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View Full Version : Hex Editor - Tivo Hacking



klimon
05-22-2007, 12:13 PM
Are there any Hex Editors that run on Tivo or do I have to copy a target file to a PC and do Hex Editing under Windows, Linux or Mac?

ScanMan
05-22-2007, 10:46 PM
Here (http://www.dealdatabase.com/forum/showthread.php?t=42540&highlight=hexedit) is a hex editor for the tivo; others use simple echo/dd commands to patch tivoapp. WARNING: know what you are doing, especially the difference between "file offsets" and virtual memory addresses (VMA). Failure to heed could be hazardous to your tivo. It's probably more prudent to patch on the PC where you can verify original values before overwriting them.

Narf54321
05-23-2007, 10:23 AM
If you have a series-2 (or series-3) and AlphaWolf's All-in-One Utilities (tivotools) you can do rudimentary hex checking via the hexdump command.

This example shows the current values: (From System software v4.0.1b only).


echo 'Check for Enable Backdoors | Disabled=0260 2821, Enabled=2405 0001'
dd if=tivoapp bs=1 skip=5401464 count=4 2>/dev/null | hexdump -v

Note that the address 5401464 is the decimal value for 0x526B78 (hex). Since this is from the v4.0.1b of tivoapp, obviously the values are going to change with other Tivo software revisions.

To change the values, copy the running tivoapp file to /var or someplace, make sure the drive partition is read-write and you can do something like this:


echo -ne "\x24\x05\x00\x01" | dd conv=notrunc of=tivoapp bs=1 seek=5401464


Again, the exact values are going to be different depending upon the software version running on your tivo.