Setting Up a Metasploit Development Environment

^{The shortlink to this wiki page is https://r-7.co/MSF-DEV}

This is a guide for setting up a developer environment to contribute modules, documentation, and fixes to the Metasploit Framework. If you just want to use Metasploit for legal, authorized hacking, we recommend instead you:

• Install the open-source Omnibus installer, or
• Use the pre-installed Metasploit on Kali Linux or Parrot Linux.

If you want to contribute to Metasploit, start by reading our CONTRIBUTING.md, then follow the rest of this guide.

Assumptions

• You have installed an apt-based Linux environment, such as Ubuntu or Kali.
• You have created a GitHub account and associated an public ssh key with it.
• You have familiarity with Git and Github, or have completed the Github bootcamp.
• For optional database and REST API functionality, you will need regular user account that is not root.

This guide has details for setting up both Linux and Windows.

Install dependencies

1. Open a terminal on your Linux host and set up Git, build tools, and Ruby dependencies:

sudo apt update && sudo apt install -y git autoconf build-essential libpcap-dev libpq-dev zlib1g-dev libsqlite3-dev

If you are running a Windows machine

1. Install chocolatey
2. Install Ruby x64 with DevKit
3. Install pcaprub dependencies from your cmd.exe terminal:

powershell -Command "[System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true} ; [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; (New-Object System.Net.WebClient).DownloadFile('https://www.winpcap.org/install/bin/WpdPack_4_1_2.zip', 'C:\Windows\Temp\WpdPack_4_1_2.zip')"

choco install 7zip
7z x "C:\Windows\Temp\WpdPack_4_1_2.zip" -o"C:\"

4. Install a version of PostgreSQL:

choco install postgresql12

Set up your local copy of the repository

You will need to use Github to create a fork for your contributions and receive the latest updates from our repository.

1. Login to Github and click the "Fork" button in the top-right corner of the metasploit-framework repository.

2. Create a git directory in your home folder and clone your fork to your local machine:

export GITHUB_USERNAME=YOUR_USERNAME_FOR_GITHUB
export GITHUB_EMAIL=YOUR_EMAIL_ADDRESS_FOR_GITHUB
mkdir -p ~/git
cd ~/git
git clone git@github.com:$GITHUB_USERNAME/metasploit-framework
cd ~/git/metasploit-framework

3. If you encounter a "permission denied" error on the above command, research the error message. If there isn't an explicit reason given, confirm that your Github SSH key is configured correctly. You will need to associate your public SSH key with your GitHub account, otherwise if you set up a SSH key and don't associate it with your GitHub account, you will receive this "permission denied" error.

4. To receive updates, you will create an upstream-master branch to track the Rapid7 remote repository, alongside your master branch which will point to your personal repository's fork:

git remote add upstream git@github.com:rapid7/metasploit-framework.git
git fetch upstream
git checkout -b upstream-master --track upstream/master

5. Configure your Github username, email address, and username. Ensure your user.email matches the email address you registered with your Github account.

git config --global user.name "$GITHUB_USERNAME"
git config --global user.email "$GITHUB_EMAIL"
git config --global github.user "$GITHUB_USERNAME"

6. Set up msftidy to run before each git commit and after each git merge to quickly identify potential issues with your contributions:

cd ~/git/metasploit-framework
ln -sf ../../tools/dev/pre-commit-hook.rb .git/hooks/pre-commit
ln -sf ../../tools/dev/pre-commit-hook.rb .git/hooks/post-merge

Install Ruby

Linux distributions do not ship with the latest Ruby, nor are package managers routinely updated. Additionally, if you are working with multiple Ruby projects, each one has dependencies and Ruby versions which can start to conflict. For these reasons, it is advisable to use a Ruby manager.

You could just install Ruby directly (eg. sudo apt install ruby-dev), but you may likely end up with the incorrect version and no way to update. Instead, consider using one of the many different Ruby environment managers available. The Metasploit team prefers rbenv and rvm (note that rvm does require a re-login to complete).

Regardless of your choice, you'll want to make sure that, when inside the ~/git/metasploit-framework directory, you are running the correct version of Ruby:

$ cd ~/git/metasploit-framework
$ cat .ruby-version 
3.0.2
$ ruby -v
ruby 3.0.2p107 (2021-07-07 revision 0db68f0233) [x86_64-linux]

Note: the Ruby version is likely to change over time, so don't rely on the output in the above example. Instead, confirm your ruby -v output with the version number listed in the .ruby-version file.

If the two versions don't match, restart your terminal. If that does not work, consult the troubleshooting documentation for your Ruby environment manager. Unfortunately, troubleshooting the Ruby environment is beyond the scope of this document, but feel free to reach out for community support using the links at the bottom of this document.

Install Gems

Before you run Metasploit, you will need to update the gems (Ruby libraries) that Metasploit depends on:

cd ~/git/metasploit-framework/
gem install bundler
bundle install

If you encounter an error with the above command, refer to the bundle output and search for the error message along with the name of the gem that failed. Likely, you'll need to apt get install a dependency that is required by that particular gem.

Congratulations! You have now set up a development environment and the latest version of the Metasploit Framework. If you followed this guide step-by-step, and you ran into any problems, it would be super great if you could open a new issue so we can either help you, or, more likely, update the docs.

Optional: Set up the REST API and PostgreSQL database

The following optional section describes how to manually install PostgreSQL and set up the Metasploit database. Alternatively, use our Omnibus installer which handles this more reliably.

1. Confirm that the PostgreSQL server and client are installed:

sudo apt update && sudo apt-get install -y postgresql postgresql-client
sudo service postgresql start && sudo update-rc.d postgresql enable

2. Ensure that you are not running as the root user.

3. Initialize the Metasploit database:

cd ~/git/metasploit-framework
./msfdb init

4. If you receive an error about a component not being installed, confirm that the binaries shown are in your path using the which and find commands, then modifying your $PATH environment variable. If it was something else, open a new issue to let us know what happened.

5. If the msfdb init command succeeds, then confirm that the database is accessible to Metasploit:

$ ./msfconsole -qx "db_status; exit"

Congratulations! You have now set up the Metasploit Web Service (REST API) and the backend database.

Optional: Tips to speed up common workflows

The following section is optional but may improve your efficiency.

Making sure you're in the right directory to run msfconsole can become tedious, so consider using the following Bash alias:

echo 'alias msfconsole="pushd $HOME/git/metasploit-framework && ./msfconsole && popd"' >> ~/.bash_aliases

Consider generating a GPG key to sign your commits. Read about why and how. Once you have done this, consider enabling automatic signing of all your commits with the following command:

cd *path to your cloned MSF repository on disk*
git config commit.gpgsign true

Developers tend to customize their own git aliases to speed up common commands, but here are a few common ones:

[alias]
# An easy, colored oneline log format that shows signed/unsigned status
nicelog = log --pretty=format:'%Cred%h%Creset -%Creset %s %Cgreen(%cr) %C(bold blue)<%aE>%Creset [%G?]'

# Shorthand commands to always sign (-S) and always edit the commit message.
m = merge -S --no-ff --edit
c = commit -S --edit

# Shorthand to always blame (praise) without looking at whitespace changes
b= blame -w

If you plan on working with other contributor's pull requests, you may run the following script which makes it easier to do so:

tools/dev/add_pr_fetch.rb

After running the above script, you can checkout other pull requests more easily:

git fetch upstream
git checkout fixes-to-pr-12345 upstream/pr/12345

If you're writing test cases (which you should), then make sure rspec works:

rake spec

You should see over 9000 tests run, mostly resulting in green dots, a few in yellow stars, and no red errors.

Great! Now what?

We're excited to see your upcoming contributions of new modules, documentation, and fixes! Check out our wiki documentation and, if you're looking for inspiration, keep an eye out for newbie-friendly pull requests and issues. Please submit your new pull requests and reach out to us on Slack for community help.

Finally, we welcome your feedback on this guide, so feel free to reach out to us on Slack or open a new issue. For their significant contributions to this guide, we would like to thank @kernelsmith, @corelanc0d3r, and @ffmike.