coder/cli/clistat/container.go

71 lines
2.0 KiB
Go

package clistat
import (
"bufio"
"bytes"
"os"
"github.com/spf13/afero"
"golang.org/x/xerrors"
)
const (
procMounts = "/proc/mounts"
procOneCgroup = "/proc/1/cgroup"
kubernetesDefaultServiceAccountToken = "/var/run/secrets/kubernetes.io/serviceaccount/token" //nolint:gosec
)
// IsContainerized returns whether the host is containerized.
// This is adapted from https://github.com/elastic/go-sysinfo/tree/main/providers/linux/container.go#L31
// with modifications to support Sysbox containers.
// On non-Linux platforms, it always returns false.
func IsContainerized(fs afero.Fs) (ok bool, err error) {
cgData, err := afero.ReadFile(fs, procOneCgroup)
if err != nil {
if os.IsNotExist(err) {
return false, nil
}
return false, xerrors.Errorf("read file %s: %w", procOneCgroup, err)
}
scn := bufio.NewScanner(bytes.NewReader(cgData))
for scn.Scan() {
line := scn.Bytes()
if bytes.Contains(line, []byte("docker")) ||
bytes.Contains(line, []byte(".slice")) ||
bytes.Contains(line, []byte("lxc")) ||
bytes.Contains(line, []byte("kubepods")) {
return true, nil
}
}
// Sometimes the above method of sniffing /proc/1/cgroup isn't reliable.
// If a Kubernetes service account token is present, that's
// also a good indication that we are in a container.
_, err = afero.ReadFile(fs, kubernetesDefaultServiceAccountToken)
if err == nil {
return true, nil
}
// Last-ditch effort to detect Sysbox containers.
// Check if we have anything mounted as type sysboxfs in /proc/mounts
mountsData, err := afero.ReadFile(fs, procMounts)
if err != nil {
if os.IsNotExist(err) {
return false, nil
}
return false, xerrors.Errorf("read file %s: %w", procMounts, err)
}
scn = bufio.NewScanner(bytes.NewReader(mountsData))
for scn.Scan() {
line := scn.Bytes()
if bytes.Contains(line, []byte("sysboxfs")) {
return true, nil
}
}
// If we get here, we are _probably_ not running in a container.
return false, nil
}