VIDEOS 》 Online Course - Linux CLI Scripting

libpcap is a very popular user-space networking library, with which you can capture and or generate packets. libpcap is the underlying framework for many popular packet capture tools such as tcpdump, Wireshark and so on. In fact libpcap is a part of tcpdump project. But besides just using it as a packet capture tool, you can use libpcap in various applications, such as user-space based networking stack development, etc. In some cases libpcap is yet another alternative to raw-sockets and tun/tap interfaces.

Here is my multi-episode video series where I demonstrate how you can port the my libpcap sample code, discussed in the earlier episode to raw-socket. This code should further help you to design and architect your own user-space Network stack on top of this fundamental framework.

GNU Zebra is one of the oldest open-source Dynamic Routing Protocol suite stack developed by Kunihiro Ishiguro. Zebra supports features such as RIPv1/RIPv2 for IPv4 and RIPng for IPv6, OSPFv2 and OSPFv3, BGPv4+ and so on. Zebra is an active project for many years. After many years of active support Zebra is discontinued, and sometime down the lane a new fork is created from Zebra called Quagga which is now maintained by a separate independent open-source community. Quagga is a routing software suite, providing implementations of OSPFv2, OSPFv3, RIP v1 and v2, RIPng and BGP-4 for Unix platforms, particularly FreeBSD, Linux, Solaris and NetBSD. Quagga is a fork of GNU Zebra which was developed by Kunihiro Ishiguro. The Quagga architecture consists of a core daemon, zebra, which acts as an abstraction layer to the underlying Unix kernel and presents the Zserv API over a Unix or TCP stream to Quagga clients.

Inline programming is a technique where code statements are included directly in the text of a program, instead of being contained in separate files or modules. Inline programming can be useful for small or simple tasks, as it can eliminate the need for a separate script or function. One common example of inline programming is using JavaScripts, Php, etc in HTML documents to create dynamic content. Similarly in Linux Kernel we can find lot of instances where we can find inline programming such as inline assembly and now Rust within the Kernel source.