Book Image

Hands-On Network Programming with C

By : Lewis Van Winkle
Book Image

Hands-On Network Programming with C

By: Lewis Van Winkle

Overview of this book

Network programming enables processes to communicate with each other over a computer network, but it is a complex task that requires programming with multiple libraries and protocols. With its support for third-party libraries and structured documentation, C is an ideal language to write network programs. Complete with step-by-step explanations of essential concepts and practical examples, this C network programming book begins with the fundamentals of Internet Protocol, TCP, and UDP. You’ll explore client-server and peer-to-peer models for information sharing and connectivity with remote computers. The book will also cover HTTP and HTTPS for communicating between your browser and website, and delve into hostname resolution with DNS, which is crucial to the functioning of the modern web. As you advance, you’ll gain insights into asynchronous socket programming and streams, and explore debugging and error handling. Finally, you’ll study network monitoring and implement security best practices. By the end of this book, you’ll have experience of working with client-server applications and be able to implement new network programs in C. The code in this book is compatible with the older C99 version as well as the latest C18 and C++17 standards. You’ll work with robust, reliable, and secure code that is portable across operating systems, including Winsock sockets for Windows and POSIX sockets for Linux and macOS.
Table of Contents (26 chapters)
Title Page
About Packt

HTTPS server challenges

This chapter should serve only as an introduction to TLS/SSL server programming. There is much more to learn about secure network programming. Before deploying a secure HTTPS server with OpenSSL, it is essential to review all the OpenSSL documentation carefully. Many OpenSSL functions have edge cases that were ignored in the illustrative code for this chapter.

Multiplexing can also be complicated with OpenSSL. In typical TCP servers, we have been using the select() function to indicate when data is available to be read. The select() function works directly on the TCP socket. Using select() on a server secured with TLS/SSL can be tricky. This is because select() indicates when data is available at the TCP level. This usually, but not always, indicates that data is available to be read with SSL_read(). It is important that you carefully consult the OpenSSL documentation for SSL_read() if you are going to use it with select(). The example program in this chapter ignores...