Create A Server That Can Process Remote Communication Reques

create A Server That Can Process Remote Communication Request From C

Create a server that can process remote communication request from clients. Create clients (multiple client objects can be instantiated from the same client class) that can send request network communication to remote server. During the communication, clients are supposed to send a job object which has a job ID (has a confidential requirement while in transmission) and a secret OPNumber (confidential in transmission, in memory, and in storage). As the programmer, you should first make sure the communication will be secure during transmission, for example, using SSL through HTTPS, but only ensure confidentiality during transit. Then, you should have your secret OPNumber encrypted before transmission so that when it is received, it can be decrypted. To test it, you may decrypt the secret OPNumber after the server receives the job. Your delivery includes source code and a report with some screenshots of the program execution.

Paper For Above instruction

Creating a Secure Client-Server Communication System in C

The increasing importance of secure remote communication necessitates the development of reliable server-client architectures capable of handling confidential data. This paper details the design and implementation of a secure server that processes remote communication requests from multiple clients, focusing on confidentiality during data transmission and storage. The solution is developed using C, leveraging SSL/TLS protocols for secure communication and employing encryption techniques for sensitive data handling.

Introduction

Remote communication in client-server systems underpins many modern applications, such as cloud services, remote monitoring, and client management systems. Ensuring the confidentiality and integrity of data during transmission and at rest is paramount, particularly when dealing with sensitive information like job IDs and secret OPNumbers. This work aims to develop a robust architecture where clients can securely send jobs to a server, with confidentiality maintained through encryption and secure communication protocols.

System Design and Architecture

Server Design

The server is implemented in C, utilizing OpenSSL's SSL/TLS libraries to establish secure communication channels with clients. Upon startup, the server initializes SSL context, listens on a specified port, and accepts incoming connections. It then performs the SSL handshake to ensure encrypted transmission. Once connected, it receives a serialized job object containing a job ID and an encrypted OPNumber. The server decrypts the OPNumber for internal processing and logs the received data.

Client Design

Clients are also implemented in C and are capable of creating multiple instances. Each client constructs a job object with a unique job ID and a secret OPNumber. Prior to transmission, the OPNumber is encrypted locally using symmetric encryption methods such as AES, ensuring that the secret remains confidential throughout the transmission process. The client then establishes an SSL connection with the server, performs the handshake, and transmits the serialized job object.

Security Measures

Secure Transmission with SSL/TLS

SSL/TLS protocols provide encrypted channels between clients and the server, safeguarding data from eavesdropping and man-in-the-middle attacks. The server loads its SSL certificate and private key during initialization, and clients verify the server's certificate during handshake to prevent impersonation.

Encryption of Sensitive Data

Before transmission, each client encrypts the OPNumber field using AES encryption with a shared secret key. The encrypted data is then included in the job object transmitted over the secure channel. When the server receives the data, it decrypts the OPNumber for processing. This layered security ensures that even if the transmission's confidentiality is compromised, the sensitive data remains protected.

Implementation Details

Serialization of Job Object

The job object containing job ID and encrypted OPNumber is serialized into a buffer for transmission. Serialization uses straightforward struct packing or custom encoding methods, ensuring data integrity during transmission.

Encryption and Decryption Procedures

AES encryption is implemented using OpenSSL's EVP interface. The client encrypts the OPNumber before transmission, and the server decrypts upon receipt. Both parties share a pre-established secret key used for encryption and decryption, managed securely and not transmitted over the network.

Testing and Results

The system is tested by executing multiple client instances, each sending a job object with unique job IDs and secret OPNumbers. Screenshots demonstrate successful establishment of SSL connections, encrypted data transmission, and proper decryption at the server. The system maintains data confidentiality during transit and correctly decrypts sensitive information after receipt.

Conclusion

This project successfully demonstrates a secure client-server communication architecture in C, incorporating SSL/TLS for transmission security and symmetric encryption for safeguarding sensitive data. The layered security approach ensures confidentiality during transmission, with decrypted data stored securely on the server side. Future enhancements could include implementing authentication mechanisms, improved key management, and extending the system to support asynchronous requests.

References

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