def __init__(self, ports, key=None, debug=False):
"""Initializes the sender object with a list of sockets containing
one socket for each port in the ports list.
Args:
ports: A list of integer port number values for the sender.
key: A base64 format string key to be used for MAC tag generation.
Default value = None.
debug: A boolean value indicating debug mode.
Raises:
TypeError: Error when key is not a string value, or when ports is not
a list of integers.
"""
try:
if type(ports) != list:
raise TypeError("invalid ports: list expected")
elif key != None and type(key) != str:
raise TypeError("invalid key: str expected")
self.host, self.ports = mysocket.gethostname(), ports
self.sock = []
self.key = key
self.debug = debug
for port in ports:
self.sock.append(mysocket())
self.sock[-1].bind((self.host, port))
print "Sender socket (%s, %d) initiated" % (self.host, port)
except:
if debug == True:
raise
else:
secureFail()
sys.exit()
def __init__(self, ports, key=None, debug=False):
"""Initializes the receiver object with a list of sockets containing
one socket for each port in the ports list.
Args:
ports: A list of integer port number values for the receiver.
key: A base64 format string key to be used for MAC tag generation.
Default value = None.
debug: A boolean value indicating debug mode.
Raises:
TypeError: Error when key is not a string value, or when ports is not
a list of integers.
"""
try:
if type(ports) != list:
raise TypeError("invalid ports: list expected")
elif key != None and type(key) != str:
raise TypeError("invalid key: str expected")
self.host, self.ports = mysocket.gethostname(), ports
self.sock = []
self.key = key
self.debug = debug
for port in ports:
self.sock.append(mysocket())
self.sock[-1].bind((self.host, port))
print "Receiver socket (%s, %d) initiated" % (self.host, port)
except:
if debug == True:
raise
else:
secureFail()
sys.exit()
def __init__(self, port, debug=False):
"""Initializes the node object with a socket object using the port
number specified by the argument port.
Args:
port: An integer port number for the node.
debug: A boolean value indicating debug mode.
Raises:
TypeError: Error when port is not an integer.
"""
try:
if type(port) not in [int, long]:
raise TypeError("invalid port: int or long expected")
self.host, self.port = mysocket.gethostname(), port
self.sock = mysocket()
self.sock.bind((self.host, self.port))
self.share = None
self.debug = debug
print "Node (%s, %d) initiated" % (self.host, self.port)
except:
if debug == True:
raise
else:
secureFail()
sys.exit()
def sendShares(self, msg, n, k, prime, nodes, mode=NO_VERIFICATION):
"""Generates n shares for the msg such that any k shares can be
used for reconstruction of the msg. According to the specified mode,
the verification information is added to each share and they are sent
to the given list of nodes. The value prime is used for as the order
of modulo operations.
Args:
msg: A string message for which the shares are to be sent.
n: An integer number representing the number of shares to be generated.
k: An integer number representing the number of shares required for
reconstruction.
prime: An integer value to be used as the order of modulo operations.
nodes: A list of (host, port) tuples for the intermediate nodes.
mode: An integer value representing the verification mode as per options
defined in the message.py module.
Returns:
A list of string value shares sent to the given nodes.
Raises:
TypeError: Error when msg is not a string, or when either n, k, prime
or mode is not an integer, or when nodes is not a list.
ValueError: Error when msg is longer than 159 characters, or when the
mode is invalid.
"""
try:
if type(msg) != str:
raise TypeError("invalid msg: str expected")
elif len(msg) > 159:
raise ValueError("invalid msg: expected 159 characters or less")
elif type(n) not in [int, long]:
raise TypeError("invalid n: int or long expected")
elif type(k) not in [int, long]:
raise TypeError("invalid k: int or long expected")
elif type(prime) not in [int, long]:
raise TypeError("invalid prime: int or long expected")
elif type(nodes) != list:
raise TypeError("invalid nodes: list expected")
elif type(mode) != type(NO_VERIFICATION):
raise TypeError("invalid mode: int or long expected")
elif mode not in [NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION]:
modeRange = "%d, %d or %d" % (NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION)
raise ValueError("invalid mode: " + modeRange + " expected")
print "Secret message:", msg
genStartTime = time()
shares = secretSharing.generateShares(msg, n, k, prime)
sharesToSend = []
if mode == NO_VERIFICATION:
sharesToSend = self.getSharesNoVrfy(shares)
elif mode == MAC_VERIFICATION:
sharesToSend = self.getSharesWithMac(shares)
elif mode == AUX_INFO_VERIFICATION:
sharesToSend = self.getSharesWithAuxInfo(shares, prime)
genEndTime = time()
for i in range(0, len(nodes)):
self.sendShareToNode(sharesToSend[i], nodes[i], i)
msgSize = sys.getsizeof(msg)
shareSize = sys.getsizeof(sharesToSend[0])
totalSharesSize = shareSize * n
print "-" * 50
print "Secret Message:", msg
print "Message Size: %d bytes" % msgSize
print "Share Size: %d bytes" % shareSize
print "Total Shares Size: %d bytes" % totalSharesSize
print "-" * 50
return [sharesToSend, genEndTime - genStartTime]
except:
if self.debug == True:
raise
else:
secureFail()
sys.exit()
dictStr = fp.read()
fp.close()
senderDict = message.strToList(dictStr)
ports = senderDict["ports"]
msg = senderDict["msg"]
n = senderDict["n"]
k = senderDict["k"]
prime = senderDict["prime"]
key = senderDict["key"]
mode = senderDict["mode"]
nodePorts = senderDict["nodes"]
addr = mysocket.gethostname()
nodes = [(addr, portNum) for portNum in nodePorts]
s = sender(ports, key, args.debug)
shares, genTime = s.sendShares(msg, n, k, prime, nodes, mode)
print "Time taken to generate shares:", genTime
print "-" * 50
except SystemExit:
pass
except:
if args.debug == True:
raise
else:
secureFail()
##################### End of Code ###########################
def reconstructSecret(self,
nodes,
buffer,
k,
t,
prime,
mode=NO_VERIFICATION):
"""Reconstruct the secret message and calculate the set of faulty nodes
based on the shares received from the nodes using the input buffer size
specified by buffer argument.
It uses the following steps:
1. Connect to each node in nodes and receive corresponding shares using the
input buffer size specified by buffer.
2. Based on the mode argument, verify the validity of each share.
3. Use k valid shares to reconstruct the secret message.
4. Use the list of invalid shares to calculate the list of faulty nodes.
Args:
nodes: A list of tuples (host, port) where host is the host name and
port is the port number of the corresponding node.
buffer: An integer value specifying the input buffer size.
k: An integer value representing the number of shares required for
reconstructing the secret message.
t: An integer value representing the maximum number of faulty nodes.
prime: An integer value specifying the prime field for modulo operations.
mode: An integer value representing the mode of verification as defined
in the module message.py
Returns:
A list containing the secret message string and a list of port numbers
of faulty nodes.
Raises:
TypeError: Error when any of k, t, prime, buffer or mode is not an
integer, or when nodes is not a list.
ValueError: Error when the mode is invalid.
"""
try:
if type(nodes) != list:
raise TypeError("invalid nodes: list expected")
elif type(buffer) not in [int, long]:
raise TypeError("invalid buffer: int or long expected")
elif type(k) not in [int, long]:
raise TypeError("invalid k: int or long expected")
elif type(t) not in [int, long]:
raise TypeError("invalid t: int or long expected")
elif type(prime) not in [int, long]:
raise TypeError("invalid prime: int or long expected")
elif type(mode) not in [int, long]:
raise TypeError("invalid mode: int or long expected")
elif mode not in [
NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION
]:
modeRange = "%d, %d or %d" % (
NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION)
raise ValueError("invalid mode: " + modeRange + " expected")
shares = self.getShares(nodes, buffer)
reconStartTime = time()
sharesForRecon = []
honestNodes = []
if mode == NO_VERIFICATION:
sharesForRecon = self.getReconSharesNoVrfy(shares, k)
elif mode == MAC_VERIFICATION:
sList, macList = self.unpackSharesMacMode(shares)
honestNodes = self.verifyMac(sList, macList)
sharesForRecon = self.getReconSharesMacMode(
sList, honestNodes, k)
elif mode == AUX_INFO_VERIFICATION:
sList, yList, bList, cList = self.unpackSharesAuxMode(shares)
honestNodes = self.verifyAuxInfo(sList, yList, bList, cList, t,
prime)
sharesForRecon = self.getReconSharesAuxMode(
sList, honestNodes, k)
print "-" * 50
print "Reconstructing Secret from Shares", sharesForRecon
secretNum = secretSharing.reconstructSecret(
sharesForRecon, k, prime)
try:
secret = message.numToStr(secretNum)
except TypeError:
secret = None
faultyNodes = self.getFaultyNodes(nodes, honestNodes)
reconEndTime = time()
return [secret, faultyNodes, reconEndTime - reconStartTime]
except:
if self.debug == True:
raise
else:
secureFail()
sys.exit()
prime = recvrDict['prime']
key = recvrDict['key']
mode = recvrDict['mode']
buf = recvrDict['buffer']
nodePorts = recvrDict['nodes']
addr = mysocket.gethostname()
nodes = [(addr, portNum) for portNum in nodePorts]
r = receiver(ports, key, args.debug)
secret, faultyNodes, reconTime = r.reconstructSecret(
nodes, buf, k, t, prime, mode)
if len(faultyNodes) == 0:
faultyNodes = None
endTime = time()
print "-" * 50
print "Reconstructed message:", secret
print "Faulty nodes:", faultyNodes
print "-" * 50
print "Time taken to reconstruct secret :", reconTime
print "-" * 50
except SystemExit:
pass
except:
if args.debug == True:
raise
else:
secureFail()
##################### End of Code ###########################
def sendShares(self, msg, n, k, prime, nodes, mode=NO_VERIFICATION):
"""Generates n shares for the msg such that any k shares can be
used for reconstruction of the msg. According to the specified mode,
the verification information is added to each share and they are sent
to the given list of nodes. The value prime is used for as the order
of modulo operations.
Args:
msg: A string message for which the shares are to be sent.
n: An integer number representing the number of shares to be generated.
k: An integer number representing the number of shares required for
reconstruction.
prime: An integer value to be used as the order of modulo operations.
nodes: A list of (host, port) tuples for the intermediate nodes.
mode: An integer value representing the verification mode as per options
defined in the message.py module.
Returns:
A list of string value shares sent to the given nodes.
Raises:
TypeError: Error when msg is not a string, or when either n, k, prime
or mode is not an integer, or when nodes is not a list.
ValueError: Error when msg is longer than 159 characters, or when the
mode is invalid.
"""
try:
if type(msg) != str:
raise TypeError("invalid msg: str expected")
elif len(msg) > 159:
raise ValueError(
"invalid msg: expected 159 characters or less")
elif type(n) not in [int, long]:
raise TypeError("invalid n: int or long expected")
elif type(k) not in [int, long]:
raise TypeError("invalid k: int or long expected")
elif type(prime) not in [int, long]:
raise TypeError("invalid prime: int or long expected")
elif type(nodes) != list:
raise TypeError("invalid nodes: list expected")
elif type(mode) != type(NO_VERIFICATION):
raise TypeError("invalid mode: int or long expected")
elif mode not in [
NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION
]:
modeRange = "%d, %d or %d" % (
NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION)
raise ValueError("invalid mode: " + modeRange + " expected")
print "Secret message:", msg
genStartTime = time()
shares = secretSharing.generateShares(msg, n, k, prime)
sharesToSend = []
if mode == NO_VERIFICATION:
sharesToSend = self.getSharesNoVrfy(shares)
elif mode == MAC_VERIFICATION:
sharesToSend = self.getSharesWithMac(shares)
elif mode == AUX_INFO_VERIFICATION:
sharesToSend = self.getSharesWithAuxInfo(shares, prime)
genEndTime = time()
for i in range(0, len(nodes)):
self.sendShareToNode(sharesToSend[i], nodes[i], i)
msgSize = sys.getsizeof(msg)
shareSize = sys.getsizeof(sharesToSend[0])
totalSharesSize = shareSize * n
print "-" * 50
print "Secret Message:", msg
print "Message Size: %d bytes" % msgSize
print "Share Size: %d bytes" % shareSize
print "Total Shares Size: %d bytes" % totalSharesSize
print "-" * 50
return [sharesToSend, genEndTime - genStartTime]
except:
if self.debug == True:
raise
else:
secureFail()
sys.exit()
def reconstructSecret(self, nodes, buffer, k, t, prime, mode=NO_VERIFICATION):
"""Reconstruct the secret message and calculate the set of faulty nodes
based on the shares received from the nodes using the input buffer size
specified by buffer argument.
It uses the following steps:
1. Connect to each node in nodes and receive corresponding shares using the
input buffer size specified by buffer.
2. Based on the mode argument, verify the validity of each share.
3. Use k valid shares to reconstruct the secret message.
4. Use the list of invalid shares to calculate the list of faulty nodes.
Args:
nodes: A list of tuples (host, port) where host is the host name and
port is the port number of the corresponding node.
buffer: An integer value specifying the input buffer size.
k: An integer value representing the number of shares required for
reconstructing the secret message.
t: An integer value representing the maximum number of faulty nodes.
prime: An integer value specifying the prime field for modulo operations.
mode: An integer value representing the mode of verification as defined
in the module message.py
Returns:
A list containing the secret message string and a list of port numbers
of faulty nodes.
Raises:
TypeError: Error when any of k, t, prime, buffer or mode is not an
integer, or when nodes is not a list.
ValueError: Error when the mode is invalid.
"""
try:
if type(nodes) != list:
raise TypeError("invalid nodes: list expected")
elif type(buffer) not in [int, long]:
raise TypeError("invalid buffer: int or long expected")
elif type(k) not in [int, long]:
raise TypeError("invalid k: int or long expected")
elif type(t) not in [int, long]:
raise TypeError("invalid t: int or long expected")
elif type(prime) not in [int, long]:
raise TypeError("invalid prime: int or long expected")
elif type(mode) not in [int, long]:
raise TypeError("invalid mode: int or long expected")
elif mode not in [NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION]:
modeRange = "%d, %d or %d" % (NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION)
raise ValueError("invalid mode: " + modeRange + " expected")
shares = self.getShares(nodes, buffer)
reconStartTime = time()
sharesForRecon = []
honestNodes = []
if mode == NO_VERIFICATION:
sharesForRecon = self.getReconSharesNoVrfy(shares, k)
elif mode == MAC_VERIFICATION:
sList, macList = self.unpackSharesMacMode(shares)
honestNodes = self.verifyMac(sList, macList)
sharesForRecon = self.getReconSharesMacMode(sList, honestNodes, k)
elif mode == AUX_INFO_VERIFICATION:
sList, yList, bList, cList = self.unpackSharesAuxMode(shares)
honestNodes = self.verifyAuxInfo(sList, yList, bList, cList, t, prime)
sharesForRecon = self.getReconSharesAuxMode(sList, honestNodes, k)
print "-" * 50
print "Reconstructing Secret from Shares", sharesForRecon
secretNum = secretSharing.reconstructSecret(sharesForRecon, k, prime)
try:
secret = message.numToStr(secretNum)
except TypeError:
secret = None
faultyNodes = self.getFaultyNodes(nodes, honestNodes)
reconEndTime = time()
return [secret, faultyNodes, reconEndTime-reconStartTime]
except:
if self.debug == True:
raise
else:
secureFail()
sys.exit()
def run(self, senderPorts, receiverPorts, buf, mode=NO_VERIFICATION, honest=True):
"""Listens to incoming connections, accepts connections from sender and
receiver nodes specified by lists of port numbers in senderPorts and
receiverPorts respectively, receives the share from the sender, manipulates
the share if it is a dishonest node (honest=False) and sends the share to
the receiver node.
If the receiver is connected before the node has received the share from the
sender, then the node waits for the share to be received before initiating
the sending of share to the receiver node.
Args:
senderPorts: A list of integer values representing port numbers used by
the sender node.
receiverPorts: A list of integer values representing port numbers used by
the receiver node.
buf: An integer value specifying the input buffer size.
mode: An integer value representing the mode of verification as defined
in the module message.py
honest: A boolean value specifying whether the node is honest or faulty.
Raises:
TypeError: Error when either buf or mode is not an integer, or when
either senderPorts or receiverPorts is not a list, or when honest
is not a boolean.
ValueError: Error when the mode is invalid.
"""
try:
if type(senderPorts) != list:
raise TypeError("invalid senderPorts: list expected")
elif type(receiverPorts) != list:
raise TypeError("invalid receiverPorts: list expected")
elif type(buf) not in [int, long]:
raise TypeError("invalid buf: int or long expected")
elif type(mode) not in [int, long]:
raise TypeError("invalid mode: int or long expected")
elif type(honest) != bool:
raise TypeError("invalid honest: bool expected")
elif mode not in [NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION]:
modeRange = "%d, %d or %d" % (NO_VERIFICATION, MAC_VERIFICATION, AUX_INFO_VERIFICATION)
raise ValueError("invalid mode: " + modeRange + " expected")
self.sock.listen(5)
clients = [None, None]
tasksDone = [False, False]
while tasksDone.count(True) != 2:
if clients.count(None) > 0:
c, addr = self.sock.accept()
port = addr[1]
if port in senderPorts:
clients[0] = c
print "Sender (Port=%d) connected" % port
elif port in receiverPorts:
clients[1] = c
print "Receiver (Port=%d) connected" % port
else:
print "Unknown node %s connected. Dropping connection!" % addr
c.close()
if clients[0] != None and tasksDone[0] != True:
self.receiveShare(clients[0], buf)
clients[0].close()
print "Share received:", self.share, "\n"
if honest == False:
self.manipulateShare(mode)
print "Share manipulated:", self.share, "\n"
tasksDone[0] = True
print "-" * 50
if clients[1] != None and tasksDone[0] == True and self.isShareReceived():
self.sendShare(clients[1])
clients[1].close()
print "Sent:", self.share, "\n"
tasksDone[1] = True
self.sock.close()
except:
if self.debug == True:
raise
else:
secureFail()
sys.exit()
