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DNS Toys (2022)

dns.toys

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Re: DNS Toys (2022)

#61

Post by m3047 »

ricardo81 wrote: post #59
m3047 wrote: post #51

Earlier quoted context omitted.

Don't use the word "abuse" unless it's in the sense of "SOAP and XHR are an 'abuse' of HTTP". The IN (internet) class is the evolutionary "towering cedar" of the moment, but there were the CH (chaos) and HS (hesiod) classes during the cambrian period; you might review those project's purposes and goals. Arguably the abuse today is in the form of things like ten millisecond windows for retransmission and qname minimiz…

Fair point. Probably showing my lack of experience previous to the millennium, at most it was debugging res_mkquery for hours because of what I was passing as a class, iirc C_ANY rather than C_IN.

ANY is definitely a trap for the overconfident, as it is a qtype without a corresponding rdtype. Is there a wildcard for class? You got me there, I'd have to go look it up and I'm up to my armpits in something else at the moment.

Re: DNS Toys (2022)

#64

Post by brianzelip »

m3047 wrote: post #51
ricardo81 wrote: post #26

Somewhat related, DNS lookup for (UK) business listings - same idea of 'abusing' the DNS service to provide non-DNS data. https://www.num.uk/ Though going by their roadmap, it may be they're no longer maintaining the service.

Don't use the word "abuse" unless it's in the sense of "SOAP and XHR are an 'abuse' of HTTP". The IN (internet) class is the evolutionary "towering cedar" of the moment, but there were the CH (chaos) and HS (hesiod) classes during the cambrian period; you might review those project's purposes and goals. Arguably the abuse today is in the form of things like ten millisecond windows for retransmission and qname minimiz…

The dns toys author himself referred to it as "abusing dns" in the talk linked from another comment here, https://www.youtube.com/watch?v=ANmFZ8rbmnc.

Re: DNS Toys (2022)

#65

Post by micheljansen »

mejthemage wrote: post #41

I didn't know you could specify a DNS server with a name. So does dig first look up that name using whatever DNS server is normally configured to determine where the intended DNS server is? NextDNS gives you a name that you can put in certain UIs (like "Private DNS" in Android) -- I always assumed there was just something special about those.

Almost. Every domain (or rather “zone”) has an authoritative name server that maintains the dns records for that zone. When you perform a lookup from your device, it will ask your configured name server (from your ISP or 8.8.8.8 and friends), which will then look up the authoritative server and contact it to resolve the answer and send back the result (which it caches).

You can tell dig to bypass the normal way of things and ask a specific name server instead. This can be useful to bypass caches and debug DNS issues.

Re: DNS Toys (2022)

#66

Post by baranul »

johnhenry wrote: post #39

I'm a big fan of Julia Evans[1] who's made a number of useful toys including ones for DNS here[2] and here[3]. - [1] https://jvns.ca/ - [2] https://dns-lookup.jvns.ca/ - [3] https://messwithdns.net/

[dead]

Re: DNS Toys (2022)

#67

Post by 1vuio0pswjnm7 »

koito17 wrote: post #5

This reminds me of a neat little trick I used back then to "reliably" compute IP address of my machines for a dynamic DNS utility I wrote for myself. OpenDNS resolvers (such as resolver1.opendns.com) will resolve myip.opendns.com to your actual IP address. Whether you get A or AAAA records depends on your connection. Since the IP addresses for these resolvers tend to be anycast IPs, I also want to believe they are ma…

What's more likely to go down. OpenDNS or YouTube.

    curl -4si0A "" https://www.youtube.com|sed -n '/ip=/{s/.*ip=//;s/\.*//p;};'|uniq
What's more likely to go down. OpenDNS or Cloudflare.

This will work with any Cloudflare IP address and it does not even require TLS.

    printf 'GET /cdn-cgi/trace HTTP/1.0\r\nHost: cloudflare.com |nc -vvn  104.18.25.13 80 |sed -n /ip=/p
To get list of Cloudflare IPs

    curl -4si0A ""  https://api.cloudflare.com/client/v4/ips
There are many, many websites that print the client IP address in a webpage or in a HTTP head. Not necessarily "What is my IP" websites. No need to rely on just one source.

Websites that use Cloudlfare to block certain requests are another option. For example, StackOverflow. Just send HTTP request without User-Agent header.

     curl -si40A "" http://stackoverflow.com|sed -n '/cf-footer-ip">/{s/.*">//;s/
The success of "What is my IP" websites is quite surprising given that one's IP address is displayed by hundreds of thousands of other websites.

Further reading on utility of DNS

https://www.netmeister.org/blog/dns-rrs.html

Re: DNS Toys (2022)

#68

Post by devilsAdv0cate »

1vuio0pswjnm7 wrote: post #67
koito17 wrote: post #5

This reminds me of a neat little trick I used back then to "reliably" compute IP address of my machines for a dynamic DNS utility I wrote for myself. OpenDNS resolvers (such as resolver1.opendns.com) will resolve myip.opendns.com to your actual IP address. Whether you get A or AAAA records depends on your connection. Since the IP addresses for these resolvers tend to be anycast IPs, I also want to believe they are ma…

What's more likely to go down. OpenDNS or YouTube. curl -4si0A "" https://www.youtube.com|sed -n '/ip=/{s/.*ip=//;s/\.*//p;};'|uniq What's more likely to go down. OpenDNS or Cloudflare. This will work with any Cloudflare IP address and it does not even require TLS. printf 'GET /cdn-cgi/trace HTTP/1.0\r\nHost: cloudflare.com |nc -vvn 104.18.25.13 80 |sed -n /ip=/p To get list of Cloudflare IPs curl -4si0A "" https://a…

[dead]

Re: DNS Toys (2022)

#69

Post by m3047 »

brianzelip wrote: post #64
m3047 wrote: post #51

Earlier quoted context omitted.

Don't use the word "abuse" unless it's in the sense of "SOAP and XHR are an 'abuse' of HTTP". The IN (internet) class is the evolutionary "towering cedar" of the moment, but there were the CH (chaos) and HS (hesiod) classes during the cambrian period; you might review those project's purposes and goals. Arguably the abuse today is in the form of things like ten millisecond windows for retransmission and qname minimiz…

The dns toys author himself referred to it as "abusing dns" in the talk linked from another comment here, https://www.youtube.com/watch?v=ANmFZ8rbmnc .

Fetish for pearl clutchers; prove me wrong.

Re: DNS Toys (2022)

#70

Post by m3047 »

brianzelip wrote: post #64
m3047 wrote: post #51

Earlier quoted context omitted.

Don't use the word "abuse" unless it's in the sense of "SOAP and XHR are an 'abuse' of HTTP". The IN (internet) class is the evolutionary "towering cedar" of the moment, but there were the CH (chaos) and HS (hesiod) classes during the cambrian period; you might review those project's purposes and goals. Arguably the abuse today is in the form of things like ten millisecond windows for retransmission and qname minimiz…

The dns toys author himself referred to it as "abusing dns" in the talk linked from another comment here, https://www.youtube.com/watch?v=ANmFZ8rbmnc .

I watched the video. He's trolling his hypothesized pearl clutchers. I'm sure I share the same critics. Actually most of the talk is open source intelligence basics and utilization of DNS for nonpublic purposes.

Good sell regarding hotel networks as adversaries. :-p

It's time. Start the long walk. We are migrating to meet the skexies, you're welcome to join us.

"Toy server" with 6 million queries and the talk is not about keeping the server up. We're done here; you can find the mike somewhere on the floor.

He has a fondness for finger.

That's my kindness.

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