Python如何实现SM2算法的明文密码加密与解密？

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1. 安装依赖包 pip install gmssl

2.封装SM2加密类 sm2encry.py

from gmssl import sm2 from base64 import b64encode, b64decode

1. 安装依赖包

pip install gmssl

2. 封装类 sm2encry.py

from gmssl import sm2
from base64 import b64encode, b64decode
# sm2的公私钥
SM2_PRIVATE_KEY = '00B9AB0B828FF68872F21A837FC303668428DEA11DCD1B24429D0C99E24EED83D5'
SM2_PUBLIC_KEY = 'B9C9A6E04E9C91F7BA880429273747D7EF5DDEB0BB2FF6317EB00BEF331A83081A6994B8993F3F5D6EADDDB81872266C87C018FB4162F5AF347B483E24620207'

sm2_crypt = sm2.CryptSM2(public_key=SM2_PUBLIC_KEY, private_key=SM2_PRIVATE_KEY)


class sm2Encrypt:
# 加密
def encrypt(self, info):
encode_info = sm2_crypt.encrypt(info.encode(encoding="utf-8"))
encode_info = b64encode(encode_info).decode() # 将二进制bytes通过base64编码
return encode_info

# 解密
def decrypt(self, info):
decode_info = b64decode(info.encode()) # 通过base64解码成二进制bytes
decode_info = sm2_crypt.decrypt(decode_info).decode(encoding="utf-8")
return decode_info


if __name__ == "__main__":
origin_pwd = '123456'
sm2 = sm2Encrypt()
# 加密的密码
encrypy_pwd = sm2.encrypt(origin_pwd)
print(encrypy_pwd)
# 解密的密码
decrypt_pwd = sm2.decrypt(encrypy_pwd)
print(decrypt_pwd)

3. 使用示例（到这一步已经可以完成，第4步是为了生成不同的公私钥）

from sm2encrypy import sm2Encrypy
pass_encrypt = sm2Encrypy()
pwd = pass_encrypt.decrypt("H24OlVZgSTtevCW138O+C5PlZp8OiD920JnpVr7r9ndkGBWFZUVDD48iIVrZRnamgosV5910m9k0438WpIyi0guEt8F5inG7Y5A51whRfdPZ+qdvWVQxI857CBEzkb3h1bMp1ETQ")
print(pwd)

4. 封装类： sm2utils.py (随机生成不同的公私钥)

操作： 执行 python3 sm2utils.py
备注： sm2utils.py内容如下，可以直接照抄

from random import SystemRandom

class CurveFp:
def __init__(self, A, B, P, N, Gx, Gy, name):
self.A = A
self.B = B
self.P = P
self.N = N
self.Gx = Gx
self.Gy = Gy
self.name = name

sm2p256v1 = CurveFp(
name="sm2p256v1",
A=0xFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC,
B=0x28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93,
P=0xFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF,
N=0xFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFF7203DF6B21C6052B53BBF40939D54123,
Gx=0x32C4AE2C1F1981195F9904466A39C9948FE30BBFF2660BE1715A4589334C74C7,
Gy=0xBC3736A2F4F6779C59BDCEE36B692153D0A9877CC62A474002DF32E52139F0A0
)

def multiply(a, n, N, A, P):
return fromJacobian(jacobianMultiply(toJacobian(a), n, N, A, P), P)

def add(a, b, A, P):
return fromJacobian(jacobianAdd(toJacobian(a), toJacobian(b), A, P), P)

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

def toJacobian(Xp_Yp):
Xp, Yp = Xp_Yp
return (Xp, Yp, 1)

def fromJacobian(Xp_Yp_Zp, P):
Xp, Yp, Zp = Xp_Yp_Zp
z = inv(Zp, P)
return ((Xp * z**2) % P, (Yp * z**3) % P)

def jacobianDouble(Xp_Yp_Zp, A, P):
Xp, Yp, Zp = Xp_Yp_Zp
if not Yp:
return (0, 0, 0)
ysq = (Yp ** 2) % P
S = (4 * Xp * ysq) % P
M = (3 * Xp ** 2 + A * Zp ** 4) % P
nx = (M**2 - 2 * S) % P
ny = (M * (S - nx) - 8 * ysq ** 2) % P
nz = (2 * Yp * Zp) % P
return (nx, ny, nz)

def jacobianAdd(Xp_Yp_Zp, Xq_Yq_Zq, A, P):
Xp, Yp, Zp = Xp_Yp_Zp
Xq, Yq, Zq = Xq_Yq_Zq
if not Yp:
return (Xq, Yq, Zq)
if not Yq:
return (Xp, Yp, Zp)
U1 = (Xp * Zq ** 2) % P
U2 = (Xq * Zp ** 2) % P
S1 = (Yp * Zq ** 3) % P
S2 = (Yq * Zp ** 3) % P
if U1 == U2:
if S1 != S2:
return (0, 0, 1)
return jacobianDouble((Xp, Yp, Zp), A, 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 * Zp * Zq) % P
return (nx, ny, nz)

def jacobianMultiply(Xp_Yp_Zp, n, N, A, P):
Xp, Yp, Zp = Xp_Yp_Zp
if Yp == 0 or n == 0:
return (0, 0, 1)
if n == 1:
return (Xp, Yp, Zp)
if n < 0 or n >= N:
return jacobianMultiply((Xp, Yp, Zp), n % N, N, A, P)
if (n % 2) == 0:
return jacobianDouble(jacobianMultiply((Xp, Yp, Zp), n // 2, N, A, P), A, P)
if (n % 2) == 1:
return jacobianAdd(jacobianDouble(jacobianMultiply((Xp, Yp, Zp), n // 2, N, A, P), A, P), (Xp, Yp, Zp), A, P)

class PrivateKey:
def __init__(self, curve=sm2p256v1, secret=None):
self.curve = curve
self.secret = secret or SystemRandom().randrange(1, curve.N)

def publicKey(self):
curve = self.curve
xPublicKey, yPublicKey = multiply((curve.Gx, curve.Gy), self.secret, A=curve.A, P=curve.P, N=curve.N)
return PublicKey(xPublicKey, yPublicKey, curve)

def toString(self):
return "{}".format(str(hex(self.secret))[2:].zfill(64))

class PublicKey:
def __init__(self, x, y, curve):
self.x = x
self.y = y
self.curve = curve

def toString(self, compressed=True):
return {
True: str(hex(self.x))[2:],
False: "{}{}".format(str(hex(self.x))[2:].zfill(64), str(hex(self.y))[2:].zfill(64))
}.get(compressed)


if __name__ == "__main__":
priKey = PrivateKey()
pubKey = priKey.publicKey()
print(priKey.toString())
print(pubKey.toString(compressed = False))