MIPS executable format?

I can't find what the MIPS R4000 executable format is....I've googled the crap out of that phrase too...

I believe it's ELF, like the Dreamcast uses...but I'm not sure. Does anyone know?

I'm asking because I'm trying to find a MIPS executable to decompile with IDA Standard...for the www.psp-linux.org project...

It seems that when I try to decompile the files in EBOOT.PBP (bootloader type deal on the PSP), I can only view garbage because it's disassembled as Intel metapc....and I'm not given the option for any MIPS procs even though IDA Standard supports MIPS.


A_T

Hi AxessTerminated,

Is this what you're looking for...

http://www.jps.at/pefile.html
IT Solution & Services The Portable Executable File Format

Eg ;)

Not quite...I don't think.

I want to know the format of code compiled for the MIPS R4000 processor.

A_T

I'm not sure what you're looking for so...maybe it's on this page...

http://www.google.ca/search?client=f...=Google+Search
Google Search: code compiled for the MIPS R4000 processor

Okay, a more specific question...is the .ELF extension a MIPS binary file as .EXE extension is a Windows binary file?

A_T

This may well be so out of date as to be useless, but it might give you some ideas :)

From what I remember a MIPS executable is a compiled binary, but I do not think that it is an ELF file, I would have thought COFF (.cff)

MIPS is a RISC system so I would expect executables to be written in assembly then whacked through the MIPS compiler. Maybe you need a disassembler tool as part of your kit?

I also believe that there is a brand of "C" (C- -), that's minus, minus, that is supported IIRC.

Sorry, it has been a very long time :eek:

Hi nihil,

Is this the C you're talking about...

http://64.233.167.104/search?q=cache...ient=firefox-a
MIPSpro C++ Programmer’s Guide

Hi Eg~

I don't think so, I believe that it was "C-minus-minus" which I understand meant "C minus the hard stuff", but that could have been sarcasm :D

I think that Microsoft and Harvard University were involved? (late 1990s.............I think C++ goes back to the eighties?)

I just had another thought about the format "a.out" is a possibility and something like ".flat"

As I recall, these RISC boxes are not that fussy about extensions, they get the format from a "magic number" and stuff in the header.

If Axess could attach a small sample file I might be able to work out what it is?

That's the problem, I don't have any files. I need a MIPS R4000 executable so I can disassemble it and compare it to some other things I have from the PSP.

A_T

Maybe the files are encrypted/obfuscated?

Edit: Forgot compressed...

I can't find any actual binary for it... however, there are several simulators out there and sample code. Why not create your own?

http://www.cs.wisc.edu/~larus/spim.html
http://vip.cs.utsa.edu/classes/cs2734s98/code.html
http://chortle.ccsu.edu/AssemblyTuto...lContents.html

well I use SPIM...and i wrote a simple program...but I can't compile it from Windows. There are a few cross-assemblers for Linux, but I'm not to linux-oriented or w/e.

A_T

Hmmmm,

Quote:

---

It seems that when I try to decompile the files in EBOOT.PBP (bootloader type deal on the PSP), I can only view garbage because it's disassembled as Intel metapc....and I'm not given the option for any MIPS procs even though IDA Standard supports MIPS.

---

But you say that you don't have a MIPS R4000 executable file?..................I think that you have gotten hold of an "emulator" file...............these were part of modules to let you emulate MIPS/RISC on other platforms..............OK for learning, but not for analysis/development. In that case I am not surprised that you saw a load of nonsense, and it doesn't matter what format, it is not what we need?

I think that you need to get us an example, otherwise we will get nowhere?

cheers

Yea there partly (by the look of things) encrypted with 128bit AES encryption, I wanna get my hands on one and experiment with a side channel crypto attack, but im a poor student so have no pennys to waste on an expensive toy at the moment.

Its weird the psp-linux people dont seem to have pushed so hard as the ds-linux people did with there hardware, i dont get why they havent tried changing or disconnected the clock speed to see whether the AES keys are generated from the RT clock. they keep saying theyll be ready in a month, and there researching but just seems like there pussy footing around.

i2c

Well the admin at psp-linux.org is the same guy who runs dslinux, so I think the deadline is possible. There have been alot of talks about trying a buffer overflow or even getting unencrypted data from memory to do some work with.

A_T

[QUOTE] from a PM to i2c
This is the EBOOT.PBP unpacker: http://pdc.me.uk/pbp/pbp-unpacker-050.exe

The 13MB PBP can be found here: http://dj01.psp.update.playstation....e4b24/EBOOT.PBP

After that, I just disassembled as x86 code and was checking out the plaintext. the PBP contains a few files, and I wanted to find out what was what.
[QUOTE]

Hi

Recently, I was made to pay attention to this page, which describes quite
nicely executable file formats[1], partly very detailed (credits to white_scorpion).
Really good read.

as per your MIPS problem (if it still is one :) )
Can't you compile it using as[2], with the -mips3 option? Then, you would
have a binary to use. See details for MIPS ELF[3] and MIPS ECOFF[4]

Cheers.


[1] http://www.nondot.org/sabre/os/artic...leFileFormats/
[2] http://www.nondot.org/~sabre/Project...UAssembler.pdf
[3] http://www.tachyonsoft.com/elf.pdf
[4] http://turing.une.edu.au/~comp283/cd.../sde-guide.pdf

p.s. I am aware that this thread is a few days old. The link to [1] I just got
a few days ago.