METHOD AND DEVICE FOR CARRYING OUT CRYPTOGRAPHIC COMPUTATION Russian patent published in 2009 - IPC H04L9/06 

FIELD: information technology.

SUBSTANCE: present invention relates to cryptography. The essence of the invention lies in the fact that cryptographic computation is carried out in an electronic component according to a particular cryptographic algorithm, which includes at least one specific nonlinear operation on k-bit data blocks, where k is an integer greater than 2. Several masked intermediate data blocks from j bits (b⊕m, c⊕m2, Δ⊕n) based on the initial data block (a) from k bits are generated, where j is an integer less than k. Then a nonlinear operation S is carried out on at least one j-bit masked intermediate data block (Δ⊕n) with the help of a substitution table (106) with 2^j two inputs, to obtain a j-bit changed data block (S(Δ)⊕n). The changed j-bit data block is joined with at least several of the indicated j-bit masked intermediate data blocks into one final k-bit block (a'), corresponding to the initial k-bit data block, through transformation, which includes the indicated specific nonlinear operation.

EFFECT: reduction in the memory required for encryption.

19 cl, 2 dwg