fasdump : program to dump contents of fas files

Index > Linux > fasdump : program to dump contents of fas files

Goto page Previous 1, 2

Author

Thread

Tarkin

Joined: 27 Aug 2010
Posts: 22

Tarkin 04 Sep 2010, 06:43

...the file? I can't seem to find it... Embarassed

TIA,
Tarkin

04 Sep 2010, 06:43

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20519
Location: In your JS exploiting you and your system

revolution 04 Sep 2010, 06:53

Make sure you are logged in and then see the first post in this thread.

04 Sep 2010, 06:53

DJ Mauretto

Joined: 14 Mar 2007
Posts: 464
Location: Rome,Italy

DJ Mauretto 04 Sep 2010, 07:31

Hello, while testing your program I got an error
'File is corrupt, signature is invalid'
in your source code you define hdr.signature 1B736166 but
fas use 1A736166, i changed in 1A736166 and now it's OK..

Code:

  if (hdr.signature != 0x1B736166)  {
            fprintf(stderr, "File is corrupt, signature is invalid\n");
              goto out_error;
     }

Fasm signature is

Code:

                                flat assembler
                       Symbolic information file format


   Table 1  Header
  /-- -----------------------------------------------------------------------\
  | Offset | Size    | Description                                         |
  |========|=========|======================================================|
  |   +0   |  dword  | Signature 1A736166h (little-endian).               |
  |--------|---------|------------------------------------------------------|

_________________
Nil Volentibus Arduum Razz

04 Sep 2010, 07:31

Tarkin

Joined: 27 Aug 2010
Posts: 22

Tarkin 04 Sep 2010, 07:38

Doh! I have to remember to login...

Have a suggestion:

Code:

#define FASMSIGNATURE 0xDEADBEEF /* Change 0xDEADBEEF to the current fasm signature */
...
/*if (hdr.signature != 0x1B736166)  {*/
  if (hdr.signature != FASMSIGNATURE)  {

For fasm 1.69.18, the signature is 0x1A736166

Thanks for fasdump! I will try and work on a shell script which will filter fasdump's output and
prints out fixed-up addresses ( for Linux ELF 32 ).

TTFN,
Tarkin

04 Sep 2010, 07:38

Tomasz Grysztar

Joined: 16 Jun 2003
Posts: 8367
Location: Kraków, Poland

Tomasz Grysztar 04 Sep 2010, 08:21

Tarkin wrote:

For fasm 1.69.18, the signature is 0x1A736166

Note: http://board.flatassembler.net/topic.php?p=92185#92185
It was this way for fasm 1.68 already.

04 Sep 2010, 08:21

Tarkin

Joined: 27 Aug 2010
Posts: 22

Tarkin 04 Sep 2010, 08:40

Ah, yes, missed that post. But I was intending it as fix for fasdump, as DJ Mauretto pointed out.

Also, here is the awk one-liner I hinted at earlier:

Code:

fasdump -s prog.fas | awk '/(\.text)|(\.rodata)|(\.bss)/ { OFFSET=0x08048074; ADDR = strtonum($4) + OFFSET ; printf("%s : 0x%08X\n",$1,ADDR)  } '

Thanks all and HTH,
Tarkin

04 Sep 2010, 08:40

mariosk8s

Joined: 29 Oct 2015
Posts: 1
Location: Hüfingen, Germany

mariosk8s 29 Oct 2015, 09:54

I experienced segfaults on linux due to 2s compliment issues when casting (uint32_t)(*token_ptr).
Something like 89 00 00 00 turned into 89 ff ff ff resulting in rather long lengths.
The attached patch makes these char types unsigned (uint8_t).
I also adjusted the hdr.signature to 1B.

I added the .txt extension because of "The Extension patch is not allowed" error when posting.

Description:	patch to make char uint8_t	Download
Filename:	fasdump.patch.txt
Filesize:	3.78 KB
Downloaded:	2085 Time(s)

_________________
Regards

Mario

29 Oct 2015, 09:54

Goto page Previous 1, 2

< Last Thread | Next Thread >

Forum Rules:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum