OPERATOR LIFTING IN CRYPTOGRAPHIC ALGORITHM

摘要

A system for performing an operation on data using obfuscated representations of the data is disclosed. Obtaining means are configured to obtain a first obfuscated representation of a first data value and obtain a second obfuscated representation of a second data value. A determining means 102 is configured to determine an obfuscated representation of a third data value, by performing the corresponding operations on the obfuscated representation of the first data value and the obfuscated representation of the second data value. Obfuscating means 101 may be configured to generate the first obfuscated representation based on the first data value and generate the second obfuscated representation based on the second data value. De-obfuscating means 103 may be configured to de-obfuscate the obfuscated representation of the third data value in order to obtain the third data value using a system of equations.

主权项

1. A system for performing an operation on data using obfuscated representations of the data, comprising:
obtaining means configured to obtain a first obfuscated representation (X0,Y0) of a first data value w0 and obtain a second obfuscated representation (X1,Y1) of a second data value w1, wherein the following relations hold:
X0=A0(w0)⊕B0(σ0)Y0=A1(w0)⊕B1(σ0)X1=A0(w1)⊕B0(σ1)Y1=A1(w1)⊕B1(σ1)wherein
⊕ is an operator, A0 and A1 are linear operators dependent on a data value (w0, w1), B0 and B1 are linear operators dependent on a state variable (σ0, σ1), and an operator E that maps (u,v) to A0(u)⊕B0(v),A1(u)⊕B1(v)), is invertible with respect to u, and σ0 and σ1 are state variables that provide redundancy to the obfuscated representations; and determining means configured to determine an obfuscated representation X2,Y2) of a third data value w2, wherein w2=w0w1, wherein is an operator, by performing the following operations on the obfuscated representation (X0,Y0) of the first data value w0 and the obfuscated representation (X1,Y1) of the second data value w1:
X2=X0⊕X1