LAN port scan forbidder

Forbid non-LAN web to access LAN

Forbid untrusted web to scan localhost or LAN. ## Source Code Repo https://github.com/garywill/LAN-port-scan-forbidder ## What Webs can try to fetch `127.0.0.1:xxxx` or `192.168.Y.Z:xxxx` to scan your open ports in LAN. Although browsers have cross-domain protections, webs can't read response contents, **but** can still see the connection succeeds or fails. There're already reports that some websites using that as tracking fingerprint. > A web for testing: http://samy.pl/webscan/ ## So Forbid any website behaviors trying to connect to your LAN or localhost, if user is visiting the website via their domains or public IP addresses. (Read the source code `background.js` to see the logic) > Using JS library [whitequark/ipaddr.js](https://github.com/whitequark/ipaddr.js) (MIT License) v2.0.0 to judge IP range. ### Notification User can enable notification. When untrusted web tries to access private network and get blocked, will show up notification. ### Fallback operation If user find a web broken, user can temporary set this addon disabled via toolbar button for: - this one tab - this one tab and new tabs opened by this tab - this one window (Firefox only) - globally (above can be set as keyboard shortcuts) there's showy toolbar button badge indicating disabling status. ## Cases when web LAN scan is properly used Not all LAN-port-scan are evil. - Some manufacturers provide web for user's browser to scan LAN for their product that need updating. - Some softwares use `127.0.0.1` communication to interact between native program and web. ## Disclaimer This open souce addon comes with no warranty. Use on you own risk!