Update deps

vendor/github.com/miekg/dns/msg_helpers.go

@@ -495,7 +495,7 @@ Option:
 func packDataOpt(options []EDNS0, msg []byte, off int) (int, error) {
 	for _, el := range options {
 		b, err := el.pack()
-		if err != nil || off+3 > len(msg) {
+		if err != nil || off+4 > len(msg) {
 			return len(msg), &Error{err: "overflow packing opt"}
 		}
 		binary.BigEndian.PutUint16(msg[off:], el.Option())      // Option code
@@ -587,6 +587,29 @@ func unpackDataNsec(msg []byte, off int) ([]uint16, int, error) {
 	return nsec, off, nil
 }
 
+// typeBitMapLen is a helper function which computes the "maximum" length of
+// a the NSEC Type BitMap field.
+func typeBitMapLen(bitmap []uint16) int {
+	var l int
+	var lastwindow, lastlength uint16
+	for _, t := range bitmap {
+		window := t / 256
+		length := (t-window*256)/8 + 1
+		if window > lastwindow && lastlength != 0 { // New window, jump to the new offset
+			l += int(lastlength) + 2
+			lastlength = 0
+		}
+		if window < lastwindow || length < lastlength {
+			// packDataNsec would return Error{err: "nsec bits out of order"} here, but
+			// when computing the length, we want do be liberal.
+			continue
+		}
+		lastwindow, lastlength = window, length
+	}
+	l += int(lastlength) + 2
+	return l
+}
+
 func packDataNsec(bitmap []uint16, msg []byte, off int) (int, error) {
 	if len(bitmap) == 0 {
 		return off, nil