X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=bin%2Fblhc;h=f7988b5d1e5914a9b414ab504908cf506a19c67a;hb=516e39a71f9a8f6e0d01fd13c40e4db0557de8df;hp=383fcc15f06b0d0a3ea750d6104e4d9357fbd023;hpb=2475b608a1edcc1a00d8046e32b55472dd81684f;p=blhc%2Fblhc.git diff --git a/bin/blhc b/bin/blhc index 383fcc1..f7988b5 100755 --- a/bin/blhc +++ b/bin/blhc @@ -23,10 +23,141 @@ use warnings; 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)?-)? + (? '-O2', + '-Wl,(-z,)?relro' => '-Wl,-z,relro', + '-Wl,(-z,)?now' => '-Wl,-z,now', +); + +# Use colored (ANSI) output? +my $option_color; + + # FUNCTIONS sub error_flags { @@ -44,11 +175,24 @@ sub error_flags { error_color($message, 'red'), $flags, error_color(':', 'yellow'), $line; } +sub error_non_verbose_build { + my ($line) = @_; + + printf "%s%s %s", + error_color('NONVERBOSE BUILD', 'red'), + 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, $color) = @_; - # Use colors when writing to a terminal. - if (-t STDOUT) { + if ($option_color) { return Term::ANSIColor::colored($message, $color); } else { return $message; @@ -59,7 +203,7 @@ sub any_flags_used { my ($line, @flags) = @_; foreach my $flag (@flags) { - return 1 if $line =~ /\s$flag(\s|\\|$)/; + return 1 if $line =~ /\s$flag(?:\s|\\)/; } return 0; @@ -69,14 +213,12 @@ sub all_flags_used { 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; @@ -87,7 +229,7 @@ sub pic_pie_conflict { my ($line, $pie, $missing_flags_ref, @flags_pie) = @_; return 0 if not $pie; - return 0 if not any_flags_used($line, ('-fPIC')); + return 0 if not any_flags_used($line, ('-fPIC', '-fpic')); my %flags = map { $_ => 1 } @flags_pie; @@ -104,65 +246,74 @@ sub pic_pie_conflict { return scalar @result == 0; } +sub is_non_verbose_build { + my ($line, $next_line, $skip_ref) = @_; -# CONSTANTS/VARIABLES + if (not ($line =~ /^checking if you want to see long compiling messages\.\.\. no/ + 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 (.+?)$/)) { + return 0; + } -# Regex to catch (GCC) compiler warnings. -my $warning_regex = qr/^(.+?):([0-9]+):[0-9]+: warning: (.+?) \[(.+?)\]$/; + my $file = $1; -# 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', -); + # On the first pass we only check if this line is verbose or not. + return 1 if not defined $next_line; + + # Second pass, we have access to the next line. + ${$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. + if (defined $file) { + # Get filename, we can't use the complete path as only parts of it are + # used in the real compiler command. + $file =~ m{/([a-zA-Z0-9._-]+)$}; + $file = $1; + + if ($next_line =~ /\Q$file\E/ and $next_line =~ /$cc_regex/) { + # We still have to skip the current line as it doesn't contain any + # compiler commands. + ${$skip_ref} = 1; + return 0; + } + } + + return 1; +} # 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; + $option_color = 0; if (not Getopt::Long::GetOptions( 'help|h|?' => \$option_help, 'version' => \$option_version, - 'pie' => \$pie, - 'bindnow' => \$bindnow, + # Hardening options. + 'pie' => \$harden_pie, + 'bindnow' => \$harden_bindnow, 'all' => \$option_all, + # Misc. + 'color' => \$option_color, + 'arch' => \$option_arch, + 'buildd' => \$option_buildd, )) { require Pod::Usage; Pod::Usage::pod2usage(2); @@ -191,8 +342,8 @@ along with this program. If not, see . } if ($option_all) { - $pie = 1; - $bindnow = 1; + $harden_pie = 1; + $harden_bindnow = 1; } # Final exit code. @@ -201,14 +352,74 @@ my $exit = 0; # Input lines, contain only the lines with compiler commands. my @input = (); +my $start = 0; my $continuation = 0; +my $complete_line = undef; while (my $line = <>) { + # dpkg-buildflags only provides hardening flags since 1.16.1, don't check + # for hardening flags in buildd mode if an older dpkg-dev is used. Default + # flags (-g -O2) are still checked. + # + # Packages which were built before 1.16.1 but used their own hardening + # flags are not checked. + if ($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 /(?) { # 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|gcc|g\+\+|c\+\+)(\s|\\)/; + next if $line !~ /\b$cc_regex(?:\s|\\)/ and not $non_verbose; # Ignore false positives. # # `./configure` output. - if ($line =~ /^checking /) { - next; - } + 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; - } } } @@ -249,59 +483,125 @@ if (scalar @input == 0) { 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 ($option_arch) { + # The following was partially copied from dpkg-dev 1.16.1.2 + # (/usr/share/perl5/Dpkg/Vendor/Debian.pm, add_hardening_flags()), + # copyright Raphaël Hertzog , Kees Cook + # , Canonical, Ltd. licensed under GPL version 2 or + # later. Keep it in sync. + + require Dpkg::Arch; + my ($abi, $os, $cpu) = Dpkg::Arch::debarch_to_debtriplet($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); } -foreach my $line (@input) { - # Is this a compiler or linker command? - my $compiler = 1; - my $linker = 0; - - # Linker commands. - if ($line =~ /\s-l[A-Za-z0-9.-]+(\s|\\|$)/ - or $line =~ m{\s-o ([A-Za-z0-9_/.-]+/)?[A-Za-z0-9_-]+(\.so([0-9.])*|\.la)?(\s|\\|\$)} - or $line =~ /^libtool: link: / - or $line =~ m{\s*/bin/bash .+?libtool\s+(.+?\s+)?--mode=(re)?link}) { - $compiler = 0; - $linker = 1; +for (my $i = 0; $i < scalar @input; $i++) { + my $line = $input[$i]; + + my $skip = 0; + if (is_non_verbose_build($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; + + # 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 << 2; + $exit |= 1 << 3; } - if ($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 << 2; + $exit |= 1 << 3; } - if ($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 << 2; + $exit |= 1 << 3; } } @@ -325,6 +625,9 @@ B [--pie] [--bindnow] [--all] --pie force +pie check --bindnow force +bindbow check --all force +all (+pie, +bindnow) check + --arch set architecture (autodetected) + --buildd parser mode for buildds + --color use colored output =head1 DESCRIPTION @@ -356,10 +659,35 @@ Force check for all +bindnow hardening flags. By default it's auto detected. 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. +=item B<--color> + +Use colored (ANSI) output for warning messages. + +=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 @@ -382,8 +710,16 @@ Invalid arguments/options given to blhc. =item B<4> +Non verbose build. + +=item B<8> + Missing hardening flags. +=item B<16> + +Hardening wrapper detected, no tests performed. + =back =head1 AUTHOR