Files
coredns/core/dnsserver/onstartup.go
Catena cyber 625f6c9307 perf: avoid string concatenation in loops (#7572)
* perf: avoid string concatenation in loops

Apply perfpsrint linter

Signed-off-by: Philippe Antoine <contact@catenacyber.fr>

* ci: enable perfsprint

Signed-off-by: Philippe Antoine <contact@catenacyber.fr>

---------

Signed-off-by: Philippe Antoine <contact@catenacyber.fr>
2025-10-06 00:05:58 -07:00

58 lines
1.6 KiB
Go

package dnsserver
import (
"fmt"
"regexp"
"sort"
"strings"
"github.com/coredns/coredns/plugin/pkg/dnsutil"
)
// checkZoneSyntax() checks whether the given string match 1035 Preferred Syntax or not.
// The root zone, and all reverse zones always return true even though they technically don't meet 1035 Preferred Syntax
func checkZoneSyntax(zone string) bool {
if zone == "." || dnsutil.IsReverse(zone) != 0 {
return true
}
regex1035PreferredSyntax, _ := regexp.MatchString(`^(([A-Za-z]([A-Za-z0-9-]*[A-Za-z0-9])?)\.)+$`, zone)
return regex1035PreferredSyntax
}
// startUpZones creates the text that we show when starting up:
// grpc://example.com.:1055
// example.com.:1053 on 127.0.0.1
func startUpZones(protocol, addr string, zones map[string][]*Config) string {
keys := make([]string, len(zones))
i := 0
for k := range zones {
keys[i] = k
i++
}
sort.Strings(keys)
var sb strings.Builder
for _, zone := range keys {
if !checkZoneSyntax(zone) {
sb.WriteString(fmt.Sprintf("Warning: Domain %q does not follow RFC1035 preferred syntax\n", zone))
}
// split addr into protocol, IP and Port
_, ip, port, err := SplitProtocolHostPort(addr)
if err != nil {
// this should not happen, but we need to take care of it anyway
sb.WriteString(fmt.Sprintln(protocol + zone + ":" + addr))
continue
}
if ip == "" {
sb.WriteString(fmt.Sprintln(protocol + zone + ":" + port))
continue
}
// if the server is listening on a specific address let's make it visible in the log,
// so one can differentiate between all active listeners
sb.WriteString(fmt.Sprintln(protocol + zone + ":" + port + " on " + ip))
}
return sb.String()
}