Subject: Re: Using objdump from x86 to disassemble MIPS binaries
To: None <netbsd-users@netbsd.org>
From: Gilbert Fernandes <gilbert.fernandes@spamcop.net>
List: netbsd-users
Date: 12/18/2005 19:07:33
> Not sure, but you want to pass -O xxx and -D xxx to build.sh to
> ensure the build doesn't poo all over the source tree.

It's not a problem. I will reinstall source sets if
required.

It works fine.

I have built the tools for MIPS big-endian by using

./build.sh -m evbmips-eb tools

This dropped an objdump with support for MIPS binaries in :

/usr/src/tooldir.NetBSD-2.1-i386/bin

And then it's just using the command on the MIPS binaries
to get the assembly dump :

./sh--netbsdelf-objdump -d -EB -m sh binary

The -EB flag is probably not required in fact.

I'm trying to dump the code for the binary which is used
to build the image uploaded as firmware. So I'll be able
to edit the firmware at will (it uses squashfs) and uploaded
properly checksum-ed binaries there :)

The hardest part is going to find the loop and routine
in the MIPS code so I can reverse engineer it and
reprogram it using C. But since I already got images
and checksums it should not be long to find (I hope it's
a CRC16 or CRC32 - I got to try that first).

Thanks for the help.

--
unzip ; strip ; touch ; grep ; finger ; mount ; fsck ; more ; yes ;
fsck ; umount ; sleep