ELF/DWARF Parser to Out Structure elements - debugging

Is there a way to extract the size and address of elements within a structure using an elf file? I am hoping there is a tool available that can do this and export it to a more readable format.
My end goal is to convert the ELF file to a ASAM A2L file. A open source/free tool that could do this would even be better but most companies that do this charge alot for their tools.

I don't know offhand of anything pre-canned, but it isn't very hard to modify an existing tool to do it.
The "pahole" program from the "dwarves" project does something similar. It prints a structure definition in a certain way.
There's also a "pahole.py" script for gdb that does pretty much the same thing. This would be trivial to modify to print things however you like.
If you want to get a little deeper you could write it yourself using one of the existing DWARF libraries. I like the one in elfutils, but YMMV.

Related

Extracting strings for translation from VB6 code

I have a legacy VB application that still has some life in it, and I am wanting to translate it to another language.
I plan to write a Ruby script, possibly utilising a parser, to extract all strings from the three million lines of source, replace them with constants, and move them to a string resource file that can be used to provide translations.
Is anyone aware of a script/library that could be used to intelligently extract the strings?
I'm not aware of any existing off-the-shelf tool that you could use. We created a tool like this at my work and it worked well. The FRM file format is quite simple (although only briefly documented). We wrote a tool that (1) extracted all strings from control definitions and (2) generated the code to reload them at runtime during Form_Load.

How can one create a polyglot PDF?

I like reading the PoC||GTFO issues and one thing I found remarkable when I first discovered it, was the "polyglot" nature of their PDF files.
Let met explain: when you consider for example their 8th issue, you may unzip files from it; execute the encryption they are talking about by running it as a script and even better(worse?) with their 9th issue you can even play it as a music file!
I'm currently in the process of writing small scripts every week and writing each time a little one page PDF in LaTeX to explain the said scripts. So I would really enjoy being able to create the same kind of PDF files. Sadly they explained (partly) in their first issue how to include zip files, but they did so through three small sketches of cmd lines without actual explanations.
So my question is basically :
how can one create such a polyglot PDF file containing stuff like a zip as well as being a shell script which may be run using arguments just like normal scripts?
I'm asking here about the process of creation, not just an explanation of how this is possible. The ideal way for me would that there are already some scripts or programs allowing to create easily such PDF files.
I've tried to search the net for the keywords "polyglot files" and others of the kind and wasn't able to find any useful matches. Maybe this process has another name?
I've already read the presentation by Julia Wolf which explains how things works, but I sadly haven't had time to apply the knowledge there to real world, because I'm sadly not used to play with file headers and the way a PDF is constructed.
EDIT:
Okay, I've read more and found the 7th edition of PoC||GTFO to be really informative concerning this subject. I may end up being able to create my own scripts to do such polyglot PDF files if I have some more time to consider it.
I played around with polyglots myself after attending Ange's talks and also talking to him in person. You really need to understand the file formats to be able to nest them into each other.
However, long story short, here are some links I found extremely useful for creating polyglots:
Some older Google Code Trunk
PoC of the polyglot stuff
Especially the second link (to github) will help you creating polyglots, but also understanding how they are working and how they are implemented. Since it is mostly Python stuff and very well / clean written, it is very useful and easy to follow.
I feel dissecting some file formats would be a good place to start. You can find many file format specifications for different file types through Google, but they can be a tough read and will likely take you some time to translate into whatever language you are using.
PDF: https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf
ELF: https://www.cs.cmu.edu/afs/cs/academic/class/15213-s00/doc/elf.pdf
ZIP: http://kat.sdf.org/zip_file_format.txt
The language(s) you select will need a way to read and write raw bytes (not just ascii alphanumeric), so perhaps C would be good for more direct access to memory. Some Python tricks could help with open sourcing the scripts easily.
To dissect the files, you may want to build a tool kinda like https://github.com/kvesel/zipbrk/ to take them apart, then put them all back together in a polyglot format. For example, zip does not require the section headers to be at the start (or even contiguous for that matter), and PDF magic number can appear in multiple places within the file as well. I also believe I recall a polyglot tool being included in one of the PoC||GTFO publishings (maybe issue 8 or 2??) as a polyglot in the pdf file.
Don't forget the hackers bible! :)
https://nostarch.com/gtfo

Getting data from .dat files

I'm hoping somebody out there can help me with this. I'm attempting to extract some barcode data from some .dat files. Its a B Tree file system with groups of three files .dat .ix. .dia. The company that wrote the software (a long time ago) say that the program is written in Pascal. I have no experience in reverse engineering but from what I read its most likely the only way to extract the data as the structure of the database is contained in the code of the program. I'm looking for advice on where to start.
I suppose the first thing you need to do is to see if the exe you've got was written with Delphi. You can check with this: http://cc.embarcadero.com/Item/15250
Then, to see if the exe that creates those .dat files were made with 'TurboPower B-Tree Filer', the I'd suggest you download and take a look at this: http://sourceforge.net/projects/tpbtreefiler/
At this step, looking at these sources is needed to familiarize yourself with the class names used in 'TurboPower B-Tree Filer' to help determine if any of those classes were used in your exe.
Then, using 'XN Resource Editor' [search the Internet for this] or, probhably better, 'MiTeC Portable Executable Reader' [ http://www.mitec.cz/pe.html ], see if any class names are relevant.
If they are, then you're in luck --sort of. All you will need to do is to write an app using 'TurboPower B-Tree Filer' to import the data in your dat files to export or manipulate as you wish.
At that point, you might find this link useful.
TurboPower B-Tree Filer and Delphi XE2 - Anyone done it?
If, OTOH, none of the above applies; I fear the only option is to reverse engineer the exe you have.

Assigning my own file path in reverse engineering

I am working on reverse engineering and i wanted to give my own file path without using open dialog box like writing a fixed file path and read a file from that every time the software start.i tried to give the file name in a .data section of the software but it retrieve only the hex number not the string.
Is there any way hooking windows API for file open?or any way to write in memory and to read it every time the software starts?Any advice or direction would be greatly appreciated.
I think that what you may be looking for is "intercepting system call", quick google search came up with this link:
http://jbremer.org/intercepting-system-calls-on-x86_64-windows/ so it should be possible and not too difficult.
Basically if you manage to intercept a call to GetOpenFileName and replace it with custom implementation you should be able to do what you want (that is put hardcoded file path to appropriate buffer in LPOPENFILENAME structure)
As for your attempt to modify compiled code (I assume that what you are referring as reverse engineering is disassembling and modifying binaries) it should be possible to do, but it will require deep knowledge of windows binary architecture and assembly language.

Are there alternatives to ibtool for parsing NIB files?

As part of an i18n project, I need to extract strings from a NIB file programmatically. This can be done quite easily with ibtool, of course. But this is a cross-platform product, of which the NIB is only part. It would be nice if we didn't have to lock string extraction to a particular machine, or have to kludge together catalog-merge scripts.
So I realize it's a long shot, since the demand for this is probably quite low, but are there any open-source alternatives to ibtool? Is there any documentation on the NIB format reliable enough to write a parser from?
If you use XIBs, then they are simple XML files. Just look for string elements that have the key NSContents. If you're familiar with XML parsing, it shouldn't take long to reverse engineer --export-strings-file in almost any language.
If you can't move to XIBs, you can read the keyedobjects.nib, which is a binary plist. One portable reader is the Perl implementation plutil.pl. You can also look at Apple's open source code to handle them in CFBinaryPlist.c. If you need to go this way, look at OpenCFLite. Reading and writing Plists is a key reason people use the portable Core Foundation.

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