On Thu, 23 Nov 2006 16:05:13 +0200
"Eng. Mina Ramses" <[EMAIL PROTECTED]> wrote:

> Correctly i want to know  how not Null-terminated to be implemented in
> a code ,
>  Null characters, causes most buffer overflow vulnerabilities to not
>  be
> triggered correctly, because the function stops copying when a Null
> byte is encountered. , is that right ?
>  i don't mean by a code the source i mean the idea ,
> Also how/what is to bind a shell to a high port ?

1. please bottom post.

http://home.nyc.rr.com/computertaijutsu/linfaq.html#netiquette

2. null characters are what STOP the copying of data in string
functions. some string functions will copy until they reach a NULL
character. other functions have a user defined limit, such as strncpy,
which will copy until a NULL character is reached OR the user defined
limit is reached. in which case, strncpy does not NULL-terminate if the
character limit is reached. this can be a problem if the user does not
know of this, or simply neglects this fact.

character strings in c can be very confusing from other languages that
add some sugar to the way that computers handle memory, such as in perl,
where one can simply say "my $v = 'abc';" and the interpreter creates
the variable, with adequate memory, and expands/contacts that allocation
as required.

in c land we have realloc to do this, and all the possible outcomes
and fun therein.

3. shells are not bound to ports. sockets are bound to ports. please
look in the manual pages to see how to assign a port to your
socket-based shell.

-- 
Regards, Ed                      :: http://www.openbsdhacker.com
proud python hacker
The Dead Sea Scroll is locked up in the Vatican's vault for fear that 
people will find out that it was Chuck Norris who divide the Red Sea 
and not Moses. 

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