def generateNextBlock(blockData, pubKey, previousBlock, gwPvtKey, consensus):
""" Receive the information of a new block and create it\n
@param blockData - information of the new block\n
@param pubKey - public key of the device how wants to generate the new block\n
@param previouBlock - BlockHeader object with the last block on the chain\n
@param gwPvtKey - private key of the gateway\n
@param consensus - it is specified current consensus adopted
@return BlockHeader - the new block
"""
nextIndex = previousBlock.index + 1
nextTimestamp = time.time()
previousBlockHash = criptoFunctions.calculateHashForBlock(previousBlock)
nonce = 0
nextHash = criptoFunctions.calculateHash(nextIndex, previousBlockHash,
nextTimestamp, pubKey, nonce)
if (consensus == 'PoW'):
difficulty_bits = 12 #2 bytes or 4 hex or 16 bits of zeros in the left of hash
target = 2**(
256 - difficulty_bits
) #resulting value is lower when it has more 0 in the left of hash
while ((long(nextHash, 16) > target) and (nonce < (2**32))
): #convert hash to long to verify when it achieve difficulty
nonce = nonce + 1
nextHash = criptoFunctions.calculateHash(nextIndex,
previousBlockHash,
nextTimestamp, pubKey,
nonce)
print("####nonce = " + str(nonce))
sign = criptoFunctions.signInfo(gwPvtKey, nextHash)
inf = Transaction.Transaction(0, nextHash, nextTimestamp, blockData, sign)
return BlockHeader.BlockHeader(nextIndex, previousBlockHash, nextTimestamp,
inf, nextHash, nonce, pubKey)
def verifyBlockCandidate(newBlock, generatorGwPub, generatorDevicePub,
alivePeers):
blockValidation = True
lastBlk = chainFunctions.getLatestBlock()
# print("Index:"+str(lastBlk.index)+" prevHash:"+str(lastBlk.previousHash)+ " time:"+str(lastBlk.timestamp)+ " pubKey:")
lastBlkHash = criptoFunctions.calculateHash(lastBlk.index,
lastBlk.previousHash,
lastBlk.timestamp,
lastBlk.publicKey)
# print ("This Hash:"+str(lastBlkHash))
# print ("Last Hash:"+str(block.previousHash))
if (lastBlkHash != newBlock.previousHash):
blockValidation = False
return blockValidation
if (lastBlk.index != (newBlock.index + 1)):
blockValidation = False
return blockValidation
if (lastBlk.timestamp >= newBlock.timestamp):
blockValidation = False
return blockValidation
#TODO -> verifySIGNATURE!!!!!
if blockValidation:
voterSign = criptoFunctions.signInfo(gwPvt, newBlock)
addVoteBlockPBFT(newBlock, gwPub, voterSign) #adiciona o seu p
for p in alivePeers:
p.object.addVoteBlockPBFT(
newBlock, gwPub,
voterSign) #altera a lista de confirmacao de todos os peers
return True
else:
return False
def generateNextBlock(blockData, pubKey, previousBlock, gwPvtKey):
nextIndex = previousBlock.index + 1
nextTimestamp = time.time()
nextHash = criptoFunctions.calculateHash(nextIndex, previousBlock.hash,
nextTimestamp, pubKey)
sign = criptoFunctions.signInfo(gwPvtKey, nextHash)
inf = Transaction.Transaction(0, nextHash, nextTimestamp, blockData, sign)
return BlockHeader.BlockHeader(nextIndex, previousBlock.hash,
nextTimestamp, inf, nextHash, pubKey)
def isBlockValid(block):
#Todo Fix the comparison between the hashes... for now is just a mater to simulate the time spend calculating the hashes...
#global BlockHeaderChain
#print(str(len(BlockHeaderChain)))
lastBlk = chainFunctions.getLatestBlock()
#print("Index:"+str(lastBlk.index)+" prevHash:"+str(lastBlk.previousHash)+ " time:"+str(lastBlk.timestamp)+ " pubKey:")
lastBlkHash = criptoFunctions.calculateHash(lastBlk.index,
lastBlk.previousHash,
lastBlk.timestamp,
lastBlk.publicKey)
#print ("This Hash:"+str(lastBlkHash))
#print ("Last Hash:"+str(block.previousHash))
if (lastBlkHash == block.previousHash):
return True
else:
return True
def generateNextBlock(blockData, pubKey, previousBlock, gwPvtKey, **kwargs):
""" Receive the information of a new block and create it\n
@param blockData - information of the new block\n
@param pubKey - public key of the device how wants to generate the new block\n
@param previouBlock - BlockHeader object with the last block on the chain\n
@param gwPvtKey - private key of the gateway\n
@return BlockHeader - the new block
"""
nextIndex = previousBlock.index + 1
nextTimestamp = time.time()
#nextHash = criptoFunctions.calculateHash(nextIndex, previousBlock.hash, nextTimestamp, pubKey);
previousBlockHash = criptoFunctions.calculateHashForBlock(previousBlock)
nextHash = criptoFunctions.calculateHash(nextIndex, previousBlockHash, nextTimestamp, pubKey)
sign = criptoFunctions.signInfo(gwPvtKey, nextHash)
inf = Transaction.Transaction(0, nextHash, nextTimestamp, blockData, sign)
blockType = kwargs.get('type', None)
if (blockType):
return BlockHeader.BlockHeader(nextIndex, previousBlockHash, nextTimestamp, inf, nextHash, pubKey, type=blockType)
else:
return BlockHeader.BlockHeader(nextIndex, previousBlockHash, nextTimestamp, inf, nextHash, pubKey)