osdev-networking

What problem does it solve?

Building a full network stack for an operating system from the NIC driver up is complex, error-prone, and requires coordinating hardware access, protocol parsing, and transport state machines; this Skill codifies the reference patterns and implementation notes needed to complete that work reliably.

Core Features & Use Cases

• NIC driver guidance: Practical init sequences, register maps, MMIO/PIO access patterns, DMA buffer requirements, and descriptor ring management for RTL8139, e1000, and virtio-net.
• Protocol implementations: End-to-end guidance for Ethernet framing, ARP resolution and caching, IPv4 header handling and checksum, UDP/TCP transport behavior, pseudo-header checksums, and DHCP basics.
• Debugging and integration: Packet receive/transmit flows, IRQ handling tips, common pitfalls, and ordering for incremental development from NIC → Ethernet → ARP → IPv4 → UDP/ICMP → TCP.
• Use Case Example: Implement a QEMU-tested e1000 driver, verify receive/transmit via ARP and ICMP ping, then add UDP-based DHCP for IP configuration.

Quick Start

Build a minimal TCP/IP stack by first implementing the NIC driver and DMA-safe buffers, then Ethernet framing, ARP resolution, IPv4 header handling and checksum, UDP and DHCP, and finally TCP with its state machine.