Documentation

Need to think about the non-existing root-label and the label
functions.

dnssec.go

@@ -5,6 +5,13 @@
 // DNSSEC (DNS Security Extension) adds a layer of security to the DNS. It
 // uses public key cryptography to securely sign resource records. The
 // public keys are stored in DNSKEY records and the signatures in RRSIG records.
+//
+// Requesting DNSSEC information for a zone is done by adding the DO (DNSSEC OK) bit
+// to an request.
+// 
+//      // Set UDP bufsize to 4096 and enable the DO bit
+//      m := new(dns.Msg)
+//      m.SetEdns0(4096, true)
 package dns
 
 import (

label_test.go

@@ -27,6 +27,10 @@ func TestCompareLabels(t *testing.T) {
 		t.Logf("%s with %s should be %d", s1, s5, 1)
 		t.Fail()
 	}
+	if CompareLabels(".", ".") != 1 {
+		t.Logf("%s with %s should be %d", ".", ".", 1)
+		t.Fail()
+	}
 }
 
 func TestSplitLabels(t *testing.T) {
@@ -51,4 +55,9 @@ func TestSplitLabels(t *testing.T) {
 		t.Logf("Labels should be 3, %s\n", s4)
 		t.Fail()
 	}
+        // Should this be 1 or 0...
+	if len(SplitLabels(".")) != 1 {
+		t.Logf("Labels should be 1, %s\n", ".")
+		t.Fail()
+	}
 }

labels.go

@@ -3,6 +3,8 @@ package dns
 // Holds a bunch of helper functions for dealing with labels.
 
 // SplitLabels splits a domainname string into its labels.
+// www.miek.nl. returns []string{"www", "miek", "nl"}
+// . returns []string{"."}
 func SplitLabels(s string) []string {
 	k := 0
 	labels := make([]string, 0)
@@ -30,8 +32,11 @@ func SplitLabels(s string) []string {
 // returns how many labels they have in common starting from the right.
 // The comparison stops at the first inequality.
 //
-// www.miek.nl and miek.nl have two labels in common: miek and nl
-// www.miek.nl and www.bla.nl have one label in common: nl
+// www.miek.nl. and miek.nl. have two labels in common: miek and nl
+// www.miek.nl. and www.bla.nl. have one label in common: nl
+// Be aware of these corner cases:
+// . and . have one label in common
+// . and "" (empty) have one label in common
 func CompareLabels(s1, s2 string) (n int) {
 	l1 := SplitLabels(s1)
 	l2 := SplitLabels(s2)