Introduction to krew
About me
Rewanth Tammana is a security ninja, open-source contributor, independent consultant & SME at Uptycs. Previously, Senior Security Architect at Emirates NBD. Passionate about DevSecOps, Application, and Container Security. Added 17,000+ lines of code to Nmap. Holds industry certifications like CKS, CKA, etc.
About me
https://twitter.com/rewanthtammana
Speaker & trainer at international security conferences worldwide including Black Hat, Defcon, Hack In The Box (Dubai and Amsterdam), CRESTCon UK, PHDays, Nullcon, Bsides, CISO Platform, null chapters and multiple others.
About me
https://linkedin.com/in/rewanthtammana
One of the MVP researchers on Bugcrowd (2018) and identified vulnerabilities in several organizations. Published an IEEE research paper on an offensive attack in Machine Learning and Security. Also, part of the renowned Google Summer of Code program.
Introduction to krew
Krew is the plugin manager for kubectl CLI.
Krew helps you:
- discover kubectl plugins
- install them on your machine
- and keep the installed plugins up-to-date.
Kubernetes is complex
Discover krew plugins
kubectl krew search
Using krew plugins
kubectl krew install $pluginname
kubectl krew uninstall $pluginname
Sample plugin outline
Switching namespace
kubectl config set-context --current --namespace=$namespace
Lengthy 🫤🫤
Simple plugin
Let's create a plugin to switch namespace with ease
kubectl ns $namespace
End goal ⏬
Simple plugin
Why?
A simple bash script can achieve the above result.
Why write code and make it complex?
Why?
For advanced use cases. Visualization, sniffing network traffic, exploring other Kubernetes components, complex operations, etc.
My plugins
Kubectl whisper secrets
https://github.com/rewanthtammana/kubectl-whisper-secret
kubectl whisper-secret generic my-secret --from-literal key1
Enter value for key1:
secret/my-secret created
More plugins
My personal favorite
Lists the users who can perform certain operation on specific resource
kubectl who-can get po
kubectl who-can '*' po
Conclusion
Simple interpretation
| Platform | Plugin Manager |
|---|---|
| Ubuntu | Apt/Snap |
| CentOS | Yum |
| MacOS | Brew |
| Kubectl | Krew |