1 # -*- coding: utf-8 -*-
4 # Electrum - lightweight Bitcoin client
5 # Copyright (C) 2011 thomasv@gitorious
7 # This program is free software: you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation, either version 3 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
21 import hashlib, base64, ecdsa, re
23 from util import print_error
26 return s.decode('hex')[::-1].encode('hex')
28 def int_to_hex(i, length=1):
29 s = hex(i)[2:].rstrip('L')
30 s = "0"*(2*length - len(s)) + s
34 # https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
38 return "fd"+int_to_hex(i,2)
40 return "fe"+int_to_hex(i,4)
42 return "ff"+int_to_hex(i,8)
48 return '4c' + int_to_hex(i)
50 return '4d' + int_to_hex(i,2)
52 return '4e' + int_to_hex(i,4)
57 if type(x) is unicode: x=x.encode('utf-8')
58 return hashlib.sha256(hashlib.sha256(x).digest()).digest()
59 hash_encode = lambda x: x[::-1].encode('hex')
60 hash_decode = lambda x: x.decode('hex')[::-1]
62 hmac_sha_512 = lambda x,y: hmac.new(x, y, hashlib.sha512).digest()
63 mnemonic_hash = lambda x: hmac_sha_512("Bitcoin mnemonic", x).encode('hex')
64 from version import SEED_PREFIX
65 is_seed = lambda x: hmac_sha_512("Seed version", x).encode('hex')[0:2].startswith(SEED_PREFIX)
67 # pywallet openssl private key implementation
69 def i2d_ECPrivateKey(pkey, compressed=False):
71 key = '3081d30201010420' + \
72 '%064x' % pkey.secret + \
73 'a081a53081a2020101302c06072a8648ce3d0101022100' + \
75 '3006040100040107042102' + \
81 key = '308201130201010420' + \
82 '%064x' % pkey.secret + \
83 'a081a53081a2020101302c06072a8648ce3d0101022100' + \
85 '3006040100040107044104' + \
92 return key.decode('hex') + i2o_ECPublicKey(pkey.pubkey, compressed)
94 def i2o_ECPublicKey(pubkey, compressed=False):
95 # public keys are 65 bytes long (520 bits)
96 # 0x04 + 32-byte X-coordinate + 32-byte Y-coordinate
97 # 0x00 = point at infinity, 0x02 and 0x03 = compressed, 0x04 = uncompressed
98 # compressed keys: <sign> <x> where <sign> is 0x02 if y is even and 0x03 if y is odd
100 if pubkey.point.y() & 1:
101 key = '03' + '%064x' % pubkey.point.x()
103 key = '02' + '%064x' % pubkey.point.x()
106 '%064x' % pubkey.point.x() + \
107 '%064x' % pubkey.point.y()
109 return key.decode('hex')
111 # end pywallet openssl private key implementation
115 ############ functions from pywallet #####################
117 def hash_160(public_key):
119 md = hashlib.new('ripemd160')
120 md.update(hashlib.sha256(public_key).digest())
124 md = ripemd.new(hashlib.sha256(public_key).digest())
128 def public_key_to_bc_address(public_key):
129 h160 = hash_160(public_key)
130 return hash_160_to_bc_address(h160)
132 def hash_160_to_bc_address(h160, addrtype = 0):
133 vh160 = chr(addrtype) + h160
135 addr = vh160 + h[0:4]
136 return b58encode(addr)
138 def bc_address_to_hash_160(addr):
139 bytes = b58decode(addr, 25)
140 return ord(bytes[0]), bytes[1:21]
142 def encode_point(pubkey, compressed=False):
143 order = generator_secp256k1.order()
144 p = pubkey.pubkey.point
145 x_str = ecdsa.util.number_to_string(p.x(), order)
146 y_str = ecdsa.util.number_to_string(p.y(), order)
148 return chr(2 + (p.y() & 1)) + x_str
150 return chr(4) + pubkey.to_string() #x_str + y_str
152 __b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
153 __b58base = len(__b58chars)
156 """ encode v, which is a string of bytes, to base58."""
159 for (i, c) in enumerate(v[::-1]):
160 long_value += (256**i) * ord(c)
163 while long_value >= __b58base:
164 div, mod = divmod(long_value, __b58base)
165 result = __b58chars[mod] + result
167 result = __b58chars[long_value] + result
169 # Bitcoin does a little leading-zero-compression:
170 # leading 0-bytes in the input become leading-1s
173 if c == '\0': nPad += 1
176 return (__b58chars[0]*nPad) + result
178 def b58decode(v, length):
179 """ decode v into a string of len bytes."""
181 for (i, c) in enumerate(v[::-1]):
182 long_value += __b58chars.find(c) * (__b58base**i)
185 while long_value >= 256:
186 div, mod = divmod(long_value, 256)
187 result = chr(mod) + result
189 result = chr(long_value) + result
193 if c == __b58chars[0]: nPad += 1
196 result = chr(0)*nPad + result
197 if length is not None and len(result) != length:
203 def EncodeBase58Check(vchIn):
205 return b58encode(vchIn + hash[0:4])
207 def DecodeBase58Check(psz):
208 vchRet = b58decode(psz, None)
218 def PrivKeyToSecret(privkey):
219 return privkey[9:9+32]
221 def SecretToASecret(secret, compressed=False, addrtype=0):
222 vchIn = chr((addrtype+128)&255) + secret
223 if compressed: vchIn += '\01'
224 return EncodeBase58Check(vchIn)
226 def ASecretToSecret(key, addrtype=0):
227 vch = DecodeBase58Check(key)
228 if vch and vch[0] == chr((addrtype+128)&255):
233 def regenerate_key(sec):
234 b = ASecretToSecret(sec)
238 secret = int('0x' + b.encode('hex'), 16)
239 return EC_KEY(secret)
241 def GetPubKey(pubkey, compressed=False):
242 return i2o_ECPublicKey(pubkey, compressed)
244 def GetPrivKey(pkey, compressed=False):
245 return i2d_ECPrivateKey(pkey, compressed)
248 return ('%064x' % pkey.secret).decode('hex')
250 def is_compressed(sec):
251 b = ASecretToSecret(sec)
255 def public_key_from_private_key(sec):
256 # rebuild public key from private key, compressed or uncompressed
257 pkey = regenerate_key(sec)
259 compressed = is_compressed(sec)
260 public_key = GetPubKey(pkey.pubkey, compressed)
261 return public_key.encode('hex')
264 def address_from_private_key(sec):
265 public_key = public_key_from_private_key(sec)
266 address = public_key_to_bc_address(public_key.decode('hex'))
271 ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
272 if not ADDRESS_RE.match(addr): return False
274 addrtype, h = bc_address_to_hash_160(addr)
277 return addr == hash_160_to_bc_address(h, addrtype)
280 ########### end pywallet functions #######################
283 from ecdsa.ecdsa import curve_secp256k1, generator_secp256k1
285 print "cannot import ecdsa.curve_secp256k1. You probably need to upgrade ecdsa.\nTry: sudo pip install --upgrade ecdsa"
287 from ecdsa.curves import SECP256k1
288 from ecdsa.util import string_to_number, number_to_string
290 def msg_magic(message):
291 varint = var_int(len(message))
292 encoded_varint = "".join([chr(int(varint[i:i+2], 16)) for i in xrange(0, len(varint), 2)])
294 return "\x18Bitcoin Signed Message:\n" + encoded_varint + message
297 def verify_message(address, signature, message):
299 EC_KEY.verify_message(address, signature, message)
301 except Exception as e:
302 print_error("Verification error: {0}".format(e))
307 class EC_KEY(object):
308 def __init__( self, secret ):
309 self.pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, generator_secp256k1 * secret )
310 self.privkey = ecdsa.ecdsa.Private_key( self.pubkey, secret )
313 def sign_message(self, message, compressed, address):
314 private_key = ecdsa.SigningKey.from_secret_exponent( self.secret, curve = SECP256k1 )
315 public_key = private_key.get_verifying_key()
316 signature = private_key.sign_digest_deterministic( Hash( msg_magic(message) ), hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_string )
317 assert public_key.verify_digest( signature, Hash( msg_magic(message) ), sigdecode = ecdsa.util.sigdecode_string)
319 sig = base64.b64encode( chr(27 + i + (4 if compressed else 0)) + signature )
321 self.verify_message( address, sig, message)
326 raise Exception("error: cannot sign message")
329 def verify_message(self, address, signature, message):
330 """ See http://www.secg.org/download/aid-780/sec1-v2.pdf for the math """
331 from ecdsa import numbertheory, ellipticcurve, util
333 curve = curve_secp256k1
334 G = generator_secp256k1
336 # extract r,s from signature
337 sig = base64.b64decode(signature)
338 if len(sig) != 65: raise Exception("Wrong encoding")
339 r,s = util.sigdecode_string(sig[1:], order)
341 if nV < 27 or nV >= 35:
342 raise Exception("Bad encoding")
351 x = r + (recid/2) * order
353 alpha = ( x * x * x + curve.a() * x + curve.b() ) % curve.p()
354 beta = msqr.modular_sqrt(alpha, curve.p())
355 y = beta if (beta - recid) % 2 == 0 else curve.p() - beta
356 # 1.4 the constructor checks that nR is at infinity
357 R = ellipticcurve.Point(curve, x, y, order)
358 # 1.5 compute e from message:
359 h = Hash( msg_magic(message) )
360 e = string_to_number(h)
362 # 1.6 compute Q = r^-1 (sR - eG)
363 inv_r = numbertheory.inverse_mod(r,order)
364 Q = inv_r * ( s * R + minus_e * G )
365 public_key = ecdsa.VerifyingKey.from_public_point( Q, curve = SECP256k1 )
366 # check that Q is the public key
367 public_key.verify_digest( sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
368 # check that we get the original signing address
369 addr = public_key_to_bc_address( encode_point(public_key, compressed) )
371 raise Exception("Bad signature")
374 ###################################### BIP32 ##############################
376 random_seed = lambda n: "%032x"%ecdsa.util.randrange( pow(2,n) )
377 BIP32_PRIME = 0x80000000
379 def bip32_init(seed):
381 seed = seed.decode('hex')
382 I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
384 master_secret = I[0:32]
385 master_chain = I[32:]
387 K, K_compressed = get_pubkeys_from_secret(master_secret)
388 return master_secret, master_chain, K, K_compressed
391 def get_pubkeys_from_secret(secret):
393 private_key = ecdsa.SigningKey.from_string( secret, curve = SECP256k1 )
394 public_key = private_key.get_verifying_key()
395 K = public_key.to_string()
396 K_compressed = GetPubKey(public_key.pubkey,True)
397 return K, K_compressed
401 # Child private key derivation function (from master private key)
402 # k = master private key (32 bytes)
403 # c = master chain code (extra entropy for key derivation) (32 bytes)
404 # n = the index of the key we want to derive. (only 32 bits will be used)
405 # If n is negative (i.e. the 32nd bit is set), the resulting private key's
406 # corresponding public key can NOT be determined without the master private key.
407 # However, if n is positive, the resulting private key's corresponding
408 # public key can be determined without the master private key.
411 from ecdsa.util import string_to_number, number_to_string
412 order = generator_secp256k1.order()
413 keypair = EC_KEY(string_to_number(k))
414 K = GetPubKey(keypair.pubkey,True)
416 if n & BIP32_PRIME: # We want to make a "secret" address that can't be determined from K
417 data = chr(0) + k + rev_hex(int_to_hex(n,4)).decode('hex')
418 I = hmac.new(c, data, hashlib.sha512).digest()
419 else: # We want a "non-secret" address that can be determined from K
420 I = hmac.new(c, K + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
422 k_n = number_to_string( (string_to_number(I[0:32]) + string_to_number(k)) % order , order )
426 # Child public key derivation function (from public key only)
427 # K = master public key
428 # c = master chain code
429 # n = index of key we want to derive
430 # This function allows us to find the nth public key, as long as n is
431 # non-negative. If n is negative, we need the master private key to find it.
432 def CKD_prime(K, c, n):
434 from ecdsa.util import string_to_number, number_to_string
435 order = generator_secp256k1.order()
437 if n & BIP32_PRIME: raise
439 K_public_key = ecdsa.VerifyingKey.from_string( K, curve = SECP256k1 )
440 K_compressed = GetPubKey(K_public_key.pubkey,True)
442 I = hmac.new(c, K_compressed + rev_hex(int_to_hex(n,4)).decode('hex'), hashlib.sha512).digest()
445 pubkey_point = string_to_number(I[0:32])*curve.generator + K_public_key.pubkey.point
446 public_key = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
448 K_n = public_key.to_string()
449 K_n_compressed = GetPubKey(public_key.pubkey,True)
452 return K_n, K_n_compressed, c_n
456 def bip32_private_derivation(k, c, branch, sequence):
457 assert sequence.startswith(branch)
458 sequence = sequence[len(branch):]
459 for n in sequence.split('/'):
461 n = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
463 K, K_compressed = get_pubkeys_from_secret(k)
464 return k.encode('hex'), c.encode('hex'), K.encode('hex'), K_compressed.encode('hex')
467 def bip32_public_derivation(c, K, branch, sequence):
468 assert sequence.startswith(branch)
469 sequence = sequence[len(branch):]
470 for n in sequence.split('/'):
472 K, cK, c = CKD_prime(K, c, n)
474 return c.encode('hex'), K.encode('hex'), cK.encode('hex')
477 def bip32_private_key(sequence, k, chain):
479 k, chain = CKD(k, chain, i)
480 return SecretToASecret(k, True)
485 ################################## transactions
487 MIN_RELAY_TX_FEE = 10000
491 def test_bip32(seed, sequence):
494 see https://en.bitcoin.it/wiki/BIP_0032_TestVectors
497 master_secret, master_chain, master_public_key, master_public_key_compressed = bip32_init(seed)
499 print "secret key", master_secret.encode('hex')
500 print "chain code", master_chain.encode('hex')
502 key_id = hash_160(master_public_key_compressed)
503 print "keyid", key_id.encode('hex')
505 print "address", hash_160_to_bc_address(key_id)
506 print "secret key", SecretToASecret(master_secret, True)
512 for n in sequence.split('/'):
514 print "Chain [%s]" % '/'.join(s)
516 n = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
517 k0, c0 = CKD(k, c, n)
518 K0, K0_compressed = get_pubkeys_from_secret(k0)
521 print " * (main addr)", hash_160_to_bc_address(hash_160(K0_compressed))
524 print " * (hex)", k0.encode('hex')
525 print " * (wif)", SecretToASecret(k0, True)
528 print " * (hex)", c0.encode('hex')
537 if __name__ == '__main__':
538 test_bip32("000102030405060708090a0b0c0d0e0f", "0'/1/2'/2/1000000000")
539 test_bip32("fffcf9f6f3f0edeae7e4e1dedbd8d5d2cfccc9c6c3c0bdbab7b4b1aeaba8a5a29f9c999693908d8a8784817e7b7875726f6c696663605d5a5754514e4b484542","0/2147483647'/1/2147483646'/2")