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|
package hooks
import (
deos "github.com/hlandau/goutils/os"
"os"
"os/exec"
)
func runningAsRoot() bool {
return os.Getuid() == 0
}
func fileIsScript(fn string) bool {
f, err := os.Open(fn)
if err != nil {
return false
}
defer f.Close()
var b [2]byte
n, _ := f.Read(b[:])
if n < 2 {
return false
}
return string(b[:]) == "#!"
}
// Vulnerable to race conditions, but this is just a check. sudo enforces all
// security properties.
func shouldSudoFile(fn string, fi os.FileInfo) bool {
if runningAsRoot() {
return false
}
_, err := exec.LookPath("sudo")
if err != nil {
return false
}
// Only setuid files if the setuid bit is set.
if (fi.Mode() & os.ModeSetuid) == 0 {
return false
}
// Don't sudo anything which appears to be setuid'd for a non-root user.
// This doesn't really buy us anything security-wise, but it's not what
// we're expecting.
uid, err := deos.GetFileUID(fi)
if err != nil || uid != 0 {
return false
}
// Make sure the file is a script, otherwise we can just execute it directly.
return fileIsScript(fn)
}
|
