def verify_dash_signature(generator, address, message, signature):
compressed = False
G = generator
curve = G.curve()
order = G.order()
_a, _b, _p = curve.a(), curve.b(), curve.p()
sig = base64.b64decode(signature)
if len(sig) != 65:
raise Exception("vmB", "Bad signature")
hb = ord(sig[0])
r, s = map(str_to_long, [sig[1:33], sig[33:65]])
if hb < 27 or hb >= 35:
raise Exception("vmB", "Bad first byte")
if hb >= 31:
compressed = True
hb -= 4
recid = hb - 27
x = (r + (recid / 2) * order) % _p
y2 = (pow(x, 3, _p) + _a * x + _b) % _p
yomy = numbertheory.modular_sqrt(y2, _p)
if (yomy - recid) % 2 == 0:
y = yomy
else:
y = _p - yomy
R = ellipticcurve.Point(curve, x, y, order)
e = str_to_long(message)
minus_e = -e % order
inv_r = numbertheory.inverse_mod(r, order)
Q = inv_r * (R * s + G * minus_e)
key = Key(public_pair=(Q.x(), Q.y()), netcode='DASH')
return key.address(use_uncompressed=not compressed) == address
def uncompress_pubkey(cpk):
'''将压缩版公钥转换为完整版公钥'''
p = 0xFFFFFFFF00000001000000000000000000000000FFFFFFFFFFFFFFFFFFFFFFFF
a = -3
b = 0x5AC635D8AA3A93E7B3EBBD55769886BC651D06B0CC53B0F63BCE3C3E27D2604B
prefix = cpk[:2]
x = int(cpk[2:],16)
y_squared = (x**3 + a*x + b)%p
y = modular_sqrt(y_squared, p)
y_hex = '%x' % y
if (1==int(y_hex[-1],16)%2 and '02' == prefix) or (0==int(y_hex[-1],16)%2 and '03' == prefix):
y = p - y
return '04%064x%064x' % (x,y)
def getFullPubKeyFromCompressed(x_str: str):
prefix = x_str[0:2]
print("prefix = %s" % (prefix))
x_str = x_str[2:]
x = int(x_str, 16)
print("x = \t\t%x" % (x))
p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F
y_squared = (x**3 + 7) % p
y = modular_sqrt(y_squared, p)
y_str = "%x" % y
print("y_str before = \t%s" % (y_str))
y_is_even = (int(y_str[-1], 16) % 2 == 0)
if prefix == "02" and y_is_even == False or prefix == "03" and y_is_even == True:
y = p - y
y_str = "%x" % y
if len(y_str) % 2 == 1:
y_str = "0" + y_str
print("y_str after = \t%s" % (y_str))
return "04" + x_str + y_str