3 # Build log hardening check, checks build logs for missing hardening flags.
5 # Copyright (C) 2012 Simon Ruderich
7 # This program is free software: you can redistribute it and/or modify
8 # it under the terms of the GNU General Public License as published by
9 # the Free Software Foundation, either version 3 of the License, or
10 # (at your option) any later version.
12 # This program is distributed in the hope that it will be useful,
13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 # GNU General Public License for more details.
17 # You should have received a copy of the GNU General Public License
18 # along with this program. If not, see <http://www.gnu.org/licenses/>.
25 use Text::ParseWords ();
27 our $VERSION = '0.03';
32 # Regex to catch compiler commands.
34 (?<!\s-) # ignore options, e.g. "-c++" [sic!] (used by swig)
35 (?<!\.) # ignore file names, e.g. "test.gcc"
36 (?:cc|gcc|g\+\+|c\+\+)
37 (?:-[\d.]+)? # version suffix, e.g. "gcc-4.6"
39 # Full regex which matches the complete compiler name. Used in a few places to
40 # prevent false negatives.
41 my $cc_regex_full = qr/
42 (?:[a-z0-9_]+-(?:linux-|kfreebsd-)?gnu(?:eabi|eabihf)?-)?
45 # Regex to check if a line contains a compiler command.
46 my $cc_regex_normal = qr/
49 # Regex to catch (GCC) compiler warnings.
50 my $warning_regex = qr/^(.+?):(\d+):\d+: warning: (.+?) \[(.+?)\]$/;
52 # List of source file extensions which require preprocessing.
53 my @source_preprocess_compile_cpp = (
55 qw( cc cp cxx cpp CPP c++ C ),
59 my @source_preprocess_compile = (
65 @source_preprocess_compile_cpp,
67 qw( F FOR fpp FPP FTN F90 F95 F03 F08 ),
69 my @source_preprocess_no_compile = (
73 my @source_preprocess = (
74 @source_preprocess_compile,
75 @source_preprocess_no_compile,
77 # List of source file extensions which don't require preprocessing.
78 my @source_no_preprocess_compile_cpp = (
84 my @source_no_preprocess_compile_ada = (
87 # If you add another file, fix use of @source_no_preprocess_compile_ada
88 # below (search for $compile_ada).
90 my @source_no_preprocess_compile = (
94 @source_no_preprocess_compile_cpp,
98 qw( f for ftn f90 f95 f03 f08 ),
100 @source_no_preprocess_compile_ada,
102 my @source_no_preprocess_no_compile = (
108 my @source_no_preprocess = (
109 @source_no_preprocess_compile,
110 @source_no_preprocess_no_compile,
112 # List of header file extensions which require preprocessing.
113 my @header_preprocess = (
114 # C, C++, Objective-C, Objective-C++
117 qw( hh H hp hxx hpp HPP h++ tcc ),
121 # Normal object files.
123 # Libtool object files.
125 # Dynamic libraries. bzip2 uses .sho.
131 # Hashes for fast extensions lookup to check if a file falls in one of these
133 my %extensions_no_preprocess = map { $_ => 1 } (
134 # There's no @header_no_preprocess.
135 @source_no_preprocess,
137 my %extensions_preprocess = map { $_ => 1 } (
141 my %extensions_compile_link = map { $_ => 1 } (
143 @source_no_preprocess,
145 my %extensions_compile = map { $_ => 1 } (
146 @source_preprocess_compile,
147 @source_no_preprocess_compile,
149 my %extensions_no_compile = map { $_ => 1 } (
150 @source_preprocess_no_compile,
151 @source_no_preprocess_no_compile,
153 my %extensions_compile_cpp = map { $_ => 1 } (
154 @source_preprocess_compile_cpp,
155 @source_no_preprocess_compile_cpp,
157 my %extensions_object = map { $_ => 1 } (
160 my %extension = map { $_ => 1 } (
161 @source_no_preprocess,
167 # Regexp to match file extensions.
168 my $file_extension_regex = qr/
170 \S+ # Filename without extension.
172 ([^\/\\.,;:\s]+)# File extension.
173 (?=\s|\\) # At end of word. Can't use \b because some files have non
174 # word characters at the end and because \b matches double
175 # extensions (like .cpp.o). Works always as all lines are
176 # terminated with "\n".
179 # Expected (hardening) flags. All flags are used as regexps.
184 my @def_cflags_format = (
186 '-Werror=format-security', # implies -Wformat-security
188 my @def_cflags_fortify = (
189 # fortify needs at least -O1, but -O2 is recommended anyway
191 my @def_cflags_stack = (
193 '--param=ssp-buffer-size=4',
195 my @def_cflags_pie = (
201 # @def_cxxflags_* is the same as @def_cflags_*.
202 my @def_cppflags = ();
203 my @def_cppflags_fortify = (
204 '-D_FORTIFY_SOURCE=2', # must be first, see cppflags_fortify_broken()
205 # If you add another flag fix hack below (search for "Hack to fix").
207 my @def_cppflags_fortify_bad = (
208 # These flags may overwrite -D_FORTIFY_SOURCE=2.
210 '-D_FORTIFY_SOURCE=0',
211 '-D_FORTIFY_SOURCE=1',
213 my @def_ldflags = ();
214 my @def_ldflags_relro = (
217 my @def_ldflags_bindnow = (
220 my @def_ldflags_pie = (
224 my @def_ldflags_pic = (
229 # References to all flags checked by the flag checker.
233 \@def_cflags_fortify,
238 \@def_cppflags_fortify,
241 \@def_ldflags_bindnow,
244 # References to all used flags.
245 my @flag_refs_all = (
247 \@def_cppflags_fortify_bad,
250 # Renaming rules for the output so the regex parts are not visible. Also
251 # stores string values of flag regexps above, see compile_flag_regexp().
253 '-O(?:2|3)' => '-O2',
254 '-Wl,(?:-z,)?relro' => '-Wl,-z,relro',
255 '-Wl,(?:-z,)?now' => '-Wl,-z,now',
259 no_compiler_commands => 1 << 0,
260 # used by POD::Usage => 1 << 1,
261 non_verbose_build => 1 << 2,
262 flags_missing => 1 << 3,
263 hardening_wrapper => 1 << 4,
264 invalid_cmake => 1 << 5,
268 no_compiler_commands => 'I-no-compiler-commands',
269 non_verbose_build => 'W-compiler-flags-hidden',
270 flags_missing => 'W-dpkg-buildflags-missing',
271 hardening_wrapper => 'I-hardening-wrapper-used',
272 invalid_cmake => 'I-invalid-cmake-used',
275 # Statistics of missing flags and non-verbose build commands. Used for
279 preprocess_missing => 0,
281 compile_missing => 0,
283 compile_cpp_missing => 0,
287 commands_nonverbose => 0,
290 # Use colored (ANSI) output?
296 # Only works for single-level arrays with no undef values. Thanks to perlfaq4.
298 my ($first_ref, $second_ref) = @_;
300 return 0 if scalar @{$first_ref} != scalar @{$second_ref};
302 my $length = scalar @{$first_ref};
303 for (my $i = 0; $i < $length; $i++) {
304 return 0 if $first_ref->[$i] ne $second_ref->[$i];
311 my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_;
313 # Get string value of qr//-escaped regexps and if requested rename them.
314 my @missing_flags = map {
315 $flag_renames_ref->{$_}
316 } @{$missing_flags_ref};
318 my $flags = join ' ', @missing_flags;
319 printf '%s (%s)%s %s',
320 error_color($message, 'red'), $flags, error_color(':', 'yellow'),
323 sub error_non_verbose_build {
327 error_color('NONVERBOSE BUILD', 'red'),
328 error_color(':', 'yellow'),
331 sub error_invalid_cmake {
335 error_color('INVALID CMAKE', 'red'),
336 error_color(':', 'yellow'),
339 sub error_hardening_wrapper {
341 error_color('HARDENING WRAPPER', 'red'),
342 error_color(':', 'yellow'),
343 'no checks possible, aborting';
346 my ($message, $color) = @_;
349 return Term::ANSIColor::colored($message, $color);
356 my ($line, @flags) = @_;
358 foreach my $flag (@flags) {
359 return 1 if $line =~ /$flag/;
365 my ($line, $missing_flags_ref, @flags) = @_;
367 my @missing_flags = ();
368 foreach my $flag (@flags) {
369 if (not $line =~ /$flag/) {
370 push @missing_flags, $flag;
374 return 1 if scalar @missing_flags == 0;
376 @{$missing_flags_ref} = @missing_flags;
380 sub cppflags_fortify_broken {
381 my ($line, $missing_flags) = @_;
383 # This doesn't take the position into account, but is a simple solution.
384 # And if the build system tries to force -D_FORTIFY_SOURCE=0/1, something
387 if (any_flags_used($line, @def_cppflags_fortify_bad)) {
388 # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2!
389 push @{$missing_flags}, $def_cppflags_fortify[0];
396 # Modifies $missing_flags_ref array.
397 sub pic_pie_conflict {
398 my ($line, $pie, $missing_flags_ref, @flags_pie) = @_;
400 return 0 if not $pie;
401 return 0 if not any_flags_used($line, @def_ldflags_pic);
403 my %flags = map { $_ => 1 } @flags_pie;
405 # Remove all PIE flags from @missing_flags as they are not required with
408 not exists $flags{$_}
409 } @{$missing_flags_ref};
410 @{$missing_flags_ref} = @result;
412 # We got a conflict when no flags are left, thus only PIE flags were
413 # missing. If other flags were missing abort because the conflict is not
415 return scalar @result == 0;
418 sub is_non_verbose_build {
419 my ($line, $next_line, $skip_ref) = @_;
421 if (not (index($line, 'checking if you want to see long compiling messages... no') == 0
422 or $line =~ /^\s*\[?(?:CC|CCLD|C\+\+|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
423 or $line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/
424 or $line =~ /^\s*[Bb]uilding (?:program|shared library)\s+(.+?)$/
425 or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
431 # C++ compiler setting.
432 return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/;
433 # "Compiling" with no file name.
434 if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) {
435 # $file_extension_regex may need spaces around the filename.
436 return 0 if not " $1 " =~ /$file_extension_regex/o;
441 # On the first pass we only check if this line is verbose or not.
442 return 1 if not defined $next_line;
444 # Second pass, we have access to the next line.
447 # CMake and other build systems print the non-verbose messages also when
448 # building verbose. If a compiler and the file name occurs in the next
449 # line, treat it as verbose build.
451 # Get filename, we can't use the complete path as only parts of it are
452 # used in the real compiler command.
453 $file =~ m{/([^/\s]+)$};
456 if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) {
457 # Not a non-verbose line, but we still have to skip the current line
458 # as it doesn't contain any compiler commands.
468 my ($flag_refs_ref, $flag_renames_ref, @flags) = @_;
470 my %removes = map { $_ => 1 } @flags;
471 foreach my $flags (@{$flag_refs_ref}) {
473 # Flag found as string.
474 not exists $removes{$_}
475 # Flag found as string representation of regexp.
476 and (not defined $flag_renames_ref->{$_}
477 or not exists $removes{$flag_renames_ref->{$_}})
482 sub compile_flag_regexp {
483 my ($flag_renames_ref, @flags) = @_;
486 foreach my $flag (@flags) {
487 # Store flag name in replacement string for correct flags in messages
488 # with qr//ed flag regexps.
489 $flag_renames_ref->{qr/\s$flag(?:\s|\\)/}
490 = (exists $flag_renames_ref->{$flag})
491 ? $flag_renames_ref->{$flag}
494 # Compile flag regexp for faster execution.
495 push @result, qr/\s$flag(?:\s|\\)/;
500 sub extension_found {
501 my ($extensions_ref, @extensions) = @_;
504 foreach my $extension (@extensions) {
505 if (exists $extensions_ref->{$extension}) {
516 # Parse command line arguments.
518 my $option_version = 0;
520 my $option_bindnow = 0;
521 my @option_ignore_arch = ();
522 my @option_ignore_flag = ();
523 my @option_ignore_arch_flag = ();
524 my @option_ignore_line = ();
525 my @option_ignore_arch_line = ();
527 my $option_arch = undef;
528 my $option_buildd = 0;
530 if (not Getopt::Long::GetOptions(
531 'help|h|?' => \$option_help,
532 'version' => \$option_version,
534 'pie' => \$option_pie,
535 'bindnow' => \$option_bindnow,
536 'all' => \$option_all,
538 'ignore-arch=s' => \@option_ignore_arch,
539 'ignore-flag=s' => \@option_ignore_flag,
540 'ignore-arch-flag=s' => \@option_ignore_arch_flag,
541 'ignore-line=s' => \@option_ignore_line,
542 'ignore-arch-line=s' => \@option_ignore_arch_line,
544 'color' => \$option_color,
545 'arch=s' => \$option_arch,
546 'buildd' => \$option_buildd,
549 Pod::Usage::pod2usage(2);
553 Pod::Usage::pod2usage(1);
555 if ($option_version) {
556 print "blhc $VERSION Copyright (C) 2012 Simon Ruderich
558 This program is free software: you can redistribute it and/or modify
559 it under the terms of the GNU General Public License as published by
560 the Free Software Foundation, either version 3 of the License, or
561 (at your option) any later version.
563 This program is distributed in the hope that it will be useful,
564 but WITHOUT ANY WARRANTY; without even the implied warranty of
565 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
566 GNU General Public License for more details.
568 You should have received a copy of the GNU General Public License
569 along with this program. If not, see <http://www.gnu.org/licenses/>.
575 if (scalar @ARGV == 0) {
577 Pod::Usage::pod2usage(2);
580 # Don't load Term::ANSIColor in buildd mode because Term::ANSIColor is not
581 # installed on Debian's buildds.
582 if (not $option_buildd) {
583 require Term::ANSIColor;
591 # Precompiled ignores for faster lookup.
592 my %option_ignore_arch_flag = ();
593 my %option_ignore_arch_line = ();
595 # Strip flags which should be ignored.
596 if (scalar @option_ignore_flag > 0) {
597 remove_flags(\@flag_refs, \%flag_renames, @option_ignore_flag);
599 # Same for arch specific ignore flags, but only prepare here.
600 if (scalar @option_ignore_arch_flag > 0) {
601 foreach my $ignore (@option_ignore_arch_flag) {
602 my ($ignore_arch, $ignore_flag) = split /:/, $ignore, 2;
604 if (not $ignore_arch or not $ignore_flag) {
605 printf STDERR 'Value "%s" invalid for option ignore-arch-flag '
606 . '("arch:flag" expected)' . "\n", $ignore;
608 Pod::Usage::pod2usage(2);
611 push @{$option_ignore_arch_flag{$ignore_arch}}, $ignore_flag;
615 # Precompile all flag regexps. any_flags_used(), all_flags_used() get a lot
617 foreach my $flags (@flag_refs_all) {
618 @{$flags} = compile_flag_regexp(\%flag_renames, @{$flags});
621 # Precompile ignore line regexps, also anchor at beginning and end of line.
622 foreach my $ignore (@option_ignore_line) {
623 $ignore = qr/^$ignore$/;
625 # Same for arch specific ignore lines.
626 if (scalar @option_ignore_arch_line > 0) {
627 foreach my $ignore (@option_ignore_arch_line) {
628 my ($ignore_arch, $ignore_line) = split /:/, $ignore, 2;
630 if (not $ignore_arch or not $ignore_line) {
631 printf STDERR 'Value "%s" invalid for option ignore-arch-line '
632 . '("arch:line" expected)' . "\n", $ignore;
634 Pod::Usage::pod2usage(2);
637 push @{$option_ignore_arch_line{$ignore_arch}}, qr/^$ignore_line$/;
645 foreach my $file (@ARGV) {
646 print "checking '$file'...\n" if scalar @ARGV > 1;
648 -f $file or die "No such file: $file";
650 open my $fh, '<', $file or die $!;
652 # Architecture of this file.
653 my $arch = $option_arch;
655 # Hardening options. Not all architectures support all hardening options.
656 my $harden_format = 1;
657 my $harden_fortify = 1;
658 my $harden_stack = 1;
659 my $harden_relro = 1;
660 my $harden_bindnow = $option_bindnow; # defaults to 0
661 my $harden_pie = $option_pie; # defaults to 0
663 # Does this build log use ada? Ada also uses gcc as compiler but uses
664 # different CFLAGS. But only perform ada checks if an ada compiler used
665 # for performance reasons.
668 while (my $line = <$fh>) {
669 # Detect architecture automatically unless overridden. For buildd logs
670 # only, doesn't use the dpkg-buildpackage header. Necessary to ignore
671 # build logs which aren't built (wrong architecture, build error,
673 if (not $arch and index($line, 'Architecture: ') == 0) {
674 $arch = substr $line, 14, -1; # -1 to ignore '\n' at the end
677 # dpkg-buildflags only provides hardening flags since 1.16.1, don't
678 # check for hardening flags in buildd mode if an older dpkg-dev is
679 # used. Default flags (-g -O2) are still checked.
681 # Packages which were built before 1.16.1 but used their own hardening
682 # flags are not checked.
684 and index($line, 'Toolchain package versions: ') == 0) {
685 require Dpkg::Version;
686 if (not $line =~ /\bdpkg-dev_(\S+)/
687 or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
697 # The following two versions of CMake in Debian obeyed CPPFLAGS, but
698 # this was later dropped because upstream rejected the patch. Thus
699 # build logs with these versions will have fortify hardening flags
700 # enabled, even though they may be not correctly set and are missing
701 # when build with later CMake versions. Thanks to Aron Xu for letting
703 if (index($line, 'Package versions: ') == 0
704 and $line =~ /\bcmake_(\S+)/
705 and ($1 eq '2.8.7-1' or $1 eq '2.8.7-2')) {
706 if (not $option_buildd) {
707 error_invalid_cmake($1);
708 $exit |= $exit_code{invalid_cmake};
710 print "$buildd_tag{invalid_cmake}|$1|\n";
714 if (index($line, 'Build-Depends: ') == 0) {
715 # If hardening wrapper is used (wraps calls to gcc and adds
716 # hardening flags automatically) we can't perform any checks,
718 if ($line =~ /\bhardening-wrapper\b/) {
719 if (not $option_buildd) {
720 error_hardening_wrapper();
721 $exit |= $exit_code{hardening_wrapper};
723 print "$buildd_tag{hardening_wrapper}||\n";
729 if ($line =~ /\bgnat\b/) {
734 # We skip over unimportant lines at the beginning of the log to
735 # prevent false positives.
736 last if index($line, 'dpkg-buildpackage: ') == 0;
739 # Input lines, contain only the lines with compiler commands.
741 # Non-verbose lines in the input. Used to reduce calls to
742 # is_non_verbose_build() (which is quite slow) in the second loop when
743 # it's already clear if a line is non-verbose or not.
744 my @input_nonverbose = ();
746 my $continuation = 0;
747 my $complete_line = undef;
748 while (my $line = <$fh>) {
749 # And stop at the end of the build log. Package details (reported by
750 # the buildd logs) are not important for us. This also prevents false
752 last if index($line, 'Build finished at ') == 0
753 and $line =~ /^Build finished at \d{8}-\d{4}$/;
755 # Detect architecture automatically unless overridden.
757 and index($line, 'dpkg-buildpackage: host architecture ') == 0) {
758 $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end
761 # Ignore compiler warnings for now.
762 next if $line =~ /$warning_regex/o;
764 if (not $option_buildd and index($line, "\033") != -1) { # \033 = esc
765 # Remove all ANSI color sequences which are sometimes used in
766 # non-verbose builds.
767 $line = Term::ANSIColor::colorstrip($line);
768 # Also strip '\0xf' (delete previous character), used by Elinks'
771 # And "ESC(B" which seems to be used on armhf and hurd (not sure
773 $line =~ s/\033\(B//g;
776 # Check if this line indicates a non verbose build.
777 my $non_verbose = is_non_verbose_build($line);
779 # One line may contain multiple commands (";"). Treat each one as
780 # single line. parse_line() is slow, only use it when necessary.
781 my @line = (index($line, ';') == -1)
784 # Ensure newline at the line end - necessary for
785 # correct parsing later.
788 } Text::ParseWords::parse_line(';', 1, $line);
789 foreach my $line (@line) {
793 # Join lines, but leave the "\" in place so it's clear where
794 # the original line break was.
795 chomp $complete_line;
796 $complete_line .= ' ' . $line;
798 # Line continuation, line ends with "\".
799 if ($line =~ /\\$/) {
801 # Start line continuation.
802 if (not defined $complete_line) {
803 $complete_line = $line;
808 # Use the complete line if a line continuation occurred.
809 if (defined $complete_line) {
810 $line = $complete_line;
811 $complete_line = undef;
814 # Ignore lines with no compiler commands.
815 next if not $non_verbose
816 and not $line =~ /$cc_regex_normal/o;
817 # Ignore lines with no filenames with extensions. May miss some
818 # non-verbose builds (e.g. "gcc -o test" [sic!]), but shouldn't be
819 # a problem as the log will most likely contain other non-verbose
820 # commands which are detected.
821 next if not $non_verbose
822 and not $line =~ /$file_extension_regex/o;
824 # Ignore false positives.
826 # `./configure` output.
827 next if not $non_verbose
828 and $line =~ /^(?:checking|[Cc]onfigure:) /;
829 next if $line =~ /^\s*(?:Host\s+)?(?:C(?:\+\+)?\s+)?
830 [Cc]ompiler[\s.]*:?\s+
832 next if $line =~ /^\s*(?:- )?(?:HOST_)?(?:CC|CXX)\s*=\s*$cc_regex_full\s*$/o;
833 # `moc-qt4`, contains '-I/usr/share/qt4/mkspecs/linux-g++' (or
834 # similar for other architectures) which gets recognized as a
835 # compiler line. Ignore it.
836 next if $line =~ m{^/usr/bin/moc-qt4
838 -I/usr/share/qt4/mkspecs/[a-z]+-g\++(?:-64)?
840 # Ignore false positives when the line contains only CC=gcc but no
842 if ($line =~ /(.*)CC=$cc_regex_full(.*)/o) {
845 next if not $before =~ /$cc_regex_normal/o
846 and not $after =~ /$cc_regex_normal/o;
849 # Check if additional hardening options were used. Used to ensure
850 # they are used for the complete build.
851 $harden_pie = 1 if any_flags_used($line, @def_cflags_pie,
853 $harden_bindnow = 1 if any_flags_used($line, @def_ldflags_bindnow);
856 push @input_nonverbose, $non_verbose;
862 # Ignore arch if requested.
863 if (scalar @option_ignore_arch > 0 and $arch) {
864 foreach my $ignore (@option_ignore_arch) {
865 if ($arch eq $ignore) {
866 print "ignoring architecture '$arch'\n";
872 if (scalar @input == 0) {
873 if (not $option_buildd) {
874 print "No compiler commands!\n";
875 $exit |= $exit_code{no_compiler_commands};
877 print "$buildd_tag{no_compiler_commands}||\n";
882 if ($option_buildd) {
883 $statistics{commands} += scalar @input;
886 # Option or auto detected.
888 # The following was partially copied from dpkg-dev 1.16.4.3
889 # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
890 # copyright Raphaël Hertzog <hertzog@debian.org>, Kees Cook
891 # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
892 # later. Keep it in sync.
895 my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch);
897 # Disable unsupported hardening options.
898 if ($cpu =~ /^(?:ia64|alpha|mips|mipsel|hppa)$/ or $arch eq 'arm') {
901 if ($cpu =~ /^(?:ia64|hppa|avr32)$/) {
908 my @cflags = @def_cflags;
909 my @cxxflags = @def_cxxflags;
910 my @cppflags = @def_cppflags;
911 my @ldflags = @def_ldflags;
912 # Check the specified hardening options, same order as dpkg-buildflags.
914 @cflags = (@cflags, @def_cflags_pie);
915 @cxxflags = (@cxxflags, @def_cflags_pie);
916 @ldflags = (@ldflags, @def_ldflags_pie);
919 @cflags = (@cflags, @def_cflags_stack);
920 @cxxflags = (@cxxflags, @def_cflags_stack);
922 if ($harden_fortify) {
923 @cflags = (@cflags, @def_cflags_fortify);
924 @cxxflags = (@cxxflags, @def_cflags_fortify);
925 @cppflags = (@cppflags, @def_cppflags_fortify);
927 if ($harden_format) {
928 @cflags = (@cflags, @def_cflags_format);
929 @cxxflags = (@cxxflags, @def_cflags_format);
932 @ldflags = (@ldflags, @def_ldflags_relro);
934 if ($harden_bindnow) {
935 @ldflags = (@ldflags, @def_ldflags_bindnow);
938 # Stores normal CFLAGS when @cflags_ada are temporarily used.
941 my @cflags_ada = @cflags;
942 # Ada doesn't support format hardening flags, see #680117 for more
943 # information. Filter them out if ada is used.
944 if ($ada and $harden_format) {
947 foreach my $flag (@def_cflags_format) {
948 $ok = 0 if $_ eq $flag;
954 # Hack to fix cppflags_fortify_broken() if --ignore-flag
955 # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works
956 # as long as @def_cppflags_fortify contains only one variable.
957 if (scalar @def_cppflags_fortify == 0) {
961 # Ignore flags for this arch if requested.
962 if ($arch and exists $option_ignore_arch_flag{$arch}) {
963 my @local_flag_refs = (\@cflags, \@cxxflags, \@cppflags, \@ldflags);
965 remove_flags(\@local_flag_refs,
967 @{$option_ignore_arch_flag{$arch}});
970 my @ignore_line = @option_ignore_line;
971 # Ignore lines for this arch if requested.
972 if ($arch and exists $option_ignore_arch_line{$arch}) {
973 @ignore_line = (@ignore_line, @{$option_ignore_arch_line{$arch}});
977 for (my $i = 0; $i < scalar @input; $i++) {
978 my $line = $input[$i];
980 # Ignore line if requested.
981 foreach my $ignore (@ignore_line) {
982 next LINE if $line =~ /$ignore/;
986 if ($input_nonverbose[$i]
987 and is_non_verbose_build($line, $input[$i + 1], \$skip)) {
988 if (not $option_buildd) {
989 error_non_verbose_build($line);
990 $exit |= $exit_code{non_verbose_build};
992 $statistics{commands_nonverbose}++;
996 # Even if it's a verbose build, we might have to skip this line.
999 # Remove everything until and including the compiler command. Makes
1000 # checks easier and faster.
1001 $line =~ s/^.*?$cc_regex//o;
1002 # "([...] test.c)" is not detected as 'test.c' - fix this by removing
1003 # the brace and similar characters at the line end.
1004 $line =~ s/['")]+$//;
1006 # Skip unnecessary tests when only preprocessing.
1007 my $flag_preprocess = 0;
1014 # Preprocess, compile, assemble.
1015 if ($line =~ /\s(-E|-S|-c)\b/) {
1017 $flag_preprocess = 1 if $1 eq '-E';
1018 $compile = 1 if $1 eq '-S' or $1 eq '-c';
1019 # Dependency generation for Makefiles. The other flags (-MF -MG -MP
1020 # -MT -MQ) are always used with -M/-MM.
1021 } elsif ($line =~ /\s(?:-M|-MM)\b/) {
1023 # Otherwise assume we are linking.
1028 # -MD/-MMD also cause dependency generation, but they don't imply -E!
1029 if ($line =~ /\s(?:-MD|-MMD)\b/) {
1031 $flag_preprocess = 0;
1034 # Dependency generation for Makefiles, no preprocessing or other flags
1036 next if $dependency;
1038 # Get all file extensions on this line.
1039 my @extensions = $line =~ /$file_extension_regex/go;
1040 # Ignore all unknown extensions to speedup the search below.
1041 @extensions = grep { exists $extension{$_} } @extensions;
1043 # These file types don't require preprocessing.
1044 if (extension_found(\%extensions_no_preprocess, @extensions)) {
1047 # These file types require preprocessing.
1048 if (extension_found(\%extensions_preprocess, @extensions)) {
1052 if (not $flag_preprocess) {
1053 # If there are source files then it's compiling/linking in one
1054 # step and we must check both. We only check for source files
1055 # here, because header files cause too many false positives.
1056 if (extension_found(\%extensions_compile_link, @extensions)) {
1057 # Assembly files don't need CFLAGS.
1058 if (not extension_found(\%extensions_compile, @extensions)
1059 and extension_found(\%extensions_no_compile, @extensions)) {
1061 # But the rest does.
1065 # No compilable extensions found, either linking or compiling
1068 # If there are also no object files we are just compiling headers
1069 # (.h -> .h.gch). Don't check for linker flags in this case. Due
1070 # to our liberal checks for compiler lines, this also reduces the
1071 # number of false positives considerably.
1073 and not extension_found(\%extensions_object, @extensions)) {
1078 my $compile_cpp = 0;
1079 my $compile_ada = 0;
1080 # Assume CXXFLAGS are required when a C++ file is specified in the
1083 and extension_found(\%extensions_compile_cpp, @extensions)) {
1086 # Ada needs special CFLAGS, use them if only ada files are compiled.
1089 and array_equal(\@extensions,
1090 \@source_no_preprocess_compile_ada)) {
1092 @cflags_backup = @cflags;
1093 @cflags = @cflags_ada;
1096 if ($option_buildd) {
1097 $statistics{preprocess}++ if $preprocess;
1098 $statistics{compile}++ if $compile;
1099 $statistics{compile_cpp}++ if $compile_cpp;
1100 $statistics{link}++ if $link;
1103 # Check hardening flags.
1105 if ($compile and not all_flags_used($line, \@missing, @cflags)
1106 # Libraries linked with -fPIC don't have to (and can't) be
1107 # linked with -fPIE as well. It's no error if only PIE flags
1109 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1110 # Assume dpkg-buildflags returns the correct flags.
1111 and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) {
1112 if (not $option_buildd) {
1113 error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1114 $exit |= $exit_code{flags_missing};
1116 $statistics{compile_missing}++;
1118 } elsif ($compile_cpp and not all_flags_used($line, \@missing, @cflags)
1119 # Libraries linked with -fPIC don't have to (and can't) be
1120 # linked with -fPIE as well. It's no error if only PIE flags
1122 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_cflags_pie)
1123 # Assume dpkg-buildflags returns the correct flags.
1124 and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) {
1125 if (not $option_buildd) {
1126 error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1127 $exit |= $exit_code{flags_missing};
1129 $statistics{compile_cpp_missing}++;
1133 and (not all_flags_used($line, \@missing, @cppflags)
1134 # The fortify flag might be overwritten, detect that.
1136 and cppflags_fortify_broken($line, \@missing)))
1137 # Assume dpkg-buildflags returns the correct flags.
1138 and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) {
1139 if (not $option_buildd) {
1140 error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1141 $exit |= $exit_code{flags_missing};
1143 $statistics{preprocess_missing}++;
1146 if ($link and not all_flags_used($line, \@missing, @ldflags)
1147 # Same here, -fPIC conflicts with -fPIE.
1148 and not pic_pie_conflict($line, $harden_pie, \@missing, @def_ldflags_pie)
1149 # Assume dpkg-buildflags returns the correct flags.
1150 and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) {
1151 if (not $option_buildd) {
1152 error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]);
1153 $exit |= $exit_code{flags_missing};
1155 $statistics{link_missing}++;
1159 # Restore normal CFLAGS.
1161 @cflags = @cflags_backup;
1166 # Print statistics for buildd mode, only output in this mode.
1167 if ($option_buildd) {
1170 if ($statistics{preprocess_missing}) {
1171 push @warning, sprintf 'CPPFLAGS %d (of %d)',
1172 $statistics{preprocess_missing},
1173 $statistics{preprocess};
1175 if ($statistics{compile_missing}) {
1176 push @warning, sprintf 'CFLAGS %d (of %d)',
1177 $statistics{compile_missing},
1178 $statistics{compile};
1180 if ($statistics{compile_cpp_missing}) {
1181 push @warning, sprintf 'CXXFLAGS %d (of %d)',
1182 $statistics{compile_cpp_missing},
1183 $statistics{compile_cpp};
1185 if ($statistics{link_missing}) {
1186 push @warning, sprintf 'LDFLAGS %d (of %d)',
1187 $statistics{link_missing},
1190 if (scalar @warning) {
1191 local $" = ', '; # array join string
1192 print "$buildd_tag{flags_missing}|@warning missing|\n";
1195 if ($statistics{commands_nonverbose}) {
1196 printf "$buildd_tag{non_verbose_build}|%d (of %d) hidden|\n",
1197 $statistics{commands_nonverbose},
1198 $statistics{commands},
1210 blhc - build log hardening check, checks build logs for missing hardening flags
1214 B<blhc> [I<options>] I<< <dpkg-buildpackage build log file>.. >>
1218 blhc is a small tool which checks build logs for missing hardening flags. It's
1219 licensed under the GPL 3 or later.
1221 It's designed to check build logs generated by Debian's dpkg-buildpackage (or
1222 tools using dpkg-buildpackage like pbuilder or the official buildd build logs)
1223 to help maintainers detect missing hardening flags in their packages.
1225 Only gcc is detected as compiler at the moment. If other compilers support
1226 hardening flags as well, please report them.
1228 If there's no output, no flags are missing and the build log is fine.
1236 Force check for all +all (+pie, +bindnow) hardening flags. By default it's
1239 =item B<--arch> I<architecture>
1241 Set the specific architecture (e.g. amd64, armel, etc.), automatically
1242 disables hardening flags not available on this architecture. Is detected
1243 automatically if dpkg-buildpackage is used.
1247 Force check for all +bindnow hardening flags. By default it's auto detected.
1251 Special mode for buildds when automatically parsing log files. The following
1252 changes are in effect:
1258 Print tags instead of normal warnings, see L</"BUILDD TAGS"> for a list of
1263 Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
1268 Don't require Term::ANSIColor.
1272 Return exit code 0, unless there was a error (-I, -W messages don't count as
1279 Use colored (ANSI) output for warning messages.
1281 =item B<--ignore-arch> I<arch>
1283 Ignore build logs from architectures matching I<arch>. I<arch> is a string.
1285 Used to prevent false positives. This option can be specified multiple times.
1287 =item B<--ignore-arch-flag> I<arch>:I<flag>
1289 Like B<--ignore-flag>, but only ignore flag on I<arch>.
1291 =item B<--ignore-arch-line> I<arch>:I<line>
1293 Like B<--ignore-line>, but only ignore line on I<arch>.
1295 =item B<--ignore-flag> I<flag>
1297 Don't print an error when the specific flag is missing in a compiler line.
1298 I<flag> is a string.
1300 Used to prevent false positives. This option can be specified multiple times.
1302 =item B<--ignore-line> I<regex>
1304 Ignore lines matching the given Perl regex. I<regex> is automatically anchored
1305 at the beginning and end of the line to prevent false negatives.
1307 B<NOTE>: Not the input lines are checked, but the lines which are displayed in
1308 warnings (which have line continuation resolved).
1310 Used to prevent false positives. This option can be specified multiple times.
1314 Force check for all +pie hardening flags. By default it's auto detected.
1316 =item B<-h -? --help>
1318 Print available options.
1322 Print version number and license.
1326 Auto detection for B<--pie> and B<--bindnow> only works if at least one
1327 command uses the required hardening flag (e.g. -fPIE). Then it's required for
1328 all other commands as well.
1332 Normal usage, parse a single log file.
1334 blhc path/to/log/file
1336 If there's no output, no flags are missing and the build log is fine.
1338 Parse multiple log files. The exit code is ORed over all files.
1340 blhc path/to/directory/with/log/files/*
1342 Don't treat missing C<-g> as error:
1344 blhc --ignore-flag -g path/to/log/file
1346 Don't treat missing C<-pie> on kfreebsd-amd64 as error:
1348 blhc --ignore-arch-flag kfreebsd-amd64:-pie path/to/log/file
1350 Ignore lines consisting exactly of C<./script gcc file> which would cause a
1353 blhc --ignore-line '\./script gcc file' path/to/log/file
1355 Ignore lines matching C<./script gcc file> somewhere in the line.
1357 blhc --ignore-line '.*\./script gcc file.*' path/to/log/file
1359 Use blhc with pbuilder.
1361 pbuilder path/to/package.dsc | tee path/log/file
1362 blhc path/to/file || echo flags missing
1366 The following tags are used in I<--buildd> mode. In braces the additional data
1371 =item B<I-hardening-wrapper-used>
1373 The package uses hardening-wrapper which intercepts calls to gcc and adds
1374 hardening flags. The build log doesn't contain any hardening flags and thus
1375 can't be checked by blhc.
1377 =item B<W-compiler-flags-hidden> (summary of hidden lines)
1379 Build log contains lines which hide the real compiler flags. For example:
1386 Most of the time either C<export V=1> or C<export verbose=1> in
1387 F<debian/rules> fixes builds with hidden compiler flags. Sometimes C<.SILENT>
1388 in a F<Makefile> must be removed. And as last resort the F<Makefile> must be
1389 patched to remove the C<@>s hiding the real compiler commands.
1391 =item B<W-dpkg-buildflags-missing> (summary of missing flags)
1393 CPPFLAGS, CFLAGS, CXXFLAGS, LDFLAGS missing.
1395 =item B<I-invalid-cmake-used> (version)
1397 By default CMake ignores CPPFLAGS thus missing those hardening flags. Debian
1398 patched CMake in versions 2.8.7-1 and 2.8.7-2 to respect CPPFLAGS, but this
1399 patch was rejected by upstream and later reverted in Debian. Thus those two
1400 versions show correct usage of CPPFLAGS even if the package doesn't correctly
1401 handle them (for example by passing them to CFLAGS). To prevent false
1402 negatives just blacklist those two versions.
1404 =item B<I-no-compiler-commands>
1406 No compiler commands were detected. Either the log contains none or they were
1407 not correctly detected by blhc (please report the bug in this case).
1413 The exit status is a "bit mask", each listed status is ORed when the error
1414 condition occurs to get the result.
1424 No compiler commands were found.
1428 Invalid arguments/options given to blhc.
1436 Missing hardening flags.
1440 Hardening wrapper detected, no tests performed.
1444 Invalid CMake version used. See B<I-invalid-cmake-used> under L</"BUILDD
1445 TAGS"> for a detailed explanation.
1451 Simon Ruderich, E<lt>simon@ruderich.orgE<gt>
1453 Thanks to to Bernhard R. Link E<lt>brlink@debian.orgE<gt> and Jaria Alto
1454 E<lt>jari.aalto@cante.netE<gt> for their valuable input and suggestions.
1456 =head1 LICENSE AND COPYRIGHT
1458 Copyright (C) 2012 by Simon Ruderich
1460 This program is free software: you can redistribute it and/or modify
1461 it under the terms of the GNU General Public License as published by
1462 the Free Software Foundation, either version 3 of the License, or
1463 (at your option) any later version.
1465 This program is distributed in the hope that it will be useful,
1466 but WITHOUT ANY WARRANTY; without even the implied warranty of
1467 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1468 GNU General Public License for more details.
1470 You should have received a copy of the GNU General Public License
1471 along with this program. If not, see <http://www.gnu.org/licenses/>.
1475 L<hardening-check(1)>, L<dpkg-buildflags(1)>