lib/bitcoin.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 hashlib, base64, ecdsa, re
  21 from util import print_error
  22
  23 def rev_hex(s):
  24     return s.decode('hex')[::-1].encode('hex')
  25
  26 def int_to_hex(i, length=1):
  27     s = hex(i)[2:].rstrip('L')
  28     s = "0"*(2*length - len(s)) + s
  29     return rev_hex(s)
  30
  31 def var_int(i):
  32     # https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
  33     if i<0xfd:
  34         return int_to_hex(i)
  35     elif i<=0xffff:
  36         return "fd"+int_to_hex(i,2)
  37     elif i<=0xffffffff:
  38         return "fe"+int_to_hex(i,4)
  39     else:
  40         return "ff"+int_to_hex(i,8)
  41
  42 def op_push(i):
  43     if i<0x4c:
  44         return int_to_hex(i)
  45     elif i<0xff:
  46         return '4c' + int_to_hex(i)
  47     elif i<0xffff:
  48         return '4d' + int_to_hex(i,2)
  49     else:
  50         return '4e' + int_to_hex(i,4)
  51
  52
  53
  54 Hash = lambda x: hashlib.sha256(hashlib.sha256(x).digest()).digest()
  55 hash_encode = lambda x: x[::-1].encode('hex')
  56 hash_decode = lambda x: x.decode('hex')[::-1]
  57
  58
  59 # pywallet openssl private key implementation
  60
  61 def i2d_ECPrivateKey(pkey, compressed=False):
  62     if compressed:
  63         key = '3081d30201010420' + \
  64               '%064x' % pkey.secret + \
  65               'a081a53081a2020101302c06072a8648ce3d0101022100' + \
  66               '%064x' % _p + \
  67               '3006040100040107042102' + \
  68               '%064x' % _Gx + \
  69               '022100' + \
  70               '%064x' % _r + \
  71               '020101a124032200'
  72     else:
  73         key = '308201130201010420' + \
  74               '%064x' % pkey.secret + \
  75               'a081a53081a2020101302c06072a8648ce3d0101022100' + \
  76               '%064x' % _p + \
  77               '3006040100040107044104' + \
  78               '%064x' % _Gx + \
  79               '%064x' % _Gy + \
  80               '022100' + \
  81               '%064x' % _r + \
  82               '020101a144034200'
  83
  84     return key.decode('hex') + i2o_ECPublicKey(pkey.pubkey, compressed)
  85
  86 def i2o_ECPublicKey(pubkey, compressed=False):
  87     # public keys are 65 bytes long (520 bits)
  88     # 0x04 + 32-byte X-coordinate + 32-byte Y-coordinate
  89     # 0x00 = point at infinity, 0x02 and 0x03 = compressed, 0x04 = uncompressed
  90     # compressed keys: <sign> <x> where <sign> is 0x02 if y is even and 0x03 if y is odd
  91     if compressed:
  92         if pubkey.point.y() & 1:
  93             key = '03' + '%064x' % pubkey.point.x()
  94         else:
  95             key = '02' + '%064x' % pubkey.point.x()
  96     else:
  97         key = '04' + \
  98               '%064x' % pubkey.point.x() + \
  99               '%064x' % pubkey.point.y()
 100
 101     return key.decode('hex')
 102
 103 # end pywallet openssl private key implementation
 104
 105
 106
 107 ############ functions from pywallet #####################
 108
 109 def hash_160(public_key):
 110     try:
 111         md = hashlib.new('ripemd160')
 112         md.update(hashlib.sha256(public_key).digest())
 113         return md.digest()
 114     except:
 115         import ripemd
 116         md = ripemd.new(hashlib.sha256(public_key).digest())
 117         return md.digest()
 118
 119
 120 def public_key_to_bc_address(public_key):
 121     h160 = hash_160(public_key)
 122     return hash_160_to_bc_address(h160)
 123
 124 def hash_160_to_bc_address(h160, addrtype = 0):
 125     vh160 = chr(addrtype) + h160
 126     h = Hash(vh160)
 127     addr = vh160 + h[0:4]
 128     return b58encode(addr)
 129
 130 def bc_address_to_hash_160(addr):
 131     bytes = b58decode(addr, 25)
 132     return ord(bytes[0]), bytes[1:21]
 133
 134 def encode_point(pubkey, compressed=False):
 135     order = generator_secp256k1.order()
 136     p = pubkey.pubkey.point
 137     x_str = ecdsa.util.number_to_string(p.x(), order)
 138     y_str = ecdsa.util.number_to_string(p.y(), order)
 139     if compressed:
 140         return chr(2 + (p.y() & 1)) + x_str
 141     else:
 142         return chr(4) + pubkey.to_string() #x_str + y_str
 143
 144 __b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
 145 __b58base = len(__b58chars)
 146
 147 def b58encode(v):
 148     """ encode v, which is a string of bytes, to base58."""
 149
 150     long_value = 0L
 151     for (i, c) in enumerate(v[::-1]):
 152         long_value += (256**i) * ord(c)
 153
 154     result = ''
 155     while long_value >= __b58base:
 156         div, mod = divmod(long_value, __b58base)
 157         result = __b58chars[mod] + result
 158         long_value = div
 159     result = __b58chars[long_value] + result
 160
 161     # Bitcoin does a little leading-zero-compression:
 162     # leading 0-bytes in the input become leading-1s
 163     nPad = 0
 164     for c in v:
 165         if c == '\0': nPad += 1
 166         else: break
 167
 168     return (__b58chars[0]*nPad) + result
 169
 170 def b58decode(v, length):
 171     """ decode v into a string of len bytes."""
 172     long_value = 0L
 173     for (i, c) in enumerate(v[::-1]):
 174         long_value += __b58chars.find(c) * (__b58base**i)
 175
 176     result = ''
 177     while long_value >= 256:
 178         div, mod = divmod(long_value, 256)
 179         result = chr(mod) + result
 180         long_value = div
 181     result = chr(long_value) + result
 182
 183     nPad = 0
 184     for c in v:
 185         if c == __b58chars[0]: nPad += 1
 186         else: break
 187
 188     result = chr(0)*nPad + result
 189     if length is not None and len(result) != length:
 190         return None
 191
 192     return result
 193
 194
 195 def EncodeBase58Check(vchIn):
 196     hash = Hash(vchIn)
 197     return b58encode(vchIn + hash[0:4])
 198
 199 def DecodeBase58Check(psz):
 200     vchRet = b58decode(psz, None)
 201     key = vchRet[0:-4]
 202     csum = vchRet[-4:]
 203     hash = Hash(key)
 204     cs32 = hash[0:4]
 205     if cs32 != csum:
 206         return None
 207     else:
 208         return key
 209
 210 def PrivKeyToSecret(privkey):
 211     return privkey[9:9+32]
 212
 213 def SecretToASecret(secret, compressed=False, addrtype=0):
 214     vchIn = chr((addrtype+128)&255) + secret
 215     if compressed: vchIn += '\01'
 216     return EncodeBase58Check(vchIn)
 217
 218 def ASecretToSecret(key, addrtype=0):
 219     vch = DecodeBase58Check(key)
 220     if vch and vch[0] == chr((addrtype+128)&255):
 221         return vch[1:]
 222     else:
 223         return False
 224
 225 def regenerate_key(sec):
 226     b = ASecretToSecret(sec)
 227     if not b:
 228         return False
 229     b = b[0:32]
 230     secret = int('0x' + b.encode('hex'), 16)
 231     return EC_KEY(secret)
 232
 233 def GetPubKey(pubkey, compressed=False):
 234     return i2o_ECPublicKey(pubkey, compressed)
 235
 236 def GetPrivKey(pkey, compressed=False):
 237     return i2d_ECPrivateKey(pkey, compressed)
 238
 239 def GetSecret(pkey):
 240     return ('%064x' % pkey.secret).decode('hex')
 241
 242 def is_compressed(sec):
 243     b = ASecretToSecret(sec)
 244     return len(b) == 33
 245
 246
 247 def address_from_private_key(sec):
 248     # rebuild public key from private key, compressed or uncompressed
 249     pkey = regenerate_key(sec)
 250     assert pkey
 251
 252     # figure out if private key is compressed
 253     compressed = is_compressed(sec)
 254
 255     # rebuild private and public key from regenerated secret
 256     private_key = GetPrivKey(pkey, compressed)
 257     public_key = GetPubKey(pkey.pubkey, compressed)
 258     address = public_key_to_bc_address(public_key)
 259     return address
 260
 261
 262 def is_valid(addr):
 263     ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
 264     if not ADDRESS_RE.match(addr): return False
 265     try:
 266         addrtype, h = bc_address_to_hash_160(addr)
 267     except:
 268         return False
 269     return addr == hash_160_to_bc_address(h, addrtype)
 270
 271
 272 ########### end pywallet functions #######################
 273
 274 # secp256k1, http://www.oid-info.com/get/1.3.132.0.10
 275 _p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2FL
 276 _r = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141L
 277 _b = 0x0000000000000000000000000000000000000000000000000000000000000007L
 278 _a = 0x0000000000000000000000000000000000000000000000000000000000000000L
 279 _Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798L
 280 _Gy = 0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8L
 281 curve_secp256k1 = ecdsa.ellipticcurve.CurveFp( _p, _a, _b )
 282 generator_secp256k1 = ecdsa.ellipticcurve.Point( curve_secp256k1, _Gx, _Gy, _r )
 283 oid_secp256k1 = (1,3,132,0,10)
 284 SECP256k1 = ecdsa.curves.Curve("SECP256k1", curve_secp256k1, generator_secp256k1, oid_secp256k1 )
 285
 286 from ecdsa.util import string_to_number, number_to_string
 287
 288 def msg_magic(message):
 289     return "\x18Bitcoin Signed Message:\n" + chr( len(message) ) + message
 290
 291
 292 class EC_KEY(object):
 293     def __init__( self, secret ):
 294         self.pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, generator_secp256k1 * secret )
 295         self.privkey = ecdsa.ecdsa.Private_key( self.pubkey, secret )
 296         self.secret = secret
 297
 298     def sign_message(self, message, compressed, address):
 299         private_key = ecdsa.SigningKey.from_secret_exponent( self.secret, curve = SECP256k1 )
 300         public_key = private_key.get_verifying_key()
 301         signature = private_key.sign_digest( Hash( msg_magic(message) ), sigencode = ecdsa.util.sigencode_string )
 302         assert public_key.verify_digest( signature, Hash( msg_magic(message) ), sigdecode = ecdsa.util.sigdecode_string)
 303         for i in range(4):
 304             sig = base64.b64encode( chr(27 + i + (4 if compressed else 0)) + signature )
 305             try:
 306                 self.verify_message( address, sig, message)
 307                 return sig
 308             except:
 309                 continue
 310         else:
 311             raise BaseException("error: cannot sign message")
 312
 313     @classmethod
 314     def verify_message(self, address, signature, message):
 315         """ See http://www.secg.org/download/aid-780/sec1-v2.pdf for the math """
 316         from ecdsa import numbertheory, ellipticcurve, util
 317         import msqr
 318         curve = curve_secp256k1
 319         G = generator_secp256k1
 320         order = G.order()
 321         # extract r,s from signature
 322         sig = base64.b64decode(signature)
 323         if len(sig) != 65: raise BaseException("Wrong encoding")
 324         r,s = util.sigdecode_string(sig[1:], order)
 325         nV = ord(sig[0])
 326         if nV < 27 or nV >= 35:
 327             raise BaseException("Bad encoding")
 328         if nV >= 31:
 329             compressed = True
 330             nV -= 4
 331         else:
 332             compressed = False
 333
 334         recid = nV - 27
 335         # 1.1
 336         x = r + (recid/2) * order
 337         # 1.3
 338         alpha = ( x * x * x  + curve.a() * x + curve.b() ) % curve.p()
 339         beta = msqr.modular_sqrt(alpha, curve.p())
 340         y = beta if (beta - recid) % 2 == 0 else curve.p() - beta
 341         # 1.4 the constructor checks that nR is at infinity
 342         R = ellipticcurve.Point(curve, x, y, order)
 343         # 1.5 compute e from message:
 344         h = Hash( msg_magic(message) )
 345         e = string_to_number(h)
 346         minus_e = -e % order
 347         # 1.6 compute Q = r^-1 (sR - eG)
 348         inv_r = numbertheory.inverse_mod(r,order)
 349         Q = inv_r * ( s * R + minus_e * G )
 350         public_key = ecdsa.VerifyingKey.from_public_point( Q, curve = SECP256k1 )
 351         # check that Q is the public key
 352         public_key.verify_digest( sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
 353         # check that we get the original signing address
 354         addr = public_key_to_bc_address( encode_point(public_key, compressed) )
 355         if address != addr:
 356             raise BaseException("Bad signature")
 357
 358
 359 ###################################### BIP32 ##############################
 360
 361 random_seed = lambda n: "%032x"%ecdsa.util.randrange( pow(2,n) )
 362
 363
 364
 365 def bip32_init(seed):
 366     import hmac
 367     seed = seed.decode('hex')
 368     I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
 369
 370     master_secret = I[0:32]
 371     master_chain = I[32:]
 372
 373     # public key
 374     curve = SECP256k1
 375     master_private_key = ecdsa.SigningKey.from_string( master_secret, curve = SECP256k1 )
 376     master_public_key = master_private_key.get_verifying_key()
 377     K = master_public_key.to_string()
 378     K_compressed = GetPubKey(master_public_key.pubkey,True)
 379     return master_secret, master_chain, K, K_compressed
 380
 381
 382 def CKD(k, c, n):
 383     import hmac
 384     from ecdsa.util import string_to_number, number_to_string
 385     order = generator_secp256k1.order()
 386     keypair = EC_KEY(string_to_number(k))
 387     K = GetPubKey(keypair.pubkey,True)
 388     I = hmac.new(c, K + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
 389     k_n = number_to_string( (string_to_number(I[0:32]) * string_to_number(k)) % order , order )
 390     c_n = I[32:]
 391     return k_n, c_n
 392
 393
 394 def CKD_prime(K, c, n):
 395     import hmac
 396     from ecdsa.util import string_to_number, number_to_string
 397     order = generator_secp256k1.order()
 398
 399     K_public_key = ecdsa.VerifyingKey.from_string( K, curve = SECP256k1 )
 400     K_compressed = GetPubKey(K_public_key.pubkey,True)
 401
 402     I = hmac.new(c, K_compressed + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
 403
 404     #pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, string_to_number(I[0:32]) * K_public_key.pubkey.point )
 405     public_key = ecdsa.VerifyingKey.from_public_point( string_to_number(I[0:32]) * K_public_key.pubkey.point, curve = SECP256k1 )
 406     K_n = public_key.to_string()
 407     K_n_compressed = GetPubKey(public_key.pubkey,True)
 408     c_n = I[32:]
 409
 410     return K_n, K_n_compressed, c_n
 411
 412
 413
 414 class ElectrumSequence:
 415     """  Privatekey(type,n) = Master_private_key + H(n|S|type)  """
 416
 417     def __init__(self, mpk, mpk2 = None, mpk3 = None):
 418         self.mpk = mpk
 419         self.mpk2 = mpk2
 420         self.mpk3 = mpk3
 421
 422     @classmethod
 423     def mpk_from_seed(klass, seed):
 424         curve = SECP256k1
 425         secexp = klass.stretch_key(seed)
 426         master_private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 427         master_public_key = master_private_key.get_verifying_key().to_string().encode('hex')
 428         return master_public_key
 429
 430     @classmethod
 431     def stretch_key(self,seed):
 432         oldseed = seed
 433         for i in range(100000):
 434             seed = hashlib.sha256(seed + oldseed).digest()
 435         return string_to_number( seed )
 436
 437     def get_sequence(self, sequence, mpk):
 438         for_change, n = sequence
 439         return string_to_number( Hash( "%d:%d:"%(n,for_change) + mpk.decode('hex') ) )
 440
 441     def get_address(self, sequence):
 442         if not self.mpk2:
 443             pubkey = self.get_pubkey(sequence)
 444             address = public_key_to_bc_address( pubkey.decode('hex') )
 445         elif not self.mpk3:
 446             pubkey1 = self.get_pubkey(sequence)
 447             pubkey2 = self.get_pubkey(sequence, mpk = self.mpk2)
 448             address = Transaction.multisig_script([pubkey1, pubkey2], 2)["address"]
 449         else:
 450             pubkey1 = self.get_pubkey(sequence)
 451             pubkey2 = self.get_pubkey(sequence, mpk = self.mpk2)
 452             pubkey3 = self.get_pubkey(sequence, mpk = self.mpk3)
 453             address = Transaction.multisig_script([pubkey1, pubkey2, pubkey3], 2)["address"]
 454         return address
 455
 456     def get_pubkey(self, sequence, mpk=None):
 457         curve = SECP256k1
 458         if mpk is None: mpk = self.mpk
 459         z = self.get_sequence(sequence, mpk)
 460         master_public_key = ecdsa.VerifyingKey.from_string( mpk.decode('hex'), curve = SECP256k1 )
 461         pubkey_point = master_public_key.pubkey.point + z*curve.generator
 462         public_key2 = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
 463         return '04' + public_key2.to_string().encode('hex')
 464
 465     def get_private_key_from_stretched_exponent(self, sequence, secexp):
 466         order = generator_secp256k1.order()
 467         secexp = ( secexp + self.get_sequence(sequence, self.mpk) ) % order
 468         pk = number_to_string( secexp, generator_secp256k1.order() )
 469         compressed = False
 470         return SecretToASecret( pk, compressed )
 471
 472     def get_private_key(self, sequence, seed):
 473         secexp = self.stretch_key(seed)
 474         return self.get_private_key_from_stretched_exponent(sequence, secexp)
 475
 476     def get_private_keys(self, sequence_list, seed):
 477         secexp = self.stretch_key(seed)
 478         return [ self.get_private_key_from_stretched_exponent( sequence, secexp) for sequence in sequence_list]
 479
 480     def check_seed(self, seed):
 481         curve = SECP256k1
 482         secexp = self.stretch_key(seed)
 483         master_private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 484         master_public_key = master_private_key.get_verifying_key().to_string().encode('hex')
 485         if master_public_key != self.mpk:
 486             print_error('invalid password (mpk)')
 487             raise BaseException('Invalid password')
 488         return True
 489
 490     def get_input_info(self, sequence):
 491         if not self.mpk2:
 492             pk_addr = self.get_address(sequence)
 493             redeemScript = None
 494         elif not self.mpk3:
 495             pubkey1 = self.get_pubkey(sequence)
 496             pubkey2 = self.get_pubkey(sequence,mpk=self.mpk2)
 497             pk_addr = public_key_to_bc_address( pubkey1.decode('hex') ) # we need to return that address to get the right private key
 498             redeemScript = Transaction.multisig_script([pubkey1, pubkey2], 2)['redeemScript']
 499         else:
 500             pubkey1 = self.get_pubkey(sequence)
 501             pubkey2 = self.get_pubkey(sequence, mpk=self.mpk2)
 502             pubkey3 = self.get_pubkey(sequence, mpk=self.mpk3)
 503             pk_addr = public_key_to_bc_address( pubkey1.decode('hex') ) # we need to return that address to get the right private key
 504             redeemScript = Transaction.multisig_script([pubkey1, pubkey2, pubkey3], 2)['redeemScript']
 505         return pk_addr, redeemScript
 506
 507
 508
 509
 510 class BIP32Sequence:
 511
 512     def __init__(self, mpk, mpk2 = None, mpk3 = None):
 513         self.mpk = mpk
 514         self.mpk2 = mpk2
 515         self.mpk3 = mpk3
 516
 517     @classmethod
 518     def mpk_from_seed(klass, seed):
 519         master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
 520         return master_public_key.encode('hex'), master_chain.encode('hex')
 521
 522     def get_pubkey(self, sequence, mpk = None):
 523         if not mpk: mpk = self.mpk
 524         master_public_key, master_chain = mpk
 525         K = master_public_key.decode('hex')
 526         chain = master_chain.decode('hex')
 527         for i in sequence:
 528             K, K_compressed, chain = CKD_prime(K, chain, i)
 529         return K_compressed.encode('hex')
 530
 531     def get_address(self, sequence):
 532         if not self.mpk2:
 533             pubkey = self.get_pubkey(sequence)
 534             address = public_key_to_bc_address( pubkey.decode('hex') )
 535         elif not self.mpk3:
 536             pubkey1 = self.get_pubkey(sequence)
 537             pubkey2 = self.get_pubkey(sequence, mpk = self.mpk2)
 538             address = Transaction.multisig_script([pubkey1, pubkey2], 2)["address"]
 539         else:
 540             pubkey1 = self.get_pubkey(sequence)
 541             pubkey2 = self.get_pubkey(sequence, mpk = self.mpk2)
 542             pubkey3 = self.get_pubkey(sequence, mpk = self.mpk3)
 543             address = Transaction.multisig_script([pubkey1, pubkey2, pubkey3], 2)["address"]
 544         return address
 545
 546     def get_private_key(self, sequence, seed):
 547         master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
 548         chain = master_chain
 549         k = master_secret
 550         for i in sequence:
 551             k, chain = CKD(k, chain, i)
 552         return SecretToASecret(k, True)
 553
 554     def get_private_keys(self, sequence_list, seed):
 555         return [ self.get_private_key( sequence, seed) for sequence in sequence_list]
 556
 557     def check_seed(self, seed):
 558         master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
 559         assert self.mpk == (master_public_key.encode('hex'), master_chain.encode('hex'))
 560
 561     def get_input_info(self, sequence):
 562         if not self.mpk2:
 563             pk_addr = self.get_address(sequence)
 564             redeemScript = None
 565         elif not self.mpk3:
 566             pubkey1 = self.get_pubkey(sequence)
 567             pubkey2 = self.get_pubkey(sequence, mpk=self.mpk2)
 568             pk_addr = public_key_to_bc_address( pubkey1.decode('hex') ) # we need to return that address to get the right private key
 569             redeemScript = Transaction.multisig_script([pubkey1, pubkey2], 2)['redeemScript']
 570         else:
 571             pubkey1 = self.get_pubkey(sequence)
 572             pubkey2 = self.get_pubkey(sequence, mpk=self.mpk2)
 573             pubkey3 = self.get_pubkey(sequence, mpk=self.mpk3)
 574             pk_addr = public_key_to_bc_address( pubkey1.decode('hex') ) # we need to return that address to get the right private key
 575             redeemScript = Transaction.multisig_script([pubkey1, pubkey2, pubkey3], 2)['redeemScript']
 576         return pk_addr, redeemScript
 577
 578 ################################## transactions
 579
 580 MIN_RELAY_TX_FEE = 10000
 581
 582 class Transaction:
 583
 584     def __init__(self, raw):
 585         self.raw = raw
 586         self.deserialize()
 587         self.inputs = self.d['inputs']
 588         self.outputs = self.d['outputs']
 589         self.outputs = map(lambda x: (x['address'],x['value']), self.outputs)
 590         self.input_info = None
 591         self.is_complete = True
 592
 593     @classmethod
 594     def from_io(klass, inputs, outputs):
 595         raw = klass.serialize(inputs, outputs, for_sig = -1) # for_sig=-1 means do not sign
 596         self = klass(raw)
 597         self.is_complete = False
 598         self.inputs = inputs
 599         self.outputs = outputs
 600         extras = []
 601         for i in self.inputs:
 602             e = { 'txid':i['tx_hash'], 'vout':i['index'], 'scriptPubKey':i.get('raw_output_script') }
 603             extras.append(e)
 604         self.input_info = extras
 605         return self
 606
 607     def __str__(self):
 608         return self.raw
 609
 610     @classmethod
 611     def multisig_script(klass, public_keys, num=None):
 612         n = len(public_keys)
 613         if num is None: num = n
 614         # supports only "2 of 2", and "2 of 3" transactions
 615         assert num <= n and n in [2,3]
 616
 617         if num==2:
 618             s = '52'
 619         elif num == 3:
 620             s = '53'
 621         else:
 622             raise
 623
 624         for k in public_keys:
 625             s += var_int(len(k)/2)
 626             s += k
 627         if n==2:
 628             s += '52'
 629         elif n==3:
 630             s += '53'
 631         else:
 632             raise
 633         s += 'ae'
 634
 635         out = { "address": hash_160_to_bc_address(hash_160(s.decode('hex')), 5), "redeemScript":s }
 636         return out
 637
 638     @classmethod
 639     def serialize( klass, inputs, outputs, for_sig = None ):
 640
 641         s  = int_to_hex(1,4)                                         # version
 642         s += var_int( len(inputs) )                                  # number of inputs
 643         for i in range(len(inputs)):
 644             txin = inputs[i]
 645             s += txin['tx_hash'].decode('hex')[::-1].encode('hex')   # prev hash
 646             s += int_to_hex(txin['index'],4)                         # prev index
 647
 648             if for_sig is None:
 649                 pubkeysig = txin.get('pubkeysig')
 650                 if pubkeysig:
 651                     pubkey, sig = pubkeysig[0]
 652                     sig = sig + chr(1)                               # hashtype
 653                     script  = op_push( len(sig))
 654                     script += sig.encode('hex')
 655                     script += op_push( len(pubkey))
 656                     script += pubkey.encode('hex')
 657                 else:
 658                     signatures = txin['signatures']
 659                     pubkeys = txin['pubkeys']
 660                     script = '00'                                    # op_0
 661                     for sig in signatures:
 662                         sig = sig + '01'
 663                         script += op_push(len(sig)/2)
 664                         script += sig
 665
 666                     redeem_script = klass.multisig_script(pubkeys,2).get('redeemScript')
 667                     script += op_push(len(redeem_script)/2)
 668                     script += redeem_script
 669
 670             elif for_sig==i:
 671                 if txin.get('redeemScript'):
 672                     script = txin['redeemScript']                    # p2sh uses the inner script
 673                 else:
 674                     script = txin['raw_output_script']               # scriptsig
 675             else:
 676                 script=''
 677             s += var_int( len(script)/2 )                            # script length
 678             s += script
 679             s += "ffffffff"                                          # sequence
 680
 681         s += var_int( len(outputs) )                                 # number of outputs
 682         for output in outputs:
 683             addr, amount = output
 684             s += int_to_hex( amount, 8)                              # amount
 685             addrtype, hash_160 = bc_address_to_hash_160(addr)
 686             if addrtype == 0:
 687                 script = '76a9'                                      # op_dup, op_hash_160
 688                 script += '14'                                       # push 0x14 bytes
 689                 script += hash_160.encode('hex')
 690                 script += '88ac'                                     # op_equalverify, op_checksig
 691             elif addrtype == 5:
 692                 script = 'a9'                                        # op_hash_160
 693                 script += '14'                                       # push 0x14 bytes
 694                 script += hash_160.encode('hex')
 695                 script += '87'                                       # op_equal
 696             else:
 697                 raise
 698
 699             s += var_int( len(script)/2 )                           #  script length
 700             s += script                                             #  script
 701         s += int_to_hex(0,4)                                        #  lock time
 702         if for_sig is not None and for_sig != -1:
 703             s += int_to_hex(1, 4)                                   #  hash type
 704         return s
 705
 706
 707     def for_sig(self,i):
 708         return self.serialize(self.inputs, self.outputs, for_sig = i)
 709
 710
 711     def hash(self):
 712         return Hash(self.raw.decode('hex') )[::-1].encode('hex')
 713
 714     def sign(self, private_keys):
 715         import deserialize
 716
 717         for i in range(len(self.inputs)):
 718             txin = self.inputs[i]
 719             tx_for_sig = self.serialize( self.inputs, self.outputs, for_sig = i )
 720
 721             if txin.get('redeemScript'):
 722                 # 1 parse the redeem script
 723                 num, redeem_pubkeys = deserialize.parse_redeemScript(txin.get('redeemScript'))
 724                 self.inputs[i]["pubkeys"] = redeem_pubkeys
 725
 726                 # build list of public/private keys
 727                 keypairs = {}
 728                 for sec in private_keys.values():
 729                     compressed = is_compressed(sec)
 730                     pkey = regenerate_key(sec)
 731                     pubkey = GetPubKey(pkey.pubkey, compressed)
 732                     keypairs[ pubkey.encode('hex') ] = sec
 733
 734                 # list of already existing signatures
 735                 signatures = txin.get("signatures",[])
 736                 print_error("signatures",signatures)
 737
 738                 for pubkey in redeem_pubkeys:
 739                     public_key = ecdsa.VerifyingKey.from_string(pubkey[2:].decode('hex'), curve = SECP256k1)
 740                     for s in signatures:
 741                         try:
 742                             public_key.verify_digest( s.decode('hex')[:-1], Hash( tx_for_sig.decode('hex') ), sigdecode = ecdsa.util.sigdecode_der)
 743                             break
 744                         except ecdsa.keys.BadSignatureError:
 745                             continue
 746                     else:
 747                         # check if we have a key corresponding to the redeem script
 748                         if pubkey in keypairs.keys():
 749                             # add signature
 750                             sec = keypairs[pubkey]
 751                             compressed = is_compressed(sec)
 752                             pkey = regenerate_key(sec)
 753                             secexp = pkey.secret
 754                             private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 755                             public_key = private_key.get_verifying_key()
 756                             sig = private_key.sign_digest( Hash( tx_for_sig.decode('hex') ), sigencode = ecdsa.util.sigencode_der )
 757                             assert public_key.verify_digest( sig, Hash( tx_for_sig.decode('hex') ), sigdecode = ecdsa.util.sigdecode_der)
 758                             signatures.append( sig.encode('hex') )
 759
 760                 # for p2sh, pubkeysig is a tuple (may be incomplete)
 761                 self.inputs[i]["signatures"] = signatures
 762                 print_error("signatures",signatures)
 763                 self.is_complete = len(signatures) == num
 764
 765             else:
 766                 sec = private_keys[txin['address']]
 767                 compressed = is_compressed(sec)
 768                 pkey = regenerate_key(sec)
 769                 secexp = pkey.secret
 770
 771                 private_key = ecdsa.SigningKey.from_secret_exponent( secexp, curve = SECP256k1 )
 772                 public_key = private_key.get_verifying_key()
 773                 pkey = EC_KEY(secexp)
 774                 pubkey = GetPubKey(pkey.pubkey, compressed)
 775                 sig = private_key.sign_digest( Hash( tx_for_sig.decode('hex') ), sigencode = ecdsa.util.sigencode_der )
 776                 assert public_key.verify_digest( sig, Hash( tx_for_sig.decode('hex') ), sigdecode = ecdsa.util.sigdecode_der)
 777
 778                 self.inputs[i]["pubkeysig"] = [(pubkey, sig)]
 779                 self.is_complete = True
 780
 781         self.raw = self.serialize( self.inputs, self.outputs )
 782
 783
 784     def deserialize(self):
 785         import deserialize
 786         vds = deserialize.BCDataStream()
 787         vds.write(self.raw.decode('hex'))
 788         self.d = deserialize.parse_Transaction(vds)
 789         return self.d
 790
 791
 792     def has_address(self, addr):
 793         found = False
 794         for txin in self.inputs:
 795             if addr == txin.get('address'):
 796                 found = True
 797                 break
 798         for txout in self.outputs:
 799             if addr == txout[0]:
 800                 found = True
 801                 break
 802         return found
 803
 804
 805     def get_value(self, addresses, prevout_values):
 806         # return the balance for that tx
 807         is_relevant = False
 808         is_send = False
 809         is_pruned = False
 810         is_partial = False
 811         v_in = v_out = v_out_mine = 0
 812
 813         for item in self.inputs:
 814             addr = item.get('address')
 815             if addr in addresses:
 816                 is_send = True
 817                 is_relevant = True
 818                 key = item['prevout_hash']  + ':%d'%item['prevout_n']
 819                 value = prevout_values.get( key )
 820                 if value is None:
 821                     is_pruned = True
 822                 else:
 823                     v_in += value
 824             else:
 825                 is_partial = True
 826
 827         if not is_send: is_partial = False
 828
 829         for item in self.outputs:
 830             addr, value = item
 831             v_out += value
 832             if addr in addresses:
 833                 v_out_mine += value
 834                 is_relevant = True
 835
 836         if is_pruned:
 837             # some inputs are mine:
 838             fee = None
 839             if is_send:
 840                 v = v_out_mine - v_out
 841             else:
 842                 # no input is mine
 843                 v = v_out_mine
 844
 845         else:
 846             v = v_out_mine - v_in
 847
 848             if is_partial:
 849                 # some inputs are mine, but not all
 850                 fee = None
 851                 is_send = v < 0
 852             else:
 853                 # all inputs are mine
 854                 fee = v_out - v_in
 855
 856         return is_relevant, is_send, v, fee
 857
 858     def as_dict(self):
 859         import json
 860         out = {
 861             "hex":self.raw,
 862             "complete":self.is_complete
 863             }
 864         if not self.is_complete:
 865             extras = []
 866             for i in self.inputs:
 867                 e = { 'txid':i['tx_hash'], 'vout':i['index'],
 868                       'scriptPubKey':i.get('raw_output_script'),
 869                       'KeyID':i.get('KeyID'),
 870                       'redeemScript':i.get('redeemScript'),
 871                       'signatures':i.get('signatures'),
 872                       'pubkeys':i.get('pubkeys'),
 873                       }
 874                 extras.append(e)
 875             self.input_info = extras
 876
 877             if self.input_info:
 878                 out['input_info'] = json.dumps(self.input_info).replace(' ','')
 879
 880         return out
 881
 882
 883     def requires_fee(self, verifier):
 884         # see https://en.bitcoin.it/wiki/Transaction_fees
 885         threshold = 57600000
 886         size = len(self.raw)/2
 887         if size >= 10000:
 888             return True
 889
 890         for o in self.outputs:
 891             value = o[1]
 892             if value < 1000000:
 893                 return True
 894         sum = 0
 895         for i in self.inputs:
 896             age = verifier.get_confirmations(i["tx_hash"])[0]
 897             sum += i["value"] * age
 898         priority = sum / size
 899         print_error(priority, threshold)
 900         return priority < threshold
 901
 902
 903
 904
 905 def test_bip32():
 906     seed = "ff000000000000000000000000000000"
 907     master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
 908
 909     print "secret key", master_secret.encode('hex')
 910     print "chain code", master_chain.encode('hex')
 911
 912     key_id = hash_160(master_public_key_compressed)
 913     print "keyid", key_id.encode('hex')
 914     print "base58"
 915     print "address", hash_160_to_bc_address(key_id)
 916     print "secret key", SecretToASecret(master_secret, True)
 917
 918     print "-- m/0 --"
 919     k0, c0 = CKD(master_secret, master_chain, 0)
 920     print "secret", k0.encode('hex')
 921     print "chain", c0.encode('hex')
 922     print "secret key", SecretToASecret(k0, True)
 923
 924     K0, K0_compressed, c0 = CKD_prime(master_public_key, master_chain, 0)
 925     print "address", hash_160_to_bc_address(hash_160(K0_compressed))
 926
 927     print "-- m/0/1 --"
 928     K01, K01_compressed, c01 = CKD_prime(K0, c0, 1)
 929     print "address", hash_160_to_bc_address(hash_160(K01_compressed))
 930
 931     print "-- m/0/1/3 --"
 932     K013, K013_compressed, c013 = CKD_prime(K01, c01, 3)
 933     print "address", hash_160_to_bc_address(hash_160(K013_compressed))
 934
 935     print "-- m/0/1/3/7 --"
 936     K0137, K0137_compressed, c0137 = CKD_prime(K013, c013, 7)
 937     print "address", hash_160_to_bc_address(hash_160(K0137_compressed))
 938
 939
 940
 941 if __name__ == '__main__':
 942     test_bip32()
 943
 944