Merge branch 'master' into debian-jessie-backports

[git.ikiwiki.info.git] / IkiWiki / Plugin / img.pm

diff --git a/IkiWiki/Plugin/img.pm b/IkiWiki/Plugin/img.pm
index ae681f9e65ca975f6dfedcfd87b0b80307975613..740c44f96045e19e5ed4f79dcca8db4369feeae6 100644 (file)
--- a/IkiWiki/Plugin/img.pm
+++ b/IkiWiki/Plugin/img.pm
@@ -21,6 +21,28 @@ sub getsetup () {
                        rebuild => undef,
                        section => "widget",
                },
                        rebuild => undef,
                        section => "widget",
                },

+               img_allowed_formats => {
+                       type => "string",
+                       default => [qw(jpeg png gif svg)],
+                       description => "Image formats to process (jpeg, png, gif, svg, pdf or 'everything' to accept all)",
+                       # ImageMagick has had arbitrary code execution flaws,
+                       # and the whole delegates mechanism is scary from
+                       # that perspective
+                       safe => 0,
+                       rebuild => 0,
+               },
+}
+
+sub allowed {
+       my $format = shift;
+       my $allowed = $config{img_allowed_formats};
+       $allowed = ['jpeg', 'png', 'gif', 'svg'] unless defined $allowed && @$allowed;
+
+       foreach my $a (@$allowed) {
+               return 1 if lc($a) eq $format || lc($a) eq 'everything';
+       }
+
+       return 0;

 }
 
 sub preprocess (@) {
 }
 
 sub preprocess (@) {


@@ -64,53 +86,129 @@ sub preprocess (@) {
 
        my $dir = $params{page};
        my $base = IkiWiki::basename($file);
 
        my $dir = $params{page};
        my $base = IkiWiki::basename($file);

-       my $issvg = $base=~s/\.svg$/.png/i;
+       my $extension;
+       my $format;
+
+       if ($base =~ m/\.([a-z0-9]+)$/is) {
+               $extension = $1;
+       }
+       else {
+               error gettext("Unable to detect image type from extension");
+       }
+
+       # Never interpret well-known file extensions as any other format,
+       # in case the wiki configuration unwisely allows attaching
+       # arbitrary files named *.jpg, etc.
+       my $magic;
+       my $offset = 0;
+       open(my $in, '<', $srcfile) or error sprintf(gettext("failed to read %s: %s"), $file, $!);
+       binmode($in);
+
+       if ($extension =~ m/^(jpeg|jpg)$/is) {
+               $format = 'jpeg';
+               $magic = "\377\330\377";
+       }
+       elsif ($extension =~ m/^(png)$/is) {
+               $format = 'png';
+               $magic = "\211PNG\r\n\032\n";
+       }
+       elsif ($extension =~ m/^(gif)$/is) {
+               $format = 'gif';
+               $magic = "GIF8";
+       }
+       elsif ($extension =~ m/^(svg)$/is) {
+               $format = 'svg';
+       }
+       elsif ($extension =~ m/^(pdf)$/is) {
+               $format = 'pdf';
+               $magic = "%PDF-";
+       }
+       else {
+               # allow ImageMagick to auto-detect (potentially dangerous)
+               $format = '';
+       }
+
+       error sprintf(gettext("%s image processing disabled in img_allowed_formats configuration"), $format ? $format : "\"$extension\"") unless allowed($format ? $format : "everything");
+
+       # Try harder to protect ImageMagick from itself
+       if (defined $magic) {
+               my $content;
+               read($in, $content, length $magic) or error sprintf(gettext("failed to read %s: %s"), $file, $!);
+               if ($magic ne $content) {
+                       error sprintf(gettext("\"%s\" does not seem to be a valid %s file"), $file, $format);
+               }
+       }
+

        my $ispdf = $base=~s/\.pdf$/.png/i;
        my $ispdf = $base=~s/\.pdf$/.png/i;

+       my $pagenumber = exists($params{pagenumber}) ? int($params{pagenumber}) : 0;
+       if ($pagenumber != 0) {
+               $base = "p$pagenumber-$base";
+       }

 
 

-       eval q{use Image::Magick};
-       error gettext("Image::Magick is not installed") if $@;
-       my $im = Image::Magick->new();

        my $imglink;
        my $imglink;

-       my $r = $im->Read($srcfile);
-       error sprintf(gettext("failed to read %s: %s"), $file, $r) if $r;
-       
+       my $imgdatalink;

        my ($dwidth, $dheight);
 
        my ($dwidth, $dheight);
 

+       my ($w, $h);

        if ($params{size} ne 'full') {
        if ($params{size} ne 'full') {

-               my ($w, $h) = ($params{size} =~ /^(\d*)x(\d*)$/);
-               error sprintf(gettext('wrong size format "%s" (should be WxH)'), $params{size})
-                       unless (defined $w && defined $h &&
-                               (length $w || length $h));
-               
-               if ((length $w && $w > $im->Get("width")) ||
-                   (length $h && $h > $im->Get("height"))) {
-                       # resizing larger
-                       $imglink = $file;
+               ($w, $h) = ($params{size} =~ /^(\d*)x(\d*)$/);
+       }

 
 

-                       # don't generate larger image, just set display size
-                       if (length $w && length $h) {
-                               ($dwidth, $dheight)=($w, $h);
-                       }
-                       # avoid division by zero on 0x0 image
-                       elsif ($im->Get("width") == 0 || $im->Get("height") == 0) {
+       if ($format eq 'svg') {
+               # svg images are not scaled using ImageMagick because the
+               # pipeline is complex. Instead, the image size is simply
+               # set to the provided values.
+               #
+               # Aspect ratio will be preserved automatically when
+               # only a width or only a height is specified.
+               # When both are specified, aspect ratio will not be
+               # preserved.
+               $imglink = $file;
+               $dwidth = $w if length $w;
+               $dheight = $h if length $h;
+       }
+       else {
+               eval q{use Image::Magick};
+               error gettext("Image::Magick is not installed") if $@;
+               my $im = Image::Magick->new();
+               my $r = $im->Read("$format:$srcfile\[$pagenumber]");
+               error sprintf(gettext("failed to read %s: %s"), $file, $r) if $r;
+
+               if (! defined $im->Get("width") || ! defined $im->Get("height")) {
+                       error sprintf(gettext("failed to get dimensions of %s"), $file);
+               }
+
+               if (! length $w && ! length $h) {
+                       $dwidth = $im->Get("width");
+                       $dheight = $im->Get("height");
+               } else {
+                       error sprintf(gettext('wrong size format "%s" (should be WxH)'), $params{size})
+                               unless (defined $w && defined $h &&
+                                       (length $w || length $h));
+
+                       if ($im->Get("width") == 0 || $im->Get("height") == 0) {

                                ($dwidth, $dheight)=(0, 0);
                                ($dwidth, $dheight)=(0, 0);

-                       }
-                       # calculate unspecified size from the other one, preserving
-                       # aspect ratio
-                       elsif (length $w) {
-                               $dwidth=$w;
-                               $dheight=$w / $im->Get("width") * $im->Get("height");
-                       }
-                       elsif (length $h) {
+                       } elsif (! length $w || (length $h && $im->Get("height")*$w > $h * $im->Get("width"))) {
+                               # using height because only height is given or ...
+                               # because original image is more portrait than $w/$h
+                               # ... slimness of $im > $h/w
+                               # ... $im->Get("height")/$im->Get("width") > $h/$w
+                               # ... $im->Get("height")*$w > $h * $im->Get("width")
+

                                $dheight=$h;
                                $dwidth=$h / $im->Get("height") * $im->Get("width");
                                $dheight=$h;
                                $dwidth=$h / $im->Get("height") * $im->Get("width");

+                       } else { # (! length $h) or $w is what determines the resized size
+                               $dwidth=$w;
+                               $dheight=$w / $im->Get("width") * $im->Get("height");

                        }
                }
                        }
                }

-               else {
-                       # resizing smaller
-                       my $outfile = "$config{destdir}/$dir/${w}x${h}-$base";
-                       $imglink = "$dir/${w}x${h}-$base";
-               
+
+               if ($dwidth < $im->Get("width") || $ispdf) {
+                       # resize down, or resize to pixels at all
+
+                       my $outfile = "$config{destdir}/$dir/$params{size}-$base";
+                       $imglink = "$dir/$params{size}-$base";
+

                        will_render($params{page}, $imglink);
 
                        if (-e $outfile && (-M $srcfile >= -M $outfile)) {
                        will_render($params{page}, $imglink);
 
                        if (-e $outfile && (-M $srcfile >= -M $outfile)) {


@@ -119,45 +217,40 @@ sub preprocess (@) {
                                error sprintf(gettext("failed to read %s: %s"), $outfile, $r) if $r;
                        }
                        else {
                                error sprintf(gettext("failed to read %s: %s"), $outfile, $r) if $r;
                        }
                        else {

-                               $r = $im->Resize(geometry => "${w}x${h}");
+                               $r = $im->Resize(geometry => "${dwidth}x${dheight}");

                                error sprintf(gettext("failed to resize: %s"), $r) if $r;
 
                                error sprintf(gettext("failed to resize: %s"), $r) if $r;
 

+                               $im->set($ispdf ? (magick => 'png') : ());
+                               my @blob = $im->ImageToBlob();

                                # don't actually write resized file in preview mode;
                                # rely on width and height settings
                                if (! $params{preview}) {
                                # don't actually write resized file in preview mode;
                                # rely on width and height settings
                                if (! $params{preview}) {

-                                       $im->set(($issvg || $ispdf) ? (magick => 'png') : ());
-                                       my @blob = $im->ImageToBlob();

                                        writefile($imglink, $config{destdir}, $blob[0], 1);
                                }
                                else {
                                        writefile($imglink, $config{destdir}, $blob[0], 1);
                                }
                                else {

-                                       $imglink = $file;
+                                       eval q{use MIME::Base64};
+                                       error($@) if $@;
+                                       $imgdatalink = "data:image/".$im->Get("magick").";base64,".encode_base64($blob[0]);

                                }
                        }
 
                                }
                        }
 

-                       # always get the true size of the resized image
-                       $dwidth  = $im->Get("width"); 
+                       # always get the true size of the resized image (it could be
+                       # that imagemagick did its calculations differently)
+                       $dwidth  = $im->Get("width");

                        $dheight = $im->Get("height");
                        $dheight = $im->Get("height");

+               } else {
+                       $imglink = $file;
+               }
+
+               if (! defined($dwidth) || ! defined($dheight)) {
+                       error sprintf(gettext("failed to determine size of image %s"), $file)

                }
                }

-       }
-       else {
-               $imglink = $file;
-               $dwidth = $im->Get("width");
-               $dheight = $im->Get("height");
-       }
-       
-       if (! defined($dwidth) || ! defined($dheight)) {
-               error sprintf(gettext("failed to determine size of image %s"), $file)

        }
 
        my ($fileurl, $imgurl);
        }
 
        my ($fileurl, $imgurl);

-       if (! $params{preview}) {
-               $fileurl=urlto($file, $params{destpage});
-               $imgurl=urlto($imglink, $params{destpage});
-       }
-       else {
-               $fileurl=urlto($file);
-               $imgurl=urlto($imglink);
-       }
+       my $urltobase = $params{preview} ? undef : $params{destpage};
+       $fileurl=urlto($file, $urltobase);
+       $imgurl=$imgdatalink ? $imgdatalink : urlto($imglink, $urltobase);

 
        if (! exists $params{class}) {
                $params{class}="img";
 
        if (! exists $params{class}) {
                $params{class}="img";


@@ -170,10 +263,10 @@ sub preprocess (@) {
                }
        }
        
                }
        }
        

-       my $imgtag='<img src="'.$imgurl.
-               '" width="'.$dwidth.
-               '" height="'.$dheight.'"'.
-               $attrs.
+       my $imgtag='<img src="'.$imgurl.'"';
+       $imgtag.=' width="'.$dwidth.'"' if defined $dwidth;
+       $imgtag.=' height="'.$dheight.'"' if defined $dheight;
+       $imgtag.= $attrs.

                (exists $params{align} && ! exists $params{caption} ? ' align="'.$params{align}.'"' : '').
                ' />';
 
                (exists $params{align} && ! exists $params{caption} ? ' align="'.$params{align}.'"' : '').
                ' />';