Content filtering gateway realizing method based on network filter

Abstract

The method for implementing a content filtering gateway based on a network filter belongs to the technical field of network communication security, and is characterized in that network content analysis and real-time monitoring are realized based on a Linux system platform. The purpose of filtering application layer information at the network layer is achieved, and the network filter Netfilter framework is used to collect and filter data packets in the kernel state, optimize the network path of data packets, and improve the efficiency of data collection. Perform session restoration on the TCP connection, and use the shared memory technology between the user space and the kernel space to transfer the session content from the kernel state to the content filtering module in the user state. The overhead brought by the system call is avoided, and the number of data copies is reduced. Forward the legal data packets after judgment, and block them illegally. The gateway works in a transparent manner, and the gateway does the necessary processing without losing transparency due to caching data. The gateway can effectively complete network content analysis and real-time monitoring.

Description

technical field [0001] The invention belongs to the technical field of communication, and specifically designs collection and filtering of data packets in a kernel state, session restoration, communication between a user state and a kernel state, realization of a transparent mode, and the like. Filtering can be performed based on the complete content of the session to prevent illegal data packets from passing. Background technique [0002] The Internet satisfies the supreme realm of "fast" and "unrestricted" that people have been pursuing for thousands of years, breaks through time and space, and realizes people's dream of freedom. It fits the original nature of people, and the degree of "freedom" achieved exceeds people's imagination. The openness of the Internet has allowed people to enjoy the freedom of unfettered access to various information, release of speech, but at the same time, it has also brought many information security problems. [0003] Statistics show that ...

AI Technical Summary

Problems solved by technology

There are various kinds of information on the Internet, most of which have not been strictly checked and screened. Although they can meet the needs of some education, information and leisure, there are also a large number of obscene, pornographic, Violent terror, anti-government and racial discrimination websites

[0004] The second category of security concerns is the threat of virus infection and spam

The application layer agent can understand various application protocols and can conveniently filter content, but it is opaque to users, and different agent programs must be written for each application

And slower speed, greater impact on network performance

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