Similar to the (now removed) `apparmor` build tag, this build-time toggle existed for users who needed to build without the `libseccomp` library. That's no longer necessary, and given the importance of seccomp to the overall default security profile of Docker containers, it makes sense that any binary built for Linux should support (and use by default) seccomp if the underlying host does.
Signed-off-by: Tianon Gravi <admwiggin@gmail.com>
The `daemon.RawSysInfo()` function can be a heavy operation, as it collects
information about all cgroups on the host, networking, AppArmor, Seccomp, etc.
While looking at our code, I noticed that various parts in the code call this
function, potentially even _multiple times_ per container, for example, it is
called from:
- `verifyPlatformContainerSettings()`
- `oci.WithCgroups()` if the daemon has `cpu-rt-period` or `cpu-rt-runtime` configured
- in `ContainerDecoder.DecodeConfig()`, which is called on boith `container create` and `container commit`
Given that this information is not expected to change during the daemon's
lifecycle, and various information coming from this (such as seccomp and
apparmor status) was already cached, we may as well load it once, and cache
the results in the daemon instance.
This patch updates `daemon.RawSysInfo()` to use a `sync.Once()` so that
it's only executed once for the daemon's lifecycle.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This allows containers to use the embedded default profile if a different
default is set (e.g. "unconfined") in the daemon configuration. Without this
option, users would have to copy the default profile to a file in order to
use the default.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Commit b237189e6c implemented an option to
set the default seccomp profile in the daemon configuration. When that PR
was reviewed, it was discussed to have the option accept the path to a custom
profile JSON file; https://github.com/moby/moby/pull/26276#issuecomment-253546966
However, in the implementation, the special "unconfined" value was not taken into
account. The "unconfined" value is meant to disable seccomp (more factually:
run with an empty profile).
While it's likely possible to achieve this by creating a file with an an empty
(`{}`) profile, and passing the path to that file, it's inconsistent with the
`--security-opt seccomp=unconfined` option on `docker run` and `docker create`,
which is both confusing, and makes it harder to use (especially on Docker Desktop,
where there's no direct access to the VM's filesystem).
This patch adds the missing check for the special "unconfined" value.
Co-authored-by: Tianon Gravi <admwiggin@gmail.com>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Format the source according to latest goimports.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
This fix tries to address the issue raised in #24374 where
`docker info` outputs seccomp support in Ubuntu 14.04 but
the seccomp wass not actually supported.
The issue is that in the current docker implementation, seccomp
support is only checked against the kernel by inspect CONFIG_SECCOMP
and CONFIG_SECCOMP_FILTER. However, seccomp might not be enabled
when building docker (through golang build flag).
This fix adds a supportSeccomp boolean variable. The supportSeccomp
is only set to true when seccomp is enabled when building docker.
This fix fixes#24374.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Currently the default seccomp profile is fixed. This changes it
so that it varies depending on the Linux capabilities selected with
the --cap-add and --cap-drop options. Without this, if a user adds
privileges, eg to allow ptrace with --cap-add sys_ptrace then still
cannot actually use ptrace as it is still blocked by seccomp, so
they will probably disable seccomp or use --privileged. With this
change the syscalls that are needed for the capability are also
allowed by the seccomp profile based on the selected capabilities.
While this patch makes it easier to do things with for example
cap_sys_admin enabled, as it will now allow creating new namespaces
and use of mount, it still allows less than --cap-add cap_sys_admin
--security-opt seccomp:unconfined would have previously. It is not
recommended that users run containers with cap_sys_admin as this does
give full access to the host machine.
It also cleans up some architecture specific system calls to be
only selected when needed.
Signed-off-by: Justin Cormack <justin.cormack@docker.com>
