Re: Secure temporary fifo creation

[George Georgalis <george@galis.org>]

On Mon, May 17, 2004 at 07:45:17PM -0500, Greg Deitrick wrote:
>Hello,
>
>What is the recommended method for securely creating a temporary named pipe in 
>C code?
>
>Looking at the man pages for various library calls it appears that tmpfile(3) 
>is probably an acceptable means of creating a temporary file, but this 
>returns a FILE *.  The upstram source I'm packaging needs to make a temporary 
>fifo.  It uses tempnam(3) to get a temporary file name as a char *, and then 
>mkfifo(3) to make the fifo named pipe from the file name.  Is this 
>sufficiently secure?


I'm not a c programmer but I think I understand the problem. You could
create a temp directory and a temp file, create the fifo in the temp dir
then move it to the temp file and remove the temp dir -- Which might be
better then the delay between getting the filename and making the fifo.

I assumed a temp dir is as easy to make as a tmp file in c, but I cannot
find how. Is it possible to make a temp file then change its file
descriptor to a fifo?

// George


-- 
George Georgalis, Architect and administrator, Linux services. IXOYE
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