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# files/symbolic-links -- lintian check script -*- perl -*-
# Copyright (C) 1998 Christian Schwarz and Richard Braakman
#
# 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
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, you can find it on the World Wide
# Web at https://www.gnu.org/copyleft/gpl.html, or write to the Free
# Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
# MA 02110-1301, USA.
package Lintian::Check::Files::SymbolicLinks;
use v5.20;
use warnings;
use utf8;
use Const::Fast;
use Moo;
use namespace::clean;
with 'Lintian::Check';
const my $SLASH => q{/};
const my $DOT => q{.};
const my $DOUBLE_DOT => q{..};
const my $VERTICAL_BAR => q{|};
const my $ARROW => q{->};
# an OR (|) regex of all compressed extension
has COMPRESS_FILE_EXTENSIONS_OR_ALL => (
is => 'rw',
lazy => 1,
default => sub {
my ($self) = @_;
my $COMPRESS_FILE_EXTENSIONS
= $self->data->load('files/compressed-file-extensions',qr/\s+/);
my $text = join($VERTICAL_BAR,
(map { quotemeta } $COMPRESS_FILE_EXTENSIONS->all));
return qr/$text/;
}
);
sub visit_patched_files {
my ($self, $item) = @_;
return
unless $item->is_symlink;
# absolute links cannot be resolved
if ($item->link =~ m{^/}) {
# allow /dev/null link target for masked systemd service files
$self->pointed_hint('absolute-symbolic-link-target-in-source',
$item->pointer, $item->link)
unless $item->link eq '/dev/null';
}
# some relative links cannot be resolved inside the source
$self->pointed_hint('wayward-symbolic-link-target-in-source',
$item->pointer, $item->link)
unless defined $_->link_normalized || $item->link =~ m{^/};
return;
}
sub is_tmp_path {
my ($path) = @_;
return 1
if $path =~ m{^tmp/.}
|| $path =~ m{^(?:var|usr)/tmp/.}
|| $path =~ m{^/dev/shm/};
return 0;
}
sub visit_installed_files {
my ($self, $item) = @_;
return
unless $item->is_symlink;
my $mylink = $item->link;
$self->pointed_hint('symlink-has-double-slash', $item->pointer,$item->link)
if $mylink =~ s{//+}{/}g;
$self->pointed_hint('symlink-ends-with-slash', $item->pointer, $item->link)
if $mylink =~ s{(.)/$}{$1};
# determine top-level directory of file
$item->name =~ m{^/?([^/]*)};
my $filetop = $1;
if ($mylink =~ m{^/([^/]*)}) {
my $flinkname = substr($mylink,1);
# absolute link, including link to /
# determine top-level directory of link
my $linktop = $1;
if ($self->processable->type ne 'udeb' and $filetop eq $linktop) {
# absolute links within one toplevel directory are _not_ ok!
$self->pointed_hint('absolute-symlink-in-top-level-folder',
$item->pointer, $item->link);
}
my $BUILD_PATH_REGEX
= $self->data->load('files/build-path-regex',qr/~~~~~/);
for my $pattern ($BUILD_PATH_REGEX->all) {
$self->pointed_hint('symlink-target-in-build-tree',
$item->pointer, $mylink)
if $flinkname =~ m{$pattern}xms;
}
$self->pointed_hint('symlink-target-in-tmp', $item->pointer,$mylink)
if is_tmp_path($flinkname);
# Any other case is already definitely non-recursive
$self->pointed_hint('symlink-is-self-recursive', $item->pointer,
$item->link)
if $mylink eq $SLASH;
} else {
# relative link, we can assume from here that the link
# starts nor ends with /
my @filecomponents = split(m{/}, $item->name);
# chop off the name of the symlink
pop @filecomponents;
my @linkcomponents = split(m{/}, $mylink);
# handle `../' at beginning of $item->link
my ($lastpop, $linkcomponent);
while ($linkcomponent = shift @linkcomponents) {
if ($linkcomponent eq $DOT) {
$self->pointed_hint('symlink-contains-spurious-segments',
$item->pointer, $item->link)
unless $mylink eq $DOT;
next;
}
last if $linkcomponent ne $DOUBLE_DOT;
if (@filecomponents) {
$lastpop = pop @filecomponents;
} else {
$self->pointed_hint('symlink-has-too-many-up-segments',
$item->pointer, $item->link);
goto NEXT_LINK;
}
}
if (!defined $linkcomponent) {
# After stripping all starting .. components, nothing left
$self->pointed_hint('symlink-is-self-recursive', $item->pointer,
$item->link);
}
# does the link go up and then down into the same
# directory? (lastpop indicates there was a backref
# at all, no linkcomponent means the symlink doesn't
# get up anymore)
if ( defined $lastpop
&& defined $linkcomponent
&& $linkcomponent eq $lastpop) {
$self->pointed_hint('lengthy-symlink', $item->pointer,$item->link);
}
unless (@filecomponents) {
# we've reached the root directory
if ( ($self->processable->type ne 'udeb')
&& (!defined $linkcomponent)
|| ($filetop ne $linkcomponent)) {
# relative link into other toplevel directory.
# this hits a relative symbolic link in the root too.
$self->pointed_hint('relative-symlink', $item->pointer,
$item->link);
}
}
# check additional segments for mistakes like `foo/../bar/'
foreach (@linkcomponents) {
if ($_ eq $DOUBLE_DOT || $_ eq $DOT) {
$self->pointed_hint('symlink-contains-spurious-segments',
$item->pointer, $item->link);
last;
}
}
}
NEXT_LINK:
my $pattern = $self->COMPRESS_FILE_EXTENSIONS_OR_ALL;
# symlink pointing to a compressed file
if ($item->link =~ qr{ [.] ($pattern) \s* $}x) {
my $extension = $1;
# symlink has correct extension?
$self->pointed_hint('compressed-symlink-with-wrong-ext',
$item->pointer, $item->link)
unless $item->name =~ qr{[.]$extension\s*$};
}
return;
}
1;
# Local Variables:
# indent-tabs-mode: nil
# cperl-indent-level: 4
# End:
# vim: syntax=perl sw=4 sts=4 sr et
|
