MOVRAX OS - Military-Grade Persistent Memory Operating System

Version: 1.0

1. Executive Summary

MOVRAX is a specialized, real-time operating system kernel designed for high-reliability and mission-critical applications. Unlike traditional general-purpose OSes, MOVRAX employs a persistent memory model, treating the filesystem as a direct memory-mapped structure rather than a separate I/O abstraction.

In Version 1.0, the OS has been hardened with military-grade features, including a deterministic preemptive scheduler, strict memory protection, and continuous system integrity verification.

2. Key Features

🛡️ Reliability & Security

• Watchdog Timer: A hardware-backed consistency check that halts the system if the kernel becomes unresponsive for more than 5 seconds.
• Audit Logging: An immutable, persistent ring buffer that records critical security events (Start-up, Login, Integrity Failures).
• Stack Protection: Canary values (GUARD_STACK_MAGIC) are placed at stack boundaries and checked periodically to detect overflows.
• W^X Memory Protection: Enforces strict separation between writable data and executable code to prevent code-injection attacks.

⚡ Real-Time Performance

• Preemptive Scheduler: A 256-level priority scheduler ensures critical tasks (e.g., crypto, sensors) always preempt lower-priority ones immediately.
• Deterministic Latency: The O(1) scheduler algorithm guarantees constant-time task selection regardless of system load.
• Priority Inheritance: mutexes automatically boost the priority of holding tasks to prevent priority inversion deadlocks.

💾 Persistent Memory Filesystem

• Zero-Copy I/O: Files are not "loaded"; they are mapped. Reading a file is just a memory pointer dereference.
• Integrity by Default: Every file and directory entry is protected by a CRC32 checksum verified on access.
• Encrypted Storage: All persistent data is obfuscated using a stream cipher to prevent casual offline inspection.

3. Technical Architecture

3.1 Kernel Layout

The kernel is a monolithic design compiled as a 32-bit ELF binary (kernel.bin).

Subsystem	Responsibility	Implementation File
PMM/VMM	Memory Allocation & Paging	pmm.cpp, paging.cpp
Scheduler	Task Scheduling & Context Switch	priority_scheduler.cpp
Interrupts	IDT, ISRs, IRQ Handling	idt.cpp, isr.asm
Integrity	CRC32 & Encryption	integrity.cpp
Audit	Security Event Logging	audit.cpp
Shell	Command Line Interface	shell.cpp

3.2 Memory Map

Address Range	Usage
0x00000000 - 0x00100000	Reserved (BIOS, IVT, Bootloader)
0x00100000 - 0x00400000	Kernel Code & Data (Identity Mapped)
0x00400000 - 0xC0000000	User Heap & Stacks
0xC0000000 - 0xC0100000	Persistent Filesystem (Simulated NVRAM)

4. Getting Started

4.1 Prerequisites

You need a Linux environment (or WSL on Windows) with the following tools:

• build-essential (Make, GCC)
• qemu-system-x86 (Emulator)
• xorriso (ISO creation)
• i686-elf-gcc / g++ (Cross-compiler)

4.2 Building

Run the make command in the project root:

make

This produces kernel.bin and a bootable mini-os.iso.

4.3 Running

To boot the OS in QEMU:

make run

4.4 Debugging

To attach GDB for kernel debugging:

make debug

Then connect with gdb -ex "target remote localhost:1234" kernel.bin.

5. Shell Commands

Once booted, the MOVRAX shell provides the following capabilities:

Command	Description
help	List available commands
status	NEW: Show live dashboard of all system subsystems
fscheck	NEW: Perform full filesystem integrity verification
audit	NEW: Dump the security event log
watchdog	NEW: Show watchdog timer statistics
ls / cd	Navigate the persistent filesystem
write	Create a file in persistent memory
cat	Read a file's content

6. License

This project is open-source software licensed under the MIT License.