I'm running a node.js server, that will serve requests on port 80 amongst others. Clearly this requires the application running as root (on Linux).
Looking at this post (http://syskall.com/dont-run-node-dot-js-as-root) as an example it's clear that there are simple ways to allow node to be run as a non-root user, but I'm wondering if anyone has views on the advantages/disadvantages of the different methods suggested:
code: use setuid() to drop down from root to non-priviledged user after listening on port 80 is established.
using a proxy server of some sort to redirect requests to a port >1024 (and so not need node to run as root)
using IP tables to forward to another port (ditto node would not run as root)
Thanks
Option 1 requires you launch the node server as root. Not ideal.
Option 2 adds overhead to every handled request and adds another failure point to your stack.
Option 3 Is the simplest and most efficient method.
To implement Option 3, add the following to your system init scripts. (/etc/rc.d/rc.local on RedHat based systems like AWS).
iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT --to-port 3000
That will redirect requests from port 80 to port 3000.
(I haven't got enough reputation to add a comment the the one of Matt Browne, so I write this as an answer. Feel free to edit.)
There is a simpler method to load iptables rules automatically after a reboot than the one described in the link of Matt Browne: One can install iptables-persistent from the repositories using apt-get:
apt-get install iptables-persistent
Rules still need to be saved manually like this:
IPv4:
iptables-save > /etc/iptables/rules.v4
IPv6:
iptables-save > /etc/iptables/rules.v6
(Source: http://www.thomas-krenn.com/de/wiki/Iptables_Firewall_Regeln_dauerhaft_speichern (german))