class Client:
# interface of this class is more or less compatible
# with org.apache.commons.net.ftp.FTPClient
# This interface does not provide additional error checking,
# however provides warnings.
def __init__(self, commandNet, dataNet):
self.commandNet = commandNet
self.dataNet = dataNet
self.machine = StateMachine(commandNet)
self.DATA_TRANSFER_CONFIRMATION_BUG = False
self.PASV_RESPONSE_READ_BUG = False
def setDataTransferConfirmationBug(self, value):
self.DATA_TRANSFER_CONFIRMATION_BUG = value
def setPasvResponseReadingBug(self, value):
self.PASV_RESPONSE_READ_BUG = value
def warn(self, message):
print "WARN %s" % message
def connect(self, host, port):
if self.machine.getState() != STATE_READY:
self.warn("Expecting STATE_READY")
return self.machine.connect(host, port)
def isConnected(self):
return self.machine.getState() != STATE_READY
def isLogged(self):
return (self.machine.getState() != STATE_READY
and self.machine.getState() != STATE_CONNECTED
and self.machine.getState() != STATE_WAITING_PASSWORD)
def login(self, username, password):
if self.machine.getState() != STATE_CONNECTED:
self.warn("Expecting STATE_CONNECTED")
suc = self.machine.user(username)
if not suc:
return False
# no password needed for some servers
if self.machine.getState() == STATE_LOGGED:
return True
## INJECTION
# Here WAS a bug found by simulation.
# If the following command fails, the state machine HAD stuck in WAITING_PASSWORD.
suc = self.machine.password(password)
if not suc:
self.machine.clearWaitingPasswordAfterError()
return suc
def listFiles(self):
if self.machine.getState() != STATE_LOGGED:
self.warn("Expecting STATE_LOGGED")
# todo: polish according to retrieveFile
suc = self.machine.pasv()
if not suc:
return None
dataSocket = self.machine.getDataSocket()
## INJECTION
# The transaction may go well (reponse code is OK) but the
# returned IP address and port may not be readable.
if not self.PASV_RESPONSE_READ_BUG:
if dataSocket is None:
self.machine.dataConnectionClearAfterError()
return None
else:
self.warn("PASV_RESPONSE_READ_BUG is active")
suc = self.dataNet.connect(dataSocket.hostname, dataSocket.port)
if not suc:
self.machine.dataConnectionClearAfterError()
return None
dataReader = self.dataNet.createNetworkReader()
self.machine.dataConnectionEstablished()
suc = self.machine.listing()
if suc:
data = dataReader.readAll()
suc2 = self.machine.transferSuccessfullyDone()
if not suc2:
self.machine.dataConnectionClearAfterError()
return None
return parseListing(data)
else:
self.machine.dataConnectionClearAfterError()
return None
def changeWorkingDirectory(self, directory):
if self.machine.getState() != STATE_LOGGED:
self.warn("Expecting STATE_LOGGED")
return self.machine.cwd(directory)
def logout(self):
if not self.isConnected():
self.warn("Expecting isConnected")
return False
return self.machine.quit()
def deleteFile(self, filename):
if self.machine.getState() != STATE_LOGGED:
self.warn("Expecting STATE_LOGGED")
return self.machine.dele(filename)
def retrieveFile(self, filename):
if self.machine.getState() != STATE_LOGGED:
self.warn("Expecting STATE_LOGGED")
suc = self.machine.pasv()
if not suc:
return None
dataSocket = self.machine.getDataSocket()
## INJECTION
# The transaction may go well (reponse code is OK) but the
# returned IP address and port may not be readable.
if not self.PASV_RESPONSE_READ_BUG:
if dataSocket is None:
self.machine.dataConnectionClearAfterError()
return None
else:
self.warn("PASV_RESPONSE_READ_BUG is active")
suc = self.dataNet.connect(dataSocket.hostname, dataSocket.port)
if not suc:
# This branch was added because of JPF, can not reproduce now.
self.machine.dataConnectionClearAfterError()
return None
dataReader = self.dataNet.createNetworkReader()
self.machine.dataConnectionEstablished()
suc = self.machine.retr(filename)
if suc:
data = dataReader.readAll()
suc2 = self.machine.transferSuccessfullyDone()
## INJECTION: the fact that transferSuccessfullyDone may fail (because it reads
# confirmation message) was discovered by JPF. Visible after two subsequent client.retrieveFile.
if not self.DATA_TRANSFER_CONFIRMATION_BUG:
if not suc2:
# transaction failed, reset the state and return null
self.machine.dataConnectionClearAfterError()
return None
else:
self.warn("DATA_TRANSFER_CONFIRMATION_BUG is active")
return data
else:
self.machine.dataConnectionClearAfterError()
return None
def retrieveFileStream(self, filename):
if self.machine.getState() != STATE_LOGGED:
self.warn("Expecting STATE_LOGGED")
suc = self.machine.pasv()
if not suc:
return None
dataSocket = self.machine.getDataSocket()
## INJECTION
# The transaction may go well (reponse code is OK) but the
# returned IP address and port may not be readable.
if not self.PASV_RESPONSE_READ_BUG:
if dataSocket is None:
self.machine.dataConnectionClearAfterError()
return None
else:
self.warn("PASV_RESPONSE_READ_BUG is active")
self.dataNet.connect(dataSocket.hostname, dataSocket.port)
dataReader = self.dataNet.createNetworkReader()
self.machine.dataConnectionEstablished()
suc = self.machine.retr(filename)
if suc:
result = FileStream(dataReader, self.machine)
result.setDATA_TRANSFER_CONFIRMATION_BUG(self.DATA_TRANSFER_CONFIRMATION_BUG)
return result;
else:
self.machine.dataConnectionClearAfterError()
return None
def __init__(self, commandNet, dataNet): self.commandNet = commandNet self.dataNet = dataNet self.machine = StateMachine(commandNet) self.DATA_TRANSFER_CONFIRMATION_BUG = False self.PASV_RESPONSE_READ_BUG = False