The api allows for creating, listing, and restoring of container
snapshots. Snapshots are created as snapshot clones of the
original container - i.e. btrfs and lvm will be done as snapshot,
a directory-backed container will have overlayfs snapshots. A
restore is a copy-clone, using the same backing store as the
original container had.
Changelog:
. remove lxcapi_snap_open, which wasn't defined anyway.
. rename get_comment to get_commentpath
. if no newname is specified at restore, use c->name (as we meant to)
rather than segving.
. when choosing a snapshot index, use the correct path to check for.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Search for Lua if no --enable-lua/--disable-lua specified but continue
without if not found.
If --enable-lua is specified and Lua is not found then return error.
If --disable-lua is specified, then don't search for Lua.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Otherwise containers may be able to remount -o ro their rootfs
at shutdown.
Reported-by: Harald Dunkel <harri@afaics.de>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
When there is no --enable-lua or --with-lua-pc, Lua should not be
enabled.
This fixes a bug introduced with 12e93188 (configure/makefile:
Allow specify Lua pkg-config file with --with-lua-pc) that caused
configure script to fail if lua headers was missing.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Instead of popen and run external executable dirname we implement a
dirname in C in the core module.
We also remove the unused basename function.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Enable support for both Lua 5.1 and 5.2 by letting user specify the Lua
pkg-config package name. By default it will use 'lua' and try figure
out which version it is.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
The lxc configuration file currently supports 'lxc.cap.drop', a list of
capabilities to be dropped (using the bounding set) from the container.
The problem with this is that over time new capabilities are added. So
an older container configuration file may, over time, become insecure.
Walter has in the past suggested replacing lxc.cap.drop with
lxc.cap.preserve, which would have the inverse sense - any capabilities
in that set would be kept, any others would be dropped.
Realistically both have the same problem - the sendmail capabilities
bug proved that running code with unexpectedly dropped privilege can be
dangerous. This patch gives the admin a choice: You can use either
lxc.cap.keep or lxc.cap.drop, not both.
Both continue to be ignored if a user namespace is in use.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
We already add harware address for a single veth interface. Do the same
with a single macvlan interface.
Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
We wish to ensure that, henceforth, newer lxc tools are always compatible
with older lxc monitors. Add a comment to commands.c to explain the
rule we wish to enforce to this end.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Signalfd does not guarantee that we'll get an event for every signal.
So if 3 tasks exit at the same time, we may get only one sigchld
event. Therefore, in signal_handler(), always check whether init has
exited. Do with with WNOWAIT so that we can still wait4 to cleanup
the init after lxc_poll() exists (rather than complicating the code).
Note - there is still a race in the kernel which can cause the
container init to become a defunct child of the host init (!). This
doesn't solve that, but is a potential (if very unlikely) race which
apw pointed out while we were trying to create a reproducer for the
kernel bug.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Stéphane Graber <stgraber@ubuntu.com>
Normal lxc-start usage tends to be "lxc-start -n name [-P lxcpath]".
This causes $lxcpath/$name/config to be the configuration for the
container. However, lxc-start is more flexible than that. You can
specify a custom configuration file, in which case $lxcpath/$name/config
is not used. You can also (in addition or in place of either of these)
specify configuration entries one-by-one using "-s lxc.utsname=xxx".
To support this using the API, if we are not using
$lxcpath/$name/config then we put ourselves into a custom lxcpath
called (configurable using LXCPATH) /var/lib/lxc_anon. To stop a
container so created, then, you would use
lxc-stop -P /var/lib/lxc_anon -n name
TODO: we should walk over the list of &defines by hand and set them
using c->set_config_item. I haven't done that in this patch.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
prior to my enabling of the clone hook, the setting of the hostname
was being done by writing to /etc/hostname. Instead of relying on that
we're now writing 'local-hostname' into the metadata for the instance.
cloud-init then reads this and sets the hostname properly.
We are also writing /etc/hostname with the new hostname explicitly. This is
useful/necessary because on network bringup of eth0, dhclient will submit its
hosname. The updating done by cloud-init occurs to late, and thus
the dhcp request goes out with the un-configured hostname and dns doens't
work correctly.
Signed-off-by: Scott Moser <smoser@ubuntu.com>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
These are the last of the simpler conversions. Start, execute,
kill, info and attach remain to be done.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Dwight Engen <dwight.engen@oracle.com>
(Will push in a bit barring any objections)
lvm, btrfs, and zfs snapshots each do an ok job of handling deletions
for us - a btrfs snapshot does fine after the original is removed,
while zfs and lvm will both refuse to allow the original to be deleted
while the snapshot exists.
Overlayfs doesn't do this for us. So, for overlayfs snapshots, track
the dependencies.
When c2 is created as an overlayfs snapshot of dir-backed c1, then
1. c2's lxc_rdepends file will contain
c1_lxcpath
c1_lxcname
2. c1's lxc_snapshots will contain "1"
c1 cannot be deleted so long as lxc_snapshots exists and contains
a non-zero number.
The contents of lxc_snapshots and lxc_rdepends are protected by
container_disk_lock() and at lxc_clone by the new container not yet
being accessible.
(Originally I was going to keep them in the container config, but the
problem with using $lxcpath/$name/config is that api users could end up
calling c->save_config() with a cached old value of snapshots/rdepends.)
Changelog:
aug 21: check for fprintf and fclose failures
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Acked-by: Dwight Engen <dwight.engen@oracle.com>
