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.
dmesgfs is another example file system, which displays the device tree
information gained from dmesg(8) as a directory hierarchy. The information
can be displayed in files, or as targets of symbolic links.
% l /mnt/mainbus0
total 320
drwxr-xr-x 2 agc agc 512 May 21 22:21 .
drwxr-xr-x 2 root wheel 0 Jan 1 1970 ..
drwxr-xr-x 2 agc agc 512 May 21 22:21 acpi0
lrwxr-xr-x 1 agc agc 41 May 21 22:21 cpu0 -> cpu0 at mainbus0 apid 0: (boot processor)
lrwxr-xr-x 1 agc agc 40 May 21 22:21 ioapic -> ioapic at mainbus0 apid 1 not configured
drwxr-xr-x 2 agc agc 512 May 21 22:21 pci0
% l /mnt/mainbus0/pci0/piixide0/atabus1/atapibus0
total 256
drwxr-xr-x 2 agc agc 512 May 21 22:21 .
drwxr-xr-x 2 agc agc 512 May 21 22:21 ..
lrwxr-xr-x 1 agc agc 31 May 21 22:21 Description -> atapibus0 at atabus1: 2 targets
lrwxr-xr-x 1 agc agc 104 May 21 22:21 cd0 -> cd0 at atapibus0 drive 0: <VMware Virtual IDE CDROM Drive, 1000000000000000000, 0000000> cdrom removable
%
- remove cpu_exit.9.
- remove ctxsw.9 from makefile because it's too stale.
XXX maybe it will revive as mi_switch.9 later.
- add cpu_switchto.9 to makefile.
Introduce a parameter -r to control the root node type. For example
"dtfs -r 'lnk /etc' /puffs" mounts dtfs with the root node as a
symbolic link to /etc:
jojonaru# ./dtfs -r 'lnk /etc' /puffs
jojonaru# ls -l /puffs
lrw-rw-rw- 1 root wheel 4 May 17 14:06 /puffs -> /etc
jojonaru# cd /puffs
jojonaru# pwd
/etc
jojonaru#
Extra credit for figuring out how to unmount this file system with
umount(8).
Likewise, "dtfs -r 'chr 2 12' /puffs" makes /puffs (i386) /dev/zero etcetc.
Bug fixes:
- Fix crash reported by Scott Ellis on current-users@.
- Fix race conditions in enforcing the Veriexec rename and remove
policies. These are NOT security issues.
- Fix memory leak in rename handling when overwriting a monitored
file.
- Fix table deletion logic.
- Don't prevent query requests if not in learning mode.
KPI updates:
- fileassoc_table_run() now takes a cookie to pass to the callback.
- veriexec_table_add() was removed, it is now done internally. As a
result, there's no longer a need for VERIEXEC_TABLESIZE.
- veriexec_report() was removed, it is now internal.
- Perform sanity checks on the entry type, and enforce default type
in veriexec_file_add() rather than in veriexecctl.
- Add veriexec_flush(), used to delete all Veriexec tables, and
veriexec_dump(), used to fill an array with all Veriexec entries.
New features:
- Add a '-k' flag to veriexecctl, to keep the filenames in the kernel
database. This allows Veriexec to produce slightly more accurate
logs under certain circumstances. In the future, this can be either
replaced by vnode->pathname translation, or combined with it.
- Add a VERIEXEC_DUMP ioctl, to dump the entire Veriexec database.
This can be used to recover a database if the file was lost.
Example usage:
# veriexecctl dump > /etc/signatures
Note that only entries with the filename kept (that is, were loaded
with the '-k' flag) will be dumped.
Idea from Brett Lymn.
- Add a VERIEXEC_FLUSH ioctl, to delete all Veriexec entries. Sample
usage:
# veriexecctl flush
- Add a 'veriexec_flags' rc(8) variable, and make its default have
the '-k' flag. On systems using the default signatures file
(generaetd from running 'veriexecgen' with no arguments), this will
use additional 32kb of kernel memory on average.
- Add a '-e' flag to veriexecctl, to evaluate the fingerprint during
load. This is done automatically for files marked as 'untrusted'.
Misc. stuff:
- The code for veriexecctl was massively simplified as a result of
eliminating the need for VERIEXEC_TABLESIZE, and now uses a single
pass of the signatures file, making the loading somewhat faster.
- Lots of minor fixes found using the (still under development)
Veriexec regression testsuite.
- Some of the messages Veriexec prints were improved.
- Various documentation fixes.
All relevant man-pages were updated to reflect the above changes.
Binary compatibility with existing veriexecctl binaries is maintained.
controllers. These controllers can be found on add-on PCIe cards, or
on some motherboards to provide the PATA connectivity (e.g. some intel
ICH8-based motherboards).
Thanks to JMicron Technology for providing me documentation and
different sample boards for this work.
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