use Getopt::Long ();
use Term::ANSIColor ();
+use Text::ParseWords ();
our $VERSION = '0.01';
+# CONSTANTS/VARIABLES
+
+# Regex to catch compiler commands.
+my $cc_regex = qr/(?:[a-z0-9_]+-(?:linux-|kfreebsd-)?gnu(?:eabi|eabihf)?-)?
+ (?<!\.)(?:cc|gcc|g\+\+|c\+\+)
+ (?:-[\d.]+)?/x;
+# Regex to catch (GCC) compiler warnings.
+my $warning_regex = qr/^(.+?):([0-9]+):[0-9]+: warning: (.+?) \[(.+?)\]$/;
+
+# Regex for source files which require preprocessing.
+my $source_preprocess_compile_regex = qr/
+ # C
+ c
+ # Objective-C
+ | m
+ # C++
+ | cc | cp | cxx | cpp | CPP | c\+\+ | C
+ # Objective-C++
+ | mm | M
+ # Fortran
+ | F | FOR | fpp | FPP | FTN | F90 | F95 | F03 | F08
+ /x;
+my $source_preprocess_no_compile_regex = qr/
+ # Assembly
+ s
+ /x;
+my $source_preprocess_regex = qr/
+ $source_preprocess_compile_regex
+ | $source_preprocess_no_compile_regex
+ /x;
+# Regex for source files which don't require preprocessing.
+my $source_no_preprocess_compile_regex = qr/
+ # C
+ i
+ # C++
+ | ii
+ # Objective-C
+ | mi
+ # Objective-C++
+ | mii
+ # Fortran
+ | f | for | ftn | f90 | f95 | f03 | f08
+ /x;
+my $source_no_preprocess_no_compile_regex = qr/
+ # Assembly
+ S | sx
+ /x;
+my $source_no_preprocess_regex = qr/
+ $source_no_preprocess_compile_regex
+ | $source_no_preprocess_no_compile_regex
+ /x;
+# Regex for header files which require preprocessing.
+my $header_preprocess_regex = qr/
+ # C, C++, Objective-C, Objective-C++
+ h
+ # C++
+ | hh | H | hp | hxx | hpp | HPP | h\+\+ | tcc
+ /x;
+# Regexps to match files with the given characteristics.
+my $file_no_preprocess_regex = qr/
+ $cc_regex.+?
+ \.(?: $source_no_preprocess_regex)\b
+ /x;
+my $file_preprocess_regex = qr/
+ $cc_regex.+?
+ \.(?: $header_preprocess_regex
+ | $source_preprocess_regex)\b
+ /x;
+my $file_compile_link_regex = qr/
+ $cc_regex.+?
+ \.(?: $source_preprocess_regex
+ | $source_no_preprocess_regex)\b
+ /x;
+my $file_compile_regex = qr/
+ $cc_regex.+?
+ \.(?: $source_preprocess_compile_regex
+ | $source_no_preprocess_compile_regex)\b
+ /x;
+my $file_no_compile_regex = qr/
+ $cc_regex.+
+ \.(?: $source_preprocess_no_compile_regex
+ | $source_no_preprocess_no_compile_regex)\b
+ /x;
+
+# Expected (hardening) flags. All flags are used as regexps.
+my @cflags = (
+ '-g',
+ '-O(?:2|3)',
+);
+my @cflags_format = (
+ '-Wformat',
+ '-Wformat-security',
+ '-Werror=format-security',
+);
+my @cflags_fortify = (
+ # fortify needs at least -O1, but -O2 is recommended anyway
+);
+my @cflags_stack = (
+ '-fstack-protector',
+ '--param=ssp-buffer-size=4',
+);
+my @cflags_pie = (
+ '-fPIE',
+);
+my @cppflags = ();
+my @cppflags_fortify = (
+ '-D_FORTIFY_SOURCE=2',
+);
+my @ldflags = ();
+my @ldflags_relro = (
+ '-Wl,(-z,)?relro',
+);
+my @ldflags_bindnow = (
+ '-Wl,(-z,)?now',
+);
+my @ldflags_pie = (
+ '-fPIE',
+ '-pie',
+);
+# Renaming rules for the output so the regex parts are not visible.
+my %flag_renames = (
+ '-O(?:2|3)' => '-O2',
+ '-Wl,(-z,)?relro' => '-Wl,-z,relro',
+ '-Wl,(-z,)?now' => '-Wl,-z,now',
+);
+
+
# FUNCTIONS
sub error_flags {
error_color(':', 'yellow'),
$line;
}
+sub error_hardening_wrapper {
+ printf "%s%s %s\n",
+ error_color('HARDENING WRAPPER', 'red'),
+ error_color(':', 'yellow'),
+ 'no checks possible, aborting';
+}
sub error_color {
my ($message, $color) = @_;
my ($line, @flags) = @_;
foreach my $flag (@flags) {
- return 1 if $line =~ /\s$flag(?:\s|\\|$)/;
+ return 1 if $line =~ /\s$flag(?:\s|\\)/;
}
return 0;
my @missing_flags = ();
foreach my $flag (@flags) {
- if ($line !~ /\s$flag(?:\s|\\|$)/) {
+ if ($line !~ /\s$flag(?:\s|\\)/) {
push @missing_flags, $flag;
}
}
- if (scalar @missing_flags == 0) {
- return 1;
- }
+ return 1 if scalar @missing_flags == 0;
@{$missing_flags_ref} = @missing_flags;
return 0;
}
sub is_non_verbose_build {
- my ($line, $next_line, $cc_regex, $skip_ref) = @_;
+ my ($line, $next_line, $skip_ref) = @_;
if (not ($line =~ /^checking if you want to see long compiling messages\.\.\. no/
- or $line =~ /^\s*(?:CC|CCLD)\s+(.+?)$/
+ or $line =~ /^\s*\[?(?:CC|CCLD|CXX|CXXLD|LD|LINK)\]?\s+(.+?)$/
or $line =~ /^\s*(?:C|c)ompiling\s+(.+?)(?:\.\.\.)?$/
or $line =~ /^\s*(?:B|b)uilding (?:program|shared library)\s+(.+?)$/
or $line =~ /^\s*\[[\d ]+%\] Building (?:C|CXX) object (.+?)$/)) {
}
-# CONSTANTS/VARIABLES
-
-# Regex to catch compiler commands.
-my $cc_regex = qr/(?:x86_64-linux-gnu-)?(?:(?<!\.)cc|gcc|g\+\+|c\+\+)(?:-[\d.]+)?/;
-# Regex to catch (GCC) compiler warnings.
-my $warning_regex = qr/^(.+?):([0-9]+):[0-9]+: warning: (.+?) \[(.+?)\]$/;
-
-# Expected hardening flags. All flags are used as regexps.
-my @cflags = (
- '-g',
- '-O2',
- '-fstack-protector',
- '--param=ssp-buffer-size=4',
- '-Wformat',
- '-Wformat-security',
- '-Werror=format-security',
-);
-my @cflags_pie = (
- '-fPIE',
-);
-my @cppflags = (
- '-D_FORTIFY_SOURCE=2',
-);
-my @ldflags = (
- '-Wl,(-z,)?relro',
-);
-my @ldflags_pie = (
- '-fPIE',
- '-pie',
-);
-my @ldflags_bindnow = (
- '-Wl,(-z,)?now',
-);
-# All (hardening) flags.
-my @flags = (@cflags, @cflags_pie,
- @cppflags,
- @ldflags, @ldflags_pie, @ldflags_bindnow);
-# Renaming rules for the output so the regex parts are not visible.
-my %flag_renames = (
- '-Wl,(-z,)?relro' => '-Wl,-z,relro',
- '-Wl,(-z,)?now' => '-Wl,-z,now',
-);
-
-
# MAIN
-# Additional hardening options.
-my $pie = 0;
-my $bindnow = 0;
+# Hardening options. Not all architectures support all hardening options.
+my $harden_format = 1;
+my $harden_fortify = 1;
+my $harden_stack = 1;
+my $harden_relro = 1;
+my $harden_bindnow = 0;
+my $harden_pie = 0;
# Parse command line arguments.
-my $option_all = 0;
my $option_help = 0;
my $option_version = 0;
+my $option_all = 0;
+my $option_arch = undef;
+my $option_buildd = 0;
if (not Getopt::Long::GetOptions(
'help|h|?' => \$option_help,
'version' => \$option_version,
- 'pie' => \$pie,
- 'bindnow' => \$bindnow,
+ # Hardening options.
+ 'pie' => \$harden_pie,
+ 'bindnow' => \$harden_bindnow,
'all' => \$option_all,
+ # Misc.
+ 'arch' => \$option_arch,
+ 'buildd' => \$option_buildd,
)) {
require Pod::Usage;
Pod::Usage::pod2usage(2);
}
if ($option_all) {
- $pie = 1;
- $bindnow = 1;
+ $harden_pie = 1;
+ $harden_bindnow = 1;
}
# Final exit code.
my $start = 0;
my $continuation = 0;
+my $complete_line = undef;
while (my $line = <>) {
- # We skip over unimportant lines at the beginning to prevent false
- # positives.
+ # dpkg-buildflags only provides hardening flags since 1.16.1, don't check
+ # for hardening flags in buildd mode if an older dpkg-dev is used. Default
+ # flags (-g -O2) are still checked.
+ #
+ # Packages which were built before 1.16.1 but used their own hardening
+ # flags are not checked.
+ if ($option_buildd and not $start
+ and $line =~ /^Toolchain package versions: /) {
+ require Dpkg::Version;
+ if ($line !~ /dpkg-dev_(\S+)/
+ or Dpkg::Version::version_compare($1, '1.16.1') < 0) {
+ $harden_format = 0;
+ $harden_fortify = 0;
+ $harden_stack = 0;
+ $harden_relro = 0;
+ $harden_bindnow = 0;
+ $harden_pie = 0;
+ }
+ }
+
+ # If hardening wrapper is used (wraps calls to gcc and adds hardening
+ # flags automatically) we can't perform any checks, abort.
+ if (not $start and $line =~ /^Build-Depends: .*\bhardening-wrapper\b/) {
+ error_hardening_wrapper();
+ $exit |= 1 << 4;
+ exit $exit;
+ }
+
+ # We skip over unimportant lines at the beginning of the log to prevent
+ # false positives.
$start = 1 if $line =~ /^dpkg-buildpackage:/;
next if not $start;
+ # 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.
+ last if $line =~ /^Build finished at \d{8}-\d{4}$/;
+
+ # Detect architecture automatically unless overridden.
+ if (not $option_arch
+ and $line =~ /^dpkg-buildpackage: host architecture (.+)$/) {
+ $option_arch = $1;
+ }
# Ignore compiler warnings for now.
next if $line =~ /$warning_regex/;
+ # Remove all ANSI color sequences which are sometimes used in non-verbose
+ # builds.
+ $line = Term::ANSIColor::colorstrip($line);
+ # Also strip '\0xf' (delete previous character), used by Elinks' build
+ # system.
+ $line =~ s/\x0f//g;
+ # And "ESC(B" which seems to be used on armhf and hurd (not sure what it
+ # does).
+ $line =~ s/\033\(B//g;
+
# Check if this line indicates a non verbose build.
my $non_verbose = is_non_verbose_build($line);
# One line may contain multiple commands (";"). Treat each one as single
- # line.
- my @line = split /(?<!\\);/, $line;
+ # line. parse_line() is slow, only use it when necessary.
+ my @line = (not $line =~ /;/)
+ ? ($line)
+ : Text::ParseWords::parse_line(';', 1, $line);
foreach $line (@line) {
# Add newline, drop all other whitespace at the end of a line.
$line =~ s/\s+$//;
# Join lines, but leave the "\" in place so it's clear where the
# original line break was.
- chomp $input[-1];
- $input[-1] .= ' ' . $line;
+ chomp $complete_line;
+ $complete_line .= ' ' . $line;
+ }
+ # Line continuation, line ends with "\".
+ if ($line =~ /\\\s*$/) {
+ $continuation = 1;
+ # Start line continuation.
+ if (not defined $complete_line) {
+ $complete_line = $line;
+ }
+ next;
+ }
+
+ if (not $continuation) {
+ # Use the complete line if a line continuation occurred.
+ if (defined $complete_line) {
+ $line = $complete_line;
+ $complete_line = undef;
+ }
- } else {
# Ignore lines with no compiler commands.
next if $line !~ /\b$cc_regex(?:\s|\\)/ and not $non_verbose;
# Ignore false positives.
#
# `./configure` output.
- next if not $non_verbose and $line =~ /^checking /;
+ next if not $non_verbose
+ and $line =~ /^(?:checking|(?:C|c)onfigure:) /;
+ next if $line =~ /^\s*(?:Host\s+)?(?:C\s+)?
+ (?:C|c)ompiler[\s.]*:?\s+
+ $cc_regex
+ (?:\s-std=[a-z0-9:+]+)?\s*$
+ /x
+ or $line =~ /^\s*(?:- )?(?:HOST_)?(?:CC|CXX)\s*=\s*$cc_regex\s*$/
+ or $line =~ /^\s*-- Check for working (?:C|CXX) compiler: /
+ or $line =~ /^\s*(?:echo )?Using [A-Z_]+\s*=\s*/;
+
+ # Check if additional hardening options were used. Used to ensure
+ # they are used for the complete build.
+ $harden_pie = 1 if any_flags_used($line, @cflags_pie, @ldflags_pie);
+ $harden_bindnow = 1 if any_flags_used($line, @ldflags_bindnow);
push @input, $line;
}
-
- # Line continuation, line ends with "\".
- if ($line =~ /\\\s*$/) {
- $continuation = 1;
- }
}
}
exit $exit;
}
-# Check if additional hardening options were used. Used to ensure they are
-# used for the complete build.
-foreach my $line (@input) {
- $pie = 1 if any_flags_used($line, @cflags_pie, @ldflags_pie);
- $bindnow = 1 if any_flags_used($line, @ldflags_bindnow);
+# Option or auto detected.
+if ($option_arch) {
+ # The following was partially copied from dpkg-dev 1.16.1.2
+ # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()),
+ # copyright Raphaƫl Hertzog <hertzog@debian.org>, Kees Cook
+ # <kees@debian.org>, Canonical, Ltd. licensed under GPL version 2 or
+ # later. Keep it in sync.
+
+ require Dpkg::Arch;
+ my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($option_arch);
+
+ # Disable unsupported hardening options.
+ if ($cpu =~ /^(ia64|alpha|mips|mipsel|hppa)$/ or $option_arch eq 'arm') {
+ $harden_stack = 0;
+ }
+ if ($cpu =~ /^(ia64|hppa|avr32)$/) {
+ $harden_relro = 0;
+ $harden_bindnow = 0;
+ }
}
-if ($pie) {
+# Check the specified hardening options, same order as dpkg-buildflags.
+if ($harden_pie) {
@cflags = (@cflags, @cflags_pie);
@ldflags = (@ldflags, @ldflags_pie);
}
-if ($bindnow) {
+if ($harden_stack) {
+ @cflags = (@cflags, @cflags_stack);
+}
+if ($harden_fortify) {
+ @cflags = (@cflags, @cflags_fortify);
+ @cppflags = (@cppflags, @cppflags_fortify);
+}
+if ($harden_format) {
+ @cflags = (@cflags, @cflags_format);
+}
+if ($harden_relro) {
+ @ldflags = (@ldflags, @ldflags_relro);
+}
+if ($harden_bindnow) {
@ldflags = (@ldflags, @ldflags_bindnow);
}
my $line = $input[$i];
my $skip = 0;
- if (is_non_verbose_build($line, $input[$i + 1], $cc_regex, \$skip)) {
+ if (is_non_verbose_build($line, $input[$i + 1], \$skip)) {
error_non_verbose_build($line);
$exit |= 1 << 2;
next;
# Even if it's a verbose build, we might have to skip this line.
next if $skip;
- # Ignore false positives.
- #
- # ./configure summary.
- next if $line =~ /^\s*(?:C|c)ompiler[\s.]*:\s+$cc_regex(?:\s-std=[a-z0-9:+]+)?\s*$/
- or $line =~ /^\s*- (?:CC|CXX)\s*=\s*$cc_regex\s*$/
- or $line =~ /^\s*-- Check for working (?:C|CXX) compiler: /;
-
- # Is this a compiler or linker command?
- my $compiler = 1;
- my $linker = 0;
-
- # Linker commands.
- if ($line =~ m{\s-o # -o
- [\s\\]*\s+ # possible line continuation
- (?:[/.A-Za-z0-9~_-]+/)? # path to file
- [A-Za-z0-9~_-]+ # binary name (no dots!)
- (?:[0-9.]*\.so[0-9.]*[a-z]? # library (including version)
- |\.la)?
- (?:\s|\\|$) # end of file name
- }x
- or $line =~ /^libtool: link: /
- or $line =~ m{\s*/bin/bash .+?libtool\s+(.+?\s+)?--mode=(re)?link}) {
- $compiler = 0;
- $linker = 1;
+ # Skip unnecessary tests when only preprocessing.
+ my $flag_preprocess = 0;
+
+ my $preprocess = 0;
+ my $compile = 0;
+ my $link = 0;
+
+ # Preprocess, compile, assemble.
+ if ($line =~ /$cc_regex.*?\s(-E|-S|-c)\b/) {
+ $preprocess = 1;
+ $flag_preprocess = 1 if $1 eq '-E';
+ $compile = 1 if $1 eq '-S' or $1 eq '-c';
+ # Otherwise assume we are linking.
+ } else {
+ $link = 1;
+ }
+
+ # These file types don't require preprocessing.
+ if ($line =~ /$file_no_preprocess_regex/) {
+ $preprocess = 0;
+ }
+ # These file types require preprocessing.
+ if ($line =~ /$file_preprocess_regex/) {
+ $preprocess = 1;
}
# If there are source files then it's compiling/linking in one step and we
- # must check both.
- if ($line =~ /\.(?:c|cc|cpp)\b/) {
- $compiler = 1;
+ # must check both. We only check for source files here, because header
+ # files cause too many false positives.
+ if (not $flag_preprocess and $line =~ /$file_compile_link_regex/) {
+ # Assembly files don't need CFLAGS.
+ if (not $line =~ /$file_compile_regex/
+ and $line =~ /$file_no_compile_regex/) {
+ $compile = 0;
+ # But the rest does.
+ } else {
+ $compile = 1;
+ }
}
# Check hardening flags.
my @missing;
- if ($compiler and not all_flags_used($line, \@missing, @cflags)
+ if ($compile and not all_flags_used($line, \@missing, @cflags)
# Libraries linked with -fPIC don't have to (and can't) be linked
# with -fPIE as well. It's no error if only PIE flags are missing.
- and not pic_pie_conflict($line, $pie, \@missing, @cflags_pie)) {
+ and not pic_pie_conflict($line, $harden_pie, \@missing, @cflags_pie)
+ # Assume dpkg-buildflags returns the correct flags.
+ and not $line =~ /`dpkg-buildflags --get (?:CFLAGS|CXXFLAGS)`/) {
error_flags('CFLAGS missing', \@missing, \%flag_renames, $line);
$exit |= 1 << 3;
}
- if ($compiler and not all_flags_used($line, \@missing, @cppflags)) {
+ if ($preprocess and not all_flags_used($line, \@missing, @cppflags)
+ # Assume dpkg-buildflags returns the correct flags.
+ and not $line =~ /`dpkg-buildflags --get CPPFLAGS`/) {
error_flags('CPPFLAGS missing', \@missing, \%flag_renames, $line);
$exit |= 1 << 3;
}
- if ($linker and not all_flags_used($line, \@missing, @ldflags)
+ if ($link and not all_flags_used($line, \@missing, @ldflags)
# Same here, -fPIC conflicts with -fPIE.
- and not pic_pie_conflict($line, $pie, \@missing, @ldflags_pie)) {
+ and not pic_pie_conflict($line, $harden_pie, \@missing, @ldflags_pie)
+ # Assume dpkg-buildflags returns the correct flags.
+ and not $line =~ /`dpkg-buildflags --get LDFLAGS`/) {
error_flags('LDFLAGS missing', \@missing, \%flag_renames, $line);
$exit |= 1 << 3;
}
--pie force +pie check
--bindnow force +bindbow check
--all force +all (+pie, +bindnow) check
+ --arch set architecture (autodetected)
+ --buildd parser mode for buildds
=head1 DESCRIPTION
Force check for all +all (+pie, +bindnow) hardening flags. By default it's
auto detected.
+=item B<--arch>
+
+Set the specific architecture (e.g. amd64, armel, etc.), automatically
+disables hardening flags not available on this architecture. Is detected
+automatically if dpkg-buildpackage is used.
+
+=item B<--buildd>
+
+Special mode for buildds when automatically parsing log files. The following
+changes are in effect:
+
+=over 2
+
+=item
+
+Don't check hardening flags in old log files (if dpkg-dev << 1.16.1 is
+detected).
+
=back
-Auto detection only works if at least one command uses the required hardening
-flag (e.g. -fPIE). Then it's required for all other commands as well.
+=back
+
+Auto detection for B<--pie> and B<--bindnow> only works if at least one
+command uses the required hardening flag (e.g. -fPIE). Then it's required for
+all other commands as well.
=head1 EXIT STATUS
Missing hardening flags.
+=item B<16>
+
+Hardening wrapper detected, no tests performed.
+
=back
=head1 AUTHOR