8. Under The Covers

Like most other consumer-level NAS devices on the market, the StorCenter was clearly running Linux. A network port-scan of the device turned up no interesting open ports, but a fingerprint scan identified the TCP/IP stack as being from a Linux kernel. Connecting to the UPnP server port manually from a Telnet window gave me the following string:

To verify my findings, I found that Iomega included Linux 2.6.12 and other GPL source code on the installation CD. The Linux configuration file included indicates that a Iomega's documentation, it appears that the StorCenter has 64 MB of RAM, and is running on a EXT2 file system. (This was changed over to XFS as of firmware version v1.27.) The 250 GB model I tested had 8 MB of cache, while the 160 GB model has 2 MB.

While I was browsing the folder sharing options, I noticed the following parameter tacked on to the end of the URL: "list_dir=/nethdd". Thinking that perhaps changing it would allow me to get some more visibility into the operation of the system, I manually removed the "nethdd" portion and re-submitted. Bingo! I was rewarded with a display of the top-level directory structure of the operating system, shown in Figure 17. Using this menu, I was able to share the operating system directories as well as the normal data directories.

Figure 17: Directory listing via simple modified URL

Browsing through the read-only directories showed me a standard Linux system with PowerPC binaries and fairly heavy use of busybox for utilities and Samba for file sharing; this is a pretty standard combination with this type of device.

To check out what optional capabilities were provided in the busybox toolkit, I copied it over to my Power PC based KuroBox and verified that it would run there. Running it showed me that it didn't have a Telnet daemon included, which might have given me the ability to get a command shell on the running box. I suspect that with more effort, a user willing to risk his warranty could figure out a way to add custom code for additional functionality.