SunOS and shared libraries, security aspects

[BURNS,JIM]

in article <4006 at auspex.auspex.com>, guy at auspex.auspex.com (Guy Harris) says:

>>Rather, it's to make login non-setuid in the first place. The only time
>>login should run as root is from a controlled daemon, such as telnetd or
>>getty.

> I've no problem with that

Excuse me, but I don't understand how login (su, rsh, rlogin) would be
able to change your uid without using setuid(3) which is documented as
needing superuser status:

NAME
     setuid, seteuid, setruid, setgid, setegid, setrgid - set
     user and group ID
[...]
     These calls are only permitted to the super-user or if the
     argument is the real or effective ID.
-- 
BURNS,JIM
Georgia Institute of Technology, Box 30178, Atlanta Georgia, 30332
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