111 lines
3.6 KiB
Python
111 lines
3.6 KiB
Python
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import logging
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LOG_LEVEL = logging.NOTSET
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MIN_BLKSIZE = 8
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DEF_BLKSIZE = 512
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MAX_BLKSIZE = 65536
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SOCK_TIMEOUT = 5
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MAX_DUPS = 20
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TIMEOUT_RETRIES = 5
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DEF_TFTP_PORT = 69
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# Initialize the logger.
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logging.basicConfig(
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level=LOG_LEVEL,
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format='%(asctime)s %(name)-12s %(levelname)-8s %(message)s',
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datefmt='%m-%d %H:%M:%S')
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# The logger used by this library. Feel free to clobber it with your own, if you like, as
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# long as it conforms to Python's logging.
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logger = logging.getLogger('tftpy')
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def tftpassert(condition, msg):
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"""This function is a simple utility that will check the condition
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passed for a false state. If it finds one, it throws a TftpException
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with the message passed. This just makes the code throughout cleaner
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by refactoring."""
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if not condition:
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raise TftpException, msg
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def setLogLevel(level):
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"""This function is a utility function for setting the internal log level.
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The log level defaults to logging.NOTSET, so unwanted output to stdout is
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not created."""
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global logger
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logger.setLevel(level)
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class TftpErrors(object):
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"""This class is a convenience for defining the common tftp error codes, and making
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them more readable in the code."""
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NotDefined = 0
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FileNotFound = 1
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AccessViolation = 2
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DiskFull = 3
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IllegalTftpOp = 4
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UnknownTID = 5
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FileAlreadyExists = 6
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NoSuchUser = 7
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FailedNegotiation = 8
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class TftpException(Exception):
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"""This class is the parent class of all exceptions regarding the handling
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of the TFTP protocol."""
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pass
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class TftpState(object):
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"""This class represents a particular state for a TFTP Session. It encapsulates a
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state, kind of like an enum. The states mean the following:
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nil - Client/Server - Session not yet established
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rrq - Client - Just sent RRQ in a download, waiting for response
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Server - Just received an RRQ
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wrq - Client - Just sent WRQ in an upload, waiting for response
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Server - Just received a WRQ
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dat - Client/Server - Transferring data
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oack - Client - Just received oack
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Server - Just sent OACK
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ack - Client - Acknowledged oack, awaiting response
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Server - Just received ACK to OACK
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err - Client/Server - Fatal problems, giving up
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fin - Client/Server - Transfer completed
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"""
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states = ['nil',
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'rrq',
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'wrq',
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'dat',
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'oack',
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'ack',
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'err',
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'fin']
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def __init__(self, state='nil'):
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self.state = state
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def getState(self):
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return self.__state
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def setState(self, state):
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if state in TftpState.states:
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self.__state = state
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state = property(getState, setState)
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class TftpSession(object):
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"""This class is the base class for the tftp client and server. Any shared
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code should be in this class."""
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def __init__(self):
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"""Class constructor. Note that the state property must be a TftpState
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object."""
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self.options = None
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self.state = TftpState()
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self.dups = 0
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self.errors = 0
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def senderror(self, sock, errorcode, address, port):
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"""This method uses the socket passed, and uses the errorcode, address and port to
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compose and send an error packet."""
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logger.debug("In senderror, being asked to send error %d to %s:%s"
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% (errorcode, address, port))
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errpkt = TftpPacketERR()
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errpkt.errorcode = errorcode
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self.sock.sendto(errpkt.encode().buffer, (address, port))
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