v1.13.0

ADDED:
* Convenience functions to determine if a process is running in an
  elevated/dropped privileges context

funcs_linux.go

@@ -0,0 +1,50 @@
+package sysutils
+
+import (
+	`fmt`
+	`os`
+
+	`golang.org/x/sys/unix`
+	`r00t2.io/sysutils/envs`
+)
+
+// GetIDState returns current ID/elevation information. An IDState should *not* be explicitly created/defined.
+func GetIDState() (ids IDState) {
+
+	var err error
+
+	ids.RUID, ids.EUID, ids.SUID = unix.Getresuid()
+	ids.uidsChecked = true
+	ids.RGID, ids.EGID, ids.SGID = unix.Getresgid()
+	ids.gidsChecked = true
+
+	ids.SudoEnvCmd = envs.HasEnv("SUDO_COMMAND")
+	ids.SudoEnvHome = envs.HasEnv("SUDO_HOME")
+	ids.SudoEnvGroup = envs.HasEnv("SUDO_GID")
+	ids.SudoEnvUser = envs.HasEnv("SUDO_UID") || envs.HasEnv("SUDO_USER")
+	if ids.SudoEnvCmd || ids.SudoEnvHome || ids.SudoEnvGroup || ids.SudoEnvUser {
+		ids.SudoEnvVars = true
+	}
+	ids.sudoChecked = true
+
+	// PID 1 will *always* be root, so that can return a false positive for sudo.
+	if os.Getppid() != 1 {
+		ids.stat = new(unix.Stat_t)
+		if err = unix.Stat(
+			fmt.Sprintf("/proc/%d/stat", os.Getppid()),
+			ids.stat,
+		); err != nil {
+			err = nil
+		} else {
+			ids.PPIDUidMatch = ids.RUID == int(ids.stat.Uid)
+			ids.ppidUidChecked = true
+			ids.PPIDGidMatch = ids.RGID == int(ids.stat.Gid)
+			ids.ppidGidChecked = true
+		}
+	} else {
+		ids.ppidUidChecked = true
+		ids.ppidGidChecked = true
+	}
+
+	return
+}