A USBKEY Calling Method Based on IPSEC XFRM Framework

This paper proposes a method of hardware encryption and decryption by calling the hardware USB KEY under the XFRM framework of IPSEC. The XFRM framework configures the algorithm used by the protocol in the security association SA to call the kernel CRYPTO algorithm framework. The algorithm framework calls the hardware algorithm in the code, but only implements the algorithm module of the PCIE and APB bus, and does not implement the method call of USB. During ESP processing, the CRYPTO framework is in the process of network interrupt processing. Calling USB devices directly will generate new interrupts, leading to interrupt conflicts. If it is a single core embedded CPU, it will directly lead to kernel crash. Through the use of asynchronous algorithm registration, kernel thread call, URB framework adjustment, SG device node modification and other means, network interrupts can be released in a timely manner to solve the problem of soft interrupt conflicts, and the successful call to USB devices in the single core embedded CPU scenario can be achieved; Both kernel mode and user mode program calls are satisfied, and the functions are not affected by each other.