Files
my-rook-config/pkg/daemon/ceph/osd/nsenter.go
T
Krzysztof Nazarewski 352df4e62f osd: add NixOS specific PATHs
This commits makes Rook usable on NixOS.

NixOS system holds "installed" binaries in `/run/current-system/sw/{bin,sbin}`.
The only binaries residing outside those paths are `/usr/bin/env` and `/bin/sh`.

I got a suggestion on Slack to simply add those NixOS specific paths

Signed-off-by: Krzysztof Nazarewski <3494992+nazarewk@users.noreply.github.com>
2022-04-01 16:37:23 +02:00

97 lines
2.8 KiB
Go

/*
Copyright 2020 The Rook Authors. All rights reserved.
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 osd
import (
"fmt"
"os"
"path/filepath"
"github.com/pkg/errors"
"github.com/rook/rook/pkg/clusterd"
)
const (
// mountNsPath is the default mount namespace of the host
mountNsPath = "/rootfs/proc/1/ns/mnt"
// nsenterCmd is the nsenter command
nsenterCmd = "nsenter"
rootFSPath = "/rootfs"
)
var (
binPathsToCheck = []string{"/usr/sbin", "/sbin/", "/run/current-system/sw/bin", "/run/current-system/sw/sbin"}
)
// NSEnter is an nsenter object
type NSEnter struct {
context *clusterd.Context
binary string
binaryArgs []string
}
// NewNsenter returns an instance of the NSEnter object
func NewNsenter(context *clusterd.Context, binary string, binaryArgs []string) *NSEnter {
return &NSEnter{
context: context,
binary: binary,
binaryArgs: binaryArgs,
}
}
func (ne *NSEnter) buildNsEnterCLI(binPath string) []string {
baseArgs := []string{fmt.Sprintf("--mount=%s", mountNsPath), "--", binPath}
baseArgs = append(baseArgs, ne.binaryArgs...)
return baseArgs
}
func (ne *NSEnter) callNsEnter(binPath string) error {
args := ne.buildNsEnterCLI(binPath)
op, err := ne.context.Executor.ExecuteCommandWithCombinedOutput(nsenterCmd, args...)
if err != nil {
return errors.Wrapf(err, "failed to execute nsenter. output: %s", op)
}
logger.Info("successfully called nsenter")
return nil
}
func (ne *NSEnter) checkIfBinaryExistsOnHost() error {
for _, path := range binPathsToCheck {
binPath := filepath.Join(path, ne.binary)
// Check with nsenter first
err := ne.callNsEnter(binPath)
if err != nil {
logger.Debugf("failed to call nsenter. %v", err)
// If nsenter failed, let's try with the rootfs directly but only lookup the binary and do not execute it
// This avoids mismatch libraries between the container and the host while executing
rootFSBinPath := filepath.Join(rootFSPath, binPath)
_, err := os.Stat(rootFSBinPath)
if err != nil {
logger.Debugf("failed to lookup binary path %q on the host rootfs. %v", rootFSBinPath, err)
continue
}
binPath = rootFSBinPath
}
logger.Infof("binary %q found on the host, proceeding with osd preparation", binPath)
return nil
}
return errors.Errorf("binary %q does not exist on the host", ne.binary)
}