ABEncMultiAuth

class ABEncMultiAuth.ABEncMultiAuth

Bases: charm.toolbox.schemebase.SchemeBase

Base class for attribute-based encryption multi-authority

Notes: This class implements an interface for a standard attribute-based encryption scheme.

A public key attribute-based encryption scheme consists of four algorithms: (setup, authsetup, keygen, encrypt, decrypt).

authsetup(gp, object)

Setup an authority. :param gp: The global parameters of the scheme. :param object: Additional required arguments, for example a list of attributes or a name. :return: The result of the authority setup.

decrypt(gp, sk, ct)

Decrypt a ciphertext. :param gp: The global parameters of the scheme. :param sk: The secret keys of the user. :param ct: The ciphertext to decrypt. :return: The plaintext. :raise Exception: Raised when the attributes do not satisfy the access policy.

encrypt(gp, pk, m, object)

Encrypt a message. :param gp: The global parameters of the scheme. :param pk: The public keys of all relevant authorities. :param m: The message to encrypt. :param object: An access policy or a set of attributes to use. :return: The encrypted message.

keygen(gp, sk, gid, object)

Generate user secret keys for attributes from a single authority. :param gp: The global parameters of the scheme. :param sk: The secret keys of the attribute authority. :param gid: Global identifier for the user. :param object: An attribute, list of attributes or access structure, depending on the scheme. :return: The secret keys for the user for the given attributes/access structure.

setup()

Setup this multi-authority attribute based encryption scheme. :return: The result of the central setup, for example some global parameters.