FORTIFY_SOURCE feature of libssp, thus checking the size of arguments to
various string and memory copy and set functions (as well as a few system
calls and other miscellany) where known at function entry. RedHat has
evidently built all "core system packages" with this option for some time.
This option should be used at the top of Makefiles (or Makefile.inc where
this is used for subdirectories) but after any setting of LIB.
This is only useful for userland code, and cannot be used in libc or in
any code which includes the libc internals, because it overrides certain
libc functions with macros. Some effort has been made to make USE_FORT=yes
work correctly for a full-system build by having the bsd.sys.mk logic
disable the feature where it should not be used (libc, libssp iteself,
the kernel) but no attempt has been made to build the entire system with
USE_FORT and doing so will doubtless expose numerous bugs and misfeatures.
Adjust the system build so that all programs and libraries that are setuid,
directly handle network data (including serial comm data), perform
authentication, or appear likely to have (or have a history of having)
data-driven bugs (e.g. file(1)) are built with USE_FORT=yes by default,
with the exception of libc, which cannot use USE_FORT and thus uses
only USE_SSP by default. Tested on i386 with no ill results; USE_FORT=no
per-directory or in a system build will disable if desired.
1. Immediately ignore all the signals we want to ignore and set the alarm.
2. Before we exit on error, restore all signals we modified
3. Before we exec a shell, restore all signals we modified and ignore TSTP.
Job control aware shells know how to deal with this.
4. Temporarily handle SIGINT while we read motd.
with MKPIC=no, possibly because the target does not support shared
libraries, these include libraries required to resolve all symbols
which end up referenced from PAM-using applications. The libraries
presently required are -lcrypt, -lrpcsvc and -lutil.
Add use of these variables which are currently set up to use PAM,
so that they compile when MKPIC=no.
Also, in the telnetd case, reorder the order of the libraries, so
that libtelnet.a comes before -ltermcap and -lutil, again to fix
link error when MKPIC=no.
Discussed with thorpej and christos.
addition to the host name. This option is needed by programs suchs as
telnetd, because at the point they invoke login, they already have opened
a pty, and the stdin of login is no longer the socket connected to the
remote host. In addition don't chop the hostname up to the first dot if
the domain matches. These practices are 70's fashion and they only serve
to lose information. These days we have long enough fields in utmpx and
wtmpx to store the full names.
lukem