The SMS4 cryptosystem has been used in the Wireless LAN Authentication and Privacy Infrastructure (WAPI) standard for providing data confidentiality in China. So far, reliability has not been considered a primary objective in original version. However, a single fault in the encryption/decryption process can completely change the result of the cryptosystem no matter the natural or malicious injected faults. In this paper, we proposed low-cost structure-independent fault detection scheme for SMS4 cryptosystem which is capable of performing online error detection and can detect a single bit fault or odd multiple bit faults in coverage of 100 percent. Finally, the proposed techniques have been validated on Virtex-7 families FPGA platform to analyze its power consumption, overhead and time delay. It only needs 85 occupied Slices and 8.72mW to run a fault-tolerant scheme of SMS4 cryptosystem with 0.735ns of detection delay. Our new scheme increases in minimum redundancy to enhance cryptosystem’s reliability and achieve a better performance compared with the previous scheme.
An Efficient Hardware-Based Fault-Tolerant Method for SMS4