import binascii from random import choice from . import sm3, func from Cryptodome.Util.asn1 import DerSequence, DerInteger from binascii import unhexlify # 选择素域，设置椭圆曲线参数 default_ecc_table = { 'n': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFF7203DF6B21C6052B53BBF40939D54123', 'p': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF', 'g': '32c4ae2c1f1981195f9904466a39c9948fe30bbff2660be1715a4589334c74c7' 'bc3736a2f4f6779c59bdcee36b692153d0a9877cc62a474002df32e52139f0a0', 'a': 'FFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC', 'b': '28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93', } class CryptSM2(object): def __init__(self, private_key, public_key, ecc_table=default_ecc_table, mode=0, asn1=False, decmode=0): """ mode: 0-C1C2C3, 1-C1C3C2 (default is 1) """ self.private_key = private_key self.public_key = public_key.lstrip("04") if public_key.startswith("04") else public_key self.para_len = len(ecc_table['n']) self.ecc_a3 = ( int(ecc_table['a'], base=16) + 3) % int(ecc_table['p'], base=16) self.ecc_table = ecc_table assert mode in (0, 1), 'mode must be one of (0, 1)' self.mode = mode self.asn1 = asn1 self.decmode = decmode def _kg(self, k, Point): # kP运算 Point = '%s%s' % (Point, '1') mask_str = '8' for i in range(self.para_len - 1): mask_str += '0' mask = int(mask_str, 16) Temp = Point flag = False for n in range(self.para_len * 4): if (flag): Temp = self._double_point(Temp) if (k & mask) != 0: if (flag): Temp = self._add_point(Temp, Point) else: flag = True Temp = Point k = k << 1 return self._convert_jacb_to_nor(Temp) def _double_point(self, Point): # 倍点 l = len(Point) len_2 = 2 * self.para_len if l < self.para_len * 2: return None else: x1 = int(Point[0:self.para_len], 16) y1 = int(Point[self.para_len:len_2], 16) if l == len_2: z1 = 1 else: z1 = int(Point[len_2:], 16) T6 = (z1 * z1) % int(self.ecc_table['p'], base=16) T2 = (y1 * y1) % int(self.ecc_table['p'], base=16) T3 = (x1 + T6) % int(self.ecc_table['p'], base=16) T4 = (x1 - T6) % int(self.ecc_table['p'], base=16) T1 = (T3 * T4) % int(self.ecc_table['p'], base=16) T3 = (y1 * z1) % int(self.ecc_table['p'], base=16) T4 = (T2 * 8) % int(self.ecc_table['p'], base=16) T5 = (x1 * T4) % int(self.ecc_table['p'], base=16) T1 = (T1 * 3) % int(self.ecc_table['p'], base=16) T6 = (T6 * T6) % int(self.ecc_table['p'], base=16) T6 = (self.ecc_a3 * T6) % int(self.ecc_table['p'], base=16) T1 = (T1 + T6) % int(self.ecc_table['p'], base=16) z3 = (T3 + T3) % int(self.ecc_table['p'], base=16) T3 = (T1 * T1) % int(self.ecc_table['p'], base=16) T2 = (T2 * T4) % int(self.ecc_table['p'], base=16) x3 = (T3 - T5) % int(self.ecc_table['p'], base=16) if (T5 % 2) == 1: T4 = (T5 + ((T5 + int(self.ecc_table['p'], base=16)) >> 1) - T3) % int( self.ecc_table['p'], base=16) else: T4 = (T5 + (T5 >> 1) - T3) % int(self.ecc_table['p'], base=16) T1 = (T1 * T4) % int(self.ecc_table['p'], base=16) y3 = (T1 - T2) % int(self.ecc_table['p'], base=16) form = '%%0%dx' % self.para_len form = form * 3 return form % (x3, y3, z3) def _add_point(self, P1, P2): # 点加函数，P2点为仿射坐标即z=1，P1为Jacobian加重射影坐标 len_2 = 2 * self.para_len l1 = len(P1) l2 = len(P2) if (l1 < len_2) or (l2 < len_2): return None else: X1 = int(P1[0:self.para_len], 16) Y1 = int(P1[self.para_len:len_2], 16) if (l1 == len_2): Z1 = 1 else: Z1 = int(P1[len_2:], 16) x2 = int(P2[0:self.para_len], 16) y2 = int(P2[self.para_len:len_2], 16) T1 = (Z1 * Z1) % int(self.ecc_table['p'], base=16) T2 = (y2 * Z1) % int(self.ecc_table['p'], base=16) T3 = (x2 * T1) % int(self.ecc_table['p'], base=16) T1 = (T1 * T2) % int(self.ecc_table['p'], base=16) T2 = (T3 - X1) % int(self.ecc_table['p'], base=16) T3 = (T3 + X1) % int(self.ecc_table['p'], base=16) T4 = (T2 * T2) % int(self.ecc_table['p'], base=16) T1 = (T1 - Y1) % int(self.ecc_table['p'], base=16) Z3 = (Z1 * T2) % int(self.ecc_table['p'], base=16) T2 = (T2 * T4) % int(self.ecc_table['p'], base=16) T3 = (T3 * T4) % int(self.ecc_table['p'], base=16) T5 = (T1 * T1) % int(self.ecc_table['p'], base=16) T4 = (X1 * T4) % int(self.ecc_table['p'], base=16) X3 = (T5 - T3) % int(self.ecc_table['p'], base=16) T2 = (Y1 * T2) % int(self.ecc_table['p'], base=16) T3 = (T4 - X3) % int(self.ecc_table['p'], base=16) T1 = (T1 * T3) % int(self.ecc_table['p'], base=16) Y3 = (T1 - T2) % int(self.ecc_table['p'], base=16) form = '%%0%dx' % self.para_len form = form * 3 return form % (X3, Y3, Z3) def _convert_jacb_to_nor(self, Point): # Jacobian加重射影坐标转换成仿射坐标 len_2 = 2 * self.para_len x = int(Point[0:self.para_len], 16) y = int(Point[self.para_len:len_2], 16) z = int(Point[len_2:], 16) z_inv = pow( z, int(self.ecc_table['p'], base=16) - 2, int(self.ecc_table['p'], base=16)) z_invSquar = (z_inv * z_inv) % int(self.ecc_table['p'], base=16) z_invQube = (z_invSquar * z_inv) % int(self.ecc_table['p'], base=16) x_new = (x * z_invSquar) % int(self.ecc_table['p'], base=16) y_new = (y * z_invQube) % int(self.ecc_table['p'], base=16) z_new = (z * z_inv) % int(self.ecc_table['p'], base=16) if z_new == 1: if self.decmode == 1: zuobiaox = hex(x_new) zuobiaoy = hex(y_new) zuobiaox = self.makepadding(zuobiaox) zuobiaoy = self.makepadding(zuobiaoy) return zuobiaox+zuobiaoy else: form = '%%0%dx' % self.para_len form = form * 2 return form % (x_new, y_new) else: return None def makepadding(self,msg): msg = msg[2:] msg = msg.zfill(self.para_len) #print(msg[0]) if msg[0].isalpha() or ord(msg[0]) >= ord('8'): msg = msg.zfill(self.para_len+2) #print('aaaaa') else: msg = msg #print(msg) return msg def verify(self, Sign, data): # 验签函数，sign签名r||s，E消息hash，public_key公钥 if self.asn1: unhex_sign = unhexlify(Sign.encode()) seq_der = DerSequence() origin_sign = seq_der.decode(unhex_sign) r = origin_sign[0] s = origin_sign[1] else: r = int(Sign[0:self.para_len], 16) s = int(Sign[self.para_len:2*self.para_len], 16) e = int(data.hex(), 16) t = (r + s) % int(self.ecc_table['n'], base=16) if t == 0: return 0 P1 = self._kg(s, self.ecc_table['g']) P2 = self._kg(t, self.public_key) # print(P1) # print(P2) if P1 == P2: P1 = '%s%s' % (P1, 1) P1 = self._double_point(P1) else: P1 = '%s%s' % (P1, 1) P1 = self._add_point(P1, P2) P1 = self._convert_jacb_to_nor(P1) x = int(P1[0:self.para_len], 16) return r == ((e + x) % int(self.ecc_table['n'], base=16)) def sign(self, data, K): """ 签名函数, data消息的hash，private_key私钥，K随机数，均为16进制字符串 :param self: :param data: data消息的hash :param K: K随机数 :return: """ E = data.hex() # 消息转化为16进制字符串 e = int(E, 16) d = int(self.private_key, 16) k = int(K, 16) P1 = self._kg(k, self.ecc_table['g']) x = int(P1[0:self.para_len], 16) R = ((e + x) % int(self.ecc_table['n'], base=16)) if R == 0 or R + k == int(self.ecc_table['n'], base=16): return None d_1 = pow( d+1, int(self.ecc_table['n'], base=16) - 2, int(self.ecc_table['n'], base=16)) S = (d_1*(k + R) - R) % int(self.ecc_table['n'], base=16) if S == 0: return None elif self.asn1: return DerSequence([DerInteger(R), DerInteger(S)]).encode().hex() else: return '%064x%064x' % (R, S) def encrypt(self, data): # 加密函数，data消息(bytes) msg = data.hex() # 消息转化为16进制字符串 k = func.random_hex(self.para_len) C1 = self._kg(int(k, 16), self.ecc_table['g']) xy = self._kg(int(k, 16), self.public_key) x2 = xy[0:self.para_len] y2 = xy[self.para_len:2*self.para_len] ml = len(msg) t = sm3.sm3_kdf(xy.encode('utf8'), ml/2) if int(t, 16) == 0: return None else: form = '%%0%dx' % ml C2 = form % (int(msg, 16) ^ int(t, 16)) C3 = sm3.sm3_hash([ i for i in bytes.fromhex('%s%s%s' % (x2, msg, y2)) ]) if self.mode: return bytes.fromhex('%s%s%s' % (C1, C3, C2)) else: return bytes.fromhex('%s%s%s' % (C1, C2, C3)) def decrypt(self, data): # 解密函数，data密文（bytes） data = data.hex() len_2 = 2 * self.para_len len_3 = len_2 + 64 C1 = data[0:len_2] if self.mode: C3 = data[len_2:len_3] C2 = data[len_3:] else: C2 = data[len_2:-64] C3 = data[-64:] xy = self._kg(int(self.private_key, 16), C1) # print('xy = %s' % xy) x2 = xy[0:self.para_len] y2 = xy[self.para_len:len_2] cl = len(C2) t = sm3.sm3_kdf(xy.encode('utf8'), cl/2) if int(t, 16) == 0: return None else: form = '%%0%dx' % cl M = form % (int(C2, 16) ^ int(t, 16)) u = sm3.sm3_hash([ i for i in bytes.fromhex('%s%s%s' % (x2, M, y2)) ]) return bytes.fromhex(M) def decmsg(self, data): # 解密函数，data密文（bytes） data = data.lstrip("04") if data.startswith("04") else data len_2 = 2 * self.para_len #print(self.para_len) len_3 = len_2 + 64 C1 = data[0:len_2] if self.mode: C3 = data[len_2:len_3] C2 = data[len_3:] else: C2 = data[len_2:-64] C3 = data[-64:] xy = self._kg(int(self.private_key, 16), C1) #print('xy = %s' % xy) x2 = xy[0:self.para_len] y2 = xy[self.para_len:len_2] cl = len(C2) t = sm3.sm3_kdf(xy.encode('utf8'), cl/2) if int(t, 16) == 0: return None else: form = '%%0%dx' % cl M = form % (int(C2, 16) ^ int(t, 16)) u = sm3.sm3_hash([ i for i in bytes.fromhex('%s%s%s' % (x2, M, y2)) ]) return bytes.fromhex(M) def _sm3_z(self, data): """ SM3WITHSM2 签名规则: SM2.sign(SM3(Z+MSG)，PrivateKey) 其中: z = Hash256(Len(ID) + ID + a + b + xG + yG + xA + yA) """ # sm3withsm2 的 z 值 z = '0080'+'31323334353637383132333435363738' + \ self.ecc_table['a'] + self.ecc_table['b'] + self.ecc_table['g'] + \ self.public_key z = binascii.a2b_hex(z) Za = sm3.sm3_hash(func.bytes_to_list(z)) M_ = (Za + data.hex()).encode('utf-8') e = sm3.sm3_hash(func.bytes_to_list(binascii.a2b_hex(M_))) return e def sign_with_sm3(self, data, random_hex_str=None): sign_data = binascii.a2b_hex(self._sm3_z(data).encode('utf-8')) if random_hex_str is None: random_hex_str = func.random_hex(self.para_len) sign = self.sign(sign_data, random_hex_str) # 16进制 return sign def verify_with_sm3(self, sign, data): sign_data = binascii.a2b_hex(self._sm3_z(data).encode('utf-8')) return self.verify(sign, sign_data)