Does linux have a libpcap library?

There is the libpcap library in Linux; the libpcap library is a network packet capture function library that provides an API for capturing packets directly from the data link layer of a Unix-derived operating system. The libpcap library is popular Used by packet capture applications, enabling them to run on almost any flavor of Unix.

#The operating environment of this tutorial: linux7.3 system, Dell G3 computer.

linux has libpcap library

Overview

libpcap is a network packet capture function library with very powerful functions. The famous tcpdump under Linux is based on It's based on.

Libpcap is an open source C library that provides an API for capturing packets directly from the data link layer of Unix-derived operating systems. It is used by popular packet capture applications such as tcpdump and snort, allowing them to run on almost any flavor of Unix.

The main functions of libpcap

1) Capture various data packets, such as: network traffic statistics.

2) Filter network data packets, for example: filter out some local data, similar to a firewall.

3) Analyze network data packets, such as: analyzing network protocols and collecting data.

4) Store network packets, e.g. save captured data for future analysis.

Installation of libpcap

Basic steps for developing applications using the libpcap function library:

1. Open Network device

2. Set filtering rules

3. Capture data

4. Close network device

libpcap packet capture framework

• pcap_lookupdev(): The function is used to find network devices and returns a pointer to the network device name that can be called by the pcap_open_live() function.

• pcap_lookupnet(): The function obtains the network number and mask of the specified network device.

• pcap_open_live(): The function is used to open the network device and return the packet capture descriptor used to capture network packets. All operations on this network device are based on this network device descriptor.

• pcap_compile(): The function is used to compile the filtering strategy specified by the user into the filtering program.

• pcap_setfilter(): Function is used to set the filter.

• pcap_loop(): The function pcap_dispatch() function is used to capture data packets. It can also be processed after capture. In addition, pcap_next() and pcap_next_ex() two Functions can also be used to capture packets.

• pcap_close(): Function is used to close network devices and release resources.

Recommended learning: Linux video tutorial

The above is the detailed content of Does linux have a libpcap library?. For more information, please follow other related articles on the PHP Chinese website!