client/wallet.py

   1 #!/usr/bin/env python
   2 #
   3 # Electrum - lightweight Bitcoin client
   4 # Copyright (C) 2011 thomasv@gitorious
   5 #
   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.
  10 #
  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.
  15 #
  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/>.
  18
  19
  20 import sys, base64, os, re, hashlib, copy, operator, ast, threading
  21
  22 try:
  23     import ecdsa
  24     from ecdsa.util import string_to_number, number_to_string
  25 except:
  26     print "python-ecdsa does not seem to be installed. Try 'sudo easy_install ecdsa'"
  27     sys.exit(1)
  28
  29 try:
  30     import aes
  31 except:
  32     print "AES does not seem to be installed. Try 'sudo easy_install slowaes'"
  33     sys.exit(1)
  34
  35
  36 ############ functions from pywallet #####################
  37
  38 addrtype = 0
  39
  40 def hash_160(public_key):
  41     md = hashlib.new('ripemd160')
  42     md.update(hashlib.sha256(public_key).digest())
  43     return md.digest()
  44
  45 def public_key_to_bc_address(public_key):
  46     h160 = hash_160(public_key)
  47     return hash_160_to_bc_address(h160)
  48
  49 def hash_160_to_bc_address(h160):
  50     vh160 = chr(addrtype) + h160
  51     h = Hash(vh160)
  52     addr = vh160 + h[0:4]
  53     return b58encode(addr)
  54
  55 def bc_address_to_hash_160(addr):
  56     bytes = b58decode(addr, 25)
  57     return bytes[1:21]
  58
  59 __b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
  60 __b58base = len(__b58chars)
  61
  62 def b58encode(v):
  63     """ encode v, which is a string of bytes, to base58.
  64     """
  65
  66     long_value = 0L
  67     for (i, c) in enumerate(v[::-1]):
  68         long_value += (256**i) * ord(c)
  69
  70     result = ''
  71     while long_value >= __b58base:
  72         div, mod = divmod(long_value, __b58base)
  73         result = __b58chars[mod] + result
  74         long_value = div
  75     result = __b58chars[long_value] + result
  76
  77     # Bitcoin does a little leading-zero-compression:
  78     # leading 0-bytes in the input become leading-1s
  79     nPad = 0
  80     for c in v:
  81         if c == '\0': nPad += 1
  82         else: break
  83
  84     return (__b58chars[0]*nPad) + result
  85
  86 def b58decode(v, length):
  87     """ decode v into a string of len bytes
  88     """
  89     long_value = 0L
  90     for (i, c) in enumerate(v[::-1]):
  91         long_value += __b58chars.find(c) * (__b58base**i)
  92
  93     result = ''
  94     while long_value >= 256:
  95         div, mod = divmod(long_value, 256)
  96         result = chr(mod) + result
  97         long_value = div
  98     result = chr(long_value) + result
  99
 100     nPad = 0
 101     for c in v:
 102         if c == __b58chars[0]: nPad += 1
 103         else: break
 104
 105     result = chr(0)*nPad + result
 106     if length is not None and len(result) != length:
 107         return None
 108
 109     return result
 110
 111
 112 def Hash(data):
 113     return hashlib.sha256(hashlib.sha256(data).digest()).digest()
 114
 115 def EncodeBase58Check(vchIn):
 116     hash = Hash(vchIn)
 117     return b58encode(vchIn + hash[0:4])
 118
 119 def DecodeBase58Check(psz):
 120     vchRet = b58decode(psz, None)
 121     key = vchRet[0:-4]
 122     csum = vchRet[-4:]
 123     hash = Hash(key)
 124     cs32 = hash[0:4]
 125     if cs32 != csum:
 126         return None
 127     else:
 128         return key
 129
 130 def PrivKeyToSecret(privkey):
 131     return privkey[9:9+32]
 132
 133 def SecretToASecret(secret):
 134     vchIn = chr(addrtype+128) + secret
 135     return EncodeBase58Check(vchIn)
 136
 137 def ASecretToSecret(key):
 138     vch = DecodeBase58Check(key)
 139     if vch and vch[0] == chr(addrtype+128):
 140         return vch[1:]
 141     else:
 142         return False
 143
 144 ########### end pywallet functions #######################
 145
 146 # URL decode
 147 _ud = re.compile('%([0-9a-hA-H]{2})', re.MULTILINE)
 148 urldecode = lambda x: _ud.sub(lambda m: chr(int(m.group(1), 16)), x)
 149
 150
 151 def int_to_hex(i, length=1):
 152     s = hex(i)[2:].rstrip('L')
 153     s = "0"*(2*length - len(s)) + s
 154     return s.decode('hex')[::-1].encode('hex')
 155
 156
 157 # AES
 158 EncodeAES = lambda secret, s: base64.b64encode(aes.encryptData(secret,s))
 159 DecodeAES = lambda secret, e: aes.decryptData(secret, base64.b64decode(e))
 160
 161
 162
 163 # secp256k1, http://www.oid-info.com/get/1.3.132.0.10
 164 _p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2FL
 165 _r = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141L
 166 _b = 0x0000000000000000000000000000000000000000000000000000000000000007L
 167 _a = 0x0000000000000000000000000000000000000000000000000000000000000000L
 168 _Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798L
 169 _Gy = 0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8L
 170 curve_secp256k1 = ecdsa.ellipticcurve.CurveFp( _p, _a, _b )
 171 generator_secp256k1 = ecdsa.ellipticcurve.Point( curve_secp256k1, _Gx, _Gy, _r )
 172 oid_secp256k1 = (1,3,132,0,10)
 173 SECP256k1 = ecdsa.curves.Curve("SECP256k1", curve_secp256k1, generator_secp256k1, oid_secp256k1 )
 174
 175
 176 def filter(s):
 177     out = re.sub('( [^\n]*|)\n','',s)
 178     out = out.replace(' ','')
 179     out = out.replace('\n','')
 180     return out
 181
 182 def raw_tx( inputs, outputs, for_sig = None ):
 183     s  = int_to_hex(1,4)                                     +   '     version\n'
 184     s += int_to_hex( len(inputs) )                           +   '     number of inputs\n'
 185     for i in range(len(inputs)):
 186         _, _, p_hash, p_index, p_script, pubkey, sig = inputs[i]
 187         s += p_hash.decode('hex')[::-1].encode('hex')        +  '     prev hash\n'
 188         s += int_to_hex(p_index,4)                           +  '     prev index\n'
 189         if for_sig is None:
 190             sig = sig + chr(1)                               # hashtype
 191             script  = int_to_hex( len(sig))                  +  '     push %d bytes\n'%len(sig)
 192             script += sig.encode('hex')                      +  '     sig\n'
 193             pubkey = chr(4) + pubkey
 194             script += int_to_hex( len(pubkey))               +  '     push %d bytes\n'%len(pubkey)
 195             script += pubkey.encode('hex')                   +  '     pubkey\n'
 196         elif for_sig==i:
 197             script = p_script                                +  '     scriptsig \n'
 198         else:
 199             script=''
 200         s += int_to_hex( len(filter(script))/2 )             +  '     script length \n'
 201         s += script
 202         s += "ffffffff"                                      +  '     sequence\n'
 203     s += int_to_hex( len(outputs) )                          +  '     number of outputs\n'
 204     for output in outputs:
 205         addr, amount = output
 206         s += int_to_hex( amount, 8)                          +  '     amount: %d\n'%amount
 207         script = '76a9'                                      # op_dup, op_hash_160
 208         script += '14'                                       # push 0x14 bytes
 209         script += bc_address_to_hash_160(addr).encode('hex')
 210         script += '88ac'                                     # op_equalverify, op_checksig
 211         s += int_to_hex( len(filter(script))/2 )             +  '     script length \n'
 212         s += script                                          +  '     script \n'
 213     s += int_to_hex(0,4)                                     # lock time
 214     if for_sig is not None: s += int_to_hex(1, 4)            # hash type
 215     return s
 216
 217
 218
 219
 220 def format_satoshis(x, is_diff=False):
 221     from decimal import Decimal
 222     s = str( Decimal(x) /100000000 )
 223     if is_diff and x>0:
 224         s = "+" + s
 225     if not '.' in s: s += '.'
 226     p = s.find('.')
 227     s += " "*( 9 - ( len(s) - p ))
 228     s = " "*( 5 - ( p )) + s
 229     return s
 230
 231
 232 from version import ELECTRUM_VERSION, SEED_VERSION
 233
 234 DEFAULT_PORT = 50000
 235
 236
 237 class Wallet:
 238     def __init__(self):
 239
 240         self.electrum_version = ELECTRUM_VERSION
 241         self.seed_version = SEED_VERSION
 242
 243         self.gap_limit = 5           # configuration
 244         self.fee = 100000
 245         self.master_public_key = ''
 246
 247         # saved fields
 248         self.use_encryption = False
 249         self.addresses = []          # receiving addresses visible for user
 250         self.change_addresses = []   # addresses used as change
 251         self.seed = ''               # encrypted
 252         self.status = {}             # current status of addresses
 253         self.history = {}
 254         self.labels = {}             # labels for addresses and transactions
 255         self.aliases = {}            # aliases for addresses
 256         self.authorities = {}        # trusted addresses
 257
 258         self.receipts = {}           # signed URIs
 259         self.receipt = None          # next receipt
 260         self.addressbook = []        # outgoing addresses, for payments
 261
 262         # not saved
 263         self.tx_history = {}
 264
 265         self.imported_keys = {}
 266         self.remote_url = None
 267
 268         self.was_updated = False
 269         self.blocks = 0
 270         self.banner = ''
 271         self.up_to_date_event = threading.Event()
 272         self.up_to_date_event.clear()
 273
 274
 275     def set_server(self, host, port):
 276         if host!= self.host or port!=self.port:
 277             self.host = host
 278             self.port = port
 279             self.interface.is_connected = False  # this exits the polling loop
 280
 281     def set_path(self, wallet_path):
 282
 283         if wallet_path is not None:
 284             self.path = wallet_path
 285         else:
 286             # backward compatibility: look for wallet file in the default data directory
 287             if "HOME" in os.environ:
 288                 wallet_dir = os.path.join( os.environ["HOME"], '.electrum')
 289             elif "LOCALAPPDATA" in os.environ:
 290                 wallet_dir = os.path.join( os.environ["LOCALAPPDATA"], 'Electrum' )
 291             elif "APPDATA" in os.environ:
 292                 wallet_dir = os.path.join( os.environ["APPDATA"], 'Electrum' )
 293             else:
 294                 raise BaseException("No home directory found in environment variables.")
 295
 296             if not os.path.exists( wallet_dir ): os.mkdir( wallet_dir )
 297             self.path = os.path.join( wallet_dir, 'electrum.dat' )
 298
 299     def import_key(self, keypair, password):
 300         address, key = keypair.split(':')
 301         if not self.is_valid(address): return False
 302         if address in self.all_addresses(): return False
 303         b = ASecretToSecret( key )
 304         if not b: return False
 305         secexp = int( b.encode('hex'), 16)
 306         private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve=SECP256k1 )
 307         # sanity check
 308         public_key = private_key.get_verifying_key()
 309         if not address == public_key_to_bc_address( '04'.decode('hex') + public_key.to_string() ): return False
 310         self.imported_keys[address] = self.pw_encode( key, password )
 311         return True
 312
 313     def new_seed(self, password):
 314         seed = "%032x"%ecdsa.util.randrange( pow(2,128) )
 315         self.init_mpk(seed)
 316         # encrypt
 317         self.seed = self.pw_encode( seed, password )
 318
 319         # create addresses
 320         self.create_new_address_without_history(True)
 321         for i in range(self.gap_limit):
 322             self.create_new_address_without_history(False)
 323
 324
 325     def init_mpk(self,seed):
 326         # public key
 327         curve = SECP256k1
 328         secexp = self.stretch_key(seed)
 329         master_private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 330         self.master_public_key = master_private_key.get_verifying_key().to_string()
 331
 332     def all_addresses(self):
 333         return self.addresses + self.change_addresses + self.imported_keys.keys()
 334
 335     def is_mine(self, address):
 336         return address in self.all_addresses()
 337
 338     def is_change(self, address):
 339         return address in self.change_addresses
 340
 341     def is_valid(self,addr):
 342         ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
 343         if not ADDRESS_RE.match(addr): return False
 344         try:
 345             h = bc_address_to_hash_160(addr)
 346         except:
 347             return False
 348         return addr == hash_160_to_bc_address(h)
 349
 350     def stretch_key(self,seed):
 351         oldseed = seed
 352         for i in range(100000):
 353             seed = hashlib.sha256(seed + oldseed).digest()
 354         return string_to_number( seed )
 355
 356     def get_sequence(self,n,for_change):
 357         return string_to_number( Hash( "%d:%d:"%(n,for_change) + self.master_public_key ) )
 358
 359     def get_private_key(self, address, password):
 360         """  Privatekey(type,n) = Master_private_key + H(n|S|type)  """
 361         order = generator_secp256k1.order()
 362
 363         if address in self.imported_keys.keys():
 364             b = self.pw_decode( self.imported_keys[address], password )
 365             b = ASecretToSecret( b )
 366             secexp = int( b.encode('hex'), 16)
 367         else:
 368             if address in self.addresses:
 369                 n = self.addresses.index(address)
 370                 for_change = False
 371             elif address in self.change_addresses:
 372                 n = self.change_addresses.index(address)
 373                 for_change = True
 374             else:
 375                 raise BaseException("unknown address")
 376             try:
 377                 seed = self.pw_decode( self.seed, password)
 378             except:
 379                 raise BaseException("Invalid password")
 380             secexp = self.stretch_key(seed)
 381             secexp = ( secexp + self.get_sequence(n,for_change) ) % order
 382
 383         pk = number_to_string(secexp,order)
 384         return pk
 385
 386     def msg_magic(self, message):
 387         return "\x18Bitcoin Signed Message:\n" + chr( len(message) ) + message
 388
 389     def sign_message(self, address, message, password):
 390         private_key = ecdsa.SigningKey.from_string( self.get_private_key(address, password), curve = SECP256k1 )
 391         public_key = private_key.get_verifying_key()
 392         signature = private_key.sign_digest( Hash( self.msg_magic( message ) ), sigencode = ecdsa.util.sigencode_string )
 393         assert public_key.verify_digest( signature, Hash( self.msg_magic( message ) ), sigdecode = ecdsa.util.sigdecode_string)
 394         for i in range(4):
 395             sig = base64.b64encode( chr(27+i) + signature )
 396             try:
 397                 self.verify_message( address, sig, message)
 398                 return sig
 399             except:
 400                 continue
 401         else:
 402             raise BaseException("error: cannot sign message")
 403
 404
 405     def verify_message(self, address, signature, message):
 406         """ See http://www.secg.org/download/aid-780/sec1-v2.pdf for the math """
 407         from ecdsa import numbertheory, ellipticcurve, util
 408         import msqr
 409         curve = curve_secp256k1
 410         G = generator_secp256k1
 411         order = G.order()
 412         # extract r,s from signature
 413         sig = base64.b64decode(signature)
 414         if len(sig) != 65: raise BaseException("Wrong encoding")
 415         r,s = util.sigdecode_string(sig[1:], order)
 416         recid = ord(sig[0]) - 27
 417         # 1.1
 418         x = r + (recid/2) * order
 419         # 1.3
 420         alpha = ( x * x * x  + curve.a() * x + curve.b() ) % curve.p()
 421         beta = msqr.modular_sqrt(alpha, curve.p())
 422         y = beta if (beta - recid) % 2 == 0 else curve.p() - beta
 423         # 1.4 the constructor checks that nR is at infinity
 424         R = ellipticcurve.Point(curve, x, y, order)
 425         # 1.5 compute e from message:
 426         h = Hash( self.msg_magic( message ) )
 427         e = string_to_number(h)
 428         minus_e = -e % order
 429         # 1.6 compute Q = r^-1 (sR - eG)
 430         inv_r = numbertheory.inverse_mod(r,order)
 431         Q = inv_r * ( s * R + minus_e * G )
 432         public_key = ecdsa.VerifyingKey.from_public_point( Q, curve = SECP256k1 )
 433         # check that Q is the public key
 434         public_key.verify_digest( sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
 435         # check that we get the original signing address
 436         addr = public_key_to_bc_address( '04'.decode('hex') + public_key.to_string() )
 437         # print addr
 438         if address != addr:
 439             print "bad signature"
 440             raise BaseException("Bad signature")
 441
 442
 443     def create_new_address_without_history(self, for_change):
 444         """   Publickey(type,n) = Master_public_key + H(n|S|type)*point  """
 445         curve = SECP256k1
 446         n = len(self.change_addresses) if for_change else len(self.addresses)
 447         z = self.get_sequence(n,for_change)
 448         master_public_key = ecdsa.VerifyingKey.from_string( self.master_public_key, curve = SECP256k1 )
 449         pubkey_point = master_public_key.pubkey.point + z*curve.generator
 450         public_key2 = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
 451         address = public_key_to_bc_address( '04'.decode('hex') + public_key2.to_string() )
 452         if for_change:
 453             self.change_addresses.append(address)
 454         else:
 455             self.addresses.append(address)
 456
 457         self.history[address] = []
 458         self.status[address] = None
 459         print address
 460         return address
 461
 462
 463     def create_new_address(self, bool):
 464         address = self.create_new_address_without_history(bool)
 465         self.interface.subscribe([address])
 466         return address
 467
 468
 469     def synchronize(self):
 470         if not self.master_public_key:
 471             return False
 472
 473         is_new = False
 474         while True:
 475             if self.change_addresses == []:
 476                 self.create_new_address(True)
 477                 is_new = True
 478                 continue
 479             a = self.change_addresses[-1]
 480             if self.history.get(a):
 481                 self.create_new_address(True)
 482                 is_new = True
 483             else:
 484                 break
 485
 486         n = self.gap_limit
 487         while True:
 488             if len(self.addresses) < n:
 489                 self.create_new_address(False)
 490                 is_new = True
 491                 continue
 492             if map( lambda a: self.history.get(a), self.addresses[-n:] ) == n*[[]]:
 493                 break
 494             else:
 495                 self.create_new_address(False)
 496                 is_new = True
 497
 498         if self.remote_url:
 499             num = self.get_remote_number()
 500             while len(self.addresses)<num:
 501                 self.create_new_address(False)
 502                 is_new = True
 503
 504         return is_new
 505
 506
 507     def get_remote_number(self):
 508         import jsonrpclib
 509         server = jsonrpclib.Server(self.remote_url)
 510         out = server.getnum()
 511         return out
 512
 513     def get_remote_mpk(self):
 514         import jsonrpclib
 515         server = jsonrpclib.Server(self.remote_url)
 516         out = server.getkey()
 517         return out
 518
 519     def is_found(self):
 520         return (len(self.change_addresses) > 1 ) or ( len(self.addresses) > self.gap_limit )
 521
 522     def fill_addressbook(self):
 523         for tx in self.tx_history.values():
 524             if tx['value']<0:
 525                 for i in tx['outputs']:
 526                     if not self.is_mine(i) and i not in self.addressbook:
 527                         self.addressbook.append(i)
 528         # redo labels
 529         self.update_tx_labels()
 530
 531
 532     def save(self):
 533         s = {
 534             'seed_version':self.seed_version,
 535             'use_encryption':self.use_encryption,
 536             'master_public_key': self.master_public_key.encode('hex'),
 537             'fee':self.fee,
 538             'host':self.host,
 539             'port':self.port,
 540             #'blocks':self.interface.blocks,
 541             'seed':self.seed,
 542             'addresses':self.addresses,
 543             'change_addresses':self.change_addresses,
 544             'status':self.status,
 545             'history':self.history,
 546             'labels':self.labels,
 547             'contacts':self.addressbook,
 548             'imported_keys':self.imported_keys,
 549             'aliases':self.aliases,
 550             'authorities':self.authorities,
 551             'receipts':self.receipts,
 552             }
 553         f = open(self.path,"w")
 554         f.write( repr(s) )
 555         f.close()
 556
 557     def read(self):
 558         import interface
 559
 560         upgrade_msg = """This wallet seed is deprecated. Please run upgrade.py for a diagnostic."""
 561         self.file_exists = False
 562         try:
 563             f = open(self.path,"r")
 564             data = f.read()
 565             f.close()
 566         except:
 567             self.host = ''
 568             self.port = DEFAULT_PORT
 569             return
 570         try:
 571             d = ast.literal_eval( data )
 572             self.seed_version = d.get('seed_version')
 573             self.master_public_key = d.get('master_public_key').decode('hex')
 574             self.use_encryption = d.get('use_encryption')
 575             self.fee = int( d.get('fee') )
 576             self.seed = d.get('seed')
 577             self.host = d.get('host')
 578             self.port = d.get('port')
 579             blocks = d.get('blocks')
 580             self.addresses = d.get('addresses')
 581             self.change_addresses = d.get('change_addresses')
 582             self.status = d.get('status')
 583             self.history = d.get('history')
 584             self.labels = d.get('labels')
 585             self.addressbook = d.get('contacts')
 586             self.imported_keys = d.get('imported_keys',{})
 587             self.aliases = d.get('aliases',{})
 588             self.authorities = d.get('authorities',{})
 589             self.receipts = d.get('receipts',{})
 590         except:
 591             raise BaseException("cannot read wallet file")
 592
 593         self.update_tx_history()
 594
 595         if self.seed_version != SEED_VERSION:
 596             raise BaseException(upgrade_msg)
 597
 598         if self.remote_url: assert self.master_public_key.encode('hex') == self.get_remote_mpk()
 599
 600         self.file_exists = True
 601         #self.interface = interface.start_interface(self)
 602
 603
 604     def get_new_address(self):
 605         n = 0
 606         for addr in self.addresses[-self.gap_limit:]:
 607             if not self.history.get(addr):
 608                 n = n + 1
 609         if n < self.gap_limit:
 610             new_address = self.create_new_address(False)
 611             self.history[new_address] = [] #get from server
 612             return True, new_address
 613         else:
 614             return False, "The last %d addresses in your list have never been used. You should use them first, or increase the allowed gap size in your preferences. "%self.gap_limit
 615
 616     def get_addr_balance(self, addr):
 617         if self.is_mine(addr):
 618             h = self.history.get(addr)
 619         else:
 620             h = self.interface.retrieve_history(addr)
 621         if not h: return 0,0
 622         c = u = 0
 623         for item in h:
 624             v = item['value']
 625             if item['height']:
 626                 c += v
 627             else:
 628                 u += v
 629         return c, u
 630
 631     def get_balance(self):
 632         conf = unconf = 0
 633         for addr in self.all_addresses():
 634             c, u = self.get_addr_balance(addr)
 635             conf += c
 636             unconf += u
 637         return conf, unconf
 638
 639
 640     def choose_tx_inputs( self, amount, fixed_fee, from_addr = None ):
 641         """ todo: minimize tx size """
 642         total = 0
 643         fee = self.fee if fixed_fee is None else fixed_fee
 644
 645         coins = []
 646         domain = [from_addr] if from_addr else self.all_addresses()
 647         for addr in domain:
 648             h = self.history.get(addr)
 649             if h is None: continue
 650             for item in h:
 651                 if item.get('raw_scriptPubKey'):
 652                     coins.append( (addr,item))
 653
 654         coins = sorted( coins, key = lambda x: x[1]['nTime'] )
 655         inputs = []
 656         for c in coins:
 657             addr, item = c
 658             v = item.get('value')
 659             total += v
 660             inputs.append((addr, v, item['tx_hash'], item['pos'], item['raw_scriptPubKey'], None, None) )
 661             fee = self.fee*len(inputs) if fixed_fee is None else fixed_fee
 662             if total >= amount + fee: break
 663         else:
 664             #print "not enough funds: %d %d"%(total, fee)
 665             inputs = []
 666         return inputs, total, fee
 667
 668     def choose_tx_outputs( self, to_addr, amount, fee, total, change_addr=None ):
 669         outputs = [ (to_addr, amount) ]
 670         change_amount = total - ( amount + fee )
 671         if change_amount != 0:
 672             # normally, the update thread should ensure that the last change address is unused
 673             if not change_addr:
 674                 change_addr = self.change_addresses[-1]
 675             outputs.append( ( change_addr,  change_amount) )
 676         return outputs
 677
 678     def sign_inputs( self, inputs, outputs, password ):
 679         s_inputs = []
 680         for i in range(len(inputs)):
 681             addr, v, p_hash, p_pos, p_scriptPubKey, _, _ = inputs[i]
 682             private_key = ecdsa.SigningKey.from_string( self.get_private_key(addr, password), curve = SECP256k1 )
 683             public_key = private_key.get_verifying_key()
 684             pubkey = public_key.to_string()
 685             tx = filter( raw_tx( inputs, outputs, for_sig = i ) )
 686             sig = private_key.sign_digest( Hash( tx.decode('hex') ), sigencode = ecdsa.util.sigencode_der )
 687             assert public_key.verify_digest( sig, Hash( tx.decode('hex') ), sigdecode = ecdsa.util.sigdecode_der)
 688             s_inputs.append( (addr, v, p_hash, p_pos, p_scriptPubKey, pubkey, sig) )
 689         return s_inputs
 690
 691     def pw_encode(self, s, password):
 692         if password:
 693             secret = Hash(password)
 694             return EncodeAES(secret, s)
 695         else:
 696             return s
 697
 698     def pw_decode(self, s, password):
 699         if password is not None:
 700             secret = Hash(password)
 701             d = DecodeAES(secret, s)
 702             if s == self.seed:
 703                 try:
 704                     d.decode('hex')
 705                 except:
 706                     raise BaseException("Invalid password")
 707             return d
 708         else:
 709             return s
 710
 711     def receive_status_callback(self, addr, status):
 712         if self.status.get(addr) != status:
 713             #print "updating status for", addr, repr(self.status.get(addr)), repr(status)
 714             self.status[addr] = status
 715             self.interface.get_history(addr)
 716
 717     def receive_history_callback(self, addr, data):
 718         #print "updating history for", addr
 719         self.history[addr] = data
 720         self.update_tx_history()
 721         self.save()
 722
 723     def get_tx_history(self):
 724         lines = self.tx_history.values()
 725         lines = sorted(lines, key=operator.itemgetter("nTime"))
 726         return lines
 727
 728     def update_tx_history(self):
 729         self.tx_history= {}
 730         for addr in self.all_addresses():
 731             h = self.history.get(addr)
 732             if h is None: continue
 733             for tx in h:
 734                 tx_hash = tx['tx_hash']
 735                 line = self.tx_history.get(tx_hash)
 736                 if not line:
 737                     self.tx_history[tx_hash] = copy.copy(tx)
 738                     line = self.tx_history.get(tx_hash)
 739                 else:
 740                     line['value'] += tx['value']
 741                 if line['height'] == 0:
 742                     line['nTime'] = 1e12
 743         self.update_tx_labels()
 744
 745     def update_tx_labels(self):
 746         for tx in self.tx_history.values():
 747             default_label = ''
 748             if tx['value']<0:
 749                 for o_addr in tx['outputs']:
 750                     if not self.is_change(o_addr):
 751                         dest_label = self.labels.get(o_addr)
 752                         if dest_label:
 753                             default_label = 'to: ' + dest_label
 754                         else:
 755                             default_label = 'to: ' + o_addr
 756             else:
 757                 for o_addr in tx['outputs']:
 758                     if self.is_mine(o_addr) and not self.is_change(o_addr):
 759                         dest_label = self.labels.get(o_addr)
 760                         if dest_label:
 761                             default_label = 'at: ' + dest_label
 762                         else:
 763                             default_label = 'at: ' + o_addr
 764             tx['default_label'] = default_label
 765
 766     def mktx(self, to_address, amount, label, password, fee=None, change_addr=None, from_addr= None):
 767         if not self.is_valid(to_address):
 768             raise BaseException("Invalid address")
 769         inputs, total, fee = self.choose_tx_inputs( amount, fee, from_addr )
 770         if not inputs:
 771             raise BaseException("Not enough funds")
 772         outputs = self.choose_tx_outputs( to_address, amount, fee, total, change_addr )
 773         s_inputs = self.sign_inputs( inputs, outputs, password )
 774
 775         tx = filter( raw_tx( s_inputs, outputs ) )
 776         if to_address not in self.addressbook:
 777             self.addressbook.append(to_address)
 778         if label:
 779             tx_hash = Hash(tx.decode('hex') )[::-1].encode('hex')
 780             self.labels[tx_hash] = label
 781
 782         return tx
 783
 784     def sendtx(self, tx):
 785         tx_hash = Hash(tx.decode('hex') )[::-1].encode('hex')
 786         out = self.interface.send_tx(tx)
 787         if out != tx_hash:
 788             return False, "error: " + out
 789         if self.receipt:
 790             self.receipts[tx_hash] = self.receipt
 791             self.receipt = None
 792         return True, out
 793
 794
 795     def read_alias(self, alias):
 796         # this might not be the right place for this function.
 797         import urllib
 798
 799         m1 = re.match('([\w\-\.]+)@((\w[\w\-]+\.)+[\w\-]+)', alias)
 800         m2 = re.match('((\w[\w\-]+\.)+[\w\-]+)', alias)
 801         if m1:
 802             url = 'http://' + m1.group(2) + '/bitcoin.id/' + m1.group(1)
 803         elif m2:
 804             url = 'http://' + alias + '/bitcoin.id'
 805         else:
 806             return ''
 807         try:
 808             lines = urllib.urlopen(url).readlines()
 809         except:
 810             return ''
 811
 812         # line 0
 813         line = lines[0].strip().split(':')
 814         if len(line) == 1:
 815             auth_name = None
 816             target = signing_addr = line[0]
 817         else:
 818             target, auth_name, signing_addr, signature = line
 819             msg = "alias:%s:%s:%s"%(alias,target,auth_name)
 820             print msg, signature
 821             self.verify_message(signing_addr, signature, msg)
 822
 823         # other lines are signed updates
 824         for line in lines[1:]:
 825             line = line.strip()
 826             if not line: continue
 827             line = line.split(':')
 828             previous = target
 829             print repr(line)
 830             target, signature = line
 831             self.verify_message(previous, signature, "alias:%s:%s"%(alias,target))
 832
 833         if not self.is_valid(target):
 834             raise BaseException("Invalid bitcoin address")
 835
 836         return target, signing_addr, auth_name
 837
 838     def update_password(self, seed, new_password):
 839         self.use_encryption = (new_password != '')
 840         self.seed = self.pw_encode( seed, new_password)
 841         for k in self.imported_keys.keys():
 842             a = self.imported_keys[k]
 843             b = self.pw_decode(a, password)
 844             c = self.pw_encode(b, new_password)
 845             self.imported_keys[k] = c
 846         self.save()
 847
 848     def get_alias(self, alias, interactive = False, show_message=None, question = None):
 849         try:
 850             target, signing_address, auth_name = self.read_alias(alias)
 851         except BaseException, e:
 852             # raise exception if verify fails (verify the chain)
 853             if interactive:
 854                 show_message("Alias error: " + e.message)
 855             return
 856
 857         print target, signing_address, auth_name
 858
 859         if auth_name is None:
 860             a = self.aliases.get(alias)
 861             if not a:
 862                 msg = "Warning: the alias '%s' is self-signed.\nThe signing address is %s.\n\nDo you want to add this alias to your list of contacts?"%(alias,signing_address)
 863                 if interactive and question( msg ):
 864                     self.aliases[alias] = (signing_address, target)
 865                 else:
 866                     target = None
 867             else:
 868                 if signing_address != a[0]:
 869                     msg = "Warning: the key of alias '%s' has changed since your last visit! It is possible that someone is trying to do something nasty!!!\nDo you accept to change your trusted key?"%alias
 870                     if interactive and question( msg ):
 871                         self.aliases[alias] = (signing_address, target)
 872                     else:
 873                         target = None
 874         else:
 875             if signing_address not in self.authorities.keys():
 876                 msg = "The alias: '%s' links to %s\n\nWarning: this alias was signed by an unknown key.\nSigning authority: %s\nSigning address: %s\n\nDo you want to add this key to your list of trusted keys?"%(alias,target,auth_name,signing_address)
 877                 if interactive and question( msg ):
 878                     self.authorities[signing_address] = auth_name
 879                 else:
 880                     target = None
 881
 882         if target:
 883             self.aliases[alias] = (signing_address, target)
 884
 885         return target
 886
 887
 888     def parse_url(self, url, show_message, question):
 889         o = url[8:].split('?')
 890         address = o[0]
 891         if len(o)>1:
 892             params = o[1].split('&')
 893         else:
 894             params = []
 895
 896         amount = label = message = signature = identity = ''
 897         for p in params:
 898             k,v = p.split('=')
 899             uv = urldecode(v)
 900             if k == 'amount': amount = uv
 901             elif k == 'message': message = uv
 902             elif k == 'label': label = uv
 903             elif k == 'signature':
 904                 identity, signature = uv.split(':')
 905                 url = url.replace('&%s=%s'%(k,v),'')
 906             else:
 907                 print k,v
 908
 909         if signature:
 910             if re.match('^(|([\w\-\.]+)@)((\w[\w\-]+\.)+[\w\-]+)$', identity):
 911                 signing_address = self.get_alias(identity, True, show_message, question)
 912             elif self.is_valid(identity):
 913                 signing_address = identity
 914             else:
 915                 signing_address = None
 916             if not signing_address:
 917                 return
 918             try:
 919                 self.verify_message(signing_address, signature, url )
 920                 self.receipt = (signing_address, signature, url)
 921             except:
 922                 show_message('Warning: the URI contains a bad signature.\nThe identity of the recipient cannot be verified.')
 923                 address = amount = label = identity = message = ''
 924
 925         if re.match('^(|([\w\-\.]+)@)((\w[\w\-]+\.)+[\w\-]+)$', address):
 926             payto_address = self.get_alias(address, True, show_message, question)
 927             if payto_address:
 928                 address = address + ' <' + payto_address + '>'
 929
 930         return address, amount, label, message, signature, identity, url
 931
 932
 933
 934     def handle_response(self, r):
 935         if r is None:
 936             return
 937
 938         method = r['method']
 939         params = r['params']
 940         result = r['result']
 941
 942         if method == 'server.banner':
 943             self.banner = result
 944             self.was_updated = True
 945
 946         elif method == 'session.poll':
 947             # native poll
 948             blocks, changed_addresses = result
 949             if blocks == -1: raise BaseException("session not found")
 950             self.blocks = int(blocks)
 951             if changed_addresses:
 952                 self.was_updated = True
 953                 for addr, status in changed_addresses.items():
 954                     self.receive_status_callback(addr, status)
 955
 956         elif method == 'server.peers':
 957             self.interface.servers = map( lambda x:x[1], result )
 958
 959         elif method == 'address.subscribe':
 960             addr = params[-1]
 961             self.receive_status_callback(addr, result)
 962
 963         elif method == 'address.get_history':
 964             addr = params[0]
 965             self.receive_history_callback(addr, result)
 966             self.was_updated = True
 967
 968         elif method == 'transaction.broadcast':
 969             self.tx_result = result
 970             self.tx_event.set()
 971
 972         elif method == 'numblocks.subscribe':
 973             self.blocks = result
 974
 975         elif method == 'client.version':
 976             pass
 977
 978         else:
 979             print "unknown message:", method, params, result
 980
 981
 982     def update(self):
 983         self.up_to_date_event.wait()
 984
 985
 986     def run(self):
 987         while self.interface.is_connected:
 988             # the interface should use an input queue for requests so that we don't care about synchronous
 989             is_new = self.synchronize() # in synchronous mode, this puts new responses in the queue
 990             if self.interface.is_up_to_date() and not is_new:
 991                 self.up_to_date = True
 992                 self.up_to_date_event.set()
 993             else:
 994                 self.up_to_date = False
 995
 996             response = self.interface.responses.get()
 997             self.handle_response(response)
 998
 999     def start_interface(self):
1000         from interface import NativeInterface, AsynchronousInterface, HttpInterface, DEFAULT_SERVERS
1001         import random
1002
1003         if not self.host:
1004             self.host = random.choice( DEFAULT_SERVERS )         # random choice when the wallet is created
1005
1006         if self.port == 50000:
1007             InterfaceClass = NativeInterface
1008         elif self.port == 50001:
1009             InterfaceClass = AsynchronousInterface
1010         elif self.port in [80, 81, 8080, 8081]:
1011             InterfaceClass = HttpInterface
1012         else:
1013             print "unknown port number: %d. using native protocol."%self.port
1014             InterfaceClass = NativeInterface
1015
1016         self.interface = InterfaceClass(self.host, self.port)
1017         addresses = self.all_addresses()
1018         version = self.electrum_version
1019         self.interface.start_session(addresses, version)
1020         print "Starting new session: %s:%d"%(self.host,self.port)