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# -*- coding: utf-8 -*-
from . import storageprotos_pb2 as storageprotos
from ..identitykeypair import IdentityKey, IdentityKeyPair
from ..ratchet.rootkey import RootKey
from ..kdf.hkdf import HKDF
from ..ecc.curve import Curve
from ..ecc.eckeypair import ECKeyPair
from ..ratchet.chainkey import ChainKey
from ..kdf.messagekeys import MessageKeys
class SessionState:
def __init__(self, session=None):
if session is None:
self.sessionStructure = storageprotos.SessionStructure()
elif session.__class__ == SessionState:
self.sessionStructure = storageprotos.SessionStructure()
self.sessionStructure.CopyFrom(session.sessionStructure)
else:
self.sessionStructure = session
def getStructure(self):
return self.sessionStructure
def getAliceBaseKey(self):
return self.sessionStructure.aliceBaseKey
def setAliceBaseKey(self, aliceBaseKey):
self.sessionStructure.aliceBaseKey = aliceBaseKey
def setSessionVersion(self, version):
self.sessionStructure.sessionVersion = version
def getSessionVersion(self):
sessionVersion = self.sessionStructure.sessionVersion
return 2 if sessionVersion == 0 else sessionVersion
def setRemoteIdentityKey(self, identityKey):
self.sessionStructure.remoteIdentityPublic = identityKey.serialize()
def setLocalIdentityKey(self, identityKey):
self.sessionStructure.localIdentityPublic = identityKey.serialize()
def getRemoteIdentityKey(self):
if self.sessionStructure.remoteIdentityPublic is None:
return None
return IdentityKey(self.sessionStructure.remoteIdentityPublic, 0)
def getLocalIdentityKey(self):
return IdentityKey(self.sessionStructure.localIdentityPublic, 0)
def getPreviousCounter(self):
return self.sessionStructure.previousCounter
def setPreviousCounter(self, previousCounter):
self.sessionStructure.previousCounter = previousCounter
def getRootKey(self):
return RootKey(HKDF.createFor(self.getSessionVersion()), self.sessionStructure.rootKey)
def setRootKey(self, rootKey):
self.sessionStructure.rootKey = rootKey.getKeyBytes()
def getSenderRatchetKey(self):
return Curve.decodePoint(bytearray(self.sessionStructure.senderChain.senderRatchetKey), 0)
def getSenderRatchetKeyPair(self):
publicKey = self.getSenderRatchetKey()
privateKey = Curve.decodePrivatePoint(self.sessionStructure.senderChain.senderRatchetKeyPrivate)
return ECKeyPair(publicKey, privateKey)
def hasReceiverChain(self, ECPublickKey_senderEphemeral):
return self.getReceiverChain(ECPublickKey_senderEphemeral) is not None
def hasSenderChain(self):
return self.sessionStructure.HasField("senderChain")
def getReceiverChain(self, ECPublickKey_senderEphemeral):
receiverChains = self.sessionStructure.receiverChains
index = 0
for receiverChain in receiverChains:
chainSenderRatchetKey = Curve.decodePoint(bytearray(receiverChain.senderRatchetKey), 0)
if chainSenderRatchetKey == ECPublickKey_senderEphemeral:
return (receiverChain, index)
index += 1
def getReceiverChainKey(self, ECPublicKey_senderEphemeral):
receiverChainAndIndex = self.getReceiverChain(ECPublicKey_senderEphemeral)
receiverChain = receiverChainAndIndex[0]
if receiverChain is None:
return None
return ChainKey(HKDF.createFor(self.getSessionVersion()),
receiverChain.chainKey.key,
receiverChain.chainKey.index)
def addReceiverChain(self, ECPublickKey_senderRatchetKey, chainKey):
senderRatchetKey = ECPublickKey_senderRatchetKey
chain = storageprotos.SessionStructure.Chain()
chain.senderRatchetKey = senderRatchetKey.serialize()
chain.chainKey.key = chainKey.getKey()
chain.chainKey.index = chainKey.getIndex()
self.sessionStructure.receiverChains.extend([chain])
if len(self.sessionStructure.receiverChains) > 5:
del self.sessionStructure.receiverChains[0]
def setSenderChain(self, ECKeyPair_senderRatchetKeyPair, chainKey):
senderRatchetKeyPair = ECKeyPair_senderRatchetKeyPair
# TODO: This is never used, maybe a bug?
senderChain = storageprotos.SessionStructure.Chain()
self.sessionStructure.senderChain.senderRatchetKey = senderRatchetKeyPair.getPublicKey().serialize()
self.sessionStructure.senderChain.senderRatchetKeyPrivate = senderRatchetKeyPair.getPrivateKey().serialize()
self.sessionStructure.senderChain.chainKey.key = chainKey.key
self.sessionStructure.senderChain.chainKey.index = chainKey.index
def getSenderChainKey(self):
chainKeyStructure = self.sessionStructure.senderChain.chainKey
return ChainKey(HKDF.createFor(self.getSessionVersion()),
chainKeyStructure.key, chainKeyStructure.index)
def setSenderChainKey(self, ChainKey_nextChainKey):
nextChainKey = ChainKey_nextChainKey
self.sessionStructure.senderChain.chainKey.key = nextChainKey.getKey()
self.sessionStructure.senderChain.chainKey.index = nextChainKey.getIndex()
def hasMessageKeys(self, ECPublickKey_senderEphemeral, counter):
senderEphemeral = ECPublickKey_senderEphemeral
chainAndIndex = self.getReceiverChain(senderEphemeral)
chain = chainAndIndex[0]
if chain is None:
return False
messageKeyList = chain.messageKeys
for messageKey in messageKeyList:
if messageKey.index == counter:
return True
return False
def removeMessageKeys(self, ECPublicKey_senderEphemeral, counter):
senderEphemeral = ECPublicKey_senderEphemeral
chainAndIndex = self.getReceiverChain(senderEphemeral)
chain = chainAndIndex[0]
if chain is None:
return None
messageKeyList = chain.messageKeys
result = None
for i in range(0, len(messageKeyList)):
messageKey = messageKeyList[i]
if messageKey.index == counter:
result = MessageKeys(messageKey.cipherKey, messageKey.macKey, messageKey.iv, messageKey.index)
del messageKeyList[i]
break
self.sessionStructure.receiverChains[chainAndIndex[1]].CopyFrom(chain)
return result
def setMessageKeys(self, ECPublicKey_senderEphemeral, messageKeys):
senderEphemeral = ECPublicKey_senderEphemeral
chainAndIndex = self.getReceiverChain(senderEphemeral)
chain = chainAndIndex[0]
messageKeyStructure = chain.messageKeys.add() # storageprotos.SessionStructure.Chain.MessageKey()
messageKeyStructure.cipherKey = messageKeys.getCipherKey()
messageKeyStructure.macKey = messageKeys.getMacKey()
messageKeyStructure.index = messageKeys.getCounter()
messageKeyStructure.iv = messageKeys.getIv()
# chain.messageKeys.append(messageKeyStructure)
self.sessionStructure.receiverChains[chainAndIndex[1]].CopyFrom(chain)
def setReceiverChainKey(self, ECPublicKey_senderEphemeral, chainKey):
senderEphemeral = ECPublicKey_senderEphemeral
chainAndIndex = self.getReceiverChain(senderEphemeral)
chain = chainAndIndex[0]
chain.chainKey.key = chainKey.getKey()
chain.chainKey.index = chainKey.getIndex()
# self.sessionStructure.receiverChains[chainAndIndex[1]].ClearField()
self.sessionStructure.receiverChains[chainAndIndex[1]].CopyFrom(chain)
def setPendingKeyExchange(self, sequence, ourBaseKey, ourRatchetKey, ourIdentityKey):
"""
:type sequence: int
:type ourBaseKey: ECKeyPair
:type ourRatchetKey: ECKeyPair
:type ourIdentityKey: IdentityKeyPair
"""
structure = self.sessionStructure.PendingKeyExchange()
structure.sequence = sequence
structure.localBaseKey = ourBaseKey.getPublicKey().serialize()
structure.localBaseKeyPrivate = ourBaseKey.getPrivateKey().serialize()
structure.localRatchetKey = ourRatchetKey.getPublicKey().serialize()
structure.localRatchetKeyPrivate = ourRatchetKey.getPrivateKey().serialize()
structure.localIdentityKey = ourIdentityKey.getPublicKey().serialize()
structure.localIdentityKeyPrivate = ourIdentityKey.getPrivateKey().serialize()
self.sessionStructure.pendingKeyExchange.MergeFrom(structure)
def getPendingKeyExchangeSequence(self):
return self.sessionStructure.pendingKeyExchange.sequence
def getPendingKeyExchangeBaseKey(self):
publicKey = Curve.decodePoint(bytearray(self.sessionStructure.pendingKeyExchange.localBaseKey), 0)
privateKey = Curve.decodePrivatePoint(self.sessionStructure.pendingKeyExchange.localBaseKeyPrivate)
return ECKeyPair(publicKey, privateKey)
def getPendingKeyExchangeRatchetKey(self):
publicKey = Curve.decodePoint(bytearray(self.sessionStructure.pendingKeyExchange.localRatchetKey), 0)
privateKey = Curve.decodePrivatePoint(self.sessionStructure.pendingKeyExchange.localRatchetKeyPrivate)
return ECKeyPair(publicKey, privateKey)
def getPendingKeyExchangeIdentityKey(self):
publicKey = IdentityKey(bytearray(self.sessionStructure.pendingKeyExchange.localIdentityKey), 0)
privateKey = Curve.decodePrivatePoint(self.sessionStructure.pendingKeyExchange.localIdentityKeyPrivate)
return IdentityKeyPair(publicKey, privateKey)
def hasPendingKeyExchange(self):
return self.sessionStructure.HasField("pendingKeyExchange")
def setUnacknowledgedPreKeyMessage(self, preKeyId, signedPreKeyId, baseKey):
"""
:type preKeyId: int
:type signedPreKeyId: int
:type baseKey: ECPublicKey
"""
self.sessionStructure.pendingPreKey.signedPreKeyId = signedPreKeyId
self.sessionStructure.pendingPreKey.baseKey = baseKey.serialize()
if preKeyId is not None:
self.sessionStructure.pendingPreKey.preKeyId = preKeyId
def hasUnacknowledgedPreKeyMessage(self):
return self.sessionStructure.HasField("pendingPreKey")
def getUnacknowledgedPreKeyMessageItems(self):
preKeyId = None
if self.sessionStructure.pendingPreKey.HasField("preKeyId"):
preKeyId = self.sessionStructure.pendingPreKey.preKeyId
return SessionState.UnacknowledgedPreKeyMessageItems(preKeyId,
self.sessionStructure.pendingPreKey.signedPreKeyId,
Curve.decodePoint(bytearray(self.sessionStructure.pendingPreKey.baseKey), 0))
def clearUnacknowledgedPreKeyMessage(self):
self.sessionStructure.ClearField("pendingPreKey")
def setRemoteRegistrationId(self, registrationId):
self.sessionStructure.remoteRegistrationId = registrationId
def getRemoteRegistrationId(self, registrationId):
return self.sessionStructure.remoteRegistrationId
def setLocalRegistrationId(self, registrationId):
self.sessionStructure.localRegistrationId = registrationId
def getLocalRegistrationId(self):
return self.sessionStructure.localRegistrationId
def serialize(self):
return self.sessionStructure.SerializeToString()
class UnacknowledgedPreKeyMessageItems:
def __init__(self, preKeyId, signedPreKeyId, baseKey):
"""
:type preKeyId: int
:type signedPreKeyId: int
:type baseKey: ECPublicKey
"""
self.preKeyId = preKeyId
self.signedPreKeyId = signedPreKeyId
self.baseKey = baseKey
def getPreKeyId(self):
return self.preKeyId
def getSignedPreKeyId(self):
return self.signedPreKeyId
def getBaseKey(self):
return self.baseKey
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