You need to build it from the source code. [later: I was mistaken. Binaries are available. See @deLemere’s post under this one.] There are links to Dustin’s ectool web pages (for crude instructions) and his git repo in this thread. I’ve not actually built it myself (although I understand the process).
I’ve been following this thread for a couple of years. The tool’s capability, build process and compatibility gotchas are explored in a lot of detail. If you’re thinking of building it yourself, grab a beverage and start reading from the first post.
If you summarise your system (FW model, distro and kernel version) someone who’s built it for a similar system might be willing to help you avoid any of the bumps they found in the road.
Dino
edit: corrected a misunderstanding for future readers.