consul/agent/dns_oss.go

87 lines
2.4 KiB
Go

// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1
//go:build !consulent
// +build !consulent
package agent
import (
"fmt"
"github.com/hashicorp/consul/acl"
"github.com/hashicorp/consul/agent/config"
)
type enterpriseDNSConfig struct{}
func getEnterpriseDNSConfig(conf *config.RuntimeConfig) enterpriseDNSConfig {
return enterpriseDNSConfig{}
}
// parseLocality can parse peer name or datacenter from a DNS query's labels.
// Peer name is parsed from the same query part that datacenter is, so given this ambiguity
// we parse a "peerOrDatacenter". The caller or RPC handler are responsible for disambiguating.
func (d *DNSServer) parseLocality(labels []string, cfg *dnsConfig) (queryLocality, bool) {
locality := queryLocality{
EnterpriseMeta: d.defaultEnterpriseMeta,
}
switch len(labels) {
case 2, 4:
// Support the following formats:
// - [.<datacenter>.dc]
// - [.<peer>.peer]
for i := 0; i < len(labels); i += 2 {
switch labels[i+1] {
case "dc":
locality.datacenter = labels[i]
case "peer":
locality.peer = labels[i]
default:
return queryLocality{}, false
}
}
// Return error when both datacenter and peer are specified.
if locality.datacenter != "" && locality.peer != "" {
return queryLocality{}, false
}
return locality, true
case 1:
return queryLocality{peerOrDatacenter: labels[0]}, true
case 0:
return queryLocality{}, true
}
return queryLocality{}, false
}
type querySameness struct{}
// parseSamenessGroupLocality wraps parseLocality in OSS
func (d *DNSServer) parseSamenessGroupLocality(cfg *dnsConfig, labels []string, errfnc func() error) ([]queryLocality, error) {
locality, ok := d.parseLocality(labels, cfg)
if !ok {
return nil, errfnc()
}
return []queryLocality{locality}, nil
}
func serviceCanonicalDNSName(name, kind, datacenter, domain string, _ *acl.EnterpriseMeta) string {
return fmt.Sprintf("%s.%s.%s.%s", name, kind, datacenter, domain)
}
func nodeCanonicalDNSName(lookup serviceLookup, nodeName, respDomain string) string {
if lookup.PeerName != "" {
// We must return a more-specific DNS name for peering so
// that there is no ambiguity with lookups.
return fmt.Sprintf("%s.node.%s.peer.%s",
nodeName,
lookup.PeerName,
respDomain)
}
// Return a simpler format for non-peering nodes.
return fmt.Sprintf("%s.node.%s.%s", nodeName, lookup.Datacenter, respDomain)
}