lib/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, random
  21 import aes, ecdsa
  22 from ecdsa.util import string_to_number, number_to_string
  23
  24 ############ functions from pywallet #####################
  25
  26 addrtype = 0
  27
  28 def hash_160(public_key):
  29     try:
  30         md = hashlib.new('ripemd160')
  31         md.update(hashlib.sha256(public_key).digest())
  32         return md.digest()
  33     except:
  34         import ripemd
  35         md = ripemd.new(hashlib.sha256(public_key).digest())
  36         return md.digest()
  37
  38
  39 def public_key_to_bc_address(public_key):
  40     h160 = hash_160(public_key)
  41     return hash_160_to_bc_address(h160)
  42
  43 def hash_160_to_bc_address(h160):
  44     vh160 = chr(addrtype) + h160
  45     h = Hash(vh160)
  46     addr = vh160 + h[0:4]
  47     return b58encode(addr)
  48
  49 def bc_address_to_hash_160(addr):
  50     bytes = b58decode(addr, 25)
  51     return bytes[1:21]
  52
  53 def encode_point(pubkey, compressed=False):
  54     order = generator_secp256k1.order()
  55     p = pubkey.pubkey.point
  56     x_str = ecdsa.util.number_to_string(p.x(), order)
  57     y_str = ecdsa.util.number_to_string(p.y(), order)
  58     if compressed:
  59         return chr(2 + (p.y() & 1)) + x_str
  60     else:
  61         return chr(4) + pubkey.to_string() #x_str + y_str
  62
  63 __b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
  64 __b58base = len(__b58chars)
  65
  66 def b58encode(v):
  67     """ encode v, which is a string of bytes, to base58.
  68     """
  69
  70     long_value = 0L
  71     for (i, c) in enumerate(v[::-1]):
  72         long_value += (256**i) * ord(c)
  73
  74     result = ''
  75     while long_value >= __b58base:
  76         div, mod = divmod(long_value, __b58base)
  77         result = __b58chars[mod] + result
  78         long_value = div
  79     result = __b58chars[long_value] + result
  80
  81     # Bitcoin does a little leading-zero-compression:
  82     # leading 0-bytes in the input become leading-1s
  83     nPad = 0
  84     for c in v:
  85         if c == '\0': nPad += 1
  86         else: break
  87
  88     return (__b58chars[0]*nPad) + result
  89
  90 def b58decode(v, length):
  91     """ decode v into a string of len bytes
  92     """
  93     long_value = 0L
  94     for (i, c) in enumerate(v[::-1]):
  95         long_value += __b58chars.find(c) * (__b58base**i)
  96
  97     result = ''
  98     while long_value >= 256:
  99         div, mod = divmod(long_value, 256)
 100         result = chr(mod) + result
 101         long_value = div
 102     result = chr(long_value) + result
 103
 104     nPad = 0
 105     for c in v:
 106         if c == __b58chars[0]: nPad += 1
 107         else: break
 108
 109     result = chr(0)*nPad + result
 110     if length is not None and len(result) != length:
 111         return None
 112
 113     return result
 114
 115
 116 def Hash(data):
 117     return hashlib.sha256(hashlib.sha256(data).digest()).digest()
 118
 119 def EncodeBase58Check(vchIn):
 120     hash = Hash(vchIn)
 121     return b58encode(vchIn + hash[0:4])
 122
 123 def DecodeBase58Check(psz):
 124     vchRet = b58decode(psz, None)
 125     key = vchRet[0:-4]
 126     csum = vchRet[-4:]
 127     hash = Hash(key)
 128     cs32 = hash[0:4]
 129     if cs32 != csum:
 130         return None
 131     else:
 132         return key
 133
 134 def PrivKeyToSecret(privkey):
 135     return privkey[9:9+32]
 136
 137 def SecretToASecret(secret):
 138     vchIn = chr(addrtype+128) + secret
 139     return EncodeBase58Check(vchIn)
 140
 141 def ASecretToSecret(key):
 142     vch = DecodeBase58Check(key)
 143     if vch and vch[0] == chr(addrtype+128):
 144         return vch[1:]
 145     else:
 146         return False
 147
 148 ########### end pywallet functions #######################
 149
 150 # URL decode
 151 _ud = re.compile('%([0-9a-hA-H]{2})', re.MULTILINE)
 152 urldecode = lambda x: _ud.sub(lambda m: chr(int(m.group(1), 16)), x)
 153
 154
 155 def int_to_hex(i, length=1):
 156     s = hex(i)[2:].rstrip('L')
 157     s = "0"*(2*length - len(s)) + s
 158     return s.decode('hex')[::-1].encode('hex')
 159
 160
 161 # AES
 162 EncodeAES = lambda secret, s: base64.b64encode(aes.encryptData(secret,s))
 163 DecodeAES = lambda secret, e: aes.decryptData(secret, base64.b64decode(e))
 164
 165
 166
 167 # secp256k1, http://www.oid-info.com/get/1.3.132.0.10
 168 _p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2FL
 169 _r = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141L
 170 _b = 0x0000000000000000000000000000000000000000000000000000000000000007L
 171 _a = 0x0000000000000000000000000000000000000000000000000000000000000000L
 172 _Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798L
 173 _Gy = 0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8L
 174 curve_secp256k1 = ecdsa.ellipticcurve.CurveFp( _p, _a, _b )
 175 generator_secp256k1 = ecdsa.ellipticcurve.Point( curve_secp256k1, _Gx, _Gy, _r )
 176 oid_secp256k1 = (1,3,132,0,10)
 177 SECP256k1 = ecdsa.curves.Curve("SECP256k1", curve_secp256k1, generator_secp256k1, oid_secp256k1 )
 178
 179
 180 def filter(s):
 181     out = re.sub('( [^\n]*|)\n','',s)
 182     out = out.replace(' ','')
 183     out = out.replace('\n','')
 184     return out
 185
 186 def raw_tx( inputs, outputs, for_sig = None ):
 187     s  = int_to_hex(1,4)                                     +   '     version\n'
 188     s += int_to_hex( len(inputs) )                           +   '     number of inputs\n'
 189     for i in range(len(inputs)):
 190         _, _, p_hash, p_index, p_script, pubkey, sig = inputs[i]
 191         s += p_hash.decode('hex')[::-1].encode('hex')        +  '     prev hash\n'
 192         s += int_to_hex(p_index,4)                           +  '     prev index\n'
 193         if for_sig is None:
 194             sig = sig + chr(1)                               # hashtype
 195             script  = int_to_hex( len(sig))                  +  '     push %d bytes\n'%len(sig)
 196             script += sig.encode('hex')                      +  '     sig\n'
 197             pubkey = chr(4) + pubkey
 198             script += int_to_hex( len(pubkey))               +  '     push %d bytes\n'%len(pubkey)
 199             script += pubkey.encode('hex')                   +  '     pubkey\n'
 200         elif for_sig==i:
 201             script = p_script                                +  '     scriptsig \n'
 202         else:
 203             script=''
 204         s += int_to_hex( len(filter(script))/2 )             +  '     script length \n'
 205         s += script
 206         s += "ffffffff"                                      +  '     sequence\n'
 207     s += int_to_hex( len(outputs) )                          +  '     number of outputs\n'
 208     for output in outputs:
 209         addr, amount = output
 210         s += int_to_hex( amount, 8)                          +  '     amount: %d\n'%amount
 211         script = '76a9'                                      # op_dup, op_hash_160
 212         script += '14'                                       # push 0x14 bytes
 213         script += bc_address_to_hash_160(addr).encode('hex')
 214         script += '88ac'                                     # op_equalverify, op_checksig
 215         s += int_to_hex( len(filter(script))/2 )             +  '     script length \n'
 216         s += script                                          +  '     script \n'
 217     s += int_to_hex(0,4)                                     # lock time
 218     if for_sig is not None: s += int_to_hex(1, 4)            # hash type
 219     return s
 220
 221
 222
 223
 224 def format_satoshis(x, is_diff=False, num_zeros = 0):
 225     from decimal import Decimal
 226     s = Decimal(x)
 227     sign, digits, exp = s.as_tuple()
 228     digits = map(str, digits)
 229     while len(digits) < 9:
 230         digits.insert(0,'0')
 231     digits.insert(-8,'.')
 232     s = ''.join(digits).rstrip('0')
 233     if sign:
 234         s = '-' + s
 235     elif is_diff:
 236         s = "+" + s
 237
 238     p = s.find('.')
 239     s += "0"*( 1 + num_zeros - ( len(s) - p ))
 240     s += " "*( 9 - ( len(s) - p ))
 241     s = " "*( 5 - ( p )) + s
 242     return s
 243
 244
 245 from version import ELECTRUM_VERSION, SEED_VERSION
 246 from interface import DEFAULT_SERVERS
 247
 248
 249
 250
 251 class Wallet:
 252     def __init__(self, gui_callback = lambda: None):
 253
 254         self.electrum_version = ELECTRUM_VERSION
 255         self.seed_version = SEED_VERSION
 256         self.gui_callback = gui_callback
 257
 258         self.gap_limit = 5           # configuration
 259         self.use_change = True
 260         self.fee = 100000
 261         self.num_zeros = 0
 262         self.master_public_key = ''
 263
 264         # saved fields
 265         self.use_encryption = False
 266         self.addresses = []          # receiving addresses visible for user
 267         self.change_addresses = []   # addresses used as change
 268         self.seed = ''               # encrypted
 269         self.history = {}
 270         self.labels = {}             # labels for addresses and transactions
 271         self.aliases = {}            # aliases for addresses
 272         self.authorities = {}        # trusted addresses
 273         self.frozen_addresses = []
 274         self.prioritized_addresses = []
 275         self.expert_mode = False
 276
 277         self.receipts = {}           # signed URIs
 278         self.receipt = None          # next receipt
 279         self.addressbook = []        # outgoing addresses, for payments
 280
 281         # not saved
 282         self.tx_history = {}
 283
 284         self.imported_keys = {}
 285         self.remote_url = None
 286
 287         self.was_updated = True
 288         self.blocks = -1
 289         self.banner = ''
 290
 291         # there is a difference between self.up_to_date and self.is_up_to_date()
 292         # self.is_up_to_date() returns true when all requests have been answered and processed
 293         # self.up_to_date is true when the wallet is synchronized (stronger requirement)
 294         self.up_to_date_event = threading.Event()
 295         self.up_to_date_event.clear()
 296         self.up_to_date = False
 297         self.lock = threading.Lock()
 298         self.tx_event = threading.Event()
 299
 300         self.pick_random_server()
 301
 302
 303
 304     def pick_random_server(self):
 305         self.server = random.choice( DEFAULT_SERVERS )         # random choice when the wallet is created
 306
 307     def is_up_to_date(self):
 308         return self.interface.responses.empty() and not self.interface.unanswered_requests
 309
 310     def set_server(self, server):
 311         # raise an error if the format isnt correct
 312         a,b,c = server.split(':')
 313         b = int(b)
 314         assert c in ['t','h','n']
 315         # set the server
 316         if server != self.server:
 317             self.server = server
 318             self.save()
 319             self.interface.is_connected = False  # this exits the polling loop
 320             self.interface.poke()
 321
 322     def set_path(self, wallet_path):
 323
 324         if wallet_path is not None:
 325             self.path = wallet_path
 326         else:
 327             # backward compatibility: look for wallet file in the default data directory
 328             if "HOME" in os.environ:
 329                 wallet_dir = os.path.join( os.environ["HOME"], '.electrum')
 330             elif "LOCALAPPDATA" in os.environ:
 331                 wallet_dir = os.path.join( os.environ["LOCALAPPDATA"], 'Electrum' )
 332             elif "APPDATA" in os.environ:
 333                 wallet_dir = os.path.join( os.environ["APPDATA"], 'Electrum' )
 334             else:
 335                 raise BaseException("No home directory found in environment variables.")
 336
 337             if not os.path.exists( wallet_dir ): os.mkdir( wallet_dir )
 338             self.path = os.path.join( wallet_dir, 'electrum.dat' )
 339
 340     def import_key(self, keypair, password):
 341         address, key = keypair.split(':')
 342         if not self.is_valid(address):
 343             raise BaseException('Invalid Bitcoin address')
 344         if address in self.all_addresses():
 345             raise BaseException('Address already in wallet')
 346         b = ASecretToSecret( key )
 347         if not b:
 348             raise BaseException('Unsupported key format')
 349         secexp = int( b.encode('hex'), 16)
 350         private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve=SECP256k1 )
 351         # sanity check
 352         public_key = private_key.get_verifying_key()
 353         if not address == public_key_to_bc_address( '04'.decode('hex') + public_key.to_string() ):
 354             raise BaseException('Address does not match private key')
 355         self.imported_keys[address] = self.pw_encode( key, password )
 356
 357     def new_seed(self, password):
 358         seed = "%032x"%ecdsa.util.randrange( pow(2,128) )
 359         #self.init_mpk(seed)
 360         # encrypt
 361         self.seed = self.pw_encode( seed, password )
 362
 363
 364     def init_mpk(self,seed):
 365         # public key
 366         curve = SECP256k1
 367         secexp = self.stretch_key(seed)
 368         master_private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 369         self.master_public_key = master_private_key.get_verifying_key().to_string()
 370
 371     def all_addresses(self):
 372         return self.addresses + self.change_addresses + self.imported_keys.keys()
 373
 374     def is_mine(self, address):
 375         return address in self.all_addresses()
 376
 377     def is_change(self, address):
 378         return address in self.change_addresses
 379
 380     def is_valid(self,addr):
 381         ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
 382         if not ADDRESS_RE.match(addr): return False
 383         try:
 384             h = bc_address_to_hash_160(addr)
 385         except:
 386             return False
 387         return addr == hash_160_to_bc_address(h)
 388
 389     def stretch_key(self,seed):
 390         oldseed = seed
 391         for i in range(100000):
 392             seed = hashlib.sha256(seed + oldseed).digest()
 393         return string_to_number( seed )
 394
 395     def get_sequence(self,n,for_change):
 396         return string_to_number( Hash( "%d:%d:"%(n,for_change) + self.master_public_key ) )
 397
 398     def get_private_key_base58(self, address, password):
 399         pk = self.get_private_key(address, password)
 400         if pk is None: return None
 401         return SecretToASecret( pk )
 402
 403     def get_private_key(self, address, password):
 404         """  Privatekey(type,n) = Master_private_key + H(n|S|type)  """
 405         order = generator_secp256k1.order()
 406
 407         if address in self.imported_keys.keys():
 408             b = self.pw_decode( self.imported_keys[address], password )
 409             if not b: return None
 410             b = ASecretToSecret( b )
 411             secexp = int( b.encode('hex'), 16)
 412         else:
 413             if address in self.addresses:
 414                 n = self.addresses.index(address)
 415                 for_change = False
 416             elif address in self.change_addresses:
 417                 n = self.change_addresses.index(address)
 418                 for_change = True
 419             else:
 420                 raise BaseException("unknown address")
 421             try:
 422                 seed = self.pw_decode( self.seed, password)
 423             except:
 424                 raise BaseException("Invalid password")
 425             if not seed: return None
 426             secexp = self.stretch_key(seed)
 427             secexp = ( secexp + self.get_sequence(n,for_change) ) % order
 428
 429         pk = number_to_string(secexp,order)
 430         return pk
 431
 432     def msg_magic(self, message):
 433         return "\x18Bitcoin Signed Message:\n" + chr( len(message) ) + message
 434
 435     def sign_message(self, address, message, password):
 436         private_key = ecdsa.SigningKey.from_string( self.get_private_key(address, password), curve = SECP256k1 )
 437         public_key = private_key.get_verifying_key()
 438         signature = private_key.sign_digest( Hash( self.msg_magic( message ) ), sigencode = ecdsa.util.sigencode_string )
 439         assert public_key.verify_digest( signature, Hash( self.msg_magic( message ) ), sigdecode = ecdsa.util.sigdecode_string)
 440         for i in range(4):
 441             sig = base64.b64encode( chr(27+i) + signature )
 442             try:
 443                 self.verify_message( address, sig, message)
 444                 return sig
 445             except:
 446                 continue
 447         else:
 448             raise BaseException("error: cannot sign message")
 449
 450
 451     def verify_message(self, address, signature, message):
 452         """ See http://www.secg.org/download/aid-780/sec1-v2.pdf for the math """
 453         from ecdsa import numbertheory, ellipticcurve, util
 454         import msqr
 455         curve = curve_secp256k1
 456         G = generator_secp256k1
 457         order = G.order()
 458         # extract r,s from signature
 459         sig = base64.b64decode(signature)
 460         if len(sig) != 65: raise BaseException("Wrong encoding")
 461         r,s = util.sigdecode_string(sig[1:], order)
 462         nV = ord(sig[0])
 463         if nV < 27 or nV >= 35:
 464             raise BaseException("Bad encoding")
 465         if nV >= 31:
 466             compressed = True
 467             nV -= 4
 468         else:
 469             compressed = False
 470
 471         recid = nV - 27
 472         # 1.1
 473         x = r + (recid/2) * order
 474         # 1.3
 475         alpha = ( x * x * x  + curve.a() * x + curve.b() ) % curve.p()
 476         beta = msqr.modular_sqrt(alpha, curve.p())
 477         y = beta if (beta - recid) % 2 == 0 else curve.p() - beta
 478         # 1.4 the constructor checks that nR is at infinity
 479         R = ellipticcurve.Point(curve, x, y, order)
 480         # 1.5 compute e from message:
 481         h = Hash( self.msg_magic( message ) )
 482         e = string_to_number(h)
 483         minus_e = -e % order
 484         # 1.6 compute Q = r^-1 (sR - eG)
 485         inv_r = numbertheory.inverse_mod(r,order)
 486         Q = inv_r * ( s * R + minus_e * G )
 487         public_key = ecdsa.VerifyingKey.from_public_point( Q, curve = SECP256k1 )
 488         # check that Q is the public key
 489         public_key.verify_digest( sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
 490         # check that we get the original signing address
 491         addr = public_key_to_bc_address( encode_point(public_key, compressed) )
 492         if address != addr:
 493             raise BaseException("Bad signature")
 494
 495
 496     def create_new_address(self, for_change):
 497         """   Publickey(type,n) = Master_public_key + H(n|S|type)*point  """
 498         curve = SECP256k1
 499         n = len(self.change_addresses) if for_change else len(self.addresses)
 500         z = self.get_sequence(n,for_change)
 501         master_public_key = ecdsa.VerifyingKey.from_string( self.master_public_key, curve = SECP256k1 )
 502         pubkey_point = master_public_key.pubkey.point + z*curve.generator
 503         public_key2 = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
 504         address = public_key_to_bc_address( '04'.decode('hex') + public_key2.to_string() )
 505         if for_change:
 506             self.change_addresses.append(address)
 507         else:
 508             self.addresses.append(address)
 509
 510         self.history[address] = []
 511         print address
 512         return address
 513
 514
 515     def change_gap_limit(self, value):
 516         if value >= self.gap_limit:
 517             self.gap_limit = value
 518             self.save()
 519             self.interface.poke()
 520             return True
 521
 522         elif value >= self.min_acceptable_gap():
 523             k = self.num_unused_trailing_addresses()
 524             n = len(self.addresses) - k + value
 525             self.addresses = self.addresses[0:n]
 526             self.gap_limit = value
 527             self.save()
 528             return True
 529         else:
 530             return False
 531
 532     def num_unused_trailing_addresses(self):
 533         k = 0
 534         for a in self.addresses[::-1]:
 535             if self.history.get(a):break
 536             k = k + 1
 537         return k
 538
 539     def min_acceptable_gap(self):
 540         # fixme: this assumes wallet is synchronized
 541         n = 0
 542         nmax = 0
 543         k = self.num_unused_trailing_addresses()
 544         for a in self.addresses[0:-k]:
 545             if self.history.get(a):
 546                 n = 0
 547             else:
 548                 n += 1
 549                 if n > nmax: nmax = n
 550         return nmax + 1
 551
 552
 553     def synchronize(self):
 554         if not self.master_public_key:
 555             return []
 556
 557         new_addresses = []
 558         while True:
 559             if self.change_addresses == []:
 560                 new_addresses.append( self.create_new_address(True) )
 561                 continue
 562             a = self.change_addresses[-1]
 563             if self.history.get(a):
 564                 new_addresses.append( self.create_new_address(True) )
 565             else:
 566                 break
 567
 568         n = self.gap_limit
 569         while True:
 570             if len(self.addresses) < n:
 571                 new_addresses.append( self.create_new_address(False) )
 572                 continue
 573             if map( lambda a: self.history.get(a), self.addresses[-n:] ) == n*[[]]:
 574                 break
 575             else:
 576                 new_addresses.append( self.create_new_address(False) )
 577
 578         if self.remote_url:
 579             num = self.get_remote_number()
 580             while len(self.addresses)<num:
 581                 new_addresses.append( self.create_new_address(False) )
 582
 583         return new_addresses
 584
 585
 586     def get_remote_number(self):
 587         import jsonrpclib
 588         server = jsonrpclib.Server(self.remote_url)
 589         out = server.getnum()
 590         return out
 591
 592     def get_remote_mpk(self):
 593         import jsonrpclib
 594         server = jsonrpclib.Server(self.remote_url)
 595         out = server.getkey()
 596         return out
 597
 598     def is_found(self):
 599         return (len(self.change_addresses) > 1 ) or ( len(self.addresses) > self.gap_limit )
 600
 601     def fill_addressbook(self):
 602         for tx in self.tx_history.values():
 603             if tx['value']<0:
 604                 for i in tx['outputs']:
 605                     if not self.is_mine(i) and i not in self.addressbook:
 606                         self.addressbook.append(i)
 607         # redo labels
 608         self.update_tx_labels()
 609
 610
 611     def save(self):
 612         s = {
 613             'seed_version':self.seed_version,
 614             'use_encryption':self.use_encryption,
 615             'use_change':self.use_change,
 616             'master_public_key': self.master_public_key.encode('hex'),
 617             'fee':self.fee,
 618             'server':self.server,
 619             'seed':self.seed,
 620             'addresses':self.addresses,
 621             'change_addresses':self.change_addresses,
 622             'history':self.history,
 623             'labels':self.labels,
 624             'contacts':self.addressbook,
 625             'imported_keys':self.imported_keys,
 626             'aliases':self.aliases,
 627             'authorities':self.authorities,
 628             'receipts':self.receipts,
 629             'num_zeros':self.num_zeros,
 630             'frozen_addresses':self.frozen_addresses,
 631             'prioritized_addresses':self.prioritized_addresses,
 632             'expert_mode':self.expert_mode,
 633             'gap_limit':self.gap_limit,
 634             }
 635         f = open(self.path,"w")
 636         f.write( repr(s) )
 637         f.close()
 638         import stat
 639         os.chmod(self.path,stat.S_IREAD | stat.S_IWRITE)
 640
 641     def read(self):
 642         import interface
 643
 644         upgrade_msg = """This wallet seed is deprecated. Please run upgrade.py for a diagnostic."""
 645         self.file_exists = False
 646         try:
 647             f = open(self.path,"r")
 648             data = f.read()
 649             f.close()
 650         except:
 651             return
 652         try:
 653             d = ast.literal_eval( data )
 654             interface.old_to_new(d)
 655             self.seed_version = d.get('seed_version')
 656             self.master_public_key = d.get('master_public_key').decode('hex')
 657             self.use_encryption = d.get('use_encryption')
 658             self.use_change = bool(d.get('use_change',True))
 659             self.fee = int( d.get('fee') )
 660             self.seed = d.get('seed')
 661             self.server = d.get('server')
 662             #blocks = d.get('blocks')
 663             self.addresses = d.get('addresses')
 664             self.change_addresses = d.get('change_addresses')
 665             self.history = d.get('history')
 666             self.labels = d.get('labels')
 667             self.addressbook = d.get('contacts')
 668             self.imported_keys = d.get('imported_keys',{})
 669             self.aliases = d.get('aliases',{})
 670             self.authorities = d.get('authorities',{})
 671             self.receipts = d.get('receipts',{})
 672             self.num_zeros = d.get('num_zeros',0)
 673             self.frozen_addresses = d.get('frozen_addresses',[])
 674             self.prioritized_addresses = d.get('prioritized_addresses',[])
 675             self.expert_mode = d.get('expert_mode',False)
 676             self.gap_limit = d.get('gap_limit',5)
 677         except:
 678             raise BaseException("cannot read wallet file")
 679
 680         self.update_tx_history()
 681
 682         if self.seed_version != SEED_VERSION:
 683             raise BaseException(upgrade_msg)
 684
 685         if self.remote_url: assert self.master_public_key.encode('hex') == self.get_remote_mpk()
 686
 687         self.file_exists = True
 688
 689
 690     def get_address_flags(self, addr):
 691         flags = "C" if self.is_change(addr) else "I" if addr in self.imported_keys.keys() else "-"
 692         flags += "F" if addr in self.frozen_addresses else "P" if addr in self.prioritized_addresses else "-"
 693         return flags
 694
 695
 696     def get_addr_balance(self, addr):
 697         assert self.is_mine(addr)
 698         h = self.history.get(addr,[])
 699         c = u = 0
 700         for item in h:
 701             v = item['value']
 702             if item['height']:
 703                 c += v
 704             else:
 705                 u += v
 706         return c, u
 707
 708     def get_balance(self):
 709         conf = unconf = 0
 710         for addr in self.all_addresses():
 711             c, u = self.get_addr_balance(addr)
 712             conf += c
 713             unconf += u
 714         return conf, unconf
 715
 716
 717     def choose_tx_inputs( self, amount, fixed_fee, from_addr = None ):
 718         """ todo: minimize tx size """
 719         total = 0
 720         fee = self.fee if fixed_fee is None else fixed_fee
 721
 722         coins = []
 723         prioritized_coins = []
 724         domain = [from_addr] if from_addr else self.all_addresses()
 725         for i in self.frozen_addresses:
 726             if i in domain: domain.remove(i)
 727
 728         for i in self.prioritized_addresses:
 729             if i in domain: domain.remove(i)
 730
 731         for addr in domain:
 732             h = self.history.get(addr)
 733             if h is None: continue
 734             for item in h:
 735                 if item.get('raw_output_script'):
 736                     coins.append( (addr,item))
 737
 738         coins = sorted( coins, key = lambda x: x[1]['timestamp'] )
 739
 740         for addr in self.prioritized_addresses:
 741             h = self.history.get(addr)
 742             if h is None: continue
 743             for item in h:
 744                 if item.get('raw_output_script'):
 745                     prioritized_coins.append( (addr,item))
 746
 747         prioritized_coins = sorted( prioritized_coins, key = lambda x: x[1]['timestamp'] )
 748
 749         inputs = []
 750         coins = prioritized_coins + coins
 751
 752         for c in coins:
 753             addr, item = c
 754             v = item.get('value')
 755             total += v
 756             inputs.append((addr, v, item['tx_hash'], item['index'], item['raw_output_script'], None, None) )
 757             fee = self.fee*len(inputs) if fixed_fee is None else fixed_fee
 758             if total >= amount + fee: break
 759         else:
 760             #print "not enough funds: %s %s"%(format_satoshis(total), format_satoshis(fee))
 761             inputs = []
 762         return inputs, total, fee
 763
 764     def choose_tx_outputs( self, to_addr, amount, fee, total, change_addr=None ):
 765         outputs = [ (to_addr, amount) ]
 766         change_amount = total - ( amount + fee )
 767         if change_amount != 0:
 768             # normally, the update thread should ensure that the last change address is unused
 769             if not change_addr:
 770                 change_addr = self.change_addresses[-1]
 771             outputs.append( ( change_addr,  change_amount) )
 772         return outputs
 773
 774     def sign_inputs( self, inputs, outputs, password ):
 775         s_inputs = []
 776         for i in range(len(inputs)):
 777             addr, v, p_hash, p_pos, p_scriptPubKey, _, _ = inputs[i]
 778             private_key = ecdsa.SigningKey.from_string( self.get_private_key(addr, password), curve = SECP256k1 )
 779             public_key = private_key.get_verifying_key()
 780             pubkey = public_key.to_string()
 781             tx = filter( raw_tx( inputs, outputs, for_sig = i ) )
 782             sig = private_key.sign_digest( Hash( tx.decode('hex') ), sigencode = ecdsa.util.sigencode_der )
 783             assert public_key.verify_digest( sig, Hash( tx.decode('hex') ), sigdecode = ecdsa.util.sigdecode_der)
 784             s_inputs.append( (addr, v, p_hash, p_pos, p_scriptPubKey, pubkey, sig) )
 785         return s_inputs
 786
 787     def pw_encode(self, s, password):
 788         if password:
 789             secret = Hash(password)
 790             return EncodeAES(secret, s)
 791         else:
 792             return s
 793
 794     def pw_decode(self, s, password):
 795         if password is not None:
 796             secret = Hash(password)
 797             d = DecodeAES(secret, s)
 798             if s == self.seed:
 799                 try:
 800                     d.decode('hex')
 801                 except:
 802                     raise BaseException("Invalid password")
 803             return d
 804         else:
 805             return s
 806
 807     def get_status(self, address):
 808         h = self.history.get(address)
 809         if not h:
 810             status = None
 811         else:
 812             lastpoint = h[-1]
 813             status = lastpoint['block_hash']
 814             if status == 'mempool':
 815                 status = status + ':%d'% len(h)
 816         return status
 817
 818     def receive_status_callback(self, addr, status):
 819         with self.lock:
 820             if self.get_status(addr) != status:
 821                 #print "updating status for", addr, status
 822                 self.interface.get_history(addr)
 823
 824     def receive_history_callback(self, addr, data):
 825         #print "updating history for", addr
 826         with self.lock:
 827             self.history[addr] = data
 828             self.update_tx_history()
 829             self.save()
 830
 831     def get_tx_history(self):
 832         lines = self.tx_history.values()
 833         lines = sorted(lines, key=operator.itemgetter("timestamp"))
 834         return lines
 835
 836     def update_tx_history(self):
 837         self.tx_history= {}
 838         for addr in self.all_addresses():
 839             h = self.history.get(addr)
 840             if h is None: continue
 841             for tx in h:
 842                 tx_hash = tx['tx_hash']
 843                 line = self.tx_history.get(tx_hash)
 844                 if not line:
 845                     self.tx_history[tx_hash] = copy.copy(tx)
 846                     line = self.tx_history.get(tx_hash)
 847                 else:
 848                     line['value'] += tx['value']
 849                 if line['height'] == 0:
 850                     line['timestamp'] = 1e12
 851         self.update_tx_labels()
 852
 853     def update_tx_labels(self):
 854         for tx in self.tx_history.values():
 855             default_label = ''
 856             if tx['value']<0:
 857                 for o_addr in tx['outputs']:
 858                     if not self.is_mine(o_addr):
 859                         dest_label = self.labels.get(o_addr)
 860                         if dest_label:
 861                             default_label = 'to: ' + dest_label
 862                         else:
 863                             default_label = 'to: ' + o_addr
 864             else:
 865                 for o_addr in tx['outputs']:
 866                     if self.is_mine(o_addr) and not self.is_change(o_addr):
 867                         break
 868                 else:
 869                     for o_addr in tx['outputs']:
 870                         if self.is_mine(o_addr):
 871                             break
 872                     else:
 873                         o_addr = None
 874
 875                 if o_addr:
 876                     dest_label = self.labels.get(o_addr)
 877                     if dest_label:
 878                         default_label = 'at: ' + dest_label
 879                     else:
 880                         default_label = 'at: ' + o_addr
 881
 882             tx['default_label'] = default_label
 883
 884     def mktx(self, to_address, amount, label, password, fee=None, change_addr=None, from_addr= None):
 885         if not self.is_valid(to_address):
 886             raise BaseException("Invalid address")
 887         inputs, total, fee = self.choose_tx_inputs( amount, fee, from_addr )
 888         if not inputs:
 889             raise BaseException("Not enough funds")
 890
 891         if not self.use_change and not change_addr:
 892             change_addr = inputs[0][0]
 893             print "sending change to", change_addr
 894
 895         outputs = self.choose_tx_outputs( to_address, amount, fee, total, change_addr )
 896         s_inputs = self.sign_inputs( inputs, outputs, password )
 897
 898         tx = filter( raw_tx( s_inputs, outputs ) )
 899         if to_address not in self.addressbook:
 900             self.addressbook.append(to_address)
 901         if label:
 902             tx_hash = Hash(tx.decode('hex') )[::-1].encode('hex')
 903             self.labels[tx_hash] = label
 904
 905         return tx
 906
 907     def sendtx(self, tx):
 908         tx_hash = Hash(tx.decode('hex') )[::-1].encode('hex')
 909         self.tx_event.clear()
 910         self.interface.send([('blockchain.transaction.broadcast', [tx])])
 911         self.tx_event.wait()
 912         out = self.tx_result
 913         if out != tx_hash:
 914             return False, "error: " + out
 915         if self.receipt:
 916             self.receipts[tx_hash] = self.receipt
 917             self.receipt = None
 918         return True, out
 919
 920
 921     def read_alias(self, alias):
 922         # this might not be the right place for this function.
 923         import urllib
 924
 925         m1 = re.match('([\w\-\.]+)@((\w[\w\-]+\.)+[\w\-]+)', alias)
 926         m2 = re.match('((\w[\w\-]+\.)+[\w\-]+)', alias)
 927         if m1:
 928             url = 'http://' + m1.group(2) + '/bitcoin.id/' + m1.group(1)
 929         elif m2:
 930             url = 'http://' + alias + '/bitcoin.id'
 931         else:
 932             return ''
 933         try:
 934             lines = urllib.urlopen(url).readlines()
 935         except:
 936             return ''
 937
 938         # line 0
 939         line = lines[0].strip().split(':')
 940         if len(line) == 1:
 941             auth_name = None
 942             target = signing_addr = line[0]
 943         else:
 944             target, auth_name, signing_addr, signature = line
 945             msg = "alias:%s:%s:%s"%(alias,target,auth_name)
 946             print msg, signature
 947             self.verify_message(signing_addr, signature, msg)
 948
 949         # other lines are signed updates
 950         for line in lines[1:]:
 951             line = line.strip()
 952             if not line: continue
 953             line = line.split(':')
 954             previous = target
 955             print repr(line)
 956             target, signature = line
 957             self.verify_message(previous, signature, "alias:%s:%s"%(alias,target))
 958
 959         if not self.is_valid(target):
 960             raise BaseException("Invalid bitcoin address")
 961
 962         return target, signing_addr, auth_name
 963
 964     def update_password(self, seed, old_password, new_password):
 965         if new_password == '': new_password = None
 966         self.use_encryption = (new_password != None)
 967         self.seed = self.pw_encode( seed, new_password)
 968         for k in self.imported_keys.keys():
 969             a = self.imported_keys[k]
 970             b = self.pw_decode(a, old_password)
 971             c = self.pw_encode(b, new_password)
 972             self.imported_keys[k] = c
 973         self.save()
 974
 975     def get_alias(self, alias, interactive = False, show_message=None, question = None):
 976         try:
 977             target, signing_address, auth_name = self.read_alias(alias)
 978         except BaseException, e:
 979             # raise exception if verify fails (verify the chain)
 980             if interactive:
 981                 show_message("Alias error: " + str(e))
 982             return
 983
 984         print target, signing_address, auth_name
 985
 986         if auth_name is None:
 987             a = self.aliases.get(alias)
 988             if not a:
 989                 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)
 990                 if interactive and question( msg ):
 991                     self.aliases[alias] = (signing_address, target)
 992                 else:
 993                     target = None
 994             else:
 995                 if signing_address != a[0]:
 996                     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
 997                     if interactive and question( msg ):
 998                         self.aliases[alias] = (signing_address, target)
 999                     else:
1000                         target = None
1001         else:
1002             if signing_address not in self.authorities.keys():
1003                 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)
1004                 if interactive and question( msg ):
1005                     self.authorities[signing_address] = auth_name
1006                 else:
1007                     target = None
1008
1009         if target:
1010             self.aliases[alias] = (signing_address, target)
1011
1012         return target
1013
1014
1015     def parse_url(self, url, show_message, question):
1016         o = url[8:].split('?')
1017         address = o[0]
1018         if len(o)>1:
1019             params = o[1].split('&')
1020         else:
1021             params = []
1022
1023         amount = label = message = signature = identity = ''
1024         for p in params:
1025             k,v = p.split('=')
1026             uv = urldecode(v)
1027             if k == 'amount': amount = uv
1028             elif k == 'message': message = uv
1029             elif k == 'label': label = uv
1030             elif k == 'signature':
1031                 identity, signature = uv.split(':')
1032                 url = url.replace('&%s=%s'%(k,v),'')
1033             else:
1034                 print k,v
1035
1036         if label and self.labels.get(address) != label:
1037             if question('Give label "%s" to address %s ?'%(label,address)):
1038                 if address not in self.addressbook and address not in self.all_addresses():
1039                     self.addressbook.append(address)
1040                 self.labels[address] = label
1041
1042         if signature:
1043             if re.match('^(|([\w\-\.]+)@)((\w[\w\-]+\.)+[\w\-]+)$', identity):
1044                 signing_address = self.get_alias(identity, True, show_message, question)
1045             elif self.is_valid(identity):
1046                 signing_address = identity
1047             else:
1048                 signing_address = None
1049             if not signing_address:
1050                 return
1051             try:
1052                 self.verify_message(signing_address, signature, url )
1053                 self.receipt = (signing_address, signature, url)
1054             except:
1055                 show_message('Warning: the URI contains a bad signature.\nThe identity of the recipient cannot be verified.')
1056                 address = amount = label = identity = message = ''
1057
1058         if re.match('^(|([\w\-\.]+)@)((\w[\w\-]+\.)+[\w\-]+)$', address):
1059             payto_address = self.get_alias(address, True, show_message, question)
1060             if payto_address:
1061                 address = address + ' <' + payto_address + '>'
1062
1063         return address, amount, label, message, signature, identity, url
1064
1065
1066     def update(self):
1067         self.interface.poke()
1068         self.up_to_date_event.wait(10000000000)
1069
1070
1071     def start_session(self, interface):
1072         self.interface = interface
1073         self.interface.send([('server.banner',[]), ('blockchain.numblocks.subscribe',[]), ('server.peers.subscribe',[])])
1074         self.interface.subscribe(self.all_addresses())
1075
1076
1077     def freeze(self,addr):
1078         if addr in self.all_addresses() and addr not in self.frozen_addresses:
1079             self.unprioritize(addr)
1080             self.frozen_addresses.append(addr)
1081             self.save()
1082             return True
1083         else:
1084             return False
1085
1086     def unfreeze(self,addr):
1087         if addr in self.all_addresses() and addr in self.frozen_addresses:
1088             self.frozen_addresses.remove(addr)
1089             self.save()
1090             return True
1091         else:
1092             return False
1093
1094     def prioritize(self,addr):
1095         if addr in self.all_addresses() and addr not in self.prioritized_addresses:
1096             self.unfreeze(addr)
1097             self.prioritized_addresses.append(addr)
1098             self.save()
1099             return True
1100         else:
1101             return False
1102
1103     def unprioritize(self,addr):
1104         if addr in self.all_addresses() and addr in self.prioritized_addresses:
1105             self.prioritized_addresses.remove(addr)
1106             self.save()
1107             return True
1108         else:
1109             return False