X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=TODO;h=6ab6dc614c12c6d2380e3e4b2ee842ffe0faa870;hp=323dc0b4f7e8ccf96183737cc0740a8b6ef198d0;hb=f48cd1f262312ad278a293a20ab442dcfc076a69;hpb=af7e3fc047447ff77ade4640194f9ec519068951 diff --git a/TODO b/TODO index 323dc0b..6ab6dc6 100644 --- a/TODO +++ b/TODO @@ -1,51 +1,406 @@ -Ideas for the Python bindings: -https://www.redhat.com/archives/fedora-virt/2009-April/msg00114.html +TODO list for libguestfs +====================================================================== ----------------------------------------------------------------------- +This list contains random ideas and musings on features we could add +to libguestfs in future. -We badly need to actually implement the FTP server mentioned in the -documentation. + - RWMJ -Or: Implement a FUSE-based filesystem. See the FUSE mountlo -project which does something similar, albeit only to single -filesystems: +FUSE API +-------- -http://sourceforge.net/project/showfiles.php?group_id=121684&package_id=150116 +The API needs more test coverage, particularly lesser-used system +calls. ----------------------------------------------------------------------- +The big unresolved issue is UID/GID mapping between guest filesystem +IDs and the host. It's not easy to automate this because you need +extra details about the guest itself in order to get to its +UID->username map (eg. /etc/passwd from the guest). -BufferIn and BufferOut should turn into and simple -strings in other languages that can handle 8 bit clean strings. -Limit on transfers would still be 2MB for these types. - - then implement write-file properly - - and implement read-file +febootstrap / debootstrap inside appliance +------------------------------------------ ----------------------------------------------------------------------- +This was originally proposed as a way to install new operating systems +in the appliance. However no one has come up with a workable +solution. -Implement febootstrap command. - ----------------------------------------------------------------------- +Haskell bindings +---------------- Complete the Haskell bindings (see discussion on haskell-cafe). ----------------------------------------------------------------------- +PHP bindings +------------ + +Add bindtests to PHP bindings. + +Complete bind tests +------------------- + +Complete the bind tests - must test the return values and error cases. + +virt-inspector - make libvirt XML +--------------------------------- + +It should be possible to generate libvirt XML from virt-inspector +data, at least partially. This would be just another output type so: + + virt-inspector --libvirt guest.img + +Note that recent versions of libvirt/virt-install allow guests to be +imported, so this is not so useful any more. + +"Standalone/local mode" +----------------------- + +Instead of running guestfsd (the daemon) inside qemu, there should be +an option to just run guestfsd directly. + +The architecture in this mode would look like: + + +------------------+ + | main program | + |------------------| + | libguestfs | + +--------^---------+ + | | reply + cmd | | + +----v-------------+ + | guestfsd | + +------------------+ + +Notes: + +(1) This only makes sense if we are running as root. + +(2) There is no console / kernel messages in this configuration, but +we might consider capturing stderr from the daemon. + +(3) guestfs_config and guestfs_add_drive become no-ops. + +Obviously in this configuration, commands are run directly on the +local machine's disks. You could just run the commands themselves +directly, but libguestfs provides a convenient API and language +bindings. Also deals with tricky stuff like parsing the output of the +LVM commands. Also we get to leverage other code such as +virt-inspector. + +This is mainly useful from live CDs, ie. virt-p2v. + +Should we bother having the daemon at all and just link the guestfsd +code directly into libguestfs? + +Ideas for extra commands +------------------------ + + General glibc / core programs: + chgrp + more mk*temp calls + + ext2 properties: + chattr + lsattr + badblocks + blkid + debugfs + dumpe2fs + e2image + e2undo + filefrag + findfs + logsave + mklost+found + ext2undelete + + SELinux: + chcat + restorecon + ch??? + + Oddball: + pivot_root + fts(3) / ftw(3) + +Other initrd-* commands +----------------------- + +Such as: + +initrd-extract +initrd-replace + +Simple editing of configuration files +------------------------------------- + +Some easy non-Augeas methods to edit configuration files. +I'm thinking: + + replace /etc/file key value + +which would look in /etc/file for any instances of + + key=... + key ... + key:... + +and replace them with + + key=value + key value + key:value + +That would solve about 50% of reconfiguration needs, and for the +rest you'd use Augeas, 'download'+'upload' or 'edit'. + +RWMJ: I had a go at implementing this, but it's quite error-prone to +do this sort of editing inside the C-based daemon code. It's far +better to do it with Augeas, or else to use an external language like +Perl. + +Quick Perl scripts +------------------ + +Currently we can't do Perl "one-liners". ie. The current syntax for +any short Perl one-liner would be: + + perl -MSys::Guestfs -e '$g = Sys::Guestfs->new(); $g->add_drive ("foo"); $g->launch; $g->mount ("/dev/sda1", "/"); ....' + +You can see we're well beyond a single line just getting to the point +of adding drives and mounting. + +First suggestion: + + $h = create ($filename, \"/dev/sda1\" => \"/\"); + + $h = create ([$file1, $file2], \"/dev/sda1\" => \"/\"); + +To mount read-only, add C 1> like this: + + $h = create ($filename, \"/dev/sda1\" => \"/\", ro => 1); + +which is equivalent to the following sequence of calls: + + $h = Sys::Guestfs->new (); + $h->add_drive_ro ($filename); + $h->launch (); + $h->mount_ro (\"/dev/sda1\", \"/\"); + +Command-line form would be: + + perl -MSys::Guestfs=:all -e '$_=create("guest.img", "/dev/sda1" => "/"); $_->cat ("/etc/fstab");' + +That's not brief enough for one-liners, so we could have an extra +autogenerated module which creates a Sys::Guestfs handle singleton +(the handle is an implicit global variable as in guestfish), eg: + + perl -MSys::Guestfs::One -e 'inspect("guest.img"); cat ("/etc/fstab");' + +How would editing files work? + +ntfsclone +--------- + +Useful imaging tool: +http://man.linux-ntfs.org/ntfsclone.8.html + +virt-rescue pty +--------------- + +See: +http://search.cpan.org/~rgiersig/IO-Tty-1.08/Pty.pm +http://www.perlmonks.org/index.pl?node_id=582185 + +Note that pty requires cooperation inside the C code too (there are +two sides to a pty, and one has to be handled after the fork). + +Windows-based daemon/appliance +------------------------------ + +See discussion on list: +https://www.redhat.com/archives/libguestfs/2009-November/msg00165.html + +qemu locking +------------ + +Add -drive file=...,lock=exclusive and -drive file=...,lock=shared + +Change libguestfs and libvirt to do the right thing, so that multiple +instances of qemu cannot stomp on each other. + +virt-disk-explore +----------------- + +For multi-level disk images such as live CDs: +http://rwmj.wordpress.com/2009/07/15/unpack-the-russian-doll-of-a-f11-live-cd/ + +It's possible with libguestfs to recursively look for anything that +might be a filesystem, mount-{,loop} it and look in those, revealing +anything in a disk image. + +However this won't work easily for VM disk images in the disk image. +One would have to download those to the host and launch another +libguestfs instance. + +List, mount filesystems by UUID and label +----------------------------------------- + +[See related: +http://www.redhat.com/archives/libguestfs/2009-August/msg00031.html] + +List filesystems by UUID or label. + +Mount filesystems by UUID or label. (I'm not really sure if we can do +this at the moment but we ought to be able to do it, and perhaps make +it easier by having a direct command). + +Map filesystems to disk blocks +------------------------------ + +Map files/filesystems/(any other object) to the actual disk +blocks they occupy. + +And vice versa. + +Is it even possible? + +Integration with host intrusion systems +--------------------------------------- + +Perfect way to monitor VMs from outside the VM. Look for file +hashes, log events, login/logout etc. + +http://www.ossec.net/ +http://la-samhna.de/samhain/ +http://sourceforge.net/projects/aide/ +http://osiris.shmoo.com/ +http://sourceforge.net/projects/tripwire/ + +-N option should be generated +----------------------------- + +'-N' option should generate documentation in guestfish(1) manpage. + +Fix 'file' +---------- + +https://www.redhat.com/archives/libguestfs/2010-June/msg00053.html +https://www.redhat.com/archives/libguestfs/2010-June/msg00079.html + +Regression test on virt-inspector +--------------------------------- + +Occasionally we break virt-inspector through some change. We should +add a regression test for it. However this is hard because we'd need +to avoid having to carry huge images. + +Update: I managed to fit a real-but-minimal Fedora 13 image into 6.2 MB. +See: http://rwmj.wordpress.com/2010/09/07/tip-pack-files-into-a-new-disk-image/#content + +Freeze/thaw filesystems +----------------------- + +Access to these ioctls: +http://git.kernel.org/linus/fcccf502540e3d7 + +Tips for new users in guestfish +------------------------------- + +$ guestfish +Tip: You need to 'add disk.img' or 'alloc disk.img nn' to make a new image. +Type 'notips' to disable tips permanently. +> add mydisk +Tip: You need to type 'run' before you can see into the disk image. +> run +Tip: Use 'list-filesystems' to see what filesystems are available. +> list-filesystems +/dev/vda1 +Tip: Use 'mount fs /' to mount a filesystem. +> mount /dev/vda1 / +Tip: Use 'll /' to view the filesystem or ... +> ll / + +New guestfish commands +---------------------- + +'list-filesystems' => list mountable filesystems + +We could implement this as a new API call, replacing a number of areas +of the current code where this is done already (in virt-inspector and +elsewhere). What we normally do to find out if a partition contains a +mountable filesystem is to just blindly mount it, and see if that +succeeds. However the kernel won't let us do this if the filesystem +is already mounted somewhere, so a naive implementation of this in the +daemon won't work. We would have to check if the partition was +already mounted. + +Could we make guestfish interactive if commands are used without params? +------------------------------------------------------------------------ + +> sparse +[[Prints man page]] +Image name? disk.img +Size of image? 10M + +Common problems +--------------- + +How can we solve these common user problems? + +[space for common problems here] + +Better support for encrypted devices +------------------------------------ + +Currently LUKS support only works if the device contains volume +groups. If it contains, eg., partitions, you cannot access them. +We would like to add: + + - An easier way to use this from guestfish. + - Direct access to the /dev/mapper device (eg. if it contains + anything apart from VGs). + +Display image as PS +------------------- + +Display the structure of an image file as a PS. + +Greater use of blkid / libblkid +------------------------------- + +guestfs_zero should use wipefs. See wipefs(8). + +There are various useful functions in libblkid for listing partitions, +devices etc which we are essentially duplicating in the daemon. It +would make more sense to just use libblkid for this. + +There are some places where we call out to the 'blkid' program. This +might be replaced by direct use of the library (if this is easier). + +Remove repo from appliance name +------------------------------- + +There's no need to have the appliance name contain the repository name +(ie initramfs.x86_64.img instead of initramfs.fedora-13.x86_64.img). + +Visualization +------------- + +Eric Sandeen pointed out the blktrace tool which is a better way of +capturing traces than using patched qemu (see +contrib/visualize-alignment). We would still use the same +visualization tools in conjunction with blktrace traces. + +Virt-df UUID +------------ -Practically, resizing the partitions when a block device is resized -isn't possible. So for example it's not possible to resize a Fedora -block device. If you try to use sfdisk-N to change the boundaries of -the existing partition to fill up the new space, you get an error that -the partition is in use. +Virt-df and any other tools with --csv output should be able to print +UUID of domain. This allows you to track the real domain across +renames etc. -The reason, I now think, is because LVM is using the partition as a -PV, and this locks it as far as the kernel is concerned. +Add-domain command +------------------ -Removing the PV [which is what we do in the test suite] isn't -desirable if the PV contains data you care about. Rebooting the qemu -subprocess after the partition table change works, but isn't very -cool. I believe what we need to do is to temporarily reconfigure LVM -(using /etc/lvm/lvm.conf) to ignore the PV, vgscan (which will then -ignore the PV), make the changes to the partition table, then set the -LVM configuration back and do a final vgscan. +guestfs_add_domain (g, "libvirt-dom"); -Need to test the above, and find a nice way to present it through -the API. +However this would need to not depend on libvirt, eg. loading it +on demand.