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  #1  
Old 03-22-2013, 03:15
netseeker netseeker is offline
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Question need to help for cracking ELF linux

Hi all,

I am pretty new to linux reversing. I have a target whcih I want to choose between either following techniques :

1- change a constant string
2- change a JNE to JMP

I analysed my target using IDA and found the correct place to patch. but since the ELF file is "stripped" I am not quite sure if I change the JNE to JMP in HEX mode, does it solve my problem?.

the other way is, to change the constant string in HEX mode but the string needs to be the same length or less.

my problem : I want a reliable debugger/disassembler running under linux for doing such task(either changing string without hassale or change OP codes). which tool do you suggest?

Best,
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Old 03-22-2013, 05:29
sendersu sendersu is offline
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Red face

My favorite tool for such a tasks is hiew (a windows tool one)

you don't need a reliable debugger/disassemble to do these kind of things (patching and bytes changeout)

just an old good hex editor with a disassembler inside.
thats it
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  #3  
Old 03-23-2013, 08:16
|roe |roe is offline
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Take a look at these posts, I hope they are useful:
[1] Basic RE under Linux - http://hypervion.blogspot.com/2012/07/basic-reverse-engineering-for-study.html
[2] GDB and DWARF standard under Linux - http://hypervion.blogspot.com/2012/07/using-gdb-and-dwarf-standard-for.html
[3] Debugging under Linux - http://hypervion.blogspot.com/2012/06/asm-and-debugging-on-linux-what-is-deal.html

hexedit tool or Bless Hex Editor (GUI) should do the job to change opcodes.
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Old 03-23-2013, 10:04
QuakeGamer QuakeGamer is offline
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You can simply use Hopper-Disassembler to patch it.
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Old 03-24-2013, 02:32
wilson bibe wilson bibe is offline
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Look this: http://www.winehq.org/, Open Source Software for running Windows; and this: http://www.howtogeek.com/133515/4-ways-to-run-windows-software-on-linux/ applications on other operating systems, maybe this can help you.
Regards
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  #6  
Old 05-08-2013, 07:51
swork3 swork3 is offline
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the best (native, open source tool) is ht-editor hte.sf.net, it is not limited to elf/unix, even runs on win
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