all resolution and tier 1 cname support

handler.go

@@ -3,6 +3,7 @@ package pancheri
 import (
 	"github.com/miekg/dns"
 	"github.com/sirupsen/logrus"
+	"strings"
 )
 
 type Handler struct {
@@ -28,20 +29,274 @@ func (h *Handler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {
 		return
 	}
 
-	question := r.Question[0]
+	q := r.Question[0]
 
-	// okay, do we have upstream resolution enabled?
+	// is it ours?
+	for authority, zone := range h.A.Zones {
+		if strings.HasSuffix(q.Name, authority) {
+			// ok, its an owned domain - respond to it
+			logrus.WithFields(logrus.Fields{
+				"name":  q.Name,
+				"qtype": q.Qtype,
+				"zone":  zone.Zonefile,
+				"raw":   q.String(),
+			}).Trace("responding to query for authoritative zone")
+
+			if q.Qtype == dns.TypeA {
+				record, ok := zone.ARecords[q.Name]
+				if !ok {
+					// SPECIAL CASE: for A and AAAA records, return with a CNAME if and only if that cname exists
+					cname, cok := zone.CNAMERecords[q.Name]
+					if cok {
+						// return with the CNAME record instead and resolve the CNAME
+						rendered := cname.Render()
+						msg.Rcode = dns.RcodeSuccess
+						msg.Answer = []dns.RR{
+							rendered,
+						}
+						msg.RecursionAvailable = true
+						msg.Authoritative = true
+
+						for authority, zone := range h.A.Zones {
+							if strings.HasSuffix(cname.Target, authority) {
+								// its authoritative
+								if rec, ok := zone.CNAMERecords[cname.Target]; ok {
+									// double cname isn't allowed right now
+									logrus.WithFields(logrus.Fields{
+										"in":      q.Name,
+										"target":  cname.Target,
+										"target2": rec.Target,
+									}).Error("double cname")
+									msg.Answer = []dns.RR{}
+									msg.Rcode = dns.RcodeNameError
+									break
+								}
+								if rec, ok := zone.ARecords[cname.Target]; ok {
+									msg.Answer = append(msg.Answer, rec.Render())
+								}
+							}
+						}
+						if len(msg.Answer) == 1 && msg.Rcode == dns.RcodeSuccess {
+							// ok, it's not ours
+							// this is also not allowed right now (TODO)
+							logrus.WithFields(logrus.Fields{
+								"in":     q.Name,
+								"target": cname.Target,
+							}).Error("external cname (TODO)")
+							msg.Answer = []dns.RR{}
+							msg.Rcode = dns.RcodeNameError
+							break
+						}
+
+						err := w.WriteMsg(msg)
+						if err != nil {
+							logrus.Errorf("error responding: %s", err)
+							return
+						}
+						return
+					} else {
+						// send an nxdomain
+						if r.RecursionDesired {
+							msg.RecursionAvailable = true
+						}
+						msg.Rcode = dns.RcodeNameError
+						err := w.WriteMsg(msg)
+						if err != nil {
+							logrus.Errorf("error responding: %s", err)
+							return
+						}
+						return
+					}
+				}
+				// return with the record
+				rendered := record.Render()
+				msg.Rcode = dns.RcodeSuccess
+				msg.Answer = []dns.RR{
+					rendered,
+				}
+				msg.RecursionAvailable = true
+				msg.Authoritative = true
+				err := w.WriteMsg(msg)
+				if err != nil {
+					logrus.Errorf("error responding: %s", err)
+					return
+				}
+				return
+			} else if q.Qtype == dns.TypeAAAA {
+				record, ok := zone.AAAARecords[q.Name]
+				if !ok {
+					// SPECIAL CASE: for A and AAAA records, return with a CNAME if and only if that cname exists
+					cname, cok := zone.CNAMERecords[q.Name]
+					if cok {
+						// return with the CNAME record instead and resolve the CNAME
+						rendered := cname.Render()
+						msg.Rcode = dns.RcodeSuccess
+						msg.Answer = []dns.RR{
+							rendered,
+						}
+						msg.RecursionAvailable = true
+						msg.Authoritative = true
+
+						for authority, zone := range h.A.Zones {
+							if strings.HasSuffix(cname.Target, authority) {
+								// its authoritative
+								if rec, ok := zone.CNAMERecords[cname.Target]; ok {
+									// double cname isn't allowed right now
+									logrus.WithFields(logrus.Fields{
+										"in":      q.Name,
+										"target":  cname.Target,
+										"target2": rec.Target,
+									}).Error("double cname")
+									msg.Answer = []dns.RR{}
+									msg.Rcode = dns.RcodeNameError
+									break
+								}
+								if rec, ok := zone.AAAARecords[cname.Target]; ok {
+									msg.Answer = append(msg.Answer, rec.Render())
+								}
+							}
+						}
+						if len(msg.Answer) == 1 && msg.Rcode == dns.RcodeSuccess {
+							// ok, it's not ours
+							// this is also not allowed right now (TODO)
+							logrus.WithFields(logrus.Fields{
+								"in":     q.Name,
+								"target": cname.Target,
+							}).Error("external cname (TODO)")
+							msg.Answer = []dns.RR{}
+							msg.Rcode = dns.RcodeNameError
+							break
+						}
+
+						err := w.WriteMsg(msg)
+						if err != nil {
+							logrus.Errorf("error responding: %s", err)
+							return
+						}
+						return
+					} else {
+						// send an nxdomain
+						if r.RecursionDesired {
+							msg.RecursionAvailable = true
+						}
+						msg.Rcode = dns.RcodeNameError
+						err := w.WriteMsg(msg)
+						if err != nil {
+							logrus.Errorf("error responding: %s", err)
+							return
+						}
+						return
+					}
+				}
+				// return with the record
+				rendered := record.Render()
+				msg.Rcode = dns.RcodeSuccess
+				msg.Answer = []dns.RR{
+					rendered,
+				}
+				msg.RecursionAvailable = true
+				msg.Authoritative = true
+				err := w.WriteMsg(msg)
+				logrus.Trace(msg.String())
+				if err != nil {
+					logrus.Errorf("error responding: %s", err)
+					return
+				}
+				return
+			} else if q.Qtype == dns.TypeCNAME {
+				record, ok := zone.CNAMERecords[q.Name]
+				if !ok {
+					// send an nxdomain
+					if r.RecursionDesired {
+						msg.RecursionAvailable = true
+					}
+					msg.Rcode = dns.RcodeNameError
+					err := w.WriteMsg(msg)
+					if err != nil {
+						logrus.Errorf("error responding: %s", err)
+						return
+					}
+					return
+				}
+				// return with the record
+				rendered := record.Render()
+				msg.Rcode = dns.RcodeSuccess
+				msg.Answer = []dns.RR{
+					rendered,
+				}
+				msg.RecursionAvailable = true
+				msg.Authoritative = true
+				err := w.WriteMsg(msg)
+				logrus.Trace(msg.String())
+				if err != nil {
+					logrus.Errorf("error responding: %s", err)
+					return
+				}
+				return
+			} else if q.Qtype == dns.TypeTXT {
+				record, ok := zone.TXTRecords[q.Name]
+				if !ok {
+					// send an nxdomain
+					if r.RecursionDesired {
+						msg.RecursionAvailable = true
+					}
+					msg.Rcode = dns.RcodeNameError
+					err := w.WriteMsg(msg)
+					if err != nil {
+						logrus.Errorf("error responding: %s", err)
+						return
+					}
+					return
+				}
+				// return with the record
+				rendered := record.Render()
+				msg.Rcode = dns.RcodeSuccess
+				msg.Answer = []dns.RR{
+					rendered,
+				}
+				msg.RecursionAvailable = true
+				msg.Authoritative = true
+				err := w.WriteMsg(msg)
+				logrus.Trace(msg.String())
+				if err != nil {
+					logrus.Errorf("error responding: %s", err)
+					return
+				}
+				return
+			} else {
+				// not supported
+				logrus.WithFields(logrus.Fields{
+					"name":  q.Name,
+					"qtype": q.Qtype,
+				}).Error("received unsupported question type")
+				// send an nxdomain
+				if r.RecursionDesired {
+					msg.RecursionAvailable = true
+				}
+				msg.Rcode = dns.RcodeNameError
+				err := w.WriteMsg(msg)
+				if err != nil {
+					logrus.Errorf("error responding: %s", err)
+					return
+				}
+				return
+			}
+
+			return
+		}
+	}
+	// no. do we have upstream resolution enabled?
 	if h.C.Resolver.Enable {
 		// alright, resolve it with the resolver
-		answers, rcode, err := h.R.Resolve(question.Name, question.Qtype)
+		resp, err := h.R.Resolve(q.Name, q.Qtype)
+		resp.SetReply(r)
+
 		if err != nil {
 			logrus.Errorf("error resolving: %s", err)
 			return
 		}
-		msg.Rcode = rcode
-		msg.Answer = append(msg.Answer, answers...)
 
-		err = w.WriteMsg(msg)
+		err = w.WriteMsg(resp)
 		if err != nil {
 			logrus.Errorf("error responding: %s", err)
 			return

resolver.go

@@ -17,7 +17,7 @@ func NewResolver(upstream string) *Resolver {
 	}
 }
 
-func (r *Resolver) Resolve(domain string, qtype uint16) ([]dns.RR, int, error) {
+func (r *Resolver) Resolve(domain string, qtype uint16) (*dns.Msg, error) {
 	logrus.WithFields(logrus.Fields{
 		"domain": domain,
 		"qtype":  qtype,
@@ -33,5 +33,5 @@ func (r *Resolver) Resolve(domain string, qtype uint16) ([]dns.RR, int, error) {
 		return nil, err
 	}
 
-	return in.Answer, in.Rcode, nil
+	return in, nil
 }

zone.go

@@ -6,23 +6,20 @@ import (
 )
 
 type Zone struct {
-	Root         string        `yaml:"root"`
-	ReducedHash  string        `yaml:"rsha"`
-	Zonefile     string        `yaml:"zf"`
-	ARecords     []RecordA     `yaml:"ra"`
-	AAAARecords  []RecordAAAA  `yaml:"rav6"`
-	CNAMERecords []RecordCNAME `yaml:"rcn"`
-	TXTRecords   []RecordTXT   `yaml:"rtx"`
+	Root         string                 `yaml:"root"`
+	ReducedHash  string                 `yaml:"rsha"`
+	Zonefile     string                 `yaml:"zf"`
+	ARecords     map[string]RecordA     `yaml:"ra"`
+	AAAARecords  map[string]RecordAAAA  `yaml:"rav6"`
+	CNAMERecords map[string]RecordCNAME `yaml:"rcn"`
+	TXTRecords   map[string]RecordTXT   `yaml:"rtx"`
 }
 
 func (z *Zone) RenderZone() string {
 	outString := ""
 	outString += fmt.Sprintf(";; Rendered zonefile for %s (rsha %s) at %s\n", z.Zonefile, z.ReducedHash, time.Now().Format(time.RFC3339))
 	outString += ";; Generated by pancheri-render. Note: this will NOT work out of the box!\n"
-	outString += ";; At the very least, you'll need to change the SOA and NS values.\n"
-	outString += "\n"
-	outString += ";; SOA & NS records\n"
-	outString += ";; TODO\n"
+	outString += ";; At the very least, you'll need add SOA and NS values.\n"
 	outString += "\n"
 	outString += ";; A Records\n"
 

zone_config.go

@@ -61,10 +61,10 @@ func LoadZone(path string) (*Zone, error) {
 		Root:         cfg.Zone.Root,
 		ReducedHash:  reducedHash,
 		Zonefile:     path,
-		ARecords:     nil,
-		AAAARecords:  nil,
-		CNAMERecords: nil,
-		TXTRecords:   nil,
+		ARecords:     make(map[string]RecordA),
+		AAAARecords:  make(map[string]RecordAAAA),
+		CNAMERecords: make(map[string]RecordCNAME),
+		TXTRecords:   make(map[string]RecordTXT),
 	}
 
 	for _, record := range cfg.Zone.Records {
@@ -83,11 +83,14 @@ func LoadZone(path string) (*Zone, error) {
 				if !strings.HasSuffix(domain, ".") {
 					domain = domain + "." + cfg.Zone.Root + "."
 				}
-				zone.ARecords = append(zone.ARecords, RecordA{
+				if _, ok := zone.ARecords[domain]; ok {
+					return nil, errors.New("duplicate A record " + domain)
+				}
+				zone.ARecords[domain] = RecordA{
 					In:  domain,
 					Ip:  record.Ipv4.To4(),
 					TTL: record.TTL,
-				})
+				}
 			}
 		} else if record.RecordType == RuleTypeAAAA {
 			// req.d fields: in, ip, ttl
@@ -104,11 +107,14 @@ func LoadZone(path string) (*Zone, error) {
 				if !strings.HasSuffix(domain, ".") {
 					domain = domain + "." + cfg.Zone.Root + "."
 				}
-				zone.AAAARecords = append(zone.AAAARecords, RecordAAAA{
+				if _, ok := zone.AAAARecords[domain]; ok {
+					return nil, errors.New("duplicate AAAA record " + domain)
+				}
+				zone.AAAARecords[domain] = RecordAAAA{
 					In:  domain,
 					Ip:  record.Ipv6,
 					TTL: record.TTL,
-				})
+				}
 			}
 		} else if record.RecordType == RuleTypeCNAME {
 			// req.d fields: in, ip, ttl
@@ -121,15 +127,21 @@ func LoadZone(path string) (*Zone, error) {
 			if record.TTL == 0 {
 				return nil, errors.New("CNAME record TTL cannot be 0 or empty")
 			}
+			if !strings.HasSuffix(record.Target, ".") {
+				record.Target = record.Target + "." + cfg.Zone.Root + "."
+			}
 			for _, domain := range record.Domains {
 				if !strings.HasSuffix(domain, ".") {
 					domain = domain + "." + cfg.Zone.Root + "."
 				}
-				zone.CNAMERecords = append(zone.CNAMERecords, RecordCNAME{
+				if _, ok := zone.CNAMERecords[domain]; ok {
+					return nil, errors.New("duplicate CNAME record " + domain)
+				}
+				zone.CNAMERecords[domain] = RecordCNAME{
 					In:     domain,
 					Target: record.Target,
 					TTL:    record.TTL,
-				})
+				}
 			}
 		} else if record.RecordType == RuleTypeTXT {
 			// req.d fields: in, content, ttl
@@ -146,11 +158,14 @@ func LoadZone(path string) (*Zone, error) {
 				if !strings.HasSuffix(domain, ".") {
 					domain = domain + "." + cfg.Zone.Root + "."
 				}
-				zone.TXTRecords = append(zone.TXTRecords, RecordTXT{
+				if _, ok := zone.TXTRecords[domain]; ok {
+					return nil, errors.New("duplicate TXT record " + domain)
+				}
+				zone.TXTRecords[domain] = RecordTXT{
 					In:      domain,
 					Content: record.Content,
 					TTL:     record.TTL,
-				})
+				}
 			}
 		}
 	}