Hyperion XDP: Kernel-Space Defense Engine

High-Performance Network Security Engine (eBPF/XDP)

Hyperion is a high-performance network security engine designed to enforce content-aware policy at the Network Interface Card (NIC) driver level. Unlike traditional firewalls that operate at the socket layer (Netfilter/iptables), Hyperion uses eBPF (Extended Berkeley Packet Filter) and XDP (Express Data Path) to reject malicious payloads before the Linux Kernel allocates memory (sk_buff).

Note

Project Status: Active Research (M5.0)

• Milestone: Telemetry + Flow Tracking (Complete).
• Engine: eBPF/XDP (Restricted C).
• Controller: Go (Cilium Library).
• Target: Cybersecurity Research Artifact.

Abstract & Research Context

This project serves as the Network Satellite to the Sentinel Runtime (Host Anchor). It explores the unification of process-level and packet-level defense.

The Research Question Can we inspect packet payloads for malicious signatures at wire speed (O(N)), dropping threats before the OS commits resources?

System Architecture

Hyperion operates on a split-plane design, utilizing the driver's interrupt context for maximum throughput.

The "Two Towers" Defense

Hyperion complements Sentinel by securing the transport boundary.

Dimension	Sentinel (The Host)	Hyperion (The Wire)
Boundary	Process Execution	Network Transport
Mechanism	ptrace / Kernel Modules	eBPF / XDP
Visibility	Syscalls (execve, open)	Payloads (GET /hack)
Constraint	Context-Aware Logic	Sub-microsecond Latency

Component Logic

• Kernel Enforcer (Restricted C): The "Muscle." Parses Layer 7 payloads directly in the driver. Implements verifier-safe bounded loops for Deep Packet Inspection (DPI).
• User Controller (Go/Cilium): The "Brain." Orchestrates BPF lifecycle. Handles SIGHUP for zero-downtime policy reloads via BPF Maps.
• Telemetry (Ring Buffer): The "Nerves." Streams structured binary events from Kernel to User Space for forensic logging.

Capability Milestones

We define success through distinct capability milestones.

Phase	Goal	Status	Outcome
M0	Foundation	[COMPLETE]	XDP_PASS skeleton compiling with Clang/LLVM.
M1	Stateless Filtering	[COMPLETE]	Validated XDP_DROP against hardcoded IP targets.
M2	Stateful Tracking	[COMPLETE]	Volumetric flood detection via BPF_MAP_TYPE_LRU_HASH.
M3	Static DPI	[COMPLETE]	Layer 7 Payload Analysis scanning for signatures.
M4	Dynamic Policy	[COMPLETE]	Hot-swappable rules via BPF_MAP_TYPE_ARRAY & SIGHUP.
M5	Telemetry	[COMPLETE]	Ring Buffer telemetry with 5-tuple flow tracking.

Research & Engineering Challenges

Important

Kernel Verifier Constraints The eBPF verifier enforces strict safety guarantees, creating unique engineering challenges:

• Bounded Loops: All loops must be provably terminating. Hyperion uses pragmatic bounds (512 iterations) for DPI scanning.
• Stack Limits: The BPF stack is constrained to 512 bytes. Complex parsing requires careful memory planning.
• Helper Restrictions: Only a subset of kernel helpers are available in XDP context (no socket access, no sleepable operations).

Performance vs. Expressiveness

• Deep Packet Inspection: String matching at wire speed requires creative algorithms. Hyperion implements a verifier-safe Boyer-Moore-like approach.
• Stateful Tracking: LRU hash maps balance memory efficiency with high-cardinality flows.
• Zero-Copy Telemetry: Ring buffers provide lock-free event streaming without per-packet memcpy overhead.

Integration Complexity

• Hot Reload: Updating BPF maps atomically while maintaining packet processing integrity.
• Multi-Interface Support: Managing lifecycle across diverse NIC drivers and modes (native vs. generic XDP).

Operational Manual

Prerequisites

• Linux Kernel 5.4+ (BTF Support)
• clang, llvm, make, golang

Quick Start (vM5)

1. Compile the Engine

make

2. Configure Signatures Define the payloads to block.

echo "root" > signatures.txt
echo "admin" >> signatures.txt

3. Attach to Interface Attach the XDP program to your network interface (e.g., eth0, wlp1s0).

sudo ./bin/hyperion_ctrl -iface wlp1s0

4. Enable Telemetry (Optional) Stream logs to a file for forensic analysis.

sudo ./bin/hyperion_ctrl -iface wlp1s0 -telemetry -logfile /var/log/hyperion.log

Tip

Dynamic Reload (Zero Downtime) You can modify signatures.txt while the engine is running. Trigger a hot-reload using SIGHUP to update the BPF Map instantly without dropping packets.

echo "malware" >> signatures.txt
sudo pkill -HUP hyperion_ctrl

Citation

@software{hyperion2026,
  author = {Nevin Shine},
  title = {Hyperion: High-Performance XDP Firewall},
  year = {2026},
  url = {https://github.com/nevinshine/hyperion-xdp}
}

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Nevin Shine (System Security Student) @ 2026