diff --git a/src/hashtree.py b/src/hashtree.py --- a/src/hashtree.py +++ b/src/hashtree.py @@ -4,60 +4,60 @@ import collections class HashTree: - HASH_LEN=16 # bytes - BLOCK_SIZE=4096 # bytes - - ## Prepares a tree containing leafCount leaves. - def __init__(self,leafCount): - self.store=[None]*(leafCount*2-1) - self.leafStart=leafCount-1 - self.index=self.leafStart - self.leafCount=leafCount - - @classmethod - def fromFile(cls,fd): - stat=os.fstat(fd.fileno()) - size=stat.st_size # !! symlinks - leafCount=(size-1)//HashTree.BLOCK_SIZE+1 # number of leaf blocks - res=cls(leafCount) - - for i in range(leafCount): - data=fd.read(HashTree.BLOCK_SIZE) - res.insertLeaf(hashlib.sha256(data).digest()[HashTree.HASH_LEN:]) - res.buildTree() - - return res - - - ## Inserts a leaf at the first empty position. - # - # Useful and used only during the tree construction. - def insertLeaf(self,h): - self.store[self.index]=h - self.index+=1 - - ## Updates a hash stored in the leaf. - def updateLeaf(self,index,h): - if index=0: - self.store[index]=hashlib.sha256(self.store[index*2+1]+self.store[index*2+2]).digest()[HashTree.HASH_LEN:] - index=(index-1)//2 - - ## Fast construction of the tree over the leaves. O(n). - def buildTree(self): - for i in range(self.leafStart-1,-1,-1): - self.store[i]=hashlib.sha256(self.store[i*2+1]+self.store[i*2+2]).digest()[HashTree.HASH_LEN:] + HASH_LEN=16 # bytes + BLOCK_SIZE=4096 # bytes + + ## Prepares a tree containing leafCount leaves. + def __init__(self,leafCount): + self.store=[None]*(leafCount*2-1) + self.leafStart=leafCount-1 + self.index=self.leafStart + self.leafCount=leafCount + + @classmethod + def fromFile(cls,fd): + stat=os.fstat(fd.fileno()) + size=stat.st_size # !! symlinks + leafCount=(size-1)//HashTree.BLOCK_SIZE+1 # number of leaf blocks + res=cls(leafCount) + + for i in range(leafCount): + data=fd.read(HashTree.BLOCK_SIZE) + res.insertLeaf(hashlib.sha256(data).digest()[HashTree.HASH_LEN:]) + res.buildTree() + + return res + + + ## Inserts a leaf at the first empty position. + # + # Useful and used only during the tree construction. + def insertLeaf(self,h): + self.store[self.index]=h + self.index+=1 + + ## Updates a hash stored in the leaf. + def updateLeaf(self,index,h): + if index=0: + self.store[index]=hashlib.sha256(self.store[index*2+1]+self.store[index*2+2]).digest()[HashTree.HASH_LEN:] + index=(index-1)//2 + + ## Fast construction of the tree over the leaves. O(n). + def buildTree(self): + for i in range(self.leafStart-1,-1,-1): + self.store[i]=hashlib.sha256(self.store[i*2+1]+self.store[i*2+2]).digest()[HashTree.HASH_LEN:] if __name__=="__main__": - f1=HashTree.fromFile(open("serverFile.txt",mode='rb')) - f2=HashTree.fromFile(open("clientFile.txt",mode='rb')) + f1=HashTree.fromFile(open("serverFile.txt",mode='rb')) + f2=HashTree.fromFile(open("clientFile.txt",mode='rb')) - for i,(h1,h2) in enumerate(zip(f1.store,f2.store)): - print("{0:2}".format(i),h1.hex(),h2.hex(),h1==h2) + for i,(h1,h2) in enumerate(zip(f1.store,f2.store)): + print("{0:2}".format(i),h1.hex(),h2.hex(),h1==h2) diff --git a/src/networkers.py b/src/networkers.py --- a/src/networkers.py +++ b/src/networkers.py @@ -4,51 +4,51 @@ import json class NetworkReader(threading.Thread): - def __init__(self,stream): - threading.Thread.__init__(self,daemon=True) - self.parent=threading.current_thread() - - self.stream=stream - self.output=queue.Queue() - - def run(self): - while True: - if not self.parent.is_alive(): return - self.output.put(self.readMsg(),timeout=2) - - def readMsg(self): - data=self.stream.readline() - if not data: pass # !! raise something - jsonLength=int(data.split(b":")[1].strip()) # "json-length: length" -> length - data=self.stream.readline() - if not data: pass # !! raise something - binLength=int(data.split(b":")[1].strip()) # "bin-length: length" -> length - jsonData=self.stream.read(jsonLength) - jsonData=json.loads(str(jsonData,encoding="utf-8")) - binData=self.stream.read(binLength) - - return (jsonData,binData) - + def __init__(self,stream): + threading.Thread.__init__(self,daemon=True) + self.parent=threading.current_thread() + + self.stream=stream + self.output=queue.Queue() + + def run(self): + while True: + if not self.parent.is_alive(): return + self.output.put(self.readMsg(),timeout=2) + + def readMsg(self): + data=self.stream.readline() + if not data: pass # !! raise something + jsonLength=int(data.split(b":")[1].strip()) # "json-length: length" -> length + data=self.stream.readline() + if not data: pass # !! raise something + binLength=int(data.split(b":")[1].strip()) # "bin-length: length" -> length + jsonData=self.stream.read(jsonLength) + jsonData=json.loads(str(jsonData,encoding="utf-8")) + binData=self.stream.read(binLength) + + return (jsonData,binData) + class NetworkWriter(threading.Thread): - def __init__(self,stream): - threading.Thread.__init__(self,daemon=True) - self.parent=threading.current_thread() - - self.stream=stream - self.input=queue.Queue() - - def run(self): - while True: - if not self.parent.is_alive(): return - msg=self.input.get(timeout=2) - if msg is None: return - self.stream.write(self.writeMsg(msg)) - self.stream.flush() - - def writeMsg(self,msg): - jsonData,binData=msg - jsonData=bytes(json.dumps(jsonData)+"\n",encoding="utf-8") - jsonLength=bytes("json-length: "+str(len(jsonData))+"\n",encoding="utf-8") - binLength=bytes("bin-length: "+str(len(binData))+"\n",encoding="utf-8") - return b"".join((jsonLength,binLength,jsonData,binData)) + def __init__(self,stream): + threading.Thread.__init__(self,daemon=True) + self.parent=threading.current_thread() + + self.stream=stream + self.input=queue.Queue() + + def run(self): + while True: + if not self.parent.is_alive(): return + msg=self.input.get(timeout=2) + if msg is None: return + self.stream.write(self.writeMsg(msg)) + self.stream.flush() + + def writeMsg(self,msg): + jsonData,binData=msg + jsonData=bytes(json.dumps(jsonData)+"\n",encoding="utf-8") + jsonLength=bytes("json-length: "+str(len(jsonData))+"\n",encoding="utf-8") + binLength=bytes("bin-length: "+str(len(binData))+"\n",encoding="utf-8") + return b"".join((jsonLength,binLength,jsonData,binData))