```#!/usr/bin/python
from .py2specials import *
from .py3specials import *
import binascii
import hashlib
import re
import sys
import os
import base64
import time
import random
import hmac
from bitcoin.ripemd import *

# Elliptic curve parameters (secp256k1)

P = 2**256 - 2**32 - 977
N = 115792089237316195423570985008687907852837564279074904382605163141518161494337
A = 0
B = 7
Gx = 55066263022277343669578718895168534326250603453777594175500187360389116729240
Gy = 32670510020758816978083085130507043184471273380659243275938904335757337482424
G = (Gx, Gy)

def change_curve(p, n, a, b, gx, gy):
global P, N, A, B, Gx, Gy, G
P, N, A, B, Gx, Gy = p, n, a, b, gx, gy
G = (Gx, Gy)

def getG():
return G

# Extended Euclidean Algorithm

def inv(a, n):
if a == 0:
return 0
lm, hm = 1, 0
low, high = a % n, n
while low > 1:
r = high//low
nm, new = hm-lm*r, high-low*r
lm, low, hm, high = nm, new, lm, low
return lm % n

# JSON access (for pybtctool convenience)

def access(obj, prop):
if isinstance(obj, dict):
if prop in obj:
return obj[prop]
elif '.' in prop:
return obj[float(prop)]
else:
return obj[int(prop)]
else:
return obj[int(prop)]

def multiaccess(obj, prop):
return [access(o, prop) for o in obj]

def slice(obj, start=0, end=2**200):
return obj[int(start):int(end)]

def count(obj):
return len(obj)

_sum = sum

def sum(obj):
return _sum(obj)

def isinf(p):
return p[0] == 0 and p[1] == 0

def to_jacobian(p):
o = (p[0], p[1], 1)
return o

def jacobian_double(p):
if not p[1]:
return (0, 0, 0)
ysq = (p[1] ** 2) % P
S = (4 * p[0] * ysq) % P
M = (3 * p[0] ** 2 + A * p[2] ** 4) % P
nx = (M**2 - 2 * S) % P
ny = (M * (S - nx) - 8 * ysq ** 2) % P
nz = (2 * p[1] * p[2]) % P
return (nx, ny, nz)

if not p[1]:
return q
if not q[1]:
return p
U1 = (p[0] * q[2] ** 2) % P
U2 = (q[0] * p[2] ** 2) % P
S1 = (p[1] * q[2] ** 3) % P
S2 = (q[1] * p[2] ** 3) % P
if U1 == U2:
if S1 != S2:
return (0, 0, 1)
return jacobian_double(p)
H = U2 - U1
R = S2 - S1
H2 = (H * H) % P
H3 = (H * H2) % P
U1H2 = (U1 * H2) % P
nx = (R ** 2 - H3 - 2 * U1H2) % P
ny = (R * (U1H2 - nx) - S1 * H3) % P
nz = (H * p[2] * q[2]) % P
return (nx, ny, nz)

def from_jacobian(p):
z = inv(p[2], P)
return ((p[0] * z**2) % P, (p[1] * z**3) % P)

def jacobian_multiply(a, n):
if a[1] == 0 or n == 0:
return (0, 0, 1)
if n == 1:
return a
if n < 0 or n >= N:
return jacobian_multiply(a, n % N)
if (n % 2) == 0:
return jacobian_double(jacobian_multiply(a, n//2))
if (n % 2) == 1:

def fast_multiply(a, n):
return from_jacobian(jacobian_multiply(to_jacobian(a), n))

# Functions for handling pubkey and privkey formats

def get_pubkey_format(pub):
if is_python2:
two = '\x02'
three = '\x03'
four = '\x04'
else:
two = 2
three = 3
four = 4

if isinstance(pub, (tuple, list)): return 'decimal'
elif len(pub) == 65 and pub[0] == four: return 'bin'
elif len(pub) == 130 and pub[0:2] == '04': return 'hex'
elif len(pub) == 33 and pub[0] in [two, three]: return 'bin_compressed'
elif len(pub) == 66 and pub[0:2] in ['02', '03']: return 'hex_compressed'
elif len(pub) == 64: return 'bin_electrum'
elif len(pub) == 128: return 'hex_electrum'
else: raise Exception("Pubkey not in recognized format")

def encode_pubkey(pub, formt):
if not isinstance(pub, (tuple, list)):
pub = decode_pubkey(pub)
if formt == 'decimal': return pub
elif formt == 'bin': return b'\x04' + encode(pub[0], 256, 32) + encode(pub[1], 256, 32)
elif formt == 'bin_compressed':
return from_int_to_byte(2+(pub[1] % 2)) + encode(pub[0], 256, 32)
elif formt == 'hex': return '04' + encode(pub[0], 16, 64) + encode(pub[1], 16, 64)
elif formt == 'hex_compressed':
return '0'+str(2+(pub[1] % 2)) + encode(pub[0], 16, 64)
elif formt == 'bin_electrum': return encode(pub[0], 256, 32) + encode(pub[1], 256, 32)
elif formt == 'hex_electrum': return encode(pub[0], 16, 64) + encode(pub[1], 16, 64)
else: raise Exception("Invalid format!")

def decode_pubkey(pub, formt=None):
if not formt: formt = get_pubkey_format(pub)
if formt == 'decimal': return pub
elif formt == 'bin': return (decode(pub[1:33], 256), decode(pub[33:65], 256))
elif formt == 'bin_compressed':
x = decode(pub[1:33], 256)
beta = pow(int(x*x*x+A*x+B), int((P+1)//4), int(P))
y = (P-beta) if ((beta + from_byte_to_int(pub[0])) % 2) else beta
return (x, y)
elif formt == 'hex': return (decode(pub[2:66], 16), decode(pub[66:130], 16))
elif formt == 'hex_compressed':
return decode_pubkey(safe_from_hex(pub), 'bin_compressed')
elif formt == 'bin_electrum':
return (decode(pub[:32], 256), decode(pub[32:64], 256))
elif formt == 'hex_electrum':
return (decode(pub[:64], 16), decode(pub[64:128], 16))
else: raise Exception("Invalid format!")

def get_privkey_format(priv):
if isinstance(priv, int_types): return 'decimal'
elif len(priv) == 32: return 'bin'
elif len(priv) == 33: return 'bin_compressed'
elif len(priv) == 64: return 'hex'
elif len(priv) == 66: return 'hex_compressed'
else:
bin_p = b58check_to_bin(priv)
if len(bin_p) == 32: return 'wif'
elif len(bin_p) == 33: return 'wif_compressed'
else: raise Exception("WIF does not represent privkey")

def encode_privkey(priv, formt, vbyte=0):
if not isinstance(priv, int_types):
return encode_privkey(decode_privkey(priv), formt, vbyte)
if formt == 'decimal': return priv
elif formt == 'bin': return encode(priv, 256, 32)
elif formt == 'bin_compressed': return encode(priv, 256, 32)+b'\x01'
elif formt == 'hex': return encode(priv, 16, 64)
elif formt == 'hex_compressed': return encode(priv, 16, 64)+'01'
elif formt == 'wif':
return bin_to_b58check(encode(priv, 256, 32), 128+int(vbyte))
elif formt == 'wif_compressed':
return bin_to_b58check(encode(priv, 256, 32)+b'\x01', 128+int(vbyte))
else: raise Exception("Invalid format!")

def decode_privkey(priv,formt=None):
if not formt: formt = get_privkey_format(priv)
if formt == 'decimal': return priv
elif formt == 'bin': return decode(priv, 256)
elif formt == 'bin_compressed': return decode(priv[:32], 256)
elif formt == 'hex': return decode(priv, 16)
elif formt == 'hex_compressed': return decode(priv[:64], 16)
elif formt == 'wif': return decode(b58check_to_bin(priv),256)
elif formt == 'wif_compressed':
return decode(b58check_to_bin(priv)[:32],256)
else: raise Exception("WIF does not represent privkey")

f1, f2 = get_pubkey_format(p1), get_pubkey_format(p2)
return encode_pubkey(fast_add(decode_pubkey(p1, f1), decode_pubkey(p2, f2)), f1)

f1, f2 = get_privkey_format(p1), get_privkey_format(p2)
return encode_privkey((decode_privkey(p1, f1) + decode_privkey(p2, f2)) % N, f1)

def mul_privkeys(p1, p2):
f1, f2 = get_privkey_format(p1), get_privkey_format(p2)
return encode_privkey((decode_privkey(p1, f1) * decode_privkey(p2, f2)) % N, f1)

def multiply(pubkey, privkey):
f1, f2 = get_pubkey_format(pubkey), get_privkey_format(privkey)
pubkey, privkey = decode_pubkey(pubkey, f1), decode_privkey(privkey, f2)
# http://safecurves.cr.yp.to/twist.html
if not isinf(pubkey) and (pubkey[0]**3+B-pubkey[1]*pubkey[1]) % P != 0:
raise Exception("Point not on curve")
return encode_pubkey(fast_multiply(pubkey, privkey), f1)

def divide(pubkey, privkey):
factor = inv(decode_privkey(privkey), N)
return multiply(pubkey, factor)

def compress(pubkey):
f = get_pubkey_format(pubkey)
if 'compressed' in f: return pubkey
elif f == 'bin': return encode_pubkey(decode_pubkey(pubkey, f), 'bin_compressed')
elif f == 'hex' or f == 'decimal':
return encode_pubkey(decode_pubkey(pubkey, f), 'hex_compressed')

def decompress(pubkey):
f = get_pubkey_format(pubkey)
if 'compressed' not in f: return pubkey
elif f == 'bin_compressed': return encode_pubkey(decode_pubkey(pubkey, f), 'bin')
elif f == 'hex_compressed' or f == 'decimal':
return encode_pubkey(decode_pubkey(pubkey, f), 'hex')

def privkey_to_pubkey(privkey):
f = get_privkey_format(privkey)
privkey = decode_privkey(privkey, f)
if privkey >= N:
raise Exception("Invalid privkey")
if f in ['bin', 'bin_compressed', 'hex', 'hex_compressed', 'decimal']:
return encode_pubkey(fast_multiply(G, privkey), f)
else:
return encode_pubkey(fast_multiply(G, privkey), f.replace('wif', 'hex'))

privtopub = privkey_to_pubkey

def neg_pubkey(pubkey):
f = get_pubkey_format(pubkey)
pubkey = decode_pubkey(pubkey, f)
return encode_pubkey((pubkey[0], (P-pubkey[1]) % P), f)

def neg_privkey(privkey):
f = get_privkey_format(privkey)
privkey = decode_privkey(privkey, f)
return encode_privkey((N - privkey) % N, f)

def subtract_pubkeys(p1, p2):
f1, f2 = get_pubkey_format(p1), get_pubkey_format(p2)
k2 = decode_pubkey(p2, f2)
return encode_pubkey(fast_add(decode_pubkey(p1, f1), (k2[0], (P - k2[1]) % P)), f1)

def subtract_privkeys(p1, p2):
f1, f2 = get_privkey_format(p1), get_privkey_format(p2)
k2 = decode_privkey(p2, f2)
return encode_privkey((decode_privkey(p1, f1) - k2) % N, f1)

# Hashes

def bin_hash160(string):
intermed = hashlib.sha256(string).digest()
digest = ''
try:
digest = hashlib.new('ripemd160', intermed).digest()
except:
digest = RIPEMD160(intermed).digest()
return digest

def hash160(string):
return safe_hexlify(bin_hash160(string))

def bin_sha256(string):
binary_data = string if isinstance(string, bytes) else bytes(string, 'utf-8')
return hashlib.sha256(binary_data).digest()

def sha256(string):
return bytes_to_hex_string(bin_sha256(string))

def bin_ripemd160(string):
try:
digest = hashlib.new('ripemd160', string).digest()
except:
digest = RIPEMD160(string).digest()
return digest

def ripemd160(string):
return safe_hexlify(bin_ripemd160(string))

def bin_dbl_sha256(s):
bytes_to_hash = from_string_to_bytes(s)
return hashlib.sha256(hashlib.sha256(bytes_to_hash).digest()).digest()

def dbl_sha256(string):
return safe_hexlify(bin_dbl_sha256(string))

def bin_slowsha(string):
string = from_string_to_bytes(string)
orig_input = string
for i in range(100000):
string = hashlib.sha256(string + orig_input).digest()
return string

def slowsha(string):
return safe_hexlify(bin_slowsha(string))

def hash_to_int(x):
if len(x) in [40, 64]:
return decode(x, 16)
return decode(x, 256)

def num_to_var_int(x):
x = int(x)
if x < 253: return from_int_to_byte(x)
elif x < 65536: return from_int_to_byte(253)+encode(x, 256, 2)[::-1]
elif x < 4294967296: return from_int_to_byte(254) + encode(x, 256, 4)[::-1]
else: return from_int_to_byte(255) + encode(x, 256, 8)[::-1]

# WTF, Electrum?
def electrum_sig_hash(message):
padded = b"\x18Bitcoin Signed Message:\n" + num_to_var_int(len(message)) + from_string_to_bytes(message)

def random_key():
# Gotta be secure after that java.SecureRandom fiasco...
entropy = random_string(32) \
+ str(random.randrange(2**256)) \
+ str(int(time.time() * 1000000))
return sha256(entropy)

def random_electrum_seed():
entropy = os.urandom(32) \
+ str(random.randrange(2**256)) \
+ str(int(time.time() * 1000000))
return sha256(entropy)[:32]

# Encodings

def b58check_to_bin(inp):
data = b'\x00' * leadingzbytes + changebase(inp, 58, 256)
assert bin_dbl_sha256(data[:-4])[:4] == data[-4:]
return data[1:-4]

def get_version_byte(inp):
data = b'\x00' * leadingzbytes + changebase(inp, 58, 256)
assert bin_dbl_sha256(data[:-4])[:4] == data[-4:]
return ord(data[0])

def hex_to_b58check(inp, magicbyte=0):
return bin_to_b58check(binascii.unhexlify(inp), magicbyte)

def b58check_to_hex(inp):
return safe_hexlify(b58check_to_bin(inp))

if isinstance(pubkey, (list, tuple)):
pubkey = encode_pubkey(pubkey, 'bin')
if len(pubkey) in [66, 130]:
return bin_to_b58check(
bin_hash160(binascii.unhexlify(pubkey)), magicbyte)
return bin_to_b58check(bin_hash160(pubkey), magicbyte)

def is_privkey(priv):
try:
get_privkey_format(priv)
return True
except:
return False

def is_pubkey(pubkey):
try:
get_pubkey_format(pubkey)
return True
except:
return False

# EDCSA

def encode_sig(v, r, s):
vb, rb, sb = from_int_to_byte(v), encode(r, 256), encode(s, 256)

result = base64.b64encode(vb+b'\x00'*(32-len(rb))+rb+b'\x00'*(32-len(sb))+sb)
return result if is_python2 else str(result, 'utf-8')

def decode_sig(sig):
bytez = base64.b64decode(sig)
return from_byte_to_int(bytez[0]), decode(bytez[1:33], 256), decode(bytez[33:], 256)

# https://tools.ietf.org/html/rfc6979#section-3.2

def deterministic_generate_k(msghash, priv):
v = b'\x01' * 32
k = b'\x00' * 32
priv = encode_privkey(priv, 'bin')
msghash = encode(hash_to_int(msghash), 256, 32)
k = hmac.new(k, v+b'\x00'+priv+msghash, hashlib.sha256).digest()
v = hmac.new(k, v, hashlib.sha256).digest()
k = hmac.new(k, v+b'\x01'+priv+msghash, hashlib.sha256).digest()
v = hmac.new(k, v, hashlib.sha256).digest()
return decode(hmac.new(k, v, hashlib.sha256).digest(), 256)

def ecdsa_raw_sign(msghash, priv):

z = hash_to_int(msghash)
k = deterministic_generate_k(msghash, priv)

r, y = fast_multiply(G, k)
s = inv(k, N) * (z + r*decode_privkey(priv)) % N

v, r, s = 27+((y % 2) ^ (0 if s * 2 < N else 1)), r, s if s * 2 < N else N - s
if 'compressed' in get_privkey_format(priv):
v += 4
return v, r, s

def ecdsa_sign(msg, priv):
v, r, s = ecdsa_raw_sign(electrum_sig_hash(msg), priv)
sig = encode_sig(v, r, s)
assert ecdsa_verify(msg, sig,
privtopub(priv)), "Bad Sig!\t %s\nv = %d\n,r = %d\ns = %d" % (sig, v, r, s)
return sig

def ecdsa_raw_verify(msghash, vrs, pub):
v, r, s = vrs
if not (27 <= v <= 34):
return False

w = inv(s, N)
z = hash_to_int(msghash)

u1, u2 = z*w % N, r*w % N
x, y = fast_add(fast_multiply(G, u1), fast_multiply(decode_pubkey(pub), u2))
return bool(r == x and (r % N) and (s % N))

# For BitcoinCore, (msg = addr or msg = "") be default
Q = ecdsa_recover(msg, sig)

def ecdsa_verify(msg, sig, pub):
return ecdsa_raw_verify(electrum_sig_hash(msg), decode_sig(sig), pub)

def ecdsa_raw_recover(msghash, vrs):
v, r, s = vrs
if not (27 <= v <= 34):
raise ValueError("%d must in range 27-31" % v)
x = r
xcubedaxb = (x*x*x+A*x+B) % P
beta = pow(xcubedaxb, (P+1)//4, P)
y = beta if v % 2 ^ beta % 2 else (P - beta)
# If xcubedaxb is not a quadratic residue, then r cannot be the x coord
# for a point on the curve, and so the sig is invalid
if (xcubedaxb - y*y) % P != 0 or not (r % N) or not (s % N):
return False
z = hash_to_int(msghash)
Gz = jacobian_multiply((Gx, Gy, 1), (N - z) % N)
XY = jacobian_multiply((x, y, 1), s)