How to add code to binary file?

gulfstream · 08-20-2009, 08:45 AM

Hello,

How can I add programming code to existing binary program, is it possible? Like Inno setup installer is additional code over the package inside and when I run the setup.exe (produced by inno) it is not started the program inside, but the additional code over it and then the files are installed/extracted.

I just search for some way to run code before the main linux console binary file (or at the end of this file), but with scripting will be visible to others the programming code.

Like:

script.sh:
#!/bin/bash
./my_code.exe
./standard_linux_code.exe (linux binary)

Can I do it with zip library. What is the easy way?

Thank you.

Gulfstream

rizhun · 08-20-2009, 09:32 AM

Can't be done.

Imagine the security implications of being able to inject 'extra' code into previously compiled binaries! Scary.

I'm guessing you're up to no good, why would you be concerned if the end-user could see you were running one program before another?

Sergei Steshenko · 08-20-2009, 09:39 AM

Quote:

Originally Posted by gulfstream

Hello,

How can I add programming code to existing binary program, is it possible? Like Inno setup installer is additional code over the package inside and when I run the setup.exe (produced by inno) it is not started the program inside, but the additional code over it and then the files are installed/extracted.

I just search for some way to run code before the main linux console binary file (or at the end of this file), but with scripting will be visible to others the programming code.

Like:

script.sh:
#!/bin/bash
./my_code.exe
./standard_linux_code.exe (linux binary)

Can I do it with zip library. What is the easy way?

Thank you.

Gulfstream

It may be possible in some cases. Start from here: http://en.wikipedia.org/wiki/Dynamic_linker#LD_PRELOAD .

rizhun · 08-20-2009, 09:57 AM

Safe.
:O

theNbomr · 08-20-2009, 10:39 AM

If you have the ability to modify file locations (ie root privileges), then you can create a simple compiled and linked binary which can load and run the original runtime binary.

Code:

#include <stdio.h>
#include <stdlib.h>

int childPid;

int main(int argc, char * argv[] ){

    childPid = fork();
    if( childPid ){    /* I am the parent... */
        /* do something or wait for child */
    }
    else{              /* I am the child...  */

        /* Maybe do some processing here; depends on your requirments...
        */
        execvp( "/the/original/program", argv );

        /* We never return from exec...   */
    }
}

Once this is compiled and linked, you still have to arrange that it gets run by default, instead of the original code. That requires moving/renaming files, hence the requirement to be root.

--- rod.

gnashley · 08-20-2009, 12:10 PM

PDV -payload delivery vehicle, can be used to create a binary ELF self-extracting archive which extracts a payload from itself when run and can execute a script at the same time.

orgcandman · 08-20-2009, 12:54 PM

Quote:

Originally Posted by rizhun

Can't be done.

Imagine the security implications of being able to inject 'extra' code into previously compiled binaries! Scary.

I'm guessing you're up to no good, why would you be concerned if the end-user could see you were running one program before another?

Actually, that's how many programs work. Look up Dyninst, or as one responded wrote - LD_PRELOAD. Some unix flavors don't support LD_PRELOAD, or have that functionality disabled for security reasons.

Afa the original question goes, there are many ways of doing what you require. Some would have you simply put a marker at end of the file, write your binary into the file, and then search out the marker for extraction. Many of the SUN / nVidia .bin files work by having a script with the tar embedded (and you can probably have some encryption/password for protection). As one user noted, PDV is a way of accomplishing a 'self-extracting' file.

crabboy · 08-20-2009, 01:30 PM

gulfstream: what are you trying to accomplish by appending another binary to an existing one. It probably can be done if you're compiling the binary yourself, but otherwise you'd have to append the binary and find a way to jump to the new instructions in this new appendage, not at all easy.

If you goal is to create an installer, it can be accomplished with a shell script. I've done it many times before and it's fairly simple, there are examples all over the internet.

gulfstream · 08-20-2009, 02:03 PM

Hello,

I just want to add binary to binary code (no src available) and I thought that I can do it somehow - to make new binary, like copy-paste of text to text via cat:-) it's like a small program preparing some things before to run other binary. I like the easy simple way like theNbomr wrote in his code. I already had similar idea. With editor can be traced the command that will be started in shellexec/shell, this will be no problem at all.

Thank you for helping me with your ideas!

Gulfstream

crabboy · 08-20-2009, 02:19 PM

Yes, It can be done if you are compiling your own program.