badguardhome/internal/aghos/os_linux.go

82 lines
1.6 KiB
Go

// +build linux
package aghos
import (
"bytes"
"io/ioutil"
"os"
"path/filepath"
"strings"
"syscall"
"github.com/AdguardTeam/golibs/log"
"golang.org/x/sys/unix"
)
func canBindPrivilegedPorts() (can bool, err error) {
cnbs, err := unix.PrctlRetInt(unix.PR_CAP_AMBIENT, unix.PR_CAP_AMBIENT_IS_SET, unix.CAP_NET_BIND_SERVICE, 0, 0)
// Don't check the error because it's always nil on Linux.
adm, _ := haveAdminRights()
return cnbs == 1 || adm, err
}
func setRlimit(val uint) {
var rlim syscall.Rlimit
rlim.Max = uint64(val)
rlim.Cur = uint64(val)
err := syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rlim)
if err != nil {
log.Error("Setrlimit() failed: %v", err)
}
}
func haveAdminRights() (bool, error) {
// The error is nil because the platform-independent function signature
// requires returning an error.
return os.Getuid() == 0, nil
}
func sendProcessSignal(pid int, sig syscall.Signal) error {
return syscall.Kill(pid, sig)
}
func isOpenWrt() (ok bool) {
const etcDir = "/etc"
// TODO(e.burkov): Take care of dealing with fs package after updating
// Go version to 1.16.
fileInfos, err := ioutil.ReadDir(etcDir)
if err != nil {
return false
}
// fNameSubstr is a part of a name of the desired file.
const fNameSubstr = "release"
osNameData := []byte("OpenWrt")
for _, fileInfo := range fileInfos {
if fileInfo.IsDir() {
continue
}
fn := fileInfo.Name()
if !strings.Contains(fn, fNameSubstr) {
continue
}
var body []byte
body, err = ioutil.ReadFile(filepath.Join(etcDir, fn))
if err != nil {
continue
}
if bytes.Contains(body, osNameData) {
return true
}
}
return false
}