geekmaster's data.tar.gz and K4NT FW 4.1.1

[Skeeve]

Hi!

Yesterday I wanted to activate the screensavers without jailbreaking my K4NT. I already was told in another thread that it's not possible, but still do not understand why it shouldn't be possible. So maybe someone can explain to me?

Here is what I understand:

There is a data.tar.gz file which the Kindle will extract upon boot. The content goes to /var/local/system and is the mntus.param file. This one should be executed by the kindle.

I looked into the file and tried to understand it.

MNTUS_PART_START=16
MNTUS_PART_OFFSET=8192
MNTUS_FATSIZE=32

## use actual size from fdisk (minus 8KB offset):
let MNTUS_PART_SIZE="`fdisk -l|grep FAT32|awk '{print $4}'`-8"

## if invalid size (normal during main boot),
## then use known size for each serial number:
if [ $MNTUS_PART_SIZE -lt 1000000 ]; then
  SER4=`grep Serial /proc/cpuinfo|cut -b12-15`
  case $SER4 in
  "B004"|"B005"       ) MNTUS_PART_SIZE=3567224 ;; # DX
  "B006"|"B008"|"B00A") MNTUS_PART_SIZE=3205336 ;; # K3
  "B009"              ) MNTUS_PART_SIZE=3510232 ;; # DXG
  "B00E"              ) MNTUS_PART_SIZE=1423352 ;; # K4 (mini)
  "B00F"|"B011"       ) MNTUS_PART_SIZE=3377144 ;; # K5 (touch)
  *)
    ## unknown size, exit may erase USB Drive!
    eips -c
    eips  5 28 "This $SER4 Kindle is not supported..."
    eips 10 30 "(${MNTUS_PART_SIZE}KB USB Drive)"
    eips  7 32 "Removing installer files..."
    sleep 8
    ;;                   
  esac
fi

mount -o rw,noatime,nodiratime,offset=8192 /dev/mmcblk0p4 /mnt/us
[ -f /mnt/us/RUNME.sh -a ! -f /mnt/us/RUNME.done ] && (
  touch /mnt/us/RUNME.done
  sh /mnt/us/RUNME.sh 2>&1 >/mnt/us/RUNME.out
)
umount -d /mnt/us

I'm not sure whether or not the file is really executed. If it were I should have a RUNME.done, which I do not get.

So the question is, whether the file gets executed or if the file simply refrains from executing RUNME.sh because the preliminary tests fail. But wouldn't I see the messages printed with eips then?

Could someone please help me understand this? I especially do not understand why jailbreaking should work (as I'm told), when it's using the same approach, namely putting mntus.param into the filesystem.

Another question is: Does the mntu.params stay on the device? Have I now lost my original mntu.params?

[Skeeve]

I experimented a bit an added this to the top of the mntu.params file:

eips -c
eips 5 28 "Starting..."
sleep 8
eips 5 30 "wait 8 secs more..."
sleep 8

I thought this would clear the screen, and then display "Starting...", wait 8 seconds, display "wait 8 secs more...", wait again and then continue.

Well - It didn't. My Kindle booted as normal.

[icantbebothered]

To install tge screensaver hack you need to run a non amazon install package. Which is noincluding llwed without the jailbreak. So jailbreak your kindle.

[Skeeve]

Originally Posted by icantbebothered

To install tge screensaver hack you need to run a non amazon install package. Which is noincluding llwed without the jailbreak. So jailbreak your kindle.

Thanks for your reply but how does this answer my question "I especially do not understand why jailbreaking should work (as I'm told), when it's using the same approach, namely putting mntus.param into the filesystem."

BTW: Which package would I need to install? I just wanted access to the /opt/amazon/screen_saver/600x800 directory. I don't want this "Last Cover" screensaver.

[knc1]

Originally Posted by Skeeve

Thanks for your reply but how does this answer my question "I especially do not understand why jailbreaking should work (as I'm told), when it's using the same approach, namely putting mntus.param into the filesystem."

The link to where you where told that please.

[Skeeve]

Originally Posted by knc1

The link to where you where told that please.

https://www.mobileread.com/forums/sho...&postcount=130

Linking to https://wiki.mobileread.com/wiki/Kindle4NTHacking

I looked into the data.tar.gz mentioned there.

[knc1]

Originally Posted by Skeeve

https://www.mobileread.com/forums/sho...&postcount=130

Linking to https://wiki.mobileread.com/wiki/Kindle4NTHacking

I looked into the data.tar.gz mentioned there.

And you want to modify that process from installing the jailbreak certificate to install and/or modify other files?

[NiLuJe]

There's a reason we use a specific process, so unless you want to understand the inner-workings of the jb for fun, I'd recommend sticking to it .

[knc1]

Originally Posted by NiLuJe

There's a reason we use a specific process, so unless you want to understand the inner-workings of the jb for fun, I'd recommend sticking to it .

Agreed.
Just was trying to be certain I understood the question.

The developers here have put in years of work to establish and maintain our system that re-uses Amazon's GUI Kindle Update tool.

[Skeeve]

I want to understand also for the fun of it. And I feel ashamed a bit as I missed the ENABLE_DIAGS part Sorry!

But anyhow: I get the message that 9023 is not supported. "-8KB USB Drive"

[NiLuJe]

@Skeeve:

What message? When/where/how?

[Skeeve]

The message produced by this part of the script:

  *)
    ## unknown size, exit may erase USB Drive!
    eips -c
    eips  5 28 "This $SER4 Kindle is not supported..."
    eips 10 30 "(${MNTUS_PART_SIZE}KB USB Drive)"
    eips  7 32 "Removing installer files..."
    sleep 8
    ;;

[twobob]

script was written long before your serial type existed. Hack it in there...?
Fairly sure they fixed that hole on the 2013 models but cant hurt to try...


"9023" ) MNTUS_PART_SIZE=1423352 ;; # K4 (newbie)

obviously you would have to CHECK the part size is still the same on the newer k4 device (I only have an older one)

Anyone? check that?

[NiLuJe]

Also, please use the proper script from the K4 JailBreak, it's much, much more resilient to this type of thing .

[Skeeve]

Thanks for all your patience with me.

I finally followed the advices and now I have a jailbroken Kindle and my son as a screensaver picture.

I also added an
ln -s /opt/amazon/screen_saver/600x800_ /mnt/us/screensaver_orig
to the runme.sh, but this part seemed not to have worked. I think I'll need another "jailbreak run" to actually copy over the original screensaver pictures, should I eally want them.