mirror of https://github.com/status-im/consul.git
652 lines
25 KiB
Go
652 lines
25 KiB
Go
// Copyright (c) HashiCorp, Inc.
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// SPDX-License-Identifier: BUSL-1.1
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package dns
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import (
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"encoding/hex"
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"fmt"
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"net"
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"strings"
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"time"
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"github.com/miekg/dns"
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"github.com/hashicorp/consul/agent/discovery"
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"github.com/hashicorp/consul/agent/structs"
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"github.com/hashicorp/consul/internal/dnsutil"
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)
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// messageSerializer is the high level orchestrator for generating the Answer,
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// Extra, and Ns records for a DNS response.
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type messageSerializer struct{}
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// serializeOptions are the options for serializing a discovery.Result into a DNS message.
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type serializeOptions struct {
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req *dns.Msg
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reqCtx Context
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query *discovery.Query
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results []*discovery.Result
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resp *dns.Msg
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cfg *RouterDynamicConfig
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responseDomain string
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remoteAddress net.Addr
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maxRecursionLevel int
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dnsRecordMaker dnsRecordMaker
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translateAddressFunc func(dc string, addr string, taggedAddresses map[string]string, accept dnsutil.TranslateAddressAccept) string
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translateServiceAddressFunc func(dc string, address string, taggedAddresses map[string]structs.ServiceAddress, accept dnsutil.TranslateAddressAccept) string
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resolveCnameFunc func(cfgContext *RouterDynamicConfig, name string, reqCtx Context, remoteAddress net.Addr, maxRecursionLevel int) []dns.RR
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}
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// serializeQueryResults converts a discovery.Result into a DNS message.
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func (d messageSerializer) serialize(opts *serializeOptions) (*dns.Msg, error) {
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resp := new(dns.Msg)
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resp.SetReply(opts.req)
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resp.Compress = !opts.cfg.DisableCompression
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resp.Authoritative = true
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resp.RecursionAvailable = canRecurse(opts.cfg)
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opts.resp = resp
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qType := opts.req.Question[0].Qtype
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reqType := parseRequestType(opts.req)
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// Always add the SOA record if requested.
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if qType == dns.TypeSOA {
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resp.Answer = append(resp.Answer, opts.dnsRecordMaker.makeSOA(opts.responseDomain, opts.cfg))
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}
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switch {
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case qType == dns.TypeSOA, reqType == requestTypeAddress:
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for _, result := range opts.results {
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for _, port := range getPortsFromResult(result) {
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ans, ex, ns := d.getAnswerExtraAndNs(serializeToGetAnswerExtraAndNsOptions(opts, result, port))
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resp.Answer = append(resp.Answer, ans...)
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resp.Extra = append(resp.Extra, ex...)
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resp.Ns = append(resp.Ns, ns...)
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}
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}
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case qType == dns.TypeSRV:
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handled := make(map[string]struct{})
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for _, result := range opts.results {
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for _, port := range getPortsFromResult(result) {
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// Avoid duplicate entries, possible if a node has
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// the same service the same port, etc.
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// The datacenter should be empty during translation if it is a peering lookup.
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// This should be fine because we should always prefer the WAN address.
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address := ""
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if result.Service != nil {
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address = result.Service.Address
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} else {
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address = result.Node.Address
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}
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tuple := fmt.Sprintf("%s:%s:%d", result.Node.Name, address, port.Number)
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if _, ok := handled[tuple]; ok {
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continue
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}
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handled[tuple] = struct{}{}
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ans, ex, ns := d.getAnswerExtraAndNs(serializeToGetAnswerExtraAndNsOptions(opts, result, port))
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resp.Answer = append(resp.Answer, ans...)
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resp.Extra = append(resp.Extra, ex...)
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resp.Ns = append(resp.Ns, ns...)
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}
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}
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default:
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// default will send it to where it does some de-duping while it calls getAnswerExtraAndNs and recurses.
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d.appendResultsToDNSResponse(opts)
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}
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if opts.query != nil && opts.query.QueryType != discovery.QueryTypeVirtual &&
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len(resp.Answer) == 0 && len(resp.Extra) == 0 {
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return nil, discovery.ErrNoData
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}
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return resp, nil
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}
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// appendResultsToDNSResponse builds dns message from the discovery results and
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// appends them to the dns response.
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func (d messageSerializer) appendResultsToDNSResponse(opts *serializeOptions) {
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// Always add the SOA record if requested.
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if opts.req.Question[0].Qtype == dns.TypeSOA {
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opts.resp.Answer = append(opts.resp.Answer, opts.dnsRecordMaker.makeSOA(opts.responseDomain, opts.cfg))
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}
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handled := make(map[string]struct{})
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var answerCNAME []dns.RR = nil
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count := 0
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for _, result := range opts.results {
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for _, port := range getPortsFromResult(result) {
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// Add the node record
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had_answer := false
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ans, extra, _ := d.getAnswerExtraAndNs(serializeToGetAnswerExtraAndNsOptions(opts, result, port))
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opts.resp.Extra = append(opts.resp.Extra, extra...)
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if len(ans) == 0 {
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continue
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}
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// Avoid duplicate entries, possible if a node has
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// the same service on multiple ports, etc.
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if _, ok := handled[ans[0].String()]; ok {
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continue
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}
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handled[ans[0].String()] = struct{}{}
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switch ans[0].(type) {
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case *dns.CNAME:
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// keep track of the first CNAME + associated RRs but don't add to the resp.Answer yet
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// this will only be added if no non-CNAME RRs are found
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if len(answerCNAME) == 0 {
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answerCNAME = ans
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}
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default:
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opts.resp.Answer = append(opts.resp.Answer, ans...)
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had_answer = true
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}
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if had_answer {
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count++
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if count == opts.cfg.ARecordLimit {
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// We stop only if greater than 0 or we reached the limit
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return
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}
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}
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}
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}
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if len(opts.resp.Answer) == 0 && len(answerCNAME) > 0 {
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opts.resp.Answer = answerCNAME
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}
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}
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// getAnswerExtraAndNsOptions are the options for getting the Answer, Extra, and Ns records for a DNS response.
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type getAnswerExtraAndNsOptions struct {
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port discovery.Port
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result *discovery.Result
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req *dns.Msg
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reqCtx Context
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query *discovery.Query
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results []*discovery.Result
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resp *dns.Msg
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cfg *RouterDynamicConfig
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responseDomain string
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remoteAddress net.Addr
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maxRecursionLevel int
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ttl uint32
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dnsRecordMaker dnsRecordMaker
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translateAddressFunc func(dc string, addr string, taggedAddresses map[string]string, accept dnsutil.TranslateAddressAccept) string
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translateServiceAddressFunc func(dc string, address string, taggedAddresses map[string]structs.ServiceAddress, accept dnsutil.TranslateAddressAccept) string
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resolveCnameFunc func(cfgContext *RouterDynamicConfig, name string, reqCtx Context, remoteAddress net.Addr, maxRecursionLevel int) []dns.RR
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}
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// getAnswerAndExtra creates the dns answer and extra from discovery results.
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func (d messageSerializer) getAnswerExtraAndNs(opts *getAnswerExtraAndNsOptions) (answer []dns.RR, extra []dns.RR, ns []dns.RR) {
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serviceAddress, nodeAddress := d.getServiceAndNodeAddresses(opts)
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qName := opts.req.Question[0].Name
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ttlLookupName := qName
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if opts.query != nil {
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ttlLookupName = opts.query.QueryPayload.Name
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}
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opts.ttl = getTTLForResult(ttlLookupName, opts.result.DNS.TTL, opts.query, opts.cfg)
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qType := opts.req.Question[0].Qtype
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// TODO (v2-dns): skip records that refer to a workload/node that don't have a valid DNS name.
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// Special case responses
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switch {
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// PTR requests are first since they are a special case of domain overriding question type
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case parseRequestType(opts.req) == requestTypeIP:
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ptrTarget := ""
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if opts.result.Type == discovery.ResultTypeNode {
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ptrTarget = opts.result.Node.Name
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} else if opts.result.Type == discovery.ResultTypeService {
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ptrTarget = opts.result.Service.Name
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}
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ptr := &dns.PTR{
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Hdr: dns.RR_Header{Name: qName, Rrtype: dns.TypePTR, Class: dns.ClassINET, Ttl: 0},
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Ptr: canonicalNameForResult(opts.result.Type, ptrTarget, opts.responseDomain, opts.result.Tenancy, opts.port.Name),
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}
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answer = append(answer, ptr)
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case qType == dns.TypeNS:
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resultType := opts.result.Type
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target := opts.result.Node.Name
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if parseRequestType(opts.req) == requestTypeConsul && resultType == discovery.ResultTypeService {
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resultType = discovery.ResultTypeNode
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}
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fqdn := canonicalNameForResult(resultType, target, opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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extraRecord := opts.dnsRecordMaker.makeIPBasedRecord(fqdn, nodeAddress, opts.ttl)
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answer = append(answer, opts.dnsRecordMaker.makeNS(opts.responseDomain, fqdn, opts.ttl))
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extra = append(extra, extraRecord)
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case qType == dns.TypeSOA:
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// to be returned in the result.
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fqdn := canonicalNameForResult(opts.result.Type, opts.result.Node.Name, opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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extraRecord := opts.dnsRecordMaker.makeIPBasedRecord(fqdn, nodeAddress, opts.ttl)
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ns = append(ns, opts.dnsRecordMaker.makeNS(opts.responseDomain, fqdn, opts.ttl))
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extra = append(extra, extraRecord)
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case qType == dns.TypeSRV:
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fallthrough
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default:
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a, e := d.getAnswerExtrasForAddressAndTarget(nodeAddress, serviceAddress, opts)
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answer = append(answer, a...)
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extra = append(extra, e...)
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}
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a, e := getAnswerAndExtraTXT(opts.req, opts.cfg, qName, opts.result, opts.ttl,
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opts.responseDomain, opts.query, &opts.port, opts.dnsRecordMaker)
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answer = append(answer, a...)
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extra = append(extra, e...)
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return
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}
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// getServiceAndNodeAddresses returns the service and node addresses from a discovery result.
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func (d messageSerializer) getServiceAndNodeAddresses(opts *getAnswerExtraAndNsOptions) (*dnsAddress, *dnsAddress) {
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addrTranslate := dnsutil.TranslateAddressAcceptDomain
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if opts.req.Question[0].Qtype == dns.TypeA {
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addrTranslate |= dnsutil.TranslateAddressAcceptIPv4
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} else if opts.req.Question[0].Qtype == dns.TypeAAAA {
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addrTranslate |= dnsutil.TranslateAddressAcceptIPv6
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} else {
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addrTranslate |= dnsutil.TranslateAddressAcceptAny
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}
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// The datacenter should be empty during translation if it is a peering lookup.
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// This should be fine because we should always prefer the WAN address.
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serviceAddress := newDNSAddress("")
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if opts.result.Service != nil {
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sa := opts.translateServiceAddressFunc(opts.result.Tenancy.Datacenter,
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opts.result.Service.Address, getServiceAddressMapFromLocationMap(opts.result.Service.TaggedAddresses),
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addrTranslate)
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serviceAddress = newDNSAddress(sa)
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}
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nodeAddress := newDNSAddress("")
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if opts.result.Node != nil {
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na := opts.translateAddressFunc(opts.result.Tenancy.Datacenter, opts.result.Node.Address,
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getStringAddressMapFromTaggedAddressMap(opts.result.Node.TaggedAddresses), addrTranslate)
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nodeAddress = newDNSAddress(na)
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}
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return serviceAddress, nodeAddress
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}
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// getAnswerExtrasForAddressAndTarget creates the dns answer and extra from nodeAddress and serviceAddress dnsAddress pairs.
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func (d messageSerializer) getAnswerExtrasForAddressAndTarget(nodeAddress *dnsAddress,
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serviceAddress *dnsAddress, opts *getAnswerExtraAndNsOptions) (answer []dns.RR, extra []dns.RR) {
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qName := opts.req.Question[0].Name
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reqType := parseRequestType(opts.req)
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switch {
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case (reqType == requestTypeAddress || opts.result.Type == discovery.ResultTypeVirtual) &&
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serviceAddress.IsEmptyString() && nodeAddress.IsIP():
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a, e := getAnswerExtrasForIP(qName, nodeAddress, opts.req.Question[0], reqType, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, false)
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answer = append(answer, a...)
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extra = append(extra, e...)
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case opts.result.Type == discovery.ResultTypeNode && nodeAddress.IsIP():
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canonicalNodeName := canonicalNameForResult(opts.result.Type,
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opts.result.Node.Name, opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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a, e := getAnswerExtrasForIP(canonicalNodeName, nodeAddress, opts.req.Question[0], reqType, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, false)
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answer = append(answer, a...)
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extra = append(extra, e...)
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case opts.result.Type == discovery.ResultTypeNode && !nodeAddress.IsIP():
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a, e := d.makeRecordFromFQDN(serviceAddress.FQDN(), opts)
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answer = append(answer, a...)
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extra = append(extra, e...)
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case serviceAddress.IsEmptyString() && nodeAddress.IsEmptyString():
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return nil, nil
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// There is no service address and the node address is an IP
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case serviceAddress.IsEmptyString() && nodeAddress.IsIP():
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resultType := discovery.ResultTypeNode
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if opts.result.Type == discovery.ResultTypeWorkload {
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resultType = discovery.ResultTypeWorkload
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}
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canonicalNodeName := canonicalNameForResult(resultType, opts.result.Node.Name,
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opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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a, e := getAnswerExtrasForIP(canonicalNodeName, nodeAddress, opts.req.Question[0], reqType, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, nodeAddress.String() == opts.result.Node.Address) // We compare the node address to the result to detect changes from the WAN translation
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answer = append(answer, a...)
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extra = append(extra, e...)
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// There is no service address and the node address is a FQDN (external service)
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case serviceAddress.IsEmptyString():
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a, e := d.makeRecordFromFQDN(nodeAddress.FQDN(), opts)
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answer = append(answer, a...)
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extra = append(extra, e...)
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case serviceAddress.IsIP() && opts.req.Question[0].Qtype == dns.TypeSRV:
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a, e := getAnswerExtrasForIP(qName, serviceAddress, opts.req.Question[0], requestTypeName, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, false)
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answer = append(answer, a...)
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extra = append(extra, e...)
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// The service address is an IP
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case serviceAddress.IsIP():
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canonicalServiceName := canonicalNameForResult(discovery.ResultTypeService,
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opts.result.Service.Name, opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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a, e := getAnswerExtrasForIP(canonicalServiceName, serviceAddress, opts.req.Question[0], reqType, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, false)
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answer = append(answer, a...)
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extra = append(extra, e...)
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// If the service address is a CNAME for the service we are looking
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// for then use the node address.
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case serviceAddress.FQDN() == opts.req.Question[0].Name && nodeAddress.IsIP():
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canonicalNodeName := canonicalNameForResult(discovery.ResultTypeNode,
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opts.result.Node.Name, opts.responseDomain, opts.result.Tenancy, opts.port.Name)
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a, e := getAnswerExtrasForIP(canonicalNodeName, nodeAddress, opts.req.Question[0], reqType, opts.result, opts.ttl, opts.responseDomain, &opts.port, opts.dnsRecordMaker, nodeAddress.String() == opts.result.Node.Address) // We compare the node address to the result to detect changes from the WAN translation
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answer = append(answer, a...)
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extra = append(extra, e...)
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// The service address is a FQDN (internal or external service name)
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default:
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a, e := d.makeRecordFromFQDN(serviceAddress.FQDN(), opts)
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answer = append(answer, a...)
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extra = append(extra, e...)
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}
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return
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}
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// makeRecordFromFQDN creates a DNS record from a FQDN.
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func (d messageSerializer) makeRecordFromFQDN(fqdn string, opts *getAnswerExtraAndNsOptions) ([]dns.RR, []dns.RR) {
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edns := opts.req.IsEdns0() != nil
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q := opts.req.Question[0]
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more := opts.resolveCnameFunc(opts.cfg, dns.Fqdn(fqdn), opts.reqCtx, opts.remoteAddress, opts.maxRecursionLevel)
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var additional []dns.RR
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extra := 0
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MORE_REC:
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for _, rr := range more {
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switch rr.Header().Rrtype {
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case dns.TypeCNAME, dns.TypeA, dns.TypeAAAA, dns.TypeTXT:
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// set the TTL manually
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rr.Header().Ttl = opts.ttl
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additional = append(additional, rr)
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extra++
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if extra == maxRecurseRecords && !edns {
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break MORE_REC
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}
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}
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}
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if q.Qtype == dns.TypeSRV {
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answer := opts.dnsRecordMaker.makeSRV(q.Name, fqdn, uint16(opts.result.DNS.Weight), opts.ttl, &opts.port)
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return []dns.RR{answer}, additional
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}
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address := ""
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if opts.result.Service != nil && opts.result.Service.Address != "" {
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address = opts.result.Service.Address
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} else if opts.result.Node != nil {
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address = opts.result.Node.Address
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}
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answers := []dns.RR{
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opts.dnsRecordMaker.makeCNAME(q.Name, address, opts.ttl),
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}
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answers = append(answers, additional...)
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return answers, nil
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}
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// getAnswerAndExtraTXT determines whether a TXT needs to be create and then
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// returns the TXT record in the answer or extra depending on the question type.
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func getAnswerAndExtraTXT(req *dns.Msg, cfg *RouterDynamicConfig, qName string,
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result *discovery.Result, ttl uint32, domain string, query *discovery.Query,
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port *discovery.Port, maker dnsRecordMaker) (answer []dns.RR, extra []dns.RR) {
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if !shouldAppendTXTRecord(query, cfg, req) {
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return
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}
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recordHeaderName := qName
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serviceAddress := newDNSAddress("")
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if result.Service != nil {
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serviceAddress = newDNSAddress(result.Service.Address)
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}
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if result.Type != discovery.ResultTypeNode &&
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result.Type != discovery.ResultTypeVirtual &&
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!serviceAddress.IsInternalFQDN(domain) &&
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!serviceAddress.IsExternalFQDN(domain) {
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recordHeaderName = canonicalNameForResult(discovery.ResultTypeNode, result.Node.Name,
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domain, result.Tenancy, port.Name)
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}
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qType := req.Question[0].Qtype
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generateMeta := false
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metaInAnswer := false
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if qType == dns.TypeANY || qType == dns.TypeTXT {
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generateMeta = true
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metaInAnswer = true
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} else if cfg.NodeMetaTXT {
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generateMeta = true
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}
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// Do not generate txt records if we don't have to: https://github.com/hashicorp/consul/pull/5272
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if generateMeta {
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meta := maker.makeTXT(recordHeaderName, result.Metadata, ttl)
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if metaInAnswer {
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answer = append(answer, meta...)
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} else {
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extra = append(extra, meta...)
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}
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}
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return answer, extra
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}
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// shouldAppendTXTRecord determines whether a TXT record should be appended to the response.
|
|
func shouldAppendTXTRecord(query *discovery.Query, cfg *RouterDynamicConfig, req *dns.Msg) bool {
|
|
qType := req.Question[0].Qtype
|
|
switch {
|
|
// Node records
|
|
case query != nil && query.QueryType == discovery.QueryTypeNode && (cfg.NodeMetaTXT || qType == dns.TypeANY || qType == dns.TypeTXT):
|
|
return true
|
|
// Service records
|
|
case query != nil && query.QueryType == discovery.QueryTypeService && cfg.NodeMetaTXT && qType == dns.TypeSRV:
|
|
return true
|
|
// Prepared query records
|
|
case query != nil && query.QueryType == discovery.QueryTypePreparedQuery && cfg.NodeMetaTXT && qType == dns.TypeSRV:
|
|
return true
|
|
}
|
|
return false
|
|
}
|
|
|
|
// getAnswerExtrasForIP creates the dns answer and extra from IP dnsAddress pairs.
|
|
func getAnswerExtrasForIP(name string, addr *dnsAddress, question dns.Question, reqType requestType, result *discovery.Result, ttl uint32, domain string, port *discovery.Port, maker dnsRecordMaker, addressOverridden bool) (answer []dns.RR, extra []dns.RR) {
|
|
qType := question.Qtype
|
|
canReturnARecord := qType == dns.TypeSRV || qType == dns.TypeA || qType == dns.TypeANY || qType == dns.TypeNS || qType == dns.TypeTXT
|
|
canReturnAAAARecord := qType == dns.TypeSRV || qType == dns.TypeAAAA || qType == dns.TypeANY || qType == dns.TypeNS || qType == dns.TypeTXT
|
|
if reqType != requestTypeAddress && result.Type != discovery.ResultTypeVirtual {
|
|
switch {
|
|
// check IPV4
|
|
case addr.IsIP() && addr.IsIPV4() && !canReturnARecord,
|
|
// check IPV6
|
|
addr.IsIP() && !addr.IsIPV4() && !canReturnAAAARecord:
|
|
return
|
|
}
|
|
}
|
|
|
|
// Have to pass original question name here even if the system has recursed
|
|
// and stripped off the domain suffix.
|
|
recHdrName := question.Name
|
|
if qType == dns.TypeSRV {
|
|
nameSplit := strings.Split(name, ".")
|
|
if len(nameSplit) > 1 && nameSplit[1] == addrLabel {
|
|
recHdrName = name
|
|
} else {
|
|
recHdrName = name
|
|
}
|
|
name = question.Name
|
|
}
|
|
|
|
if reqType != requestTypeAddress && qType == dns.TypeSRV {
|
|
|
|
if addr.IsIP() && question.Name == name && !addressOverridden {
|
|
// encode the ip to be used in the header of the A/AAAA record
|
|
// as well as the target of the SRV record.
|
|
recHdrName = encodeIPAsFqdn(result, addr.IP(), domain)
|
|
}
|
|
if result.Type == discovery.ResultTypeWorkload {
|
|
recHdrName = canonicalNameForResult(result.Type, result.Node.Name, domain, result.Tenancy, port.Name)
|
|
}
|
|
srv := maker.makeSRV(name, recHdrName, uint16(result.DNS.Weight), ttl, port)
|
|
answer = append(answer, srv)
|
|
}
|
|
|
|
record := maker.makeIPBasedRecord(recHdrName, addr, ttl)
|
|
|
|
isARecordWhenNotExplicitlyQueried := record.Header().Rrtype == dns.TypeA && qType != dns.TypeA && qType != dns.TypeANY
|
|
isAAAARecordWhenNotExplicitlyQueried := record.Header().Rrtype == dns.TypeAAAA && qType != dns.TypeAAAA && qType != dns.TypeANY
|
|
|
|
// For explicit A/AAAA queries, we must only return those records in the answer section.
|
|
if isARecordWhenNotExplicitlyQueried ||
|
|
isAAAARecordWhenNotExplicitlyQueried {
|
|
extra = append(extra, record)
|
|
} else {
|
|
answer = append(answer, record)
|
|
}
|
|
|
|
return
|
|
}
|
|
|
|
// getPortsFromResult returns the ports from a discovery result.
|
|
func getPortsFromResult(result *discovery.Result) []discovery.Port {
|
|
if len(result.Ports) > 0 {
|
|
return result.Ports
|
|
}
|
|
// return one record.
|
|
return []discovery.Port{{}}
|
|
}
|
|
|
|
// encodeIPAsFqdn encodes an IP address as a FQDN.
|
|
func encodeIPAsFqdn(result *discovery.Result, ip net.IP, responseDomain string) string {
|
|
ipv4 := ip.To4()
|
|
ipStr := hex.EncodeToString(ip)
|
|
if ipv4 != nil {
|
|
ipStr = ipStr[len(ipStr)-(net.IPv4len*2):]
|
|
}
|
|
if result.Tenancy.PeerName != "" {
|
|
// Exclude the datacenter from the FQDN on the addr for peers.
|
|
// This technically makes no difference, since the addr endpoint ignores the DC
|
|
// component of the request, but do it anyway for a less confusing experience.
|
|
return fmt.Sprintf("%s.addr.%s", ipStr, responseDomain)
|
|
}
|
|
return fmt.Sprintf("%s.addr.%s.%s", ipStr, result.Tenancy.Datacenter, responseDomain)
|
|
}
|
|
|
|
// canonicalNameForResult returns the canonical name for a discovery result.
|
|
func canonicalNameForResult(resultType discovery.ResultType, target, domain string,
|
|
tenancy discovery.ResultTenancy, portName string) string {
|
|
switch resultType {
|
|
case discovery.ResultTypeService:
|
|
if tenancy.Namespace != "" {
|
|
return fmt.Sprintf("%s.%s.%s.%s.%s", target, "service", tenancy.Namespace, tenancy.Datacenter, domain)
|
|
}
|
|
return fmt.Sprintf("%s.%s.%s.%s", target, "service", tenancy.Datacenter, domain)
|
|
case discovery.ResultTypeNode:
|
|
if tenancy.PeerName != "" && tenancy.Partition != "" {
|
|
// We must return a more-specific DNS name for peering so
|
|
// that there is no ambiguity with lookups.
|
|
// Nodes are always registered in the default namespace, so
|
|
// the `.ns` qualifier is not required.
|
|
return fmt.Sprintf("%s.node.%s.peer.%s.ap.%s",
|
|
target,
|
|
tenancy.PeerName,
|
|
tenancy.Partition,
|
|
domain)
|
|
}
|
|
if tenancy.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",
|
|
target,
|
|
tenancy.PeerName,
|
|
domain)
|
|
}
|
|
// Return a simpler format for non-peering nodes.
|
|
return fmt.Sprintf("%s.node.%s.%s", target, tenancy.Datacenter, domain)
|
|
case discovery.ResultTypeWorkload:
|
|
// TODO (v2-dns): it doesn't appear this is being used to return a result. Need to investigate and refactor
|
|
if portName != "" {
|
|
return fmt.Sprintf("%s.port.%s.workload.%s.ns.%s.ap.%s", portName, target, tenancy.Namespace, tenancy.Partition, domain)
|
|
}
|
|
return fmt.Sprintf("%s.workload.%s.ns.%s.ap.%s", target, tenancy.Namespace, tenancy.Partition, domain)
|
|
}
|
|
return ""
|
|
}
|
|
|
|
// getServiceAddressMapFromLocationMap converts a map of Location to a map of ServiceAddress.
|
|
func getServiceAddressMapFromLocationMap(taggedAddresses map[string]*discovery.TaggedAddress) map[string]structs.ServiceAddress {
|
|
taggedServiceAddresses := make(map[string]structs.ServiceAddress, len(taggedAddresses))
|
|
for k, v := range taggedAddresses {
|
|
taggedServiceAddresses[k] = structs.ServiceAddress{
|
|
Address: v.Address,
|
|
Port: int(v.Port.Number),
|
|
}
|
|
}
|
|
return taggedServiceAddresses
|
|
}
|
|
|
|
// getStringAddressMapFromTaggedAddressMap converts a map of Location to a map of string.
|
|
func getStringAddressMapFromTaggedAddressMap(taggedAddresses map[string]*discovery.TaggedAddress) map[string]string {
|
|
taggedServiceAddresses := make(map[string]string, len(taggedAddresses))
|
|
for k, v := range taggedAddresses {
|
|
taggedServiceAddresses[k] = v.Address
|
|
}
|
|
return taggedServiceAddresses
|
|
}
|
|
|
|
// getTTLForResult returns the TTL for a given result.
|
|
func getTTLForResult(name string, overrideTTL *uint32, query *discovery.Query, cfg *RouterDynamicConfig) uint32 {
|
|
// In the case we are not making a discovery query, such as addr. or arpa. lookups,
|
|
// use the node TTL by convention
|
|
if query == nil {
|
|
return uint32(cfg.NodeTTL / time.Second)
|
|
}
|
|
|
|
if overrideTTL != nil {
|
|
// If a result was provided with an override, use that. This is the case for some prepared queries.
|
|
return *overrideTTL
|
|
}
|
|
|
|
switch query.QueryType {
|
|
case discovery.QueryTypeService, discovery.QueryTypePreparedQuery:
|
|
ttl, ok := cfg.GetTTLForService(name)
|
|
if ok {
|
|
return uint32(ttl / time.Second)
|
|
}
|
|
fallthrough
|
|
default:
|
|
return uint32(cfg.NodeTTL / time.Second)
|
|
}
|
|
}
|
|
|
|
// serializeToGetAnswerExtraAndNsOptions converts serializeOptions to getAnswerExtraAndNsOptions.
|
|
func serializeToGetAnswerExtraAndNsOptions(opts *serializeOptions,
|
|
result *discovery.Result, port discovery.Port) *getAnswerExtraAndNsOptions {
|
|
return &getAnswerExtraAndNsOptions{
|
|
port: port,
|
|
result: result,
|
|
req: opts.req,
|
|
reqCtx: opts.reqCtx,
|
|
query: opts.query,
|
|
results: opts.results,
|
|
resp: opts.resp,
|
|
cfg: opts.cfg,
|
|
responseDomain: opts.responseDomain,
|
|
remoteAddress: opts.remoteAddress,
|
|
maxRecursionLevel: opts.maxRecursionLevel,
|
|
translateAddressFunc: opts.translateAddressFunc,
|
|
translateServiceAddressFunc: opts.translateServiceAddressFunc,
|
|
resolveCnameFunc: opts.resolveCnameFunc,
|
|
dnsRecordMaker: opts.dnsRecordMaker,
|
|
}
|
|
}
|