resign

Safely drop elevated (root) permissions for system security. This allows you to do things like bind to privileged ports (<1024), use the ping command, etc., and then release the permissions so that an attacker will not be able to compromise the entire server.

Quick Start

Simply require the resign module and call it like any other function. The exported function (resign(user, group) in this case) takes 2 (optional) parameters: user and group names or numeric IDs to assume the role of. If omitted, the function will attempt to grab a sudo user and group ID from the environment.

Sample script (sample.js):

var resign = require("resign"),
    report = function () {
        console.log("UID:  %d, GID:  %d", process.getuid(),  process.getgid());
        console.log("EUID: %d, EGID: %d", process.geteuid(), process.getegid());
    };

if (process.getuid() == 0) {
    console.log("I am root.");
    report();
}

resign();

if (process.getuid() != 0) {
    console.log("My root privileges have been dropped.");
    report();
}

Output:

$ sudo node sample.js
I am root.
UID:  0, GID:  0
EUID: 0, EGID: 0
My root privileges have been dropped.
UID:  1000, GID:  1000
EUID: 1000, EGID: 1000