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Seems to rely on https://api.ipify.org/ https://api.ipify.org/ to determine public IP. Is there any Cloudflare service one can use to determine the IP instead?

Seems to rely on https://api.ipify.org/ https://api.ipify.org/ to determine public IP. Is there any Cloudflare service one can use to determine the IP instead? That way there’s not an extra company in addition to Cloudflare itself that you need to continue existing.

teamspirit 2y ago
https://www.cloudflare.com/cdn-cgi/trace https://www.cloudflare.com/cdn-cgi/trace will return your ip.
- mxuribe 2y ago
  The (above) shared url leveraging the cloudflare.com domain name seems to show ip v6 address, while I've noticed that the following defaults to showing ip v4 address: https://1.1.1.1/cdn-cgi/trace https://1.1.1.1/cdn-cgi/trace Pick your poison as you wish - either is great! :-)
  - codetrotter 2y ago
    I’d pick the one that supports IPv6 and then make two separate requests to it. One request over IPv4 and one over IPv6. curl -4 https://www.cloudflare.com/cdn-cgi/trace curl -6 https://www.cloudflare.com/cdn-cgi/trace Also the reason that the 1.1.1.1 one shows only IPv4 address is because 1.1.1.1 is itself an IPv4 address. So any connection to it will have to be using IPv4.
    - tcfhgj 2y ago
      could you not retrieve your ipv6 directly from the system?
      - codetrotter 2y ago
        Yes, but getting it in a response from an external server means I don’t have to be specific about which interface to get the IPv6 address of and so on.
        tcfhgj 2y ago
        the same specific interface used to contact the external server
        wizzwizz4 2y ago
        i.e., an arbitrarily-selected interface capable of reaching Cloudflare.
        codetrotter 2y ago
        Which is neatly abstracted away so you don’t have to think about it unless you want to. And therefore reaching out to an external server and having it say where the request came from is the path of least resistance for a script that can work across different hosts with minimal machine specific configuration. Listen, if you want to check the IPv6 address from the interface list go ahead I’m not trying to stop you. But because I anyway need to reach a third party to know my own IPv4 address then yeah when that third party can also tell me IPv6 address I’m gonna do it that way.
        graton 2y ago
        That requires running it on the router/device which gets the public IP address. By using the service you can update your DNS IP address on a system that is behind the router.
        tcfhgj 2y ago
        What do you mean? Every device gets a public ipv6 (usually).
        graton 2y ago
        I have a router connected to the internet, it gets the public IP address. The router is connected to the internal network in my home and has the IP address of 192.168.1.1. Behind the router is my computer which has a non-public IP address, for example 192.168.1.2. My computer is the one I want to run the program to update the DNS entry. My computer does not know what the public IP address is by looking at its interfaces.
- macote 2y ago
  This is how I use it in my bash script: current_ip=$(curl -s -X GET https://1.1.1.1/cdn-cgi/trace | grep -Po "(?<=ip=)(.*)")
  - networked 2y ago
    I find awk more clear for this kind of job. You can replace grep -Po "(?<=ip=)(.*)" with awk -F= '$1 == "ip" { print $2 }'
    - macote 2y ago
      Thanks for that, I agree.
- immibis 2y ago
  Works on every cloudflare-MITMed domain btw.
victorbjorklund 2y ago
You could do it with a cloudflare worker that just returns the ip address of the request
- victorbjorklund 2y ago
  Nevermind. The other answer is better
gothink 2y ago
I feel like it's worth mentioning icanhazip.com [0] as well, since it's now run by Cloudflare [1]. Until recently switching to a custom CF worker, that's been by go-to for ages. [0]: https://www.icanhazip.com/ https://www.icanhazip.com/ [1]: https://major.io/p/a-new-future-for-icanhazip/ https://major.io/p/a-new-future-for-icanhazip/
- noname120 2y ago
  Does Cloudflare have a history of sunsetting products they've bought? Acquisitions by Google, Apple, Meta, etc. are yellow flags that the product may cease to exist soon. I wonder if Cloudflare has a better track record in that regard.
  - godzillabrennus 2y ago
    No one sunsets products like Google. I’m in the middle of transferring all my domains from Squarespace thanks to Googles sale of that business to that incredibly lousy vendor.
    - CSSer 2y ago
      Ugh, same. You’re right. Nothing is safe at Google or even a safe bet with Google. Look at third-party cookies. I can’t believe there isn’t outrage in the streets over the fact that they beat that drum for four straight years and now they suddenly have a change of heart. At some point their rationale has to become irrelevant. It’s simply unprofessional behavior.
      - b0ner_t0ner 2y ago
        > Nothing is safe at Google Google Ads
        CSSer 2y ago
        This narrative might be shifting in realtime with the LLM race and privacy wars. How do I advertise in Gemini? Do Google users want me to? I’ve worked in and around digital advertising and marketing for the better part of a decade. We look at Google with all the admiration one would have for a pet crocodile.
chickenballs 2y ago
You could host your own VPS for a few dollars specifically for the purpose of responding back to you with your own residential IP. But that wouldn’t be free. In my experience, you have to be careful if relying on one IP source because if they give you the wrong one, then your servers could be MITM’d. I say this because I have a script which does this exact thing, and found a couple of these ‘what’s my ip’ services giving me someone else’s IP. Because of that, I randomly select a few IP addresses and ensure they are identical before I trust any of them.
deleted 2y ago
[deleted]
fullspectrumdev 2y ago
Kind of, you can use the CF CDN to grab an external IP by using any CF site. Example: https://www.fullspectrum.dev/a-less-suspect-way-to-get-external-ips-thanks-to-cloudflare/ https://www.fullspectrum.dev/a-less-suspect-way-to-get-exter...
genewitch 2y ago
there's a way to tell caddy server to host its own access.log So you have some junk VPS or whatever that just has caddy hosting its log with an easy to remember domain (they're cheap enough), and you go like "curl http://easydomain.com/idreallylikemyip http://easydomain.com/idreallylikemyip" and then once more: curl http://easydomain.com/N http://easydomain.com/N | grep "idreallylikemyip" the code that used to work is on my github, i uploaded it there a week or two ago. Someone who needs a way to find out the public ipv4 of any device not just their own can probably figure out how to get it to work again!
- dathery 2y ago
  You can have Caddy return the user's IP address directly: https://caddy.community/t/caddy-server-that-returns-only-ip-address-as-text/6928 https://caddy.community/t/caddy-server-that-returns-only-ip-... Similar things are also possible with nginx and Apache.
  - genewitch 2y ago
    this was implemented in 2018, but it is good to know. it also doubled as a dumb way to pass messages between hosts.
deleted 2y ago
[deleted]
BasiliusCarver 2y ago
I’ve used this: dig @1.1.1.1 ch txt whoami.cloudflare +short
- codetrotter 2y ago
  That's pretty neat! And they offer a similar service on their DNS resolver over IPv6. This page lists the IPv6 addresses to use when connecting to their resolver over IPv6 https://developers.cloudflare.com/1.1.1.1/ip-addresses/ https://developers.cloudflare.com/1.1.1.1/ip-addresses/ and with that I just tried dig @2606:4700:4700::1111 ch txt whoami.cloudflare +short And it works, returning the IPv6 address that the request came from :)

teamspirit 2y ago

https://www.cloudflare.com/cdn-cgi/trace https://www.cloudflare.com/cdn-cgi/trace will return your ip.

mxuribe 2y ago
The (above) shared url leveraging the cloudflare.com domain name seems to show ip v6 address, while I've noticed that the following defaults to showing ip v4 address: https://1.1.1.1/cdn-cgi/trace https://1.1.1.1/cdn-cgi/trace Pick your poison as you wish - either is great! :-)
- codetrotter 2y ago
  I’d pick the one that supports IPv6 and then make two separate requests to it. One request over IPv4 and one over IPv6. curl -4 https://www.cloudflare.com/cdn-cgi/trace curl -6 https://www.cloudflare.com/cdn-cgi/trace Also the reason that the 1.1.1.1 one shows only IPv4 address is because 1.1.1.1 is itself an IPv4 address. So any connection to it will have to be using IPv4.
  - tcfhgj 2y ago
    could you not retrieve your ipv6 directly from the system?
    - codetrotter 2y ago
      Yes, but getting it in a response from an external server means I don’t have to be specific about which interface to get the IPv6 address of and so on.
      - tcfhgj 2y ago
        the same specific interface used to contact the external server
        wizzwizz4 2y ago
        i.e., an arbitrarily-selected interface capable of reaching Cloudflare.
        codetrotter 2y ago
        Which is neatly abstracted away so you don’t have to think about it unless you want to. And therefore reaching out to an external server and having it say where the request came from is the path of least resistance for a script that can work across different hosts with minimal machine specific configuration. Listen, if you want to check the IPv6 address from the interface list go ahead I’m not trying to stop you. But because I anyway need to reach a third party to know my own IPv4 address then yeah when that third party can also tell me IPv6 address I’m gonna do it that way.
        graton 2y ago
        That requires running it on the router/device which gets the public IP address. By using the service you can update your DNS IP address on a system that is behind the router.
        tcfhgj 2y ago
        What do you mean? Every device gets a public ipv6 (usually).
        graton 2y ago
        I have a router connected to the internet, it gets the public IP address. The router is connected to the internal network in my home and has the IP address of 192.168.1.1. Behind the router is my computer which has a non-public IP address, for example 192.168.1.2. My computer is the one I want to run the program to update the DNS entry. My computer does not know what the public IP address is by looking at its interfaces.
macote 2y ago
This is how I use it in my bash script: current_ip=$(curl -s -X GET https://1.1.1.1/cdn-cgi/trace | grep -Po "(?<=ip=)(.*)")
- networked 2y ago
  I find awk more clear for this kind of job. You can replace grep -Po "(?<=ip=)(.*)" with awk -F= '$1 == "ip" { print $2 }'
  - macote 2y ago
    Thanks for that, I agree.
immibis 2y ago
Works on every cloudflare-MITMed domain btw.

victorbjorklund 2y ago

You could do it with a cloudflare worker that just returns the ip address of the request

victorbjorklund 2y ago
Nevermind. The other answer is better

gothink 2y ago

I feel like it's worth mentioning icanhazip.com [0] as well, since it's now run by Cloudflare [1]. Until recently switching to a custom CF worker, that's been by go-to for ages. [0]: https://www.icanhazip.com/ https://www.icanhazip.com/ [1]: https://major.io/p/a-new-future-for-icanhazip/ https://major.io/p/a-new-future-for-icanhazip/

noname120 2y ago
Does Cloudflare have a history of sunsetting products they've bought? Acquisitions by Google, Apple, Meta, etc. are yellow flags that the product may cease to exist soon. I wonder if Cloudflare has a better track record in that regard.
- godzillabrennus 2y ago
  No one sunsets products like Google. I’m in the middle of transferring all my domains from Squarespace thanks to Googles sale of that business to that incredibly lousy vendor.
  - CSSer 2y ago
    Ugh, same. You’re right. Nothing is safe at Google or even a safe bet with Google. Look at third-party cookies. I can’t believe there isn’t outrage in the streets over the fact that they beat that drum for four straight years and now they suddenly have a change of heart. At some point their rationale has to become irrelevant. It’s simply unprofessional behavior.
    - b0ner_t0ner 2y ago
      > Nothing is safe at Google Google Ads
      - CSSer 2y ago
        This narrative might be shifting in realtime with the LLM race and privacy wars. How do I advertise in Gemini? Do Google users want me to? I’ve worked in and around digital advertising and marketing for the better part of a decade. We look at Google with all the admiration one would have for a pet crocodile.

chickenballs 2y ago

You could host your own VPS for a few dollars specifically for the purpose of responding back to you with your own residential IP. But that wouldn’t be free. In my experience, you have to be careful if relying on one IP source because if they give you the wrong one, then your servers could be MITM’d. I say this because I have a script which does this exact thing, and found a couple of these ‘what’s my ip’ services giving me someone else’s IP. Because of that, I randomly select a few IP addresses and ensure they are identical before I trust any of them.

deleted 2y ago

[deleted]

fullspectrumdev 2y ago

Kind of, you can use the CF CDN to grab an external IP by using any CF site. Example: https://www.fullspectrum.dev/a-less-suspect-way-to-get-external-ips-thanks-to-cloudflare/ https://www.fullspectrum.dev/a-less-suspect-way-to-get-exter...

genewitch 2y ago

there's a way to tell caddy server to host its own access.log So you have some junk VPS or whatever that just has caddy hosting its log with an easy to remember domain (they're cheap enough), and you go like "curl http://easydomain.com/idreallylikemyip http://easydomain.com/idreallylikemyip" and then once more: curl http://easydomain.com/N http://easydomain.com/N | grep "idreallylikemyip" the code that used to work is on my github, i uploaded it there a week or two ago. Someone who needs a way to find out the public ipv4 of any device not just their own can probably figure out how to get it to work again!

dathery 2y ago
You can have Caddy return the user's IP address directly: https://caddy.community/t/caddy-server-that-returns-only-ip-address-as-text/6928 https://caddy.community/t/caddy-server-that-returns-only-ip-... Similar things are also possible with nginx and Apache.
- genewitch 2y ago
  this was implemented in 2018, but it is good to know. it also doubled as a dumb way to pass messages between hosts.

deleted 2y ago

[deleted]

BasiliusCarver 2y ago

I’ve used this: dig @1.1.1.1 ch txt whoami.cloudflare +short

codetrotter 2y ago
That's pretty neat! And they offer a similar service on their DNS resolver over IPv6. This page lists the IPv6 addresses to use when connecting to their resolver over IPv6 https://developers.cloudflare.com/1.1.1.1/ip-addresses/ https://developers.cloudflare.com/1.1.1.1/ip-addresses/ and with that I just tried dig @2606:4700:4700::1111 ch txt whoami.cloudflare +short And it works, returning the IPv6 address that the request came from :)