j-keck / Lsleases

• lsleases - list dynamic assigned ip addresses in your network

lsleases captures broadcast 'DHCP request' datagrams from any device \ (pc, laptop, virtual machine, phone, raspberry, esp32, ...) with dynamic ip addresses in your local network.

You can list the captured ip addresses to lookup an assigned ip for a device.

/For more information, check the [[docs/manual.org][Manual]]./

• Usage

1.) install lsleases - see [[#installation][Installation]]

2.) re-plug / start-up any device with a dynamic ip address

3a.) list captured devices

#+BEGIN_EXAMPLE [email protected]:~ ⟩ lsleases Ip Mac Host 192.168.1.152 80:d0:9b:xx:xx:xx android-6298296f6184995a 192.168.1.122 b8:27:eb:xx:xx:xx raspberrypi 192.168.1.155 5c:cf:7f:xx:xx:xx NODE-931BFD #+END_EXAMPLE

3b.) or if you start lsleasesd with the '-webui' option, you can open your browser at http://127.0.0.1:9999 to access the integrated webapp.

[[./docs/webui-screenshot.png]]

/You can use lsleases as a go library in your own programs: [[#lsleases-go-library][lsleases go library]]/

• Installation

/I will provide standalone binaries for each platform in the coming days./

! If no leases are captured, make sure your firewall has port 67 (DHCP) open !

#+BEGIN_SRC shell :eval no sudo iptables -I INPUT -p udp --dport 67 -j ACCEPT #+END_SRC

check the [[docs/manual.org][Manual]] for a description.

• [[#debian--ubuntu][Debian / Ubuntu]]
• [[#redhat--fedora][Redhat / Fedora]]
• [[#windows][Windows]]
• [[#osx][OSX]]
• [[#freebsd][FreeBSD]]
• [[#build-from-source-client--server][Build from source (client / server)]]
• [[#build-from-source-standalone][Build from source (standalone)]]

*** Debian / Ubuntu

1.) download the .deb package from [[http://github.com/j-keck/lsleases/releases/latest]]

2.) install the package sudo dpkg -i lsleases--.deb

3.) activate the service sudo systemctl enable lsleasesd

4.) start the daemon sudo systemctl start lsleasesd

*** RedHat / Fedora

1.) download the .rpm package from [[http://github.com/j-keck/lsleases/releases/latest]]

2.) install the package sudo rpm -i lsleases--.rpm

3.) activate the service sudo systemctl enable lsleasesd

4.) start the daemon sudo systemctl start lsleasesd

*** Windows

I provide two packages for windows:

• lsleases---windows-installer.exe
• lsleases---windows-standalone.zip

check [[docs/manual-windows.org][Windows Manual]] for more information.

1.) download the package from [[http://github.com/j-keck/lsleases/releases/latest]]

2.) install per installer or unzip the standalone package

*** OSX

1.) download the lsleases---osx-standalone.zip package from [[http://github.com/j-keck/lsleases/releases/latest]]

2.) unpack the zip archive and go into the lsleases directory

3.) execute ./capture-leases.sh

*** FreeBSD

1.) download the lsleases--amd64-freebsd.txz package from [[http://github.com/j-keck/lsleases/releases/latest]]

2.) install the package sudo pkg install lsleases--amd64-freebsd.txz

3.) allow unprivileged users open ports less than 1024 (lsleasesd runs as user nobody) #+BEGIN_SRC shell :eval no echo net.inet.ip.portrange.reservedhigh=0 | sudo tee -a /etc/sysctl.conf sudo service sysctl restart #+END_SRC

4.) activate the service sudo sysrc lsleasesd_enable=YES

5.) start the daemon sudo service lsleasesd start

*** Build from source (client / server)

1.) fetch the server #+BEGIN_SRC shell :eval no go get -u github.com/j-keck/lsleases/cmd/lsleasesd #+END_SRC

2.) start the server #+BEGIN_SRC shell :eval no sudo $GOPATH/bin/lsleasesd & #+END_SRC

3.) fetch the client #+BEGIN_SRC shell :eval no go get -u github.com/j-keck/lsleases/cmd/lsleases #+END_SRC

4.) run the client #+BEGIN_SRC shell :eval no $GOPATH/bin/lsleases -w #+END_SRC

see the [[/docs/manual.org#build-from-source][Manual]] for more information.

*** Build from source (standalone)

For a quick test you can use the standalone mode without the server component. In this mode it does not run in the background, has no cache and supports no webui.

1.) fetch the client #+BEGIN_SRC shell :eval no go get -u github.com/j-keck/lsleases/cmd/lsleases #+END_SRC

2.) run the client in the standalone mode #+BEGIN_SRC shell :eval no sudo $GOPATH/bin/lsleases -s #+END_SRC

see the [[/docs/manual.org#build-from-source][Manual]] for more information.

• lsleases go library

You can use lsleases as a go library in your own programs. For example to trigger any custom action on device discovery.

#+BEGIN_SRC go :tangle examples/simple-sniffer.go :mkdirp yes :eval no package main

import "github.com/j-keck/lsleases/pkg/sniffer" import "github.com/j-keck/lsleases/pkg/config" import "github.com/j-keck/plog"

func main() { // create a logger instance log := plog.GlobalLogger().Add(plog.NewDefaultConsoleLogger())

// create the sniffer with the default configuration cfg := config.NewDefaultConfig() sniffer := sniffer.NewSniffer(cfg)

// subscribe to DHCP leases events and log the events go func() { leasesC := sniffer.Subscribe(10) for { lease := <-leasesC log.Infof("new lease: %s", lease.String()) } }()

if err := sniffer.Start(); err == nil { log.Info("sniffing ... - hit to abort -") select {} } else { panic(err) } } #+END_SRC

#+BEGIN_SRC shell :eval no GO111MODULE=on sudo go run examples/simple-sniffer.go #+END_SRC

• Changelog

see [[docs/changelog.org][Changelog]]