how can use chmod() in assembly debian x86 ?

[G3n3Rall]

hello friends, i wanna use chmod() in linux x86 [debian 3.7.2 x86] but i have some problem in function argv

look at this function:

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 int chmod(const char *path, mode_t mode);

and mode_t modes:

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       S_ISUID  (04000)  set-user-ID  (set  process  effective  user   ID   on
                         execve(2))

       S_ISGID  (02000)  set-group-ID  (set  process  effective  group  ID  on
                         execve(2);  mandatory  locking,   as   described   in
                         fcntl(2);  take a new file's group from parent direcق
                         tory, as described in chown(2) and mkdir(2))

       S_ISVTX  (01000)  sticky bit (restricted deletion flag, as described in
                         unlink(2))

       S_IRUSR  (00400)  read by owner

       S_IWUSR  (00200)  write by owner

       S_IXUSR  (00100)  execute/search  by owner ("search" applies for direcق
                         tories, and means that entries within  the  directory
                         can be accessed)

       S_IRGRP  (00040)  read by group

       S_IWGRP  (00020)  write by group

       S_IXGRP  (00010)  execute/search by group

       S_IROTH  (00004)  read by others

       S_IWOTH  (00002)  write by others

       S_IXOTH  (00001)  execute/search by others

i want to add write permission to my file but it not work !
this code first print hello then change file permission and then exit
print and exit are success but not change file permission
i asked in many forums but no one didn't help ,
code:

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section .text
        global  _start
_start:
        mov     eax,15
        mov     ebx,path
        mov     ecx,mod
        int     0x80
        mov     edx,len
        mov     ecx,msg
        mov     ebx,1
        mov     eax,4
        int     0x80
        mov     ebx,0
        mov     eax,1
        int     0x80
section .data
        msg db          "Hello",0xa
        len equ         $ - msg
        path db           "/root/Desktop/xpl/1.txt"
        mod db       "S_IWUSR|S_IWGRP|S_IWOTH"

i know there is some problem in ecx and mode_t value
anyone can tell me how i do it ? thanks

[saulgoode]

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        mod db       "S_IWUSR|S_IWGRP|S_IWOTH"

Here you are defining mod as a string (i.e., a pointer to a memory location). You want to define mod as a value. I'm not sure of the exact syntax you should use, but something along the lines of:

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mod equ S_IWUSR|S_IWGRP|S_IWOTH

[G3n3Rall]

thanks for answer
i did solve this with [ 777 permission ]

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root@g3n3rall:~# gdb --quiet --batch -ex 'print /x 00777 | 01'
$1 = 0x1ff

so

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mov ecx,0x1ff

and also this can use:

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mov    ecx,00777Q