3 # Build log hardening check, checks build logs for missing hardening flags.
5 # Copyright (C) 2012-2013 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 = '0.04';
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 (and compiled to
180 # real regexps below for better execution speed).
185 my @def_cflags_format = (
186 '-Wformat(?:=2)?', # -Wformat=2 implies -Wformat, accept it too
187 '-Werror=format-security', # implies -Wformat-security
189 my @def_cflags_fortify = (
190 # fortify needs at least -O1, but -O2 is recommended anyway
192 my @def_cflags_stack = (
194 '--param[= ]ssp-buffer-size=4',
196 my @def_cflags_pie = (
202 # @def_cxxflags_* is the same as @def_cflags_*.
203 my @def_cppflags = ();
204 my @def_cppflags_fortify = (
205 '-D_FORTIFY_SOURCE=2', # must be first, see cppflags_fortify_broken()
206 # If you add another flag fix hack below (search for "Hack to fix").
208 my @def_cppflags_fortify_bad = (
209 # These flags may overwrite -D_FORTIFY_SOURCE=2.
211 '-D_FORTIFY_SOURCE=0',
212 '-D_FORTIFY_SOURCE=1',
214 my @def_ldflags = ();
215 my @def_ldflags_relro = (
218 my @def_ldflags_bindnow = (
221 my @def_ldflags_pie = (
225 my @def_ldflags_pic = (
230 # References to all flags checked by the flag checker.
234 \@def_cflags_fortify,
239 \@def_cppflags_fortify,
242 \@def_ldflags_bindnow,
245 # References to all used flags.
246 my @flag_refs_all = (
248 \@def_cppflags_fortify_bad,
251 # Renaming rules for the output so the regex parts are not visible. Also
252 # stores string values of flag regexps above, see compile_flag_regexp().
254 '-O(?:2|3)' => '-O2',
255 '-Wformat(?:=2)?' => '-Wformat',
256 '--param[= ]ssp-buffer-size=4' => '--param=ssp-buffer-size=4',
257 '-Wl,(?:-z,)?relro' => '-Wl,-z,relro',
258 '-Wl,(?:-z,)?now' => '-Wl,-z,now',
262 no_compiler_commands => 1 << 0,
263 # used by POD::Usage => 1 << 1,
264 non_verbose_build => 1 << 2,
265 flags_missing => 1 << 3,
266 hardening_wrapper => 1 << 4,
267 invalid_cmake => 1 << 5,
271 no_compiler_commands => 'I-no-compiler-commands',
272 non_verbose_build => 'W-compiler-flags-hidden',
273 flags_missing => 'W-dpkg-buildflags-missing',
274 hardening_wrapper => 'I-hardening-wrapper-used',
275 invalid_cmake => 'I-invalid-cmake-used',
278 # Statistics of missing flags and non-verbose build commands. Used for
282 preprocess_missing => 0,
284 compile_missing => 0,
286 compile_cpp_missing => 0,
290 commands_nonverbose => 0,
293 # Use colored (ANSI) output?
299 # Only works for single-level arrays with no undef values. Thanks to perlfaq4.
301 my ($first_ref, $second_ref) = @_;
303 return 0 if scalar @{$first_ref} != scalar @{$second_ref};
305 my $length = scalar @{$first_ref};
306 for (my $i = 0; $i < $length; $i++) {
307 return 0 if $first_ref->[$i] ne $second_ref->[$i];
314 my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_;
316 # Get string value of qr//-escaped regexps and if requested rename them.
317 my @missing_flags = map {
318 $flag_renames_ref->{$_}
319 } @{$missing_flags_ref};
321 my $flags = join ' ', @missing_flags;
322 printf '%s (%s)%s %s',
323 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
328 sub error_non_verbose_build {
332 error_color('NONVERBOSE BUILD', 'red'),
333 error_color(':', 'yellow'),
338 sub error_invalid_cmake {
342 error_color('INVALID CMAKE', 'red'),
343 error_color(':', 'yellow'),
348 sub error_hardening_wrapper {
350 error_color('HARDENING WRAPPER', 'red'),
351 error_color(':', 'yellow'),
352 'no checks possible, aborting';
357 my ($message, $color) = @_;
360 return Term::ANSIColor::colored($message, $color);
367 my ($line, @flags) = @_;
369 foreach my $flag (@flags) {
370 return 1 if $line =~ /$flag/;
376 my ($line, $missing_flags_ref, @flags) = @_;
378 my @missing_flags = ();
379 foreach my $flag (@flags) {
380 if (not $line =~ /$flag/) {
381 push @missing_flags, $flag;
385 return 1 if scalar @missing_flags == 0;
387 @{$missing_flags_ref} = @missing_flags;
391 sub cppflags_fortify_broken {
392 my ($line, $missing_flags) = @_;
394 # This doesn't take the position into account, but is a simple solution.
395 # And if the build system tries to force -D_FORTIFY_SOURCE=0/1, something
398 if (any_flags_used($line, @def_cppflags_fortify_bad)) {
399 # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2!
400 push @{$missing_flags}, $def_cppflags_fortify[0];
407 # Modifies $missing_flags_ref array.
408 sub pic_pie_conflict {
409 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
411 return 0 if not $pie;
412 return 0 if not any_flags_used($line, @def_ldflags_pic);
414 my %flags = map { $_ => 1 } @flags_pie;
416 # Remove all PIE flags from @missing_flags as they are not required with
419 not exists $flags{$_}
420 } @{$missing_flags_ref};
421 @{$missing_flags_ref} = @result;
423 # We got a conflict when no flags are left, thus only PIE flags were
424 # missing. If other flags were missing abort because the conflict is not
426 return scalar @result == 0;
429 sub is_non_verbose_build {
430 my ($line, $next_line, $skip_ref) = @_;
432 if (not (index($line, 'checking if you want to see long compiling messages... no') == 0
433 or $line =~ /^\s*\[?(?:CC|CCLD|C\+\+|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
434 or $line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/
435 or $line =~ /^\s*[Bb]uilding (?:program|shared library)\s+(.+?)$/
436 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
442 # C++ compiler setting.
443 return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/;
444 return 0 if $line =~ /^\s*C\+\+ Library: stdc\+\+$/;
445 # "Compiling" with no file name.
446 if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) {
447 # $file_extension_regex may need spaces around the filename.
448 return 0 if not " $1 " =~ /$file_extension_regex/o;
453 # On the first pass we only check if this line is verbose or not.
454 return 1 if not defined $next_line;
456 # Second pass, we have access to the next line.
459 # CMake and other build systems print the non-verbose messages also when
460 # building verbose. If a compiler and the file name occurs in the next
461 # line, treat it as verbose build.
463 # Get filename, we can't use the complete path as only parts of it are
464 # used in the real compiler command.
465 $file =~ m{/([^/\s]+)$};
468 if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) {
469 # Not a non-verbose line, but we still have to skip the current line
470 # as it doesn't contain any compiler commands.
479 # Remove @flags from $flag_refs_ref, and $flag_renames_ref.
481 my ($flag_refs_ref, $flag_renames_ref, @flags) = @_;
483 my %removes = map { $_ => 1 } @flags;
484 foreach my $flags (@{$flag_refs_ref}) {
486 # Flag found as string.
487 not exists $removes{$_}
488 # Flag found as string representation of regexp.
489 and (not defined $flag_renames_ref->{$_}
490 or not exists $removes{$flag_renames_ref->{$_}})
497 # Modifies $flag_renames_ref hash.
498 sub compile_flag_regexp {
499 my ($flag_renames_ref, @flags) = @_;
502 foreach my $flag (@flags) {
503 # Compile flag regexp for faster execution.
504 my $regex = qr/\s$flag(?:\s|\\)/;
506 # Store flag name in replacement string for correct flags in messages
507 # with qr//ed flag regexps.
508 $flag_renames_ref->{$regex}
509 = (exists $flag_renames_ref->{$flag})
510 ? $flag_renames_ref->{$flag}
513 push @result, $regex;
518 # Does any extension in @extensions exist in %{$extensions_ref}?
519 sub extension_found {
520 my ($extensions_ref, @extensions) = @_;
522 foreach my $extension (@extensions) {
523 if (exists $extensions_ref->{$extension}) {
533 # Parse command line arguments.
535 my $option_version = 0;
537 my $option_bindnow = 0;
538 my @option_ignore_arch = ();
539 my @option_ignore_flag = ();
540 my @option_ignore_arch_flag = ();
541 my @option_ignore_line = ();
542 my @option_ignore_arch_line = ();
544 my $option_arch = undef;
545 my $option_buildd = 0;
547 if (not Getopt::Long::GetOptions(
548 'help|h|?' => \$option_help,
549 'version' => \$option_version,
551 'pie' => \$option_pie,
552 'bindnow' => \$option_bindnow,
553 'all' => \$option_all,
555 'ignore-arch=s' => \@option_ignore_arch,
556 'ignore-flag=s' => \@option_ignore_flag,
557 'ignore-arch-flag=s' => \@option_ignore_arch_flag,
558 'ignore-line=s' => \@option_ignore_line,
559 'ignore-arch-line=s' => \@option_ignore_arch_line,
561 'color' => \$option_color,
562 'arch=s' => \$option_arch,
563 'buildd' => \$option_buildd,
566 Pod::Usage::pod2usage(2);
570 Pod::Usage::pod2usage(1);
572 if ($option_version) {
574 blhc $VERSION Copyright (C) 2012-2013 Simon Ruderich
576 This program is free software: you can redistribute it and/or modify
577 it under the terms of the GNU General Public License as published by
578 the Free Software Foundation, either version 3 of the License, or
579 (at your option) any later version.
581 This program is distributed in the hope that it will be useful,
582 but WITHOUT ANY WARRANTY; without even the implied warranty of
583 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
584 GNU General Public License for more details.
586 You should have received a copy of the GNU General Public License
587 along with this program. If not, see <http://www.gnu.org/licenses/>.
593 if (scalar @ARGV == 0) {
595 Pod::Usage::pod2usage(2);
598 # Don't load Term::ANSIColor in buildd mode because Term::ANSIColor is not
599 # installed on Debian's buildds.
600 if (not $option_buildd) {
601 require Term::ANSIColor;
609 # Precompiled ignores for faster lookup.
610 my %option_ignore_arch_flag = ();
611 my %option_ignore_arch_line = ();
613 # Strip flags which should be ignored.
614 if (scalar @option_ignore_flag > 0) {
615 remove_flags(\@flag_refs, \%flag_renames, @option_ignore_flag);
617 # Same for arch specific ignore flags, but only prepare here.
618 if (scalar @option_ignore_arch_flag > 0) {
619 foreach my $ignore (@option_ignore_arch_flag) {
620 my ($ignore_arch, $ignore_flag) = split /:/, $ignore, 2;
622 if (not $ignore_arch or not $ignore_flag) {
623 printf STDERR 'Value "%s" invalid for option ignore-arch-flag '
624 . '("arch:flag" expected)' . "\n", $ignore;
626 Pod::Usage::pod2usage(2);
629 push @{$option_ignore_arch_flag{$ignore_arch}}, $ignore_flag;
633 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
635 foreach my $flags (@flag_refs_all) {
636 @{$flags} = compile_flag_regexp(\%flag_renames, @{$flags});
639 # Precompile ignore line regexps, also anchor at beginning and end of line.
640 foreach my $ignore (@option_ignore_line) {
641 $ignore = qr/^$ignore$/;
643 # Same for arch specific ignore lines.
644 if (scalar @option_ignore_arch_line > 0) {
645 foreach my $ignore (@option_ignore_arch_line) {
646 my ($ignore_arch, $ignore_line) = split /:/, $ignore, 2;
648 if (not $ignore_arch or not $ignore_line) {
649 printf STDERR 'Value "%s" invalid for option ignore-arch-line '
650 . '("arch:line" expected)' . "\n", $ignore;
652 Pod::Usage::pod2usage(2);
655 push @{$option_ignore_arch_line{$ignore_arch}}, qr/^$ignore_line$/;
663 foreach my $file (@ARGV) {
664 print "checking '$file'...\n" if scalar @ARGV > 1;
666 -f $file or die "No such file: $file";
668 open my $fh, '<', $file or die $!;
670 # Architecture of this file.
671 my $arch = $option_arch;
673 # Hardening options. Not all architectures support all hardening options.
674 my $harden_format = 1;
675 my $harden_fortify = 1;
676 my $harden_stack = 1;
677 my $harden_relro = 1;
678 my $harden_bindnow = $option_bindnow; # defaults to 0
679 my $harden_pie = $option_pie; # defaults to 0
681 # Does this build log use ada? Ada also uses gcc as compiler but uses
682 # different CFLAGS. But only perform ada checks if an ada compiler used
683 # for performance reasons.
686 while (my $line = <$fh>) {
687 # Detect architecture automatically unless overridden. For buildd logs
688 # only, doesn't use the dpkg-buildpackage header. Necessary to ignore
689 # build logs which aren't built (wrong architecture, build error,
692 if (index($line, 'Build Architecture: ') == 0) {
693 $arch = substr $line, 20, -1; # -1 to ignore '\n' at the end
694 # For old logs (sbuild << 0.63.0-1).
695 } elsif (index($line, 'Architecture: ') == 0) {
696 $arch = substr $line, 14, -1; # -1 to ignore '\n' at the end
700 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
701 # check for hardening flags in buildd mode if an older dpkg-dev is
702 # used. Default flags (-g -O2) are still checked.
704 # Packages which were built before 1.16.1 but used their own hardening
705 # flags are not checked.
707 and index($line, 'Toolchain package versions: ') == 0) {
708 require Dpkg::Version;
709 if (not $line =~ /\bdpkg-dev_(\S+)/
710 or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
720 # The following two versions of CMake in Debian obeyed CPPFLAGS, but
721 # this was later dropped because upstream rejected the patch. Thus
722 # build logs with these versions will have fortify hardening flags
723 # enabled, even though they may be not correctly set and are missing
724 # when build with later CMake versions. Thanks to Aron Xu for letting
726 if (index($line, 'Package versions: ') == 0
727 and $line =~ /\bcmake_(\S+)/
728 and ($1 eq '2.8.7-1' or $1 eq '2.8.7-2')) {
729 if (not $option_buildd) {
730 error_invalid_cmake($1);
731 $exit |= $exit_code{invalid_cmake};
733 print "$buildd_tag{invalid_cmake}|$1|\n";
737 # Debian's build daemons use "Filtered Build-Depends:" (or just
738 # "Build-Depends:" in older versions) for the build dependencies, but
739 # pbuilder uses "Depends:"; support both.
740 if (index($line, 'Filtered Build-Depends: ') == 0
741 or index($line, 'Build-Depends: ') == 0
742 or index($line, 'Depends: ') == 0) {
743 # If hardening wrapper is used (wraps calls to gcc and adds
744 # hardening flags automatically) we can't perform any checks,
746 if ($line =~ /\bhardening-wrapper\b/) {
747 if (not $option_buildd) {
748 error_hardening_wrapper();
749 $exit |= $exit_code{hardening_wrapper};
751 print "$buildd_tag{hardening_wrapper}||\n";
757 if ($line =~ /\bgnat\b/) {
762 # We skip over unimportant lines at the beginning of the log to
763 # prevent false positives.
764 last if index($line, 'dpkg-buildpackage: ') == 0;
767 # Input lines, contain only the lines with compiler commands.
769 # Non-verbose lines in the input. Used to reduce calls to
770 # is_non_verbose_build() (which is quite slow) in the second loop when
771 # it's already clear if a line is non-verbose or not.
772 my @input_nonverbose = ();
774 my $continuation = 0;
775 my $complete_line = undef;
776 while (my $line = <$fh>) {
777 # And stop at the end of the build log. Package details (reported by
778 # the buildd logs) are not important for us. This also prevents false
780 last if index($line, 'Build finished at ') == 0
781 and $line =~ /^Build finished at \d{8}-\d{4}$/;
783 # Detect architecture automatically unless overridden.
785 and index($line, 'dpkg-buildpackage: host architecture ') == 0) {
786 $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end
788 # Old buildd logs use e.g. "host architecture is alpha", remove
789 # the "is", otherwise debarch_to_debtriplet() will not detect the
791 if (index($arch, 'is ') == 0) {
792 $arch = substr $arch, 3;
796 # Ignore compiler warnings for now.
797 next if $line =~ /$warning_regex/o;
799 if (not $option_buildd and index($line, "\033") != -1) { # \033 = esc
800 # Remove all ANSI color sequences which are sometimes used in
801 # non-verbose builds.
802 $line = Term::ANSIColor::colorstrip($line);
803 # Also strip '\0xf' (delete previous character), used by Elinks'
806 # And "ESC(B" which seems to be used on armhf and hurd (not sure
808 $line =~ s/\033\(B//g;
811 # Check if this line indicates a non verbose build.
812 my $non_verbose = is_non_verbose_build($line);
814 # One line may contain multiple commands (";"). Treat each one as
815 # single line. parse_line() is slow, only use it when necessary.
816 my @line = (index($line, ';') == -1)
819 # Ensure newline at the line end - necessary for
820 # correct parsing later.
823 } Text::ParseWords::parse_line(';', 1, $line);
824 foreach my $line (@line) {
828 # Join lines, but leave the "\" in place so it's clear where
829 # the original line break was.
830 chomp $complete_line;
831 $complete_line .= ' ' . $line;
833 # Line continuation, line ends with "\".
834 if ($line =~ /\\$/) {
836 # Start line continuation.
837 if (not defined $complete_line) {
838 $complete_line = $line;
843 # Use the complete line if a line continuation occurred.
844 if (defined $complete_line) {
845 $line = $complete_line;
846 $complete_line = undef;
849 # Ignore lines with no compiler commands.
850 next if not $non_verbose
851 and not $line =~ /$cc_regex_normal/o;
852 # Ignore lines with no filenames with extensions. May miss some
853 # non-verbose builds (e.g. "gcc -o test" [sic!]), but shouldn't be
854 # a problem as the log will most likely contain other non-verbose
855 # commands which are detected.
856 next if not $non_verbose
857 and not $line =~ /$file_extension_regex/o;
859 # Ignore false positives.
861 # `./configure` output.
862 next if not $non_verbose
863 and $line =~ /^(?:checking|[Cc]onfigure:) /;
864 next if $line =~ /^\s*(?:Host\s+)?(?:C(?:\+\+)?\s+)?
865 [Cc]ompiler[\s.]*:?\s+
867 next if $line =~ m{^\s*(?:-\s)?(?:HOST_)?(?:CC|CXX)
868 \s*=\s*$cc_regex_full
869 # optional compiler options, don't allow
870 # "everything" here to prevent false negatives
871 \s*(?:\s-\S+)*\s*$}xo;
872 # `moc-qt4`/`moc-qt5` contain '-I.../linux-g++' in their command
873 # line (or similar for other architectures) which gets recognized
874 # as a compiler line, but `moc-qt*` is only a preprocessor for Qt
875 # C++ files. No hardening flags are relevant during this step,
876 # thus ignore `moc-qt*` lines. The resulting files will be
877 # compiled in a separate step (and therefore checked).
878 next if $line =~ m{^\S+/bin/moc(?:-qt[45])?
880 -I\S+/mkspecs/[a-z]+-g\++(?:-64)?
882 # Ignore false positives when the line contains only CC=gcc but no
884 if ($line =~ /(.*)CC=$cc_regex_full(.*)/o) {
887 next if not $before =~ /$cc_regex_normal/o
888 and not $after =~ /$cc_regex_normal/o;
891 # Check if additional hardening options were used. Used to ensure
892 # they are used for the complete build.
893 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie,
895 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
898 push @input_nonverbose, $non_verbose;
904 # Ignore arch if requested.
905 if (scalar @option_ignore_arch > 0 and $arch) {
906 foreach my $ignore (@option_ignore_arch) {
907 if ($arch eq $ignore) {
908 print "ignoring architecture '$arch'\n";
914 if (scalar @input == 0) {
915 if (not $option_buildd) {
916 print "No compiler commands!\n";
917 $exit |= $exit_code{no_compiler_commands};
919 print "$buildd_tag{no_compiler_commands}||\n";
924 if ($option_buildd) {
925 $statistics{commands} += scalar @input;
928 # Option or auto detected.
930 # The following was partially copied from dpkg-dev 1.17.1
931 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
932 # copyright Raphaël Hertzog <hertzog@debian.org>, Kees Cook
933 # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
934 # later. Keep it in sync.
937 my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch);
939 # Disable unsupported hardening options.
940 if ($os !~ /^(?:linux|knetbsd|hurd)$/ or
941 $cpu =~ /^(?:hppa|mips|mipsel|avr32)$/) {
944 if ($cpu =~ /^(?:ia64|alpha|mips|mipsel|hppa|arm64)$/
948 if ($cpu =~ /^(?:ia64|hppa|avr32)$/) {
955 my @cflags = @def_cflags;
956 my @cxxflags = @def_cxxflags;
957 my @cppflags = @def_cppflags;
958 my @ldflags = @def_ldflags;
959 # Check the specified hardening options, same order as dpkg-buildflags.
961 @cflags = (@cflags, @def_cflags_pie);
962 @cxxflags = (@cxxflags, @def_cflags_pie);
963 @ldflags = (@ldflags, @def_ldflags_pie);
966 @cflags = (@cflags, @def_cflags_stack);
967 @cxxflags = (@cxxflags, @def_cflags_stack);
969 if ($harden_fortify) {
970 @cflags = (@cflags, @def_cflags_fortify);
971 @cxxflags = (@cxxflags, @def_cflags_fortify);
972 @cppflags = (@cppflags, @def_cppflags_fortify);
974 if ($harden_format) {
975 @cflags = (@cflags, @def_cflags_format);
976 @cxxflags = (@cxxflags, @def_cflags_format);
979 @ldflags = (@ldflags, @def_ldflags_relro);
981 if ($harden_bindnow) {
982 @ldflags = (@ldflags, @def_ldflags_bindnow);
985 # Stores normal CFLAGS when @cflags_ada are temporarily used.
987 # Ada CFLAGS, only set if ada is used.
989 # Ada doesn't support format hardening flags, see #680117 for more
990 # information. Filter them out if ada is used.
991 if ($ada and $harden_format) {
994 foreach my $flag (@def_cflags_format) {
995 $ok = 0 if $_ eq $flag;
1001 # Hack to fix cppflags_fortify_broken() if --ignore-flag
1002 # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works
1003 # as long as @def_cppflags_fortify contains only one variable.
1004 if (scalar @def_cppflags_fortify == 0) {
1005 $harden_fortify = 0;
1008 # Ignore flags for this arch if requested.
1009 if ($arch and exists $option_ignore_arch_flag{$arch}) {
1010 my @local_flag_refs = (\@cflags, \@cxxflags, \@cppflags, \@ldflags);
1012 remove_flags(\@local_flag_refs,
1014 @{$option_ignore_arch_flag{$arch}});
1017 my @ignore_line = @option_ignore_line;
1018 # Ignore lines for this arch if requested.
1019 if ($arch and exists $option_ignore_arch_line{$arch}) {
1020 @ignore_line = (@ignore_line, @{$option_ignore_arch_line{$arch}});
1024 for (my $i = 0; $i < scalar @input; $i++) {
1025 my $line = $input[$i];
1027 # Ignore line if requested.
1028 foreach my $ignore (@ignore_line) {
1029 next LINE if $line =~ /$ignore/;
1033 if ($input_nonverbose[$i]
1034 and is_non_verbose_build($line, $input[$i + 1], \$skip)) {
1035 if (not $option_buildd) {
1036 error_non_verbose_build($line);
1037 $exit |= $exit_code{non_verbose_build};
1039 $statistics{commands_nonverbose}++;
1043 # Even if it's a verbose build, we might have to skip this line (see
1044 # is_non_verbose_build()).
1047 # Remove everything until and including the compiler command. Makes
1048 # checks easier and faster.
1049 $line =~ s/^.*?$cc_regex//o;
1050 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
1051 # the brace and similar characters at the line end.
1052 $line =~ s/['")]+$//;
1054 # Skip unnecessary tests when only preprocessing.
1055 my $flag_preprocess = 0;
1062 # Preprocess, compile, assemble.
1063 if ($line =~ /\s(-E|-S|-c)\b/) {
1065 $flag_preprocess = 1 if $1 eq '-E';
1066 $compile = 1 if $1 eq '-S' or $1 eq '-c';
1067 # Dependency generation for Makefiles. The other flags (-MF -MG -MP
1068 # -MT -MQ) are always used with -M/-MM.
1069 } elsif ($line =~ /\s(?:-M|-MM)\b/) {
1071 # Otherwise assume we are linking.
1076 # -MD/-MMD also cause dependency generation, but they don't imply -E!
1077 if ($line =~ /\s(?:-MD|-MMD)\b/) {
1079 $flag_preprocess = 0;
1082 # Dependency generation for Makefiles, no preprocessing or other flags
1084 next if $dependency;
1086 # Get all file extensions on this line.
1087 my @extensions = $line =~ /$file_extension_regex/go;
1088 # Ignore all unknown extensions to speedup the search below.
1089 @extensions = grep { exists $extension{$_} } @extensions;
1091 # These file types don't require preprocessing.
1092 if (extension_found(\%extensions_no_preprocess, @extensions)) {
1095 # These file types require preprocessing.
1096 if (extension_found(\%extensions_preprocess, @extensions)) {
1100 if (not $flag_preprocess) {
1101 # If there are source files then it's compiling/linking in one
1102 # step and we must check both. We only check for source files
1103 # here, because header files cause too many false positives.
1104 if (extension_found(\%extensions_compile_link, @extensions)) {
1105 # Assembly files don't need CFLAGS.
1106 if (not extension_found(\%extensions_compile, @extensions)
1107 and extension_found(\%extensions_no_compile, @extensions)) {
1109 # But the rest does.
1113 # No compilable extensions found, either linking or compiling
1116 # If there are also no object files we are just compiling headers
1117 # (.h -> .h.gch). Don't check for linker flags in this case. Due
1118 # to our liberal checks for compiler lines, this also reduces the
1119 # number of false positives considerably.
1121 and not extension_found(\%extensions_object, @extensions)) {
1126 my $compile_cpp = 0;
1127 my $compile_ada = 0;
1128 # Assume CXXFLAGS are required when a C++ file is specified in the
1131 and extension_found(\%extensions_compile_cpp, @extensions)) {
1134 # Ada needs special CFLAGS, use them if only ada files are compiled.
1137 and array_equal(\@extensions,
1138 \@source_no_preprocess_compile_ada)) {
1140 @cflags_backup = @cflags;
1141 @cflags = @cflags_ada;
1144 if ($option_buildd) {
1145 $statistics{preprocess}++ if $preprocess;
1146 $statistics{compile}++ if $compile;
1147 $statistics{compile_cpp}++ if $compile_cpp;
1148 $statistics{link}++ if $link;
1151 # Check hardening flags.
1153 if ($compile and not all_flags_used($line, \@missing, @cflags)
1154 # Libraries linked with -fPIC don't have to (and can't) be
1155 # linked with -fPIE as well. It's no error if only PIE flags
1157 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1158 # Assume dpkg-buildflags returns the correct flags.
1159 and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) {
1160 if (not $option_buildd) {
1161 error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1162 $exit |= $exit_code{flags_missing};
1164 $statistics{compile_missing}++;
1166 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
1167 # Libraries linked with -fPIC don't have to (and can't) be
1168 # linked with -fPIE as well. It's no error if only PIE flags
1170 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1171 # Assume dpkg-buildflags returns the correct flags.
1172 and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) {
1173 if (not $option_buildd) {
1174 error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1175 $exit |= $exit_code{flags_missing};
1177 $statistics{compile_cpp_missing}++;
1181 and (not all_flags_used($line, \@missing, @cppflags)
1182 # The fortify flag might be overwritten, detect that.
1184 and cppflags_fortify_broken($line, \@missing)))
1185 # Assume dpkg-buildflags returns the correct flags.
1186 and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) {
1187 if (not $option_buildd) {
1188 error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1189 $exit |= $exit_code{flags_missing};
1191 $statistics{preprocess_missing}++;
1194 if ($link and not all_flags_used($line, \@missing, @ldflags)
1195 # Same here, -fPIC conflicts with -fPIE.
1196 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
1197 # Assume dpkg-buildflags returns the correct flags.
1198 and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) {
1199 if (not $option_buildd) {
1200 error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1201 $exit |= $exit_code{flags_missing};
1203 $statistics{link_missing}++;
1207 # Restore normal CFLAGS.
1209 @cflags = @cflags_backup;
1214 # Print statistics for buildd mode, only output in this mode.
1215 if ($option_buildd) {
1218 if ($statistics{preprocess_missing}) {
1219 push @warning, sprintf 'CPPFLAGS %d (of %d)',
1220 $statistics{preprocess_missing},
1221 $statistics{preprocess};
1223 if ($statistics{compile_missing}) {
1224 push @warning, sprintf 'CFLAGS %d (of %d)',
1225 $statistics{compile_missing},
1226 $statistics{compile};
1228 if ($statistics{compile_cpp_missing}) {
1229 push @warning, sprintf 'CXXFLAGS %d (of %d)',
1230 $statistics{compile_cpp_missing},
1231 $statistics{compile_cpp};
1233 if ($statistics{link_missing}) {
1234 push @warning, sprintf 'LDFLAGS %d (of %d)',
1235 $statistics{link_missing},
1238 if (scalar @warning) {
1239 local $" = ', '; # array join string
1240 print "$buildd_tag{flags_missing}|@warning missing|\n";
1243 if ($statistics{commands_nonverbose}) {
1244 printf "$buildd_tag{non_verbose_build}|%d (of %d) hidden|\n",
1245 $statistics{commands_nonverbose},
1246 $statistics{commands},
1258 blhc - build log hardening check, checks build logs for missing hardening flags
1262 B<blhc> [I<options>] I<< <dpkg-buildpackage build log file>.. >>
1266 blhc is a small tool which checks build logs for missing hardening flags. It's
1267 licensed under the GPL 3 or later.
1269 It's designed to check build logs generated by Debian's dpkg-buildpackage (or
1270 tools using dpkg-buildpackage like pbuilder or the official buildd build logs)
1271 to help maintainers detect missing hardening flags in their packages.
1273 Only gcc is detected as compiler at the moment. If other compilers support
1274 hardening flags as well, please report them.
1276 If there's no output, no flags are missing and the build log is fine.
1284 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
1287 =item B<--arch> I<architecture>
1289 Set the specific architecture (e.g. amd64, armel, etc.), automatically
1290 disables hardening flags not available on this architecture. Is detected
1291 automatically if dpkg-buildpackage is used.
1295 Force check for all +bindnow hardening flags. By default it's auto detected.
1299 Special mode for buildds when automatically parsing log files. The following
1300 changes are in effect:
1306 Print tags instead of normal warnings, see L</"BUILDD TAGS"> for a list of
1311 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
1316 Don't require Term::ANSIColor.
1320 Return exit code 0, unless there was a error (-I, -W messages don't count as
1327 Use colored (ANSI) output for warning messages.
1329 =item B<--ignore-arch> I<arch>
1331 Ignore build logs from architectures matching I<arch>. I<arch> is a string.
1333 Used to prevent false positives. This option can be specified multiple times.
1335 =item B<--ignore-arch-flag> I<arch>:I<flag>
1337 Like B<--ignore-flag>, but only ignore flag on I<arch>.
1339 =item B<--ignore-arch-line> I<arch>:I<line>
1341 Like B<--ignore-line>, but only ignore line on I<arch>.
1343 =item B<--ignore-flag> I<flag>
1345 Don't print an error when the specific flag is missing in a compiler line.
1346 I<flag> is a string.
1348 Used to prevent false positives. This option can be specified multiple times.
1350 =item B<--ignore-line> I<regex>
1352 Ignore lines matching the given Perl regex. I<regex> is automatically anchored
1353 at the beginning and end of the line to prevent false negatives.
1355 B<NOTE>: Not the input lines are checked, but the lines which are displayed in
1356 warnings (which have line continuation resolved).
1358 Used to prevent false positives. This option can be specified multiple times.
1362 Force check for all +pie hardening flags. By default it's auto detected.
1364 =item B<-h -? --help>
1366 Print available options.
1370 Print version number and license.
1374 Auto detection for B<--pie> and B<--bindnow> only works if at least one
1375 command uses the required hardening flag (e.g. -fPIE). Then it's required for
1376 all other commands as well.
1380 Normal usage, parse a single log file.
1382 blhc path/to/log/file
1384 If there's no output, no flags are missing and the build log is fine.
1386 Parse multiple log files. The exit code is ORed over all files.
1388 blhc path/to/directory/with/log/files/*
1390 Don't treat missing C<-g> as error:
1392 blhc --ignore-flag -g path/to/log/file
1394 Don't treat missing C<-pie> on kfreebsd-amd64 as error:
1396 blhc --ignore-arch-flag kfreebsd-amd64:-pie path/to/log/file
1398 Ignore lines consisting exactly of C<./script gcc file> which would cause a
1401 blhc --ignore-line '\./script gcc file' path/to/log/file
1403 Ignore lines matching C<./script gcc file> somewhere in the line.
1405 blhc --ignore-line '.*\./script gcc file.*' path/to/log/file
1407 Use blhc with pbuilder.
1409 pbuilder path/to/package.dsc | tee path/log/file
1410 blhc path/to/file || echo flags missing
1414 The following tags are used in I<--buildd> mode. In braces the additional data
1419 =item B<I-hardening-wrapper-used>
1421 The package uses hardening-wrapper which intercepts calls to gcc and adds
1422 hardening flags. The build log doesn't contain any hardening flags and thus
1423 can't be checked by blhc.
1425 =item B<W-compiler-flags-hidden> (summary of hidden lines)
1427 Build log contains lines which hide the real compiler flags. For example:
1434 Most of the time either C<export V=1> or C<export verbose=1> in
1435 F<debian/rules> fixes builds with hidden compiler flags. Sometimes C<.SILENT>
1436 in a F<Makefile> must be removed. And as last resort the F<Makefile> must be
1437 patched to remove the C<@>s hiding the real compiler commands.
1439 =item B<W-dpkg-buildflags-missing> (summary of missing flags)
1441 CPPFLAGS, CFLAGS, CXXFLAGS, LDFLAGS missing.
1443 =item B<I-invalid-cmake-used> (version)
1445 By default CMake ignores CPPFLAGS thus missing those hardening flags. Debian
1446 patched CMake in versions 2.8.7-1 and 2.8.7-2 to respect CPPFLAGS, but this
1447 patch was rejected by upstream and later reverted in Debian. Thus those two
1448 versions show correct usage of CPPFLAGS even if the package doesn't correctly
1449 handle them (for example by passing them to CFLAGS). To prevent false
1450 negatives just blacklist those two versions.
1452 =item B<I-no-compiler-commands>
1454 No compiler commands were detected. Either the log contains none or they were
1455 not correctly detected by blhc (please report the bug in this case).
1461 The exit status is a "bit mask", each listed status is ORed when the error
1462 condition occurs to get the result.
1472 No compiler commands were found.
1476 Invalid arguments/options given to blhc.
1484 Missing hardening flags.
1488 Hardening wrapper detected, no tests performed.
1492 Invalid CMake version used. See B<I-invalid-cmake-used> under L</"BUILDD
1493 TAGS"> for a detailed explanation.
1499 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
1501 Thanks to to Bernhard R. Link E<lt>brlink@debian.orgE<gt> and Jaria Alto
1502 E<lt>jari.aalto@cante.netE<gt> for their valuable input and suggestions.
1504 =head1 LICENSE AND COPYRIGHT
1506 Copyright (C) 2012-2013 by Simon Ruderich
1508 This program is free software: you can redistribute it and/or modify
1509 it under the terms of the GNU General Public License as published by
1510 the Free Software Foundation, either version 3 of the License, or
1511 (at your option) any later version.
1513 This program is distributed in the hope that it will be useful,
1514 but WITHOUT ANY WARRANTY; without even the implied warranty of
1515 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1516 GNU General Public License for more details.
1518 You should have received a copy of the GNU General Public License
1519 along with this program. If not, see <http://www.gnu.org/licenses/>.
1523 L<hardening-check(1)>, L<dpkg-buildflags(1)>