CIDR query routing (#1159)

* core: allow all CIDR ranges in zone specifications

Allow (e.g.) a v4 reverse on a /17. If a zone is specified in such a
way a FilterFunc is set in the config. This filter is checked against
incoming queries.

For all other queries this adds a 'x != nil' check which will not impact
performace too much. Benchmark function is added as well to check for
this as wel.

Add multiple tests in tests/server_reverse_test.go.

Benchmark shows in the non-reverse case this hardly impact the speed:

~~~
classless:
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4   	 1000000	      1431 ns/op	      16 B/op	       1 allocs/op

pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4   	 1000000	      1429 ns/op	      16 B/op	       1 allocs/op

master:
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4   	 1000000	      1412 ns/op	      16 B/op	       1 allocs/op

pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4   	 1000000	      1429 ns/op	      16 B/op	       1 allocs/op
~~~

* README.md updates
This commit is contained in:
Miek Gieben
2017-10-24 10:16:03 +01:00
committed by GitHub
parent 5f813bcc21
commit fcd0342e42
15 changed files with 269 additions and 120 deletions

View File

@@ -155,9 +155,11 @@ IP addresses are also allowed. They are automatically converted to reverse zones
~~~
Means you are authoritative for `0.0.10.in-addr.arpa.`.
The netmask must be dividable by 8, if it is not the reverse conversion is not done. This also works
for IPv6 addresses. If for some reason you want to serve a zone named `10.0.0.0/24` add the closing
dot: `10.0.0.0/24.` as this also stops the conversion.
This also works for IPv6 addresses. If for some reason you want to serve a zone named `10.0.0.0/24`
add the closing dot: `10.0.0.0/24.` as this also stops the conversion.
This even works for CIDR (See RFC 1518 and 1519) addressing, i.e `10.0.0.0/25`, CoreDNS will then
check if the `in-addr` request falls in the correct range.
Listening on TLS and for gRPC? Use: