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Python Utils.inverse方法代码示例

本文整理汇总了Python中algs.Utils.inverse方法的典型用法代码示例。如果您正苦于以下问题:Python Utils.inverse方法的具体用法?Python Utils.inverse怎么用?Python Utils.inverse使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在algs.Utils的用法示例。


在下文中一共展示了Utils.inverse方法的4个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Python代码示例。

示例1: prove_decryption

# 需要导入模块: from algs import Utils [as 别名]
# 或者: from algs.Utils import inverse [as 别名]
    def prove_decryption(self, ciphertext):
        """
        given g, y, alpha, beta/(encoded m), prove equality of discrete log
        with Chaum Pedersen, and that discrete log is x, the secret key.

        Prover sends a=g^w, b=alpha^w for random w
        Challenge c = sha1(a,b) with and b in decimal form
        Prover sends t = w + xc

        Verifier will check that g^t = a * y^c
        and alpha^t = b * beta/m ^ c
        """
        
        m = (Utils.inverse(pow(ciphertext.alpha, self.x, self.pk.p), self.pk.p) * ciphertext.beta) % self.pk.p
        beta_over_m = (ciphertext.beta * Utils.inverse(m, self.pk.p)) % self.pk.p

        # pick a random w
        w = Utils.random_mpz_lt(self.pk.q)
        a = pow(self.pk.g, w, self.pk.p)
        b = pow(ciphertext.alpha, w, self.pk.p)

        c = int(hashlib.sha1(str(a) + "," + str(b)).hexdigest(),16)

        t = (w + self.x * c) % self.pk.q

        return m, {
            'commitment' : {'A' : str(a), 'B': str(b)},
            'challenge' : str(c),
            'response' : str(t)
          }
开发者ID:mccajm,项目名称:helios-server,代码行数:32,代码来源:elgamal.py

示例2: decrypt

# 需要导入模块: from algs import Utils [as 别名]
# 或者: from algs.Utils import inverse [as 别名]
    def decrypt(self, decryption_factors, public_key):
      """
      decrypt a ciphertext given a list of decryption factors (from multiple trustees)
      For now, no support for threshold
      """
      running_decryption = self.beta
      for dec_factor in decryption_factors:
        running_decryption = (running_decryption * Utils.inverse(dec_factor, public_key.p)) % public_key.p

      return running_decryption
开发者ID:grnet,项目名称:zeus,代码行数:12,代码来源:elgamal.py

示例3: simulate_encryption_proof

# 需要导入模块: from algs import Utils [as 别名]
# 或者: from algs.Utils import inverse [as 别名]
    def simulate_encryption_proof(self, plaintext, challenge=None):
      # generate a random challenge if not provided
      if not challenge:
        challenge = Utils.random_mpz_lt(self.pk.q)

      proof = ZKProof()
      proof.challenge = challenge

      # compute beta/plaintext, the completion of the DH tuple
      beta_over_plaintext =  (self.beta * Utils.inverse(plaintext.m, self.pk.p)) % self.pk.p

      # random response, does not even need to depend on the challenge
      proof.response = Utils.random_mpz_lt(self.pk.q);

      # now we compute A and B
      proof.commitment['A'] = (Utils.inverse(pow(self.alpha, proof.challenge, self.pk.p), self.pk.p) * pow(self.pk.g, proof.response, self.pk.p)) % self.pk.p
      proof.commitment['B'] = (Utils.inverse(pow(beta_over_plaintext, proof.challenge, self.pk.p), self.pk.p) * pow(self.pk.y, proof.response, self.pk.p)) % self.pk.p

      return proof
开发者ID:grnet,项目名称:zeus,代码行数:21,代码来源:elgamal.py

示例4: verify_encryption_proof

# 需要导入模块: from algs import Utils [as 别名]
# 或者: from algs.Utils import inverse [as 别名]
    def verify_encryption_proof(self, plaintext, proof):
      """
      Checks for the DDH tuple g, y, alpha, beta/plaintext.
      (PoK of randomness r.)

      Proof contains commitment = {A, B}, challenge, response
      """

      # check that g^response = A * alpha^challenge
      first_check = (pow(self.pk.g, proof.response, self.pk.p) == ((pow(self.alpha, proof.challenge, self.pk.p) * proof.commitment['A']) % self.pk.p))

      # check that y^response = B * (beta/m)^challenge
      beta_over_m = (self.beta * Utils.inverse(plaintext.m, self.pk.p)) % self.pk.p
      second_check = (pow(self.pk.y, proof.response, self.pk.p) == ((pow(beta_over_m, proof.challenge, self.pk.p) * proof.commitment['B']) % self.pk.p))

      # print "1,2: %s %s " % (first_check, second_check)
      return (first_check and second_check)
开发者ID:grnet,项目名称:zeus,代码行数:19,代码来源:elgamal.py


注:本文中的algs.Utils.inverse方法示例由纯净天空整理自Github/MSDocs等开源代码及文档管理平台,相关代码片段筛选自各路编程大神贡献的开源项目,源码版权归原作者所有,传播和使用请参考对应项目的License;未经允许,请勿转载。