794 lines
24 KiB
Python
794 lines
24 KiB
Python
# -*- coding: utf-8 -*-
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#!/usr/bin/env python
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#
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# Electrum - lightweight Bitcoin client
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# Copyright (C) 2011 thomasv@gitorious
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#
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# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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#
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# You should have received a copy of the GNU General Public License
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# along with this program. If not, see <http://www.gnu.org/licenses/>.
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import hashlib
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import base64
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import re
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import sys
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import hmac
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import version
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from util import print_error, InvalidPassword
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try:
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import ecdsa
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except ImportError:
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sys.exit("Error: python-ecdsa does not seem to be installed. Try 'sudo pip install ecdsa'")
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try:
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import aes
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except ImportError:
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sys.exit("Error: AES does not seem to be installed. Try 'sudo pip install slowaes'")
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################################## transactions
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DUST_THRESHOLD = 5430
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MIN_RELAY_TX_FEE = 1000
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RECOMMENDED_FEE = 50000
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COINBASE_MATURITY = 100
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# AES encryption
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EncodeAES = lambda secret, s: base64.b64encode(aes.encryptData(secret,s))
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DecodeAES = lambda secret, e: aes.decryptData(secret, base64.b64decode(e))
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def strip_PKCS7_padding(s):
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"""return s stripped of PKCS7 padding"""
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if len(s)%16 or not s:
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raise ValueError("String of len %d can't be PCKS7-padded" % len(s))
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numpads = ord(s[-1])
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if numpads > 16:
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raise ValueError("String ending with %r can't be PCKS7-padded" % s[-1])
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if s[-numpads:] != numpads*chr(numpads):
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raise ValueError("Invalid PKCS7 padding")
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return s[:-numpads]
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def aes_encrypt_with_iv(key, iv, data):
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mode = aes.AESModeOfOperation.modeOfOperation["CBC"]
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key = map(ord, key)
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iv = map(ord, iv)
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data = aes.append_PKCS7_padding(data)
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keysize = len(key)
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assert keysize in aes.AES.keySize.values(), 'invalid key size: %s' % keysize
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moo = aes.AESModeOfOperation()
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(mode, length, ciph) = moo.encrypt(data, mode, key, keysize, iv)
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return ''.join(map(chr, ciph))
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def aes_decrypt_with_iv(key, iv, data):
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mode = aes.AESModeOfOperation.modeOfOperation["CBC"]
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key = map(ord, key)
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iv = map(ord, iv)
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keysize = len(key)
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assert keysize in aes.AES.keySize.values(), 'invalid key size: %s' % keysize
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data = map(ord, data)
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moo = aes.AESModeOfOperation()
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decr = moo.decrypt(data, None, mode, key, keysize, iv)
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decr = strip_PKCS7_padding(decr)
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return decr
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def pw_encode(s, password):
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if password:
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secret = Hash(password)
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return EncodeAES(secret, s.encode("utf8"))
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else:
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return s
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def pw_decode(s, password):
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if password is not None:
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secret = Hash(password)
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try:
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d = DecodeAES(secret, s).decode("utf8")
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except Exception:
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raise InvalidPassword()
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return d
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else:
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return s
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def rev_hex(s):
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return s.decode('hex')[::-1].encode('hex')
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def int_to_hex(i, length=1):
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s = hex(i)[2:].rstrip('L')
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s = "0"*(2*length - len(s)) + s
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return rev_hex(s)
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def var_int(i):
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# https://en.bitcoin.it/wiki/Protocol_specification#Variable_length_integer
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if i<0xfd:
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return int_to_hex(i)
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elif i<=0xffff:
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return "fd"+int_to_hex(i,2)
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elif i<=0xffffffff:
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return "fe"+int_to_hex(i,4)
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else:
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return "ff"+int_to_hex(i,8)
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def op_push(i):
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if i<0x4c:
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return int_to_hex(i)
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elif i<0xff:
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return '4c' + int_to_hex(i)
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elif i<0xffff:
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return '4d' + int_to_hex(i,2)
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else:
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return '4e' + int_to_hex(i,4)
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def sha256(x):
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return hashlib.sha256(x).digest()
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def Hash(x):
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if type(x) is unicode: x=x.encode('utf-8')
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return sha256(sha256(x))
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hash_encode = lambda x: x[::-1].encode('hex')
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hash_decode = lambda x: x.decode('hex')[::-1]
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hmac_sha_512 = lambda x,y: hmac.new(x, y, hashlib.sha512).digest()
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def is_new_seed(x, prefix=version.SEED_BIP44):
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import mnemonic
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x = mnemonic.prepare_seed(x)
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s = hmac_sha_512("Seed version", x.encode('utf8')).encode('hex')
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return s.startswith(prefix)
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def is_old_seed(seed):
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import old_mnemonic
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words = seed.strip().split()
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try:
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old_mnemonic.mn_decode(words)
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uses_electrum_words = True
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except Exception:
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uses_electrum_words = False
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try:
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seed.decode('hex')
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is_hex = (len(seed) == 32)
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except Exception:
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is_hex = False
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return is_hex or (uses_electrum_words and len(words) == 12)
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# pywallet openssl private key implementation
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def i2d_ECPrivateKey(pkey, compressed=False):
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if compressed:
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key = '3081d30201010420' + \
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'%064x' % pkey.secret + \
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'a081a53081a2020101302c06072a8648ce3d0101022100' + \
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'%064x' % _p + \
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'3006040100040107042102' + \
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'%064x' % _Gx + \
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'022100' + \
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'%064x' % _r + \
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'020101a124032200'
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else:
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key = '308201130201010420' + \
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'%064x' % pkey.secret + \
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'a081a53081a2020101302c06072a8648ce3d0101022100' + \
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'%064x' % _p + \
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'3006040100040107044104' + \
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'%064x' % _Gx + \
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'%064x' % _Gy + \
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'022100' + \
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'%064x' % _r + \
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'020101a144034200'
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return key.decode('hex') + i2o_ECPublicKey(pkey.pubkey, compressed)
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def i2o_ECPublicKey(pubkey, compressed=False):
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# public keys are 65 bytes long (520 bits)
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# 0x04 + 32-byte X-coordinate + 32-byte Y-coordinate
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# 0x00 = point at infinity, 0x02 and 0x03 = compressed, 0x04 = uncompressed
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# compressed keys: <sign> <x> where <sign> is 0x02 if y is even and 0x03 if y is odd
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if compressed:
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if pubkey.point.y() & 1:
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key = '03' + '%064x' % pubkey.point.x()
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else:
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key = '02' + '%064x' % pubkey.point.x()
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else:
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key = '04' + \
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'%064x' % pubkey.point.x() + \
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'%064x' % pubkey.point.y()
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return key.decode('hex')
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# end pywallet openssl private key implementation
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############ functions from pywallet #####################
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def hash_160(public_key):
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try:
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md = hashlib.new('ripemd160')
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md.update(sha256(public_key))
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return md.digest()
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except Exception:
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import ripemd
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md = ripemd.new(sha256(public_key))
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return md.digest()
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def public_key_to_bc_address(public_key):
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h160 = hash_160(public_key)
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return hash_160_to_bc_address(h160)
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def hash_160_to_bc_address(h160, addrtype = 0):
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vh160 = chr(addrtype) + h160
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h = Hash(vh160)
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addr = vh160 + h[0:4]
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return b58encode(addr)
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def bc_address_to_hash_160(addr):
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bytes = b58decode(addr, 25)
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return ord(bytes[0]), bytes[1:21]
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__b58chars = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
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__b58base = len(__b58chars)
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def b58encode(v):
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""" encode v, which is a string of bytes, to base58."""
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long_value = 0L
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for (i, c) in enumerate(v[::-1]):
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long_value += (256**i) * ord(c)
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result = ''
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while long_value >= __b58base:
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div, mod = divmod(long_value, __b58base)
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result = __b58chars[mod] + result
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long_value = div
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result = __b58chars[long_value] + result
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# Bitcoin does a little leading-zero-compression:
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# leading 0-bytes in the input become leading-1s
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nPad = 0
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for c in v:
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if c == '\0': nPad += 1
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else: break
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return (__b58chars[0]*nPad) + result
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def b58decode(v, length):
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""" decode v into a string of len bytes."""
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long_value = 0L
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for (i, c) in enumerate(v[::-1]):
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long_value += __b58chars.find(c) * (__b58base**i)
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result = ''
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while long_value >= 256:
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div, mod = divmod(long_value, 256)
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result = chr(mod) + result
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long_value = div
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result = chr(long_value) + result
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nPad = 0
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for c in v:
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if c == __b58chars[0]: nPad += 1
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else: break
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result = chr(0)*nPad + result
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if length is not None and len(result) != length:
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return None
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return result
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def EncodeBase58Check(vchIn):
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hash = Hash(vchIn)
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return b58encode(vchIn + hash[0:4])
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def DecodeBase58Check(psz):
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vchRet = b58decode(psz, None)
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key = vchRet[0:-4]
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csum = vchRet[-4:]
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hash = Hash(key)
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cs32 = hash[0:4]
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if cs32 != csum:
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return None
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else:
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return key
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def PrivKeyToSecret(privkey):
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return privkey[9:9+32]
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def SecretToASecret(secret, compressed=False, addrtype=0):
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vchIn = chr((addrtype+128)&255) + secret
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if compressed: vchIn += '\01'
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return EncodeBase58Check(vchIn)
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def ASecretToSecret(key, addrtype=0):
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vch = DecodeBase58Check(key)
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if vch and vch[0] == chr((addrtype+128)&255):
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return vch[1:]
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else:
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return False
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def regenerate_key(sec):
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b = ASecretToSecret(sec)
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if not b:
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return False
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b = b[0:32]
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return EC_KEY(b)
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def GetPubKey(pubkey, compressed=False):
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return i2o_ECPublicKey(pubkey, compressed)
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def GetPrivKey(pkey, compressed=False):
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return i2d_ECPrivateKey(pkey, compressed)
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def GetSecret(pkey):
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return ('%064x' % pkey.secret).decode('hex')
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def is_compressed(sec):
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b = ASecretToSecret(sec)
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return len(b) == 33
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def public_key_from_private_key(sec):
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# rebuild public key from private key, compressed or uncompressed
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pkey = regenerate_key(sec)
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assert pkey
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compressed = is_compressed(sec)
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public_key = GetPubKey(pkey.pubkey, compressed)
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return public_key.encode('hex')
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def address_from_private_key(sec):
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public_key = public_key_from_private_key(sec)
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address = public_key_to_bc_address(public_key.decode('hex'))
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return address
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def is_valid(addr):
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return is_address(addr)
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def is_address(addr):
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ADDRESS_RE = re.compile('[1-9A-HJ-NP-Za-km-z]{26,}\\Z')
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if not ADDRESS_RE.match(addr): return False
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try:
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addrtype, h = bc_address_to_hash_160(addr)
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except Exception:
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return False
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return addr == hash_160_to_bc_address(h, addrtype)
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def is_private_key(key):
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try:
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k = ASecretToSecret(key)
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return k is not False
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except:
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return False
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########### end pywallet functions #######################
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try:
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from ecdsa.ecdsa import curve_secp256k1, generator_secp256k1
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except Exception:
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print "cannot import ecdsa.curve_secp256k1. You probably need to upgrade ecdsa.\nTry: sudo pip install --upgrade ecdsa"
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exit()
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from ecdsa.curves import SECP256k1
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from ecdsa.ellipticcurve import Point
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from ecdsa.util import string_to_number, number_to_string
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def msg_magic(message):
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varint = var_int(len(message))
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encoded_varint = "".join([chr(int(varint[i:i+2], 16)) for i in xrange(0, len(varint), 2)])
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return "\x18Bitcoin Signed Message:\n" + encoded_varint + message
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def verify_message(address, signature, message):
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try:
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EC_KEY.verify_message(address, signature, message)
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return True
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except Exception as e:
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print_error("Verification error: {0}".format(e))
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return False
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def encrypt_message(message, pubkey):
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return EC_KEY.encrypt_message(message, pubkey.decode('hex'))
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def chunks(l, n):
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return [l[i:i+n] for i in xrange(0, len(l), n)]
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def ECC_YfromX(x,curved=curve_secp256k1, odd=True):
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_p = curved.p()
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_a = curved.a()
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_b = curved.b()
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for offset in range(128):
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Mx = x + offset
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My2 = pow(Mx, 3, _p) + _a * pow(Mx, 2, _p) + _b % _p
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My = pow(My2, (_p+1)/4, _p )
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if curved.contains_point(Mx,My):
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if odd == bool(My&1):
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return [My,offset]
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return [_p-My,offset]
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raise Exception('ECC_YfromX: No Y found')
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def negative_point(P):
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return Point( P.curve(), P.x(), -P.y(), P.order() )
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def point_to_ser(P, comp=True ):
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if comp:
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return ( ('%02x'%(2+(P.y()&1)))+('%064x'%P.x()) ).decode('hex')
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return ( '04'+('%064x'%P.x())+('%064x'%P.y()) ).decode('hex')
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def ser_to_point(Aser):
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curve = curve_secp256k1
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generator = generator_secp256k1
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_r = generator.order()
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assert Aser[0] in ['\x02','\x03','\x04']
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if Aser[0] == '\x04':
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return Point( curve, string_to_number(Aser[1:33]), string_to_number(Aser[33:]), _r )
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Mx = string_to_number(Aser[1:])
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return Point( curve, Mx, ECC_YfromX(Mx, curve, Aser[0]=='\x03')[0], _r )
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class MyVerifyingKey(ecdsa.VerifyingKey):
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@classmethod
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def from_signature(klass, sig, recid, h, curve):
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""" See http://www.secg.org/download/aid-780/sec1-v2.pdf, chapter 4.1.6 """
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from ecdsa import util, numbertheory
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import msqr
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curveFp = curve.curve
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G = curve.generator
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order = G.order()
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# extract r,s from signature
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r, s = util.sigdecode_string(sig, order)
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# 1.1
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x = r + (recid/2) * order
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# 1.3
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alpha = ( x * x * x + curveFp.a() * x + curveFp.b() ) % curveFp.p()
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beta = msqr.modular_sqrt(alpha, curveFp.p())
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y = beta if (beta - recid) % 2 == 0 else curveFp.p() - beta
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# 1.4 the constructor checks that nR is at infinity
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R = Point(curveFp, x, y, order)
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# 1.5 compute e from message:
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e = string_to_number(h)
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minus_e = -e % order
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# 1.6 compute Q = r^-1 (sR - eG)
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inv_r = numbertheory.inverse_mod(r,order)
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Q = inv_r * ( s * R + minus_e * G )
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return klass.from_public_point( Q, curve )
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class EC_KEY(object):
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def __init__( self, k ):
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secret = string_to_number(k)
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self.pubkey = ecdsa.ecdsa.Public_key( generator_secp256k1, generator_secp256k1 * secret )
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self.privkey = ecdsa.ecdsa.Private_key( self.pubkey, secret )
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self.secret = secret
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def get_public_key(self, compressed=True):
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return point_to_ser(self.pubkey.point, compressed).encode('hex')
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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:
|
|
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-128-CBC with PKCS7 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 = point_to_ser(pk * ephemeral.privkey.secret_multiplier)
|
|
key = hashlib.sha512(ecdh_key).digest()
|
|
iv, key_e, key_m = key[0:16], key[16:32], key[32:]
|
|
ciphertext = aes_encrypt_with_iv(key_e, iv, message)
|
|
ephemeral_pubkey = ephemeral.get_public_key(compressed=True).decode('hex')
|
|
encrypted = 'BIE1' + ephemeral_pubkey + 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]
|
|
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 = point_to_ser(ephemeral_pubkey * self.privkey.secret_multiplier)
|
|
key = hashlib.sha512(ecdh_key).digest()
|
|
iv, key_e, key_m = key[0:16], key[16:32], key[32:]
|
|
if mac != hmac.new(key_m, encrypted[:-32], hashlib.sha256).digest():
|
|
raise Exception('invalid ciphertext: invalid mac')
|
|
|
|
return aes_decrypt_with_iv(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_HEADER_PRIV = "0488ade4"
|
|
BITCOIN_HEADER_PUB = "0488b21e"
|
|
|
|
TESTNET_HEADER_PRIV = "04358394"
|
|
TESTNET_HEADER_PUB = "043587cf"
|
|
|
|
BITCOIN_HEADERS = (BITCOIN_HEADER_PUB, BITCOIN_HEADER_PRIV)
|
|
TESTNET_HEADERS = (TESTNET_HEADER_PUB, TESTNET_HEADER_PRIV)
|
|
|
|
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_HEADERS
|
|
else:
|
|
return BITCOIN_HEADERS
|
|
|
|
|
|
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_HEADER_PRIV
|
|
elif xkey_header in BITCOIN_HEADERS:
|
|
head = BITCOIN_HEADER_PRIV
|
|
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)
|
|
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)
|