"Hide books" extension?

[encol]

Hi, is it possible to hide some books that are already on my kindle storage?
I share my kindle with my 9 years old child, and some books i have are not suitable for him.

I think a Kual extension wich crypt some files in documents folder (can gpg be installed?) or simply rename or move them to another folder.

I know that Kual can launch scripts, but is possible to give a password, select from the menu some books and pass these things as parameters for the script? (Or, in general, is it possible to do some sort of input in Kual and pass it to the script?)

Edit: i made an extension for this. See see here and here

[knc1]

Originally Posted by encol

Hi, is it possible to hide some books that are already on my kindle storage?
I share my kindle with my 9 years old child, and some books i have are not suitable for him.

Hide from an adult: Probably
Hide from a nine year old: Not likely

Originally Posted by encol

I think a Kual extension wich crypt some files in documents folder (can gpg be installed?) or simply rename them.

Amazon firmware includes OpenSSL.

Originally Posted by encol

I know that Kual can launch scripts, but is possible to give a password, select from the menu some books and pass them as parameters? (Or, in general, is it possible to do some sort of input in Kual and pass it to the script?)

KUAL does not accept input.

There is a post here about 'faking it' using zsh (zsh is included with the USBnetworking package).

It might be possible to change KUAL to accept input from the 'search bar' - but I don't think anyone has looked into doing that.
Plus - nearly the entire KUAL development team has moved on to other things.

[encol]

Originally Posted by knc1

Hide from an adult: Probably
Hide from a nine year old: Not likely

On the contrary, it is really for this

[Localhorst86]

My idea would be to convert your delicate ebooks to epub format. That way they wont show up in the kindle menu. You can then use librerator or koreader (or the dreaded Duokan) to read those epubs. It's not password locked, though.

[encol]

Originally Posted by knc1

There is a post here about 'faking it' using zsh (zsh is included with the USBnetworking package).

any reference?

Originally Posted by knc1

It might be possible to change KUAL to accept input from the 'search bar' - but I don't think anyone has looked into doing that.

perhaps there is no need to change KUAL. If somewhere in the filesystem is stored the last search done, it can be used as "input textbox": the script who need input can use it (if there is).

Then, if the script recognises the password, it can hide the books that has some sort of "prefix" in the name (previously added by a file manager)

[knc1]

How about this?

Using your command line access (kTerm, ssh, telnet, serial port, etc) -
Make a place for the book list script:

mntroot rw
mv /usr/bin/logThis.sh /usr/bin/logThis.bak
mntroot ro

Make a book listing script (two lines, Unix EoL), such as:

#!/bin/sh
find /mnt/us/documents "-name $@" >/mnt/us/extensions/booklist.txt

USB cable to PC -
Copy the above contents to top of visible storage as the file named:
logThis.sh
Safely remove -
Remove USB cable

Then again from your command line access:

mntroot rw
cp /mnt/us/logThis.sh /usr/bin/logThis.sh
mntroot ro

On the Kindle main screen, tap the search icon -
In the search bar type:
;log hide-me-*

Then (with however you view the USB storage - such as cable to PC) -
You should find (no pun intended) a list of books with the prefix:
'hide-me-'
in the file:
/extensions/booklist.txt

Note:
If you remove the '-name' from inside the quotes of the script, then you can use any set of 'find' commands to create the list.

The 'find' command that ships with 5.6.x and newer firmwares has this set of options:

Usage: find [PATH]... [EXPRESSION]

Search for files. The default PATH is the current directory,
default EXPRESSION is '-print'

EXPRESSION may consist of:
        -follow         Follow symlinks
        -xdev           Don't descend directories on other filesystems
        -maxdepth N     Descend at most N levels. -maxdepth 0 applies
                        tests/actions to command line arguments only
        -mindepth N     Don't act on first N levels
        -name PATTERN   File name (w/o directory name) matches PATTERN
        -iname PATTERN  Case insensitive -name
        -path PATTERN   Path matches PATTERN
        -regex PATTERN  Path matches regex PATTERN
        -type X         File type is X (X is one of: f,d,l,b,c,...)
        -perm NNN       Permissions match any of (+NNN), all of (-NNN),
                        or exactly NNN
        -mtime DAYS     Modified time is greater than (+N), less than (-N),
                        or exactly N days
        -mmin MINS      Modified time is greater than (+N), less than (-N),
                        or exactly N minutes
        -newer FILE     Modified time is more recent than FILE's
        -inum N         File has inode number N
        -user NAME      File is owned by user NAME (numeric user ID allowed)
        -group NAME     File belongs to group NAME (numeric group ID allowed)
        -depth          Process directory name after traversing it
        -size N[bck]    File size is N (c:bytes,k:kbytes,b:512 bytes(def.))
                        +/-N: file size is bigger/smaller than N
        -links N        Number of links is greater than (+N), less than (-N),
                        or exactly N
        -print          Print (default and assumed)
        -print0         Delimit output with null characters rather than
                        newlines
        -exec CMD ARG ; Run CMD with all instances of {} replaced by the
                        matching files
        -prune          Stop traversing current subtree
        (EXPR)          Group an expression

Now that you have your 'search bar, book list maker' -
All you have to do is decide how your going to 'hide' the books.
Note: just moving them out of /documents will hide them from the Kindle reader, but not from the KOreader, reader.

Then, I suppose, we would need to preempt one or more search bar command keys to trigger the hiding and un-hiding action.

= = = =

Note: I have not tested any of the above, I just typed up my first thought.
The above would be one way to create a list of books from a search bar command.

Note 2: There is a very good routine (Argon2) to convert a passphrase (say, entered into the search bar) into a cryptographic key.
https://github.com/janetizzy/phc-win.../tree/autotool
Which I am working on to add autotool and cross-compile support.

Note 3: Moving books into and out of a password protected zip file would probably 'hide' them well enough - especially if using Argon2 for the key generation from a searchbar entered passphrase.

[encol]

Thanks man, i'll try soon

[knc1]

Originally Posted by encol

Thanks man, i'll try soon

That is just the start of what would be a lot of scripting.

no 'zip' utility (or any other password protected archive) -
but openssl enc ... is included with the firmware.
and, that openssl function accepts a passphrase -

I'll see if my Argon2 will cross-compile for ARMel today -
that would be used to generate the cyrpto quality openssl enc passphrase from user input on the search bar.

At the moment, I am thinking to just turn each book into an encrypted, gzip'd file - -
I don't think the Kindle will do anything foolish like try to index or display a *.gz file.

The Argon2 generated passphrase for the openssl enc function will **not** be stored on the Kindle - -
So you will have to enter it into the search bar along with enc/dec command and the desired book.

As each book is processed, it needs to update the booklist.txt file with 'old' and 'new' names (I think that would be easiest - a lot of this is just guess work).

[Cinisajoy]

Originally Posted by encol

Hi, is it possible to hide some books that are already on my kindle storage?
I share my kindle with my 9 years old child, and some books i have are not suitable for him.

I think a Kual extension wich crypt some files in documents folder (can gpg be installed?) or simply rename or move them to another folder.

I know that Kual can launch scripts, but is possible to give a password, select from the menu some books and pass these things as parameters for the script? (Or, in general, is it possible to do some sort of input in Kual and pass it to the script?)

Easier solution,
Can you just delete the books off the kindle temporarily and forget the wifi password?

[knc1]

Originally Posted by Cinisajoy

Easier solution,
Can you just delete the books off the kindle temporarily and forget the wifi password?

9 year olds probably know how to undelete files from FAT-32

[Cinisajoy]

The only real way I see for a 9 year old not to find the books is buy him his own kindle and make a special account with Amazon where he can only read books you find suitable.

How much do you trust your son to do what you say?

[Yolina]

Isn't that what 'Kindle for kids' profiles are there for in the settings?

[Cinisajoy]

Originally Posted by Yolina

Isn't that what 'Kindle for kids' profiles are there for in the settings?

Thanks I couldn't remember what it was called.

[knc1]

Originally Posted by Yolina

Isn't that what 'Kindle for kids' profiles are there for in the settings?

Good point.
I should just **use** my Kindles more than I do, rather than look at the insides of them.

Ah, but other people have asked about keeping encrypted information on their Kindle, so we gave them a start towards a solution with this thread.

[Cinisajoy]

Originally Posted by knc1

Good point.
I should just **use** my Kindles more than I do, rather than look at the insides of them.

Ah, but other people have asked about keeping encrypted information on their Kindle, so we gave them a start towards a solution with this thread.

Keeping encrypted info from your mother is probably easy. Keeping encrypted info from a child almost impossible.
Most of them have been using devices since before they could talk.