xtrace_sdk.crypto.encryption.paillier_lookup
============================================

.. py:module:: xtrace_sdk.crypto.encryption.paillier_lookup


Attributes
----------

.. autoapisummary::

   xtrace_sdk.crypto.encryption.paillier_lookup.MSG_BITS
   xtrace_sdk.crypto.encryption.paillier_lookup.NOISE_TABLE_SIZE
   xtrace_sdk.crypto.encryption.paillier_lookup.NOISE_MULTIPLES


Classes
-------

.. autoapisummary::

   xtrace_sdk.crypto.encryption.paillier_lookup.Paillier_Lookup


Module Contents
---------------

.. py:data:: MSG_BITS
   :value: 8


.. py:data:: NOISE_TABLE_SIZE
   :value: 256


.. py:data:: NOISE_MULTIPLES
   :value: 14


.. py:class:: Paillier_Lookup(keys)

   Bases: :py:obj:`xtrace_sdk.crypto.encryption.homomorphic_base.HomomorphicBase`\ [\ :py:obj:`int`\ , :py:obj:`int`\ , :py:obj:`xtrace_sdk.utils.xtrace_types.PaillierKeyPair`\ , :py:obj:`xtrace_sdk.utils.xtrace_types.PaillierPublicKey`\ ]


   A self implemented paillier encryption scheme


   .. py:attribute:: keys


   .. py:method:: key_gen(key_len, alpha_len)
      :staticmethod:


      Key generation routine for the Paillier crypto scheme.

      :param key_len: the number of bits in PK SK
      :type key_len: int
      :return: Paillier PK, SK pair
      :rtype: PaillierKeyPair



   .. py:method:: precompute_g_table(g, n, key_len, msg_bits = MSG_BITS)
      :staticmethod:



   .. py:method:: precompute_noise_table(g, n, size = NOISE_TABLE_SIZE)
      :staticmethod:



   .. py:method:: gen_dsa_params_custom(p_bits, q_bits)
      :staticmethod:


      1024-bit DSA => q is 160-bit (FIPS 186-4).

      :param p_bits: The number of bits for the keys
      :type p_bits: int
      :param q_bits: The number of bits in alpha
      :type q_bits: int
      :return: mpz(P), mpz(Q), mpz(G).
      :rtype: int



   .. py:method:: generate_random_r(pk)
      :staticmethod:


      Helper function for encryption required by Paillier scheme

      :param pk: the public key
      :type pk: PaillierPublicKey
      :return: a random r to be used for encryption.
      :rtype: int



   .. py:method:: encrypt(plaintext, pk, g_table = None, noise_table = None, message_chunks = 0)
      :staticmethod:


      Encryption with PK

      :param plaintext: the plaintext to be encrypted.
      :type plaintext: int
      :param pk: the public key to be used for encryption
      :type pk: PaillierPublicKey
      :return: Paillier cipher
      :rtype: int



   .. py:method:: decrypt(ciphertext, keys)
      :staticmethod:


      Decrypts a cihpher with paillier key pair and returns the plaintext

      :param ciphertext: cipher to be decrypted
      :type ciphertext: int
      :param keys: pk,sk pair where sk is used to encrypt ct.
      :type keys: PaillierKeyPair
      :return: plaintext
      :rtype: int



   .. py:method:: add(ciphertext1, ciphertext2, pk)
      :staticmethod:


      Homomorphic addition of Paillier crypto system.

      :param ciphertext1: one the ciphers to be added
      :type ciphertext1: int
      :param ciphertext2:  one the ciphers to be added
      :type ciphertext2: int
      :param pk: Pailier public key
      :type pk: PaillierPublicKey
      :return: ciphertext3 such that decrypt(ct3,sk) = decrypt(ct1,sk) + decrypt(ct2,sk)
      :rtype: int



   .. py:method:: multiply(ciphertext1, ciphertext2, pk)
      :staticmethod:

      :abstractmethod:


      Not supported for Paillier.




   .. py:method:: xor(ciphertext1, ciphertext2, pk)
      :staticmethod:

      :abstractmethod:


      Not supported for Paillier.




   .. py:method:: L(x, n)
      :staticmethod:


      Helper method for decryption




   .. py:method:: bitlen(x)
      :staticmethod:


      Helper method to get bit length of gmpy mpz integers




   .. py:method:: crt_pair(a1, m1, a2, m2)
      :staticmethod:


      Helper method for Chinsese Remainder Theorem




   .. py:method:: lift_to_p2_with_p_component(g_mod_p, p)
      :staticmethod:


      Multiply by (1+p) to inject an order-p component in Z_{p^2}*