[oss] [Assignment 1] [Task 1] no m32 compilation flag

[Alex Teaca]

Hello,

It's not clear for me the task 5 from the GDB section.

1. What means to print the stack ? We have to examine the memory between
the ebp and esp pointers of the current frame stack ?
2. What registers must be printed ? The values of eax, ebx ..., or the
registers saved on stack ?
3. Which is the third frame ? I see that the compute_hash is called from
main. This means that the ebp from the compute_hash frame stack will point
to the ebp from the main frame stack and in this case will be 0.

Thanks, Alex



On Tue, Nov 11, 2014 at 11:42 AM, Lucian Mogosanu <lucian.mogosanu at gmail.com
> wrote:

> On Tue, Nov 11, 2014 at 08:57:02AM +0000, Razvan Nitu wrote:
> > Hello all,
> >
> > When I tried to run the hasher binary I got this error [1]. I
> recompiled, but
> > i received [2]. I figured it might be the fact that I don't have the
> 32-bit
> > library so I compiled everything without the -m32 flag and everything
> worked
> > fine. I think that this might cause some issues if the script contains
> > breakpoints at hardcoded addresses. This leads me to my second question:
> can
> > we assume that ASLR is disabled ?
> >
> > Razvan
> >
> >
> > [1] ./hasher: error while loading shared libraries: libcrypto.so.1.0.0:
> > cannot open shared object file: No such file or directory
> >
> > [2] In file included from /usr/include/openssl/sha.h:63:0,
> >                  from hasher.c:1:
> > /usr/include/openssl/e_os2.h:56:33: fatal error: openssl/opensslconf.h:
> No
> > such file or directory
> >  #include <openssl/opensslconf.h>
>
> The files you are looking for are in the libssl1.0.0 and libssl-dev
> libraries:
>
> spyked at tuvok:~% apt-file search opensslconf.h
> libcyassl-dev: /usr/include/cyassl/openssl/opensslconf.h
> libssl-dev: /usr/include/x86_64-linux-gnu/openssl/opensslconf.h
>
> (obviously you need libssl-dev:i386 if you are going to compile with m32)
>
> spyked at tuvok:~% apt-file search libcrypto.so.1.0.0
> libssl1.0.0: /usr/lib/x86_64-linux-gnu/libcrypto.so.1.0.0
>
> (same here, you need libssl1.0.0:i386)
>
> Lucian
> _______________________________________________
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