hardening-check
check binaries for security hardening features
see also :
gcc
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.
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examples
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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
Report verbosely on
failures.
--report-functions
After the report, display all
external functions needed by the ELF .
--find-libc-functions
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
Enable colorized status output.
--lintian
Switch reporting to
lintian-check-parsable output.
--debug
Report some debugging during processing.
--help,
-h, -?
Print a brief help message and
exit.
--man
Print the manual page and exit.
copyright and license
Copyright 2009-2012 Kees Cook <kees[:at:]debian[:dot:]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.
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.
see also
gcc ,
hardening-wrapper
author
Kees Cook
<kees[:at:]debian[:dot:]org>