NAME

       hardening-check - check binaries for security hardening features

SYNOPSIS

       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.

DESCRIPTION

       This utility checks a given list of ELF binaries for several security hardening features
       that can be compiled into an executable. These features are:

       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 options.

       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 corruption attacks.

OPTIONS

       --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 libc.

       --color, -c
               Enable colorized status output.

       --lintian, -l
               Switch reporting to lintian-check-parsable output.

       --debug Report some debugging during processing.

       --help, -h, -?
               Print a brief help message and exit.

       --man, -H
               Print the manual page and exit.

RETURN VALUE

       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 options.

AUTHOR

       Kees Cook <kees@debian.org>

COPYRIGHT AND LICENSE

       Copyright 2009-2013 Kees Cook <kees@debian.org>.

       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.

SEE ALSO

       gcc(1), hardening-wrapper(1)