Systems and methods for secure linear operations in machine learning via homomorphic aggregates

A system for computing a linear operation of a machine learning model (MLM), comprising:

• at least one memory;
• and
• at least one hardware processor coupled with the at least one memory and configured, individually or in combination, to:
• obtain a weight matrix associated with the linear operation, the weight matrix comprising a plurality of weight elements including a first non-zero value and a second non-zero value that is a negative value;
• decompose the weight matrix into:
• a first binary matrix having elements that indicate positions of the first non-zero value in the weight matrix;
• and
• a second binary matrix having elements that indicate positions of the second non-zero value in the weight matrix;
• encrypt, using an encryption scheme, a plurality of vector elements of an input vector associated with the linear operation to obtain an encrypted input vector;
• for each respective row of the first binary matrix and the second binary matrix, homomorphically process, using the encryption scheme and the first binary matrix and the second binary matrix, encrypted elements of the encrypted input vector selected according to the first binary matrix and the second binary matrix to generate, for the respective row, at least two intermediate encrypted aggregates corresponding to respective contribution signs;
• and
• generate an output element corresponding to the respective row based on a combination of the at least two intermediate encrypted aggregates.

A non-transitory computer readable medium storing thereon computer executable instructions for computing a linear operation of a machine learning model (MLM), including instructions for:

• obtaining a weight matrix associated with the linear operation, the weight matrix comprising a plurality of weight elements including a first non-zero value and a second non-zero value that is a negative value;
• decomposing the weight matrix into:
• a first binary matrix having elements that indicate positions of the first non-zero value in the weight matrix;
• and
• a second binary matrix having elements that indicate positions of the second non-zero value in the weight matrix;
• encrypting, using an encryption scheme, a plurality of vector elements of an input vector associated with the linear operation to obtain an encrypted input vector;
• for each respective row of the first binary matrix and the second binary matrix, homomorphically processing, using the encryption scheme and the first binary matrix and the second binary matrix, encrypted elements of the encrypted input vector selected according to the first binary matrix and the second binary matrix to generate, for the respective row, at least two intermediate encrypted aggregates corresponding to respective contribution signs;
• and
• generating an output element corresponding to the respective row based on a combination of the at least two intermediate encrypted aggregates.