Sorry I didn't want to bother you
For now I downloaded KindleTool
Code:
$ ./kindletool version
./kindletool (KindleTool) v1.6.4 built by niluje@ajulutsikael on Gentoo with GCC 4.9.2 on May 7 2015 @ 22:16:21 against libarchive 3.1.2 & nettle 3.1.1
Obtained the root password and downloaded the update file (twice just in case

)
Code:
$ sha256sum *.bin
6be62d30df26894b08083dbc55d23774756710c3a44c9a1d0075dd02d12090c9 update_kindle_5.6.1.1_b.bin
6be62d30df26894b08083dbc55d23774756710c3a44c9a1d0075dd02d12090c9 update_kindle_5.6.1.1.bin