Support and General Use > Theming and Appearance Customization

Customize the original Iriver IHP-120/140 firmware

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ATAGA:
I need ihpbmp, it´s in the web ROCKBOX:

http://www.rockbox.org/wiki/IriverToolsGuide#ihpfirm_40firmware_encryption_47decryption_tool_41

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A short description of the decryption

DaveHooper : The code is divided into 512-byte blocks. We initialise a 16-byte mask with a fixed pattern and XOR this with the first 16 bytes of the block. Then we write out the bytes in the following order: 2,3,4,1,6,7,8,5,10,11,12,9,14,15,16,13. Then we shift these bytes into the mask and use it to XOR the next 16 bytes. At the end of the 512-byte block, we reinitialise the 16-byte XOR mask with the fixed pattern. At the end of the firmware image is the checksum block. For each 512-byte block we derive one checksum (this checksum is actually just the XOR of all decoded bytes).

Are we sure that the firmware is 100% correctly decrypted? I'm pretty certain - certainly the decryption, edit, reencryption steps work and the resulting modified firmware runs on the device. Proof at ihpbmp (graphics/icons modification tool for iHP). If someone has some time to kill they could analyse the decryption routine in the firmware and compare with my source if they liked.

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OK?

saratoga:
You could ask strip wax if he still has it since apparently he wrote it.

AlexP:
Please, ask the person who wrote it.  This isn't a Rockbox tool and we don't have anything to do with it.  The links are that the person that wrote it is/was a Rockbox developer and some parts of the code were incorporated into a Rockbox tool.

Also, in future if you feel I (or anyone else) has wrongly locked a thread, PM me - don't just start a new one.

ATAGA:
Excuse me, I thought this program was part of the decryption tools for editing the original firmware. I'm afraid I will not be able to get it.

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