# HTTP Input Service

A lightweight HTTP server that serves individual IPv4 addresses from cloud provider CIDR ranges.

## Purpose

Provides a continuous stream of IPv4 addresses to network scanning tools. Each consumer (identified by IP) receives addresses in randomized order from cloud provider IP ranges.

## Requirements

- Go 1.16+
- Cloud provider IP repository cloned at `./cloud-provider-ip-addresses/`

## Usage
```bash
# Build
go build -ldflags="-s -w" -o ip-feeder main.go

# Run
./ip-feeder
```

Server starts on `http://localhost:8080`

## API

**GET /**

Returns a single IPv4 address per request.
```bash
curl http://localhost:8080
# Output: 13.248.118.1
```

## Features

- **Per-consumer state** - Each client gets independent, deterministic sequence
- **Memory efficient** - Loads CIDR files lazily (~5-15MB RAM usage)
- **Lazy expansion** - IPs generated on-demand from CIDR notation
- **Randomized order** - Interleaves IPs from multiple ranges randomly
- **IPv4 only** - Filters IPv6, multicast, network/broadcast addresses
- **Graceful shutdown** - Ctrl+C drains connections cleanly

## Expected Input Format

Scans `./cloud-provider-ip-addresses/` for `.txt` files containing IP ranges:
```
# Comments ignored
13.248.118.0/24
52.94.0.0/16
3.5.140.0/22
```

## Shutdown

Press `Ctrl+C` for graceful shutdown with 10s timeout.