Added zone alias support, glue records

dns.go

@@ -12,32 +12,16 @@ import (
 	"time"
 )
 
-type RRSet []dns.RR
-
-func (l RRSet) Get(rrt uint16, name string) (rrset RRSet) {
-	for _, rr := range l {
-		if rr != nil && rr.Header().Rrtype == rrt && rr.Header().Name == name {
-			rrset = append(rrset, rr)
-		}
-	}
-
-	return
-}
-
-func (l RRSet) Delete(rrt uint16, name string) {
-	for i, rr := range l {
-		if rr != nil && rr.Header().Rrtype == rrt && rr.Header().Name == name {
-			l[i] = nil
-		}
-	}
-}
-
 type Zone struct {
 	publicKey  ed25519.PublicKey
 	privateKey ed25519.PrivateKey
 
 	dnsKey *dns.DNSKEY
 
+	baseZone string
+
+	zoneAliases []string
+
 	rrset RRSet
 
 	enforcedEntries RRSet
@@ -61,6 +45,7 @@ func NewZoneFromPublicKey(baseZone string, publicKey ed25519.PublicKey) *Zone {
 
 	zone := &Zone{
 		publicKey: publicKey,
+		baseZone:  baseZone,
 	}
 
 	zone.dnsKey = new(dns.DNSKEY)
@@ -83,7 +68,7 @@ func (z *Zone) DeleteRR(rrtype string, name string) error {
 		return fmt.Errorf("could not find record type for %s", rrtype)
 	}
 
-	z.rrset.Delete(rrt, name)
+	z.rrset.Delete(rrt, z.GetFullName(name))
 	return nil
 }
 
@@ -93,7 +78,11 @@ func (z *Zone) GetRR(rrtype string, name string) (rrset RRSet) {
 		return nil
 	}
 
-	return z.rrset.Get(rrt, name)
+	return z.rrset.Get(rrt, z.GetFullName(name))
+}
+
+func (z *Zone) IsInZone(n string) bool {
+	return strings.HasSuffix(n, z.Name())
 }
 
 func (z *Zone) AddRR(rr dns.RR) error {
@@ -101,7 +90,7 @@ func (z *Zone) AddRR(rr dns.RR) error {
 		return errors.New("no valid record found")
 	}
 
-	if !strings.HasSuffix(rr.Header().Name, z.Name()) {
+	if !z.IsInZone(rr.Header().Name) {
 		return fmt.Errorf("%s is not part of %s", rr.Header().Name, z.Name())
 	}
 
@@ -110,12 +99,24 @@ func (z *Zone) AddRR(rr dns.RR) error {
 	return nil
 }
 
+func (z *Zone) GetFullName(name string) string {
+	if name == "@" || name == "" {
+		//$ORIGIN
+		name = z.Name()
+	} else if !z.IsInZone(name) && name[len(name)-1] != '.' {
+		//Lone names
+		name = name + "." + z.Name()
+	}
+	return name
+}
+
 func (z *Zone) AddRecord(name string, ttl uint32, rr dns.RR) error {
 	if rr == nil {
 		return errors.New("no valid record found")
 	}
+
 	hdr := rr.Header()
-	hdr.Name = name
+	hdr.Name = z.GetFullName(name)
 	hdr.Class = dns.ClassINET
 	hdr.Ttl = ttl
 
@@ -153,6 +154,26 @@ func (z *Zone) AddRecordCNAME(name string, target string, ttl uint32) error {
 	return z.AddRecord(name, ttl, record)
 }
 
+func (z *Zone) AddRecordNS(name string, ns string, ttl uint32) error {
+	record := new(dns.NS)
+	record.Hdr.Rrtype = dns.TypeNS
+	record.Ns = ns
+	return z.AddRecord(name, ttl, record)
+}
+
+func (z *Zone) AddRecordSOA(name string, ns, mbox string, serial, refresh, retry, expire, minttl, ttl uint32) error {
+	record := new(dns.SOA)
+	record.Hdr.Rrtype = dns.TypeSOA
+	record.Ns = ns
+	record.Mbox = mbox
+	record.Serial = serial
+	record.Refresh = refresh
+	record.Retry = retry
+	record.Expire = expire
+	record.Minttl = minttl
+	return z.AddRecord(name, ttl, record)
+}
+
 func (z *Zone) AddRecordTXT(name string, txt []string, ttl uint32) error {
 	record := new(dns.TXT)
 	record.Hdr.Rrtype = dns.TypeTXT
@@ -221,7 +242,7 @@ func (z *Zone) SetRR(rrtype string, name string, rrset RRSet) error {
 		return fmt.Errorf("could not find record type for %s", rrtype)
 	}
 
-	z.rrset.Delete(rrt, name)
+	z.rrset.Delete(rrt, z.GetFullName(name))
 
 	for i, rr := range rrset {
 		if rr != nil && rr.Header().Rrtype != rrt {
@@ -240,15 +261,53 @@ func (z *Zone) SetRR(rrtype string, name string, rrset RRSet) error {
 	return nil
 }
 
-func (z *Zone) GetRRSet() RRSet {
-
-	set := make(RRSet, 0, len(z.rrset))
-	for _, rr := range z.rrset {
-		if rr != nil {
-			set = append(set, rr)
+func (z *Zone) AddZoneAlias(alias string) {
+	for _, a := range z.zoneAliases {
+		if alias == a {
+			return
 		}
 	}
-	return set
+	z.zoneAliases = append(z.zoneAliases, alias)
+}
+
+func (z *Zone) GetRRSet() RRSet {
+	return z.rrset.NotNil()
+}
+
+func (z *Zone) SetEnforcedEntries(set RRSet) {
+	z.enforcedEntries = set
+}
+
+func (z *Zone) GetEnforcedEntries() RRSet {
+	return z.enforcedEntries.NotNil()
+}
+
+func (z *Zone) GetGlueRecords() (result RRSet) {
+
+	//get key records to pin them. Only main Ed25519 KSK is applied
+	result = append(result, z.dnsKey.ToDS(dns.SHA256))
+
+	var nameservers []string
+
+	for _, rr := range z.rrset.Get(dns.TypeNS, z.Name()) {
+		if ns, ok := rr.(*dns.NS); ok {
+			if z.IsInZone(ns.Ns) {
+				nameservers = append(nameservers, ns.Ns)
+			}
+
+			result = append(result, ns)
+		}
+	}
+
+	//get A / AAAA records from nameservers under the zone to glue them
+	func() {
+		for _, ns := range nameservers {
+			result = append(result, z.rrset.Get(dns.TypeA, ns)...)
+			result = append(result, z.rrset.Get(dns.TypeAAAA, ns)...)
+		}
+	}()
+
+	return
 }
 
 func (z *Zone) AddMissingRecords() {
@@ -293,73 +352,93 @@ func (z *Zone) AddMissingRecords() {
 		cds.Hdr.Rrtype = dns.TypeCDS
 		z.AddRR(&cds)
 	}()
+
+	func() {
+		for _, nameset := range z.enforcedEntries.SplitByName() {
+			for _, typeset := range nameset.SplitByType() {
+				z.rrset.Delete(typeset[0].Header().Rrtype, typeset[0].Header().Name)
+				z.rrset = append(z.rrset, typeset...)
+			}
+		}
+	}()
+
+	//clear nil
+	z.rrset = z.rrset.NotNil()
 }
 
-func (z *Zone) Sign() (rrsigs []*dns.RRSIG, err error) {
+var TopLevelCNAMEError = errors.New("top-level CNAME not allowed")
 
-	var types []uint16
-	var names []string
-
-	inTypes := func(i uint16) bool {
-		if i == dns.TypeRRSIG ||
-			i == dns.TypeDS ||
-			i == dns.TypeTA ||
-			i == dns.TypeSOA ||
-			i == dns.TypeRP {
-			return true
-		}
-		for _, j := range types {
-			if i == j {
-				return true
-			}
-		}
-		return false
-	}
-
-	inNames := func(i string) bool {
-		for _, j := range names {
-			if i == j {
-				return true
-			}
-		}
-		return false
-	}
+func (z *Zone) Sign() (zones []*Zone, err error) {
 
+	//SOA
 	z.AddMissingRecords()
+	rrset := z.rrset.RemoveTypes(dns.TypeRRSIG, dns.TypeDS, dns.TypeTA)
 
-	for _, rr := range z.rrset {
-		if rr == nil {
-			continue
-		}
-		h := rr.Header()
-		if !inTypes(h.Rrtype) {
-			types = append(types, h.Rrtype)
-		}
-		if !inNames(h.Name) {
-			names = append(names, h.Name)
-		}
+	//check if a top-level CNAME exists, comply with RFC 1912
+	if len(z.rrset.Get(dns.TypeCNAME, z.Name())) > 0 {
+		return nil, TopLevelCNAMEError
 	}
 
-	//TODO: do check, remove entries
-	/*
-		//TODO: make this an allowlist
-		if rrt == dns.TypeRRSIG ||
-			rrt == dns.TypeDNSKEY ||
-			rrt == dns.TypeCDNSKEY ||
-			rrt == dns.TypeDS ||
-			rrt == dns.TypeCDS ||
-			rrt == dns.TypeNS ||
-			rrt == dns.TypeTA ||
-			rrt == dns.TypeRP ||
-			rrt == dns.TypeSOA { //TODO: allow changing some but with verification of values
-			return fmt.Errorf("type %s not allowed", rrtype)
+	newZone, err := signOneZone(z, rrset)
+	if err != nil {
+		return nil, err
+	}
+	zones = append(zones, newZone)
+
+	for _, alias := range z.zoneAliases {
+
+		aliasZone := *z
+		aliasZone.zoneAliases = nil
+		aliasZone.baseZone = strings.Join(strings.Split(alias, ".")[1:], ".")
+		aliasZone.dnsKey = dns.Copy(aliasZone.dnsKey).(*dns.DNSKEY)
+		aliasZone.dnsKey.Hdr.Name = alias
+		aliasZone.rrset = aliasZone.rrset.NotNil()
+
+		fixName := func(n string) string {
+			return strings.TrimSuffix(n, z.Name()) + aliasZone.Name()
 		}
-	*/
+
+		for i, rr := range aliasZone.rrset {
+			rcopy := dns.Copy(rr)
+			rcopy.Header().Name = fixName(rcopy.Header().Name)
+
+			if ns, ok := rcopy.(*dns.NS); ok {
+				ns.Ns = fixName(ns.Ns)
+			}
+			if ns, ok := rcopy.(*dns.SOA); ok {
+				ns.Mbox = fixName(ns.Mbox)
+				ns.Ns = fixName(ns.Ns)
+			}
+			if ns, ok := rcopy.(*dns.CNAME); ok {
+				ns.Target = fixName(ns.Target)
+			}
+
+			aliasZone.rrset[i] = rcopy
+		}
+
+		//Add owner record
+		if err = aliasZone.AddRecordTXT("_owner", []string{z.Name()}, 3600*24); err != nil {
+			return nil, err
+		}
+
+		newZone, err = signOneZone(&aliasZone, aliasZone.rrset)
+		if err != nil {
+			return nil, err
+		}
+		zones = append(zones, newZone)
+
+	}
+
+	return zones, nil
+}
+
+func signOneZone(z *Zone, rrset RRSet) (*Zone, error) {
+	signSet := rrset
 
 	//Check if another ZSK key exists for zones, otherwise behave as CSK
 
 	var isKSKOnly bool
-	for _, rr := range z.rrset.Get(dns.TypeDNSKEY, z.Name()) {
+	for _, rr := range rrset.Get(dns.TypeDNSKEY, z.Name()) {
 		if k, ok := rr.(*dns.DNSKEY); ok {
 			//found ZSK key that is not ours
 			if k.Flags == 256 && k.PublicKey != z.dnsKey.PublicKey && k.Algorithm == z.dnsKey.Algorithm {
@@ -371,24 +450,29 @@ func (z *Zone) Sign() (rrsigs []*dns.RRSIG, err error) {
 
 	//only sign DNSKEY, CDNSKEY, DS, CDS as KSK
 	if isKSKOnly {
-		types = []uint16{dns.TypeDS, dns.TypeCDS, dns.TypeDNSKEY, dns.TypeCDNSKEY}
+		signSet = signSet.OnlyTypes(dns.TypeDS, dns.TypeCDS, dns.TypeDNSKEY, dns.TypeCDNSKEY)
 	}
 
-	for _, rname := range names {
-		for _, rtype := range types {
-			rrset := z.rrset.Get(rtype, rname)
-			if len(rrset) > 0 {
-				rrsig, err := z.SignRRSet(rrset)
+	zone := *z
+	zone.rrset = make(RRSet, len(rrset))
+	copy(zone.rrset, rrset)
+
+	for _, nameset := range signSet.SplitByName() {
+		for _, typeset := range nameset.SplitByType() {
+			if len(typeset) > 0 {
+				rrsig, err := z.SignRRSet(typeset)
 				if err != nil {
 					return nil, err
 				} else {
-					rrsigs = append(rrsigs, rrsig)
+					if err = zone.AddRR(rrsig); err != nil {
+						return nil, err
+					}
 				}
 			}
 		}
 	}
 
-	return rrsigs, nil
+	return &zone, nil
 }
 
 //TODO: implement NSEC or similar
@@ -426,6 +510,10 @@ func (z *Zone) Name() string {
 	return z.dnsKey.Hdr.Name
 }
 
+func (z *Zone) BaseZoneName() string {
+	return z.baseZone
+}
+
 func (z *Zone) DNSKEY() *dns.DNSKEY {
 	return z.dnsKey
 }

dns_test.go

@@ -12,21 +12,64 @@ func TestRecordSign(t *testing.T) {
 	zone := NewZoneFromPrivateKey(testZone, DecodeTorPrivateKey(testPrivateKey))
 	t.Logf("zone name %s", zone.Name())
 
-	if err := zone.AddRecordA("test."+zone.Name(), net.IPv4(1, 2, 3, 4), 3600); err != nil {
+	if err := zone.AddRecordA("test", net.IPv4(1, 2, 3, 4), 3600); err != nil {
+		t.Error(err)
+	}
+	if err := zone.AddRecordNS("@", "ns1."+zone.Name(), 3600*24); err != nil {
+		t.Error(err)
+	}
+	if err := zone.AddRecordNS("@", "ns2."+zone.Name(), 3600*24); err != nil {
+		t.Error(err)
+	}
+	if err := zone.AddRecordA("ns1", net.IPv4(1, 1, 1, 1), 3600*24); err != nil {
+		t.Error(err)
+	}
+	if err := zone.AddRecordA("ns2", net.IPv4(2, 2, 2, 2), 3600*24); err != nil {
 		t.Error(err)
 	}
 
-	rrsigs, err := zone.Sign()
+	enforcedZone := NewZoneFromPublicKey(zone.BaseZoneName(), zone.PubKey())
+	if err := enforcedZone.AddRecordSOA("@", "ns1."+zone.Name(), "mail."+zone.Name(), 31337, 10800, 3600, 604800, 3600, 3600); err != nil {
+		t.Error(err)
+	}
+
+	zone.SetEnforcedEntries(enforcedZone.GetRRSet())
+
+	zone.AddZoneAlias("testalias." + zone.BaseZoneName())
+
+	zones, err := zone.Sign()
 
 	if err != nil {
 		t.Error(err)
 	}
 
-	for _, rr := range zone.GetRRSet() {
-		t.Logf("    %s\n", rr.String())
-	}
+	for _, newZone := range zones {
+		t.Logf("====== ZONE %s ======", newZone.Name())
+		for _, rr := range newZone.GetRRSet() {
+			t.Logf("    %s\n", rr.String())
+		}
 
-	for _, rr := range rrsigs {
-		t.Logf("    %s\n", rr.String())
+		t.Logf("auto-generated GLUE records:")
+		for _, rr := range newZone.GetGlueRecords() {
+			t.Logf("GLUE:    %s\n", rr.String())
+		}
+	}
+}
+
+func TestRecordTopLevelCNAME(t *testing.T) {
+
+	zone := NewZoneFromPrivateKey(testZone, DecodeTorPrivateKey(testPrivateKey))
+	t.Logf("zone name %s", zone.Name())
+
+	if err := zone.AddRecordCNAME("@", "example.com.", 3600); err != nil {
+		t.Error(err)
+	}
+
+	_, err := zone.Sign()
+
+	if err == nil {
+		t.Error("expected CNAME error")
+	} else if err != TopLevelCNAMEError {
+		t.Error(err)
 	}
 }

rr.go

@@ -0,0 +1,121 @@
+package dns_api
+
+import "github.com/miekg/dns"
+
+type RRSet []dns.RR
+
+func (s RRSet) Get(rrt uint16, name string) (rrset RRSet) {
+	for _, rr := range s {
+		if rr != nil && (rr.Header().Rrtype == rrt || rrt == dns.TypeANY) && (rr.Header().Name == name || name == "") {
+			rrset = append(rrset, rr)
+		}
+	}
+
+	return
+}
+
+func (s RRSet) Delete(rrt uint16, name string) {
+	for i, rr := range s {
+		if rr != nil && rr.Header().Rrtype == rrt && rr.Header().Name == name {
+			s[i] = nil
+		}
+	}
+}
+
+func (s RRSet) SplitByType() (result []RRSet) {
+
+	var types []uint16
+
+	inTypes := func(i uint16) bool {
+		for _, j := range types {
+			if i == j {
+				return true
+			}
+		}
+		return false
+	}
+
+	for _, rr := range s {
+		if rr != nil && !inTypes(rr.Header().Rrtype) {
+			result = append(result, s.Get(rr.Header().Rrtype, ""))
+			types = append(types, rr.Header().Rrtype)
+		}
+	}
+
+	return
+}
+
+func (s RRSet) SplitByName() (result []RRSet) {
+	var names []string
+
+	inNames := func(i string) bool {
+		for _, j := range names {
+			if i == j {
+				return true
+			}
+		}
+		return false
+	}
+
+	for _, rr := range s {
+		if rr != nil && !inNames(rr.Header().Name) {
+			result = append(result, s.Get(dns.TypeANY, rr.Header().Name))
+			names = append(names, rr.Header().Name)
+		}
+	}
+
+	return
+}
+
+func (s RRSet) NotNil() (result RRSet) {
+	result = make(RRSet, 0, len(s))
+	for _, rr := range s {
+		if rr != nil {
+			result = append(result, rr)
+		}
+	}
+
+	return
+}
+
+func (s RRSet) RemoveTypes(disallow ...uint16) (result RRSet) {
+
+	inList := func(i uint16) bool {
+
+		for _, j := range disallow {
+			if i == j {
+				return true
+			}
+		}
+		return false
+	}
+
+	for _, rr := range s {
+		if rr != nil && !inList(rr.Header().Rrtype) {
+			result = append(result, rr)
+		}
+	}
+
+	return
+}
+
+func (s RRSet) OnlyTypes(allow ...uint16) (result RRSet) {
+
+	inList := func(i uint16) bool {
+
+		for _, j := range allow {
+			if i == j {
+				return true
+			}
+		}
+		return false
+	}
+
+	for _, rr := range s {
+		if rr != nil && inList(rr.Header().Rrtype) {
+			result = append(result, rr)
+		}
+	}
+
+	return
+}