/
uexec.go
62 lines (58 loc) · 1.08 KB
/
uexec.go
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package main
import (
"flag"
"fmt"
"os"
"os/exec"
"os/user"
"strconv"
"syscall"
)
var userName = flag.String("user", "", "user name")
func main() {
flag.Usage = func() {
fmt.Println("usage: uexec [-user=user] command")
fmt.Println("")
fmt.Println("Works like sudo -u, but does not messs with your environment (including LD_LIBRARY_PATH).")
fmt.Println("")
flag.PrintDefaults()
}
flag.Parse()
args := flag.Args()
if len(args) < 1 {
flag.Usage()
os.Exit(1)
}
path, err := exec.LookPath(args[0])
if err != nil {
panic(err)
}
args[0] = path
env := os.Environ()
if *userName != "" {
if err := changeUser(*userName); err != nil {
panic(err)
}
}
if err := syscall.Exec(path, args, env); err != nil {
panic(err)
}
}
func changeUser(name string) error {
user, err := user.Lookup(name)
if err != nil {
return err
}
uid, err := strconv.Atoi(user.Uid)
if err != nil {
return err
}
gid, err := strconv.Atoi(user.Gid)
if err = syscall.Setgroups([]int{gid}); err != nil {
return err
}
if err = syscall.Setuid(uid); err != nil {
return err
}
return nil
}