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hardening-check - check binaries for security hardening features
hardening-check [options] [ELF ...
Examine a given set of ELF binaries and check for several security hardening
features, failing if they are not all found.
This utility checks a given list of ELF
binaries for several security
hardening features that can be compiled into an executable. These
- Position Independent Executable
This indicates that the executable was built in such a way (PIE) that
the ``text'' section of the program can be relocated in memory. To take
full advantage of this feature, the executing kernel must support text
Address Space Layout Randomization (ASLR).
- Stack Protected
This indicates that there is evidence that the ELF was compiled with the
gcc(1) option -fstack-protector (e.g. uses __stack_chk_fail). The
program will be resistant to having its stack overflowed.
When an executable was built without any character arrays being allocated
on the stack, this check will lead to false alarms (since there is no
use of __stack_chk_fail), even though it was compiled with the correct
- Fortify Source functions
This indicates that the executable was compiled with
-D_FORTIFY_SOURCE=2 and -O1 or higher. This causes certain unsafe
glibc functions with their safer counterparts (e.g. strncpy instead
of strcpy), or replaces calls that are verifiable at runtime with the
runtime-check version (e.g. __memcpy_chk insteade of memcpy).
When an executable was built such that the fortified versions of the glibc
functions are not useful (e.g. use is verified as safe at compile time, or
use cannot be verified at runtime), this check will lead to false alarms.
In an effort to mitigate this, the check will pass if any fortified function
is found, and will fail if only unfortified functions are found. Uncheckable
conditions also pass (e.g. no functions that could be fortified are found, or
not linked against glibc).
- Read-only relocations
This indicates that the executable was build with -Wl,-z,relro to
have ELF markings (RELRO) that ask the runtime linker to mark any
regions of the relocation table as ``read-only'' if they were resolved
before execution begins. This reduces the possible areas of memory in
a program that can be used by an attacker that performs a successful
memory corruption exploit.
- Immediate binding
This indicates that the executable was built with -Wl,-z,now to have
ELF markings (BIND_NOW) that ask the runtime linker to resolve all
relocations before starting program execution. When combined with RELRO
above, this further reduces the regions of memory available to memory
- --nopie, -p
No not require that the checked binaries be built as PIE.
- --nostackprotector, -s
No not require that the checked binaries be built with the stack protector.
- --nofortify, -f
No not require that the checked binaries be built with Fority Source.
- --norelro, -r
No not require that the checked binaries be built with RELRO.
- --nobindnow, -b
No not require that the checked binaries be built with BIND_NOW.
- --quiet, -q
Only report failures.
- --verbose, -v
Report verbosely on failures.
- --report-functions, -R
After the report, display all external functions needed by the ELF.
- --find-libc-functions, -F
Instead of the regular report, locate the libc for the first ELF on the
command line and report all the known ``fortified'' functions exported by
- --color, -c
Enable colorized status output.
- --lintian, -l
Switch reporting to lintian-check-parsable output.
Report some debugging during processing.
- --help, -h, -?
Print a brief help message and exit.
- --man, -H
Print the manual page and exit.
When all checked binaries have all checkable hardening features detected,
this program will finish with an exit code of 0. If any check fails, the
exit code with be 1. Individual checks can be disabled via command line
Kees Cook <firstname.lastname@example.org
COPYRIGHT AND LICENSE
Copyright 2009-2013 Kees Cook <email@example.com
This program is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; version 2 or later.
- RETURN VALUE
- COPYRIGHT AND LICENSE
- SEE ALSO