containerd/pkg/cri/server/apparmor.go
Sebastiaan van Stijn eba94a15c8
pkg/cri/server: remove dependency on libcontainer/apparmor, libcontainer/utils
recent versions of libcontainer/apparmor simplified the AppArmor
check to only check if the host supports AppArmor, but no longer
checks if apparmor_parser is installed, or if we're running
docker-in-docker;

bfb4ea1b1b

> The `apparmor_parser` binary is not really required for a system to run
> AppArmor from a runc perspective. How to apply the profile is more in
> the responsibility of higher level runtimes like Podman and Docker,
> which may do the binary check on their own.

This patch copies the logic from libcontainer/apparmor, and
restores the additional checks.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2020-11-12 15:42:25 +01:00

49 lines
1.5 KiB
Go

// +build apparmor,linux
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package server
import (
"io/ioutil"
"os"
"sync"
)
var (
appArmorSupported bool
checkAppArmor sync.Once
)
// hostSupportsAppArmor returns true if apparmor is enabled for the host, if
// apparmor_parser is enabled, and if we are not running docker-in-docker.
//
// It is a modified version of libcontainer/apparmor.IsEnabled(), which does not
// check for apparmor_parser to be present, or if we're running docker-in-docker.
func hostSupportsAppArmor() bool {
checkAppArmor.Do(func() {
// see https://github.com/docker/docker/commit/de191e86321f7d3136ff42ff75826b8107399497
if _, err := os.Stat("/sys/kernel/security/apparmor"); err == nil && os.Getenv("container") == "" {
if _, err = os.Stat("/sbin/apparmor_parser"); err == nil {
buf, err := ioutil.ReadFile("/sys/module/apparmor/parameters/enabled")
appArmorSupported = err == nil && len(buf) > 1 && buf[0] == 'Y'
}
}
})
return appArmorSupported
}