Secure-Login

Secure Login Client–Server (TCP)

A minimal Python client–server authentication system demonstrating secure password handling using hashing and a local database.

The project shows how a TCP server can authenticate users against stored, hashed credentials.

Files

• Secure-Login/client.py – TCP client for login
• Secure-Login/server.py – multithreaded TCP authentication server
• Secure-Login/samples.py – initializes the user database with hashed passwords
• Secure-Login/userdata.db – SQLite database storing user credentials

Overview

• Client connects to a TCP server and submits username and password
• Server hashes the received password using SHA-256
• Credentials are verified against a SQLite database
• Server responds with login success or failure
• Supports multiple concurrent clients using threads

Security Features

• Passwords are never stored in plaintext
• SHA-256 hashing is used for password verification
• SQLite database used for credential storage

Running the Project

Requirements

• Python 3.9+

Initialize the database

Run once to create and populate the database:

python Secure-Login/samples.py

Start the server

python Secure-Login/server.py

Run the client (in a separate terminal)

python Secure-Login/client.py

Notes

• This project demonstrates authentication concepts only and is not production-ready.
• No encryption is applied to the TCP connection itself.
• Intended for educational use to illustrate hashing, sockets, and basic authentication logic.