meraki-fluxgen 1.0.0

Multi-client traffic generator inspired by hping3

fluxgen

fluxgen is a powerful multi-client traffic generator inspired by hping3. It simulates many clients on a single Linux host, sending customizable network traffic with spoofed IP/MAC addresses from the same subnet. Perfect for network testing, load testing, and security research.

Companion Tool: Check out FluxProbe - a schema-driven protocol fuzzer for security testing and vulnerability discovery.

Features

• Multi-client simulation - Simulate hundreds of clients from a single host
• Protocol support - TCP, UDP, ICMP, IGMP, GRE, ESP, AH, SCTP
• Spoofed identities - Unique IP/MAC addresses per simulated client
• Flexible traffic patterns - Randomize sources, destinations, ports
• Custom payloads - Send text or hex-encoded data
• Traffic capture - Export sent traffic to PCAP files
• Load testing - Flood mode for maximum throughput
• Configuration files - YAML/JSON configuration support

Installation

Prerequisites

• Python 3.8+ (tested with Python 3.12)
• Linux operating system (required for raw socket support)
• Root privileges or CAP_NET_RAW capability
• Git for cloning the repository
• pip for universal fallback installation

Quick Install (Recommended)

Works on all Linux flavors listed below and avoids distro package conflicts:

python3 -m venv ~/.venvs/fluxgen
~/.venvs/fluxgen/bin/pip install --upgrade pip
~/.venvs/fluxgen/bin/pip install git+https://github.com/kanchankjha/fluxgen.git
~/.venvs/fluxgen/bin/fluxgen --help

Run traffic commands with root/capabilities:

sudo ~/.venvs/fluxgen/bin/fluxgen --help

Distro Package Install (Optional)

Current packaging and CI target:

• Debian family: Debian, Ubuntu, Kali, Parrot (APT)
• RHEL family: CentOS Stream / compatible (RPM)

Use distro packages if you prefer system-managed installs.

Debian/Ubuntu/Kali/Parrot (APT)

curl -fL https://raw.githubusercontent.com/kanchankjha/fluxgen/apt-repo/fluxgen.gpg.key -o /tmp/fluxgen.gpg.key
sudo gpg --dearmor --yes -o /usr/share/keyrings/fluxgen-archive-keyring.gpg /tmp/fluxgen.gpg.key
echo "deb [arch=all signed-by=/usr/share/keyrings/fluxgen-archive-keyring.gpg] https://raw.githubusercontent.com/kanchankjha/fluxgen/apt-repo stable main" | sudo tee /etc/apt/sources.list.d/fluxgen.list
sudo apt-get update
sudo apt-get install -y fluxgen

CentOS Stream / RHEL-like (RPM)

# 1) Add repository
sudo tee /etc/yum.repos.d/fluxgen.repo >/dev/null <<'EOF'
[fluxgen]
name=Fluxgen RPM Repository
baseurl=https://raw.githubusercontent.com/kanchankjha/fluxgen/yum-repo/
enabled=1
gpgcheck=0
repo_gpgcheck=0
EOF

# 2) Install package
sudo dnf makecache
sudo dnf install -y fluxgen

Universal Linux Fallback (pip)

This is the same as the Quick Install above.

If/when published to PyPI, you can use:

~/.venvs/fluxgen/bin/pip install meraki-fluxgen

fluxgen on PyPI is already used by another project, so this project publishes the Python package under meraki-fluxgen while keeping the CLI command name as fluxgen.

Source Install (Development)

git clone https://github.com/kanchankjha/fluxgen.git
cd fluxgen
python3 -m venv .venv
source .venv/bin/activate
pip install --upgrade pip
pip install -e ".[dev]"
fluxgen --help

Note: fluxgen requires Linux for raw socket support. macOS and Windows are not supported for packet sending.

Grant Network Capabilities

fluxgen needs raw socket access to craft and send custom packets. You have two options:

Option A: Run with sudo (Simple but less secure)

sudo fluxgen --interface eth0 --clients 5 --dst 10.0.0.5 --dport 80

Option B: Grant Capabilities (Recommended)

# Grant capabilities to Python interpreter
sudo setcap cap_net_raw,cap_net_admin+ep .venv/bin/python3

# Or if installed system-wide
sudo setcap cap_net_raw,cap_net_admin+ep $(which python3)

# Now you can run without sudo
fluxgen --interface eth0 --clients 5 --dst 10.0.0.5 --dport 80

Verify capabilities:

getcap .venv/bin/python3
# Should show: cap_net_admin,cap_net_raw=ep

Verify Installation

# Check version and help
fluxgen --help

# Test with dry-run (no packets sent)
fluxgen --interface eth0 --clients 2 --dst 192.168.1.1 --dport 80 --count 5 --dry-run

# Send a few test packets (requires root/capabilities)
fluxgen --interface eth0 --clients 2 --dst 192.168.1.1 --dport 80 --count 5

For Developers

If you plan to modify or contribute to fluxgen:

# Clone the repository
git clone https://github.com/kanchankjha/fluxgen.git
cd fluxgen

# Install with development dependencies
pip install -e ".[dev]"

# This installs:
# - pytest>=7.0 - Testing framework
# - pytest-cov>=4.0 - Coverage reporting
# - pytest-mock>=3.10 - Mocking support

# Run tests to verify setup
pytest tests/ -v

# Run with coverage report
pytest tests/ --cov=fluxgen --cov-report=html
open htmlcov/index.html

Quick Start Guide

1. Basic TCP SYN Flood

Simulate 10 clients sending TCP SYN packets:

fluxgen --interface eth0 --clients 10 --dst 10.0.0.5 --dport 80 --proto tcp --flags S --count 100 --interval 0.01

2. UDP Traffic Generation

Send UDP packets from multiple sources:

fluxgen --interface eth0 --clients 20 --dst 192.168.1.100 --dport 53 --proto udp --count 500 --interval 0.005

3. ICMP Ping Flood

Simulate multiple clients pinging a target:

fluxgen --interface eth0 --clients 50 --dst 8.8.8.8 --proto icmp --icmp-type 8 --icmp-code 0 --count 1000 --flood

4. Random Source and Destination

Test with randomized traffic patterns:

fluxgen --interface eth0 --clients 15 --dest-subnet 10.0.0.0/24 --rand-dest --rand-source --proto tcp --dport 80 --count 200

5. Custom Payload

Send packets with custom data:

# Text payload
fluxgen --interface eth0 --clients 5 --dst 10.0.0.5 --dport 8080 --proto tcp --payload "Hello Server" --count 10

# Hex payload
fluxgen --interface eth0 --clients 5 --dst 10.0.0.5 --dport 8080 --proto udp --payload "deadbeef" --payload-hex --count 10

# Auto-generated payload of specific size
fluxgen --interface eth0 --clients 2 --dst 10.0.0.5 --dport 53 --proto udp --data-size 512 --count 5

# IPv6 example (auto-detects family)
fluxgen --interface eth0 --clients 3 --dst 2001:db8::50 --dport 443 --proto tcp --ip-version auto --count 20

6. PCAP Capture

Export sent traffic for analysis:

fluxgen --interface eth0 --clients 10 --dst 10.0.0.5 --dport 443 --proto tcp --flags S --count 100 --pcap-out traffic.pcap

7. Configuration File

Use YAML configuration for complex scenarios:

# config.yaml
interface: eth0
clients: 100
dst: 192.168.1.50
dport: 80
proto: tcp
flags: S
count: 1000
interval: 0.001
rand_source: true
pcap_out: load_test.pcap

fluxgen --config config.yaml

Usage

fluxgen --interface eth0 --clients 10 --dst 10.0.0.5 --dport 80 --proto tcp --flags S --count 100 --interval 0.01

Key flags:

• --subnet-pool CIDR to allocate client IPs (defaults to interface subnet)
• --rand-source randomize client identity per packet
• --rand-dest --dest-subnet 10.0.0.0/24 randomize destination IPs
• --payload "deadbeef" --payload-hex send custom payload, or --data-size 1024 to auto-fill a payload
• --frag --frag-size 500 --frag-mode random enable fragmentation with fixed or randomized fragment sizes
• --ip-version 4|6|auto force IPv4/IPv6 or let fluxgen infer from destinations
• --flood remove delay, --dry-run craft packets only, --pcap-out out.pcap write sent frames

Common Use Cases

Load Testing a Web Server

# Simulate 100 concurrent clients
fluxgen --interface eth0 --clients 100 --dst webserver.local --dport 80 \
    --proto tcp --flags S --count 10000 --interval 0.001 \
    --pcap-out webserver_load.pcap

DDoS Simulation (Controlled Environment)

# High-rate flood from many sources
fluxgen --interface eth0 --clients 500 --dest-subnet 10.0.0.0/24 \
    --rand-dest --rand-source --proto tcp --dport 80 --flags S \
    --flood --count 50000

Network Device Stress Testing

# Test router/firewall with diverse traffic
fluxgen --interface eth0 --clients 50 --dst 192.168.1.1 \
    --proto tcp --dport 443 --flags SA --ttl 32 \
    --count 5000 --interval 0.002 --verbose

Protocol Testing

# Test ICMP handling
fluxgen --interface eth0 --clients 20 --dst target.local \
    --proto icmp --icmp-type 8 --icmp-code 0 \
    --count 1000 --interval 0.01

# Test UDP services
fluxgen --interface eth0 --clients 30 --dst dns-server.local \
    --proto udp --dport 53 --sport 50000 \
    --payload "test" --count 500

Multicast Testing (IGMP)

# Send IGMP membership reports
fluxgen --interface eth0 --clients 10 --dst 224.0.0.1 \
    --proto igmp --count 100 --interval 0.1

VPN/Tunnel Testing (GRE, ESP)

# Test GRE tunneling
fluxgen --interface eth0 --clients 5 --dst tunnel-endpoint.local \
    --proto gre --payload "encapsulated" --count 200

# Test IPsec ESP
fluxgen --interface eth0 --clients 5 --dst vpn-gateway.local \
    --proto esp --count 100

Advanced Examples

Fragmented Traffic

# Send fragmented IP packets
fluxgen --interface eth0 --clients 10 --dst 10.0.0.5 --dport 80 \
    --proto tcp --frag --frag-size 512 --count 100

Custom IP Options

# Set custom TTL, TOS, and IP ID
fluxgen --interface eth0 --clients 5 --dst 10.0.0.5 --dport 22 \
    --proto tcp --ttl 16 --tos 0x10 --ip-id 12345 --count 50

Dry Run for Testing

# Build packets without sending (test configuration)
fluxgen --interface eth0 --clients 100 --dst 10.0.0.5 --dport 80 \
    --proto tcp --flags S --count 10 --dry-run --verbose

CLI Reference

Complete Parameter Reference

Configuration

• --config PATH - Load settings from YAML/JSON configuration file

Required Parameters

• --interface IFACE - Network interface to send packets on (e.g., eth0, wlan0)
• --dst IP - Destination IP address (required unless using --dest-subnet)

Client Simulation

• --clients N - Number of simulated clients with unique IPs/MACs (default: 1)
• --subnet-pool CIDR - IP range for client addresses (default: interface subnet)
• --rand-source - Randomize source identity for each packet

Destination Options

• --dest-subnet CIDR - IP range for random destination addresses
• --rand-dest - Randomize destination IP per packet (uses --dest-subnet if provided)

Protocol Settings

• --proto {tcp,udp,icmp,igmp,gre,esp,ah,sctp} - Transport/network protocol (default: tcp)

TCP/UDP/SCTP Options

• --dport N - Destination port (1-65535)
• --sport N - Source port (1-65535, default: random)
• --flags STRING - TCP flags: S (SYN), A (ACK), F (FIN), R (RST), P (PSH), U (URG) (default: S)

ICMP Options

• --icmp-type N - ICMP type (default: 8 for echo request)
• --icmp-code N - ICMP code (default: 0)

IP Layer Options

• --ttl N - IP Time-To-Live (default: 64)
• --tos N - IP Type of Service / DSCP value (default: 0)
• --ip-id N - IP identification field (default: random)
• --frag - Enable IP fragmentation
• --frag-size N - Fragment size in bytes (requires --frag)

Payload Options

• --payload STRING - Packet payload as text
• --payload-hex - Interpret payload as hexadecimal string (e.g., "deadbeef")

Traffic Control

• --count N - Packets to send per client (0 = infinite, default: 0)
• --interval SECONDS - Delay between packets (default: 0.1 seconds)
• --flood - Remove delay between packets (maximum speed)

Output and Debugging

• --pcap-out PATH - Write sent packets to PCAP file
• --dry-run - Build packets without sending (test configuration)
• --verbose - Print detailed error messages for send/craft failures
• --quiet - Suppress periodic statistics output

Examples by Scenario

Web Server Load Testing

# Simulate 200 users making HTTP requests
fluxgen --interface eth0 --clients 200 --dst web.example.com --dport 80 \
    --proto tcp --flags S --count 5000 --interval 0.002

DNS Server Testing

# Simulate 50 clients making DNS queries
fluxgen --interface eth0 --clients 50 --dst 8.8.8.8 --dport 53 \
    --proto udp --payload "example.com" --count 1000 --interval 0.01

Firewall Rule Testing

# Test firewall with various ports and protocols
fluxgen --interface eth0 --clients 10 --dst firewall.local \
    --proto tcp --dport 443 --flags S --ttl 64 --count 500 \
    --pcap-out firewall_test.pcap

Network Monitoring Tool Testing

# Generate diverse traffic patterns for IDS/IPS testing
fluxgen --interface eth0 --clients 100 --dest-subnet 192.168.1.0/24 \
    --rand-dest --rand-source --proto tcp --dport 80 --flags S \
    --count 10000 --interval 0.001 --verbose

Supported Protocols

fluxgen supports a wide range of network protocols for comprehensive testing:

Layer 4 Protocols

TCP (Transmission Control Protocol)

• Full control over TCP flags (SYN, ACK, FIN, RST, PSH, URG)
• Custom source and destination ports
• Ideal for connection-oriented testing

fluxgen --interface eth0 --dst target --dport 80 --proto tcp --flags S

UDP (User Datagram Protocol)

• Connectionless packet delivery
• Custom payloads and ports
• Perfect for DNS, DHCP, streaming protocols

fluxgen --interface eth0 --dst target --dport 53 --proto udp

SCTP (Stream Control Transmission Protocol)

• Multi-homing support
• Message-oriented reliability
• Used in telecom and signaling

fluxgen --interface eth0 --dst target --dport 5060 --proto sctp

Layer 3 Protocols

ICMP (Internet Control Message Protocol)

• Echo requests (ping)
• Customizable type and code
• Network diagnostics and reachability testing

fluxgen --interface eth0 --dst target --proto icmp --icmp-type 8 --icmp-code 0

IGMP (Internet Group Management Protocol)

• Multicast group management
• Test multicast routing and switches
• Membership reports and queries

fluxgen --interface eth0 --dst 224.0.0.1 --proto igmp

GRE (Generic Routing Encapsulation)

• IP tunneling protocol
• Test VPN and tunnel endpoints
• Encapsulation of various protocols

fluxgen --interface eth0 --dst tunnel-endpoint --proto gre

IPsec Protocols

ESP (Encapsulating Security Payload)

• IPsec encryption protocol
• Test VPN gateways
• Encrypted packet delivery

fluxgen --interface eth0 --dst vpn-gateway --proto esp

AH (Authentication Header)

• IPsec authentication protocol
• Integrity verification
• Test IPsec implementations

fluxgen --interface eth0 --dst vpn-gateway --proto ah

Troubleshooting

Common Issues and Solutions

1. "Permission denied" or "Operation not permitted"

Problem: fluxgen requires raw socket access to craft custom packets.

Solutions:

# Solution A: Run with sudo
sudo fluxgen --interface eth0 --dst 10.0.0.5 --dport 80

# Solution B: Grant capabilities (recommended)
sudo setcap cap_net_raw,cap_net_admin+ep $(which python3)
# Or for venv:
sudo setcap cap_net_raw,cap_net_admin+ep .venv/bin/python3

# Verify capabilities
getcap $(which python3)

2. "No such device" or interface not found

Problem: Invalid or non-existent network interface.

Solutions:

# List available interfaces
ip link show
# Or
ifconfig -a

# Use correct interface name
fluxgen --interface enp0s3 --dst 10.0.0.5 --dport 80

3. "ModuleNotFoundError: No module named 'scapy'"

Problem: Dependencies not installed.

Solution:

# Install all dependencies
pip install -r requirements.txt

# Or install individually
pip install scapy psutil pyyaml netifaces

4. No packets being sent (dry-run mode)

Problem: Accidentally running in dry-run mode.

Solution:

# Remove --dry-run flag
fluxgen --interface eth0 --dst 10.0.0.5 --dport 80 --count 10
# Not: ... --dry-run

5. "Cannot allocate memory" or system slowdown

Problem: Too many clients or flood mode overwhelming system.

Solutions:

# Reduce number of clients
fluxgen --interface eth0 --clients 50 --dst target --dport 80
# Instead of: --clients 10000

# Add interval (remove --flood)
fluxgen --interface eth0 --clients 100 --dst target --dport 80 --interval 0.001

# Monitor system resources
htop  # or top

6. Packets not reaching destination

Problem: Firewall, routing, or network configuration issues.

Troubleshooting:

# Check if target is reachable
ping target-ip

# Verify routing
ip route show
traceroute target-ip

# Check firewall rules
sudo iptables -L -n -v

# Test with PCAP capture
fluxgen --interface eth0 --dst target --dport 80 --count 10 --pcap-out test.pcap
# Verify with Wireshark: wireshark test.pcap

# Enable verbose mode
fluxgen --interface eth0 --dst target --dport 80 --count 10 --verbose

7. Python version incompatibility

Problem: fluxgen requires Python 3.8+.

Solution:

# Check Python version
python3 --version

# Upgrade if needed (Ubuntu/Debian)
sudo apt update
sudo apt install python3.11

# Or use pyenv for version management
pyenv install 3.11.0
pyenv local 3.11.0

Getting Help

# Display all available options
fluxgen --help

# Test with minimal configuration
fluxgen --interface eth0 --dst 127.0.0.1 --dport 8080 --count 5 --dry-run

# Run with verbose output for debugging
fluxgen --interface eth0 --dst target --dport 80 --count 10 --verbose

# Check packet crafting without sending
fluxgen --interface eth0 --clients 5 --dst target --dport 80 --count 2 --dry-run --verbose

Debug Workflow

# Step 1: Verify installation
fluxgen --help

# Step 2: Test packet building (no sending)
fluxgen --interface eth0 --dst 192.168.1.1 --dport 80 --count 1 --dry-run --verbose

# Step 3: Send to localhost first
fluxgen --interface lo --dst 127.0.0.1 --dport 8080 --count 5

# Step 4: Capture and inspect packets
fluxgen --interface eth0 --dst target --dport 80 --count 10 --pcap-out debug.pcap
wireshark debug.pcap

# Step 5: Gradually increase complexity
fluxgen --interface eth0 --clients 2 --dst target --dport 80 --count 10
fluxgen --interface eth0 --clients 10 --dst target --dport 80 --count 100

Project Structure

fluxgen/
├── fluxgen/               # Main package directory
│   ├── __init__.py      # Package initialization
│   ├── __main__.py      # Entry point for `python -m fluxgen`
│   ├── cli.py           # Command-line interface and argument parsing
│   ├── config.py        # Configuration file loading (YAML/JSON)
│   ├── identity.py      # Client identity generation (IP/MAC)
│   ├── netinfo.py       # Network interface introspection
│   ├── packet_builder.py # Packet crafting with Scapy
│   └── sender.py        # Multi-client orchestration and sending
├── tests/               # Unit tests
│   ├── test_cli.py      # CLI argument parsing tests
│   ├── test_config.py   # Configuration file tests
│   ├── test_identity.py # Client identity tests
│   ├── test_netinfo.py  # Network interface tests
│   ├── test_packet_builder.py # Packet building tests
│   └── test_sender.py   # Sender orchestration tests
├── pyproject.toml       # Project metadata and dependencies
├── requirements.txt     # Runtime dependencies
└── README.md           # This file

Key Modules

• cli.py: Parses command-line arguments, validates inputs, and orchestrates execution
• identity.py: Generates unique client identities (source IPs, MACs) within subnet constraints
• netinfo.py: Queries system network interfaces using psutil and netifaces
• packet_builder.py: Constructs protocol packets using Scapy with custom fields
• sender.py: Manages multiple client threads/processes, sends packets, and collects statistics
• config.py: Loads configuration from YAML/JSON files for reproducible testing scenarios

Testing

fluxgen includes comprehensive unit tests for all modules.

Running Tests

# Install development dependencies
pip install pytest pytest-cov pytest-mock

# Run all tests
pytest

# Run with coverage report
pytest --cov=fluxgen --cov-report=html

# Run specific test file
pytest tests/test_packet_builder.py

# Run tests with verbose output
pytest -v

# Run tests matching a pattern
pytest -k "test_tcp"

Test Coverage

The test suite covers:

• ✅ CLI argument parsing and validation
• ✅ Configuration file loading (YAML/JSON)
• ✅ Client identity generation with subnet constraints
• ✅ Network interface introspection
• ✅ Packet building for all supported protocols
• ✅ Multi-client sender orchestration
• ✅ Error handling and edge cases
• ✅ Dry-run mode and PCAP output

# View coverage report
pytest --cov=fluxgen --cov-report=term-missing

# Generate HTML coverage report
pytest --cov=fluxgen --cov-report=html
open htmlcov/index.html  # macOS
# Or: firefox htmlcov/index.html  # Linux

Contributing

Contributions are welcome! Please follow these guidelines:

1. Fork the repository and create a feature branch
2. Write tests for new functionality
3. Ensure all tests pass: pytest
4. Follow PEP 8 coding style
5. Submit a pull request with clear description

Development Setup

# Clone and setup development environment
git clone <repository-url>
cd fluxgen
python3 -m venv venv
source venv/bin/activate
pip install -r requirements.txt
pip install pytest pytest-cov pytest-mock

# Run tests before committing
pytest --cov=fluxgen

# Install in editable mode for development
pip install -e .

License

This project is provided as-is for educational and testing purposes. Ensure you have proper authorization before using fluxgen on any network.