Kindle Paperwhite 5.16.2.1.1 - DeDRM fails to decrypt books

[fliker09]

Ubuntu 24.04. Calibre 5.44 (yeah, old, but still works fine). Firmware version is in the subject line. Till February it all worked fine with noDRM 10.0.9. Starting with March it broke :-( Here is the log:

Gather KFX-ZIP (from KFX Input) 2.30.0: Importing /media/alex/Kindle/documents/Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx
Gather KFX-ZIP (from KFX Input): Gathered 5 file(s) as /tmp/calibre_5.44.0_tmp_rzljagg1/0kc7n144.kfx-zip
DeDRM v10.0.9: Trying to decrypt 0kc7n144.kfx-zip
Decrypting KFX-ZIP ebook: 0kc7n144
Found 1 keys to try after 1.5 seconds
Decrypting KFX DRM voucher: voucher
Traceback (most recent call last):
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 105, in decrypt_voucher
    voucher.parse()
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1416, in parse
    _assert(self.envelope.next() == TID_STRUCT and str.startswith(self.envelope.gettypename(), "com.amazon.drm.VoucherEnvelope@"),
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 124, in _assert
    raise Exception(msg)
Exception: Unknown type encountered in envelope, expected VoucherEnvelope
Traceback (most recent call last):
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 105, in decrypt_voucher
    voucher.parse()
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1416, in parse
    _assert(self.envelope.next() == TID_STRUCT and str.startswith(self.envelope.gettypename(), "com.amazon.drm.VoucherEnvelope@"),
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 124, in _assert
    raise Exception(msg)
Exception: Unknown type encountered in envelope, expected VoucherEnvelope
DeDRM v10.0.9: Failed to decrypt with error: Failed to decrypt KFX DRM voucher with any key
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 950, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 204, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 68, in processBook
    self.decrypt_voucher(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 112, in decrypt_voucher
    raise Exception("Failed to decrypt KFX DRM voucher with any key")
Exception: Failed to decrypt KFX DRM voucher with any key
DeDRM v10.0.9: Looking for new default Kindle Key after 1.5 seconds
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.9: wine py.exe -3 is not python3
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.9: wine python3.exe is not python3
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.9: wine python.exe is not python3
wine: failed to open "C:\\Python27\\python.exe": c0000135
DeDRM v10.0.9: wine C:\Python27\python.exe does not exist
DeDRM v10.0.9: Unable to find python3 executable in WINEPREFIX=""
DeDRM v10.0.9: Ultimately failed to decrypt after 2.5 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Running file type plugin DeDRM failed with traceback:
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 950, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 204, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 68, in processBook
    self.decrypt_voucher(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 112, in decrypt_voucher
    raise Exception("Failed to decrypt KFX DRM voucher with any key")
Exception: Failed to decrypt KFX DRM voucher with any key

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre/customize/ui.py", line 175, in _run_filetype_plugins
  File "calibre_plugins.dedrm.__init__", line 1052, in run
    decrypted_ebook = self.KindleMobiDecrypt(path_to_ebook)
  File "calibre_plugins.dedrm.__init__", line 1003, in KindleMobiDecrypt
    raise DeDRMError("{0} v{1}: Ultimately failed to decrypt after {2:.1f} seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md".format(PLUGIN_NAME, PLUGIN_VERSION,time.time()-self.starttime))
calibre_plugins.dedrm.DeDRMError: DeDRM v10.0.9: Ultimately failed to decrypt after 2.5 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Package KFX (from KFX Input) 2.30.0: Packaging /tmp/calibre_5.44.0_tmp_rzljagg1/0kc7n144.kfx-zip
Processing container: CR!K48MDNYMXX4E503G4K6BJT9Q6V30.kfx
Processing container: CR!R5BQ0FE8495QQBNG824X9GW91ZCQ.kfx
Processing container: Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx
Running file type plugin Package KFX (from KFX Input) failed with traceback:
Traceback (most recent call last):
  File "calibre/customize/ui.py", line 175, in _run_filetype_plugins
  File "calibre_plugins.kfx_input.package_filetype", line 23, in run
    return self.package_kfx(path_to_ebook)
  File "calibre_plugins.kfx_input.package_filetype", line 34, in package_kfx
    kfx_data = YJ_Book(path_to_ebook).convert_to_single_kfx()
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 79, in convert_to_single_kfx
    self.decode_book()
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 213, in decode_book
    container = self.get_container(datafile)
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 331, in get_container
    raise KFXDRMError("Book container %s has DRM and cannot be converted" % datafile.name)
calibre_plugins.kfx_input.kfxlib.utilities.KFXDRMError: Book container Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx has DRM and cannot be converted
KFX metadata reader (from KFX Input) activated for /tmp/calibre_5.44.0_tmp_rzljagg1/hl4v_71x_add_books/0/Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx-zip

I installed 10.0.19 but still no luck, though the logs now look different:

Gather KFX-ZIP (from KFX Input) 2.30.0: Importing /media/alex/Kindle/documents/Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx
Gather KFX-ZIP (from KFX Input): Gathered 5 file(s) as /tmp/calibre_5.44.0_tmp_j2mmqlwm/st95p1bu.kfx-zip
DeDRM v10.0.19: Trying to decrypt st95p1bu.kfx-zip
Decrypting KFX-ZIP ebook: st95p1bu
Found 1 keys to try after 1.0 seconds
Decrypting KFX DRM voucher: voucher
Envelope version com.amazon.drm.VoucherEnvelope@10014.0
Got 0 shared key candidates {} amzn1.drm-voucher.v1.7d1a23db-7866-4bc8-8e1e-a9e872df344f
Lock parameters used: ['CLIENT_ID']
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Failed all decryption attempts and no key candidate available
Traceback (most recent call last):
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 112, in decrypt_voucher
    voucher.decryptvoucher()
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1422, in decryptvoucher
    raise lastexception
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1406, in decryptvoucher
    b = pkcs7unpad(b, 16)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 788, in pkcs7unpad
    _assert(paddinglen > 0 and paddinglen <= blocklen, "Incorrect padding - Wrong key")
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 126, in _assert
    raise Exception(msg)
Exception: Incorrect padding - Wrong key
Envelope version com.amazon.drm.VoucherEnvelope@10014.0
Got 0 shared key candidates {} amzn1.drm-voucher.v1.7d1a23db-7866-4bc8-8e1e-a9e872df344f
Lock parameters used: ['CLIENT_ID']
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Decryption failed, trying next fallback 
Failed all decryption attempts and no key candidate available
Traceback (most recent call last):
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 112, in decrypt_voucher
    voucher.decryptvoucher()
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1422, in decryptvoucher
    raise lastexception
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1406, in decryptvoucher
    b = pkcs7unpad(b, 16)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 788, in pkcs7unpad
    _assert(paddinglen > 0 and paddinglen <= blocklen, "Incorrect padding - Wrong key")
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 126, in _assert
    raise Exception(msg)
Exception: Incorrect padding - Wrong key
Failed to decrypt KFX DRM voucher with any key... Hoping that keylist has a book key. 
Decrypting KFX DRMION: Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx
DeDRM v10.0.19: Failed to decrypt with error: Incorrect AES key length (0 bytes)
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 950, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime,dedrmprefs["kindleextrakeyfile"], dedrmprefs["remove_watermarks"])
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 204, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 75, in processBook
    DrmIon(BytesIO(data[8:-8]), lambda name: self.voucher,self.skeylist).parse(outfile)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1618, in parse
    self.processpage(ct, civ, outpages, decompress, decrypt)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1647, in processpage
    aes = AES.new(self.key[:16], AES.MODE_CBC, civ[:16])
  File "Crypto/Cipher/AES.py", line 232, in new
  File "Crypto/Cipher/__init__.py", line 79, in _create_cipher
  File "Crypto/Cipher/_mode_cbc.py", line 274, in _create_cbc_cipher
  File "Crypto/Cipher/AES.py", line 93, in _create_base_cipher
ValueError: Incorrect AES key length (0 bytes)
DeDRM v10.0.19: Looking for new default Kindle Key after 1.0 seconds
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.19: wine py.exe -3 is not python3
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.19: wine python3.exe is not python3
Application could not be started, or no application associated with the specified file.
ShellExecuteEx failed: File not found.

DeDRM v10.0.19: wine python.exe is not python3
wine: failed to open "C:\\Python27\\python.exe": c0000135
DeDRM v10.0.19: wine C:\Python27\python.exe does not exist
DeDRM v10.0.19: Unable to find python3 executable in WINEPREFIX=""
DeDRM v10.0.19: Ultimately failed to decrypt after 2.0 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Running file type plugin DeDRM failed with traceback:
Traceback (most recent call last):
  File "calibre_plugins.dedrm.__init__", line 950, in KindleMobiDecrypt
    book = k4mobidedrm.GetDecryptedBook(path_to_ebook,kindleDatabases,androidFiles,serials,pids,self.starttime,dedrmprefs["kindleextrakeyfile"], dedrmprefs["remove_watermarks"])
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/k4mobidedrm.py", line 204, in GetDecryptedBook
    mb.processBook(totalpids)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/kfxdedrm.py", line 75, in processBook
    DrmIon(BytesIO(data[8:-8]), lambda name: self.voucher,self.skeylist).parse(outfile)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1618, in parse
    self.processpage(ct, civ, outpages, decompress, decrypt)
  File "/home/alex/.config/calibre/plugins/DeDRM.zip/ion.py", line 1647, in processpage
    aes = AES.new(self.key[:16], AES.MODE_CBC, civ[:16])
  File "Crypto/Cipher/AES.py", line 232, in new
  File "Crypto/Cipher/__init__.py", line 79, in _create_cipher
  File "Crypto/Cipher/_mode_cbc.py", line 274, in _create_cbc_cipher
  File "Crypto/Cipher/AES.py", line 93, in _create_base_cipher
ValueError: Incorrect AES key length (0 bytes)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "calibre/customize/ui.py", line 175, in _run_filetype_plugins
  File "calibre_plugins.dedrm.__init__", line 1052, in run
    decrypted_ebook = self.KindleMobiDecrypt(path_to_ebook)
  File "calibre_plugins.dedrm.__init__", line 1003, in KindleMobiDecrypt
    raise DeDRMError("{0} v{1}: Ultimately failed to decrypt after {2:.1f} seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md".format(PLUGIN_NAME, PLUGIN_VERSION,time.time()-self.starttime))
calibre_plugins.dedrm.DeDRMError: DeDRM v10.0.19: Ultimately failed to decrypt after 2.0 seconds. Read the FAQs at noDRM's repository: https://github.com/noDRM/DeDRM_tools/blob/master/FAQs.md
Package KFX (from KFX Input) 2.30.0: Packaging /tmp/calibre_5.44.0_tmp_j2mmqlwm/st95p1bu.kfx-zip
Processing container: CR!K48MDNYMXX4E503G4K6BJT9Q6V30.kfx
Processing container: CR!R5BQ0FE8495QQBNG824X9GW91ZCQ.kfx
Processing container: Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx
Running file type plugin Package KFX (from KFX Input) failed with traceback:
Traceback (most recent call last):
  File "calibre/customize/ui.py", line 175, in _run_filetype_plugins
  File "calibre_plugins.kfx_input.package_filetype", line 23, in run
    return self.package_kfx(path_to_ebook)
  File "calibre_plugins.kfx_input.package_filetype", line 34, in package_kfx
    kfx_data = YJ_Book(path_to_ebook).convert_to_single_kfx()
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 79, in convert_to_single_kfx
    self.decode_book()
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 213, in decode_book
    container = self.get_container(datafile)
  File "calibre_plugins.kfx_input.kfxlib.yj_book", line 331, in get_container
    raise KFXDRMError("Book container %s has DRM and cannot be converted" % datafile.name)
calibre_plugins.kfx_input.kfxlib.utilities.KFXDRMError: Book container Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx has DRM and cannot be converted
KFX metadata reader (from KFX Input) activated for /tmp/calibre_5.44.0_tmp_j2mmqlwm/3uxtw5ys_add_books/0/Frieren_ Beyond Journey's End -Prelude-, Vol. 1 (novel)_B0FR4M6859.kfx-zip

Wine errors should be ignored from my understanding, plugin was trying to reach K4PC, which is not installed. Any ideas what's wrong? Any chance to get it working again, without resorting to K4PC?

[ElleKayEm]

They have update the DRM on that firmware. My Oasis 2 is in the same boat.

[fliker09]

I've read around that 5.18+ was the problematic firmware... How come 5.16 is now a pain too?

[ElleKayEm]

Apparently Amazon sends a software patch which allows a change to the KFX DRM. So far of the Kindles that have stopped receiving updates this is the only firmware this has happened to. But others may follow.

[Satsuoni]

They have seemingly repurposed diagnostics mechanism to load arbitrary amazon-provided library from internet and inject it into book loading process, which allows them to add, well, anything they want without "updating firmware".

[fliker09]

How devious of them... Oh well, time to take my money elsewhere! I will try to extract my recent purchases using K4PC and if need be will ask for your help. Thanks for the answers!