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by gwu78 4538 days ago
Your claim was they are proxying "all" port 53 traffic.

In effect, you are saying no customer can query any DNS server except Shaw's.

That sounds a bit extreme.

I have more questions. Can you run some tests?

You say you use DNSCrypt. Can you try it with port 53? Maybe something like

  dnscrypt-proxy --resolver-port=53
and

  dnscrypt-proxy --resolver-port=53 --tcp-only
DNSCrypt is built using public domain software written by a maths professor: namely, djbdns and curvecp.

Now, without DNSCrypt, can you try using djbdns? For me at least, it is easier to understand what the software does. dig and the BIND libraries are far too complex for my liking.

Compile or get binaries for djbdns and use dnsq(1).

  dnsq a news.ycombinator.com 31.13.75.17
If you get no response immediately, wait at least 60 seconds for a time out.

Finally, compile or get binaries for drill(1) from NLnet Labs.

  drill -t news.ycombinator.com @31.13.75.17

  echo ". 1 in ns a.root.servers.net." > 1.tmp
  echo "a.root.servers.net. 1 a 198.41.0.4" >> 1.tmp

  echo > 2.tmp

  drill -4ord -r1.tmp -tc2.tmp news.ycombinator.com @31.13.75.17
I'm genuinely curious about your situation. Shaw is no doubt playing games with their DNS, but I'm still not convinced they are "proxy[ing] all port 53 traffic".

I know that some ISP's block all traffic sent to port 25. But they have a compelling reason and hence a justification for doing that. Not true with proxying traffic to port 53. There's no harm in customers using DNS servers besides Shaw's.
1 comments
aendruk 4537 days ago
I've done some more tests [1] as you suggested. It looks like Shaw is routing all UDP/53 traffic to their DNS servers; I'd not considered TCP earlier. My optimistic guess as to their motivation for using such an invasive technique is that it was easy for them to deploy.

  [1]: https://gist.github.com/0998a0dd2c0abca91c8b
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gwu78 4535 days ago
Personally, I do not use DNS much at all except to do periodic bulk lookups for new domains I might visit.

I store all the DNS info I'll ever use[1] in .cdb files and also in my /etc/hosts file.

I do this for speed reasons, because HOSTS or tinydns on 127.xxx.xxx.xxx is always faster than DNS. But if I had an ISP like yours, it would be a necessity for other reasons.

Shaw is actually interfering with their customers' ability to lookup IP numbers. This is the most basic of all internet services.

And no one is complaining?

Anyway, you could do bulk lookups with TCP and then store the DNS info locally. That could reduce if not elimibate your need for DNS.

I've always thought that there should be DNS servers that can handle pipelined TCP queries, and this is one reason why.

If the idea of bulk lookups and not using DNS otherwise sounds intriguing and you want some examples of scripts to do bulk lookups, e.g. for HN sites, let me know. It sounds like you could really benefit from reducing your dependence on DNS.

1. For example, all the IP addresses for sites that appear on HN.

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