Cryptanalysis for embedded systems based on electromagnetism emission

Aimed at the DES cryptographic system realized by the P89C668 microcomputer, a experiment is processed by applying a differential electromagnetic analysis method, thereby obtaining 48-bit sub-key of the 16th round of DES. In this essay, the relationship between data in CMOS gate circuits and electromagnetism emission is analyzed, with an EM information leakage model of a register established, and the attack effects of the Hamming weight model and Hamming distance model compared. Based on the test result, EM information leakage exists in CMOS integrated circuit during work, and different instructions have different leakage signatures under two leakage models, thus providing a basis for implementing relevant protective measures for the cryptographic systems.