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 = (
185 '-Wformat(?:=2)?', # -Wformat=2 implies -Wformat, accept it too
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 '-Wformat(?:=2)?' => '-Wformat',
255 '--param[= ]ssp-buffer-size=4' => '--param=ssp-buffer-size=4',
256 '-Wl,(?:-z,)?relro' => '-Wl,-z,relro',
257 '-Wl,(?:-z,)?now' => '-Wl,-z,now',
261 no_compiler_commands => 1 << 0,
262 # used by POD::Usage => 1 << 1,
263 non_verbose_build => 1 << 2,
264 flags_missing => 1 << 3,
265 hardening_wrapper => 1 << 4,
266 invalid_cmake => 1 << 5,
270 no_compiler_commands => 'I-no-compiler-commands',
271 non_verbose_build => 'W-compiler-flags-hidden',
272 flags_missing => 'W-dpkg-buildflags-missing',
273 hardening_wrapper => 'I-hardening-wrapper-used',
274 invalid_cmake => 'I-invalid-cmake-used',
277 # Statistics of missing flags and non-verbose build commands. Used for
281 preprocess_missing => 0,
283 compile_missing => 0,
285 compile_cpp_missing => 0,
289 commands_nonverbose => 0,
292 # Use colored (ANSI) output?
298 # Only works for single-level arrays with no undef values. Thanks to perlfaq4.
300 my ($first_ref, $second_ref) = @_;
302 return 0 if scalar @{$first_ref} != scalar @{$second_ref};
304 my $length = scalar @{$first_ref};
305 for (my $i = 0; $i < $length; $i++) {
306 return 0 if $first_ref->[$i] ne $second_ref->[$i];
313 my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_;
315 # Get string value of qr//-escaped regexps and if requested rename them.
316 my @missing_flags = map {
317 $flag_renames_ref->{$_}
318 } @{$missing_flags_ref};
320 my $flags = join ' ', @missing_flags;
321 printf '%s (%s)%s %s',
322 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
327 sub error_non_verbose_build {
331 error_color('NONVERBOSE BUILD', 'red'),
332 error_color(':', 'yellow'),
337 sub error_invalid_cmake {
341 error_color('INVALID CMAKE', 'red'),
342 error_color(':', 'yellow'),
347 sub error_hardening_wrapper {
349 error_color('HARDENING WRAPPER', 'red'),
350 error_color(':', 'yellow'),
351 'no checks possible, aborting';
356 my ($message, $color) = @_;
359 return Term::ANSIColor::colored($message, $color);
366 my ($line, @flags) = @_;
368 foreach my $flag (@flags) {
369 return 1 if $line =~ /$flag/;
375 my ($line, $missing_flags_ref, @flags) = @_;
377 my @missing_flags = ();
378 foreach my $flag (@flags) {
379 if (not $line =~ /$flag/) {
380 push @missing_flags, $flag;
384 return 1 if scalar @missing_flags == 0;
386 @{$missing_flags_ref} = @missing_flags;
390 sub cppflags_fortify_broken {
391 my ($line, $missing_flags) = @_;
393 # This doesn't take the position into account, but is a simple solution.
394 # And if the build system tries to force -D_FORTIFY_SOURCE=0/1, something
397 if (any_flags_used($line, @def_cppflags_fortify_bad)) {
398 # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2!
399 push @{$missing_flags}, $def_cppflags_fortify[0];
406 # Modifies $missing_flags_ref array.
407 sub pic_pie_conflict {
408 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
410 return 0 if not $pie;
411 return 0 if not any_flags_used($line, @def_ldflags_pic);
413 my %flags = map { $_ => 1 } @flags_pie;
415 # Remove all PIE flags from @missing_flags as they are not required with
418 not exists $flags{$_}
419 } @{$missing_flags_ref};
420 @{$missing_flags_ref} = @result;
422 # We got a conflict when no flags are left, thus only PIE flags were
423 # missing. If other flags were missing abort because the conflict is not
425 return scalar @result == 0;
428 sub is_non_verbose_build {
429 my ($line, $next_line, $skip_ref) = @_;
431 if (not (index($line, 'checking if you want to see long compiling messages... no') == 0
432 or $line =~ /^\s*\[?(?:CC|CCLD|C\+\+|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
433 or $line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/
434 or $line =~ /^\s*[Bb]uilding (?:program|shared library)\s+(.+?)$/
435 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
441 # C++ compiler setting.
442 return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/;
443 # "Compiling" with no file name.
444 if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) {
445 # $file_extension_regex may need spaces around the filename.
446 return 0 if not " $1 " =~ /$file_extension_regex/o;
451 # On the first pass we only check if this line is verbose or not.
452 return 1 if not defined $next_line;
454 # Second pass, we have access to the next line.
457 # CMake and other build systems print the non-verbose messages also when
458 # building verbose. If a compiler and the file name occurs in the next
459 # line, treat it as verbose build.
461 # Get filename, we can't use the complete path as only parts of it are
462 # used in the real compiler command.
463 $file =~ m{/([^/\s]+)$};
466 if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) {
467 # Not a non-verbose line, but we still have to skip the current line
468 # as it doesn't contain any compiler commands.
478 my ($flag_refs_ref, $flag_renames_ref, @flags) = @_;
480 my %removes = map { $_ => 1 } @flags;
481 foreach my $flags (@{$flag_refs_ref}) {
483 # Flag found as string.
484 not exists $removes{$_}
485 # Flag found as string representation of regexp.
486 and (not defined $flag_renames_ref->{$_}
487 or not exists $removes{$flag_renames_ref->{$_}})
494 sub compile_flag_regexp {
495 my ($flag_renames_ref, @flags) = @_;
498 foreach my $flag (@flags) {
499 # Store flag name in replacement string for correct flags in messages
500 # with qr//ed flag regexps.
501 $flag_renames_ref->{qr/\s$flag(?:\s|\\)/}
502 = (exists $flag_renames_ref->{$flag})
503 ? $flag_renames_ref->{$flag}
506 # Compile flag regexp for faster execution.
507 push @result, qr/\s$flag(?:\s|\\)/;
512 sub extension_found {
513 my ($extensions_ref, @extensions) = @_;
516 foreach my $extension (@extensions) {
517 if (exists $extensions_ref->{$extension}) {
528 # Parse command line arguments.
530 my $option_version = 0;
532 my $option_bindnow = 0;
533 my @option_ignore_arch = ();
534 my @option_ignore_flag = ();
535 my @option_ignore_arch_flag = ();
536 my @option_ignore_line = ();
537 my @option_ignore_arch_line = ();
539 my $option_arch = undef;
540 my $option_buildd = 0;
542 if (not Getopt::Long::GetOptions(
543 'help|h|?' => \$option_help,
544 'version' => \$option_version,
546 'pie' => \$option_pie,
547 'bindnow' => \$option_bindnow,
548 'all' => \$option_all,
550 'ignore-arch=s' => \@option_ignore_arch,
551 'ignore-flag=s' => \@option_ignore_flag,
552 'ignore-arch-flag=s' => \@option_ignore_arch_flag,
553 'ignore-line=s' => \@option_ignore_line,
554 'ignore-arch-line=s' => \@option_ignore_arch_line,
556 'color' => \$option_color,
557 'arch=s' => \$option_arch,
558 'buildd' => \$option_buildd,
561 Pod::Usage::pod2usage(2);
565 Pod::Usage::pod2usage(1);
567 if ($option_version) {
568 print "blhc $VERSION Copyright (C) 2012 Simon Ruderich
570 This program is free software: you can redistribute it and/or modify
571 it under the terms of the GNU General Public License as published by
572 the Free Software Foundation, either version 3 of the License, or
573 (at your option) any later version.
575 This program is distributed in the hope that it will be useful,
576 but WITHOUT ANY WARRANTY; without even the implied warranty of
577 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
578 GNU General Public License for more details.
580 You should have received a copy of the GNU General Public License
581 along with this program. If not, see <http://www.gnu.org/licenses/>.
587 if (scalar @ARGV == 0) {
589 Pod::Usage::pod2usage(2);
592 # Don't load Term::ANSIColor in buildd mode because Term::ANSIColor is not
593 # installed on Debian's buildds.
594 if (not $option_buildd) {
595 require Term::ANSIColor;
603 # Precompiled ignores for faster lookup.
604 my %option_ignore_arch_flag = ();
605 my %option_ignore_arch_line = ();
607 # Strip flags which should be ignored.
608 if (scalar @option_ignore_flag > 0) {
609 remove_flags(\@flag_refs, \%flag_renames, @option_ignore_flag);
611 # Same for arch specific ignore flags, but only prepare here.
612 if (scalar @option_ignore_arch_flag > 0) {
613 foreach my $ignore (@option_ignore_arch_flag) {
614 my ($ignore_arch, $ignore_flag) = split /:/, $ignore, 2;
616 if (not $ignore_arch or not $ignore_flag) {
617 printf STDERR 'Value "%s" invalid for option ignore-arch-flag '
618 . '("arch:flag" expected)' . "\n", $ignore;
620 Pod::Usage::pod2usage(2);
623 push @{$option_ignore_arch_flag{$ignore_arch}}, $ignore_flag;
627 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
629 foreach my $flags (@flag_refs_all) {
630 @{$flags} = compile_flag_regexp(\%flag_renames, @{$flags});
633 # Precompile ignore line regexps, also anchor at beginning and end of line.
634 foreach my $ignore (@option_ignore_line) {
635 $ignore = qr/^$ignore$/;
637 # Same for arch specific ignore lines.
638 if (scalar @option_ignore_arch_line > 0) {
639 foreach my $ignore (@option_ignore_arch_line) {
640 my ($ignore_arch, $ignore_line) = split /:/, $ignore, 2;
642 if (not $ignore_arch or not $ignore_line) {
643 printf STDERR 'Value "%s" invalid for option ignore-arch-line '
644 . '("arch:line" expected)' . "\n", $ignore;
646 Pod::Usage::pod2usage(2);
649 push @{$option_ignore_arch_line{$ignore_arch}}, qr/^$ignore_line$/;
657 foreach my $file (@ARGV) {
658 print "checking '$file'...\n" if scalar @ARGV > 1;
660 -f $file or die "No such file: $file";
662 open my $fh, '<', $file or die $!;
664 # Architecture of this file.
665 my $arch = $option_arch;
667 # Hardening options. Not all architectures support all hardening options.
668 my $harden_format = 1;
669 my $harden_fortify = 1;
670 my $harden_stack = 1;
671 my $harden_relro = 1;
672 my $harden_bindnow = $option_bindnow; # defaults to 0
673 my $harden_pie = $option_pie; # defaults to 0
675 # Does this build log use ada? Ada also uses gcc as compiler but uses
676 # different CFLAGS. But only perform ada checks if an ada compiler used
677 # for performance reasons.
680 while (my $line = <$fh>) {
681 # Detect architecture automatically unless overridden. For buildd logs
682 # only, doesn't use the dpkg-buildpackage header. Necessary to ignore
683 # build logs which aren't built (wrong architecture, build error,
685 if (not $arch and index($line, 'Architecture: ') == 0) {
686 $arch = substr $line, 14, -1; # -1 to ignore '\n' at the end
689 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
690 # check for hardening flags in buildd mode if an older dpkg-dev is
691 # used. Default flags (-g -O2) are still checked.
693 # Packages which were built before 1.16.1 but used their own hardening
694 # flags are not checked.
696 and index($line, 'Toolchain package versions: ') == 0) {
697 require Dpkg::Version;
698 if (not $line =~ /\bdpkg-dev_(\S+)/
699 or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
709 # The following two versions of CMake in Debian obeyed CPPFLAGS, but
710 # this was later dropped because upstream rejected the patch. Thus
711 # build logs with these versions will have fortify hardening flags
712 # enabled, even though they may be not correctly set and are missing
713 # when build with later CMake versions. Thanks to Aron Xu for letting
715 if (index($line, 'Package versions: ') == 0
716 and $line =~ /\bcmake_(\S+)/
717 and ($1 eq '2.8.7-1' or $1 eq '2.8.7-2')) {
718 if (not $option_buildd) {
719 error_invalid_cmake($1);
720 $exit |= $exit_code{invalid_cmake};
722 print "$buildd_tag{invalid_cmake}|$1|\n";
726 # Debian's build daemons use Build-Depends: for the build
727 # dependencies, but pbuilder just uses Depends:; support both.
728 if (index($line, 'Build-Depends: ') == 0
729 or index($line, 'Depends: ') == 0) {
730 # If hardening wrapper is used (wraps calls to gcc and adds
731 # hardening flags automatically) we can't perform any checks,
733 if ($line =~ /\bhardening-wrapper\b/) {
734 if (not $option_buildd) {
735 error_hardening_wrapper();
736 $exit |= $exit_code{hardening_wrapper};
738 print "$buildd_tag{hardening_wrapper}||\n";
744 if ($line =~ /\bgnat\b/) {
749 # We skip over unimportant lines at the beginning of the log to
750 # prevent false positives.
751 last if index($line, 'dpkg-buildpackage: ') == 0;
754 # Input lines, contain only the lines with compiler commands.
756 # Non-verbose lines in the input. Used to reduce calls to
757 # is_non_verbose_build() (which is quite slow) in the second loop when
758 # it's already clear if a line is non-verbose or not.
759 my @input_nonverbose = ();
761 my $continuation = 0;
762 my $complete_line = undef;
763 while (my $line = <$fh>) {
764 # And stop at the end of the build log. Package details (reported by
765 # the buildd logs) are not important for us. This also prevents false
767 last if index($line, 'Build finished at ') == 0
768 and $line =~ /^Build finished at \d{8}-\d{4}$/;
770 # Detect architecture automatically unless overridden.
772 and index($line, 'dpkg-buildpackage: host architecture ') == 0) {
773 $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end
775 # Old buildd logs use e.g. "host architecture is alpha", remove
776 # the "is", otherwise debarch_to_debtriplet() will not detect the
778 if (index($arch, 'is ') == 0) {
779 $arch = substr $arch, 3;
783 # Ignore compiler warnings for now.
784 next if $line =~ /$warning_regex/o;
786 if (not $option_buildd and index($line, "\033") != -1) { # \033 = esc
787 # Remove all ANSI color sequences which are sometimes used in
788 # non-verbose builds.
789 $line = Term::ANSIColor::colorstrip($line);
790 # Also strip '\0xf' (delete previous character), used by Elinks'
793 # And "ESC(B" which seems to be used on armhf and hurd (not sure
795 $line =~ s/\033\(B//g;
798 # Check if this line indicates a non verbose build.
799 my $non_verbose = is_non_verbose_build($line);
801 # One line may contain multiple commands (";"). Treat each one as
802 # single line. parse_line() is slow, only use it when necessary.
803 my @line = (index($line, ';') == -1)
806 # Ensure newline at the line end - necessary for
807 # correct parsing later.
810 } Text::ParseWords::parse_line(';', 1, $line);
811 foreach my $line (@line) {
815 # Join lines, but leave the "\" in place so it's clear where
816 # the original line break was.
817 chomp $complete_line;
818 $complete_line .= ' ' . $line;
820 # Line continuation, line ends with "\".
821 if ($line =~ /\\$/) {
823 # Start line continuation.
824 if (not defined $complete_line) {
825 $complete_line = $line;
830 # Use the complete line if a line continuation occurred.
831 if (defined $complete_line) {
832 $line = $complete_line;
833 $complete_line = undef;
836 # Ignore lines with no compiler commands.
837 next if not $non_verbose
838 and not $line =~ /$cc_regex_normal/o;
839 # Ignore lines with no filenames with extensions. May miss some
840 # non-verbose builds (e.g. "gcc -o test" [sic!]), but shouldn't be
841 # a problem as the log will most likely contain other non-verbose
842 # commands which are detected.
843 next if not $non_verbose
844 and not $line =~ /$file_extension_regex/o;
846 # Ignore false positives.
848 # `./configure` output.
849 next if not $non_verbose
850 and $line =~ /^(?:checking|[Cc]onfigure:) /;
851 next if $line =~ /^\s*(?:Host\s+)?(?:C(?:\+\+)?\s+)?
852 [Cc]ompiler[\s.]*:?\s+
854 next if $line =~ /^\s*(?:- )?(?:HOST_)?(?:CC|CXX)\s*=\s*$cc_regex_full\s*$/o;
855 # `moc-qt4`, contains '-I/usr/share/qt4/mkspecs/linux-g++' (or
856 # similar for other architectures) which gets recognized as a
857 # compiler line. Ignore it.
858 next if $line =~ m{^/usr/bin/moc-qt4
860 -I/usr/share/qt4/mkspecs/[a-z]+-g\++(?:-64)?
862 # Ignore false positives when the line contains only CC=gcc but no
864 if ($line =~ /(.*)CC=$cc_regex_full(.*)/o) {
867 next if not $before =~ /$cc_regex_normal/o
868 and not $after =~ /$cc_regex_normal/o;
871 # Check if additional hardening options were used. Used to ensure
872 # they are used for the complete build.
873 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie,
875 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
878 push @input_nonverbose, $non_verbose;
884 # Ignore arch if requested.
885 if (scalar @option_ignore_arch > 0 and $arch) {
886 foreach my $ignore (@option_ignore_arch) {
887 if ($arch eq $ignore) {
888 print "ignoring architecture '$arch'\n";
894 if (scalar @input == 0) {
895 if (not $option_buildd) {
896 print "No compiler commands!\n";
897 $exit |= $exit_code{no_compiler_commands};
899 print "$buildd_tag{no_compiler_commands}||\n";
904 if ($option_buildd) {
905 $statistics{commands} += scalar @input;
908 # Option or auto detected.
910 # The following was partially copied from dpkg-dev 1.16.4.3
911 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
912 # copyright Raphaël Hertzog <hertzog@debian.org>, Kees Cook
913 # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
914 # later. Keep it in sync.
917 my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch);
919 # Disable unsupported hardening options.
920 if ($cpu =~ /^(?:ia64|alpha|mips|mipsel|hppa)$/ or $arch eq 'arm') {
923 if ($cpu =~ /^(?:ia64|hppa|avr32)$/) {
930 my @cflags = @def_cflags;
931 my @cxxflags = @def_cxxflags;
932 my @cppflags = @def_cppflags;
933 my @ldflags = @def_ldflags;
934 # Check the specified hardening options, same order as dpkg-buildflags.
936 @cflags = (@cflags, @def_cflags_pie);
937 @cxxflags = (@cxxflags, @def_cflags_pie);
938 @ldflags = (@ldflags, @def_ldflags_pie);
941 @cflags = (@cflags, @def_cflags_stack);
942 @cxxflags = (@cxxflags, @def_cflags_stack);
944 if ($harden_fortify) {
945 @cflags = (@cflags, @def_cflags_fortify);
946 @cxxflags = (@cxxflags, @def_cflags_fortify);
947 @cppflags = (@cppflags, @def_cppflags_fortify);
949 if ($harden_format) {
950 @cflags = (@cflags, @def_cflags_format);
951 @cxxflags = (@cxxflags, @def_cflags_format);
954 @ldflags = (@ldflags, @def_ldflags_relro);
956 if ($harden_bindnow) {
957 @ldflags = (@ldflags, @def_ldflags_bindnow);
960 # Stores normal CFLAGS when @cflags_ada are temporarily used.
963 my @cflags_ada = @cflags;
964 # Ada doesn't support format hardening flags, see #680117 for more
965 # information. Filter them out if ada is used.
966 if ($ada and $harden_format) {
969 foreach my $flag (@def_cflags_format) {
970 $ok = 0 if $_ eq $flag;
976 # Hack to fix cppflags_fortify_broken() if --ignore-flag
977 # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works
978 # as long as @def_cppflags_fortify contains only one variable.
979 if (scalar @def_cppflags_fortify == 0) {
983 # Ignore flags for this arch if requested.
984 if ($arch and exists $option_ignore_arch_flag{$arch}) {
985 my @local_flag_refs = (\@cflags, \@cxxflags, \@cppflags, \@ldflags);
987 remove_flags(\@local_flag_refs,
989 @{$option_ignore_arch_flag{$arch}});
992 my @ignore_line = @option_ignore_line;
993 # Ignore lines for this arch if requested.
994 if ($arch and exists $option_ignore_arch_line{$arch}) {
995 @ignore_line = (@ignore_line, @{$option_ignore_arch_line{$arch}});
999 for (my $i = 0; $i < scalar @input; $i++) {
1000 my $line = $input[$i];
1002 # Ignore line if requested.
1003 foreach my $ignore (@ignore_line) {
1004 next LINE if $line =~ /$ignore/;
1008 if ($input_nonverbose[$i]
1009 and is_non_verbose_build($line, $input[$i + 1], \$skip)) {
1010 if (not $option_buildd) {
1011 error_non_verbose_build($line);
1012 $exit |= $exit_code{non_verbose_build};
1014 $statistics{commands_nonverbose}++;
1018 # Even if it's a verbose build, we might have to skip this line.
1021 # Remove everything until and including the compiler command. Makes
1022 # checks easier and faster.
1023 $line =~ s/^.*?$cc_regex//o;
1024 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
1025 # the brace and similar characters at the line end.
1026 $line =~ s/['")]+$//;
1028 # Skip unnecessary tests when only preprocessing.
1029 my $flag_preprocess = 0;
1036 # Preprocess, compile, assemble.
1037 if ($line =~ /\s(-E|-S|-c)\b/) {
1039 $flag_preprocess = 1 if $1 eq '-E';
1040 $compile = 1 if $1 eq '-S' or $1 eq '-c';
1041 # Dependency generation for Makefiles. The other flags (-MF -MG -MP
1042 # -MT -MQ) are always used with -M/-MM.
1043 } elsif ($line =~ /\s(?:-M|-MM)\b/) {
1045 # Otherwise assume we are linking.
1050 # -MD/-MMD also cause dependency generation, but they don't imply -E!
1051 if ($line =~ /\s(?:-MD|-MMD)\b/) {
1053 $flag_preprocess = 0;
1056 # Dependency generation for Makefiles, no preprocessing or other flags
1058 next if $dependency;
1060 # Get all file extensions on this line.
1061 my @extensions = $line =~ /$file_extension_regex/go;
1062 # Ignore all unknown extensions to speedup the search below.
1063 @extensions = grep { exists $extension{$_} } @extensions;
1065 # These file types don't require preprocessing.
1066 if (extension_found(\%extensions_no_preprocess, @extensions)) {
1069 # These file types require preprocessing.
1070 if (extension_found(\%extensions_preprocess, @extensions)) {
1074 if (not $flag_preprocess) {
1075 # If there are source files then it's compiling/linking in one
1076 # step and we must check both. We only check for source files
1077 # here, because header files cause too many false positives.
1078 if (extension_found(\%extensions_compile_link, @extensions)) {
1079 # Assembly files don't need CFLAGS.
1080 if (not extension_found(\%extensions_compile, @extensions)
1081 and extension_found(\%extensions_no_compile, @extensions)) {
1083 # But the rest does.
1087 # No compilable extensions found, either linking or compiling
1090 # If there are also no object files we are just compiling headers
1091 # (.h -> .h.gch). Don't check for linker flags in this case. Due
1092 # to our liberal checks for compiler lines, this also reduces the
1093 # number of false positives considerably.
1095 and not extension_found(\%extensions_object, @extensions)) {
1100 my $compile_cpp = 0;
1101 my $compile_ada = 0;
1102 # Assume CXXFLAGS are required when a C++ file is specified in the
1105 and extension_found(\%extensions_compile_cpp, @extensions)) {
1108 # Ada needs special CFLAGS, use them if only ada files are compiled.
1111 and array_equal(\@extensions,
1112 \@source_no_preprocess_compile_ada)) {
1114 @cflags_backup = @cflags;
1115 @cflags = @cflags_ada;
1118 if ($option_buildd) {
1119 $statistics{preprocess}++ if $preprocess;
1120 $statistics{compile}++ if $compile;
1121 $statistics{compile_cpp}++ if $compile_cpp;
1122 $statistics{link}++ if $link;
1125 # Check hardening flags.
1127 if ($compile and not all_flags_used($line, \@missing, @cflags)
1128 # Libraries linked with -fPIC don't have to (and can't) be
1129 # linked with -fPIE as well. It's no error if only PIE flags
1131 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1132 # Assume dpkg-buildflags returns the correct flags.
1133 and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) {
1134 if (not $option_buildd) {
1135 error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1136 $exit |= $exit_code{flags_missing};
1138 $statistics{compile_missing}++;
1140 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
1141 # Libraries linked with -fPIC don't have to (and can't) be
1142 # linked with -fPIE as well. It's no error if only PIE flags
1144 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1145 # Assume dpkg-buildflags returns the correct flags.
1146 and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) {
1147 if (not $option_buildd) {
1148 error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1149 $exit |= $exit_code{flags_missing};
1151 $statistics{compile_cpp_missing}++;
1155 and (not all_flags_used($line, \@missing, @cppflags)
1156 # The fortify flag might be overwritten, detect that.
1158 and cppflags_fortify_broken($line, \@missing)))
1159 # Assume dpkg-buildflags returns the correct flags.
1160 and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) {
1161 if (not $option_buildd) {
1162 error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1163 $exit |= $exit_code{flags_missing};
1165 $statistics{preprocess_missing}++;
1168 if ($link and not all_flags_used($line, \@missing, @ldflags)
1169 # Same here, -fPIC conflicts with -fPIE.
1170 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
1171 # Assume dpkg-buildflags returns the correct flags.
1172 and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) {
1173 if (not $option_buildd) {
1174 error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1175 $exit |= $exit_code{flags_missing};
1177 $statistics{link_missing}++;
1181 # Restore normal CFLAGS.
1183 @cflags = @cflags_backup;
1188 # Print statistics for buildd mode, only output in this mode.
1189 if ($option_buildd) {
1192 if ($statistics{preprocess_missing}) {
1193 push @warning, sprintf 'CPPFLAGS %d (of %d)',
1194 $statistics{preprocess_missing},
1195 $statistics{preprocess};
1197 if ($statistics{compile_missing}) {
1198 push @warning, sprintf 'CFLAGS %d (of %d)',
1199 $statistics{compile_missing},
1200 $statistics{compile};
1202 if ($statistics{compile_cpp_missing}) {
1203 push @warning, sprintf 'CXXFLAGS %d (of %d)',
1204 $statistics{compile_cpp_missing},
1205 $statistics{compile_cpp};
1207 if ($statistics{link_missing}) {
1208 push @warning, sprintf 'LDFLAGS %d (of %d)',
1209 $statistics{link_missing},
1212 if (scalar @warning) {
1213 local $" = ', '; # array join string
1214 print "$buildd_tag{flags_missing}|@warning missing|\n";
1217 if ($statistics{commands_nonverbose}) {
1218 printf "$buildd_tag{non_verbose_build}|%d (of %d) hidden|\n",
1219 $statistics{commands_nonverbose},
1220 $statistics{commands},
1232 blhc - build log hardening check, checks build logs for missing hardening flags
1236 B<blhc> [I<options>] I<< <dpkg-buildpackage build log file>.. >>
1240 blhc is a small tool which checks build logs for missing hardening flags. It's
1241 licensed under the GPL 3 or later.
1243 It's designed to check build logs generated by Debian's dpkg-buildpackage (or
1244 tools using dpkg-buildpackage like pbuilder or the official buildd build logs)
1245 to help maintainers detect missing hardening flags in their packages.
1247 Only gcc is detected as compiler at the moment. If other compilers support
1248 hardening flags as well, please report them.
1250 If there's no output, no flags are missing and the build log is fine.
1258 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
1261 =item B<--arch> I<architecture>
1263 Set the specific architecture (e.g. amd64, armel, etc.), automatically
1264 disables hardening flags not available on this architecture. Is detected
1265 automatically if dpkg-buildpackage is used.
1269 Force check for all +bindnow hardening flags. By default it's auto detected.
1273 Special mode for buildds when automatically parsing log files. The following
1274 changes are in effect:
1280 Print tags instead of normal warnings, see L</"BUILDD TAGS"> for a list of
1285 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
1290 Don't require Term::ANSIColor.
1294 Return exit code 0, unless there was a error (-I, -W messages don't count as
1301 Use colored (ANSI) output for warning messages.
1303 =item B<--ignore-arch> I<arch>
1305 Ignore build logs from architectures matching I<arch>. I<arch> is a string.
1307 Used to prevent false positives. This option can be specified multiple times.
1309 =item B<--ignore-arch-flag> I<arch>:I<flag>
1311 Like B<--ignore-flag>, but only ignore flag on I<arch>.
1313 =item B<--ignore-arch-line> I<arch>:I<line>
1315 Like B<--ignore-line>, but only ignore line on I<arch>.
1317 =item B<--ignore-flag> I<flag>
1319 Don't print an error when the specific flag is missing in a compiler line.
1320 I<flag> is a string.
1322 Used to prevent false positives. This option can be specified multiple times.
1324 =item B<--ignore-line> I<regex>
1326 Ignore lines matching the given Perl regex. I<regex> is automatically anchored
1327 at the beginning and end of the line to prevent false negatives.
1329 B<NOTE>: Not the input lines are checked, but the lines which are displayed in
1330 warnings (which have line continuation resolved).
1332 Used to prevent false positives. This option can be specified multiple times.
1336 Force check for all +pie hardening flags. By default it's auto detected.
1338 =item B<-h -? --help>
1340 Print available options.
1344 Print version number and license.
1348 Auto detection for B<--pie> and B<--bindnow> only works if at least one
1349 command uses the required hardening flag (e.g. -fPIE). Then it's required for
1350 all other commands as well.
1354 Normal usage, parse a single log file.
1356 blhc path/to/log/file
1358 If there's no output, no flags are missing and the build log is fine.
1360 Parse multiple log files. The exit code is ORed over all files.
1362 blhc path/to/directory/with/log/files/*
1364 Don't treat missing C<-g> as error:
1366 blhc --ignore-flag -g path/to/log/file
1368 Don't treat missing C<-pie> on kfreebsd-amd64 as error:
1370 blhc --ignore-arch-flag kfreebsd-amd64:-pie path/to/log/file
1372 Ignore lines consisting exactly of C<./script gcc file> which would cause a
1375 blhc --ignore-line '\./script gcc file' path/to/log/file
1377 Ignore lines matching C<./script gcc file> somewhere in the line.
1379 blhc --ignore-line '.*\./script gcc file.*' path/to/log/file
1381 Use blhc with pbuilder.
1383 pbuilder path/to/package.dsc | tee path/log/file
1384 blhc path/to/file || echo flags missing
1388 The following tags are used in I<--buildd> mode. In braces the additional data
1393 =item B<I-hardening-wrapper-used>
1395 The package uses hardening-wrapper which intercepts calls to gcc and adds
1396 hardening flags. The build log doesn't contain any hardening flags and thus
1397 can't be checked by blhc.
1399 =item B<W-compiler-flags-hidden> (summary of hidden lines)
1401 Build log contains lines which hide the real compiler flags. For example:
1408 Most of the time either C<export V=1> or C<export verbose=1> in
1409 F<debian/rules> fixes builds with hidden compiler flags. Sometimes C<.SILENT>
1410 in a F<Makefile> must be removed. And as last resort the F<Makefile> must be
1411 patched to remove the C<@>s hiding the real compiler commands.
1413 =item B<W-dpkg-buildflags-missing> (summary of missing flags)
1415 CPPFLAGS, CFLAGS, CXXFLAGS, LDFLAGS missing.
1417 =item B<I-invalid-cmake-used> (version)
1419 By default CMake ignores CPPFLAGS thus missing those hardening flags. Debian
1420 patched CMake in versions 2.8.7-1 and 2.8.7-2 to respect CPPFLAGS, but this
1421 patch was rejected by upstream and later reverted in Debian. Thus those two
1422 versions show correct usage of CPPFLAGS even if the package doesn't correctly
1423 handle them (for example by passing them to CFLAGS). To prevent false
1424 negatives just blacklist those two versions.
1426 =item B<I-no-compiler-commands>
1428 No compiler commands were detected. Either the log contains none or they were
1429 not correctly detected by blhc (please report the bug in this case).
1435 The exit status is a "bit mask", each listed status is ORed when the error
1436 condition occurs to get the result.
1446 No compiler commands were found.
1450 Invalid arguments/options given to blhc.
1458 Missing hardening flags.
1462 Hardening wrapper detected, no tests performed.
1466 Invalid CMake version used. See B<I-invalid-cmake-used> under L</"BUILDD
1467 TAGS"> for a detailed explanation.
1473 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
1475 Thanks to to Bernhard R. Link E<lt>brlink@debian.orgE<gt> and Jaria Alto
1476 E<lt>jari.aalto@cante.netE<gt> for their valuable input and suggestions.
1478 =head1 LICENSE AND COPYRIGHT
1480 Copyright (C) 2012 by Simon Ruderich
1482 This program is free software: you can redistribute it and/or modify
1483 it under the terms of the GNU General Public License as published by
1484 the Free Software Foundation, either version 3 of the License, or
1485 (at your option) any later version.
1487 This program is distributed in the hope that it will be useful,
1488 but WITHOUT ANY WARRANTY; without even the implied warranty of
1489 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1490 GNU General Public License for more details.
1492 You should have received a copy of the GNU General Public License
1493 along with this program. If not, see <http://www.gnu.org/licenses/>.
1497 L<hardening-check(1)>, L<dpkg-buildflags(1)>