You need to understand the following:

• All * .dmg files are encrypted.
  
• To unpack * .dmg files - neededkeys.
  
• Keysnot available for all versions of iOS and not for each device.
  
• All keys are available on the site ->Firmware keys

To extract the files we need:

• 7-zip ->archiver for unpacking * .ipsw
  
• iDecryptIt ->program for working with * .dmg
  
• Firmware keys ->keys for unpacking * .dmg

For example, take the firmware from iPhone 5 (iOS 9.3.3) ->iPhone5,1_9.3.3_13G34_Restore.ipsw
Unpacking ->iPhone5,1_9.3.3_13G34_Restore.ipswvia7-zip



Open the folder ->iPhone5,1_9.3.3_13G34_Restore and see the following:

• Firmware - the firmware of third-party chips in the iOS device.
  
• 058-48920-034.dmg - update image.
  
• 058-49042-034.dmg - the image of the file system (the largest size), in the future it will interest us.
  
• 058-49199-034.dmg - recovery image.
  
• BuildManifest.plist is a file with information for iTunes.
  
• kernelcache.release.n41 is the core of iOS.
  
• Restore.plist - contains device information for recovery mode.

Run ->iDecryptIt
Click onSelect Input File and choose 058-49042-034.dmg


Specify the key in the fieldKey from the website Firmware keys
Root filesystem ->f3383acd6f0c441cef2a6c03dadd4d9887d72f0bf2fd010a349ab445f781f9d466abc5bc

PushDecrypt , the file system image is decrypted and saved next to the source file.


Next we need to unpack058-49042-034_decrypted.dmg
Click onSelect Input File and choose 058-49042-034_decrypted.dmg


PushExtract for unpacking 058-49042-034_decrypted.dmg
If after pressingExtract nothing happens (there is no process in the command line), copy 2 files from 7-Zip (7z.exe, 7z.dll) and replace the files in iDecryptIt.


After automatically performing all the necessary actions in the command window, a new folder will appear in the iPhone5,1_9.3.3_13G34_Restore folderGenoa13G34.N41OS (This is the code name of the firmware, depending on the version of iOS it may change).



It should be borne in mind that unpacking the firmware in the above way, not all files will be in the form in which they are presented on the device itself. All files with the * .plist extension will be empty, due to the fact that they are “filled” during the installation of iOS.

Post has been editedT0ugh - 05.07.17, 17:02