rip

README

RIP

A simple DNS server that extracts IP address (or cname) from the requested domain name and sends it back in the response.

Encoding rules

Since RIP extracts the response from the request, it's important to understand the encoding rules. RIP has three kinds of entities:

• rr - something that generate response (e.g. IP, CNAME and so on):

    <IP> - returns IP address (guesses IPv4/IPv6)
    <IPv4>.[4|v4] - strictly returns IPv4 address only
    <IPv6>.[6|v6] - strictly returns IPv6 address only
    <cname>.[c|cname]  - return CNAME record with <cname>
    <target>.[p|proxy] - resolve <target> name and returns it

• container - something that holds rr's (or another container), picked one on each request and response with it:

    <rr>.<container>.[r|random] - pick random rr/container
    <rr>.<container>.[l|loop] - iterate over rr/container
    <rr1>.<rr0>.[s|sticky] - alias for loop container: <rr1-ttl-30>.<rr0-cnt-1>.l

• limit modifier - something that limit this kind of responses:

    cnt-<num> - use rr <num> requests. e.g.:
      * 1-1-1-1.v4-cnt-10 - returns 1.1.1.1 10 times 
    ttl-<duration> - use rr <duration> duration:
      * 2-2-2-2.v4-ttl-20s - returns 2.2.2.2 20 seconds from first v4-rr response

Also, RIP allowing to use any prefixes (see examples below).

IP address format

IP address can be presented in two variants - dash-delimited and base16-form. For example, ips 0a000001 and 10-0-0-1 are equal and points to 10.0.0.1 You can also use the built-in converter to encode IP address:

$ rip encode fe80::fa94:c2ff:fee5:3cf6 127.0.0.1
fe80000000000000fa94c2fffee53cf6	7f000001

Usage

Run NS server for zone example.com with default IP 77.88.55.70 and 2a02:6b8: a:: a:

$ rip ns --zone=example.com --ipv4=77.88.55.70 --ipv6=2a02:6b8:a::a

When requesting it, we should get the following responses:

# IPv4
    1-1-1-1.example.com ->  1.1.1.1 
    1-1-1-1.v4.example.com ->  1.1.1.1 
    foo.1-1-1-1.v4.example.com ->  1.1.1.1
    bar.foo.1-1-1-1.v4.example.com ->  1.1.1.1
    1010101.v4.example.com -> 1.1.1.1

# IPv6
    2a01-7e01--f03c-91ff-fe3b-c9ba.example.com    ->  2a01:7e01::f03c:91ff:fe3b:c9ba
    2a01-7e01--f03c-91ff-fe3b-c9ba.v6.example.com    ->  2a01:7e01::f03c:91ff:fe3b:c9ba
    2a017e0100000000f03c91fffe3bc9ba.v6.example.com -> 2a017e0100000000f03c91fffe3bc9ba
    foo.2a01-7e01--f03c-91ff-fe3b-c9ba.v6.example.com    -> 2a01:7e01::f03c:91ff:fe3b:c9ba
    foo.--1.6.example.com   ->  ::1

# Random
    0a000002.0a000001.random.example.com ->  random between 10.0.0.1 and 10.0.0.2
    0a000003.0a000002.0a000001.random.example.com ->  random between 10.0.0.1 and 10.0.0.2

# Loop
    8ba299a7.8ba299a8.loop.example.com ->  loop over 139.162.153.168 and 139.162.153.167
    8ba299a7.v4-ttl-5s.8ba299a8.v4-cnt-5.loop.example.com ->  139.162.153.168 (first 5 requests), then 139.162.153.167 (next 5s), then 139.162.153.168 (next 5 requests), and so on
    8ba299a7.v4-ttl-5s.b32-onxw2zlunbuw4zzomnxw63bnmnxs44tv.c-cnt-5.loop.example.com ->  CNAME "something.cool.co.ru." (first 5 requests), then 139.162.153.167 (next 5s), CNAME "something.cool.co.ru." (first 5 requests), and so on
    8ba299a6.v4.8ba299a7.v4.loop-ttl-5s.8ba299a8.v4-cnt-5.loop.example.com ->  139.162.153.168 (first 5 requests), then 139.162.153.167/139.162.153.166 (next 5s), then 139.162.153.168 (next 5 requests) and so on

# Sticky
    8ba299a7.8ba299a8.s.example.com ->  139.162.153.168 (first A request) then 139.162.153.167 (30s), then 139.162.153.168 (next A request) and so on

# Cname
    ya-ru.c.example.com ->  canonical name ya.ru
    google-com.c.example.com ->  canonical name google.com
    b32-onxw2zlunbuw4zzomnxw63bnmnxs44tv.c.example.com ->  canonical name something.cool.co.ru

# Proxy
    ya-ru.p.example.com ->  87.250.250.242 and 2a02:6b8::2:242
    google-com.p.example.com  ->  64.233.164.102 and 2a00:1450:4010:c07::64