This is a very "raw" version of my CRC32 compensation/collision library/tools. You can use tweakcrc with a file, an offset and a target CRC and it'll patch the file at <offset> so that it has <crc> as a CRC.
I am sorry for the lack of documentation, I retrieved this in some temporary directory and had completely forgotten to release it. I figured I would better put a raw version out, at least for archiving purposes than forget about it again.
This might be the worse piece of code you have ever seen, sorry. It was written in a rush a long time ago with the intent to never re-use it and was then resurected many years later.
The method I developed is explained here (in french).
-- Julien TINNES
$ dd if=/dev/urandom of=toto bs=1024 count=1024 $ ./tweakcrc -f toto -c 0xDEADBEEF -o 0x100 TweakCRC (C) Julien TINNES