+# -*- coding: utf-8 -*-
#!/usr/bin/env python
#
# Electrum - lightweight Bitcoin client
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
+import hashlib
+import base64
+import re
+import sys
+import hmac
-import hashlib, base64, ecdsa, re
+from util import print_error
+from version import SEED_PREFIX
+
+try:
+ import ecdsa
+except ImportError:
+ sys.exit("Error: python-ecdsa does not seem to be installed. Try 'sudo pip install ecdsa'")
+
+try:
+ import aes
+except ImportError:
+ sys.exit("Error: AES does not seem to be installed. Try 'sudo pip install slowaes'")
+
+################################## transactions
+
+MIN_RELAY_TX_FEE = 1000
+
+
+# AES encryption
+EncodeAES = lambda secret, s: base64.b64encode(aes.encryptData(secret,s))
+DecodeAES = lambda secret, e: aes.decryptData(secret, base64.b64decode(e))
+
+
+def pw_encode(s, password):
+ if password:
+ secret = Hash(password)
+ return EncodeAES(secret, s.encode("utf8"))
+ else:
+ return s
+
+
+def pw_decode(s, password):
+ if password is not None:
+ secret = Hash(password)
+ try:
+ d = DecodeAES(secret, s).decode("utf8")
+ except Exception:
+ raise Exception('Invalid password')
+ return d
+ else:
+ return s
def rev_hex(s):
return s.decode('hex')[::-1].encode('hex')
+
def int_to_hex(i, length=1):
s = hex(i)[2:].rstrip('L')
s = "0"*(2*length - len(s)) + s
return rev_hex(s)
+
def var_int(i):
+ # https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
if i<0xfd:
return int_to_hex(i)
elif i<=0xffff:
return "ff"+int_to_hex(i,8)
-Hash = lambda x: hashlib.sha256(hashlib.sha256(x).digest()).digest()
+def op_push(i):
+ if i<0x4c:
+ return int_to_hex(i)
+ elif i<0xff:
+ return '4c' + int_to_hex(i)
+ elif i<0xffff:
+ return '4d' + int_to_hex(i,2)
+ else:
+ return '4e' + int_to_hex(i,4)
+
+
+def sha256(x):
+ return hashlib.sha256(x).digest()
+
+
+def Hash(x):
+ if type(x) is unicode: x=x.encode('utf-8')
+ return sha256(sha256(x))
+
+
hash_encode = lambda x: x[::-1].encode('hex')
hash_decode = lambda x: x.decode('hex')[::-1]
+hmac_sha_512 = lambda x,y: hmac.new(x, y, hashlib.sha512).digest()
+
+
+def mnemonic_to_seed(mnemonic, passphrase):
+ from pbkdf2 import PBKDF2
+ import hmac
+ PBKDF2_ROUNDS = 2048
+ return PBKDF2(mnemonic, 'mnemonic' + passphrase, iterations = PBKDF2_ROUNDS, macmodule = hmac, digestmodule = hashlib.sha512).read(64)
+
+
+is_new_seed = lambda x: hmac_sha_512("Seed version", x.encode('utf8')).encode('hex')[0:2].startswith(SEED_PREFIX)
+
+def is_old_seed(seed):
+ import mnemonic
+ words = seed.strip().split()
+ try:
+ mnemonic.mn_decode(words)
+ uses_electrum_words = True
+ except Exception:
+ uses_electrum_words = False
+
+ try:
+ seed.decode('hex')
+ is_hex = (len(seed) == 32)
+ except Exception:
+ is_hex = False
+
+ return is_hex or (uses_electrum_words and len(words) == 12)
# pywallet openssl private key implementation
'022100' + \
'%064x' % _r + \
'020101a144034200'
-
- return key.decode('hex') + i2o_ECPublicKey(pkey, compressed)
-
-def i2o_ECPublicKey(pkey, compressed=False):
+
+ return key.decode('hex') + i2o_ECPublicKey(pkey.pubkey, compressed)
+
+def i2o_ECPublicKey(pubkey, compressed=False):
# public keys are 65 bytes long (520 bits)
# 0x04 + 32-byte X-coordinate + 32-byte Y-coordinate
# 0x00 = point at infinity, 0x02 and 0x03 = compressed, 0x04 = uncompressed
# compressed keys: <sign> <x> where <sign> is 0x02 if y is even and 0x03 if y is odd
if compressed:
- if pkey.pubkey.point.y() & 1:
- key = '03' + '%064x' % pkey.pubkey.point.x()
+ if pubkey.point.y() & 1:
+ key = '03' + '%064x' % pubkey.point.x()
else:
- key = '02' + '%064x' % pkey.pubkey.point.x()
+ key = '02' + '%064x' % pubkey.point.x()
else:
key = '04' + \
- '%064x' % pkey.pubkey.point.x() + \
- '%064x' % pkey.pubkey.point.y()
-
+ '%064x' % pubkey.point.x() + \
+ '%064x' % pubkey.point.y()
+
return key.decode('hex')
-
+
# end pywallet openssl private key implementation
-
-
-############ functions from pywallet #####################
-
-addrtype = 0
+
+
+############ functions from pywallet #####################
def hash_160(public_key):
try:
md = hashlib.new('ripemd160')
- md.update(hashlib.sha256(public_key).digest())
+ md.update(sha256(public_key))
return md.digest()
- except:
+ except Exception:
import ripemd
- md = ripemd.new(hashlib.sha256(public_key).digest())
+ md = ripemd.new(sha256(public_key))
return md.digest()
h160 = hash_160(public_key)
return hash_160_to_bc_address(h160)
-def hash_160_to_bc_address(h160):
+def hash_160_to_bc_address(h160, addrtype = 0):
vh160 = chr(addrtype) + h160
h = Hash(vh160)
addr = vh160 + h[0:4]
def bc_address_to_hash_160(addr):
bytes = b58decode(addr, 25)
- return bytes[1:21]
+ return ord(bytes[0]), bytes[1:21]
-def encode_point(pubkey, compressed=False):
- order = generator_secp256k1.order()
- p = pubkey.pubkey.point
- x_str = ecdsa.util.number_to_string(p.x(), order)
- y_str = ecdsa.util.number_to_string(p.y(), order)
- if compressed:
- return chr(2 + (p.y() & 1)) + x_str
- else:
- return chr(4) + pubkey.to_string() #x_str + y_str
__b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
__b58base = len(__b58chars)
+
def b58encode(v):
""" encode v, which is a string of bytes, to base58."""
return (__b58chars[0]*nPad) + result
+
def b58decode(v, length):
""" decode v into a string of len bytes."""
long_value = 0L
hash = Hash(vchIn)
return b58encode(vchIn + hash[0:4])
+
def DecodeBase58Check(psz):
vchRet = b58decode(psz, None)
key = vchRet[0:-4]
else:
return key
+
def PrivKeyToSecret(privkey):
return privkey[9:9+32]
-def SecretToASecret(secret, compressed=False):
+
+def SecretToASecret(secret, compressed=False, addrtype=0):
vchIn = chr((addrtype+128)&255) + secret
if compressed: vchIn += '\01'
return EncodeBase58Check(vchIn)
-def ASecretToSecret(key):
+def ASecretToSecret(key, addrtype=0):
vch = DecodeBase58Check(key)
if vch and vch[0] == chr((addrtype+128)&255):
return vch[1:]
if not b:
return False
b = b[0:32]
- secret = int('0x' + b.encode('hex'), 16)
- return EC_KEY(secret)
+ return EC_KEY(b)
+
+
+def GetPubKey(pubkey, compressed=False):
+ return i2o_ECPublicKey(pubkey, compressed)
-def GetPubKey(pkey, compressed=False):
- return i2o_ECPublicKey(pkey, compressed)
def GetPrivKey(pkey, compressed=False):
return i2d_ECPrivateKey(pkey, compressed)
+
def GetSecret(pkey):
return ('%064x' % pkey.secret).decode('hex')
+
def is_compressed(sec):
b = ASecretToSecret(sec)
return len(b) == 33
+
+def public_key_from_private_key(sec):
+ # rebuild public key from private key, compressed or uncompressed
+ pkey = regenerate_key(sec)
+ assert pkey
+ compressed = is_compressed(sec)
+ public_key = GetPubKey(pkey.pubkey, compressed)
+ return public_key.encode('hex')
+
+
+def address_from_private_key(sec):
+ public_key = public_key_from_private_key(sec)
+ address = public_key_to_bc_address(public_key.decode('hex'))
+ return address
+
+
+def is_valid(addr):
+ return is_address(addr)
+
+
+def is_address(addr):
+ ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
+ if not ADDRESS_RE.match(addr): return False
+ try:
+ addrtype, h = bc_address_to_hash_160(addr)
+ except Exception:
+ return False
+ return addr == hash_160_to_bc_address(h, addrtype)
+
+
+def is_private_key(key):
+ try:
+ k = ASecretToSecret(key)
+ return k is not False
+ except:
+ return False
+
+
########### end pywallet functions #######################
-# secp256k1, http://www.oid-info.com/get/1.3.132.0.10
-_p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2FL
-_r = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141L
-_b = 0x0000000000000000000000000000000000000000000000000000000000000007L
-_a = 0x0000000000000000000000000000000000000000000000000000000000000000L
-_Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798L
-_Gy = 0x483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8L
-curve_secp256k1 = ecdsa.ellipticcurve.CurveFp( _p, _a, _b )
-generator_secp256k1 = ecdsa.ellipticcurve.Point( curve_secp256k1, _Gx, _Gy, _r )
-oid_secp256k1 = (1,3,132,0,10)
-SECP256k1 = ecdsa.curves.Curve("SECP256k1", curve_secp256k1, generator_secp256k1, oid_secp256k1 )
+try:
+ from ecdsa.ecdsa import curve_secp256k1, generator_secp256k1
+except Exception:
+ print "cannot import ecdsa.curve_secp256k1. You probably need to upgrade ecdsa.\nTry: sudo pip install --upgrade ecdsa"
+ exit()
+
+from ecdsa.curves import SECP256k1
+from ecdsa.ellipticcurve import Point
+from ecdsa.util import string_to_number, number_to_string
+
+def msg_magic(message):
+ varint = var_int(len(message))
+ encoded_varint = "".join([chr(int(varint[i:i+2], 16)) for i in xrange(0, len(varint), 2)])
+ return "\x18Bitcoin Signed Message:\n" + encoded_varint + message
+
+
+def verify_message(address, signature, message):
+ try:
+ EC_KEY.verify_message(address, signature, message)
+ return True
+ except Exception as e:
+ print_error("Verification error: {0}".format(e))
+ return False
+
+
+def encrypt_message(message, pubkey):
+ return EC_KEY.encrypt_message(message, pubkey.decode('hex'))
+
+
+def chunks(l, n):
+ return [l[i:i+n] for i in xrange(0, len(l), n)]
+
+
+def ECC_YfromX(x,curved=curve_secp256k1, odd=True):
+ _p = curved.p()
+ _a = curved.a()
+ _b = curved.b()
+ for offset in range(128):
+ Mx = x + offset
+ My2 = pow(Mx, 3, _p) + _a * pow(Mx, 2, _p) + _b % _p
+ My = pow(My2, (_p+1)/4, _p )
+
+ if curved.contains_point(Mx,My):
+ if odd == bool(My&1):
+ return [My,offset]
+ return [_p-My,offset]
+ raise Exception('ECC_YfromX: No Y found')
+
+
+def negative_point(P):
+ return Point( P.curve(), P.x(), -P.y(), P.order() )
+
+
+def point_to_ser(P, comp=True ):
+ if comp:
+ return ( ('%02x'%(2+(P.y()&1)))+('%064x'%P.x()) ).decode('hex')
+ return ( '04'+('%064x'%P.x())+('%064x'%P.y()) ).decode('hex')
+
+
+def ser_to_point(Aser):
+ curve = curve_secp256k1
+ generator = generator_secp256k1
+ _r = generator.order()
+ assert Aser[0] in ['\x02','\x03','\x04']
+ if Aser[0] == '\x04':
+ return Point( curve, string_to_number(Aser[1:33]), string_to_number(Aser[33:]), _r )
+ Mx = string_to_number(Aser[1:])
+ return Point( curve, Mx, ECC_YfromX(Mx, curve, Aser[0]=='\x03')[0], _r )
+
+
+
+class MyVerifyingKey(ecdsa.VerifyingKey):
+ @classmethod
+ def from_signature(klass, sig, recid, h, curve):
+ """ See http://www.secg.org/download/aid-780/sec1-v2.pdf, chapter 4.1.6 """
+ from ecdsa import util, numbertheory
+ import msqr
+ curveFp = curve.curve
+ G = curve.generator
+ order = G.order()
+ # extract r,s from signature
+ r, s = util.sigdecode_string(sig, order)
+ # 1.1
+ x = r + (recid/2) * order
+ # 1.3
+ alpha = ( x * x * x + curveFp.a() * x + curveFp.b() ) % curveFp.p()
+ beta = msqr.modular_sqrt(alpha, curveFp.p())
+ y = beta if (beta - recid) % 2 == 0 else curveFp.p() - beta
+ # 1.4 the constructor checks that nR is at infinity
+ R = Point(curveFp, x, y, order)
+ # 1.5 compute e from message:
+ e = string_to_number(h)
+ minus_e = -e % order
+ # 1.6 compute Q = r^-1 (sR - eG)
+ inv_r = numbertheory.inverse_mod(r,order)
+ Q = inv_r * ( s * R + minus_e * G )
+ return klass.from_public_point( Q, curve )
+
class EC_KEY(object):
- def __init__( self, secret ):
+ def __init__( self, k ):
+ secret = string_to_number(k)
self.pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, generator_secp256k1 * secret )
self.privkey = ecdsa.ecdsa.Private_key( self.pubkey, secret )
self.secret = secret
-
-
-
-def filter(s):
- out = re.sub('( [^\n]*|)\n','',s)
- out = out.replace(' ','')
- out = out.replace('\n','')
- return out
-
-# https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
-def raw_tx( inputs, outputs, for_sig = None ):
- s = int_to_hex(1,4) + ' version\n'
- s += var_int( len(inputs) ) + ' number of inputs\n'
- for i in range(len(inputs)):
- _, _, p_hash, p_index, p_script, pubkey, sig = inputs[i]
- s += p_hash.decode('hex')[::-1].encode('hex') + ' prev hash\n'
- s += int_to_hex(p_index,4) + ' prev index\n'
- if for_sig is None:
- sig = sig + chr(1) # hashtype
- script = int_to_hex( len(sig)) + ' push %d bytes\n'%len(sig)
- script += sig.encode('hex') + ' sig\n'
- script += int_to_hex( len(pubkey)) + ' push %d bytes\n'%len(pubkey)
- script += pubkey.encode('hex') + ' pubkey\n'
- elif for_sig==i:
- script = p_script + ' scriptsig \n'
+
+ def get_public_key(self, compressed=True):
+ return point_to_ser(self.pubkey.point, compressed).encode('hex')
+
+ def sign_message(self, message, compressed, address):
+ private_key = ecdsa.SigningKey.from_secret_exponent( self.secret, curve = SECP256k1 )
+ public_key = private_key.get_verifying_key()
+ signature = private_key.sign_digest_deterministic( Hash( msg_magic(message) ), hashfunc=hashlib.sha256, sigencode = ecdsa.util.sigencode_string )
+ assert public_key.verify_digest( signature, Hash( msg_magic(message) ), sigdecode = ecdsa.util.sigdecode_string)
+ for i in range(4):
+ sig = base64.b64encode( chr(27 + i + (4 if compressed else 0)) + signature )
+ try:
+ self.verify_message( address, sig, message)
+ return sig
+ except Exception:
+ continue
+ else:
+ raise Exception("error: cannot sign message")
+
+
+ @classmethod
+ def verify_message(self, address, signature, message):
+ sig = base64.b64decode(signature)
+ if len(sig) != 65: raise Exception("Wrong encoding")
+
+ nV = ord(sig[0])
+ if nV < 27 or nV >= 35:
+ raise Exception("Bad encoding")
+ if nV >= 31:
+ compressed = True
+ nV -= 4
else:
- script=''
- s += var_int( len(filter(script))/2 ) + ' script length \n'
- s += script
- s += "ffffffff" + ' sequence\n'
- s += var_int( len(outputs) ) + ' number of outputs\n'
- for output in outputs:
- addr, amount = output
- s += int_to_hex( amount, 8) + ' amount: %d\n'%amount
- script = '76a9' # op_dup, op_hash_160
- script += '14' # push 0x14 bytes
- script += bc_address_to_hash_160(addr).encode('hex')
- script += '88ac' # op_equalverify, op_checksig
- s += var_int( len(filter(script))/2 ) + ' script length \n'
- s += script + ' script \n'
- s += int_to_hex(0,4) # lock time
- if for_sig is not None: s += int_to_hex(1, 4) # hash type
- return s
+ compressed = False
+
+ recid = nV - 27
+ h = Hash( msg_magic(message) )
+ public_key = MyVerifyingKey.from_signature( sig[1:], recid, h, curve = SECP256k1 )
+
+ # check public key
+ public_key.verify_digest( sig[1:], h, sigdecode = ecdsa.util.sigdecode_string)
+
+ # check that we get the original signing address
+ addr = public_key_to_bc_address( point_to_ser(public_key.pubkey.point, compressed) )
+ if address != addr:
+ raise Exception("Bad signature")
+
+
+ # ecies encryption/decryption methods; aes-256-cbc is used as the cipher; hmac-sha256 is used as the mac
+
+ @classmethod
+ def encrypt_message(self, message, pubkey):
+
+ pk = ser_to_point(pubkey)
+ if not ecdsa.ecdsa.point_is_valid(generator_secp256k1, pk.x(), pk.y()):
+ raise Exception('invalid pubkey')
+
+ ephemeral_exponent = number_to_string(ecdsa.util.randrange(pow(2,256)), generator_secp256k1.order())
+ ephemeral = EC_KEY(ephemeral_exponent)
+
+ ecdh_key = (pk * ephemeral.privkey.secret_multiplier).x()
+ ecdh_key = ('%064x' % ecdh_key).decode('hex')
+ key = hashlib.sha512(ecdh_key).digest()
+ key_e, key_m = key[:32], key[32:]
+
+ iv_ciphertext = aes.encryptData(key_e, message)
+
+ ephemeral_pubkey = ephemeral.get_public_key(compressed=True).decode('hex')
+ encrypted = 'BIE1' + ephemeral_pubkey + iv_ciphertext
+ mac = hmac.new(key_m, encrypted, hashlib.sha256).digest()
+
+ return base64.b64encode(encrypted + mac)
+
+
+ def decrypt_message(self, encrypted):
+
+ encrypted = base64.b64decode(encrypted)
+
+ if len(encrypted) < 85:
+ raise Exception('invalid ciphertext: length')
+ magic = encrypted[:4]
+ ephemeral_pubkey = encrypted[4:37]
+ iv_ciphertext = encrypted[37:-32]
+ mac = encrypted[-32:]
+ if magic != 'BIE1':
+ raise Exception('invalid ciphertext: invalid magic bytes')
+
+ try:
+ ephemeral_pubkey = ser_to_point(ephemeral_pubkey)
+ except AssertionError, e:
+ raise Exception('invalid ciphertext: invalid ephemeral pubkey')
+
+ if not ecdsa.ecdsa.point_is_valid(generator_secp256k1, ephemeral_pubkey.x(), ephemeral_pubkey.y()):
+ raise Exception('invalid ciphertext: invalid ephemeral pubkey')
+
+ ecdh_key = (ephemeral_pubkey * self.privkey.secret_multiplier).x()
+ ecdh_key = ('%064x' % ecdh_key).decode('hex')
+ key = hashlib.sha512(ecdh_key).digest()
+ key_e, key_m = key[:32], key[32:]
+ if mac != hmac.new(key_m, encrypted[:-32], hashlib.sha256).digest():
+ raise Exception('invalid ciphertext: invalid mac')
+
+ return aes.decryptData(key_e, iv_ciphertext)
+
+
+###################################### BIP32 ##############################
+
+random_seed = lambda n: "%032x"%ecdsa.util.randrange( pow(2,n) )
+BIP32_PRIME = 0x80000000
+
+
+def get_pubkeys_from_secret(secret):
+ # public key
+ private_key = ecdsa.SigningKey.from_string( secret, curve = SECP256k1 )
+ public_key = private_key.get_verifying_key()
+ K = public_key.to_string()
+ K_compressed = GetPubKey(public_key.pubkey,True)
+ return K, K_compressed
+
+
+# Child private key derivation function (from master private key)
+# k = master private key (32 bytes)
+# c = master chain code (extra entropy for key derivation) (32 bytes)
+# n = the index of the key we want to derive. (only 32 bits will be used)
+# If n is negative (i.e. the 32nd bit is set), the resulting private key's
+# corresponding public key can NOT be determined without the master private key.
+# However, if n is positive, the resulting private key's corresponding
+# public key can be determined without the master private key.
+def CKD_priv(k, c, n):
+ is_prime = n & BIP32_PRIME
+ return _CKD_priv(k, c, rev_hex(int_to_hex(n,4)).decode('hex'), is_prime)
+
+def _CKD_priv(k, c, s, is_prime):
+ import hmac
+ from ecdsa.util import string_to_number, number_to_string
+ order = generator_secp256k1.order()
+ keypair = EC_KEY(k)
+ cK = GetPubKey(keypair.pubkey,True)
+ data = chr(0) + k + s if is_prime else cK + s
+ I = hmac.new(c, data, hashlib.sha512).digest()
+ k_n = number_to_string( (string_to_number(I[0:32]) + string_to_number(k)) % order , order )
+ c_n = I[32:]
+ return k_n, c_n
+
+# Child public key derivation function (from public key only)
+# K = master public key
+# c = master chain code
+# n = index of key we want to derive
+# This function allows us to find the nth public key, as long as n is
+# non-negative. If n is negative, we need the master private key to find it.
+def CKD_pub(cK, c, n):
+ if n & BIP32_PRIME: raise
+ return _CKD_pub(cK, c, rev_hex(int_to_hex(n,4)).decode('hex'))
+
+# helper function, callable with arbitrary string
+def _CKD_pub(cK, c, s):
+ import hmac
+ from ecdsa.util import string_to_number, number_to_string
+ order = generator_secp256k1.order()
+ I = hmac.new(c, cK + s, hashlib.sha512).digest()
+ curve = SECP256k1
+ pubkey_point = string_to_number(I[0:32])*curve.generator + ser_to_point(cK)
+ public_key = ecdsa.VerifyingKey.from_public_point( pubkey_point, curve = SECP256k1 )
+ c_n = I[32:]
+ cK_n = GetPubKey(public_key.pubkey,True)
+ return cK_n, c_n
+
+
+BITCOIN_HEADERS = ["0488ade4", "0488b21e"]
+TESTNET_HEADERS = ["043587cf", "04358394"]
+
+BITCOIN_HEAD = "0488ade4"
+TESTNET_HEAD = "04358394"
+
+BITCOIN_HEADER_PRIV = "0488ADE4"
+BITCOIN_HEADER_PUB = "0488B21E"
+
+TESTNET_HEADER_PRIV = "04358394"
+TESTNET_HEADER_PUB = "043587CF"
+
+
+def _get_headers(testnet):
+ """Returns the correct headers for either testnet or bitcoin, in the form
+ of a 2-tuple, like (public, private)."""
+ if testnet:
+ return (TESTNET_HEADER_PUB, TESTNET_HEADER_PRIV)
+ else:
+ return (BITCOIN_HEADER_PUB, BITCOIN_HEADER_PRIV)
+
+
+def deserialize_xkey(xkey):
+
+ xkey = DecodeBase58Check(xkey)
+ assert len(xkey) == 78
+
+ xkey_header = xkey[0:4].encode('hex')
+ # Determine if the key is a bitcoin key or a testnet key.
+ if xkey_header in TESTNET_HEADERS:
+ head = TESTNET_HEAD
+ elif xkey_header in BITCOIN_HEADERS:
+ head = BITCOIN_HEAD
+ else:
+ raise Exception("Unknown xkey header: '%s'" % xkey_header)
+
+ depth = ord(xkey[4])
+ fingerprint = xkey[5:9]
+ child_number = xkey[9:13]
+ c = xkey[13:13+32]
+ if xkey[0:4].encode('hex') == head:
+ K_or_k = xkey[13+33:]
+ else:
+ K_or_k = xkey[13+32:]
+ return depth, fingerprint, child_number, c, K_or_k
+
+
+def get_xkey_name(xkey, testnet=False):
+ depth, fingerprint, child_number, c, K = deserialize_xkey(xkey)
+ n = int(child_number.encode('hex'), 16)
+ if n & BIP32_PRIME:
+ child_id = "%d'"%(n - BIP32_PRIME)
+ else:
+ child_id = "%d"%n
+ if depth == 0:
+ return ''
+ elif depth == 1:
+ return child_id
+ else:
+ raise BaseException("xpub depth error")
+
+
+def xpub_from_xprv(xprv, testnet=False):
+ depth, fingerprint, child_number, c, k = deserialize_xkey(xprv)
+ K, cK = get_pubkeys_from_secret(k)
+ header_pub, _ = _get_headers(testnet)
+ xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
+ return EncodeBase58Check(xpub)
+
+
+def bip32_root(seed, testnet=False):
+ import hmac
+ header_pub, header_priv = _get_headers(testnet)
+ seed = seed.decode('hex')
+ I = hmac.new("Bitcoin seed", seed, hashlib.sha512).digest()
+ master_k = I[0:32]
+ master_c = I[32:]
+ K, cK = get_pubkeys_from_secret(master_k)
+ xprv = (header_priv + "00" + "00000000" + "00000000").decode("hex") + master_c + chr(0) + master_k
+ xpub = (header_pub + "00" + "00000000" + "00000000").decode("hex") + master_c + cK
+ return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
+
+
+def bip32_private_derivation(xprv, branch, sequence, testnet=False):
+ header_pub, header_priv = _get_headers(testnet)
+ depth, fingerprint, child_number, c, k = deserialize_xkey(xprv)
+ assert sequence.startswith(branch)
+ sequence = sequence[len(branch):]
+ for n in sequence.split('/'):
+ if n == '': continue
+ i = int(n[:-1]) + BIP32_PRIME if n[-1] == "'" else int(n)
+ parent_k = k
+ k, c = CKD_priv(k, c, i)
+ depth += 1
+
+ _, parent_cK = get_pubkeys_from_secret(parent_k)
+ fingerprint = hash_160(parent_cK)[0:4]
+ child_number = ("%08X"%i).decode('hex')
+ K, cK = get_pubkeys_from_secret(k)
+ xprv = header_priv.decode('hex') + chr(depth) + fingerprint + child_number + c + chr(0) + k
+ xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
+ return EncodeBase58Check(xprv), EncodeBase58Check(xpub)
+
+
+def bip32_public_derivation(xpub, branch, sequence, testnet=False):
+ header_pub, _ = _get_headers(testnet)
+ depth, fingerprint, child_number, c, cK = deserialize_xkey(xpub)
+ assert sequence.startswith(branch)
+ sequence = sequence[len(branch):]
+ for n in sequence.split('/'):
+ if n == '': continue
+ i = int(n)
+ parent_cK = cK
+ cK, c = CKD_pub(cK, c, i)
+ depth += 1
+
+ fingerprint = hash_160(parent_cK)[0:4]
+ child_number = ("%08X"%i).decode('hex')
+ xpub = header_pub.decode('hex') + chr(depth) + fingerprint + child_number + c + cK
+ return EncodeBase58Check(xpub)
+
+
+def bip32_private_key(sequence, k, chain):
+ for i in sequence:
+ k, chain = CKD_priv(k, chain, i)
+ return SecretToASecret(k, True)