System and method for providing private inference control

A method for providing private inference control, comprising:

• maintaining a secure database comprising a plurality of records with each record comprising a plurality of attributes;
• specifying a query by encrypting indices identifying one such record and attribute by homomorphic encryption;
• generating a secret key upon reaching a certain query count;
• dividing the secret key into randomly generated key shares and providing a sequence of the key shares, which are each encrypted by homomorphic encryption;
• forming a table of entries by encrypting the indices, the secret key and each of the attributes for each of the records of the database;
• and
• providing the table and decrypting a plurality of the key shares sufficient to recover the secret key subject to a non-inference enabling query.

A system for providing private inference control, comprising:

• a query count and a secure database comprising a plurality of records with each record comprising a plurality of attributes, wherein a set of the attributes form one or more inference channels;
• a regular data structure comprising a set of ciphertext keys, which each relate to one such attribute and record in the secure database;
• a query processor to choose a seed for a pseudorandom function and a secret key for non-malleable encryption;
• a query generator to specify a query by providing indices identifying one such record and attribute and a secure function evaluation circuit to execute a secure function evaluation dependent upon the inference channels, the seed, the secret key, the query count, and the set of ciphertext keys, wherein an output from the secure function evaluation comprises the pseudorandom function and an updated set of ciphertext keys subject to sum-consistency of the set of ciphertext keys and a non-inference enabling query;
• a table of entries formed by combining each of the attributes for each of the records of the database with an output from the pseudorandom function as applied to the seed and the indices, wherein the entry from the table corresponding to the indices is provided.

A method for providing private inference control, comprising:

• maintaining a query count and a secure database comprising a plurality of records with each record comprising a plurality of attributes, wherein a set of the attributes form one or more inference channels;
• constructing a regular data structure comprising a set of ciphertext keys, which each relate to one such attribute and record in the secure database;
• choosing a seed for a pseudorandom function and a secret key for non-malleable encryption;
• specifying a query by providing indices identifying one such record and attribute and executing a secure function evaluation dependent upon the inference channels, the seed, the secret key, the query count, and the set of ciphertext keys;
• generating an output from the secure function evaluation comprising the pseudorandom function and an updated set of ciphertext keys subject to sum-consistency of the set of ciphertext keys and a non-inference enabling query;
• forming a table of entries by combining each of the attributes for each of the records of the database with an output from the pseudorandom function as applied to the seed and the indices;
• and
• providing the entry from the table corresponding to the indices.