@geekmaster: SquashFS appears to drop compatibility at each major release.
So mounting it is going to take a tremendously old kernel.
On the other hand, you should be able to unpack it w/ unsquashfs from squashfs-tools 3.2.
(I'm basing that on the version slots available on Gentoo).
Code:
* sys-fs/squashfs-tools
Available versions:
(3.0) 3.2_p2
(3.1) 3.4
(0) 4.3 (~)4.3-r1
{lz4 lzma lzo xattr +xz}
Homepage: http://squashfs.sourceforge.net
Description: Tool for creating compressed filesystem type squashfs