Key-leakage hardware Trojan with super concealment based on the fault injection for block cipher of SM4

In the security system, there is a lot of sensitive information, and the leakage of the secret key will cause security failure. In this Letter, combining the fault injection analysis of SM4 (Chinese block cipher algorithm standard), a key leakage Trojan payload circuit that requires only 4 XOR gates was designed and verified. By estimation, the area and power consumption is <1% of that in popular solutions. The scheme was successfully verified using FPGA. This Letter makes contribution to the defence for key-leakage type Trojan.