Is allowing port 80 on Little Snitch safe?

Solution 1:

No.

If, for all processes.

Pretty much yes.

If, only for web browsing.

As @StuWilson has pointed out, port 80 is for http traffic and port 443 is for https traffic. (http with TLS/SSL encryption).

It's not necessary to allow all traffic of all processes on port 80. But - for the sake of comfortable browsing - I strongly recommend enabling those ports for all traffic of webbrowsers like Safari or Chrome.

For comparison, this is my setup of Chrome in HandsOff!:

• Basic communication

  • Allow all outgoing network connections on port 443 (https)
  • Allow all outgoing network connections on port 80 (http)
  • Allow all domain resolving

• Sync

  • Allow all outgoing network connections to talk.google.com on port 5222

• Other (e.g. media)

  • Allow all outgoing network connections to atracktive.collegehumor.com on port 9090 (websm)
  • ...

Setting up a firewall can be quite a hassle. Generally - when I've expected a certain connection to build up, and know what it's for, I allow it. But you should only interfere network connections when you know what you're doing.

Many system processses regulary build up (local) network connections that are certainly valid. If you don't know how to guard a firewall, you become the first security risk for your own computer. Make sure to educate yourself on network protocols when building your own firewall.

Solution 2:

Port 80 is the standard port for all HTTP traffic, so disallowing port 80 will give you a popup for all web browsers and web sites.

Little Snitch is about telling you what is on your machine trying to communicate with other things.

Rules are generally about Program A, Port B, Destination C

So you could have a rule that says, "Safari", Port 80, "All Destinations" which would allow Safari to browse the web, but that would stop Google Chrome doing the same.

Note in the real world, there are other ports such as those for HTTPS (443) that would also be open.