New version of DRM removal tools ("DeDRM") - Page 50

davidfor · 09-17-2016, 01:06 AM

Quote:

Originally Posted by 13xforever

I can confirm that Kobo Desktop 4.0.5579 did not change the content encryption scheme.

The problem most probably is in Obok itself, because my own tool works just fine.

But it has change an option used in creating the database. That means the current version of Obok cannot read the database on Wndows machines. Fixing that part is easy. How the other part is wrong, I don't know as it works with the older database and books.

Quote:

PS: on the side note, there's now a new Books.sqlite database in program data folder, which is encrypted. No idea what it's for.

I don't know what is in it, but I'm pretty sure it isn't being used for this. It might be were the Overdrive loan details are stored.

13xforever · 09-23-2016, 02:23 AM

Quote:

Originally Posted by davidfor

But it has change an option used in creating the database.

Not sure what you mean by this. I even cleaned up the app data and re-created everything from scratch, Kobo Desktop 4.0 creates the same DB as after migrating from 3.19. DbVersion is the same, the structure is mostly the same as it was since 3.17. Same content_keys, same master key generation function.

davidfor · 09-23-2016, 04:08 AM

Quote:

Originally Posted by 13xforever

Not sure what you mean by this. I even cleaned up the app data and re-created everything from scratch, Kobo Desktop 4.0 creates the same DB as after migrating from 3.19. DbVersion is the same, the structure is mostly the same as it was since 3.17. Same content_keys, same master key generation function.

Kobo change the journal mode from "delete" to "wal". This is supported with SQLite 3.7 or later. Obok, the KoboTouch driver and all the other calibre plugins were using sqlite3 to access the database. On Windows, sqlite3 was built with a SQLite 3.6 library. When calibre tried to read the database, it gave an error because sqlite3 could not handle the WAL option. The error suggested the file was either encrypted or not a database. On the other platforms sqlite3, uses 3.7, so there were no problems.

I changed all the KoboTouch driver and other plugins to use apsw as this uses a later SQLite library and is what calibre uses for all of it's own database access. After making the appropriate changes to Obok, the books could be seen, but the DRM could not be removed. It could for a 3.19 database on one of my devices.

I can't check right now, are you sure it is the same DbVersion as 3.19? From memory, 3.19 would have been 126 or 127. 4.0 should be 129. That is what the devices use, and the desktop application is usually the same. I'll check when I get home, but there is something strange here.

What OS are you using?

Edit:

Just looked, the version of the desktop application is 4.0.5579. The database has DbVersion of 129. And I still have 3.19 on another machine. That has DbVersion of 125.

13xforever · 09-23-2016, 07:11 AM

Quote:

Originally Posted by davidfor

Kobo change the journal mode from "delete" to "wal".

Ah, I saw that, and I use very old SQLite version too, so I didn't think that was a problem. But that doesn't relate to anything but Obok.

Quote:

Originally Posted by davidfor

I can't check right now, are you sure it is the same DbVersion as 3.19? From memory, 3.19 would have been 126 or 127. 4.0 should be 129.

3.19 desktop is version 125, I believe. I have some backups, so I can double-check. And yes, 4.0 upgrades to and creates db version 129.

Quote:

Originally Posted by davidfor

What OS are you using?

Windows.

davidfor · 09-23-2016, 08:53 AM

Quote:

Originally Posted by 13xforever

Ah, I saw that, and I use very old SQLite version too, so I didn't think that was a problem. But that doesn't relate to anything but Obok.

Well, you must be using an SQLite version that supports WAL or else I don't think you would be able to read the database at all.

But, I've just worked out what I've done wrong and the only thing I can say is

pdurrant · 09-23-2016, 09:05 AM

Quote:

Originally Posted by davidfor

Well, you must be using an SQLite version that supports WAL or else I don't think you would be able to read the database at all.

But, I've just worked out what I've done wrong and the only thing I can say is

That sounds like good news for the rest of us!

Terisa de morgan · 09-23-2016, 09:06 AM

Quote:

Originally Posted by pdurrant

That sounds like good news for the rest of us!

I think so, I know the feeling....

Cex · 10-06-2016, 04:38 AM

Quote:

Originally Posted by davidfor

Kobo change the journal mode from "delete" to "wal". This is supported with SQLite 3.7 or later. Obok, the KoboTouch driver and all the other calibre plugins were using sqlite3 to access the database. On Windows, sqlite3 was built with a SQLite 3.6 library. When calibre tried to read the database, it gave an error because sqlite3 could not handle the WAL option. The error suggested the file was either encrypted or not a database. On the other platforms sqlite3, uses 3.7, so there were no problems.

I changed all the KoboTouch driver and other plugins to use apsw as this uses a later SQLite library and is what calibre uses for all of it's own database access. After making the appropriate changes to Obok, the books could be seen, but the DRM could not be removed. It could for a 3.19 database on one of my devices.

Thank you for the tip!

I bought a book from Kobo and the Obok tool raised the error regarding the uncompatible or encrypted database.
I tried to modify OBOK.PY file by changing 'sqlite3' by 'apsw' and 'fetchone' by 'next', but know the plugin complains about the database not containing valid keys...may I need more changes to use APSW? (I asume the keys are there, but the use os 'apsw' makes the script fail, maybe because the returned data when using 'apsw' is not the same as 'sqlite3').

Yes, I know I can install and use ADE, but I would prefer to have the obok plugin fixed.

I would appreciate some guidance on what changes between 'sqlite3' and 'apsw' besides 'next' instead of 'fetchone', and 'Connection' instead of 'connect'.

Thank you!

HarryT · 10-06-2016, 04:46 AM

Quote:

Originally Posted by Cex

Thank you for the tip!

I bought a book from Kobo and the Obok tool raised the error regarding the uncompatible or encrypted database.
I tried to modify OBOK.PY file by changing 'sqlite3' by 'apsw' and 'fetchone' by 'next', but know the plugin complains about the database not containing valid keys...may I need more changes to use APSW? (I asume the keys are there, but the use os 'apsw' makes the script fail, maybe because the returned data when using 'apsw' is not the same as 'sqlite3').

Yes, I know I can install and use ADE, but I would prefer to have the obok plugin fixed.

I would appreciate some guidance on what changes between 'sqlite3' and 'apsw' besides 'next' instead of 'fetchone', and 'Connection' instead of 'connect'.

Thank you!

It is against our site policy to provide detailed help with DRM removal. Please don't ask again.

Thanks.

Cex · 10-06-2016, 04:48 AM

OK, I was asking how to fix a script, not how to remove DRM, but I'll avoid asking again.

Sorry for this.

Lynx-lynx · 10-06-2016, 05:12 AM

Cex, a fix has been devised. We've asked apprentice harper to post it. Keep an eye out on his github site.

Cex · 10-06-2016, 06:00 AM

Quote:

Originally Posted by Lynx-lynx

Cex, a fix has been devised. We've asked apprentice harper to post it. Keep an eye out on his github site.

Thank you. Much appreciated.
I apologize again for asking what I shouldn't have asked.

HarryT · 10-06-2016, 06:17 AM

No apologies needed!

davidfor · 10-06-2016, 06:33 AM

Quote:

Originally Posted by Cex

I would appreciate some guidance on what changes between 'sqlite3' and 'apsw' besides 'next' instead of 'fetchone', and 'Connection' instead of 'connect'.

For your, reference if you ever need to do an sqlite3 to apsw conversion, the two other things I can think of are:

- cursor.commit becomes cursor.execute("commit"). But removed all these as there were no actual transactions.

- If there is only one column in a select statement, the result will be a value rather than an array.

Cex · 10-06-2016, 08:12 AM

Quote:

Originally Posted by davidfor

For your, reference if you ever need to do an sqlite3 to apsw conversion, the two other things I can think of are:

- cursor.commit becomes cursor.execute("commit"). But removed all these as there were no actual transactions.

- If there is only one column in a select statement, the result will be a value rather than an array.

I think this is what I needed.
Thank you so much!

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10-06-2016, 04:48 AM	#745
Cex Enthusiast Posts: 29 Karma: 13132 Join Date: Jul 2015 Location: Spain Device: Glo; Glo HD; PW2; Voyage	OK, I was asking how to fix a script, not how to remove DRM, but I'll avoid asking again. Sorry for this.

10-06-2016, 05:12 AM	#746
Lynx-lynx Treachery of images ... Posts: 4,149 Karma: 94320195 Join Date: May 2012 Location: Australia Device: Sony 650, Kobo Glo, H2O, Aura One, Forma, Libra 2, Libra Colour	Cex, a fix has been devised. We've asked apprentice harper to post it. Keep an eye out on his github site.

10-06-2016, 06:17 AM	#748
HarryT eBook Enthusiast Posts: 85,560 Karma: 93980341 Join Date: Nov 2006 Location: UK Device: Kindle Oasis 2, iPad Pro 10.5", iPhone 6	No apologies needed!