def generate(self, m):
l, n, seed_len = self.l, self.n, self.seed_len
p, q = PrimeGenerator(10).generate(2048, 224, 256)
g = pow(2, (p - 1) / q, p)
x = rnd.randrange(1, q)
y = pow(g, x, p)
k = rnd.randrange(1, q)
r = pow(g, k, p) % q
s = mul_by_mod(div_by_mod(1, k, q), sha256(m) + x * r, q)
return DSAResult(r, s), p, q, g, y
def is_valid(self, m, p, q, g, y):
if self.r <= 0 or self.r >= q:
return False
if self.s <= 0 or self.s >= q:
return False
w = div_by_mod(1, self.s, q)
u1 = mul_by_mod(sha256(m), w, q)
u2 = mul_by_mod(self.r, w, q)
v = mul_by_mod(pow(g, u1, p), pow(y, u2, p), p) % q
return v == self.r
def generate(self, M):
alpha = sha256(M)
e = alpha % self.ec.n
e = 1 if e == 0 else e
while True:
k = rnd.randrange(1, self.ec.n)
C = k * self.ec.G
r = C.x % self.ec.n
if r == 0:
continue
s = (r * self.d + k * e) % (self.ec.n)
if s == 0:
continue
return r, s
def validate(self, M, r, s):
if r <= 0 or r >= self.ec.n:
return False
if s <= 0 or s >= self.ec.n:
return False
alpha = sha256(M)
e = alpha % self.ec.n
e = 1 if e == 0 else e
v = div_by_mod(1, e, self.ec.n)
z1 = mul_by_mod(s, v, self.ec.n)
z2 = mul_by_mod(-r, v, self.ec.n)
C = z1 * self.ec.G + z2 * self.Q
R = C.x % self.ec.n
return R == r