Mail Encryption using ChaCha20

—Email communication plays a vital role in modern society, facilitating both personal and professional interactions. However, ensuring the security and confidentiality of sensitive information exchanged via email remains a significant concern. This project presents the development and implementation of an email filter utilizing the ChaCha20 encryption algorithm. ChaCha20 is a symmetric stream cipher algorithm designed by Daniel J. Bernstein. It's often used in encryption protocols and applications, particularly in the context of securing internet traffic. It's known for its speed and security, and it's part of the TLS (Transport Layer Security) protocol suite, among other applications. ChaCha20 operates on 64-byte blocks and uses a key size of 256 bits. It's considered to be quite secure and has seen widespread adoption in various security-sensitive applications. Before encryption can occur, a cryptographic key needs to be generated. For ChaCha20, a secure random key is typically generated. The key should be kept secret and shared only between the sender and the intended recipient(s). For maximum security, ChaCha20 encryption in email is often implemented as part of an end-to-end encryption scheme. This means that the content of the email is encrypted on the sender's device and can only be decrypted by the intended recipient, with no intermediary (including email service providers) having access to the plaintext. Overall, ChaCha20 plays a crucial role in ensuring the confidentiality of email communication by encrypting the content of messages, thereby protecting it from unauthorized access or interception.