We want to be able to use container without the PID namespace. We basically
want containers that can manage the host os, which I call Super Privileged
Containers. We eventually would like to get to the point where the only
namespace we use is the MNT namespace to bring the Apps userspace with it.
By eliminating the PID namespace we can get better communication between the
host and the clients and potentially tools like strace and gdb become easier
to use. We also see tools like libvirtd running within a container telling
systemd to place a VM in a particular cgroup, we need to have communications of the PID.
I don't see us needing to share PID namespaces between containers, since this
is really what docker exec does.
So currently I see us just needing docker run --pid=host
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
This commit contains changes for docker:
* user.GetGroupFile to user.GetGroupPath docker/libcontainer#301
* Add systemd support for OOM docker/libcontainer#307
* Support for custom namespaces docker/libcontainer#279, docker/libcontainer#312
* Fixes#9699docker/libcontainer#308
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Some workloads rely on IPC for communications with other processes. We
would like to split workloads between two container but still allow them
to communicate though shared IPC.
This patch mimics the --net code to allow --ipc=host to not split off
the IPC Namespace. ipc=container:CONTAINERID to share ipc between containers
If you share IPC between containers, then you need to make sure SELinux labels
match.
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Since the containers can handle the out of memory kernel kills gracefully, docker
will only provide out of memory information as an additional metadata as part of
container status.
Docker-DCO-1.1-Signed-off-by: Vishnu Kannan <vishnuk@google.com> (github: vishh)
We removed the syncpipe package and replaced it with specific calls to
create a new *os.File from a specified fd passed to the process. This
reduced code and an extra object to manage the container's init
lifecycle.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Right now, MAC addresses are randomly generated by the kernel when
creating the veth interfaces.
This causes different issues related to ARP, such as #4581, #5737 and #8269.
This change adds support for consistent MAC addresses, guaranteeing that
an IP address will always end up with the same MAC address, no matter
what.
Since IP addresses are already guaranteed to be unique by the
IPAllocator, MAC addresses will inherit this property as well for free.
Consistent mac addresses is also a requirement for stable networking (#8297)
since re-using the same IP address on a different MAC address triggers the ARP
issue.
Finally, this change makes the MAC address accessible through docker
inspect, which fixes#4033.
Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>
This also removes dead code in the native driver for a past feature that
was never fully implemented.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This changes the way the exec drivers work by not specifing a -driver
flag on reexec. For each of the exec drivers they register their own
functions that will be matched aginst the argv 0 on exec and called if
they match.
This also allows any functionality to be added to docker so that the
binary can be reexec'd and any type of function can be called. I moved
the flag parsing on docker exec to the specific initializers so that the
implementations do not bleed into one another. This also allows for
more flexability within reexec initializers to specify their own flags
and options.
Signed-off-by: Michael Crosby <michael@docker.com>
lxc is special in that we cannot create the master outside of the
container without opening the slave because we have nothing to provide to the
cmd. We have to open both then do the crazy setup on command right now instead of
passing the console path to lxc and telling it to open up that console. we save a couple of
openfiles in the native driver because we can do this.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@docker.com> (github: crosbymichael)
This patch adds pause/unpause to the command line, api, and drivers
for use on containers. This is implemented using the cgroups/freeze
utility in libcontainer and lxc freeze/unfreeze.
Co-Authored-By: Eric Windisch <ewindisch@docker.com>
Co-Authored-By: Chris Alfonso <calfonso@redhat.com>
Docker-DCO-1.1-Signed-off-by: Ian Main <imain@redhat.com> (github: imain)
This also makes sure that devices are pointers to avoid copies
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
We now have one place that keeps track of (most) devices that are allowed and created within the container. That place is pkg/libcontainer/devices/devices.go
This fixes several inconsistencies between which devices were created in the lxc backend and the native backend. It also fixes inconsistencies between wich devices were created and which were allowed. For example, /dev/full was being created but it was not allowed within the cgroup. It also declares the file modes and permissions of the default devices, rather than copying them from the host. This is in line with docker's philosphy of not being host dependent.
Docker-DCO-1.1-Signed-off-by: Timothy Hobbs <timothyhobbs@seznam.cz> (github: https://github.com/timthelion)
Add specific types for Required and Optional DeviceNodes
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
We need SETFCAP to be able to mark files as having caps, which is
heavily used by fedora.
See https://github.com/dotcloud/docker/issues/5928
We also need SETPCAP, for instance systemd needs this to set caps
on its childen.
Both of these are safe in the sense that they can never ever
result in a process with a capability not in the bounding set of the
container.
We also add NET_BIND_SERVICE caps, to be able to bind to ports lower
than 1024.
Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
those that were specified in the config. This commit also explicitly
adds a set of capabilities that we were silently not dropping and were
assumed by the tests.
Docker-DCO-1.1-Signed-off-by: Victor Marmol <vmarmol@google.com> (github: vmarmol)
This updates systemd.Apply to match the fs backend by:
* Always join blockio controller (for stats)
* Support CpusetCpus
* Support MemorySwap
Also, it removes the generic UnitProperties in favour of a single
option to set the slice.
Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
This also cleans up some of the left over restriction paths code from
before.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
It has been pointed out that some files in /proc and /sys can be used
to break out of containers. However, if those filesystems are mounted
read-only, most of the known exploits are mitigated, since they rely
on writing some file in those filesystems.
This does not replace security modules (like SELinux or AppArmor), it
is just another layer of security. Likewise, it doesn't mean that the
other mitigations (shadowing parts of /proc or /sys with bind mounts)
are useless. Those measures are still useful. As such, the shadowing
of /proc/kcore is still enabled with both LXC and native drivers.
Special care has to be taken with /proc/1/attr, which still needs to
be mounted read-write in order to enable the AppArmor profile. It is
bind-mounted from a private read-write mount of procfs.
All that enforcement is done in dockerinit. The code doing the real
work is in libcontainer. The init function for the LXC driver calls
the function from libcontainer to avoid code duplication.
Docker-DCO-1.1-Signed-off-by: Jérôme Petazzoni <jerome@docker.com> (github: jpetazzo)
Kernel capabilities for privileged syslog operations are currently splitted into
CAP_SYS_ADMIN and CAP_SYSLOG since the following commit:
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=ce6ada35bdf710d16582cc4869c26722547e6f11
This patch drops CAP_SYSLOG to prevent containers from messing with
host's syslog (e.g. `dmesg -c` clears up host's printk ring buffer).
Closes#5491
Docker-DCO-1.1-Signed-off-by: Eiichi Tsukata <devel@etsukata.com> (github: Etsukata)
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
This duplicates some of the Exec code but I think it it worth it because
the native driver is more straight forward and does not have the
complexity have handling the type issues for now.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
This temp. expands the Exec method's signature but adds a more robust
way to know when the container's process is actually released and begins
to run. The network interfaces are not guaranteed to be up yet but this
provides a more accurate view with a single callback at this time.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
This has every container using the docker daemon's pid for the processes
label so it does not work correctly.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
This will allow for these to be set independently. Keep the current Docker behavior where Memory and MemoryReservation are set to the value of Memory.
Docker-DCO-1.1-Signed-off-by: Victor Marmol <vmarmol@google.com> (github: vmarmol)