3 # Electrum - lightweight Bitcoin client
4 # Copyright (C) 2012 thomasv@ecdsa.org
6 # This program is free software: you can redistribute it and/or modify
7 # it under the terms of the GNU General Public License as published by
8 # the Free Software Foundation, either version 3 of the License, or
9 # (at your option) any later version.
11 # This program is distributed in the hope that it will be useful,
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 # GNU General Public License for more details.
16 # You should have received a copy of the GNU General Public License
17 # along with this program. If not, see <http://www.gnu.org/licenses/>.
20 import threading, time, Queue, os, sys, shutil
21 from util import user_dir, appdata_dir, print_error
27 class TxVerifier(threading.Thread):
28 """ Simple Payment Verification """
30 def __init__(self, interface, blockchain, storage):
31 threading.Thread.__init__(self)
33 self.storage = storage
34 self.blockchain = blockchain
35 self.interface = interface
36 self.transactions = {} # requested verifications (with height sent by the requestor)
37 self.interface.register_channel('txverifier')
38 self.verified_tx = storage.get('verified_tx3',{}) # height, timestamp of verified transactions
39 self.merkle_roots = storage.get('merkle_roots',{}) # hashed by me
40 self.lock = threading.Lock()
44 def get_confirmations(self, tx):
45 """ return the number of confirmations of a monitored transaction. """
47 if tx in self.verified_tx:
48 height, timestamp, pos = self.verified_tx[tx]
49 conf = (self.blockchain.local_height - height + 1)
50 if conf <= 0: timestamp = None
52 elif tx in self.transactions:
60 return conf, timestamp
63 def get_txpos(self, tx_hash):
64 "return position, even if the tx is unverified"
66 x = self.verified_tx.get(tx_hash)
67 y = self.transactions.get(tx_hash)
69 height, timestamp, pos = x
77 def get_height(self, tx_hash):
79 v = self.verified_tx.get(tx_hash)
80 height = v[0] if v else None
84 def add(self, tx_hash, tx_height):
85 """ add a transaction to the list of monitored transactions. """
88 if tx_hash not in self.transactions.keys():
89 self.transactions[tx_hash] = tx_height
92 with self.lock: self.running = False
93 self.interface.poke('verifier')
96 with self.lock: return self.running
100 while self.is_running():
103 for tx_hash, tx_height in self.transactions.items():
104 if tx_hash not in self.verified_tx:
105 if self.merkle_roots.get(tx_hash) is None and tx_hash not in requested_merkle:
106 print_error('requesting merkle', tx_hash)
107 self.interface.send([ ('blockchain.transaction.get_merkle',[tx_hash, tx_height]) ], 'txverifier')
108 requested_merkle.append(tx_hash)
111 r = self.interface.get_response('txverifier',timeout=1)
117 print_error('Verifier received an error:', r)
125 if method == 'blockchain.transaction.get_merkle':
127 self.verify_merkle(tx_hash, result)
128 requested_merkle.remove(tx_hash)
131 def verify_merkle(self, tx_hash, result):
132 tx_height = result.get('block_height')
133 pos = result.get('pos')
134 self.merkle_roots[tx_hash] = self.hash_merkle_root(result['merkle'], tx_hash, pos)
135 header = self.blockchain.read_header(tx_height)
136 if not header: return
137 assert header.get('merkle_root') == self.merkle_roots[tx_hash]
138 # we passed all the tests
139 header = self.read_header(tx_height)
140 timestamp = header.get('timestamp')
142 self.verified_tx[tx_hash] = (tx_height, timestamp, pos)
143 print_error("verified %s"%tx_hash)
144 self.storage.set_key('verified_tx3', self.verified_tx, True)
145 self.interface.trigger_callback('updated')
148 def hash_merkle_root(self, merkle_s, target_hash, pos):
149 h = hash_decode(target_hash)
150 for i in range(len(merkle_s)):
152 h = Hash( hash_decode(item) + h ) if ((pos >> i) & 1) else Hash( h + hash_decode(item) )
153 return hash_encode(h)