fix signatures returned by get_address_from_input_script. fixes #653
[electrum-nvc.git] / 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 from bitcoin import *
24 from util import print_error
25 import time
26 import struct
27
28 #
29 # Workalike python implementation of Bitcoin's CDataStream class.
30 #
31 import struct
32 import StringIO
33 import mmap
34
35 class SerializationError(Exception):
36     """ Thrown when there's a problem deserializing or serializing """
37
38 class BCDataStream(object):
39     def __init__(self):
40         self.input = None
41         self.read_cursor = 0
42
43     def clear(self):
44         self.input = None
45         self.read_cursor = 0
46
47     def write(self, bytes):  # Initialize with string of bytes
48         if self.input is None:
49             self.input = bytes
50         else:
51             self.input += bytes
52
53     def map_file(self, file, start):  # Initialize with bytes from file
54         self.input = mmap.mmap(file.fileno(), 0, access=mmap.ACCESS_READ)
55         self.read_cursor = start
56
57     def seek_file(self, position):
58         self.read_cursor = position
59         
60     def close_file(self):
61         self.input.close()
62
63     def read_string(self):
64         # Strings are encoded depending on length:
65         # 0 to 252 :  1-byte-length followed by bytes (if any)
66         # 253 to 65,535 : byte'253' 2-byte-length followed by bytes
67         # 65,536 to 4,294,967,295 : byte '254' 4-byte-length followed by bytes
68         # ... and the Bitcoin client is coded to understand:
69         # greater than 4,294,967,295 : byte '255' 8-byte-length followed by bytes of string
70         # ... but I don't think it actually handles any strings that big.
71         if self.input is None:
72             raise SerializationError("call write(bytes) before trying to deserialize")
73
74         try:
75             length = self.read_compact_size()
76         except IndexError:
77             raise SerializationError("attempt to read past end of buffer")
78
79         return self.read_bytes(length)
80
81     def write_string(self, string):
82         # Length-encoded as with read-string
83         self.write_compact_size(len(string))
84         self.write(string)
85
86     def read_bytes(self, length):
87         try:
88             result = self.input[self.read_cursor:self.read_cursor+length]
89             self.read_cursor += length
90             return result
91         except IndexError:
92             raise SerializationError("attempt to read past end of buffer")
93
94         return ''
95
96     def read_boolean(self): return self.read_bytes(1)[0] != chr(0)
97     def read_int16(self): return self._read_num('<h')
98     def read_uint16(self): return self._read_num('<H')
99     def read_int32(self): return self._read_num('<i')
100     def read_uint32(self): return self._read_num('<I')
101     def read_int64(self): return self._read_num('<q')
102     def read_uint64(self): return self._read_num('<Q')
103
104     def write_boolean(self, val): return self.write(chr(1) if val else chr(0))
105     def write_int16(self, val): return self._write_num('<h', val)
106     def write_uint16(self, val): return self._write_num('<H', val)
107     def write_int32(self, val): return self._write_num('<i', val)
108     def write_uint32(self, val): return self._write_num('<I', val)
109     def write_int64(self, val): return self._write_num('<q', val)
110     def write_uint64(self, val): return self._write_num('<Q', val)
111
112     def read_compact_size(self):
113         size = ord(self.input[self.read_cursor])
114         self.read_cursor += 1
115         if size == 253:
116             size = self._read_num('<H')
117         elif size == 254:
118             size = self._read_num('<I')
119         elif size == 255:
120             size = self._read_num('<Q')
121         return size
122
123     def write_compact_size(self, size):
124         if size < 0:
125             raise SerializationError("attempt to write size < 0")
126         elif size < 253:
127             self.write(chr(size))
128         elif size < 2**16:
129             self.write('\xfd')
130             self._write_num('<H', size)
131         elif size < 2**32:
132             self.write('\xfe')
133             self._write_num('<I', size)
134         elif size < 2**64:
135             self.write('\xff')
136             self._write_num('<Q', size)
137
138     def _read_num(self, format):
139         (i,) = struct.unpack_from(format, self.input, self.read_cursor)
140         self.read_cursor += struct.calcsize(format)
141         return i
142
143     def _write_num(self, format, num):
144         s = struct.pack(format, num)
145         self.write(s)
146
147 #
148 # enum-like type
149 # From the Python Cookbook, downloaded from http://code.activestate.com/recipes/67107/
150 #
151 import types, string, exceptions
152
153 class EnumException(exceptions.Exception):
154     pass
155
156 class Enumeration:
157     def __init__(self, name, enumList):
158         self.__doc__ = name
159         lookup = { }
160         reverseLookup = { }
161         i = 0
162         uniqueNames = [ ]
163         uniqueValues = [ ]
164         for x in enumList:
165             if type(x) == types.TupleType:
166                 x, i = x
167             if type(x) != types.StringType:
168                 raise EnumException, "enum name is not a string: " + x
169             if type(i) != types.IntType:
170                 raise EnumException, "enum value is not an integer: " + i
171             if x in uniqueNames:
172                 raise EnumException, "enum name is not unique: " + x
173             if i in uniqueValues:
174                 raise EnumException, "enum value is not unique for " + x
175             uniqueNames.append(x)
176             uniqueValues.append(i)
177             lookup[x] = i
178             reverseLookup[i] = x
179             i = i + 1
180         self.lookup = lookup
181         self.reverseLookup = reverseLookup
182     def __getattr__(self, attr):
183         if not self.lookup.has_key(attr):
184             raise AttributeError
185         return self.lookup[attr]
186     def whatis(self, value):
187         return self.reverseLookup[value]
188
189
190 # This function comes from bitcointools, bct-LICENSE.txt.
191 def long_hex(bytes):
192     return bytes.encode('hex_codec')
193
194 # This function comes from bitcointools, bct-LICENSE.txt.
195 def short_hex(bytes):
196     t = bytes.encode('hex_codec')
197     if len(t) < 11:
198         return t
199     return t[0:4]+"..."+t[-4:]
200
201
202
203
204 def parse_redeemScript(bytes):
205     dec = [ x for x in script_GetOp(bytes.decode('hex')) ]
206
207     # 2 of 2
208     match = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_2, opcodes.OP_CHECKMULTISIG ]
209     if match_decoded(dec, match):
210         pubkeys = [ dec[1][1].encode('hex'), dec[2][1].encode('hex') ]
211         return 2, pubkeys
212
213     # 2 of 3
214     match = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_3, opcodes.OP_CHECKMULTISIG ]
215     if match_decoded(dec, match):
216         pubkeys = [ dec[1][1].encode('hex'), dec[2][1].encode('hex'), dec[3][1].encode('hex') ]
217         return 2, pubkeys
218
219
220
221 opcodes = Enumeration("Opcodes", [
222     ("OP_0", 0), ("OP_PUSHDATA1",76), "OP_PUSHDATA2", "OP_PUSHDATA4", "OP_1NEGATE", "OP_RESERVED",
223     "OP_1", "OP_2", "OP_3", "OP_4", "OP_5", "OP_6", "OP_7",
224     "OP_8", "OP_9", "OP_10", "OP_11", "OP_12", "OP_13", "OP_14", "OP_15", "OP_16",
225     "OP_NOP", "OP_VER", "OP_IF", "OP_NOTIF", "OP_VERIF", "OP_VERNOTIF", "OP_ELSE", "OP_ENDIF", "OP_VERIFY",
226     "OP_RETURN", "OP_TOALTSTACK", "OP_FROMALTSTACK", "OP_2DROP", "OP_2DUP", "OP_3DUP", "OP_2OVER", "OP_2ROT", "OP_2SWAP",
227     "OP_IFDUP", "OP_DEPTH", "OP_DROP", "OP_DUP", "OP_NIP", "OP_OVER", "OP_PICK", "OP_ROLL", "OP_ROT",
228     "OP_SWAP", "OP_TUCK", "OP_CAT", "OP_SUBSTR", "OP_LEFT", "OP_RIGHT", "OP_SIZE", "OP_INVERT", "OP_AND",
229     "OP_OR", "OP_XOR", "OP_EQUAL", "OP_EQUALVERIFY", "OP_RESERVED1", "OP_RESERVED2", "OP_1ADD", "OP_1SUB", "OP_2MUL",
230     "OP_2DIV", "OP_NEGATE", "OP_ABS", "OP_NOT", "OP_0NOTEQUAL", "OP_ADD", "OP_SUB", "OP_MUL", "OP_DIV",
231     "OP_MOD", "OP_LSHIFT", "OP_RSHIFT", "OP_BOOLAND", "OP_BOOLOR",
232     "OP_NUMEQUAL", "OP_NUMEQUALVERIFY", "OP_NUMNOTEQUAL", "OP_LESSTHAN",
233     "OP_GREATERTHAN", "OP_LESSTHANOREQUAL", "OP_GREATERTHANOREQUAL", "OP_MIN", "OP_MAX",
234     "OP_WITHIN", "OP_RIPEMD160", "OP_SHA1", "OP_SHA256", "OP_HASH160",
235     "OP_HASH256", "OP_CODESEPARATOR", "OP_CHECKSIG", "OP_CHECKSIGVERIFY", "OP_CHECKMULTISIG",
236     "OP_CHECKMULTISIGVERIFY",
237     ("OP_SINGLEBYTE_END", 0xF0),
238     ("OP_DOUBLEBYTE_BEGIN", 0xF000),
239     "OP_PUBKEY", "OP_PUBKEYHASH",
240     ("OP_INVALIDOPCODE", 0xFFFF),
241 ])
242
243
244 def script_GetOp(bytes):
245     i = 0
246     while i < len(bytes):
247         vch = None
248         opcode = ord(bytes[i])
249         i += 1
250         if opcode >= opcodes.OP_SINGLEBYTE_END:
251             opcode <<= 8
252             opcode |= ord(bytes[i])
253             i += 1
254
255         if opcode <= opcodes.OP_PUSHDATA4:
256             nSize = opcode
257             if opcode == opcodes.OP_PUSHDATA1:
258                 nSize = ord(bytes[i])
259                 i += 1
260             elif opcode == opcodes.OP_PUSHDATA2:
261                 (nSize,) = struct.unpack_from('<H', bytes, i)
262                 i += 2
263             elif opcode == opcodes.OP_PUSHDATA4:
264                 (nSize,) = struct.unpack_from('<I', bytes, i)
265                 i += 4
266             vch = bytes[i:i+nSize]
267             i += nSize
268
269         yield (opcode, vch, i)
270
271
272 def script_GetOpName(opcode):
273     return (opcodes.whatis(opcode)).replace("OP_", "")
274
275
276 def decode_script(bytes):
277     result = ''
278     for (opcode, vch, i) in script_GetOp(bytes):
279         if len(result) > 0: result += " "
280         if opcode <= opcodes.OP_PUSHDATA4:
281             result += "%d:"%(opcode,)
282             result += short_hex(vch)
283         else:
284             result += script_GetOpName(opcode)
285     return result
286
287
288 def match_decoded(decoded, to_match):
289     if len(decoded) != len(to_match):
290         return False;
291     for i in range(len(decoded)):
292         if to_match[i] == opcodes.OP_PUSHDATA4 and decoded[i][0] <= opcodes.OP_PUSHDATA4 and decoded[i][0]>0:
293             continue  # Opcodes below OP_PUSHDATA4 all just push data onto stack, and are equivalent.
294         if to_match[i] != decoded[i][0]:
295             return False
296     return True
297
298 def get_address_from_input_script(bytes):
299     try:
300         decoded = [ x for x in script_GetOp(bytes) ]
301     except Exception:
302         # coinbase transactions raise an exception
303         print_error("cannot find address in input script", bytes.encode('hex'))
304         return [], {}, "(None)"
305
306     # payto_pubkey
307     match = [ opcodes.OP_PUSHDATA4 ]
308     if match_decoded(decoded, match):
309         return None, {}, "(pubkey)"
310
311     # non-generated TxIn transactions push a signature
312     # (seventy-something bytes) and then their public key
313     # (65 bytes) onto the stack:
314     match = [ opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4 ]
315     if match_decoded(decoded, match):
316         sig = decoded[0][1].encode('hex')
317         pubkey = decoded[1][1].encode('hex')
318         return [pubkey], {pubkey:sig}, public_key_to_bc_address(pubkey.decode('hex'))
319
320     # p2sh transaction, 2 of n
321     match = [ opcodes.OP_0 ]
322     while len(match) < len(decoded):
323         match.append(opcodes.OP_PUSHDATA4)
324
325     if match_decoded(decoded, match):
326
327         redeemScript = decoded[-1][1]
328         num = len(match) - 2
329         signatures = map(lambda x:x[1][:-1].encode('hex'), decoded[1:-1])
330
331         dec2 = [ x for x in script_GetOp(redeemScript) ]
332
333         # 2 of 2
334         match2 = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_2, opcodes.OP_CHECKMULTISIG ]
335         if match_decoded(dec2, match2):
336             pubkeys = [ dec2[1][1].encode('hex'), dec2[2][1].encode('hex') ]
337             return pubkeys, signatures, hash_160_to_bc_address(hash_160(redeemScript), 5)
338  
339         # 2 of 3
340         match2 = [ opcodes.OP_2, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_PUSHDATA4, opcodes.OP_3, opcodes.OP_CHECKMULTISIG ]
341         if match_decoded(dec2, match2):
342             pubkeys = [ dec2[1][1].encode('hex'), dec2[2][1].encode('hex'), dec2[3][1].encode('hex') ]
343             return pubkeys, signatures, hash_160_to_bc_address(hash_160(redeemScript), 5)
344
345     print_error("cannot find address in input script", bytes.encode('hex'))
346     return [], {}, "(None)"
347
348
349
350 def get_address_from_output_script(bytes):
351     decoded = [ x for x in script_GetOp(bytes) ]
352
353     # The Genesis Block, self-payments, and pay-by-IP-address payments look like:
354     # 65 BYTES:... CHECKSIG
355     match = [ opcodes.OP_PUSHDATA4, opcodes.OP_CHECKSIG ]
356     if match_decoded(decoded, match):
357         return True, public_key_to_bc_address(decoded[0][1])
358
359     # Pay-by-Bitcoin-address TxOuts look like:
360     # DUP HASH160 20 BYTES:... EQUALVERIFY CHECKSIG
361     match = [ opcodes.OP_DUP, opcodes.OP_HASH160, opcodes.OP_PUSHDATA4, opcodes.OP_EQUALVERIFY, opcodes.OP_CHECKSIG ]
362     if match_decoded(decoded, match):
363         return False, hash_160_to_bc_address(decoded[2][1])
364
365     # p2sh
366     match = [ opcodes.OP_HASH160, opcodes.OP_PUSHDATA4, opcodes.OP_EQUAL ]
367     if match_decoded(decoded, match):
368         return False, hash_160_to_bc_address(decoded[1][1],5)
369
370     return False, "(None)"
371
372
373 class Transaction:
374     
375     def __init__(self, raw, is_complete = True):
376         self.raw = raw
377         self.deserialize()
378         self.inputs = self.d['inputs']
379         self.outputs = self.d['outputs']
380         self.outputs = map(lambda x: (x['address'],x['value']), self.outputs)
381         self.locktime = self.d['lockTime']
382
383         
384     def __str__(self):
385         return self.raw
386
387     @classmethod
388     def from_io(klass, inputs, outputs):
389         raw = klass.serialize(inputs, outputs, for_sig = -1) # for_sig=-1 means do not sign
390         self = klass(raw)
391         self.inputs = inputs
392         self.outputs = outputs
393         return self
394
395     @classmethod
396     def multisig_script(klass, public_keys, num=None):
397         n = len(public_keys)
398         if num is None: num = n
399         # supports only "2 of 2", and "2 of 3" transactions
400         assert num <= n and n in [2,3]
401     
402         if num==2:
403             s = '52'
404         elif num == 3:
405             s = '53'
406         else:
407             raise
408     
409         for k in public_keys:
410             s += var_int(len(k)/2)
411             s += k
412         if n==2:
413             s += '52'
414         elif n==3:
415             s += '53'
416         else:
417             raise
418         s += 'ae'
419
420         return s
421
422     @classmethod
423     def serialize( klass, inputs, outputs, for_sig = None ):
424
425         push_script = lambda x: op_push(len(x)/2) + x
426         s  = int_to_hex(1,4)                                         # version
427         s += var_int( len(inputs) )                                  # number of inputs
428         for i in range(len(inputs)):
429             txin = inputs[i]
430             s += txin['prevout_hash'].decode('hex')[::-1].encode('hex')   # prev hash
431             s += int_to_hex(txin['prevout_n'],4)                          # prev index
432
433             signatures = txin.get('signatures', {})
434             if for_sig is None and not signatures:
435                 script = ''
436
437             elif for_sig is None:
438                 pubkeys = txin['pubkeys']
439                 sig_list = ''
440                 for pubkey in pubkeys:
441                     sig = signatures.get(pubkey)
442                     if not sig: 
443                         continue
444                     sig = sig + '01'
445                     sig_list += push_script(sig)
446
447                 if not txin.get('redeemScript'):
448                     script = sig_list
449                     script += push_script(pubkeys[0])
450                 else:
451                     script = '00'                                    # op_0
452                     script += sig_list
453                     redeem_script = klass.multisig_script(pubkeys,2)
454                     assert redeem_script == txin.get('redeemScript')
455                     script += push_script(redeem_script)
456
457             elif for_sig==i:
458                 if txin.get('redeemScript'):
459                     script = txin['redeemScript']                    # p2sh uses the inner script
460                 else:
461                     script = txin['scriptPubKey']                    # scriptsig
462             else:
463                 script = ''
464             s += var_int( len(script)/2 )                            # script length
465             s += script
466             s += "ffffffff"                                          # sequence
467
468         s += var_int( len(outputs) )                                 # number of outputs
469         for output in outputs:
470             addr, amount = output
471             s += int_to_hex( amount, 8)                              # amount
472             addrtype, hash_160 = bc_address_to_hash_160(addr)
473             if addrtype == 0:
474                 script = '76a9'                                      # op_dup, op_hash_160
475                 script += '14'                                       # push 0x14 bytes
476                 script += hash_160.encode('hex')
477                 script += '88ac'                                     # op_equalverify, op_checksig
478             elif addrtype == 5:
479                 script = 'a9'                                        # op_hash_160
480                 script += '14'                                       # push 0x14 bytes
481                 script += hash_160.encode('hex')
482                 script += '87'                                       # op_equal
483             else:
484                 raise
485             
486             s += var_int( len(script)/2 )                           #  script length
487             s += script                                             #  script
488         s += int_to_hex(0,4)                                        #  lock time
489         if for_sig is not None and for_sig != -1:
490             s += int_to_hex(1, 4)                                   #  hash type
491         return s
492
493
494     def tx_for_sig(self,i):
495         return self.serialize(self.inputs, self.outputs, for_sig = i)
496
497
498     def hash(self):
499         return Hash(self.raw.decode('hex') )[::-1].encode('hex')
500
501     def add_signature(self, i, pubkey, sig):
502         txin = self.inputs[i]
503         signatures = txin.get("signatures",{})
504         signatures[pubkey] = sig
505         txin["signatures"] = signatures
506         self.inputs[i] = txin
507         print_error("adding signature for", pubkey)
508         self.raw = self.serialize( self.inputs, self.outputs )
509
510
511     def is_complete(self):
512         for i, txin in enumerate(self.inputs):
513             redeem_script = txin.get('redeemScript')
514             num, redeem_pubkeys = parse_redeemScript(redeem_script) if redeem_script else (1, [txin.get('redeemPubkey')])
515             signatures = txin.get("signatures",{})
516             if len(signatures) == num:
517                 continue
518             else:
519                 return False
520         return True
521
522
523
524     def sign(self, keypairs):
525         print_error("tx.sign(), keypairs:", keypairs)
526
527         for i, txin in enumerate(self.inputs):
528
529             # if the input is multisig, parse redeem script
530             redeem_script = txin.get('redeemScript')
531             num, redeem_pubkeys = parse_redeemScript(redeem_script) if redeem_script else (1, [txin.get('redeemPubkey')])
532
533             # add pubkeys
534             txin["pubkeys"] = redeem_pubkeys
535             # get list of already existing signatures
536             signatures = txin.get("signatures",{})
537             # continue if this txin is complete
538             if len(signatures) == num:
539                 continue
540
541             for_sig = Hash(self.tx_for_sig(i).decode('hex'))
542             for pubkey in redeem_pubkeys:
543                 if pubkey in keypairs.keys():
544                     # add signature
545                     sec = keypairs[pubkey]
546                     pkey = regenerate_key(sec)
547                     secexp = pkey.secret
548                     private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
549                     public_key = private_key.get_verifying_key()
550                     sig = private_key.sign_digest_deterministic( for_sig, hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_der )
551                     assert public_key.verify_digest( sig, for_sig, sigdecode = ecdsa.util.sigdecode_der)
552                     self.add_signature(i, pubkey, sig.encode('hex'))
553
554
555         print_error("is_complete", self.is_complete())
556         self.raw = self.serialize( self.inputs, self.outputs )
557
558
559
560     def deserialize(self):
561         vds = BCDataStream()
562         vds.write(self.raw.decode('hex'))
563         d = {}
564         start = vds.read_cursor
565         d['version'] = vds.read_int32()
566         n_vin = vds.read_compact_size()
567         d['inputs'] = []
568         for i in xrange(n_vin):
569             d['inputs'].append(self.parse_input(vds))
570         n_vout = vds.read_compact_size()
571         d['outputs'] = []
572         for i in xrange(n_vout):
573             d['outputs'].append(self.parse_output(vds, i))
574         d['lockTime'] = vds.read_uint32()
575         self.d = d
576         return self.d
577     
578
579     def parse_input(self, vds):
580         d = {}
581         d['prevout_hash'] = hash_encode(vds.read_bytes(32))
582         d['prevout_n'] = vds.read_uint32()
583         scriptSig = vds.read_bytes(vds.read_compact_size())
584         d['sequence'] = vds.read_uint32()
585
586         if scriptSig:
587             pubkeys, signatures, address = get_address_from_input_script(scriptSig)
588         else:
589             pubkeys = []
590             signatures = {}
591             address = None
592
593         d['address'] = address
594         d['signatures'] = signatures
595         return d
596
597
598     def parse_output(self, vds, i):
599         d = {}
600         d['value'] = vds.read_int64()
601         scriptPubKey = vds.read_bytes(vds.read_compact_size())
602         is_pubkey, address = get_address_from_output_script(scriptPubKey)
603         d['is_pubkey'] = is_pubkey
604         d['address'] = address
605         d['scriptPubKey'] = scriptPubKey.encode('hex')
606         d['prevout_n'] = i
607         return d
608
609
610     def add_extra_addresses(self, txlist):
611         for i in self.inputs:
612             if i.get("address") == "(pubkey)":
613                 prev_tx = txlist.get(i.get('prevout_hash'))
614                 if prev_tx:
615                     address, value = prev_tx.outputs[i.get('prevout_n')]
616                     print_error("found pay-to-pubkey address:", address)
617                     i["address"] = address
618
619
620     def has_address(self, addr):
621         found = False
622         for txin in self.inputs:
623             if addr == txin.get('address'): 
624                 found = True
625                 break
626         for txout in self.outputs:
627             if addr == txout[0]:
628                 found = True
629                 break
630         return found
631
632
633     def get_value(self, addresses, prevout_values):
634         # return the balance for that tx
635         is_relevant = False
636         is_send = False
637         is_pruned = False
638         is_partial = False
639         v_in = v_out = v_out_mine = 0
640
641         for item in self.inputs:
642             addr = item.get('address')
643             if addr in addresses:
644                 is_send = True
645                 is_relevant = True
646                 key = item['prevout_hash']  + ':%d'%item['prevout_n']
647                 value = prevout_values.get( key )
648                 if value is None:
649                     is_pruned = True
650                 else:
651                     v_in += value
652             else:
653                 is_partial = True
654
655         if not is_send: is_partial = False
656                     
657         for item in self.outputs:
658             addr, value = item
659             v_out += value
660             if addr in addresses:
661                 v_out_mine += value
662                 is_relevant = True
663
664         if is_pruned:
665             # some inputs are mine:
666             fee = None
667             if is_send:
668                 v = v_out_mine - v_out
669             else:
670                 # no input is mine
671                 v = v_out_mine
672
673         else:
674             v = v_out_mine - v_in
675
676             if is_partial:
677                 # some inputs are mine, but not all
678                 fee = None
679                 is_send = v < 0
680             else:
681                 # all inputs are mine
682                 fee = v_out - v_in
683
684         return is_relevant, is_send, v, fee
685
686
687     def get_input_info(self):
688         info = []
689         for i in self.inputs:
690             item = { 
691                 'prevout_hash':i['prevout_hash'], 
692                 'prevout_n':i['prevout_n'],
693                 'address':i.get('address'),
694                 'KeyID':i.get('KeyID'),
695                 'scriptPubKey':i.get('scriptPubKey'),
696                 'redeemScript':i.get('redeemScript'),
697                 'redeemPubkey':i.get('redeemPubkey'),
698                 'pubkeys':i.get('pubkeys'),
699                 'signatures':i.get('signatures',{}),
700                 }
701             info.append(item)
702         return info
703
704
705     def as_dict(self):
706         import json
707         out = {
708             "hex":self.raw,
709             "complete":self.is_complete()
710             }
711
712         if not self.is_complete():
713             input_info = self.get_input_info()
714             out['input_info'] = json.dumps(input_info).replace(' ','')
715
716         return out
717
718
719     def requires_fee(self, verifier):
720         # see https://en.bitcoin.it/wiki/Transaction_fees
721         threshold = 57600000
722         size = len(self.raw)/2
723         if size >= 10000: 
724             return True
725
726         for o in self.outputs:
727             value = o[1]
728             if value < 1000000:
729                 return True
730         sum = 0
731         for i in self.inputs:
732             age = verifier.get_confirmations(i["prevout_hash"])[0]
733             sum += i["value"] * age
734         priority = sum / size
735         print_error(priority, threshold)
736         return priority < threshold 
737
738
739
740     def add_input_info(self, input_info):
741         for i, txin in enumerate(self.inputs):
742             item = input_info[i]
743             txin['address'] = item['address']
744             txin['signatures'] = item['signatures']
745             txin['scriptPubKey'] = item['scriptPubKey']
746             txin['redeemScript'] = item.get('redeemScript')
747             txin['redeemPubkey'] = item.get('redeemPubkey')
748             txin['KeyID'] = item.get('KeyID')