On Thu, Feb 23, 2012 at 01:44:35AM +0200, Zeeshan Ali (Khattak) wrote: > On Thu, Feb 23, 2012 at 1:25 AM, Daniel P. Berrange <berrange@xxxxxxxxxx> wrote: > > On Thu, Feb 23, 2012 at 12:44:15AM +0200, Zeeshan Ali (Khattak) wrote: > >> On Tue, Feb 21, 2012 at 7:46 PM, Daniel P. Berrange <berrange@xxxxxxxxxx> wrote: > >> > From: "Daniel P. Berrange" <berrange@xxxxxxxxxx> > >> > >> I really should have paid more attention before ACKing some of the > >> patches. :) Here is the problem introduced by this one: > >> > >> > --- > >> > data/oses/ubuntu.xml | 731 ++++++++++++++++++++++++++++++++++++++++++++++++-- > >> > 1 files changed, 711 insertions(+), 20 deletions(-) > >> > > >> > diff --git a/data/oses/ubuntu.xml b/data/oses/ubuntu.xml > >> > index 78239f6..fb331a3 100644 > >> > --- a/data/oses/ubuntu.xml > >> > +++ b/data/oses/ubuntu.xml > >> > @@ -6,6 +6,35 @@ > >> > <version>4.10</version> > >> > <vendor>Canonical</vendor> > >> > <family>Linux</family> > >> > + > >> > + <media arch="i386"> > >> > + <url>http://old-releases.ubuntu.com/releases/warty/warty-release-install-i386.iso</url> > >> > + <iso> > >> > + <volume-id>Ubuntu 4.10 i386</volume-id> > >> > + <system-id>LINUX</system-id> > >> > + </iso> > >> > + <kernel>casper/vmlinuz</kernel> > >> > + <initrd>casper/initrd.img</initrd> > >> > + </media> > >> .. > >> > + > >> > + <media arch="i386" live="true" installer="false"> > >> > + <url>http://old-releases.ubuntu.com/releases/warty/warty-release-live-i386.iso</url> > >> > + <iso> > >> > + <volume-id>Ubuntu 4.10 i386</volume-id> > >> > + <system-id>LINUX</system-id> > >> > + </iso> > >> > + <kernel>casper/vmlinuz</kernel> > >> > + <initrd>casper/initrd.img</initrd> > >> > + </media> > >> > >> With volume and system ID being identical for both medias, only the > >> first media will be matched against both types of medias. Same goes > >> for other medias you added in this patch. Wonder what could be a > >> solution here though. Perhaps detection code should check if there is > >> multiple matches and it there are, match basename of known URL against > >> that of media's patch? > > > > Yep, the name is about the only difference between them - all the ISO > > metadata is identical. The other thing I considered is to add an MD5 > > checksum of the ISO file, which would trivially distinguish them, > > but I fear that would make it too unique. > > That might be a very good idea actually (Christophe was meaning to do > that any ways?) but calculation of md5 takes a very long time: > > $ time md5sum ~/ISOs/Fedora-16-x86_64-DVD.iso > bb38ea1fe4b2fc69e7a6e15cf1c69c91 /home/zeenix/ISOs/Fedora-16-x86_64-DVD.iso > > real 0m23.348s > user 0m9.276s > sys 0m1.654s > > so I'll recommend to restrict it to first N bytes, where we could > think/discuss the value of N but 1MiB should be good enough and takes > very little time: > > $ time dd if=~/ISOs/Fedora-16-x86_64-DVD.iso bs=1M count=1 2> /dev/null |md5sum > e25ea147176f24239d38a46f501bd25e - > > real 0m0.011s > user 0m0.004s > sys 0m0.008s > > Actually if we start using md5sum for detection, we can pretty much > remove all other detection logic/extraction. Actually I really wouldn't want to remove the other logic - I think that a checksum could well be too strict, eliminating matches that should otherwise be allowed. I'd prefer just to use it to resolve ambiguity when we have multiple matches. A 1 MB checksum would very likely be sufficient here. I think we should also have a full checksum in the database to, so that if an app downloads a remote ISO based on an osinfo URL, it can verify the download is correct Some remote download sites actually provide checksum files, so it might be desirable to have either <checksum url="http:/...."/> <checksum value="XXXXXXXXXXXXXX"/> And once we do this kind of thing, we might also consider having a GPG signature URL too, for sites that publish those. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|
