mirror of
https://github.com/coredns/coredns.git
synced 2025-10-31 02:03:20 -04:00
32 lines
684 B
Go
32 lines
684 B
Go
|
package request
|
||
|
|
|
||
|
|
import (
|
||
|
|
"github.com/coredns/coredns/plugin/pkg/edns"
|
||
|
|
|
||
|
|
"github.com/miekg/dns"
|
||
|
|
)
|
||
|
|
|
||
|
|
func supportedOptions(o []dns.EDNS0) []dns.EDNS0 {
|
||
|
|
var supported = make([]dns.EDNS0, 0, 3)
|
||
|
|
// For as long as possible try avoid looking up in the map, because that need an Rlock.
|
||
|
|
for _, opt := range o {
|
||
|
|
switch code := opt.Option(); code {
|
||
|
|
case dns.EDNS0NSID:
|
||
|
|
fallthrough
|
||
|
|
case dns.EDNS0EXPIRE:
|
||
|
|
fallthrough
|
||
|
|
case dns.EDNS0COOKIE:
|
||
|
|
fallthrough
|
||
|
|
case dns.EDNS0TCPKEEPALIVE:
|
||
|
|
fallthrough
|
||
|
|
case dns.EDNS0PADDING:
|
||
|
|
supported = append(supported, opt)
|
||
|
|
default:
|
||
|
|
if edns.SupportedOption(code) {
|
||
|
|
supported = append(supported, opt)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return supported
|
||
|
|
}
|