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 Text::ParseWords ();
27 our $VERSION = '0.03';
32 # Regex to catch compiler commands.
34 (?<!\s-) # ignore options, e.g. "-c++" [sic!] (used by swig)
35 (?<!\.) # ignore file names, e.g. "test.gcc"
36 (?:cc|gcc|g\+\+|c\+\+)
37 (?:-[\d.]+)? # version suffix, e.g. "gcc-4.6"
39 # Full regex which matches the complete compiler name. Used in a few places to
40 # prevent false negatives.
41 my $cc_regex_full = qr/
42 (?:[a-z0-9_]+-(?:linux-|kfreebsd-)?gnu(?:eabi|eabihf)?-)?
45 # Regex to check if a line contains a compiler command.
46 my $cc_regex_normal = qr/
49 # Regex to catch (GCC) compiler warnings.
50 my $warning_regex = qr/^(.+?):(\d+):\d+: warning: (.+?) \[(.+?)\]$/;
52 # List of source file extensions which require preprocessing.
53 my @source_preprocess_compile_cpp = (
55 qw( cc cp cxx cpp CPP c++ C ),
59 my @source_preprocess_compile = (
65 @source_preprocess_compile_cpp,
67 qw( F FOR fpp FPP FTN F90 F95 F03 F08 ),
69 my @source_preprocess_no_compile = (
73 my @source_preprocess = (
74 @source_preprocess_compile,
75 @source_preprocess_no_compile,
77 # List of source file extensions which don't require preprocessing.
78 my @source_no_preprocess_compile_cpp = (
84 my @source_no_preprocess_compile_ada = (
87 # If you add another file, fix use of @source_no_preprocess_compile_ada
88 # below (search for $compile_ada).
90 my @source_no_preprocess_compile = (
94 @source_no_preprocess_compile_cpp,
98 qw( f for ftn f90 f95 f03 f08 ),
100 @source_no_preprocess_compile_ada,
102 my @source_no_preprocess_no_compile = (
108 my @source_no_preprocess = (
109 @source_no_preprocess_compile,
110 @source_no_preprocess_no_compile,
112 # List of header file extensions which require preprocessing.
113 my @header_preprocess = (
114 # C, C++, Objective-C, Objective-C++
117 qw( hh H hp hxx hpp HPP h++ tcc ),
121 # Normal object files.
123 # Libtool object files.
125 # Dynamic libraries. bzip2 uses .sho.
131 # Hashes for fast extensions lookup to check if a file falls in one of these
133 my %extensions_no_preprocess = map { $_ => 1 } (
134 # There's no @header_no_preprocess.
135 @source_no_preprocess,
137 my %extensions_preprocess = map { $_ => 1 } (
141 my %extensions_compile_link = map { $_ => 1 } (
143 @source_no_preprocess,
145 my %extensions_compile = map { $_ => 1 } (
146 @source_preprocess_compile,
147 @source_no_preprocess_compile,
149 my %extensions_no_compile = map { $_ => 1 } (
150 @source_preprocess_no_compile,
151 @source_no_preprocess_no_compile,
153 my %extensions_compile_cpp = map { $_ => 1 } (
154 @source_preprocess_compile_cpp,
155 @source_no_preprocess_compile_cpp,
157 my %extensions_object = map { $_ => 1 } (
160 my %extension = map { $_ => 1 } (
161 @source_no_preprocess,
167 # Regexp to match file extensions.
168 my $file_extension_regex = qr/
170 \S+ # Filename without extension.
172 ([^\/\\.,;:\s]+)# File extension.
173 (?=\s|\\) # At end of word. Can't use \b because some files have non
174 # word characters at the end and because \b matches double
175 # extensions (like .cpp.o). Works always as all lines are
176 # terminated with "\n".
179 # Expected (hardening) flags. All flags are used as regexps.
184 my @def_cflags_format = (
186 '-Werror=format-security', # implies -Wformat-security
188 my @def_cflags_fortify = (
189 # fortify needs at least -O1, but -O2 is recommended anyway
191 my @def_cflags_stack = (
193 '--param=ssp-buffer-size=4',
195 my @def_cflags_pie = (
201 # @def_cxxflags_* is the same as @def_cflags_*.
202 my @def_cppflags = ();
203 my @def_cppflags_fortify = (
204 '-D_FORTIFY_SOURCE=2', # must be first, see cppflags_fortify_broken()
205 # If you add another flag fix hack below (search for "Hack to fix").
207 my @def_cppflags_fortify_bad = (
208 # These flags may overwrite -D_FORTIFY_SOURCE=2.
210 '-D_FORTIFY_SOURCE=0',
211 '-D_FORTIFY_SOURCE=1',
213 my @def_ldflags = ();
214 my @def_ldflags_relro = (
217 my @def_ldflags_bindnow = (
220 my @def_ldflags_pie = (
224 my @def_ldflags_pic = (
229 # References to all flags checked by the flag checker.
233 \@def_cflags_fortify,
238 \@def_cppflags_fortify,
241 \@def_ldflags_bindnow,
244 # References to all used flags.
245 my @flag_refs_all = (
247 \@def_cppflags_fortify_bad,
250 # Renaming rules for the output so the regex parts are not visible. Also
251 # stores string values of flag regexps above, see compile_flag_regexp().
253 '-O(?:2|3)' => '-O2',
254 '-Wl,(?:-z,)?relro' => '-Wl,-z,relro',
255 '-Wl,(?:-z,)?now' => '-Wl,-z,now',
259 no_compiler_commands => 1 << 0,
260 # used by POD::Usage => 1 << 1,
261 non_verbose_build => 1 << 2,
262 flags_missing => 1 << 3,
263 hardening_wrapper => 1 << 4,
264 invalid_cmake => 1 << 5,
268 no_compiler_commands => 'I-no-compiler-commands',
269 non_verbose_build => 'W-compiler-flags-hidden',
270 flags_missing => 'W-dpkg-buildflags-missing',
271 hardening_wrapper => 'I-hardening-wrapper-used',
272 invalid_cmake => 'I-invalid-cmake-used',
275 # Statistics of missing flags and non-verbose build commands. Used for
279 preprocess_missing => 0,
281 compile_missing => 0,
283 compile_cpp_missing => 0,
287 commands_nonverbose => 0,
290 # Use colored (ANSI) output?
296 # Only works for single-level arrays with no undef values. Thanks to perlfaq4.
298 my ($first_ref, $second_ref) = @_;
300 return 0 if scalar @{$first_ref} != scalar @{$second_ref};
302 my $length = scalar @{$first_ref};
303 for (my $i = 0; $i < $length; $i++) {
304 return 0 if $first_ref->[$i] ne $second_ref->[$i];
311 my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_;
313 # Get string value of qr//-escaped regexps and if requested rename them.
314 my @missing_flags = map {
315 $flag_renames_ref->{$_}
316 } @{$missing_flags_ref};
318 my $flags = join ' ', @missing_flags;
319 printf '%s (%s)%s %s',
320 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
325 sub error_non_verbose_build {
329 error_color('NONVERBOSE BUILD', 'red'),
330 error_color(':', 'yellow'),
335 sub error_invalid_cmake {
339 error_color('INVALID CMAKE', 'red'),
340 error_color(':', 'yellow'),
345 sub error_hardening_wrapper {
347 error_color('HARDENING WRAPPER', 'red'),
348 error_color(':', 'yellow'),
349 'no checks possible, aborting';
354 my ($message, $color) = @_;
357 return Term::ANSIColor::colored($message, $color);
364 my ($line, @flags) = @_;
366 foreach my $flag (@flags) {
367 return 1 if $line =~ /$flag/;
373 my ($line, $missing_flags_ref, @flags) = @_;
375 my @missing_flags = ();
376 foreach my $flag (@flags) {
377 if (not $line =~ /$flag/) {
378 push @missing_flags, $flag;
382 return 1 if scalar @missing_flags == 0;
384 @{$missing_flags_ref} = @missing_flags;
388 sub cppflags_fortify_broken {
389 my ($line, $missing_flags) = @_;
391 # This doesn't take the position into account, but is a simple solution.
392 # And if the build system tries to force -D_FORTIFY_SOURCE=0/1, something
395 if (any_flags_used($line, @def_cppflags_fortify_bad)) {
396 # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2!
397 push @{$missing_flags}, $def_cppflags_fortify[0];
404 # Modifies $missing_flags_ref array.
405 sub pic_pie_conflict {
406 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
408 return 0 if not $pie;
409 return 0 if not any_flags_used($line, @def_ldflags_pic);
411 my %flags = map { $_ => 1 } @flags_pie;
413 # Remove all PIE flags from @missing_flags as they are not required with
416 not exists $flags{$_}
417 } @{$missing_flags_ref};
418 @{$missing_flags_ref} = @result;
420 # We got a conflict when no flags are left, thus only PIE flags were
421 # missing. If other flags were missing abort because the conflict is not
423 return scalar @result == 0;
426 sub is_non_verbose_build {
427 my ($line, $next_line, $skip_ref) = @_;
429 if (not (index($line, 'checking if you want to see long compiling messages... no') == 0
430 or $line =~ /^\s*\[?(?:CC|CCLD|C\+\+|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
431 or $line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/
432 or $line =~ /^\s*[Bb]uilding (?:program|shared library)\s+(.+?)$/
433 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
439 # C++ compiler setting.
440 return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/;
441 # "Compiling" with no file name.
442 if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) {
443 # $file_extension_regex may need spaces around the filename.
444 return 0 if not " $1 " =~ /$file_extension_regex/o;
449 # On the first pass we only check if this line is verbose or not.
450 return 1 if not defined $next_line;
452 # Second pass, we have access to the next line.
455 # CMake and other build systems print the non-verbose messages also when
456 # building verbose. If a compiler and the file name occurs in the next
457 # line, treat it as verbose build.
459 # Get filename, we can't use the complete path as only parts of it are
460 # used in the real compiler command.
461 $file =~ m{/([^/\s]+)$};
464 if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) {
465 # Not a non-verbose line, but we still have to skip the current line
466 # as it doesn't contain any compiler commands.
476 my ($flag_refs_ref, $flag_renames_ref, @flags) = @_;
478 my %removes = map { $_ => 1 } @flags;
479 foreach my $flags (@{$flag_refs_ref}) {
481 # Flag found as string.
482 not exists $removes{$_}
483 # Flag found as string representation of regexp.
484 and (not defined $flag_renames_ref->{$_}
485 or not exists $removes{$flag_renames_ref->{$_}})
492 sub compile_flag_regexp {
493 my ($flag_renames_ref, @flags) = @_;
496 foreach my $flag (@flags) {
497 # Store flag name in replacement string for correct flags in messages
498 # with qr//ed flag regexps.
499 $flag_renames_ref->{qr/\s$flag(?:\s|\\)/}
500 = (exists $flag_renames_ref->{$flag})
501 ? $flag_renames_ref->{$flag}
504 # Compile flag regexp for faster execution.
505 push @result, qr/\s$flag(?:\s|\\)/;
510 sub extension_found {
511 my ($extensions_ref, @extensions) = @_;
514 foreach my $extension (@extensions) {
515 if (exists $extensions_ref->{$extension}) {
526 # Parse command line arguments.
528 my $option_version = 0;
530 my $option_bindnow = 0;
531 my @option_ignore_arch = ();
532 my @option_ignore_flag = ();
533 my @option_ignore_arch_flag = ();
534 my @option_ignore_line = ();
535 my @option_ignore_arch_line = ();
537 my $option_arch = undef;
538 my $option_buildd = 0;
540 if (not Getopt::Long::GetOptions(
541 'help|h|?' => \$option_help,
542 'version' => \$option_version,
544 'pie' => \$option_pie,
545 'bindnow' => \$option_bindnow,
546 'all' => \$option_all,
548 'ignore-arch=s' => \@option_ignore_arch,
549 'ignore-flag=s' => \@option_ignore_flag,
550 'ignore-arch-flag=s' => \@option_ignore_arch_flag,
551 'ignore-line=s' => \@option_ignore_line,
552 'ignore-arch-line=s' => \@option_ignore_arch_line,
554 'color' => \$option_color,
555 'arch=s' => \$option_arch,
556 'buildd' => \$option_buildd,
559 Pod::Usage::pod2usage(2);
563 Pod::Usage::pod2usage(1);
565 if ($option_version) {
566 print "blhc $VERSION Copyright (C) 2012 Simon Ruderich
568 This program is free software: you can redistribute it and/or modify
569 it under the terms of the GNU General Public License as published by
570 the Free Software Foundation, either version 3 of the License, or
571 (at your option) any later version.
573 This program is distributed in the hope that it will be useful,
574 but WITHOUT ANY WARRANTY; without even the implied warranty of
575 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
576 GNU General Public License for more details.
578 You should have received a copy of the GNU General Public License
579 along with this program. If not, see <http://www.gnu.org/licenses/>.
585 if (scalar @ARGV == 0) {
587 Pod::Usage::pod2usage(2);
590 # Don't load Term::ANSIColor in buildd mode because Term::ANSIColor is not
591 # installed on Debian's buildds.
592 if (not $option_buildd) {
593 require Term::ANSIColor;
601 # Precompiled ignores for faster lookup.
602 my %option_ignore_arch_flag = ();
603 my %option_ignore_arch_line = ();
605 # Strip flags which should be ignored.
606 if (scalar @option_ignore_flag > 0) {
607 remove_flags(\@flag_refs, \%flag_renames, @option_ignore_flag);
609 # Same for arch specific ignore flags, but only prepare here.
610 if (scalar @option_ignore_arch_flag > 0) {
611 foreach my $ignore (@option_ignore_arch_flag) {
612 my ($ignore_arch, $ignore_flag) = split /:/, $ignore, 2;
614 if (not $ignore_arch or not $ignore_flag) {
615 printf STDERR 'Value "%s" invalid for option ignore-arch-flag '
616 . '("arch:flag" expected)' . "\n", $ignore;
618 Pod::Usage::pod2usage(2);
621 push @{$option_ignore_arch_flag{$ignore_arch}}, $ignore_flag;
625 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
627 foreach my $flags (@flag_refs_all) {
628 @{$flags} = compile_flag_regexp(\%flag_renames, @{$flags});
631 # Precompile ignore line regexps, also anchor at beginning and end of line.
632 foreach my $ignore (@option_ignore_line) {
633 $ignore = qr/^$ignore$/;
635 # Same for arch specific ignore lines.
636 if (scalar @option_ignore_arch_line > 0) {
637 foreach my $ignore (@option_ignore_arch_line) {
638 my ($ignore_arch, $ignore_line) = split /:/, $ignore, 2;
640 if (not $ignore_arch or not $ignore_line) {
641 printf STDERR 'Value "%s" invalid for option ignore-arch-line '
642 . '("arch:line" expected)' . "\n", $ignore;
644 Pod::Usage::pod2usage(2);
647 push @{$option_ignore_arch_line{$ignore_arch}}, qr/^$ignore_line$/;
655 foreach my $file (@ARGV) {
656 print "checking '$file'...\n" if scalar @ARGV > 1;
658 -f $file or die "No such file: $file";
660 open my $fh, '<', $file or die $!;
662 # Architecture of this file.
663 my $arch = $option_arch;
665 # Hardening options. Not all architectures support all hardening options.
666 my $harden_format = 1;
667 my $harden_fortify = 1;
668 my $harden_stack = 1;
669 my $harden_relro = 1;
670 my $harden_bindnow = $option_bindnow; # defaults to 0
671 my $harden_pie = $option_pie; # defaults to 0
673 # Does this build log use ada? Ada also uses gcc as compiler but uses
674 # different CFLAGS. But only perform ada checks if an ada compiler used
675 # for performance reasons.
678 while (my $line = <$fh>) {
679 # Detect architecture automatically unless overridden. For buildd logs
680 # only, doesn't use the dpkg-buildpackage header. Necessary to ignore
681 # build logs which aren't built (wrong architecture, build error,
683 if (not $arch and index($line, 'Architecture: ') == 0) {
684 $arch = substr $line, 14, -1; # -1 to ignore '\n' at the end
687 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
688 # check for hardening flags in buildd mode if an older dpkg-dev is
689 # used. Default flags (-g -O2) are still checked.
691 # Packages which were built before 1.16.1 but used their own hardening
692 # flags are not checked.
694 and index($line, 'Toolchain package versions: ') == 0) {
695 require Dpkg::Version;
696 if (not $line =~ /\bdpkg-dev_(\S+)/
697 or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
707 # The following two versions of CMake in Debian obeyed CPPFLAGS, but
708 # this was later dropped because upstream rejected the patch. Thus
709 # build logs with these versions will have fortify hardening flags
710 # enabled, even though they may be not correctly set and are missing
711 # when build with later CMake versions. Thanks to Aron Xu for letting
713 if (index($line, 'Package versions: ') == 0
714 and $line =~ /\bcmake_(\S+)/
715 and ($1 eq '2.8.7-1' or $1 eq '2.8.7-2')) {
716 if (not $option_buildd) {
717 error_invalid_cmake($1);
718 $exit |= $exit_code{invalid_cmake};
720 print "$buildd_tag{invalid_cmake}|$1|\n";
724 if (index($line, 'Build-Depends: ') == 0) {
725 # If hardening wrapper is used (wraps calls to gcc and adds
726 # hardening flags automatically) we can't perform any checks,
728 if ($line =~ /\bhardening-wrapper\b/) {
729 if (not $option_buildd) {
730 error_hardening_wrapper();
731 $exit |= $exit_code{hardening_wrapper};
733 print "$buildd_tag{hardening_wrapper}||\n";
739 if ($line =~ /\bgnat\b/) {
744 # We skip over unimportant lines at the beginning of the log to
745 # prevent false positives.
746 last if index($line, 'dpkg-buildpackage: ') == 0;
749 # Input lines, contain only the lines with compiler commands.
751 # Non-verbose lines in the input. Used to reduce calls to
752 # is_non_verbose_build() (which is quite slow) in the second loop when
753 # it's already clear if a line is non-verbose or not.
754 my @input_nonverbose = ();
756 my $continuation = 0;
757 my $complete_line = undef;
758 while (my $line = <$fh>) {
759 # And stop at the end of the build log. Package details (reported by
760 # the buildd logs) are not important for us. This also prevents false
762 last if index($line, 'Build finished at ') == 0
763 and $line =~ /^Build finished at \d{8}-\d{4}$/;
765 # Detect architecture automatically unless overridden.
767 and index($line, 'dpkg-buildpackage: host architecture ') == 0) {
768 $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end
771 # Ignore compiler warnings for now.
772 next if $line =~ /$warning_regex/o;
774 if (not $option_buildd and index($line, "\033") != -1) { # \033 = esc
775 # Remove all ANSI color sequences which are sometimes used in
776 # non-verbose builds.
777 $line = Term::ANSIColor::colorstrip($line);
778 # Also strip '\0xf' (delete previous character), used by Elinks'
781 # And "ESC(B" which seems to be used on armhf and hurd (not sure
783 $line =~ s/\033\(B//g;
786 # Check if this line indicates a non verbose build.
787 my $non_verbose = is_non_verbose_build($line);
789 # One line may contain multiple commands (";"). Treat each one as
790 # single line. parse_line() is slow, only use it when necessary.
791 my @line = (index($line, ';') == -1)
794 # Ensure newline at the line end - necessary for
795 # correct parsing later.
798 } Text::ParseWords::parse_line(';', 1, $line);
799 foreach my $line (@line) {
803 # Join lines, but leave the "\" in place so it's clear where
804 # the original line break was.
805 chomp $complete_line;
806 $complete_line .= ' ' . $line;
808 # Line continuation, line ends with "\".
809 if ($line =~ /\\$/) {
811 # Start line continuation.
812 if (not defined $complete_line) {
813 $complete_line = $line;
818 # Use the complete line if a line continuation occurred.
819 if (defined $complete_line) {
820 $line = $complete_line;
821 $complete_line = undef;
824 # Ignore lines with no compiler commands.
825 next if not $non_verbose
826 and not $line =~ /$cc_regex_normal/o;
827 # Ignore lines with no filenames with extensions. May miss some
828 # non-verbose builds (e.g. "gcc -o test" [sic!]), but shouldn't be
829 # a problem as the log will most likely contain other non-verbose
830 # commands which are detected.
831 next if not $non_verbose
832 and not $line =~ /$file_extension_regex/o;
834 # Ignore false positives.
836 # `./configure` output.
837 next if not $non_verbose
838 and $line =~ /^(?:checking|[Cc]onfigure:) /;
839 next if $line =~ /^\s*(?:Host\s+)?(?:C(?:\+\+)?\s+)?
840 [Cc]ompiler[\s.]*:?\s+
842 next if $line =~ /^\s*(?:- )?(?:HOST_)?(?:CC|CXX)\s*=\s*$cc_regex_full\s*$/o;
843 # `moc-qt4`, contains '-I/usr/share/qt4/mkspecs/linux-g++' (or
844 # similar for other architectures) which gets recognized as a
845 # compiler line. Ignore it.
846 next if $line =~ m{^/usr/bin/moc-qt4
848 -I/usr/share/qt4/mkspecs/[a-z]+-g\++(?:-64)?
850 # Ignore false positives when the line contains only CC=gcc but no
852 if ($line =~ /(.*)CC=$cc_regex_full(.*)/o) {
855 next if not $before =~ /$cc_regex_normal/o
856 and not $after =~ /$cc_regex_normal/o;
859 # Check if additional hardening options were used. Used to ensure
860 # they are used for the complete build.
861 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie,
863 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
866 push @input_nonverbose, $non_verbose;
872 # Ignore arch if requested.
873 if (scalar @option_ignore_arch > 0 and $arch) {
874 foreach my $ignore (@option_ignore_arch) {
875 if ($arch eq $ignore) {
876 print "ignoring architecture '$arch'\n";
882 if (scalar @input == 0) {
883 if (not $option_buildd) {
884 print "No compiler commands!\n";
885 $exit |= $exit_code{no_compiler_commands};
887 print "$buildd_tag{no_compiler_commands}||\n";
892 if ($option_buildd) {
893 $statistics{commands} += scalar @input;
896 # Option or auto detected.
898 # The following was partially copied from dpkg-dev 1.16.4.3
899 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
900 # copyright Raphaël Hertzog <hertzog@debian.org>, Kees Cook
901 # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
902 # later. Keep it in sync.
905 my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch);
907 # Disable unsupported hardening options.
908 if ($cpu =~ /^(?:ia64|alpha|mips|mipsel|hppa)$/ or $arch eq 'arm') {
911 if ($cpu =~ /^(?:ia64|hppa|avr32)$/) {
918 my @cflags = @def_cflags;
919 my @cxxflags = @def_cxxflags;
920 my @cppflags = @def_cppflags;
921 my @ldflags = @def_ldflags;
922 # Check the specified hardening options, same order as dpkg-buildflags.
924 @cflags = (@cflags, @def_cflags_pie);
925 @cxxflags = (@cxxflags, @def_cflags_pie);
926 @ldflags = (@ldflags, @def_ldflags_pie);
929 @cflags = (@cflags, @def_cflags_stack);
930 @cxxflags = (@cxxflags, @def_cflags_stack);
932 if ($harden_fortify) {
933 @cflags = (@cflags, @def_cflags_fortify);
934 @cxxflags = (@cxxflags, @def_cflags_fortify);
935 @cppflags = (@cppflags, @def_cppflags_fortify);
937 if ($harden_format) {
938 @cflags = (@cflags, @def_cflags_format);
939 @cxxflags = (@cxxflags, @def_cflags_format);
942 @ldflags = (@ldflags, @def_ldflags_relro);
944 if ($harden_bindnow) {
945 @ldflags = (@ldflags, @def_ldflags_bindnow);
948 # Stores normal CFLAGS when @cflags_ada are temporarily used.
951 my @cflags_ada = @cflags;
952 # Ada doesn't support format hardening flags, see #680117 for more
953 # information. Filter them out if ada is used.
954 if ($ada and $harden_format) {
957 foreach my $flag (@def_cflags_format) {
958 $ok = 0 if $_ eq $flag;
964 # Hack to fix cppflags_fortify_broken() if --ignore-flag
965 # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works
966 # as long as @def_cppflags_fortify contains only one variable.
967 if (scalar @def_cppflags_fortify == 0) {
971 # Ignore flags for this arch if requested.
972 if ($arch and exists $option_ignore_arch_flag{$arch}) {
973 my @local_flag_refs = (\@cflags, \@cxxflags, \@cppflags, \@ldflags);
975 remove_flags(\@local_flag_refs,
977 @{$option_ignore_arch_flag{$arch}});
980 my @ignore_line = @option_ignore_line;
981 # Ignore lines for this arch if requested.
982 if ($arch and exists $option_ignore_arch_line{$arch}) {
983 @ignore_line = (@ignore_line, @{$option_ignore_arch_line{$arch}});
987 for (my $i = 0; $i < scalar @input; $i++) {
988 my $line = $input[$i];
990 # Ignore line if requested.
991 foreach my $ignore (@ignore_line) {
992 next LINE if $line =~ /$ignore/;
996 if ($input_nonverbose[$i]
997 and is_non_verbose_build($line, $input[$i + 1], \$skip)) {
998 if (not $option_buildd) {
999 error_non_verbose_build($line);
1000 $exit |= $exit_code{non_verbose_build};
1002 $statistics{commands_nonverbose}++;
1006 # Even if it's a verbose build, we might have to skip this line.
1009 # Remove everything until and including the compiler command. Makes
1010 # checks easier and faster.
1011 $line =~ s/^.*?$cc_regex//o;
1012 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
1013 # the brace and similar characters at the line end.
1014 $line =~ s/['")]+$//;
1016 # Skip unnecessary tests when only preprocessing.
1017 my $flag_preprocess = 0;
1024 # Preprocess, compile, assemble.
1025 if ($line =~ /\s(-E|-S|-c)\b/) {
1027 $flag_preprocess = 1 if $1 eq '-E';
1028 $compile = 1 if $1 eq '-S' or $1 eq '-c';
1029 # Dependency generation for Makefiles. The other flags (-MF -MG -MP
1030 # -MT -MQ) are always used with -M/-MM.
1031 } elsif ($line =~ /\s(?:-M|-MM)\b/) {
1033 # Otherwise assume we are linking.
1038 # -MD/-MMD also cause dependency generation, but they don't imply -E!
1039 if ($line =~ /\s(?:-MD|-MMD)\b/) {
1041 $flag_preprocess = 0;
1044 # Dependency generation for Makefiles, no preprocessing or other flags
1046 next if $dependency;
1048 # Get all file extensions on this line.
1049 my @extensions = $line =~ /$file_extension_regex/go;
1050 # Ignore all unknown extensions to speedup the search below.
1051 @extensions = grep { exists $extension{$_} } @extensions;
1053 # These file types don't require preprocessing.
1054 if (extension_found(\%extensions_no_preprocess, @extensions)) {
1057 # These file types require preprocessing.
1058 if (extension_found(\%extensions_preprocess, @extensions)) {
1062 if (not $flag_preprocess) {
1063 # If there are source files then it's compiling/linking in one
1064 # step and we must check both. We only check for source files
1065 # here, because header files cause too many false positives.
1066 if (extension_found(\%extensions_compile_link, @extensions)) {
1067 # Assembly files don't need CFLAGS.
1068 if (not extension_found(\%extensions_compile, @extensions)
1069 and extension_found(\%extensions_no_compile, @extensions)) {
1071 # But the rest does.
1075 # No compilable extensions found, either linking or compiling
1078 # If there are also no object files we are just compiling headers
1079 # (.h -> .h.gch). Don't check for linker flags in this case. Due
1080 # to our liberal checks for compiler lines, this also reduces the
1081 # number of false positives considerably.
1083 and not extension_found(\%extensions_object, @extensions)) {
1088 my $compile_cpp = 0;
1089 my $compile_ada = 0;
1090 # Assume CXXFLAGS are required when a C++ file is specified in the
1093 and extension_found(\%extensions_compile_cpp, @extensions)) {
1096 # Ada needs special CFLAGS, use them if only ada files are compiled.
1099 and array_equal(\@extensions,
1100 \@source_no_preprocess_compile_ada)) {
1102 @cflags_backup = @cflags;
1103 @cflags = @cflags_ada;
1106 if ($option_buildd) {
1107 $statistics{preprocess}++ if $preprocess;
1108 $statistics{compile}++ if $compile;
1109 $statistics{compile_cpp}++ if $compile_cpp;
1110 $statistics{link}++ if $link;
1113 # Check hardening flags.
1115 if ($compile and not all_flags_used($line, \@missing, @cflags)
1116 # Libraries linked with -fPIC don't have to (and can't) be
1117 # linked with -fPIE as well. It's no error if only PIE flags
1119 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1120 # Assume dpkg-buildflags returns the correct flags.
1121 and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) {
1122 if (not $option_buildd) {
1123 error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1124 $exit |= $exit_code{flags_missing};
1126 $statistics{compile_missing}++;
1128 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
1129 # Libraries linked with -fPIC don't have to (and can't) be
1130 # linked with -fPIE as well. It's no error if only PIE flags
1132 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1133 # Assume dpkg-buildflags returns the correct flags.
1134 and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) {
1135 if (not $option_buildd) {
1136 error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1137 $exit |= $exit_code{flags_missing};
1139 $statistics{compile_cpp_missing}++;
1143 and (not all_flags_used($line, \@missing, @cppflags)
1144 # The fortify flag might be overwritten, detect that.
1146 and cppflags_fortify_broken($line, \@missing)))
1147 # Assume dpkg-buildflags returns the correct flags.
1148 and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) {
1149 if (not $option_buildd) {
1150 error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1151 $exit |= $exit_code{flags_missing};
1153 $statistics{preprocess_missing}++;
1156 if ($link and not all_flags_used($line, \@missing, @ldflags)
1157 # Same here, -fPIC conflicts with -fPIE.
1158 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
1159 # Assume dpkg-buildflags returns the correct flags.
1160 and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) {
1161 if (not $option_buildd) {
1162 error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1163 $exit |= $exit_code{flags_missing};
1165 $statistics{link_missing}++;
1169 # Restore normal CFLAGS.
1171 @cflags = @cflags_backup;
1176 # Print statistics for buildd mode, only output in this mode.
1177 if ($option_buildd) {
1180 if ($statistics{preprocess_missing}) {
1181 push @warning, sprintf 'CPPFLAGS %d (of %d)',
1182 $statistics{preprocess_missing},
1183 $statistics{preprocess};
1185 if ($statistics{compile_missing}) {
1186 push @warning, sprintf 'CFLAGS %d (of %d)',
1187 $statistics{compile_missing},
1188 $statistics{compile};
1190 if ($statistics{compile_cpp_missing}) {
1191 push @warning, sprintf 'CXXFLAGS %d (of %d)',
1192 $statistics{compile_cpp_missing},
1193 $statistics{compile_cpp};
1195 if ($statistics{link_missing}) {
1196 push @warning, sprintf 'LDFLAGS %d (of %d)',
1197 $statistics{link_missing},
1200 if (scalar @warning) {
1201 local $" = ', '; # array join string
1202 print "$buildd_tag{flags_missing}|@warning missing|\n";
1205 if ($statistics{commands_nonverbose}) {
1206 printf "$buildd_tag{non_verbose_build}|%d (of %d) hidden|\n",
1207 $statistics{commands_nonverbose},
1208 $statistics{commands},
1220 blhc - build log hardening check, checks build logs for missing hardening flags
1224 B<blhc> [I<options>] I<< <dpkg-buildpackage build log file>.. >>
1228 blhc is a small tool which checks build logs for missing hardening flags. It's
1229 licensed under the GPL 3 or later.
1231 It's designed to check build logs generated by Debian's dpkg-buildpackage (or
1232 tools using dpkg-buildpackage like pbuilder or the official buildd build logs)
1233 to help maintainers detect missing hardening flags in their packages.
1235 Only gcc is detected as compiler at the moment. If other compilers support
1236 hardening flags as well, please report them.
1238 If there's no output, no flags are missing and the build log is fine.
1246 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
1249 =item B<--arch> I<architecture>
1251 Set the specific architecture (e.g. amd64, armel, etc.), automatically
1252 disables hardening flags not available on this architecture. Is detected
1253 automatically if dpkg-buildpackage is used.
1257 Force check for all +bindnow hardening flags. By default it's auto detected.
1261 Special mode for buildds when automatically parsing log files. The following
1262 changes are in effect:
1268 Print tags instead of normal warnings, see L</"BUILDD TAGS"> for a list of
1273 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
1278 Don't require Term::ANSIColor.
1282 Return exit code 0, unless there was a error (-I, -W messages don't count as
1289 Use colored (ANSI) output for warning messages.
1291 =item B<--ignore-arch> I<arch>
1293 Ignore build logs from architectures matching I<arch>. I<arch> is a string.
1295 Used to prevent false positives. This option can be specified multiple times.
1297 =item B<--ignore-arch-flag> I<arch>:I<flag>
1299 Like B<--ignore-flag>, but only ignore flag on I<arch>.
1301 =item B<--ignore-arch-line> I<arch>:I<line>
1303 Like B<--ignore-line>, but only ignore line on I<arch>.
1305 =item B<--ignore-flag> I<flag>
1307 Don't print an error when the specific flag is missing in a compiler line.
1308 I<flag> is a string.
1310 Used to prevent false positives. This option can be specified multiple times.
1312 =item B<--ignore-line> I<regex>
1314 Ignore lines matching the given Perl regex. I<regex> is automatically anchored
1315 at the beginning and end of the line to prevent false negatives.
1317 B<NOTE>: Not the input lines are checked, but the lines which are displayed in
1318 warnings (which have line continuation resolved).
1320 Used to prevent false positives. This option can be specified multiple times.
1324 Force check for all +pie hardening flags. By default it's auto detected.
1326 =item B<-h -? --help>
1328 Print available options.
1332 Print version number and license.
1336 Auto detection for B<--pie> and B<--bindnow> only works if at least one
1337 command uses the required hardening flag (e.g. -fPIE). Then it's required for
1338 all other commands as well.
1342 Normal usage, parse a single log file.
1344 blhc path/to/log/file
1346 If there's no output, no flags are missing and the build log is fine.
1348 Parse multiple log files. The exit code is ORed over all files.
1350 blhc path/to/directory/with/log/files/*
1352 Don't treat missing C<-g> as error:
1354 blhc --ignore-flag -g path/to/log/file
1356 Don't treat missing C<-pie> on kfreebsd-amd64 as error:
1358 blhc --ignore-arch-flag kfreebsd-amd64:-pie path/to/log/file
1360 Ignore lines consisting exactly of C<./script gcc file> which would cause a
1363 blhc --ignore-line '\./script gcc file' path/to/log/file
1365 Ignore lines matching C<./script gcc file> somewhere in the line.
1367 blhc --ignore-line '.*\./script gcc file.*' path/to/log/file
1369 Use blhc with pbuilder.
1371 pbuilder path/to/package.dsc | tee path/log/file
1372 blhc path/to/file || echo flags missing
1376 The following tags are used in I<--buildd> mode. In braces the additional data
1381 =item B<I-hardening-wrapper-used>
1383 The package uses hardening-wrapper which intercepts calls to gcc and adds
1384 hardening flags. The build log doesn't contain any hardening flags and thus
1385 can't be checked by blhc.
1387 =item B<W-compiler-flags-hidden> (summary of hidden lines)
1389 Build log contains lines which hide the real compiler flags. For example:
1396 Most of the time either C<export V=1> or C<export verbose=1> in
1397 F<debian/rules> fixes builds with hidden compiler flags. Sometimes C<.SILENT>
1398 in a F<Makefile> must be removed. And as last resort the F<Makefile> must be
1399 patched to remove the C<@>s hiding the real compiler commands.
1401 =item B<W-dpkg-buildflags-missing> (summary of missing flags)
1403 CPPFLAGS, CFLAGS, CXXFLAGS, LDFLAGS missing.
1405 =item B<I-invalid-cmake-used> (version)
1407 By default CMake ignores CPPFLAGS thus missing those hardening flags. Debian
1408 patched CMake in versions 2.8.7-1 and 2.8.7-2 to respect CPPFLAGS, but this
1409 patch was rejected by upstream and later reverted in Debian. Thus those two
1410 versions show correct usage of CPPFLAGS even if the package doesn't correctly
1411 handle them (for example by passing them to CFLAGS). To prevent false
1412 negatives just blacklist those two versions.
1414 =item B<I-no-compiler-commands>
1416 No compiler commands were detected. Either the log contains none or they were
1417 not correctly detected by blhc (please report the bug in this case).
1423 The exit status is a "bit mask", each listed status is ORed when the error
1424 condition occurs to get the result.
1434 No compiler commands were found.
1438 Invalid arguments/options given to blhc.
1446 Missing hardening flags.
1450 Hardening wrapper detected, no tests performed.
1454 Invalid CMake version used. See B<I-invalid-cmake-used> under L</"BUILDD
1455 TAGS"> for a detailed explanation.
1461 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
1463 Thanks to to Bernhard R. Link E<lt>brlink@debian.orgE<gt> and Jaria Alto
1464 E<lt>jari.aalto@cante.netE<gt> for their valuable input and suggestions.
1466 =head1 LICENSE AND COPYRIGHT
1468 Copyright (C) 2012 by Simon Ruderich
1470 This program is free software: you can redistribute it and/or modify
1471 it under the terms of the GNU General Public License as published by
1472 the Free Software Foundation, either version 3 of the License, or
1473 (at your option) any later version.
1475 This program is distributed in the hope that it will be useful,
1476 but WITHOUT ANY WARRANTY; without even the implied warranty of
1477 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1478 GNU General Public License for more details.
1480 You should have received a copy of the GNU General Public License
1481 along with this program. If not, see <http://www.gnu.org/licenses/>.
1485 L<hardening-check(1)>, L<dpkg-buildflags(1)>