forked from tianon/gosu
/
main.go
54 lines (44 loc) · 1.31 KB
/
main.go
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package main // import "github.com/LTD-Beget/gosu"
import (
"log"
"os"
"os/exec"
"runtime"
"syscall"
)
const MIN_UID = 999
const MIN_GID = 999
func init() {
// use seccomp if not root
if syscall.Geteuid() > 0 {
initSeccomp()
}
// make sure we only have one process and that it runs on the main thread (so that ideally, when we Exec, we keep our user switches and stuff)
runtime.GOMAXPROCS(1)
runtime.LockOSThread()
}
func main() {
log.SetFlags(0) // no timestamps on our logs
if len(os.Args) <= 2 {
log.Printf("Usage: %s user-spec command [args]", os.Args[0])
log.Printf(" ie: %s tianon bash", os.Args[0])
log.Printf(" %s nobody:root bash -c 'whoami && id'", os.Args[0])
log.Printf(" %s 1000:1 id", os.Args[0])
log.Println()
log.Printf("%s version: %s (%s on %s/%s; %s)", os.Args[0], Version, runtime.Version(), runtime.GOOS, runtime.GOARCH, runtime.Compiler)
log.Println()
os.Exit(1)
}
// clear HOME so that SetupUser will set it
os.Setenv("HOME", "")
if err := SetupUser(os.Args[1]); err != nil {
log.Fatalf("error: failed switching to %q: %v", os.Args[1], err)
}
name, err := exec.LookPath(os.Args[2])
if err != nil {
log.Fatalf("error: %v", err)
}
if err = syscall.Exec(name, os.Args[2:], os.Environ()); err != nil {
log.Fatalf("error: exec failed: %v", err)
}
}