add cosignerpool plugin

plugins/cosigner_pool.py

@@ -0,0 +1,191 @@
+#!/usr/bin/env python
+#
+# Electrum - lightweight Bitcoin client
+# Copyright (C) 2014 Thomas Voegtlin
+#
+# 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 socket
+import threading
+import time
+import xmlrpclib
+
+from PyQt4.QtGui import *
+from PyQt4.QtCore import *
+
+from electrum import bitcoin, util
+from electrum import transaction
+from electrum.plugins import BasePlugin
+from electrum.i18n import _
+
+import sys
+import traceback
+
+
+PORT = 12344
+HOST = 'ecdsa.net'
+description = _("This plugin facilitates the use of multi-signatures wallets. It sends and receives partially signed transactions from/to your cosigner wallet. Transactions are encrypted and stored on a remote server.") 
+server = xmlrpclib.ServerProxy('http://%s:%d'%(HOST,PORT), allow_none=True)
+
+
+class Listener(threading.Thread):
+
+    def __init__(self, parent):
+        threading.Thread.__init__(self)
+        self.daemon = True
+        self.parent = parent
+        self.key = None
+        self.is_running = False
+        self.message = None
+        self.delete = False
+ 
+    def set_key(self, key):
+        self.key = key
+
+    def clear(self):
+        self.delete = True
+
+    def run(self):
+        self.is_running = True
+        while self.is_running:
+
+            if not self.key:
+                time.sleep(2)
+                continue
+
+            if not self.message:
+                try:
+                    self.message = server.get(self.key)
+                except Exception as e:
+                    util.print_error("cannot contact cosigner pool")
+                    time.sleep(30)
+                    continue
+
+                if self.message:
+                    self.parent.win.emit(SIGNAL("cosigner:receive"))
+            else:
+                if self.delete:
+                    # save it to disk
+                    server.delete(self.key)
+                    self.message = None
+                    self.delete = False
+
+            time.sleep(30)
+
+
+class Plugin(BasePlugin):
+
+    wallet = None
+    listener = None
+
+    def fullname(self):
+        return 'Cosigner Pool'
+
+    def description(self):
+        return description
+
+    def init(self):
+        self.win = self.gui.main_window
+        self.win.connect(self.win, SIGNAL('cosigner:receive'), self.on_receive)
+        if self.listener is None:
+            self.listener = Listener(self)
+            self.listener.start()
+
+    def load_wallet(self, wallet):
+        self.wallet = wallet
+        mpk = self.wallet.get_master_public_keys()
+
+        self.cold = mpk.get('cold')
+        if self.cold:
+            self.cold_K = bitcoin.deserialize_xkey(self.cold)[-1].encode('hex')
+            self.cold_hash = bitcoin.Hash(self.cold_K).encode('hex')
+
+        self.hot = mpk.get('hot')
+        if self.hot:
+            self.hot_K = bitcoin.deserialize_xkey(self.hot)[-1].encode('hex')
+            self.hot_hash = bitcoin.Hash(self.hot_K).encode('hex')
+            self.listener.set_key(self.hot_hash)
+
+
+    def transaction_dialog(self, d):
+        self.send_button = b = QPushButton(_("Send to cosigner"))
+        b.clicked.connect(lambda: self.do_send(d.tx))
+        d.buttons.insertWidget(2, b)
+        self.transaction_dialog_update(d)
+
+
+    def transaction_dialog_update(self, d):
+        if d.tx.is_complete():
+            self.send_button.hide()
+            return
+        if self.cosigner_can_sign(d.tx):
+            self.send_button.show()
+        else:
+            self.send_button.hide()
+
+
+    def cosigner_can_sign(self, tx):
+        from electrum.transaction import x_to_xpub
+        xpub_set = set([])
+        for txin in tx.inputs:
+            for x_pubkey in txin['x_pubkeys']:
+                xpub = x_to_xpub(x_pubkey)
+                if xpub:
+                    xpub_set.add(xpub)
+
+        return self.cold in xpub_set
+
+
+    def do_send(self, tx):
+        if not self.cosigner_can_sign(tx):
+            return
+
+        message = bitcoin.encrypt_message(tx.raw, self.cold_K)
+
+        try:
+            server.put(self.cold_hash, message)
+            self.win.show_message("Your transaction was sent to the cosigning pool.\nOpen your cosigner wallet to retrieve it.")
+        except Exception as e:
+            self.win.show_message(str(e))
+
+
+    def on_receive(self):
+
+        if self.wallet.use_encryption:
+            password = self.win.password_dialog('An encrypted transaction was retrieved from cosigning pool.\nPlease enter your password to decrypt it.')
+            if not password:
+                return
+        else:
+            password = None
+
+        message = self.listener.message
+        xpriv = self.wallet.get_master_private_key('m/', password)
+        if not xpriv:
+            return
+        try:
+            k = bitcoin.deserialize_xkey(xpriv)[-1].encode('hex')
+            EC = bitcoin.EC_KEY(k.decode('hex'))
+            message = EC.decrypt_message(message)
+        except Exception as e:
+            traceback.print_exc(file=sys.stdout)
+            self.win.show_message(str(e))
+            return
+
+        self.listener.clear()
+
+        tx = transaction.Transaction.deserialize(message)
+        self.win.show_transaction(tx)
+
+
+