vCrypto

Virtual Cryptographic Hardware Coprocessor (Linux Kernel Module)

Status: Work in Progress (Active Development)

vCrypto is a Linux Kernel driver (Ring 0) designed to simulate a physical cryptographic hardware coprocessor. Instead of allocating isolated buffers per user session, this module implements a Global Hardware State architecture, acting as a single shared resource across the operating system.

Architecture & Core Concepts

This project is built to demonstrate robust kernel-space engineering, focusing on thread safety, memory management, and process isolation.

• Singleton Hardware Simulation: The device state is allocated once at module initialization (__init) using kmalloc. It simulates a single physical chip soldered to the motherboard.
• Concurrency & Thread Safety: Because the hardware buffer is a shared global resource, vCrypto implements strict Mutex locking (mutex_lock / mutex_unlock). This prevents Race Conditions and memory corruption when multiple user-space threads (Ring 3) attempt to read/write concurrently.
• Exclusive Access (Access Control): The open and release file operations act as a hardware gatekeeper. If Process A opens the device, it returns -EBUSY to any other process attempting to connect, enforcing strict exclusive access.
• Miscdevice Interface: Utilizes the Linux miscdevice API for clean dynamic minor number allocation and boilerplate reduction, while manually handling the lifecycle in the initialization phase.
• Pointer Arithmetic: Implements the container_of macro to safely retrieve the primary data structure from the generic file->private_data pointer during I/O operations.

Current Development Phase

The module is currently compilable and can be loaded into the kernel via insmod.

• Global memory allocation and device registration.
• Mutex initialization and Race Condition protection.
• File operations boilerplate (open, release, read, write).
• IOCTL interface skeleton (VCRYPTO_SET_KEY, VCRYPTO_RESET).
• User-space CLI tool implementation for testing.
• Advanced encryption algorithms integration.

Building and Loading

(Instructions will be updated as the Makefile structure is finalized).

make
sudo insmod vcrypto.ko
dmesg | tail

Developed by Marcos Andrade for architectural study of the Linux Kernel.