X-Git-Url: https://ruderich.org/simon/gitweb/?p=blhc%2Fblhc.git;a=blobdiff_plain;f=bin%2Fblhc;h=e84b12b5e6abf504810b0c943b7350507ac69df9;hp=d2a8771515e5e01d8a3890db542cb7cf08244f21;hb=f0a9d412466ca504fb2e279e1d98718a9c2bab28;hpb=7d9ae6314e499d9e76bc32a0e1c4a5686bb59158 diff --git a/bin/blhc b/bin/blhc index d2a8771..e84b12b 100755 --- a/bin/blhc +++ b/bin/blhc @@ -2,7 +2,7 @@ # Build log hardening check, checks build logs for missing hardening flags. -# Copyright (C) 2012-2015 Simon Ruderich +# Copyright (C) 2012-2019 Simon Ruderich # # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by @@ -24,7 +24,7 @@ use warnings; use Getopt::Long (); use Text::ParseWords (); -our $VERSION = '0.05'; +our $VERSION = '0.10'; # CONSTANTS/VARIABLES @@ -33,13 +33,16 @@ our $VERSION = '0.05'; my $cc_regex = qr/ (? 1 } ( @source_preprocess_compile_cpp, @source_no_preprocess_compile_cpp, ); +my %extensions_ada = map { $_ => 1 } ( + @source_no_preprocess_compile_ada, + @source_no_preprocess_no_compile_ada, +); +my %extensions_fortran = map { $_ => 1 } ( + @source_no_preprocess_compile_fortran, + @source_preprocess_compile_fortran, +); my %extensions_object = map { $_ => 1 } ( @object, ); @@ -198,11 +222,17 @@ my @def_cflags_fortify = ( # fortify needs at least -O1, but -O2 is recommended anyway ); my @def_cflags_stack = ( - '-fstack-protector', + '-fstack-protector', # keep first, used by cflags_stack_broken() '--param[= ]ssp-buffer-size=4', ); my @def_cflags_stack_strong = ( - '-fstack-protector-strong', + '-fstack-protector-strong', # keep first, used by cflags_stack_broken() +); +my @def_cflags_stack_bad = ( + # Blacklist all stack protector options for simplicity. + '-fno-stack-protector', + '-fno-stack-protector-all', + '-fno-stack-protector-strong', ); my @def_cflags_pie = ( '-fPIE', @@ -246,6 +276,7 @@ my @flag_refs = ( \@def_cflags_fortify, \@def_cflags_stack, \@def_cflags_stack_strong, + \@def_cflags_stack_bad, \@def_cflags_pie, \@def_cxxflags, \@def_cppflags, @@ -325,7 +356,7 @@ sub array_equal { } sub error_flags { - my ($message, $missing_flags_ref, $flag_renames_ref, $line) = @_; + my ($message, $missing_flags_ref, $flag_renames_ref, $line, $number) = @_; # Get string value of qr//-escaped regexps and if requested rename them. my @missing_flags = map { @@ -333,6 +364,7 @@ sub error_flags { } @{$missing_flags_ref}; my $flags = join ' ', @missing_flags; + printf '%d:', $number if defined $number; printf '%s (%s)%s %s', error_color($message, 'red'), $flags, error_color(':', 'yellow'), $line; @@ -340,8 +372,9 @@ sub error_flags { return; } sub error_non_verbose_build { - my ($line) = @_; + my ($line, $number) = @_; + printf '%d:', $number if defined $number; printf '%s%s %s', error_color('NONVERBOSE BUILD', 'red'), error_color(':', 'yellow'), @@ -401,21 +434,61 @@ sub all_flags_used { @{$missing_flags_ref} = @missing_flags; return 0; } +# Check if any of \@bad_flags occurs after $good_flag. Doesn't check if +# $good_flag is present. +sub flag_overwritten { + my ($line, $good_flag, $bad_flags) = @_; + + if (not any_flags_used($line, @{$bad_flags})) { + return 0; + } + + my $bad_pos = 0; + foreach my $flag (@{$bad_flags}) { + while ($line =~ /$flag/g) { + if ($bad_pos < $+[0]) { + $bad_pos = $+[0]; + } + } + } + my $good_pos = 0; + while ($line =~ /$good_flag/g) { + $good_pos = $+[0]; + } + if ($good_pos > $bad_pos) { + return 0; + } + return 1; +} sub cppflags_fortify_broken { my ($line, $missing_flags) = @_; - # This doesn't take the position into account, but is a simple solution. - # And if the build system tries to force -D_FORTIFY_SOURCE=0/1, something - # is wrong anyway. + # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2! + my $fortify_source = $def_cppflags_fortify[0]; - if (any_flags_used($line, @def_cppflags_fortify_bad)) { - # $def_cppflags_fortify[0] must be -D_FORTIFY_SOURCE=2! - push @{$missing_flags}, $def_cppflags_fortify[0]; - return 1; + # Some build systems enable/disable fortify source multiple times, check + # the final result. + if (not flag_overwritten($line, + $fortify_source, + \@def_cppflags_fortify_bad)) { + return 0; } + push @{$missing_flags}, $fortify_source; + return 1; +} - return 0; +sub cflags_stack_broken { + my ($line, $missing_flags, $strong) = @_; + + my $flag = $strong ? $def_cflags_stack_strong[0] + : $def_cflags_stack[0]; + + if (not flag_overwritten($line, $flag, \@def_cflags_stack_bad)) { + return 0; + } + push @{$missing_flags}, $flag; + return 1; } # Modifies $missing_flags_ref array. @@ -441,7 +514,7 @@ sub pic_pie_conflict { } sub is_non_verbose_build { - my ($line, $next_line, $skip_ref) = @_; + my ($line, $skip_ref, $input_ref, $line_offset, $line_count) = @_; if ($line =~ /$libtool_regex/o) { # libtool's --silent hides the real compiler flags. @@ -471,7 +544,8 @@ sub is_non_verbose_build { return 0 if $line =~ /^\s*C\+\+.+?:\s+(?:yes|no)\s*$/; return 0 if $line =~ /^\s*C\+\+ Library: stdc\+\+$/; # "Compiling" non binary files. - return 0 if $line =~ /^\s*Compiling \S+\.(?:py|el)['"]?\s*(?:\.\.\.)?$/; + return 0 if $line =~ /^\s*Compiling \S+\.(?:py|pyx|el)['"]?\s*(?:\.\.\.|because it changed\.)?$/; + return 0 if $line =~ /^\s*[Cc]ompiling catalog \S+\.po\b/; # "Compiling" with no file name. if ($line =~ /^\s*[Cc]ompiling\s+(.+?)(?:\.\.\.)?$/) { # $file_extension_regex may need spaces around the filename. @@ -481,25 +555,30 @@ sub is_non_verbose_build { my $file = $1; # On the first pass we only check if this line is verbose or not. - return 1 if not defined $next_line; + return 1 if not defined $input_ref; - # Second pass, we have access to the next line. + # Second pass, we have access to the next lines. ${$skip_ref} = 0; # CMake and other build systems print the non-verbose messages also when # building verbose. If a compiler and the file name occurs in the next - # line, treat it as verbose build. + # lines, treat it as verbose build. if (defined $file) { # Get filename, we can't use the complete path as only parts of it are # used in the real compiler command. $file =~ m{/([^/\s]+)$}; $file = $1; - if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) { - # Not a non-verbose line, but we still have to skip the current line - # as it doesn't contain any compiler commands. - ${$skip_ref} = 1; - return 0; + for (my $i = 1; $i <= $line_count; $i++) { + my $next_line = $input_ref->[$line_offset + $i]; + last unless defined $next_line; + + if (index($next_line, $file) != -1 and $next_line =~ /$cc_regex/o) { + # Not a non-verbose line, but we still have to skip the + # current line as it doesn't contain any compiler commands. + ${$skip_ref} = 1; + return 0; + } } } @@ -573,7 +652,9 @@ my @option_ignore_arch_line = (); my $option_all = 0; my $option_arch = undef; my $option_buildd = 0; +my $option_debian = 0; $option_color = 0; +my $option_line_numbers = 0; if (not Getopt::Long::GetOptions( 'help|h|?' => \$option_help, 'version' => \$option_version, @@ -591,6 +672,8 @@ if (not Getopt::Long::GetOptions( 'color' => \$option_color, 'arch=s' => \$option_arch, 'buildd' => \$option_buildd, + 'debian' => \$option_debian, + 'line-numbers' => \$option_line_numbers, )) { require Pod::Usage; Pod::Usage::pod2usage(2); @@ -601,7 +684,7 @@ if ($option_help) { } if ($option_version) { print <<"EOF"; -blhc $VERSION Copyright (C) 2012-2015 Simon Ruderich +blhc $VERSION Copyright (C) 2012-2019 Simon Ruderich This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -709,12 +792,22 @@ foreach my $file (@ARGV) { my $harden_bindnow = $option_bindnow; # defaults to 0 my $harden_pie = $option_pie; # defaults to 0 - # Does this build log use ada? Ada also uses gcc as compiler but uses - # different CFLAGS. But only perform ada checks if an ada compiler used - # for performance reasons. - my $ada = 0; + # Number of parallel jobs to prevent false positives when detecting + # non-verbose builds. As not all jobs declare the number of parallel jobs + # use a large enough default. + my $parallel = 10; + + # Don't check for PIE flags if automatically applied by the compiler. Only + # used in buildd and Debian mode. + my $disable_harden_pie = 0; + if ($option_debian) { + $disable_harden_pie = 1; + } + my $number = 0; while (my $line = <$fh>) { + $number++; + # Detect architecture automatically unless overridden. For buildd logs # only, doesn't use the dpkg-buildpackage header. Necessary to ignore # build logs which aren't built (wrong architecture, build error, @@ -736,6 +829,10 @@ foreach my $file (@ARGV) { # flags are not checked. # # Strong stack protector is used since dpkg 1.17.11. + # + # Recent GCC versions automatically use PIE (only on supported + # architectures) and dpkg respects this properly since 1.18.15 and + # doesn't pass PIE flags manually. if ($option_buildd and index($line, 'Toolchain package versions: ') == 0) { require Dpkg::Version; @@ -750,6 +847,9 @@ foreach my $file (@ARGV) { if (Dpkg::Version::version_compare($1, '1.17.11') >= 0) { $disable_strong = 0; } + if (Dpkg::Version::version_compare($1, '1.18.15') >= 0) { + $disable_harden_pie = 1; + } } if ($disable) { @@ -800,11 +900,11 @@ foreach my $file (@ARGV) { } next FILE; } + } - # Ada compiler. - if ($line =~ /\bgnat\b/) { - $ada = 1; - } + # This flags is not always available, but if it is use it. + if ($line =~ /^DEB_BUILD_OPTIONS=.*\bparallel=(\d+)/) { + $parallel = $1 * 2; } # We skip over unimportant lines at the beginning of the log to @@ -818,11 +918,15 @@ foreach my $file (@ARGV) { # is_non_verbose_build() (which is quite slow) in the second loop when # it's already clear if a line is non-verbose or not. my @input_nonverbose = (); + # Input line number. + my @input_number = (); my $continuation = 0; my $complete_line = undef; my $non_verbose; while (my $line = <$fh>) { + $number++; + # And stop at the end of the build log. Package details (reported by # the buildd logs) are not important for us. This also prevents false # positives. @@ -835,6 +939,10 @@ foreach my $file (@ARGV) { # Detect architecture automatically unless overridden. if (not $arch + and index($line, 'dpkg-buildpackage: info: host architecture ') == 0) { + $arch = substr $line, 43, -1; # -1 to ignore '\n' at the end + # Older versions of dpkg-buildpackage + } elsif (not $arch and index($line, 'dpkg-buildpackage: host architecture ') == 0) { $arch = substr $line, 37, -1; # -1 to ignore '\n' at the end @@ -846,6 +954,7 @@ foreach my $file (@ARGV) { } } + next if $line =~ /^\s*#/; # Ignore compiler warnings for now. next if $line =~ /$warning_regex/o; @@ -863,7 +972,7 @@ foreach my $file (@ARGV) { # Check if this line indicates a non verbose build. my $skip = 0; - $non_verbose |= is_non_verbose_build($line, undef, \$skip); + $non_verbose |= is_non_verbose_build($line, \$skip); next if $skip; # One line may contain multiple commands (";"). Treat each one as @@ -942,6 +1051,21 @@ foreach my $file (@ARGV) { next if not $before =~ /$cc_regex_normal/o and not $after =~ /$cc_regex_normal/o; } + # Ignore false positives caused by gcc -v. It outputs a line + # looking like a normal compiler line but which is sometimes + # missing hardening flags, although the normal compiler line + # contains them. + next if $line =~ m{^\s+/usr/lib/gcc/$cc_regex_full_prefix/ + [0-9.]+/cc1(?:plus)?}xo; + # Ignore false positive with `rm` which may remove files which + # look like a compiler executable thus causing the line to be + # treated as a normal compiler line. + next if $line =~ m{^\s*rm\s+}; + next if $line =~ m{^\s*dwz\s+}; + # Some build systems emit "gcc > file". + next if $line =~ m{$cc_regex_normal\s*>\s*\S+}o; + # Hex output may contain "cc". + next if $line =~ m#(?:\b[0-9a-fA-F]{2,}\b\s*){5}#; # Check if additional hardening options were used. Used to ensure # they are used for the complete build. @@ -951,6 +1075,7 @@ foreach my $file (@ARGV) { push @input, $line; push @input_nonverbose, $non_verbose; + push @input_number, $number if $option_line_numbers; } } @@ -982,20 +1107,49 @@ foreach my $file (@ARGV) { # Option or auto detected. if ($arch) { - # The following was partially copied from dpkg-dev 1.17.11 - # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()), - # copyright Raphaël Hertzog , Kees Cook - # , Canonical, Ltd. licensed under GPL version 2 or - # later. Keep it in sync. + # The following was partially copied from dpkg-dev 1.19.7 + # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, _add_build_flags()), + # copyright Raphaël Hertzog , Guillem Jover + # , Kees Cook , Canonical, Ltd. + # licensed under GPL version 2 or later. Keep it in sync. require Dpkg::Arch; - my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch); + my ($os, $cpu); + # Recent dpkg versions use a quadruplet for arch. Support both. + eval { + (undef, undef, $os, $cpu) = Dpkg::Arch::debarch_to_debtuple($arch); + }; + if ($@) { + (undef, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($arch); + } + + my %builtin_pie_arch = map { $_ => 1 } qw( + amd64 + arm64 + armel + armhf + hurd-i386 + i386 + kfreebsd-amd64 + kfreebsd-i386 + mips + mipsel + mips64el + powerpc + ppc64 + ppc64el + riscv64 + s390x + sparc + sparc64 + ); # Disable unsupported hardening options. - if ($os !~ /^(?:linux|knetbsd|hurd)$/ or $cpu =~ /^(?:hppa|avr32)$/) { + if ($os !~ /^(?:linux|kfreebsd|knetbsd|hurd)$/ + or $cpu =~ /^(?:hppa|avr32)$/) { $harden_pie = 0; } - if ($cpu =~ /^(?:ia64|alpha|hppa)$/ or $arch eq 'arm') { + if ($cpu =~ /^(?:ia64|alpha|hppa|nios2)$/ or $arch eq 'arm') { $harden_stack = 0; $harden_stack_strong = 0; } @@ -1003,6 +1157,10 @@ foreach my $file (@ARGV) { $harden_relro = 0; $harden_bindnow = 0; } + + if ($disable_harden_pie and exists $builtin_pie_arch{$arch}) { + $harden_pie = 0; + } } # Default values. @@ -1039,21 +1197,16 @@ foreach my $file (@ARGV) { @ldflags = (@ldflags, @def_ldflags_bindnow); } - # Stores normal CFLAGS when @cflags_ada are temporarily used. - my @cflags_backup; - # Ada CFLAGS, only set if ada is used. - my @cflags_ada; # Ada doesn't support format hardening flags, see #680117 for more - # information. Filter them out if ada is used. - if ($ada and $harden_format) { - @cflags_ada = grep { - my $ok = 1; - foreach my $flag (@def_cflags_format) { - $ok = 0 if $_ eq $flag; - } - $ok; - } @cflags; - } + # information. Same for fortran. + my @cflags_backup; + my @cflags_noformat = grep { + my $ok = 1; + foreach my $flag (@def_cflags_format) { + $ok = 0 if $_ eq $flag; + } + $ok; + } @cflags; # Hack to fix cppflags_fortify_broken() if --ignore-flag # -D_FORTIFY_SOURCE=2 is used to ignore missing fortification. Only works @@ -1088,9 +1241,10 @@ LINE: my $skip = 0; if ($input_nonverbose[$i] - and is_non_verbose_build($line, $input[$i + 1], \$skip)) { + and is_non_verbose_build($line, \$skip, + \@input, $i, $parallel)) { if (not $option_buildd) { - error_non_verbose_build($line); + error_non_verbose_build($line, $input_number[$i]); $exit |= $exit_code{non_verbose_build}; } else { $statistics{commands_nonverbose}++; @@ -1101,6 +1255,8 @@ LINE: # is_non_verbose_build()). next if $skip; + my $orig_line = $line; + # Remove everything until and including the compiler command. Makes # checks easier and faster. $line =~ s/^.*?$cc_regex//o; @@ -1151,7 +1307,11 @@ LINE: } # These file types require preprocessing. if (extension_found(\%extensions_preprocess, @extensions)) { - $preprocess = 1; + # Prevent false positives with "libtool: link: g++ -include test.h + # .." compiler lines. + if ($orig_line !~ /$libtool_link_regex/o) { + $preprocess = 1; + } } if (not $flag_preprocess) { @@ -1181,21 +1341,24 @@ LINE: } my $compile_cpp = 0; - my $compile_ada = 0; + my $restore_cflags = 0; # Assume CXXFLAGS are required when a C++ file is specified in the # compiler line. if ($compile and extension_found(\%extensions_compile_cpp, @extensions)) { $compile = 0; $compile_cpp = 1; - # Ada needs special CFLAGS, use them if only ada files are compiled. - } elsif ($ada - and $compile - and array_equal(\@extensions, - \@source_no_preprocess_compile_ada)) { - $compile_ada = 1; + # Ada needs special CFLAGS + } elsif (extension_found(\%extensions_ada, @extensions)) { + $restore_cflags = 1; + $preprocess = 0; # Ada uses no CPPFLAGS + @cflags_backup = @cflags; + @cflags = @cflags_noformat; + # Same for fortran + } elsif (extension_found(\%extensions_fortran, @extensions)) { + $restore_cflags = 1; @cflags_backup = @cflags; - @cflags = @cflags_ada; + @cflags = @cflags_noformat; } if ($option_buildd) { @@ -1215,7 +1378,10 @@ LINE: # Check hardening flags. my @missing; - if ($compile and not all_flags_used($line, \@missing, @cflags) + if ($compile and (not all_flags_used($line, \@missing, @cflags) + or (($harden_stack or $harden_stack_strong) + and cflags_stack_broken($line, \@missing, + $harden_stack_strong))) # Libraries linked with -fPIC don't have to (and can't) be # linked with -fPIE as well. It's no error if only PIE flags # are missing. @@ -1223,7 +1389,8 @@ LINE: # Assume dpkg-buildflags returns the correct flags. and index($line, '`dpkg-buildflags --get CFLAGS`') == -1) { if (not $option_buildd) { - error_flags('CFLAGS missing', \@missing, \%flag_renames, $input[$i]); + error_flags('CFLAGS missing', \@missing, \%flag_renames, + $input[$i], $input_number[$i]); $exit |= $exit_code{flags_missing}; } else { $statistics{compile_missing}++; @@ -1236,7 +1403,8 @@ LINE: # Assume dpkg-buildflags returns the correct flags. and index($line, '`dpkg-buildflags --get CXXFLAGS`') == -1) { if (not $option_buildd) { - error_flags('CXXFLAGS missing', \@missing, \%flag_renames, $input[$i]); + error_flags('CXXFLAGS missing', \@missing, \%flag_renames, + $input[$i], $input_number[$i]); $exit |= $exit_code{flags_missing}; } else { $statistics{compile_cpp_missing}++; @@ -1250,7 +1418,8 @@ LINE: # Assume dpkg-buildflags returns the correct flags. and index($line, '`dpkg-buildflags --get CPPFLAGS`') == -1) { if (not $option_buildd) { - error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $input[$i]); + error_flags('CPPFLAGS missing', \@missing, \%flag_renames, + $input[$i], $input_number[$i]); $exit |= $exit_code{flags_missing}; } else { $statistics{preprocess_missing}++; @@ -1262,7 +1431,8 @@ LINE: # Assume dpkg-buildflags returns the correct flags. and index($line, '`dpkg-buildflags --get LDFLAGS`') == -1) { if (not $option_buildd) { - error_flags('LDFLAGS missing', \@missing, \%flag_renames, $input[$i]); + error_flags('LDFLAGS missing', \@missing, \%flag_renames, + $input[$i], $input_number[$i]); $exit |= $exit_code{flags_missing}; } else { $statistics{link_missing}++; @@ -1270,7 +1440,7 @@ LINE: } # Restore normal CFLAGS. - if ($compile_ada) { + if ($restore_cflags) { @cflags = @cflags_backup; } } @@ -1391,10 +1561,20 @@ error). =back +=item B<--debian> + +Apply Debian-specific settings. At the moment this only disables checking for +PIE which is automatically applied by Debian's GCC and no longer requires a +compiler command line argument. + =item B<--color> Use colored (ANSI) output for warning messages. +=item B<--line-numbers> + +Display line numbers. + =item B<--ignore-arch> I Ignore build logs from architectures matching I. I is a string. @@ -1478,6 +1658,13 @@ Use blhc with pbuilder. pbuilder path/to/package.dsc | tee path/log/file blhc path/to/file || echo flags missing +Assume this build log was created on a Debian system and thus don't warn about +missing PIE flags if the current architecture injects them automatically (this +is enabled in buildd mode per default). C<--arch> is necessary if the build +log contains no architecture information as written by dpkg-buildpackage. + + blhc --debian --all --arch=amd64 path/to/log/file + =head1 BUILDD TAGS The following tags are used in I<--buildd> mode. In braces the additional data @@ -1572,7 +1759,7 @@ Ejari.aalto@cante.netE for their valuable input and suggestions. =head1 LICENSE AND COPYRIGHT -Copyright (C) 2012-2015 by Simon Ruderich +Copyright (C) 2012-2019 by Simon Ruderich This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by