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.
We only enable 8-bit output for known single-byte locales, currently
ISO8859-*. For all other locales the program output is unchanged.
RFC-1288 recommends that administrators have a mechanism to enable
characters greater than ASCII 126. A suggested solution is an
environment variable. The environment variables of choice here are
LC_CTYPE and LANG.
Thanks to Martin Husemann <martin@duskware.de> for the idea on checking
for known single-byte locales, to Johan Danielsson <joda@pdc.kth.se> for
checking RFC-1288, and to Jun-ichiro itojun Hagino <itojun@iijlab.net>
for insisting on retaining security for multi-byte locales.
If you experience any problems with these changes, please send me email
describing the problem and how to repeat it. I'd rather try to fix the
problem than have this change reverted. Thanks!
daemon is a bad idea, (2) there's no standard in 8bit finger, (3) there's no
guarantee that finger/fingerd uses the same locale, (4) existing finger client
could scream. see tech-userlevel.
valid for output. If something bad gets printed, either the locale
settings for the user (or output terminal) are wrong, or the LC_CTYPE
definitions on the system are invalid.
valid for output. If something bad gets printed, either the locale
settings for the user (or output terminal) are wrong, or the LC_CTYPE
definitions on the system are invalid.
kim