Changing routed traffic's MAC address on the fly

0

I'm using Internet Sharing on a MacBook Pro, and my hotel's WiFi is inspecting MAC addresses, so sharing doesn't work. For example, when I log into the hotel's WiFi using a web browser, it assigns my laptop an IP and only lets traffic from that IP through if the traffic is coming from my laptop's MAC address.

Is there any way that I can take each packet (as it is routed by my MacBook) and modify it so that it matches my laptop's MAC address?

Dutch

Posted 2015-11-18T01:13:31.937

Reputation: 9

Are you 100% sure you're using OSX Internet Sharing and not bridging? – David Schwartz – 2015-11-18T01:25:16.363

100% sure I'm using Internet Sharing. – Dutch – 2015-11-18T22:05:52.643

Answers

1

Internet Sharing in OS X already does NAT, so it already makes all of your traffic look like it's coming from your MacBook Pro's IP and MAC address (the address of the "Share…From:" interface).

So something else is going on here. Maybe the hotel has NAT detection?

Spiff

Posted 2015-11-18T01:13:31.937

Reputation: 84 656

Hmm. I talked to the ISP and they said that my hotel has disallowed "passthroughs." – Dutch – 2015-11-18T22:06:18.333

@Dutch, Unfortunately, that's response from the ISP is phrased in layman's terms, and it's really hard to know what that means at a technical level. – Spiff – 2015-11-18T23:36:19.400

Yeah. I think I was talking to a layman. He couldn't (or wouldn't) be more specific. – Dutch – 2015-11-19T00:45:38.920

If we assume it is NAT detection, is there any way around that? – Dutch – 2015-11-19T00:45:54.077

@Dutch First check the output of "ifconfig" to verify that nothing has added the wireless interface to the bridge. Then let's see a packet trace of the Wi-Fi interface traffic of both the MacBook Pro accessing the Internet, and a NAT client failing to access the Internet. If you've been messing with static configs on the Ethernet, I'd undo those and reboot the MacBook Pro in case your routing tables got messed up. – Spiff – 2015-11-19T01:43:31.630

Asked: 2015-11-18T01:13:31.937

Viewed: 49 times

Active: 2015-11-18T01:25:26.203