electrum-bitcoinprivate/lib/verifier.py

99 lines
3.4 KiB
Python

#!/usr/bin/env python
#
# Electrum - lightweight Bitcoin client
# Copyright (C) 2012 thomasv@ecdsa.org
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import threading
import Queue
import util
from bitcoin import *
class SPV(util.DaemonThread):
""" Simple Payment Verification """
def __init__(self, network, wallet):
util.DaemonThread.__init__(self)
self.wallet = wallet
self.network = network
self.merkle_roots = {} # hashed by me
self.queue = Queue.Queue()
def run(self):
requested_merkle = set()
while self.is_running():
unverified = self.wallet.get_unverified_txs()
for (tx_hash, tx_height) in unverified:
if self.merkle_roots.get(tx_hash) is None and tx_hash not in requested_merkle:
if self.network.send([ ('blockchain.transaction.get_merkle',[tx_hash, tx_height]) ], self.queue.put):
self.print_error('requesting merkle', tx_hash)
requested_merkle.add(tx_hash)
try:
r = self.queue.get(timeout=0.1)
except Queue.Empty:
continue
if not r:
continue
if r.get('error'):
self.print_error('Verifier received an error:', r)
continue
# 3. handle response
method = r['method']
params = r['params']
result = r['result']
if method == 'blockchain.transaction.get_merkle':
tx_hash = params[0]
self.verify_merkle(tx_hash, result)
self.print_error("stopped")
def verify_merkle(self, tx_hash, result):
tx_height = result.get('block_height')
pos = result.get('pos')
merkle_root = self.hash_merkle_root(result['merkle'], tx_hash, pos)
header = self.network.get_header(tx_height)
if not header: return
if header.get('merkle_root') != merkle_root:
self.print_error("merkle verification failed for", tx_hash)
return
# we passed all the tests
self.merkle_roots[tx_hash] = merkle_root
self.print_error("verified %s" % tx_hash)
self.wallet.add_verified_tx(tx_hash, (tx_height, header.get('timestamp'), pos))
def hash_merkle_root(self, merkle_s, target_hash, pos):
h = hash_decode(target_hash)
for i in range(len(merkle_s)):
item = merkle_s[i]
h = Hash( hash_decode(item) + h ) if ((pos >> i) & 1) else Hash( h + hash_decode(item) )
return hash_encode(h)
def undo_verifications(self, height):
tx_hashes = selt.wallet.undo_verifications(height)
for tx_hash in tx_hashes:
self.print_error("redoing", tx_hash)
self.merkle_roots.pop(tx_hash, None)