Icanhazip: A simple IP address tool survived a deluge of users (2021)

Post by arjvik » Tue, Aug 01, 2023, 2:41 AM UTC

dfc wrote: post #87

arjvik wrote: post #85

Earlier quoted context omitted.

There's a whole list of such resolvers: Akamai: dig +short whoami.akamai.net @ns1-1.akamaitech.net Google: dig +short o-o.myaddr.l.google.com txt @ns1.google.com Cloudflare: dig +short whoami.cloudflare ch txt @1.1.1.1 OpenDNS: dig -4 +short myip.opendns.com @resolver1.opendns.com Note that if you leave off the `@service.authoritative.nameserver` portion of all of the above, you get the IP address of the recursive re…

The opendns server does not return anything if I send the query to anything other than opendns.

Post by tchbnl » Tue, Aug 01, 2023, 3:02 AM UTC

Snawoot wrote: post #28

Why not use protocols which are specifically designed to report mapped IP address like STUN? It's faster as UDP exchange is shorter than 3-way TCP handshake (or even TCP+TLS handshake). Here is an implementation which uses parallel STUN queries to report address reliably as fast as possible: https://github.com/Snawoot/myip

Post by e28eta » Tue, Aug 01, 2023, 3:21 AM UTC

matthberg wrote: post #84

gaudat wrote: post #81

Earlier quoted context omitted.

My favorite: https://cloudflare.com/cdn-cgi/trace

/cdn-cgi/trace isn't available on just cloudflare.com, it's on every site they proxy too (there might be a setting somewhere to disable it yet it's on by default). I've yet to figure out what happens if your site also serves something there, yet it was surprising to see on a barebones site I had routed through them. I learned this from: https://news.ycombinator.com/item?id=36383258

Post by 1vuio0pswjnm7 » Tue, Aug 01, 2023, 4:01 AM UTC

gaudat wrote: post #81

zie wrote: post #30

For ridiculously easy things like this, I think it's smarter for you to just host it yourself. This way you are not forcing other people to carry your burden. nginx config example: location /ip { add_header Content-Type "application/json"; return 200 '{"host":"$server_name","ip":"$remote_addr","port":"$remote_port","server_ip":"$server_addr","server_port":"$server_port "}\n'; } Which will return something like this i…

My favorite: https://cloudflare.com/cdn-cgi/trace

   sni=plaintext

Post by quickthrower2 » Tue, Aug 01, 2023, 4:22 AM UTC

francislavoie wrote: post #74

zie wrote: post #30

For ridiculously easy things like this, I think it's smarter for you to just host it yourself. This way you are not forcing other people to carry your burden. nginx config example: location /ip { add_header Content-Type "application/json"; return 200 '{"host":"$server_name","ip":"$remote_addr","port":"$remote_port","server_ip":"$server_addr","server_port":"$server_port "}\n'; } Which will return something like this i…

Alternatively, with Caddy (with automated TLS, single static binary): example.com { handle /ip { header Content-Type application/json respond `{"host":"{host}","ip":"{remote_host}","port":"{remote_port}"}` } } Though the usefulness of the host (client specified it), remote port (it's random), and server ip/port (it's static and not useful for the client) are questionable.