Interactive Rsync Authentication Problem

jw schultz jw at
Thu May 29 10:33:51 EST 2003

On Wed, May 28, 2003 at 04:14:54PM -0400, Carson Gaspar wrote:
> --On Wednesday, May 28, 2003 13:26:17 -0400 Andrew Klein 
> <andy at> wrote:
> >I believe J.W. Schultz replied to this but I lost it since I was not yet
> >fully subscribed to the list. He rightly suggested that the a portable
> >getpass() would be non-trivial.  An alternate suggestion though:  Solaris
> >has a getpassphrase() call that returns up to 256 chars.  The configure
> >script could check if the function exists and do an appropriate #define.
> >Then authenticate.c can be made a bit be smarter in a generally portable
> >way.
> getpassphrase() is definitely worth using. OpenSSH also has a portable 
> readpassphrase() that you could steal.

But how portable is readpassphrase really?  And how much
would we have to change in autoconf to use it?  If
getpassphrase is much like getpass then i'd say we could use
it.  But i don't want to see any "#ifdef SOLARIS", autoconf
would have to set HAVE_GETPASSPHRASE or something like that.

> I love the fact that the man page for getpass() under Linux says "don't use 
> this", but does not provide any alternative. Mmmm... Linux - it's so 
> secure! ;-)

Try SUSv2:

	 The return value points to static data whose content may be
	 overwritten by each call. 

	 This function was marked LEGACY since it provides no
	 functionality which a user could not easily implement, and
	 its name is misleading. 



SUSv3 doesn't even define getpass.

Somewhere along the way the committees decided that since
getpass was so "simple" it wasn't needed in the libs.
Strncpy is even easier to implement and a bad design (no
terminate on truncate) should it be dropped too?  I'll agree
that getpass's design is poor but that means it should get a
better replacement, not be dropped.

In reality i don't expect getpass to be dropped for some
time.  There are too many utilities using it that would
suddenly be broken were it dropped.  It is easier for the
vendors to add it back in than to field the support calls
when software won't build.

	J.W. Schultz            Pegasystems Technologies
	email address:		jw at

		Remember Cernan and Schmitt

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