Simple commands that allows you to create Docker image file from existing Docker image.
For ease of use let’s create alias for reverse engineering command:
Preparation:
alias dfimage="docker run -v /var/run/docker.sock:/var/run/docker.sock --rm alpine/dfimage"
Reverse engineering:
Now we can use alias like that:
dfimage -sV=1.40 hello-world
Result:
Information about structure Dockerfile of existing image.
Analyzing hello-world
Docker Version: 18.06.1-ce
GraphDriver: overlay2
Environment Variables
|PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
Image user
|User is root
Potential secrets:
Dockerfile:
CMD ["/hello"]