3 # Build log hardening check, checks build logs for missing hardening flags.
5 # Copyright (C) 2012 Simon Ruderich
7 # This program is free software: you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation, either version 3 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
25 use Term::ANSIColor ();
26 use Text::ParseWords ();
28 our $VERSION = '0.01';
33 # Regex to catch compiler commands.
35 (?<!\.)(?:cc|gcc|g\+\+|c\+\+)
38 # Full regex which matches the complete compiler name. Used in a few places to
39 # prevent false negatives.
40 my $cc_regex_full = qr/
41 (?:[a-z0-9_]+-(?:linux-|kfreebsd-)?gnu(?:eabi|eabihf)?-)?
44 # Regex to catch (GCC) compiler warnings.
45 my $warning_regex = qr/^(.+?):([0-9]+):[0-9]+: warning: (.+?) \[(.+?)\]$/;
47 # List of source file extensions which require preprocessing.
48 my @source_preprocess_compile_cpp = (
50 qw( cc cp cxx cpp CPP c++ C ),
54 my @source_preprocess_compile = (
60 @source_preprocess_compile_cpp,
62 qw( F FOR fpp FPP FTN F90 F95 F03 F08 ),
64 my @source_preprocess_no_compile = (
68 my @source_preprocess = (
69 @source_preprocess_compile,
70 @source_preprocess_no_compile,
72 # List of source file extensions which don't require preprocessing.
73 my @source_no_preprocess_compile_cpp = (
79 my @source_no_preprocess_compile = (
83 @source_no_preprocess_compile_cpp,
87 qw( f for ftn f90 f95 f03 f08 ),
89 my @source_no_preprocess_no_compile = (
93 my @source_no_preprocess = (
94 @source_no_preprocess_compile,
95 @source_no_preprocess_no_compile,
97 # List of header file extensions which require preprocessing.
98 my @header_preprocess = (
99 # C, C++, Objective-C, Objective-C++
102 qw( hh H hp hxx hpp HPP h++ tcc ),
105 # Hashes for fast extensions lookup to check if a file falls in one of these
107 my %extensions_no_preprocess = map { $_ => 1 } (
108 @source_no_preprocess,
110 my %extensions_preprocess = map { $_ => 1 } (
114 my %extensions_compile_link = map { $_ => 1 } (
116 @source_no_preprocess,
118 my %extensions_compile = map { $_ => 1 } (
119 @source_preprocess_compile,
120 @source_no_preprocess_compile,
122 my %extensions_no_compile = map { $_ => 1 } (
123 @source_preprocess_no_compile,
124 @source_no_preprocess_no_compile,
126 my %extensions_compile_cpp = map { $_ => 1 } (
127 @source_preprocess_compile_cpp,
128 @source_no_preprocess_compile_cpp,
130 my %extension = map { $_ => 1 } (
131 @source_no_preprocess,
132 @source_no_preprocess_compile,
133 @source_no_preprocess_compile_cpp,
134 @source_no_preprocess_no_compile,
137 @source_preprocess_compile,
138 @source_preprocess_compile_cpp,
139 @source_preprocess_no_compile,
142 # Regexp to match file extensions.
143 my $file_extension_regex = qr/
145 \S+ # Filename without extension.
147 ([^\\.\s]+) # File extension.
148 (?=\s|\\) # At end of word. Can't use \b because some files have non
149 # word characters at the end and because \b matches double
150 # extensions (like .cpp.o). Works always as all lines are
151 # terminated with "\n".
154 # Expected (hardening) flags. All flags are used as regexps.
159 my @def_cflags_format = (
162 '-Werror=format-security',
164 my @def_cflags_fortify = (
165 # fortify needs at least -O1, but -O2 is recommended anyway
167 my @def_cflags_stack = (
169 '--param=ssp-buffer-size=4',
171 my @def_cflags_pie = (
177 # @def_cxxflags_* is the same as @def_cflags_*.
178 my @def_cppflags = ();
179 my @def_cppflags_fortify = (
180 '-D_FORTIFY_SOURCE=2',
182 my @def_ldflags = ();
183 my @def_ldflags_relro = (
186 my @def_ldflags_bindnow = (
189 my @def_ldflags_pie = (
193 my @def_ldflags_pic = (
197 # Renaming rules for the output so the regex parts are not visible. Also
198 # stores string values of flag regexps above, see compile_flag_regexp().
200 '-O(?:2|3)' => '-O2',
201 '-Wl,(-z,)?relro' => '-Wl,-z,relro',
202 '-Wl,(-z,)?now' => '-Wl,-z,now',
205 # Statistics of missing flags and non-verbose build commands. Used for
209 preprocess_missing => 0,
211 compile_missing => 0,
213 compile_cpp_missing => 0,
217 commands_nonverbose => 0,
220 # Use colored (ANSI) output?
227 my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_;
229 # Get string value of qr//-escaped regexps and if requested rename them.
230 my @missing_flags = map {
231 $flag_renames_ref->{$_}
232 } @{$missing_flags_ref};
234 my $flags = join ' ', @missing_flags;
235 printf "%s (%s)%s %s",
236 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
239 sub error_non_verbose_build {
243 error_color('NONVERBOSE BUILD', 'red'),
244 error_color(':', 'yellow'),
247 sub error_hardening_wrapper {
249 error_color('HARDENING WRAPPER', 'red'),
250 error_color(':', 'yellow'),
251 'no checks possible, aborting';
254 my ($message, $color) = @_;
257 return Term::ANSIColor::colored($message, $color);
264 my ($line, @flags) = @_;
266 foreach my $flag (@flags) {
267 return 1 if $line =~ /$flag/;
273 my ($line, $missing_flags_ref, @flags) = @_;
275 my @missing_flags = ();
276 foreach my $flag (@flags) {
277 if (not $line =~ /$flag/) {
278 push @missing_flags, $flag;
282 return 1 if scalar @missing_flags == 0;
284 @{$missing_flags_ref} = @missing_flags;
288 # Modifies $missing_flags_ref array.
289 sub pic_pie_conflict {
290 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
292 return 0 if not $pie;
293 return 0 if not any_flags_used($line, @def_ldflags_pic);
295 my %flags = map { $_ => 1 } @flags_pie;
297 # Remove all PIE flags from @missing_flags as they are not required with
300 not exists $flags{$_}
301 } @{$missing_flags_ref};
302 @{$missing_flags_ref} = @result;
304 # We got a conflict when no flags are left, thus only PIE flags were
305 # missing. If other flags were missing abort because the conflict is not
307 return scalar @result == 0;
310 sub is_non_verbose_build {
311 my ($line, $next_line, $skip_ref) = @_;
313 if (not ($line =~ /^checking if you want to see long compiling messages\.\.\. no/
314 or $line =~ /^\s*\[?(?:CC|CCLD|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
315 or $line =~ /^\s*(?:C|c)ompiling\s+(.+?)(?:\.\.\.)?$/
316 or $line =~ /^\s*(?:B|b)uilding (?:program|shared library)\s+(.+?)$/
317 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
323 # On the first pass we only check if this line is verbose or not.
324 return 1 if not defined $next_line;
326 # Second pass, we have access to the next line.
329 # CMake and other build systems print the non-verbose messages also when
330 # building verbose. If a compiler and the file name occurs in the next
331 # line, treat it as verbose build.
333 # Get filename, we can't use the complete path as only parts of it are
334 # used in the real compiler command.
335 $file =~ m{/([^/\s]+)$};
338 if ($next_line =~ /\Q$file\E/ and $next_line =~ /$cc_regex/o) {
339 # We still have to skip the current line as it doesn't contain any
349 sub compile_flag_regexp {
350 my ($flag_renames_ref, @flags) = @_;
353 foreach my $flag (@flags) {
354 # Store flag name in replacement string for correct flags in messages
355 # with qr//ed flag regexps.
356 $flag_renames_ref->{qr/\s$flag(?:\s|\\)/}
357 = (exists $flag_renames_ref->{$flag})
358 ? $flag_renames_ref->{$flag}
361 # Compile flag regexp for faster execution.
362 push @result, qr/\s$flag(?:\s|\\)/;
367 sub extension_found {
368 my ($extensions_ref, @extensions) = @_;
371 foreach my $extension (@extensions) {
372 if (exists $extensions_ref->{$extension}) {
383 # Parse command line arguments.
385 my $option_version = 0;
387 my $option_bindnow = 0;
389 my $option_arch = undef;
390 my $option_buildd = 0;
392 if (not Getopt::Long::GetOptions(
393 'help|h|?' => \$option_help,
394 'version' => \$option_version,
396 'pie' => \$option_pie,
397 'bindnow' => \$option_bindnow,
398 'all' => \$option_all,
400 'color' => \$option_color,
401 'arch=s' => \$option_arch,
402 'buildd' => \$option_buildd,
405 Pod::Usage::pod2usage(2);
409 Pod::Usage::pod2usage(1);
411 if ($option_version) {
412 print "blhc $VERSION Copyright (C) 2012 Simon Ruderich
414 This program is free software: you can redistribute it and/or modify
415 it under the terms of the GNU General Public License as published by
416 the Free Software Foundation, either version 3 of the License, or
417 (at your option) any later version.
419 This program is distributed in the hope that it will be useful,
420 but WITHOUT ANY WARRANTY; without even the implied warranty of
421 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
422 GNU General Public License for more details.
424 You should have received a copy of the GNU General Public License
425 along with this program. If not, see <http://www.gnu.org/licenses/>.
435 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
437 @def_cflags = compile_flag_regexp(\%flag_renames, @def_cflags);
438 @def_cflags_format = compile_flag_regexp(\%flag_renames, @def_cflags_format);
439 @def_cflags_fortify = compile_flag_regexp(\%flag_renames, @def_cflags_fortify);
440 @def_cflags_stack = compile_flag_regexp(\%flag_renames, @def_cflags_stack);
441 @def_cflags_pie = compile_flag_regexp(\%flag_renames, @def_cflags_pie);
442 @def_cxxflags = compile_flag_regexp(\%flag_renames, @def_cxxflags);
443 @def_cppflags = compile_flag_regexp(\%flag_renames, @def_cppflags);
444 @def_cppflags_fortify = compile_flag_regexp(\%flag_renames, @def_cppflags_fortify);
445 @def_ldflags = compile_flag_regexp(\%flag_renames, @def_ldflags);
446 @def_ldflags_relro = compile_flag_regexp(\%flag_renames, @def_ldflags_relro);
447 @def_ldflags_bindnow = compile_flag_regexp(\%flag_renames, @def_ldflags_bindnow);
448 @def_ldflags_pie = compile_flag_regexp(\%flag_renames, @def_ldflags_pie);
449 @def_ldflags_pic = compile_flag_regexp(\%flag_renames, @def_ldflags_pic);
454 FILE: foreach my $file (@ARGV) {
455 open my $fh, '<', $file or die "$!: $file";
457 # Hardening options. Not all architectures support all hardening options.
458 my $harden_format = 1;
459 my $harden_fortify = 1;
460 my $harden_stack = 1;
461 my $harden_relro = 1;
462 my $harden_bindnow = $option_bindnow; # defaults to 0
463 my $harden_pie = $option_pie; # defaults to 0
465 while (my $line = <$fh>) {
466 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
467 # check for hardening flags in buildd mode if an older dpkg-dev is
468 # used. Default flags (-g -O2) are still checked.
470 # Packages which were built before 1.16.1 but used their own hardening
471 # flags are not checked.
472 if ($option_buildd and $line =~ /^Toolchain package versions: /) {
473 require Dpkg::Version;
474 if ($line !~ /dpkg-dev_(\S+)/
475 or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
485 # If hardening wrapper is used (wraps calls to gcc and adds hardening
486 # flags automatically) we can't perform any checks, abort.
487 if ($line =~ /^Build-Depends: .*\bhardening-wrapper\b/) {
488 if (not $option_buildd) {
489 error_hardening_wrapper();
491 print "I-hardening-wrapper-used\n";
497 # We skip over unimportant lines at the beginning of the log to
498 # prevent false positives.
499 last if $line =~ /^dpkg-buildpackage:/;
502 # Input lines, contain only the lines with compiler commands.
505 my $continuation = 0;
506 my $complete_line = undef;
507 while (my $line = <$fh>) {
508 # And stop at the end of the build log. Package details (reported by
509 # the buildd logs) are not important for us. This also prevents false
511 last if $line =~ /^Build finished at \d{8}-\d{4}$/;
513 # Detect architecture automatically unless overridden.
515 and $line =~ /^dpkg-buildpackage: host architecture (.+)$/) {
519 # Ignore compiler warnings for now.
520 next if $line =~ /$warning_regex/o;
522 if ($line =~ /\033/) { # esc
523 # Remove all ANSI color sequences which are sometimes used in
524 # non-verbose builds.
525 $line = Term::ANSIColor::colorstrip($line);
526 # Also strip '\0xf' (delete previous character), used by Elinks'
529 # And "ESC(B" which seems to be used on armhf and hurd (not sure
531 $line =~ s/\033\(B//g;
534 # Check if this line indicates a non verbose build.
535 my $non_verbose = is_non_verbose_build($line);
537 # One line may contain multiple commands (";"). Treat each one as
538 # single line. parse_line() is slow, only use it when necessary.
539 my @line = (not $line =~ /;/)
542 # Ensure newline at the line end - necessary for
543 # correct parsing later.
546 } Text::ParseWords::parse_line(';', 1, $line);
547 foreach $line (@line) {
551 # Join lines, but leave the "\" in place so it's clear where
552 # the original line break was.
553 chomp $complete_line;
554 $complete_line .= ' ' . $line;
556 # Line continuation, line ends with "\".
557 if ($line =~ /\\\s*$/) {
559 # Start line continuation.
560 if (not defined $complete_line) {
561 $complete_line = $line;
566 if (not $continuation) {
567 # Use the complete line if a line continuation occurred.
568 if (defined $complete_line) {
569 $line = $complete_line;
570 $complete_line = undef;
573 # Ignore lines with no compiler commands.
574 next if $line !~ /\b$cc_regex(?:\s|\\)/o and not $non_verbose;
576 # Ignore false positives.
578 # `./configure` output.
579 next if not $non_verbose
580 and $line =~ /^(?:checking|(?:C|c)onfigure:) /;
581 next if $line =~ /^\s*(?:Host\s+)?(?:C\s+)?
582 (?:C|c)ompiler[\s.]*:?\s+
584 (?:\s-std=[a-z0-9:+]+)?\s*$
586 or $line =~ /^\s*(?:- )?(?:HOST_)?(?:CC|CXX)\s*=\s*$cc_regex_full\s*$/o
587 or $line =~ /^\s*-- Check for working (?:C|CXX) compiler: /
588 or $line =~ /^\s*(?:echo )?Using [A-Z_]+\s*=\s*/;
590 next if $line =~ /^Making [a-z]+ in \S+/; # e.g. "[...] in c++"
592 # Check if additional hardening options were used. Used to
593 # ensure they are used for the complete build.
594 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie, @def_ldflags_pie);
595 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
604 if (scalar @input == 0) {
605 print "No compiler commands!\n";
610 if ($option_buildd) {
611 $statistics{commands} += scalar @input;
614 # Option or auto detected.
616 # The following was partially copied from dpkg-dev 1.16.1.2
617 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
618 # copyright Raphaël Hertzog <hertzog@debian.org>, Kees Cook
619 # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
620 # later. Keep it in sync.
623 my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($option_arch);
625 # Disable unsupported hardening options.
626 if ($cpu =~ /^(ia64|alpha|mips|mipsel|hppa)$/ or $option_arch eq 'arm') {
629 if ($cpu =~ /^(ia64|hppa|avr32)$/) {
636 my @cflags = @def_cflags;
637 my @cxxflags = @def_cxxflags;
638 my @cppflags = @def_cppflags;
639 my @ldflags = @def_ldflags;
640 # Check the specified hardening options, same order as dpkg-buildflags.
642 @cflags = (@cflags, @def_cflags_pie);
643 @cxxflags = (@cxxflags, @def_cflags_pie);
644 @ldflags = (@ldflags, @def_ldflags_pie);
647 @cflags = (@cflags, @def_cflags_stack);
648 @cxxflags = (@cxxflags, @def_cflags_stack);
650 if ($harden_fortify) {
651 @cflags = (@cflags, @def_cflags_fortify);
652 @cxxflags = (@cxxflags, @def_cflags_fortify);
653 @cppflags = (@cppflags, @def_cppflags_fortify);
655 if ($harden_format) {
656 @cflags = (@cflags, @def_cflags_format);
657 @cxxflags = (@cxxflags, @def_cflags_format);
660 @ldflags = (@ldflags, @def_ldflags_relro);
662 if ($harden_bindnow) {
663 @ldflags = (@ldflags, @def_ldflags_bindnow);
666 for (my $i = 0; $i < scalar @input; $i++) {
667 my $line = $input[$i];
670 if (is_non_verbose_build($line, $input[$i + 1], \$skip)) {
671 if (not $option_buildd) {
672 error_non_verbose_build($line);
674 $statistics{commands_nonverbose}++;
679 # Even if it's a verbose build, we might have to skip this line.
682 # Remove everything until and including the compiler command. Makes
683 # checks easier and faster.
684 $line =~ s/^.*?$cc_regex//o;
685 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
686 # the brace and similar characters.
687 $line =~ s/['")]+$//;
689 # Skip unnecessary tests when only preprocessing.
690 my $flag_preprocess = 0;
696 # Preprocess, compile, assemble.
697 if ($line =~ /\s(-E|-S|-c)\b/) {
699 $flag_preprocess = 1 if $1 eq '-E';
700 $compile = 1 if $1 eq '-S' or $1 eq '-c';
701 # Otherwise assume we are linking.
706 # Get all file extensions on this line.
707 my @extensions = $line =~ /$file_extension_regex/go;
708 # Ignore all unknown extensions to speedup the search below.
709 @extensions = grep { exists $extension{$_} } @extensions;
711 # These file types don't require preprocessing.
712 if (extension_found(\%extensions_no_preprocess, @extensions)) {
715 # These file types require preprocessing.
716 if (extension_found(\%extensions_preprocess, @extensions)) {
720 # If there are source files then it's compiling/linking in one step
721 # and we must check both. We only check for source files here, because
722 # header files cause too many false positives.
723 if (not $flag_preprocess
724 and extension_found(\%extensions_compile_link, @extensions)) {
725 # Assembly files don't need CFLAGS.
726 if (not extension_found(\%extensions_compile, @extensions)
727 and extension_found(\%extensions_no_compile, @extensions)) {
735 # Assume CXXFLAGS are required when a C++ file is specified in the
739 and extension_found(\%extensions_compile_cpp, @extensions)) {
744 if ($option_buildd) {
745 $statistics{preprocess}++ if $preprocess;
746 $statistics{compile}++ if $compile;
747 $statistics{compile_cpp}++ if $compile_cpp;
748 $statistics{link}++ if $link;
751 # Check hardening flags.
753 if ($compile and not all_flags_used($line, \@missing, @cflags)
754 # Libraries linked with -fPIC don't have to (and can't) be
755 # linked with -fPIE as well. It's no error if only PIE flags
757 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
758 # Assume dpkg-buildflags returns the correct flags.
759 and not $line =~ /`dpkg-buildflags --get CFLAGS`/) {
760 if (not $option_buildd) {
761 error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]);
763 $statistics{compile_missing}++;
766 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
767 # Libraries linked with -fPIC don't have to (and can't) be
768 # linked with -fPIE as well. It's no error if only PIE flags
770 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
771 # Assume dpkg-buildflags returns the correct flags.
772 and not $line =~ /`dpkg-buildflags --get CXXFLAGS`/) {
773 if (not $option_buildd) {
774 error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]);
776 $statistics{compile_cpp_missing}++;
780 if ($preprocess and not all_flags_used($line, \@missing, @cppflags)
781 # Assume dpkg-buildflags returns the correct flags.
782 and not $line =~ /`dpkg-buildflags --get CPPFLAGS`/) {
783 if (not $option_buildd) {
784 error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]);
786 $statistics{preprocess_missing}++;
790 if ($link and not all_flags_used($line, \@missing, @ldflags)
791 # Same here, -fPIC conflicts with -fPIE.
792 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
793 # Assume dpkg-buildflags returns the correct flags.
794 and not $line =~ /`dpkg-buildflags --get LDFLAGS`/) {
795 if (not $option_buildd) {
796 error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]);
798 $statistics{link_missing}++;
805 # Print statistics for buildd mode, only output in this mode.
806 if ($option_buildd) {
809 if ($statistics{preprocess_missing}) {
810 push @warning, sprintf "CPPFLAGS %d (of %d)",
811 $statistics{preprocess_missing},
812 $statistics{preprocess};
814 if ($statistics{compile_missing}) {
815 push @warning, sprintf "CFLAGS %d (of %d)",
816 $statistics{compile_missing},
817 $statistics{compile};
819 if ($statistics{compile_cpp_missing}) {
820 push @warning, sprintf "CXXFLAGS %d (of %d)",
821 $statistics{compile_cpp_missing},
822 $statistics{compile_cpp};
824 if ($statistics{link_missing}) {
825 push @warning, sprintf "LDFLAGS %d (of %d)",
826 $statistics{link_missing},
829 if (scalar @warning) {
830 local $" = ', '; # array join string
831 print "W-dpkg-buildflags-missing @warning missing\n";
834 if ($statistics{commands_nonverbose}) {
835 printf "W-compiler-flags-hidden %d (of %d) hidden\n",
836 $statistics{commands_nonverbose},
837 $statistics{commands},
849 blhc - build log hardening check, checks build logs for missing hardening flags
853 B<blhc> [options] <dpkg-buildpackage build log file>..
857 blhc is a small tool which checks build logs for missing hardening flags and
858 other important warnings. It's licensed under the GPL 3 or later.
866 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
871 Set the specific architecture (e.g. amd64, armel, etc.), automatically
872 disables hardening flags not available on this architecture. Is detected
873 automatically if dpkg-buildpackage is used.
877 Force check for all +bindnow hardening flags. By default it's auto detected.
881 Special mode for buildds when automatically parsing log files. The following
882 changes are in effect:
888 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
895 Use colored (ANSI) output for warning messages.
899 Force check for all +pie hardening flags. By default it's auto detected.
901 =item B<-h -? --help>
903 Print available options.
907 Print version number and license.
911 Auto detection for B<--pie> and B<--bindnow> only works if at least one
912 command uses the required hardening flag (e.g. -fPIE). Then it's required for
913 all other commands as well.
917 The exit status is a "bit mask", each listed status is ORed when the error
918 condition occurs to get the result.
928 No compiler commands were found.
932 Invalid arguments/options given to blhc.
940 Missing hardening flags.
944 Hardening wrapper detected, no tests performed.
950 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
952 =head1 COPYRIGHT AND LICENSE
954 Copyright (C) 2012 by Simon Ruderich
956 This program is free software: you can redistribute it and/or modify
957 it under the terms of the GNU General Public License as published by
958 the Free Software Foundation, either version 3 of the License, or
959 (at your option) any later version.
961 This program is distributed in the hope that it will be useful,
962 but WITHOUT ANY WARRANTY; without even the implied warranty of
963 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
964 GNU General Public License for more details.
966 You should have received a copy of the GNU General Public License
967 along with this program. If not, see <http://www.gnu.org/licenses/>.