US Patent 10903976 End-to-end secure operations using a query matrix

Systems and methods for an end-to-end secure operation using a query matrix Q_M having dimensions d×s. Exemplary methods include: extracting a set of term components {T} of the operation using a term generation function; partitioning a range of a keyed hash function H(T) into a set of vectors {c_T}; setting Q_M (j,m)=E(B_j,m) when c_T[j]=m for j=0, . . . , (d−1) and for m=0, . . . , (s−1), E(B_j,m) being a non-zero bitmask corresponding to element T from the set of term components {T} encrypted using a homomorphic encryption scheme E; and setting Q_M (j,m)=E(0) when c_T[j]≠m for j=0, . . . , (d−1) and for m=0, . . . , (s−1), E(0) being a zero bitmask encrypted using the homomorphic encryption scheme E.