customize max sub domain length

[patterniha]

Currently, most of DNS IPs do not work in Iran, according to tests, this is for two reasons:

1. GFW changes the subdomain capitalization:

Randomly capitalizes some letters and lowercases others in request subdomain.
for example: abcdefgh.example.com is converted to aBcDEfgH.example.com
It doesn't affect normal dns requests to big dns providers like Cloudflare, because Cloudflare is not case sensitive.
Fortunately, unlike slipstream-C, slipstream-rust is case-insensitive and doesn't have this problem.

2. GFW limit subdomain length:

for example according to @FDeghy tests:

OXNWZGDTUGNGFBUALMDSYTLGAU6B5Z4XPJBXWUJHIYBBWL6MNZSVLMVEX.DYYJQ2LODHWG3JIBKHBTLLYVPP.abc.aaaaaaaaaa.ir (102 total length)

doesn't reach the server, but

OXNWZGDTUGNGFBUALMDSYTLGAU6B5Z4XPJBXWUJHIYBBWL6MNZSVLMVEX.DYYJQ2LODHWG3JIBKHBTLLYVP.abc.aaaaaaaaaa.ir (101 total length)

reaches the server.

///

so we need a option to control max total subdomain length.

This is an urgent need for Iranians. This is happening to most of the DNS Ips, and right now the only way to access the internet is DNS-tunnel.

[patterniha]

@Mygod

We need your help quickly. We may be disconnected from the world at any moment (like other 99.99% of Iranian people)

A blatant human rights violation has occurred in Iran, and the internet is broken for 99.99% of the people for 6 days (after they killed 12000 people)

[Mygod]

Feel free to check #3. I haven't tested it yet.

[Mygod]

Also what do you mean by total subdomain length? Did you also test this with different domains?

[patterniha]

for example total length of a.b.c.com is 9, we should have control of the max

[patterniha]

currently only max=101 is allowed

[Mygod]

Did you try #3? It should probably resolve your concern for now although I am planning to rewrite that later.

[patterniha]

thank you very much, i will test.

[patterniha]

according to new tests, we don't have a length-limit, we have rate-limit !

so there is no need to limit the domain length

[patterniha]

unfortunately, length limit still exists, most DNS allow only maximum of 101 domain length.

also, it seems that we have no rate limit when source ports of requests are different.

[Mygod]

Okay, which one is more important? Length limit or different source ports?