X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=TODO;h=2479bbb19bd9c72d9005845d09784d8dda47fb60;hp=0aeceb7a4a82ab73edaa00f0a29eb6e65115a3ab;hb=dc8e4b057ecd3984d7c27c8e;hpb=fe491524cefd1ede281debbc128dab4ce26d7ab6 diff --git a/TODO b/TODO index 0aeceb7..2479bbb 100644 --- a/TODO +++ b/TODO @@ -1,111 +1,50 @@ -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 - ----------------------------------------------------------------------- - -Implement febootstrap command. - ----------------------------------------------------------------------- +Haskell bindings +---------------- Complete the Haskell bindings (see discussion on haskell-cafe). ----------------------------------------------------------------------- - -Complete the bindings tests - must test the return values and -error cases. - ----------------------------------------------------------------------- - -For virt-inspector: - - - Make a libvirt XML config - - - Test over available OSes - - - Add 'reged' / NT registry support. - ----------------------------------------------------------------------- - -Use virtio_blk by default. It's faster and more natural. -Unfortunately it seems like this will rename all devices - see next -item. - -Note: virtio_blk *IS* supported by all our minimum platforms, -ie. CentOS 5.3, Fedora 11, Debian. - ----------------------------------------------------------------------- - -"Device independent" naming for devices. - -With a Fedora-based appliance, using libata driver, devices have -"SCSI" names like /dev/sda. - -With an EPEL-based appliance, using old ide driver, devices have names -like /dev/hda. - -If we use virtio_blk, devices will have names like /dev/vda. +PHP bindings +------------ -What a mess. +Add bindtests to PHP bindings. -So the idea would be to add a device independent naming scheme, such -as the one used by grub: +Complete bind tests +------------------- - "(hdX)" X = 0 means 'a', X = 1 means 'b' and so on. - "(hdX,Y)" Device X, partition Y (in grub, this counts from 0 which is - deeply confusing). +Complete the bind tests - must test the return values and error cases. -There would have to be a very simple rule. If guestfsd was expecting -a /dev block device or partition name, then the alternate form can be -used, and we would just look it up using the normal output of -guestfs_list_devices. +virt-inspector - make libvirt XML +--------------------------------- -Maybe best is to use /dev/sda as the "standard" naming. That -shouldn't cause conflicts in the appliance because we tightly control -what drivers are available. +It should be possible to generate libvirt XML from virt-inspector +data, at least partially. This would be just another output type so: -Note there's a lot of hackery that currently exists in tests.c which -could be *removed* if we made this change. + virt-inspector --libvirt guest.img -Open: Should the substitution be done in the library layer or in the -daemon? - ----------------------------------------------------------------------- - -Qemu options -- After discussion with the KVM developers, they have -recommended some flags which will improve the safety and reliability -of KVM. Need to test that these also work under qemu (or at least, do -no harm): - --no-hpet HPET support is broken and should be disabled. - --rtc-td-hack Keeps the rtc clock source track time correctly. - --drive file=...,if=[ide|virtio],cache=off - cache=off is necessary to improve reliability in the - event of a system crash when writing. - ----------------------------------------------------------------------- +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. @@ -143,3 +82,344 @@ 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 + + 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? + +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). + +[I tried to implement this in the new C virt-rescue, but it doesn't +work. qemu is implementing its own ptys, and they are broken. Need +to fix qemu.] + +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. + +[Not sure this is such a good idea. See also live CD inspection idea below.] + +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? + +See also contribs/visualize-alignment/ + +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/ + +Fix 'file' +---------- + +https://www.redhat.com/archives/libguestfs/2010-June/msg00053.html +https://www.redhat.com/archives/libguestfs/2010-June/msg00079.html + +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 / + +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: + + - 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). + +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. + +guestfish parsing +----------------- + +At the moment guestfish uses an ad hoc parser which has many +shortcomings. We should change to using a lex/yacc-based scanner and +parser (there are better parsers out there, but yacc is sufficient and +very widely available). + +The scanner must deal with the case of parsing a whole command string, +eg. for a command that the user types in: + + > add-drive-opts "/tmp/foo" readonly:true + +and also with parsing single words from the command line: + + guestfish add-drive-opts /tmp/foo readonly:true + +Note the quotes are for scanning and don't indicate types. + +We should also allow variables and expressions as part of this new +parsing code, eg: + + set roots inspect-os + set product inspect-get-product-name %{roots[0]} + +% is better than $ because of shell escaping and confusion with shell +variables. + +Can we combine this with ability to set and read environment +variables? Currently guestfish uses many environment variables like +$EDITOR without any corresponding ability to set them. + + set EDITOR /usr/bin/emacs + echo $EDITOR # or %{EDITOR} + edit /etc/resolv.conf + +live CD inspection for Windows 7 +-------------------------------- + +Windows 7 install CDs are quite different and pretty impenetrable. +There are no obvious files to parse. + +More ntfs tools +--------------- + +ntfsprogs actually has a lot more useful tools than we currently +use. Interesting ones are: + +ntfslabel: display or change filesystem label (we should unify all + set*label APIs into a single set_vfs_label which can deal with any + filesystem) + +ntfsclone: clone, image, restore, rescue NTFS + +ntfsinfo: print various information about NTFS volume and files + +ntfs streams: extract alternate streams from NTFS files + +Undelete files +-------------- + +Two useful tools: + + - ext2undelete + - ntfsundelete + +More mkfs_opts options +---------------------- + +Useful options to offer: + - Set label. + - Set UUID. + +Use /proc/self/mountinfo +------------------------ + +This file contains lots of interesting information about +what is mounted and where. eg: + + 16 21 0:3 / /proc rw,relatime - proc /proc rw + 17 21 0:16 / /sys rw,relatime - sysfs /sys rw,seclabel + 18 23 0:5 / /dev rw,relatime - devtmpfs udev rw,seclabel,size=1906740k,nr_inodes=476685,mode=755 + 26 21 253:3 / /home rw,relatime - ext4 /dev/mapper/vg-lv_home rw,seclabel,barrier=1,data=ordered + +This could be used instead of current hairy code to parse the output +of the 'mount' command. We could add new APIs to return kernel mount +options, type of filesystem at a mountpoint etc.