🚀 go-pugleaf

Andy Rosen <arosen@hawk.ulowell.edu> writes:

	Say it does work on your machine, and you put it into login,
	but hide the source so users can't use it.  The cracker can
	then just open a pipe to login and use it that way.

First of all, if you care at all about security, /bin/login will have
lots of hooks for logging failed attempts.  Further, as shipped from
most vendors, /bin/login has 4755 permissions -- set-uid to root and
world-executable.  When login gets exec()ed from getty, it's already
running as root, there's no need to make it set-uid.

I think there was some history leading to the ability to login from
someone else's shell, in which case you'd need to be set-uid to change
the tty permissions and write into utmp, etc., but it seems to me
there's limited utility in doing something like this.

Further, most /bin/login implementations i've seen trash the current
utmp entry when you login from the shell.

This is probably counter-productive.

This also probably belongs in comp.unix.wizards ... follow-ups
are directed there.

/jordan