HMAC with SHA Algorithm Implementation Source Code

In this article, we will discuss the implementation source code for HMAC using the SHA algorithm. HMAC is a highly valuable technique employed for data integrity verification and authentication. The HMAC implementation with SHA algorithm represents a method for computing hash-based message authentication codes. It accepts two primary inputs: a cryptographic key and the message payload, generating a MAC (Message Authentication Code) as output. Throughout our technical exploration, we will examine how to architect and implement this mechanism to ensure robust security and complete data protection. Our discussion will include practical code implementation approaches, such as: - Key padding techniques for block size alignment - Inner and outer hash computation workflows - SHA-256/SHA-512 algorithm integration patterns - Buffer management for large message processing Additionally, we will conduct an in-depth analysis of the SHA algorithm's operational principles, including its compression function mechanics and message scheduling process, to establish comprehensive understanding of HMAC's cryptographic foundations. The implementation will demonstrate proper error handling for invalid inputs and optimization techniques for high-performance environments. Let's begin our technical deep-dive!