytes! It is {} bytes!".format(
str(DataPacket.max_size), str(len(packet))),
str(packet)[50:])
#print("QUICK FIX IN QPACE FILE HANDLER")
packet = packet[(len(packet) - DataPacket.max_size):]
if (packet[-4:] != generateChecksum(packet[:-4])):
packet = b''
#print("THE DATA SEND ISN'T VALID:\nCHECKSUMS DON'T MATCH")
Command.PrivilegedPacket(
opcode=b"ERROR", plainText=b"ERROR OCCURING").send()
#else:
#print("QUICK FIX IS VALID")
ChunkPacket.chunks[:] = [] #reset chunks to empty
ChunkPacket.complete = False #reset copmlete to False
ChunkPacket.lastInputTime = None # reset the timer.
return packet
else:
#print('Packet is not complete yet.')
pass