[pve-devel] [PATCH storage 3/9] plugin: dir: handle ova files for import

[Dominik Csapak <d.csapak@proxmox.com>]

since we want to handle ova files (which are only ovf+vmdks bundled in a
tar file) for import, add code that handles that.

we introduce a valid volname for files contained in ovas like this:

 storage:import/archive.ova/disk-1.vmdk

by basically treating the last part of the path as the name for the
contained disk we want.

we then provide 3 functions to use for that:

* copy_needs_extraction: determines from the given volid (like above) if
  that needs extraction to copy it, currently only 'import' vtype +
  defined format returns true here (if we have more options in the
  future, we can of course easily extend that)

* extract_disk_from_import_file: this actually extracts the file from
  the archive. Currently only ova is supported, so the extraction with
  'tar' is hardcoded, but again we can easily extend/modify that should
  we need to.

  we currently extract into the import storage in a directory named:
  `.tmp_<pid>_<targetvmid>` which should not clash with concurrent
  operations (though we do extract it multiple times then)

  alternatively we could implement either a 'tmpstorage' parameter,
  or use e.g. '/var/tmp/' or similar, but re-using the current storage
  seemed ok.

* cleanup_extracted_image: intended to cleanup the extracted images from
  above, including the surrounding temporary directory

we have to modify the `parse_ovf` a bit to handle the missing disk
images, and we parse the size out of the ovf part (since this is
informal only, it should be no problem if we cannot parse it sometimes)

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 src/PVE/API2/Storage/Status.pm |  1 +
 src/PVE/Storage.pm             | 59 ++++++++++++++++++++++++++++++++++
 src/PVE/Storage/DirPlugin.pm   | 13 +++++++-
 src/PVE/Storage/OVF.pm         | 53 ++++++++++++++++++++++++++----
 src/PVE/Storage/Plugin.pm      |  5 +++
 5 files changed, 123 insertions(+), 8 deletions(-)

diff --git a/src/PVE/API2/Storage/Status.pm b/src/PVE/API2/Storage/Status.pm
index f7e324f..77ed57c 100644
--- a/src/PVE/API2/Storage/Status.pm
+++ b/src/PVE/API2/Storage/Status.pm
@@ -749,6 +749,7 @@ __PACKAGE__->register_method({
 				'efi-state-lost',
 				'guest-is-running',
 				'nvme-unsupported',
+				'ova-needs-extracting',
 				'ovmf-with-lsi-unsupported',
 				'serial-port-socket-only',
 			    ],
diff --git a/src/PVE/Storage.pm b/src/PVE/Storage.pm
index f8ea93d..bc073ef 100755
--- a/src/PVE/Storage.pm
+++ b/src/PVE/Storage.pm
@@ -2189,4 +2189,63 @@ sub get_import_metadata {
     return $plugin->get_import_metadata($scfg, $volname, $storeid);
 }
 
+sub copy_needs_extraction {
+    my ($volid) = @_;
+    my ($storeid, $volname) = parse_volume_id($volid);
+    my $cfg = config();
+    my $scfg = storage_config($cfg, $storeid);
+    my $plugin = PVE::Storage::Plugin->lookup($scfg->{type});
+
+    my ($vtype, $name, $vmid, $basename, $basevmid, $isBase, $file_format) =
+	$plugin->parse_volname($volname);
+
+    return $vtype eq 'import' && defined($file_format);
+}
+
+sub extract_disk_from_import_file {
+    my ($volid, $vmid) = @_;
+
+    my ($storeid, $volname) = parse_volume_id($volid);
+    my $cfg = config();
+    my $scfg = storage_config($cfg, $storeid);
+    my $plugin = PVE::Storage::Plugin->lookup($scfg->{type});
+
+    my ($vtype, $name, undef, undef, undef, undef, $file_format) =
+	$plugin->parse_volname($volname);
+
+    die "only files with content type 'import' can be extracted\n"
+	if $vtype ne 'import' || !defined($file_format);
+
+    # extract the inner file from the name
+    if ($volid =~ m!${name}/([^/]+)$!) {
+	$name = $1;
+    }
+
+    my ($source_file) = $plugin->path($scfg, $volname, $storeid);
+
+    my $destdir = $plugin->get_subdir($scfg, 'import');
+    my $pid = $$;
+    $destdir .= "/.tmp_${pid}_${vmid}";
+    mkdir $destdir;
+
+    ($source_file) = $source_file =~ m|^(/.*)|; # untaint
+
+    run_command(['tar', '-x', '-C', $destdir, '-f', $source_file, $name]);
+
+    return "$destdir/$name";
+}
+
+sub cleanup_extracted_image {
+    my ($source) = @_;
+
+    if ($source =~ m|^(/.+/\.tmp_[0-9]+_[0-9]+)/[^/]+$|) {
+	my $tmpdir = $1;
+
+	unlink $source or $! == ENOENT or die "removing image $source failed: $!\n";
+	rmdir $tmpdir or $! == ENOENT or die "removing tmpdir $tmpdir failed: $!\n";
+    } else {
+	die "invalid extraced image path '$source'\n";
+    }
+}
+
 1;
diff --git a/src/PVE/Storage/DirPlugin.pm b/src/PVE/Storage/DirPlugin.pm
index 4dc7708..50ceab7 100644
--- a/src/PVE/Storage/DirPlugin.pm
+++ b/src/PVE/Storage/DirPlugin.pm
@@ -260,14 +260,25 @@ sub get_import_metadata {
     # NOTE: all types must be added to the return schema of the import-metadata API endpoint
     my $warnings = [];
 
+    my $isOva = 0;
+    if ($path =~ m!\.ova!) {
+	$isOva = 1;
+	push @$warnings, { type => 'ova-needs-extracting' };
+    }
     my $res = PVE::Storage::OVF::parse_ovf($path, $isOva);
     my $disks = {};
     for my $disk ($res->{disks}->@*) {
 	my $id = $disk->{disk_address};
 	my $size = $disk->{virtual_size};
 	my $path = $disk->{relative_path};
+	my $volid;
+	if ($isOva) {
+	    $volid = "$storeid:$volname/$path";
+	} else {
+	    $volid = "$storeid:import/$path",
+	}
 	$disks->{$id} = {
-	    volid => "$storeid:import/$path",
+	    volid => $volid,
 	    defined($size) ? (size => $size) : (),
 	};
     }
diff --git a/src/PVE/Storage/OVF.pm b/src/PVE/Storage/OVF.pm
index 4a322b9..fb850a8 100644
--- a/src/PVE/Storage/OVF.pm
+++ b/src/PVE/Storage/OVF.pm
@@ -85,11 +85,37 @@ sub id_to_pve {
     }
 }
 
+# technically defined in DSP0004 (https://www.dmtf.org/dsp/DSP0004) as an ABNF
+# but realistically this always takes the form of 'bytes * base^exponent'
+sub try_parse_capacity_unit {
+    my ($unit_text) = @_;
+
+    if ($unit_text =~ m/^\s*byte\s*\*\s*([0-9]+)\s*\^\s*([0-9]+)\s*$/) {
+	my $base = $1;
+	my $exp = $2;
+	return $base ** $exp;
+    }
+
+    return undef;
+}
+
 # returns two references, $qm which holds qm.conf style key/values, and \@disks
 sub parse_ovf {
-    my ($ovf, $debug) = @_;
+    my ($ovf, $isOva, $debug) = @_;
+
+    # we have to ignore missing disk images for ova
+    my $dom;
+    if ($isOva) {
+	my $raw = "";
+	PVE::Tools::run_command(['tar', '-xO', '--wildcards', '--occurrence=1', '-f', $ovf, '*.ovf'], outfunc => sub {
+	    my $line = shift;
+	    $raw .= $line;
+	});
+	$dom = XML::LibXML->load_xml(string => $raw, no_blanks => 1);
+    } else {
+	$dom = XML::LibXML->load_xml(location => $ovf, no_blanks => 1);
+    }
 
-    my $dom = XML::LibXML->load_xml(location => $ovf, no_blanks => 1);
 
     # register the xml namespaces in a xpath context object
     # 'ovf' is the default namespace so it will prepended to each xml element
@@ -177,7 +203,17 @@ sub parse_ovf {
 	# @ needs to be escaped to prevent Perl double quote interpolation
 	my $xpath_find_fileref = sprintf("/ovf:Envelope/ovf:DiskSection/\
 ovf:Disk[\@ovf:diskId='%s']/\@ovf:fileRef", $disk_id);
+	my $xpath_find_capacity = sprintf("/ovf:Envelope/ovf:DiskSection/\
+ovf:Disk[\@ovf:diskId='%s']/\@ovf:capacity", $disk_id);
+	my $xpath_find_capacity_unit = sprintf("/ovf:Envelope/ovf:DiskSection/\
+ovf:Disk[\@ovf:diskId='%s']/\@ovf:capacityAllocationUnits", $disk_id);
 	my $fileref = $xpc->findvalue($xpath_find_fileref);
+	my $capacity = $xpc->findvalue($xpath_find_capacity);
+	my $capacity_unit = $xpc->findvalue($xpath_find_capacity_unit);
+	my $virtual_size;
+	if (my $factor = try_parse_capacity_unit($capacity_unit)) {
+	    $virtual_size = $capacity * $factor;
+	}
 
 	my $valid_url_chars = qr@${valid_uripath_chars}|/@;
 	if (!$fileref || $fileref !~ m/^${valid_url_chars}+$/) {
@@ -217,23 +253,26 @@ ovf:Item[rasd:InstanceID='%s']/rasd:ResourceType", $controller_id);
 	    die "error parsing $filepath, are you using a symlink ?\n";
 	}
 
-	if (!-e $backing_file_path) {
+	if (!-e $backing_file_path && !$isOva) {
 	    die "error parsing $filepath, file seems not to exist at $backing_file_path\n";
 	}
 
 	($backing_file_path) = $backing_file_path =~ m|^(/.*)|; # untaint
 	($filepath) = $filepath =~ m|^(.*)|; # untaint
 
-	my $virtual_size = PVE::Storage::file_size_info($backing_file_path);
-	die "error parsing $backing_file_path, cannot determine file size\n"
-	    if !$virtual_size;
+	if (!$isOva) {
+	    my $size = PVE::Storage::file_size_info($backing_file_path);
+	    die "error parsing $backing_file_path, cannot determine file size\n"
+		if !$size;
 
+	    $virtual_size = $size;
+	}
 	$pve_disk = {
 	    disk_address => $pve_disk_address,
 	    backing_file => $backing_file_path,
-	    virtual_size => $virtual_size
 	    relative_path => $filepath,
 	};
+	$pve_disk->{virtual_size} = $virtual_size if defined($virtual_size);
 	push @disks, $pve_disk;
 
     }
diff --git a/src/PVE/Storage/Plugin.pm b/src/PVE/Storage/Plugin.pm
index deaf8b2..ea069ab 100644
--- a/src/PVE/Storage/Plugin.pm
+++ b/src/PVE/Storage/Plugin.pm
@@ -654,6 +654,11 @@ sub parse_volname {
 	return ('backup', $fn);
     } elsif ($volname =~ m!^snippets/([^/]+)$!) {
 	return ('snippets', $1);
+    } elsif ($volname =~ m!^import/([^/]+\.ova)\/([^/]+)$!) {
+	my $archive = $1;
+	my $file = $2;
+	my (undef, $format, undef) = parse_name_dir($file);
+	return ('import', $archive, 0, undef, undef, undef, $format);
     } elsif ($volname =~ m!^import/([^/]+$PVE::Storage::IMPORT_EXT_RE_1)$!) {
 	return ('import', $1);
     } elsif ($volname =~ m!^import/([^/]+\.(raw|vmdk|qcow2))$!) {
-- 
2.39.2