lib/transaction.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 # Note: The deserialization code originally comes from ABE.
  21
  22
  23 import bitcoin
  24 from bitcoin import *
  25 from util import print_error
  26 import time
  27 import struct
  28
  29 #
  30 # Workalike python implementation of Bitcoin's CDataStream class.
  31 #
  32 import struct
  33 import StringIO
  34 import mmap
  35
  36 NO_SIGNATURE = 'ff'
  37
  38 class SerializationError(Exception):
  39     """ Thrown when there's a problem deserializing or serializing """
  40
  41 class BCDataStream(object):
  42     def __init__(self):
  43         self.input = None
  44         self.read_cursor = 0
  45
  46     def clear(self):
  47         self.input = None
  48         self.read_cursor = 0
  49
  50     def write(self, bytes):  # Initialize with string of bytes
  51         if self.input is None:
  52             self.input = bytes
  53         else:
  54             self.input += bytes
  55
  56     def map_file(self, file, start):  # Initialize with bytes from file
  57         self.input = mmap.mmap(file.fileno(), 0, access=mmap.ACCESS_READ)
  58         self.read_cursor = start
  59
  60     def seek_file(self, position):
  61         self.read_cursor = position
  62
  63     def close_file(self):
  64         self.input.close()
  65
  66     def read_string(self):
  67         # Strings are encoded depending on length:
  68         # 0 to 252 :  1-byte-length followed by bytes (if any)
  69         # 253 to 65,535 : byte'253' 2-byte-length followed by bytes
  70         # 65,536 to 4,294,967,295 : byte '254' 4-byte-length followed by bytes
  71         # ... and the Bitcoin client is coded to understand:
  72         # greater than 4,294,967,295 : byte '255' 8-byte-length followed by bytes of string
  73         # ... but I don't think it actually handles any strings that big.
  74         if self.input is None:
  75             raise SerializationError("call write(bytes) before trying to deserialize")
  76
  77         try:
  78             length = self.read_compact_size()
  79         except IndexError:
  80             raise SerializationError("attempt to read past end of buffer")
  81
  82         return self.read_bytes(length)
  83
  84     def write_string(self, string):
  85         # Length-encoded as with read-string
  86         self.write_compact_size(len(string))
  87         self.write(string)
  88
  89     def read_bytes(self, length):
  90         try:
  91             result = self.input[self.read_cursor:self.read_cursor+length]
  92             self.read_cursor += length
  93             return result
  94         except IndexError:
  95             raise SerializationError("attempt to read past end of buffer")
  96
  97         return ''
  98
  99     def read_boolean(self): return self.read_bytes(1)[0] != chr(0)
 100     def read_int16(self): return self._read_num('<h')
 101     def read_uint16(self): return self._read_num('<H')
 102     def read_int32(self): return self._read_num('<i')
 103     def read_uint32(self): return self._read_num('<I')
 104     def read_int64(self): return self._read_num('<q')
 105     def read_uint64(self): return self._read_num('<Q')
 106
 107     def write_boolean(self, val): return self.write(chr(1) if val else chr(0))
 108     def write_int16(self, val): return self._write_num('<h', val)
 109     def write_uint16(self, val): return self._write_num('<H', val)
 110     def write_int32(self, val): return self._write_num('<i', val)
 111     def write_uint32(self, val): return self._write_num('<I', val)
 112     def write_int64(self, val): return self._write_num('<q', val)
 113     def write_uint64(self, val): return self._write_num('<Q', val)
 114
 115     def read_compact_size(self):
 116         size = ord(self.input[self.read_cursor])
 117         self.read_cursor += 1
 118         if size == 253:
 119             size = self._read_num('<H')
 120         elif size == 254:
 121             size = self._read_num('<I')
 122         elif size == 255:
 123             size = self._read_num('<Q')
 124         return size
 125
 126     def write_compact_size(self, size):
 127         if size < 0:
 128             raise SerializationError("attempt to write size < 0")
 129         elif size < 253:
 130             self.write(chr(size))
 131         elif size < 2**16:
 132             self.write('\xfd')
 133             self._write_num('<H', size)
 134         elif size < 2**32:
 135             self.write('\xfe')
 136             self._write_num('<I', size)
 137         elif size < 2**64:
 138             self.write('\xff')
 139             self._write_num('<Q', size)
 140
 141     def _read_num(self, format):
 142         (i,) = struct.unpack_from(format, self.input, self.read_cursor)
 143         self.read_cursor += struct.calcsize(format)
 144         return i
 145
 146     def _write_num(self, format, num):
 147         s = struct.pack(format, num)
 148         self.write(s)
 149
 150 #
 151 # enum-like type
 152 # From the Python Cookbook, downloaded from http://code.activestate.com/recipes/67107/
 153 #
 154 import types, string, exceptions
 155
 156 class EnumException(exceptions.Exception):
 157     pass
 158
 159 class Enumeration:
 160     def __init__(self, name, enumList):
 161         self.__doc__ = name
 162         lookup = { }
 163         reverseLookup = { }
 164         i = 0
 165         uniqueNames = [ ]
 166         uniqueValues = [ ]
 167         for x in enumList:
 168             if type(x) == types.TupleType:
 169                 x, i = x
 170             if type(x) != types.StringType:
 171                 raise EnumException, "enum name is not a string: " + x
 172             if type(i) != types.IntType:
 173                 raise EnumException, "enum value is not an integer: " + i
 174             if x in uniqueNames:
 175                 raise EnumException, "enum name is not unique: " + x
 176             if i in uniqueValues:
 177                 raise EnumException, "enum value is not unique for " + x
 178             uniqueNames.append(x)
 179             uniqueValues.append(i)
 180             lookup[x] = i
 181             reverseLookup[i] = x
 182             i = i + 1
 183         self.lookup = lookup
 184         self.reverseLookup = reverseLookup
 185     def __getattr__(self, attr):
 186         if not self.lookup.has_key(attr):
 187             raise AttributeError
 188         return self.lookup[attr]
 189     def whatis(self, value):
 190         return self.reverseLookup[value]
 191
 192
 193 # This function comes from bitcointools, bct-LICENSE.txt.
 194 def long_hex(bytes):
 195     return bytes.encode('hex_codec')
 196
 197 # This function comes from bitcointools, bct-LICENSE.txt.
 198 def short_hex(bytes):
 199     t = bytes.encode('hex_codec')
 200     if len(t) < 11:
 201         return t
 202     return t[0:4]+"..."+t[-4:]
 203
 204
 205
 206
 207 def parse_redeemScript(bytes):
 208     dec = [ x for x in script_GetOp(bytes.decode('hex')) ]
 209
 210     # 2 of 2
 211     match = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_2, opcodes.OP_CHECKMULTISIG ]
 212     if match_decoded(dec, match):
 213         pubkeys = [ dec[1][1].encode('hex'), dec[2][1].encode('hex') ]
 214         return 2, pubkeys
 215
 216     # 2 of 3
 217     match = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_3, opcodes.OP_CHECKMULTISIG ]
 218     if match_decoded(dec, match):
 219         pubkeys = [ dec[1][1].encode('hex'), dec[2][1].encode('hex'), dec[3][1].encode('hex') ]
 220         return 2, pubkeys
 221
 222
 223
 224 opcodes = Enumeration("Opcodes", [
 225     ("OP_0", 0), ("OP_PUSHDATA1",76), "OP_PUSHDATA2", "OP_PUSHDATA4", "OP_1NEGATE", "OP_RESERVED",
 226     "OP_1", "OP_2", "OP_3", "OP_4", "OP_5", "OP_6", "OP_7",
 227     "OP_8", "OP_9", "OP_10", "OP_11", "OP_12", "OP_13", "OP_14", "OP_15", "OP_16",
 228     "OP_NOP", "OP_VER", "OP_IF", "OP_NOTIF", "OP_VERIF", "OP_VERNOTIF", "OP_ELSE", "OP_ENDIF", "OP_VERIFY",
 229     "OP_RETURN", "OP_TOALTSTACK", "OP_FROMALTSTACK", "OP_2DROP", "OP_2DUP", "OP_3DUP", "OP_2OVER", "OP_2ROT", "OP_2SWAP",
 230     "OP_IFDUP", "OP_DEPTH", "OP_DROP", "OP_DUP", "OP_NIP", "OP_OVER", "OP_PICK", "OP_ROLL", "OP_ROT",
 231     "OP_SWAP", "OP_TUCK", "OP_CAT", "OP_SUBSTR", "OP_LEFT", "OP_RIGHT", "OP_SIZE", "OP_INVERT", "OP_AND",
 232     "OP_OR", "OP_XOR", "OP_EQUAL", "OP_EQUALVERIFY", "OP_RESERVED1", "OP_RESERVED2", "OP_1ADD", "OP_1SUB", "OP_2MUL",
 233     "OP_2DIV", "OP_NEGATE", "OP_ABS", "OP_NOT", "OP_0NOTEQUAL", "OP_ADD", "OP_SUB", "OP_MUL", "OP_DIV",
 234     "OP_MOD", "OP_LSHIFT", "OP_RSHIFT", "OP_BOOLAND", "OP_BOOLOR",
 235     "OP_NUMEQUAL", "OP_NUMEQUALVERIFY", "OP_NUMNOTEQUAL", "OP_LESSTHAN",
 236     "OP_GREATERTHAN", "OP_LESSTHANOREQUAL", "OP_GREATERTHANOREQUAL", "OP_MIN", "OP_MAX",
 237     "OP_WITHIN", "OP_RIPEMD160", "OP_SHA1", "OP_SHA256", "OP_HASH160",
 238     "OP_HASH256", "OP_CODESEPARATOR", "OP_CHECKSIG", "OP_CHECKSIGVERIFY", "OP_CHECKMULTISIG",
 239     "OP_CHECKMULTISIGVERIFY",
 240     ("OP_SINGLEBYTE_END", 0xF0),
 241     ("OP_DOUBLEBYTE_BEGIN", 0xF000),
 242     "OP_PUBKEY", "OP_PUBKEYHASH",
 243     ("OP_INVALIDOPCODE", 0xFFFF),
 244 ])
 245
 246
 247 def script_GetOp(bytes):
 248     i = 0
 249     while i < len(bytes):
 250         vch = None
 251         opcode = ord(bytes[i])
 252         i += 1
 253         if opcode >= opcodes.OP_SINGLEBYTE_END:
 254             opcode <<= 8
 255             opcode |= ord(bytes[i])
 256             i += 1
 257
 258         if opcode <= opcodes.OP_PUSHDATA4:
 259             nSize = opcode
 260             if opcode == opcodes.OP_PUSHDATA1:
 261                 nSize = ord(bytes[i])
 262                 i += 1
 263             elif opcode == opcodes.OP_PUSHDATA2:
 264                 (nSize,) = struct.unpack_from('<H', bytes, i)
 265                 i += 2
 266             elif opcode == opcodes.OP_PUSHDATA4:
 267                 (nSize,) = struct.unpack_from('<I', bytes, i)
 268                 i += 4
 269             vch = bytes[i:i+nSize]
 270             i += nSize
 271
 272         yield (opcode, vch, i)
 273
 274
 275 def script_GetOpName(opcode):
 276     return (opcodes.whatis(opcode)).replace("OP_", "")
 277
 278
 279 def decode_script(bytes):
 280     result = ''
 281     for (opcode, vch, i) in script_GetOp(bytes):
 282         if len(result) > 0: result += " "
 283         if opcode <= opcodes.OP_PUSHDATA4:
 284             result += "%d:"%(opcode,)
 285             result += short_hex(vch)
 286         else:
 287             result += script_GetOpName(opcode)
 288     return result
 289
 290
 291 def match_decoded(decoded, to_match):
 292     if len(decoded) != len(to_match):
 293         return False;
 294     for i in range(len(decoded)):
 295         if to_match[i] == opcodes.OP_PUSHDATA4 and decoded[i][0] <= opcodes.OP_PUSHDATA4 and decoded[i][0]>0:
 296             continue  # Opcodes below OP_PUSHDATA4 all just push data onto stack, and are equivalent.
 297         if to_match[i] != decoded[i][0]:
 298             return False
 299     return True
 300
 301
 302 def parse_sig(x_sig):
 303     s = []
 304     for sig in x_sig:
 305         if sig[-2:] == '01':
 306             s.append(sig[:-2])
 307         else:
 308             assert sig == NO_SIGNATURE
 309             s.append(None)
 310     return s
 311
 312 def is_extended_pubkey(x_pubkey):
 313     return x_pubkey[0:2] in ['fe', 'ff']
 314
 315 def x_to_xpub(x_pubkey):
 316     if x_pubkey[0:2] == 'ff':
 317         from account import BIP32_Account
 318         xpub, s = BIP32_Account.parse_xpubkey(x_pubkey)
 319         return xpub
 320
 321
 322
 323 def parse_xpub(x_pubkey):
 324     if x_pubkey[0:2] == 'ff':
 325         from account import BIP32_Account
 326         xpub, s = BIP32_Account.parse_xpubkey(x_pubkey)
 327         pubkey = BIP32_Account.derive_pubkey_from_xpub(xpub, s[0], s[1])
 328     elif x_pubkey[0:2] == 'fe':
 329         from account import OldAccount
 330         mpk, s = OldAccount.parse_xpubkey(x_pubkey)
 331         pubkey = OldAccount.get_pubkey_from_mpk(mpk.decode('hex'), s[0], s[1])
 332     else:
 333         pubkey = x_pubkey
 334     return pubkey
 335
 336
 337 def parse_scriptSig(d, bytes):
 338     try:
 339         decoded = [ x for x in script_GetOp(bytes) ]
 340     except Exception:
 341         # coinbase transactions raise an exception
 342         print_error("cannot find address in input script", bytes.encode('hex'))
 343         return
 344
 345     # payto_pubkey
 346     match = [ opcodes.OP_PUSHDATA4 ]
 347     if match_decoded(decoded, match):
 348         sig = decoded[0][1].encode('hex')
 349         d['address'] = "(pubkey)"
 350         d['signatures'] = [sig]
 351         d['num_sig'] = 1
 352         d['x_pubkeys'] = ["(pubkey)"]
 353         d['pubkeys'] = ["(pubkey)"]
 354         return
 355
 356     # non-generated TxIn transactions push a signature
 357     # (seventy-something bytes) and then their public key
 358     # (65 bytes) onto the stack:
 359     match = [ opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4 ]
 360     if match_decoded(decoded, match):
 361         sig = decoded[0][1].encode('hex')
 362         x_pubkey = decoded[1][1].encode('hex')
 363         try:
 364             signatures = parse_sig([sig])
 365             pubkey = parse_xpub(x_pubkey)
 366         except:
 367             import traceback
 368             traceback.print_exc(file=sys.stdout)
 369             print_error("cannot find address in input script", bytes.encode('hex'))
 370             return
 371         d['signatures'] = signatures
 372         d['x_pubkeys'] = [x_pubkey]
 373         d['num_sig'] = 1
 374         d['pubkeys'] = [pubkey]
 375         d['address'] = public_key_to_bc_address(pubkey.decode('hex'))
 376         return
 377
 378     # p2sh transaction, 2 of n
 379     match = [ opcodes.OP_0 ]
 380     while len(match) < len(decoded):
 381         match.append(opcodes.OP_PUSHDATA4)
 382
 383     if not match_decoded(decoded, match):
 384         print_error("cannot find address in input script", bytes.encode('hex'))
 385         return
 386
 387     x_sig = map(lambda x:x[1].encode('hex'), decoded[1:-1])
 388     d['signatures'] = parse_sig(x_sig)
 389     d['num_sig'] = 2
 390
 391     dec2 = [ x for x in script_GetOp(decoded[-1][1]) ]
 392     match_2of2 = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_2, opcodes.OP_CHECKMULTISIG ]
 393     match_2of3 = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_3, opcodes.OP_CHECKMULTISIG ]
 394     if match_decoded(dec2, match_2of2):
 395         x_pubkeys = [ dec2[1][1].encode('hex'), dec2[2][1].encode('hex') ]
 396     elif match_decoded(dec2, match_2of3):
 397         x_pubkeys = [ dec2[1][1].encode('hex'), dec2[2][1].encode('hex'), dec2[3][1].encode('hex') ]
 398     else:
 399         print_error("cannot find address in input script", bytes.encode('hex'))
 400         return
 401
 402     d['x_pubkeys'] = x_pubkeys
 403     pubkeys = map(parse_xpub, x_pubkeys)
 404     d['pubkeys'] = pubkeys
 405     redeemScript = Transaction.multisig_script(pubkeys,2)
 406     d['redeemScript'] = redeemScript
 407     d['address'] = hash_160_to_bc_address(hash_160(redeemScript.decode('hex')), 5)
 408
 409
 410
 411
 412 def get_address_from_output_script(bytes):
 413     decoded = [ x for x in script_GetOp(bytes) ]
 414
 415     # The Genesis Block, self-payments, and pay-by-IP-address payments look like:
 416     # 65 BYTES:... CHECKSIG
 417     match = [ opcodes.OP_PUSHDATA4, opcodes.OP_CHECKSIG ]
 418     if match_decoded(decoded, match):
 419         return 'pubkey', decoded[0][1].encode('hex')
 420
 421     # Pay-by-Bitcoin-address TxOuts look like:
 422     # DUP HASH160 20 BYTES:... EQUALVERIFY CHECKSIG
 423     match = [ opcodes.OP_DUP, opcodes.OP_HASH160, opcodes.OP_PUSHDATA4, opcodes.OP_EQUALVERIFY, opcodes.OP_CHECKSIG ]
 424     if match_decoded(decoded, match):
 425         return 'address', hash_160_to_bc_address(decoded[2][1])
 426
 427     # p2sh
 428     match = [ opcodes.OP_HASH160, opcodes.OP_PUSHDATA4, opcodes.OP_EQUAL ]
 429     if match_decoded(decoded, match):
 430         return 'address', hash_160_to_bc_address(decoded[1][1],5)
 431
 432     return "(None)", "(None)"
 433
 434
 435
 436
 437
 438 def parse_input(vds):
 439     d = {}
 440     prevout_hash = hash_encode(vds.read_bytes(32))
 441     prevout_n = vds.read_uint32()
 442     scriptSig = vds.read_bytes(vds.read_compact_size())
 443     sequence = vds.read_uint32()
 444     if prevout_hash == '00'*32:
 445         d['is_coinbase'] = True
 446     else:
 447         d['is_coinbase'] = False
 448         d['prevout_hash'] = prevout_hash
 449         d['prevout_n'] = prevout_n
 450         d['sequence'] = sequence
 451         d['pubkeys'] = []
 452         d['signatures'] = {}
 453         d['address'] = None
 454         if scriptSig:
 455             parse_scriptSig(d, scriptSig)
 456     return d
 457
 458
 459 def parse_output(vds, i):
 460     d = {}
 461     d['value'] = vds.read_int64()
 462     scriptPubKey = vds.read_bytes(vds.read_compact_size())
 463     type, address = get_address_from_output_script(scriptPubKey)
 464     d['type'] = type
 465     d['address'] = address
 466     d['scriptPubKey'] = scriptPubKey.encode('hex')
 467     d['prevout_n'] = i
 468     return d
 469
 470
 471 def deserialize(raw):
 472     vds = BCDataStream()
 473     vds.write(raw.decode('hex'))
 474     d = {}
 475     start = vds.read_cursor
 476     d['version'] = vds.read_int32()
 477     n_vin = vds.read_compact_size()
 478     d['inputs'] = []
 479     for i in xrange(n_vin):
 480         d['inputs'].append(parse_input(vds))
 481     n_vout = vds.read_compact_size()
 482     d['outputs'] = []
 483     for i in xrange(n_vout):
 484         d['outputs'].append(parse_output(vds, i))
 485     d['lockTime'] = vds.read_uint32()
 486     return d
 487
 488
 489 push_script = lambda x: op_push(len(x)/2) + x
 490
 491 class Transaction:
 492
 493     def __str__(self):
 494         if self.raw is None:
 495             self.raw = self.serialize(self.inputs, self.outputs, for_sig = None) # for_sig=-1 means do not sign
 496         return self.raw
 497
 498     def __init__(self, inputs, outputs, locktime=0):
 499         self.inputs = inputs
 500         self.outputs = outputs
 501         self.locktime = locktime
 502         self.raw = None
 503
 504     @classmethod
 505     def deserialize(klass, raw):
 506         self = klass([],[])
 507         self.update(raw)
 508         return self
 509
 510     def update(self, raw):
 511         d = deserialize(raw)
 512         self.raw = raw
 513         self.inputs = d['inputs']
 514         self.outputs = map(lambda x: (x['type'], x['address'], x['value']), d['outputs'])
 515         self.locktime = d['lockTime']
 516
 517
 518     @classmethod
 519     def sweep(klass, privkeys, network, to_address, fee):
 520         inputs = []
 521         for privkey in privkeys:
 522             pubkey = public_key_from_private_key(privkey)
 523             address = address_from_private_key(privkey)
 524             u = network.synchronous_get([ ('blockchain.address.listunspent',[address])])[0]
 525             pay_script = klass.pay_script(address)
 526             for item in u:
 527                 item['scriptPubKey'] = pay_script
 528                 item['redeemPubkey'] = pubkey
 529                 item['address'] = address
 530                 item['prevout_hash'] = item['tx_hash']
 531                 item['prevout_n'] = item['tx_pos']
 532             inputs += u
 533
 534         if not inputs:
 535             return
 536
 537         total = sum( map(lambda x:int(x.get('value')), inputs) ) - fee
 538         outputs = [('address', to_address, total)]
 539         self = klass(inputs, outputs)
 540         self.sign({ pubkey:privkey })
 541         return self
 542
 543     @classmethod
 544     def multisig_script(klass, public_keys, num=None):
 545         n = len(public_keys)
 546         if num is None: num = n
 547         # supports only "2 of 2", and "2 of 3" transactions
 548         assert num <= n and n in [2,3]
 549
 550         if num==2:
 551             s = '52'
 552         elif num == 3:
 553             s = '53'
 554         else:
 555             raise
 556
 557         for k in public_keys:
 558             s += op_push(len(k)/2)
 559             s += k
 560         if n==2:
 561             s += '52'
 562         elif n==3:
 563             s += '53'
 564         else:
 565             raise
 566         s += 'ae'
 567
 568         return s
 569
 570
 571     @classmethod
 572     def pay_script(self, type, addr):
 573         if type == 'op_return':
 574             h = addr.encode('hex')
 575             return '6a' + push_script(h)
 576         else:
 577             assert type == 'address'
 578         addrtype, hash_160 = bc_address_to_hash_160(addr)
 579         if addrtype == 0:
 580             script = '76a9'                                      # op_dup, op_hash_160
 581             script += push_script(hash_160.encode('hex'))
 582             script += '88ac'                                     # op_equalverify, op_checksig
 583         elif addrtype == 5:
 584             script = 'a9'                                        # op_hash_160
 585             script += push_script(hash_160.encode('hex'))
 586             script += '87'                                       # op_equal
 587         else:
 588             raise
 589         return script
 590
 591
 592     @classmethod
 593     def serialize(klass, inputs, outputs, for_sig = None ):
 594
 595         s  = int_to_hex(1,4)                                         # version
 596         s += var_int( len(inputs) )                                  # number of inputs
 597         for i in range(len(inputs)):
 598             txin = inputs[i]
 599
 600             s += txin['prevout_hash'].decode('hex')[::-1].encode('hex')   # prev hash
 601             s += int_to_hex(txin['prevout_n'],4)                          # prev index
 602
 603             p2sh = txin.get('redeemScript') is not None
 604             num_sig = txin['num_sig']
 605             address = txin['address']
 606
 607             x_signatures = txin['signatures']
 608             signatures = filter(lambda x: x is not None, x_signatures)
 609             is_complete = len(signatures) == num_sig
 610
 611             if for_sig is None:
 612                 # if we have enough signatures, we use the actual pubkeys
 613                 # use extended pubkeys (with bip32 derivation)
 614                 sig_list = []
 615                 if is_complete:
 616                     pubkeys = txin['pubkeys']
 617                     for signature in signatures:
 618                         sig_list.append(signature + '01')
 619                 else:
 620                     pubkeys = txin['x_pubkeys']
 621                     for signature in x_signatures:
 622                         sig_list.append((signature + '01') if signature is not None else NO_SIGNATURE)
 623
 624                 sig_list = ''.join( map( lambda x: push_script(x), sig_list))
 625                 if not p2sh:
 626                     script = sig_list
 627                     script += push_script(pubkeys[0])
 628                 else:
 629                     script = '00'                                    # op_0
 630                     script += sig_list
 631                     redeem_script = klass.multisig_script(pubkeys,2)
 632                     script += push_script(redeem_script)
 633
 634             elif for_sig==i:
 635                 script = txin['redeemScript'] if p2sh else klass.pay_script('address', address)
 636             else:
 637                 script = ''
 638             s += var_int( len(script)/2 )                            # script length
 639             s += script
 640             s += "ffffffff"                                          # sequence
 641
 642         s += var_int( len(outputs) )                                 # number of outputs
 643         for output in outputs:
 644             type, addr, amount = output
 645             s += int_to_hex( amount, 8)                              # amount
 646             script = klass.pay_script(type, addr)
 647             s += var_int( len(script)/2 )                           #  script length
 648             s += script                                             #  script
 649         s += int_to_hex(0,4)                                        #  lock time
 650         if for_sig is not None and for_sig != -1:
 651             s += int_to_hex(1, 4)                                   #  hash type
 652         return s
 653
 654
 655     def tx_for_sig(self,i):
 656         return self.serialize(self.inputs, self.outputs, for_sig = i)
 657
 658
 659     def hash(self):
 660         return Hash(self.raw.decode('hex') )[::-1].encode('hex')
 661
 662     def add_signature(self, i, pubkey, sig):
 663         print_error("adding signature for", pubkey)
 664         txin = self.inputs[i]
 665         pubkeys = txin['pubkeys']
 666         ii = pubkeys.index(pubkey)
 667         txin['signatures'][ii] = sig
 668         txin['x_pubkeys'][ii] = pubkey
 669         self.inputs[i] = txin
 670         self.raw = self.serialize(self.inputs, self.outputs)
 671
 672
 673     def signature_count(self):
 674         r = 0
 675         s = 0
 676         for txin in self.inputs:
 677             signatures = filter(lambda x: x is not None, txin['signatures'])
 678             s += len(signatures)
 679             r += txin['num_sig']
 680         return s, r
 681
 682
 683     def is_complete(self):
 684         s, r = self.signature_count()
 685         return r == s
 686
 687
 688     def inputs_to_sign(self):
 689         from account import BIP32_Account, OldAccount
 690         xpub_list = []
 691         addr_list = set()
 692         for txin in self.inputs:
 693             x_signatures = txin['signatures']
 694             signatures = filter(lambda x: x is not None, x_signatures)
 695
 696             if len(signatures) == txin['num_sig']:
 697                 # input is complete
 698                 continue
 699
 700             for k, x_pubkey in enumerate(txin['x_pubkeys']):
 701
 702                 if x_signatures[k] is not None:
 703                     # this pubkey already signed
 704                     continue
 705
 706                 if x_pubkey[0:2] == 'ff':
 707                     xpub, sequence = BIP32_Account.parse_xpubkey(x_pubkey)
 708                     xpub_list.append((xpub,sequence))
 709                 elif x_pubkey[0:2] == 'fe':
 710                     xpub, sequence = OldAccount.parse_xpubkey(x_pubkey)
 711                     xpub_list.append((xpub,sequence))
 712                 else:
 713                     addr_list.add(txin['address'])
 714
 715         return addr_list, xpub_list
 716
 717
 718     def sign(self, keypairs):
 719         print_error("tx.sign(), keypairs:", keypairs)
 720
 721         for i, txin in enumerate(self.inputs):
 722
 723             # continue if this txin is complete
 724             signatures = filter(lambda x: x is not None, txin['signatures'])
 725             num = txin['num_sig']
 726             if len(signatures) == num:
 727                 continue
 728
 729             redeem_pubkeys = txin['pubkeys']
 730             for_sig = Hash(self.tx_for_sig(i).decode('hex'))
 731             for pubkey in redeem_pubkeys:
 732                 if pubkey in keypairs.keys():
 733                     # add signature
 734                     sec = keypairs[pubkey]
 735                     pkey = regenerate_key(sec)
 736                     secexp = pkey.secret
 737                     private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 738                     public_key = private_key.get_verifying_key()
 739                     sig = private_key.sign_digest_deterministic( for_sig, hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_der )
 740                     assert public_key.verify_digest( sig, for_sig, sigdecode = ecdsa.util.sigdecode_der)
 741                     self.add_signature(i, pubkey, sig.encode('hex'))
 742
 743
 744         print_error("is_complete", self.is_complete())
 745         self.raw = self.serialize( self.inputs, self.outputs )
 746
 747
 748     def add_pubkey_addresses(self, txlist):
 749         for i in self.inputs:
 750             if i.get("address") == "(pubkey)":
 751                 prev_tx = txlist.get(i.get('prevout_hash'))
 752                 if prev_tx:
 753                     address, value = prev_tx.get_outputs()[i.get('prevout_n')]
 754                     print_error("found pay-to-pubkey address:", address)
 755                     i["address"] = address
 756
 757
 758     def get_outputs(self):
 759         """convert pubkeys to addresses"""
 760         o = []
 761         for type, x, v in self.outputs:
 762             if type == 'address':
 763                 addr = x
 764             elif type == 'pubkey':
 765                 addr = public_key_to_bc_address(x.decode('hex'))
 766             else:
 767                 addr = "(None)"
 768             o.append((addr,v))
 769         return o
 770
 771     def get_output_addresses(self):
 772         return map(lambda x:x[0], self.get_outputs())
 773
 774
 775     def has_address(self, addr):
 776         found = False
 777         for txin in self.inputs:
 778             if addr == txin.get('address'):
 779                 found = True
 780                 break
 781         if addr in self.get_output_addresses():
 782             found = True
 783
 784         return found
 785
 786
 787     def get_value(self, addresses, prevout_values):
 788         # return the balance for that tx
 789         is_relevant = False
 790         is_send = False
 791         is_pruned = False
 792         is_partial = False
 793         v_in = v_out = v_out_mine = 0
 794
 795         for item in self.inputs:
 796             addr = item.get('address')
 797             if addr in addresses:
 798                 is_send = True
 799                 is_relevant = True
 800                 key = item['prevout_hash']  + ':%d'%item['prevout_n']
 801                 value = prevout_values.get( key )
 802                 if value is None:
 803                     is_pruned = True
 804                 else:
 805                     v_in += value
 806             else:
 807                 is_partial = True
 808
 809         if not is_send: is_partial = False
 810
 811         for addr, value in self.get_outputs():
 812             v_out += value
 813             if addr in addresses:
 814                 v_out_mine += value
 815                 is_relevant = True
 816
 817         if is_pruned:
 818             # some inputs are mine:
 819             fee = None
 820             if is_send:
 821                 v = v_out_mine - v_out
 822             else:
 823                 # no input is mine
 824                 v = v_out_mine
 825
 826         else:
 827             v = v_out_mine - v_in
 828
 829             if is_partial:
 830                 # some inputs are mine, but not all
 831                 fee = None
 832                 is_send = v < 0
 833             else:
 834                 # all inputs are mine
 835                 fee = v_out - v_in
 836
 837         return is_relevant, is_send, v, fee
 838
 839
 840     def as_dict(self):
 841         import json
 842         out = {
 843             "hex":self.raw,
 844             "complete":self.is_complete()
 845             }
 846         return out
 847
 848
 849     def requires_fee(self, verifier):
 850         # see https://en.bitcoin.it/wiki/Transaction_fees
 851         threshold = 57600000
 852         size = len(self.raw)/2
 853         if size >= 10000:
 854             return True
 855
 856         for o in self.get_outputs():
 857             value = o[1]
 858             if value < 1000000:
 859                 return True
 860         sum = 0
 861         for i in self.inputs:
 862             age = verifier.get_confirmations(i["prevout_hash"])[0]
 863             sum += i["value"] * age
 864         priority = sum / size
 865         print_error(priority, threshold)
 866         return priority < threshold
 867
 868
 869