3 # Build log hardening check, checks build logs for missing hardening flags.
5 # Copyright (C) 2012-2022 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 = '0.13';
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\+\+|gfortran|mpicc|mpicxx|mpifort)
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_prefix = qr/
42 [a-z0-9_]+-(?:linux-|kfreebsd-)?gnu(?:eabi|eabihf)?
44 my $cc_regex_full = qr/
45 (?:$cc_regex_full_prefix-)?
48 # Regex to check if a line contains a compiler command.
49 my $cc_regex_normal = qr/
52 # Regex to catch (GCC) compiler warnings.
53 my $warning_regex = qr/^(.+?):(\d+):\d+: warning: (.+?) \[(.+?)\]$/;
54 # Regex to catch libtool commands and not lines which show commands executed
55 # by libtool (e.g. libtool: link: ...).
56 my $libtool_regex = qr/\blibtool["']?\s.*--mode=/;
57 my $libtool_link_regex = qr/\blibtool: link: /;
59 # List of source file extensions which require preprocessing.
60 my @source_preprocess_compile_cpp = (
62 qw( cc cp cxx cpp CPP c++ C ),
66 my @source_preprocess_compile_fortran = (
68 qw( F FOR fpp FPP FTN F90 F95 F03 F08 ),
70 my @source_preprocess_compile = (
76 @source_preprocess_compile_cpp,
78 @source_preprocess_compile_fortran,
80 my @source_preprocess_no_compile = (
84 my @source_preprocess = (
85 @source_preprocess_compile,
86 @source_preprocess_no_compile,
88 # List of source file extensions which don't require preprocessing.
89 my @source_no_preprocess_compile_cpp = (
95 my @source_no_preprocess_compile_ada = (
101 my @source_no_preprocess_compile_fortran = (
103 qw( f for ftn f90 f95 f03 f08 ),
105 my @source_no_preprocess_compile = (
109 @source_no_preprocess_compile_cpp,
113 @source_no_preprocess_compile_fortran,
115 @source_no_preprocess_compile_ada,
117 my @source_no_preprocess_no_compile_ada = (
121 my @source_no_preprocess_no_compile = (
125 @source_no_preprocess_no_compile_ada,
127 my @source_no_preprocess = (
128 @source_no_preprocess_compile,
129 @source_no_preprocess_no_compile,
131 # List of header file extensions which require preprocessing.
132 my @header_preprocess = (
133 # C, C++, Objective-C, Objective-C++
136 qw( hh H hp hxx hpp HPP h++ tcc ),
140 # Normal object files.
142 # Libtool object files.
144 # Dynamic libraries. bzip2 uses .sho.
150 # Hashes for fast extensions lookup to check if a file falls in one of these
152 my %extensions_no_preprocess = map { $_ => 1 } (
153 # There's no @header_no_preprocess.
154 @source_no_preprocess,
156 my %extensions_preprocess = map { $_ => 1 } (
160 my %extensions_compile_link = map { $_ => 1 } (
162 @source_no_preprocess,
164 my %extensions_compile = map { $_ => 1 } (
165 @source_preprocess_compile,
166 @source_no_preprocess_compile,
168 my %extensions_no_compile = map { $_ => 1 } (
169 @source_preprocess_no_compile,
170 @source_no_preprocess_no_compile,
172 my %extensions_compile_cpp = map { $_ => 1 } (
173 @source_preprocess_compile_cpp,
174 @source_no_preprocess_compile_cpp,
176 my %extensions_ada = map { $_ => 1 } (
177 @source_no_preprocess_compile_ada,
178 @source_no_preprocess_no_compile_ada,
180 my %extensions_fortran = map { $_ => 1 } (
181 @source_no_preprocess_compile_fortran,
182 @source_preprocess_compile_fortran,
184 my %extensions_object = map { $_ => 1 } (
187 my %extension = map { $_ => 1 } (
188 @source_no_preprocess,
194 # Regexp to match file extensions.
195 my $file_extension_regex = qr/
197 \S+ # Filename without extension.
199 ([^\/\\.,;:\s]+)# File extension.
200 (?=\s|\\) # At end of word. Can't use \b because some files have non
201 # word characters at the end and because \b matches double
202 # extensions (like .cpp.o). Works always as all lines are
203 # terminated with "\n".
206 # Expected (hardening) flags. All flags are used as regexps (and compiled to
207 # real regexps below for better execution speed).
210 '-O(?:2|3)', # keep at index 1, search for @def_cflags_debug to change it
212 my @def_cflags_debug = (
213 # These flags indicate a debug build which disables checks for -O2.
217 my @def_cflags_format = (
218 '-Wformat(?:=2)?', # -Wformat=2 implies -Wformat, accept it too
219 '-Werror=format-security', # implies -Wformat-security
221 my @def_cflags_fortify = (
222 # fortify needs at least -O1, but -O2 is recommended anyway
224 my @def_cflags_stack = (
225 '-fstack-protector', # keep first, used by cflags_stack_broken()
226 '--param[= ]ssp-buffer-size=4',
228 my @def_cflags_stack_strong = (
229 '-fstack-protector-strong', # keep first, used by cflags_stack_broken()
231 my @def_cflags_stack_bad = (
232 # Blacklist all stack protector options for simplicity.
233 '-fno-stack-protector',
234 '-fno-stack-protector-all',
235 '-fno-stack-protector-strong',
237 my @def_cflags_pie = (
243 # @def_cxxflags_* is the same as @def_cflags_*.
244 my @def_cppflags = ();
245 my @def_cppflags_fortify = (
246 '-D_FORTIFY_SOURCE=[23]', # must be first, see cppflags_fortify_broken()
247 # If you add another flag fix hack below (search for "Hack to fix") and
248 # $def_cppflags_fortify[0].
250 my @def_cppflags_fortify_bad = (
251 # These flags may overwrite -D_FORTIFY_SOURCE=2.
253 '-D_FORTIFY_SOURCE=0',
254 '-D_FORTIFY_SOURCE=1',
256 my @def_ldflags = ();
257 my @def_ldflags_relro = (
260 my @def_ldflags_bindnow = (
263 my @def_ldflags_pie = (
267 my @def_ldflags_pic = (
272 # References to all flags checked by the flag checker.
276 \@def_cflags_fortify,
278 \@def_cflags_stack_strong,
279 \@def_cflags_stack_bad,
283 \@def_cppflags_fortify,
286 \@def_ldflags_bindnow,
289 # References to all used flags.
290 my @flag_refs_all = (
293 \@def_cppflags_fortify_bad,
296 # Renaming rules for the output so the regex parts are not visible. Also
297 # stores string values of flag regexps above, see compile_flag_regexp().
299 '-O(?:2|3)' => '-O2',
300 '-Wformat(?:=2)?' => '-Wformat',
301 '--param[= ]ssp-buffer-size=4' => '--param=ssp-buffer-size=4',
302 '-D_FORTIFY_SOURCE=[23]' => '-D_FORTIFY_SOURCE=2',
303 '-Wl,(?:-z,)?relro' => '-Wl,-z,relro',
304 '-Wl,(?:-z,)?now' => '-Wl,-z,now',
308 no_compiler_commands => 1 << 0,
309 # used by POD::Usage => 1 << 1,
310 non_verbose_build => 1 << 2,
311 flags_missing => 1 << 3,
312 hardening_wrapper => 1 << 4,
313 invalid_cmake => 1 << 5,
317 no_compiler_commands => 'I-no-compiler-commands',
318 non_verbose_build => 'W-compiler-flags-hidden',
319 flags_missing => 'W-dpkg-buildflags-missing',
320 hardening_wrapper => 'I-hardening-wrapper-used',
321 invalid_cmake => 'I-invalid-cmake-used',
324 # Statistics of missing flags and non-verbose build commands. Used for
328 preprocess_missing => 0,
330 compile_missing => 0,
332 compile_cpp_missing => 0,
336 commands_nonverbose => 0,
339 # Use colored (ANSI) output?
349 foreach my $delim (';', '&&', '||') {
352 push @x, Text::ParseWords::parse_line(qr/\Q$delim\E/, 1, $_);
358 # Ensure newline at the line end - necessary for
359 # correct parsing later.
366 my ($message, $missing_flags_ref, $flag_renames_ref, $line, $number) = @_;
368 # Get string value of qr//-escaped regexps and if requested rename them.
369 my @missing_flags = map {
370 $flag_renames_ref->{$_}
371 } @{$missing_flags_ref};
373 my $flags = join ' ', @missing_flags;
374 printf '%d:', $number if defined $number;
375 printf '%s (%s)%s %s',
376 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
381 sub error_non_verbose_build {
382 my ($line, $number) = @_;
384 printf '%d:', $number if defined $number;
386 error_color('NONVERBOSE BUILD', 'red'),
387 error_color(':', 'yellow'),
392 sub error_invalid_cmake {
396 error_color('INVALID CMAKE', 'red'),
397 error_color(':', 'yellow'),
402 sub error_hardening_wrapper {
404 error_color('HARDENING WRAPPER', 'red'),
405 error_color(':', 'yellow'),
406 'no checks possible, aborting';
411 my ($message, $color) = @_;
414 return Term::ANSIColor::colored($message, $color);
421 my ($line, @flags) = @_;
423 foreach my $flag (@flags) {
424 return 1 if $line =~ /$flag/;
430 my ($line, $missing_flags_ref, @flags) = @_;
432 my @missing_flags = ();
433 foreach my $flag (@flags) {
434 if (not $line =~ /$flag/) {
435 push @missing_flags, $flag;
439 return 1 if scalar @missing_flags == 0;
441 @{$missing_flags_ref} = @missing_flags;
444 # Check if any of \@bad_flags occurs after $good_flag. Doesn't check if
445 # $good_flag is present.
446 sub flag_overwritten {
447 my ($line, $good_flag, $bad_flags) = @_;
449 if (not any_flags_used($line, @{$bad_flags})) {
454 foreach my $flag (@{$bad_flags}) {
455 while ($line =~ /$flag/g) {
456 if ($bad_pos < $+[0]) {
462 while ($line =~ /$good_flag/g) {
465 if ($good_pos > $bad_pos) {
471 sub cppflags_fortify_broken {
472 my ($line, $missing_flags) = @_;
474 # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2!
475 my $fortify_source = $def_cppflags_fortify[0];
477 # Some build systems enable/disable fortify source multiple times, check
479 if (not flag_overwritten($line,
481 \@def_cppflags_fortify_bad)) {
484 push @{$missing_flags}, $fortify_source;
488 sub cflags_stack_broken {
489 my ($line, $missing_flags, $strong) = @_;
491 my $flag = $strong ? $def_cflags_stack_strong[0]
492 : $def_cflags_stack[0];
494 if (not flag_overwritten($line, $flag, \@def_cflags_stack_bad)) {
497 push @{$missing_flags}, $flag;
501 # Modifies $missing_flags_ref array.
502 sub pic_pie_conflict {
503 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
505 return 0 if not $pie;
506 return 0 if not any_flags_used($line, @def_ldflags_pic);
508 my %flags = map { $_ => 1 } @flags_pie;
510 # Remove all PIE flags from @missing_flags as they are not required with
513 not exists $flags{$_}
514 } @{$missing_flags_ref};
515 @{$missing_flags_ref} = @result;
517 # We got a conflict when no flags are left, thus only PIE flags were
518 # missing. If other flags were missing abort because the conflict is not
520 return scalar @result == 0;
523 sub is_non_verbose_build {
524 my ($line, $skip_ref, $input_ref, $line_offset, $line_count) = @_;
526 if ($line =~ /$libtool_regex/o) {
527 # libtool's --silent hides the real compiler flags.
528 if ($line =~ /\s--silent/) {
530 # If --silent is not present, skip this line as some compiler flags
531 # might be missing (e.g. -fPIE) which are handled correctly by libtool
532 # internally. libtool displays the real compiler command on the next
533 # line, so the flags are checked as usual.
540 if (not (index($line, 'checking if you want to see long compiling messages... no') == 0
541 or $line =~ /^\s*\[?(?:CC|CCLD|C\+\+|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
542 or $line =~ /^\s*[][\/0-9 ]*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/
543 or $line =~ /^\s*[Bb]uilding (?:program|shared library)\s+(.+?)$/
544 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
550 # C++ compiler setting.
551 return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/;
552 return 0 if $line =~ /^\s*C\+\+ Library: stdc\+\+$/;
553 # "Compiling" non binary files.
554 return 0 if $line =~ /^\s*Compiling \S+\.(?:py|pyx|el)['"]?\s*(?:\.\.\.|because it changed\.)?$/;
555 return 0 if $line =~ /^\s*[Cc]ompiling catalog \S+\.po\b/;
556 # "Compiling" with no file name.
557 if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) {
558 # $file_extension_regex may need spaces around the filename.
559 return 0 if not " $1 " =~ /$file_extension_regex/o;
564 # On the first pass we only check if this line is verbose or not.
565 return 1 if not defined $input_ref;
567 # Second pass, we have access to the next lines.
570 # CMake and other build systems print the non-verbose messages also when
571 # building verbose. If a compiler and the file name occurs in the next
572 # lines, treat it as verbose build.
574 # Get filename, we can't use the complete path as only parts of it are
575 # used in the real compiler command.
576 $file =~ m{/([^/\s]+)$};
579 for (my $i = 1; $i <= $line_count; $i++) {
580 my $next_line = $input_ref->[$line_offset + $i];
581 last unless defined $next_line;
583 if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) {
584 # Not a non-verbose line, but we still have to skip the
585 # current line as it doesn't contain any compiler commands.
595 # Remove @flags from $flag_refs_ref, uses $flag_renames_ref as reference.
597 my ($flag_refs_ref, $flag_renames_ref, @flags) = @_;
599 my %removes = map { $_ => 1 } @flags;
600 foreach my $flags (@{$flag_refs_ref}) {
602 # Flag found as string.
603 not exists $removes{$_}
604 # Flag found as string representation of regexp.
605 and (not defined $flag_renames_ref->{$_}
606 or not exists $removes{$flag_renames_ref->{$_}})
613 # Modifies $flag_renames_ref hash.
614 sub compile_flag_regexp {
615 my ($flag_renames_ref, @flags) = @_;
618 foreach my $flag (@flags) {
619 # Compile flag regexp for faster execution.
620 my $regex = qr/\s(['"]?)$flag\1(?:\s|\\)/;
622 # Store flag name in replacement string for correct flags in messages
623 # with qr//ed flag regexps.
624 $flag_renames_ref->{$regex}
625 = (exists $flag_renames_ref->{$flag})
626 ? $flag_renames_ref->{$flag}
629 push @result, $regex;
634 # Does any extension in @extensions exist in %{$extensions_ref}?
635 sub extension_found {
636 my ($extensions_ref, @extensions) = @_;
638 foreach my $extension (@extensions) {
639 if (exists $extensions_ref->{$extension}) {
649 # Parse command line arguments.
651 my $option_version = 0;
653 my $option_bindnow = 0;
654 my @option_ignore_arch = ();
655 my @option_ignore_flag = ();
656 my @option_ignore_arch_flag = ();
657 my @option_ignore_line = ();
658 my @option_ignore_arch_line = ();
660 my $option_arch = undef;
661 my $option_buildd = 0;
662 my $option_debian = 0;
664 my $option_line_numbers = 0;
665 if (not Getopt::Long::GetOptions(
666 'help|h|?' => \$option_help,
667 'version' => \$option_version,
669 'pie' => \$option_pie,
670 'bindnow' => \$option_bindnow,
671 'all' => \$option_all,
673 'ignore-arch=s' => \@option_ignore_arch,
674 'ignore-flag=s' => \@option_ignore_flag,
675 'ignore-arch-flag=s' => \@option_ignore_arch_flag,
676 'ignore-line=s' => \@option_ignore_line,
677 'ignore-arch-line=s' => \@option_ignore_arch_line,
679 'color' => \$option_color,
680 'arch=s' => \$option_arch,
681 'buildd' => \$option_buildd,
682 'debian' => \$option_debian,
683 'line-numbers' => \$option_line_numbers,
686 Pod::Usage::pod2usage(2);
690 Pod::Usage::pod2usage(1);
692 if ($option_version) {
694 blhc $VERSION Copyright (C) 2012-2022 Simon Ruderich
696 This program is free software: you can redistribute it and/or modify
697 it under the terms of the GNU General Public License as published by
698 the Free Software Foundation, either version 3 of the License, or
699 (at your option) any later version.
701 This program is distributed in the hope that it will be useful,
702 but WITHOUT ANY WARRANTY; without even the implied warranty of
703 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
704 GNU General Public License for more details.
706 You should have received a copy of the GNU General Public License
707 along with this program. If not, see <http://www.gnu.org/licenses/>.
713 if (scalar @ARGV == 0) {
715 Pod::Usage::pod2usage(2);
718 # Don't load Term::ANSIColor in buildd mode because Term::ANSIColor is not
719 # installed on Debian's buildds.
720 if (not $option_buildd) {
721 require Term::ANSIColor;
729 # Precompiled ignores for faster lookup.
730 my %option_ignore_arch_flag = ();
731 my %option_ignore_arch_line = ();
733 # Strip flags which should be ignored.
734 if (scalar @option_ignore_flag > 0) {
735 remove_flags(\@flag_refs, \%flag_renames, @option_ignore_flag);
737 # Same for arch specific ignore flags, but only prepare here.
738 if (scalar @option_ignore_arch_flag > 0) {
739 foreach my $ignore (@option_ignore_arch_flag) {
740 my ($ignore_arch, $ignore_flag) = split /:/, $ignore, 2;
742 if (not $ignore_arch or not $ignore_flag) {
743 printf STDERR 'Value "%s" invalid for option ignore-arch-flag '
744 . '("arch:flag" expected)' . "\n", $ignore;
746 Pod::Usage::pod2usage(2);
749 push @{$option_ignore_arch_flag{$ignore_arch}}, $ignore_flag;
753 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
755 foreach my $flags (@flag_refs_all) {
756 @{$flags} = compile_flag_regexp(\%flag_renames, @{$flags});
759 # Precompile ignore line regexps, also anchor at beginning and end of line.
760 # Additional entries are also extracted from the build log, see below.
761 foreach my $ignore (@option_ignore_line) {
762 $ignore = qr/^$ignore$/;
764 # Same for arch specific ignore lines.
765 if (scalar @option_ignore_arch_line > 0) {
766 foreach my $ignore (@option_ignore_arch_line) {
767 my ($ignore_arch, $ignore_line) = split /:/, $ignore, 2;
769 if (not $ignore_arch or not $ignore_line) {
770 printf STDERR 'Value "%s" invalid for option ignore-arch-line '
771 . '("arch:line" expected)' . "\n", $ignore;
773 Pod::Usage::pod2usage(2);
776 push @{$option_ignore_arch_line{$ignore_arch}}, qr/^$ignore_line$/;
784 foreach my $file (@ARGV) {
785 print "checking '$file'...\n" if scalar @ARGV > 1;
787 -f $file or die "No such file: $file";
789 open my $fh, '<', $file or die $!;
791 # Architecture of this file.
792 my $arch = $option_arch;
794 # Hardening options. Not all architectures support all hardening options.
795 my $harden_format = 1;
796 my $harden_fortify = 1;
797 my $harden_stack = 1;
798 my $harden_stack_strong = 1;
799 my $harden_relro = 1;
800 my $harden_bindnow = $option_bindnow; # defaults to 0
801 my $harden_pie = $option_pie; # defaults to 0
803 # Number of parallel jobs to prevent false positives when detecting
804 # non-verbose builds. As not all jobs declare the number of parallel jobs
805 # use a large enough default.
808 # Don't check for PIE flags if automatically applied by the compiler. Only
809 # used in buildd and Debian mode.
810 my $disable_harden_pie = 0;
811 if ($option_debian) {
812 $disable_harden_pie = 1;
816 while (my $line = <$fh>) {
819 # Detect architecture automatically unless overridden. For buildd logs
820 # only, doesn't use the dpkg-buildpackage header. Necessary to ignore
821 # build logs which aren't built (wrong architecture, build error,
824 if (index($line, 'Build Architecture: ') == 0) {
825 $arch = substr $line, 20, -1; # -1 to ignore '\n' at the end
826 # For old logs (sbuild << 0.63.0-1).
827 } elsif (index($line, 'Architecture: ') == 0) {
828 $arch = substr $line, 14, -1; # -1 to ignore '\n' at the end
832 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
833 # check for hardening flags in buildd mode if an older dpkg-dev is
834 # used. Default flags (-g -O2) are still checked.
836 # Packages which were built before 1.16.1 but used their own hardening
837 # flags are not checked.
839 # Strong stack protector is used since dpkg 1.17.11.
841 # Recent GCC versions automatically use PIE (only on supported
842 # architectures) and dpkg respects this properly since 1.18.15 and
843 # doesn't pass PIE flags manually.
845 and index($line, 'Toolchain package versions: ') == 0) {
846 require Dpkg::Version;
849 my $disable_strong = 1;
851 if ($line =~ /\bdpkg-dev_(\S+)/) {
852 if (Dpkg::Version::version_compare($1, '1.16.1') >= 0) {
855 if (Dpkg::Version::version_compare($1, '1.17.11') >= 0) {
858 if (Dpkg::Version::version_compare($1, '1.18.15') >= 0) {
859 $disable_harden_pie = 1;
871 if ($disable_strong) {
872 $harden_stack_strong = 0;
876 # The following two versions of CMake in Debian obeyed CPPFLAGS, but
877 # this was later dropped because upstream rejected the patch. Thus
878 # build logs with these versions will have fortify hardening flags
879 # enabled, even though they may be not correctly set and are missing
880 # when build with later CMake versions. Thanks to Aron Xu for letting
882 if (index($line, 'Package versions: ') == 0
883 and $line =~ /\bcmake_(\S+)/
884 and ($1 eq '2.8.7-1' or $1 eq '2.8.7-2')) {
885 if (not $option_buildd) {
886 error_invalid_cmake($1);
887 $exit |= $exit_code{invalid_cmake};
889 print "$buildd_tag{invalid_cmake}|$1|\n";
893 # Debian's build daemons use "Filtered Build-Depends:" (or just
894 # "Build-Depends:" in older versions) for the build dependencies, but
895 # pbuilder uses "Depends:"; support both.
896 if (index($line, 'Filtered Build-Depends: ') == 0
897 or index($line, 'Build-Depends: ') == 0
898 or index($line, 'Depends: ') == 0) {
899 # If hardening wrapper is used (wraps calls to gcc and adds
900 # hardening flags automatically) we can't perform any checks,
902 if ($line =~ /\bhardening-wrapper\b/) {
903 if (not $option_buildd) {
904 error_hardening_wrapper();
905 $exit |= $exit_code{hardening_wrapper};
907 print "$buildd_tag{hardening_wrapper}||\n";
913 # This flags is not always available, but if it is use it.
914 if ($line =~ /^DEB_BUILD_OPTIONS=.*\bparallel=(\d+)/) {
918 # We skip over unimportant lines at the beginning of the log to
919 # prevent false positives.
920 last if index($line, 'dpkg-buildpackage: ') == 0;
923 # Input lines, contain only the lines with compiler commands.
925 # Non-verbose lines in the input. Used to reduce calls to
926 # is_non_verbose_build() (which is quite slow) in the second loop when
927 # it's already clear if a line is non-verbose or not.
928 my @input_nonverbose = ();
930 my @input_number = ();
932 my $continuation = 0;
933 my $complete_line = undef;
935 while (my $line = <$fh>) {
938 # And stop at the end of the build log. Package details (reported by
939 # the buildd logs) are not important for us. This also prevents false
941 last if index($line, 'Build finished at ') == 0
942 and $line =~ /^Build finished at \d{8}-\d{4}$/;
944 if (not $continuation) {
948 # Detect architecture automatically unless overridden.
950 and index($line, 'dpkg-buildpackage: info: host architecture ') == 0) {
951 $arch = substr $line, 43, -1; # -1 to ignore '\n' at the end
952 # Older versions of dpkg-buildpackage
954 and index($line, 'dpkg-buildpackage: host architecture ') == 0) {
955 $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end
957 # Old buildd logs use e.g. "host architecture is alpha", remove
958 # the "is", otherwise debarch_to_debtriplet() will not detect the
960 if (index($arch, 'is ') == 0) {
961 $arch = substr $arch, 3;
965 # Permit dynamic excludes from within the build log to ignore false
966 # positives. Cannot use a separate config file as we often only have
967 # the build log itself.
968 if (index($line, 'blhc: ignore-line-regexp: ') == 0) {
969 my $ignore = substr $line, 26, -1; # -1 to ignore '\n' at the end
970 push @option_ignore_line, qr/^$ignore$/;
974 next if $line =~ /^\s*#/;
975 # Ignore compiler warnings for now.
976 next if $line =~ /$warning_regex/o;
978 if (not $option_buildd and index($line, "\033") != -1) { # \033 = esc
979 # Remove all ANSI color sequences which are sometimes used in
980 # non-verbose builds.
981 $line = Term::ANSIColor::colorstrip($line);
982 # Also strip '\0xf' (delete previous character), used by Elinks'
985 # And "ESC(B" which seems to be used on armhf and hurd (not sure
987 $line =~ s/\033\(B//g;
990 # Check if this line indicates a non verbose build.
992 $non_verbose |= is_non_verbose_build($line, \$skip);
995 # Treat each command as a single line so we don't ignore valid
996 # commands when handling false positives. split_line() is slow, only
997 # use it when necessary.
998 my @line = ($line !~ /(?:;|&&|\|\|)/)
1000 : split_line($line);
1001 foreach my $line (@line) {
1002 if ($continuation) {
1005 # Join lines, but leave the "\" in place so it's clear where
1006 # the original line break was.
1007 chomp $complete_line;
1008 $complete_line .= ' ' . $line;
1010 # Line continuation, line ends with "\".
1011 if ($line =~ /\\$/) {
1013 # Start line continuation.
1014 if (not defined $complete_line) {
1015 $complete_line = $line;
1020 # Use the complete line if a line continuation occurred.
1021 if (defined $complete_line) {
1022 $line = $complete_line;
1023 $complete_line = undef;
1027 # Strip (basic) environment variables for compiler detection. This
1028 # prevents false positives when environment variables contain
1029 # compiler binaries. Nested quotes, command substitution, etc. is
1034 [a-zA-Z_]+ # environment variable name
1037 [^\s"'\$`\\]+ # non-quoted string
1039 '[^"'\$`\\]*' # single-quoted string
1041 "[^"'\$`\\]*" # double-quoted string
1046 # Ignore lines with no compiler commands.
1047 next if not $non_verbose
1048 and not $noenv =~ /$cc_regex_normal/o;
1049 # Ignore lines with no filenames with extensions. May miss some
1050 # non-verbose builds (e.g. "gcc -o test" [sic!]), but shouldn't be
1051 # a problem as the log will most likely contain other non-verbose
1052 # commands which are detected.
1053 next if not $non_verbose
1054 and not $line =~ /$file_extension_regex/o;
1056 # Ignore false positives.
1058 # `./configure` output.
1059 next if not $non_verbose
1060 and $line =~ /^(?:checking|[Cc]onfigure:) /;
1061 next if $line =~ /^\s*(?:Host\s+)?(?:C(?:\+\+)?\s+)?
1062 [Cc]ompiler[\s.]*:?\s+
1064 next if $line =~ m{^\s*(?:-\s)?(?:HOST_)?(?:CC|CXX)
1065 \s*=\s*$cc_regex_full
1066 # optional compiler options, don't allow
1067 # "everything" here to prevent false negatives
1068 \s*(?:\s-\S+)*\s*$}xo;
1069 # `echo` is never a compiler command
1070 next if $line =~ /^\s*echo\s/;
1071 # Ignore calls to `make` because they can contain environment
1072 # variables which look like compiler commands, e.g. CC=).
1073 next if $line =~ /^\s*make\s/;
1074 # `moc-qt4`/`moc-qt5` contain '-I.../linux-g++' in their command
1075 # line (or similar for other architectures) which gets recognized
1076 # as a compiler line, but `moc-qt*` is only a preprocessor for Qt
1077 # C++ files. No hardening flags are relevant during this step,
1078 # thus ignore `moc-qt*` lines. The resulting files will be
1079 # compiled in a separate step (and therefore checked).
1080 next if $line =~ m{^\S+(?:/bin/moc(?:-qt[45])?|/lib/qt6/libexec/moc)
1082 -I\S+/mkspecs/[a-z]+-g\++(?:-64)?
1084 # Ignore false positives when the line contains only CC=gcc but no
1085 # other gcc command.
1086 if ($line =~ /(.*)CC=$cc_regex_full(.*)/o) {
1089 next if not $before =~ /$cc_regex_normal/o
1090 and not $after =~ /$cc_regex_normal/o;
1092 # Ignore false positives caused by gcc -v. It outputs a line
1093 # looking like a normal compiler line but which is sometimes
1094 # missing hardening flags, although the normal compiler line
1096 next if $line =~ m{^\s+/usr/lib/gcc/$cc_regex_full_prefix/
1097 [0-9.]+/cc1(?:plus)?}xo;
1098 # Ignore false positive with `rm` which may remove files which
1099 # look like a compiler executable thus causing the line to be
1100 # treated as a normal compiler line.
1101 next if $line =~ m{^\s*rm\s+};
1102 next if $line =~ m{^\s*dwz\s+};
1103 # Some build systems emit "gcc > file".
1104 next if $line =~ m{$cc_regex_normal\s*>\s*\S+}o;
1105 # Hex output may contain "cc".
1106 next if $line =~ m#(?:\b[0-9a-fA-F]{2,}\b\s*){5}#;
1107 # Meson build output
1108 next if $line =~ /^C\+\+ linker for the host machine: /;
1109 # Embedded `gcc -print-*` commands
1110 next if $line =~ /`$cc_regex_normal\s*[^`]*-print-\S+`/;
1111 # cmake checking for compiler flags without setting CPPFLAGS
1112 next if $line =~ m{^\s*/usr/(bin|lib)/(ccache/)?c\+\+ -dM -E -c /usr/share/cmake-\S+/Modules/CMakeCXXCompilerABI\.cpp};
1114 # Check if additional hardening options were used. Used to ensure
1115 # they are used for the complete build.
1116 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie,
1118 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
1121 push @input_nonverbose, $non_verbose;
1122 push @input_number, $number if $option_line_numbers;
1126 close $fh or die $!;
1128 # Ignore arch if requested.
1129 if (scalar @option_ignore_arch > 0 and $arch) {
1130 foreach my $ignore (@option_ignore_arch) {
1131 if ($arch eq $ignore) {
1132 print "ignoring architecture '$arch'\n";
1138 if (scalar @input == 0) {
1139 if (not $option_buildd) {
1140 print "No compiler commands!\n";
1141 $exit |= $exit_code{no_compiler_commands};
1143 print "$buildd_tag{no_compiler_commands}||\n";
1148 if ($option_buildd) {
1149 $statistics{commands} += scalar @input;
1152 # Option or auto detected.
1154 # The following was partially copied from dpkg-dev 1.21.13
1155 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, _add_build_flags()),
1156 # copyright Raphaël Hertzog <hertzog@debian.org>, Guillem Jover
1157 # <guillem@debian.org>, Kees Cook <kees@debian.org>, Canonical, Ltd.
1158 # licensed under GPL version 2 or later. Keep it in sync.
1162 # Recent dpkg versions use a quadruplet for arch. Support both.
1164 (undef, undef, $os, $cpu) = Dpkg::Arch::debarch_to_debtuple($arch);
1167 (undef, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch);
1170 my %builtin_pie_arch = map { $_ => 1 } qw(
1191 # Disable unsupported hardening options.
1192 if ($os !~ /^(?:linux|kfreebsd|knetbsd|hurd)$/
1193 or $cpu =~ /^(?:hppa|avr32)$/) {
1196 if ($cpu =~ /^(?:ia64|alpha|hppa|nios2)$/ or $arch eq 'arm') {
1198 $harden_stack_strong = 0;
1200 if ($cpu =~ /^(?:ia64|hppa|avr32)$/) {
1202 $harden_bindnow = 0;
1205 if ($disable_harden_pie and exists $builtin_pie_arch{$arch}) {
1211 my @cflags = @def_cflags;
1212 my @cxxflags = @def_cxxflags;
1213 my @cppflags = @def_cppflags;
1214 my @ldflags = @def_ldflags;
1215 # Check the specified hardening options, same order as dpkg-buildflags.
1217 @cflags = (@cflags, @def_cflags_pie);
1218 @cxxflags = (@cxxflags, @def_cflags_pie);
1219 @ldflags = (@ldflags, @def_ldflags_pie);
1221 if ($harden_stack_strong) {
1222 @cflags = (@cflags, @def_cflags_stack_strong);
1223 @cxxflags = (@cxxflags, @def_cflags_stack_strong);
1224 } elsif ($harden_stack) {
1225 @cflags = (@cflags, @def_cflags_stack);
1226 @cxxflags = (@cxxflags, @def_cflags_stack);
1228 if ($harden_fortify) {
1229 @cflags = (@cflags, @def_cflags_fortify);
1230 @cxxflags = (@cxxflags, @def_cflags_fortify);
1231 @cppflags = (@cppflags, @def_cppflags_fortify);
1233 if ($harden_format) {
1234 @cflags = (@cflags, @def_cflags_format);
1235 @cxxflags = (@cxxflags, @def_cflags_format);
1237 if ($harden_relro) {
1238 @ldflags = (@ldflags, @def_ldflags_relro);
1240 if ($harden_bindnow) {
1241 @ldflags = (@ldflags, @def_ldflags_bindnow);
1244 # Ada doesn't support format hardening flags, see #680117 for more
1245 # information. Same for fortran.
1247 my @cflags_noformat = grep {
1249 foreach my $flag (@def_cflags_format) {
1250 $ok = 0 if $_ eq $flag;
1255 # Hack to fix cppflags_fortify_broken() if --ignore-flag
1256 # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works
1257 # as long as @def_cppflags_fortify contains only one variable.
1258 if (scalar @def_cppflags_fortify == 0) {
1259 $harden_fortify = 0;
1262 # Ignore flags for this arch if requested.
1263 if ($arch and exists $option_ignore_arch_flag{$arch}) {
1264 my @local_flag_refs = (\@cflags, \@cxxflags, \@cppflags, \@ldflags);
1266 remove_flags(\@local_flag_refs,
1268 @{$option_ignore_arch_flag{$arch}});
1271 my @ignore_line = @option_ignore_line;
1272 # Ignore lines for this arch if requested.
1273 if ($arch and exists $option_ignore_arch_line{$arch}) {
1274 @ignore_line = (@ignore_line, @{$option_ignore_arch_line{$arch}});
1278 for (my $i = 0; $i < scalar @input; $i++) {
1279 my $line = $input[$i];
1281 # Ignore line if requested.
1282 foreach my $ignore (@ignore_line) {
1283 next LINE if $line =~ /$ignore/;
1287 if ($input_nonverbose[$i]
1288 and is_non_verbose_build($line, \$skip,
1289 \@input, $i, $parallel)) {
1290 if (not $option_buildd) {
1291 error_non_verbose_build($line, $input_number[$i]);
1292 $exit |= $exit_code{non_verbose_build};
1294 $statistics{commands_nonverbose}++;
1298 # Even if it's a verbose build, we might have to skip this line (see
1299 # is_non_verbose_build()).
1302 my $orig_line = $line;
1304 # Remove everything until and including the compiler command. Makes
1305 # checks easier and faster.
1306 $line =~ s/^.*?$cc_regex//o;
1307 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
1308 # the brace and similar characters at the line end.
1309 $line =~ s/['")]+$//;
1311 # Skip unnecessary tests when only preprocessing.
1312 my $flag_preprocess = 0;
1319 # Preprocess, compile, assemble.
1320 if ($line =~ /\s(-E|-S|-c)\b/) {
1322 $flag_preprocess = 1 if $1 eq '-E';
1323 $compile = 1 if $1 eq '-S' or $1 eq '-c';
1324 # Dependency generation for Makefiles. The other flags (-MF -MG -MP
1325 # -MT -MQ) are always used with -M/-MM.
1326 } elsif ($line =~ /\s(?:-M|-MM)\b/) {
1328 # Otherwise assume we are linking.
1333 # -MD/-MMD also cause dependency generation, but they don't imply -E!
1334 if ($line =~ /\s(?:-MD|-MMD)\b/) {
1336 $flag_preprocess = 0;
1339 # Dependency generation for Makefiles, no preprocessing or other flags
1341 next if $dependency;
1343 # Get all file extensions on this line.
1344 my @extensions = $line =~ /$file_extension_regex/go;
1345 # Ignore all unknown extensions to speedup the search below.
1346 @extensions = grep { exists $extension{$_} } @extensions;
1348 # These file types don't require preprocessing.
1349 if (extension_found(\%extensions_no_preprocess, @extensions)) {
1352 # These file types require preprocessing.
1353 if (extension_found(\%extensions_preprocess, @extensions)) {
1354 # Prevent false positives with "libtool: link: g++ -include test.h
1355 # .." compiler lines.
1356 if ($orig_line !~ /$libtool_link_regex/o) {
1361 if (not $flag_preprocess) {
1362 # If there are source files then it's compiling/linking in one
1363 # step and we must check both. We only check for source files
1364 # here, because header files cause too many false positives.
1365 if (extension_found(\%extensions_compile_link, @extensions)) {
1366 # Assembly files don't need CFLAGS.
1367 if (not extension_found(\%extensions_compile, @extensions)
1368 and extension_found(\%extensions_no_compile, @extensions)) {
1370 # But the rest does.
1374 # No compilable extensions found, either linking or compiling
1377 # If there are also no object files we are just compiling headers
1378 # (.h -> .h.gch). Don't check for linker flags in this case. Due
1379 # to our liberal checks for compiler lines, this also reduces the
1380 # number of false positives considerably.
1382 and not extension_found(\%extensions_object, @extensions)) {
1387 my $compile_cpp = 0;
1388 my $restore_cflags = 0;
1389 # Assume CXXFLAGS are required when a C++ file is specified in the
1392 and extension_found(\%extensions_compile_cpp, @extensions)) {
1395 # Ada needs special CFLAGS
1396 } elsif (extension_found(\%extensions_ada, @extensions)) {
1397 $restore_cflags = 1;
1398 $preprocess = 0; # Ada uses no CPPFLAGS
1399 @cflags_backup = @cflags;
1400 @cflags = @cflags_noformat;
1402 } elsif (extension_found(\%extensions_fortran, @extensions)) {
1403 $restore_cflags = 1;
1404 @cflags_backup = @cflags;
1405 @cflags = @cflags_noformat;
1408 if ($option_buildd) {
1409 $statistics{preprocess}++ if $preprocess;
1410 $statistics{compile}++ if $compile;
1411 $statistics{compile_cpp}++ if $compile_cpp;
1412 $statistics{link}++ if $link;
1415 # Check if there are flags indicating a debug build. If that's true,
1416 # skip the check for -O2. This prevents fortification, but that's fine
1417 # for a debug build.
1418 if (any_flags_used($line, @def_cflags_debug)) {
1419 remove_flags([\@cflags], \%flag_renames, $def_cflags[1]);
1420 remove_flags([\@cppflags], \%flag_renames, $def_cppflags_fortify[0]);
1423 # Check hardening flags.
1425 if ($compile and (not all_flags_used($line, \@missing, @cflags)
1426 or (($harden_stack or $harden_stack_strong)
1427 and cflags_stack_broken($line, \@missing,
1428 $harden_stack_strong)))
1429 # Libraries linked with -fPIC don't have to (and can't) be
1430 # linked with -fPIE as well. It's no error if only PIE flags
1432 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1433 # Assume dpkg-buildflags returns the correct flags.
1434 and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) {
1435 if (not $option_buildd) {
1436 error_flags('CFLAGS missing', \@missing, \%flag_renames,
1437 $input[$i], $input_number[$i]);
1438 $exit |= $exit_code{flags_missing};
1440 $statistics{compile_missing}++;
1442 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
1443 # Libraries linked with -fPIC don't have to (and can't) be
1444 # linked with -fPIE as well. It's no error if only PIE flags
1446 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1447 # Assume dpkg-buildflags returns the correct flags.
1448 and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) {
1449 if (not $option_buildd) {
1450 error_flags('CXXFLAGS missing', \@missing, \%flag_renames,
1451 $input[$i], $input_number[$i]);
1452 $exit |= $exit_code{flags_missing};
1454 $statistics{compile_cpp_missing}++;
1458 and (not all_flags_used($line, \@missing, @cppflags)
1459 # The fortify flag might be overwritten, detect that.
1461 and cppflags_fortify_broken($line, \@missing)))
1462 # Assume dpkg-buildflags returns the correct flags.
1463 and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) {
1464 if (not $option_buildd) {
1465 error_flags('CPPFLAGS missing', \@missing, \%flag_renames,
1466 $input[$i], $input_number[$i]);
1467 $exit |= $exit_code{flags_missing};
1469 $statistics{preprocess_missing}++;
1472 if ($link and not all_flags_used($line, \@missing, @ldflags)
1473 # Same here, -fPIC conflicts with -fPIE.
1474 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
1475 # Assume dpkg-buildflags returns the correct flags.
1476 and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) {
1477 if (not $option_buildd) {
1478 error_flags('LDFLAGS missing', \@missing, \%flag_renames,
1479 $input[$i], $input_number[$i]);
1480 $exit |= $exit_code{flags_missing};
1482 $statistics{link_missing}++;
1486 # Restore normal CFLAGS.
1487 if ($restore_cflags) {
1488 @cflags = @cflags_backup;
1493 # Print statistics for buildd mode, only output in this mode.
1494 if ($option_buildd) {
1497 if ($statistics{preprocess_missing}) {
1498 push @warning, sprintf 'CPPFLAGS %d (of %d)',
1499 $statistics{preprocess_missing},
1500 $statistics{preprocess};
1502 if ($statistics{compile_missing}) {
1503 push @warning, sprintf 'CFLAGS %d (of %d)',
1504 $statistics{compile_missing},
1505 $statistics{compile};
1507 if ($statistics{compile_cpp_missing}) {
1508 push @warning, sprintf 'CXXFLAGS %d (of %d)',
1509 $statistics{compile_cpp_missing},
1510 $statistics{compile_cpp};
1512 if ($statistics{link_missing}) {
1513 push @warning, sprintf 'LDFLAGS %d (of %d)',
1514 $statistics{link_missing},
1517 if (scalar @warning) {
1518 local $" = ', '; # array join string
1519 print "$buildd_tag{flags_missing}|@warning missing|\n";
1522 if ($statistics{commands_nonverbose}) {
1523 printf "$buildd_tag{non_verbose_build}|%d (of %d) hidden|\n",
1524 $statistics{commands_nonverbose},
1525 $statistics{commands},
1537 blhc - build log hardening check, checks build logs for missing hardening flags
1541 B<blhc> [I<options>] I<< <dpkg-buildpackage build log file>.. >>
1545 blhc is a small tool which checks build logs for missing hardening flags. It's
1546 licensed under the GPL 3 or later.
1548 It's designed to check build logs generated by Debian's dpkg-buildpackage (or
1549 tools using dpkg-buildpackage like pbuilder or sbuild (which is used for the
1550 official buildd build logs)) to help maintainers detect missing hardening
1551 flags in their packages.
1553 Only gcc is detected as compiler at the moment. If other compilers support
1554 hardening flags as well, please report them.
1556 If there's no output, no flags are missing and the build log is fine.
1558 See F<README> for details about performed checks, auto-detection and
1561 =head1 FALSE POSITIVES
1563 To suppress false positives you can embed the following string in the build
1566 blhc: ignore-line-regexp: REGEXP
1568 All lines fully matching REGEXP (see B<--ignore-line> for details) will be
1571 Please use this feature sparingly so that missing flags are not overlooked. If
1572 you find false positives which affect more packages please report a bug.
1574 To generate this string simply use echo in C<debian/rules>; make sure to use @
1575 to suppress the echo command itself as it could also trigger a false positive.
1576 If the build process takes a long time edit the C<.build> file in place and
1577 tweak the ignore string until B<blhc --all --debian package.build> no longer
1578 reports any false positives.
1586 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
1589 =item B<--arch> I<architecture>
1591 Set the specific architecture (e.g. amd64, armel, etc.), automatically
1592 disables hardening flags not available on this architecture. Is detected
1593 automatically if dpkg-buildpackage is used.
1597 Force check for all +bindnow hardening flags. By default it's auto detected.
1601 Special mode for buildds when automatically parsing log files. The following
1602 changes are in effect:
1608 Print tags instead of normal warnings, see L</"BUILDD TAGS"> for a list of
1613 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
1618 Don't require Term::ANSIColor.
1622 Return exit code 0, unless there was a error (-I, -W messages don't count as
1629 Apply Debian-specific settings. At the moment this only disables checking for
1630 PIE which is automatically applied by Debian's GCC and no longer requires a
1631 compiler command line argument.
1635 Use colored (ANSI) output for warning messages.
1637 =item B<--line-numbers>
1639 Display line numbers.
1641 =item B<--ignore-arch> I<arch>
1643 Ignore build logs from architectures matching I<arch>. I<arch> is a string.
1645 Used to prevent false positives. This option can be specified multiple times.
1647 =item B<--ignore-arch-flag> I<arch>:I<flag>
1649 Like B<--ignore-flag>, but only ignore flag on I<arch>.
1651 =item B<--ignore-arch-line> I<arch>:I<line>
1653 Like B<--ignore-line>, but only ignore line on I<arch>.
1655 =item B<--ignore-flag> I<flag>
1657 Don't print an error when the specific flag is missing in a compiler line.
1658 I<flag> is a string.
1660 Used to prevent false positives. This option can be specified multiple times.
1662 =item B<--ignore-line> I<regex>
1664 Ignore lines matching the given Perl regex. I<regex> is automatically anchored
1665 at the beginning and end of the line to prevent false negatives.
1667 B<NOTE>: Not the input lines are checked, but the lines which are displayed in
1668 warnings (which have line continuation resolved).
1670 Used to prevent false positives. This option can be specified multiple times.
1674 Force check for all +pie hardening flags. By default it's auto detected.
1676 =item B<-h -? --help>
1678 Print available options.
1682 Print version number and license.
1686 Auto detection for B<--pie> and B<--bindnow> only works if at least one
1687 command uses the required hardening flag (e.g. -fPIE). Then it's required for
1688 all other commands as well.
1692 Normal usage, parse a single log file.
1694 blhc path/to/log/file
1696 If there's no output, no flags are missing and the build log is fine.
1698 Parse multiple log files. The exit code is ORed over all files.
1700 blhc path/to/directory/with/log/files/*
1702 Don't treat missing C<-g> as error:
1704 blhc --ignore-flag -g path/to/log/file
1706 Don't treat missing C<-pie> on kfreebsd-amd64 as error:
1708 blhc --ignore-arch-flag kfreebsd-amd64:-pie path/to/log/file
1710 Ignore lines consisting exactly of C<./script gcc file> which would cause a
1713 blhc --ignore-line '\./script gcc file' path/to/log/file
1715 Ignore lines matching C<./script gcc file> somewhere in the line.
1717 blhc --ignore-line '.*\./script gcc file.*' path/to/log/file
1719 Use blhc with pbuilder.
1721 pbuilder path/to/package.dsc | tee path/log/file
1722 blhc path/to/file || echo flags missing
1724 Assume this build log was created on a Debian system and thus don't warn about
1725 missing PIE flags if the current architecture injects them automatically (this
1726 is enabled in buildd mode per default). C<--arch> is necessary if the build
1727 log contains no architecture information as written by dpkg-buildpackage.
1729 blhc --debian --all --arch=amd64 path/to/log/file
1733 The following tags are used in I<--buildd> mode. In braces the additional data
1738 =item B<I-hardening-wrapper-used>
1740 The package uses hardening-wrapper which intercepts calls to gcc and adds
1741 hardening flags. The build log doesn't contain any hardening flags and thus
1742 can't be checked by blhc.
1744 =item B<W-compiler-flags-hidden> (summary of hidden lines)
1746 Build log contains lines which hide the real compiler flags. For example:
1753 Most of the time either C<export V=1> or C<export verbose=1> in
1754 F<debian/rules> fixes builds with hidden compiler flags. Sometimes C<.SILENT>
1755 in a F<Makefile> must be removed. And as last resort the F<Makefile> must be
1756 patched to remove the C<@>s hiding the real compiler commands.
1758 =item B<W-dpkg-buildflags-missing> (summary of missing flags)
1760 CPPFLAGS, CFLAGS, CXXFLAGS, LDFLAGS missing.
1762 =item B<I-invalid-cmake-used> (version)
1764 By default CMake ignores CPPFLAGS thus missing those hardening flags. Debian
1765 patched CMake in versions 2.8.7-1 and 2.8.7-2 to respect CPPFLAGS, but this
1766 patch was rejected by upstream and later reverted in Debian. Thus those two
1767 versions show correct usage of CPPFLAGS even if the package doesn't correctly
1768 handle them (for example by passing them to CFLAGS). To prevent false
1769 negatives just blacklist those two versions.
1771 =item B<I-no-compiler-commands>
1773 No compiler commands were detected. Either the log contains none or they were
1774 not correctly detected by blhc (please report the bug in this case).
1780 The exit status is a "bit mask", each listed status is ORed when the error
1781 condition occurs to get the result.
1791 No compiler commands were found.
1795 Invalid arguments/options given to blhc.
1803 Missing hardening flags.
1807 Hardening wrapper detected, no tests performed.
1811 Invalid CMake version used. See B<I-invalid-cmake-used> under L</"BUILDD
1812 TAGS"> for a detailed explanation.
1818 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
1820 Thanks to to Bernhard R. Link E<lt>brlink@debian.orgE<gt> and Jaria Alto
1821 E<lt>jari.aalto@cante.netE<gt> for their valuable input and suggestions.
1823 =head1 LICENSE AND COPYRIGHT
1825 Copyright (C) 2012-2022 by Simon Ruderich
1827 This program is free software: you can redistribute it and/or modify
1828 it under the terms of the GNU General Public License as published by
1829 the Free Software Foundation, either version 3 of the License, or
1830 (at your option) any later version.
1832 This program is distributed in the hope that it will be useful,
1833 but WITHOUT ANY WARRANTY; without even the implied warranty of
1834 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1835 GNU General Public License for more details.
1837 You should have received a copy of the GNU General Public License
1838 along with this program. If not, see <http://www.gnu.org/licenses/>.
1842 L<hardening-check(1)>, L<dpkg-buildflags(1)>