containerd/pkg/apparmor/apparmor_linux.go
Eng Zer Jun 50da673592
refactor: move from io/ioutil to io and os package
The io/ioutil package has been deprecated as of Go 1.16, see
https://golang.org/doc/go1.16#ioutil. This commit replaces the existing
io/ioutil functions with their new definitions in io and os packages.

Signed-off-by: Eng Zer Jun <engzerjun@gmail.com>
2021-09-21 09:50:38 +08:00

44 lines
1.4 KiB
Go

/*
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 apparmor
import (
"os"
"sync"
)
var (
appArmorSupported bool
checkAppArmor sync.Once
)
// hostSupports 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 hostSupports() bool {
checkAppArmor.Do(func() {
// see https://github.com/opencontainers/runc/blob/0d49470392206f40eaab3b2190a57fe7bb3df458/libcontainer/apparmor/apparmor_linux.go
if _, err := os.Stat("/sys/kernel/security/apparmor"); err == nil && os.Getenv("container") == "" {
buf, err := os.ReadFile("/sys/module/apparmor/parameters/enabled")
appArmorSupported = err == nil && len(buf) > 1 && buf[0] == 'Y'
}
})
return appArmorSupported
}