Update github.com/miekg/dns to pick up fix for CVE-2019-19794.

I noticed this was out of date using 'snyk test' on the main repository.

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

@@ -20,13 +20,13 @@ import (
 // of $ after that are interpreted.
 func (zp *ZoneParser) generate(l lex) (RR, bool) {
 	token := l.token
-	step := 1
+	step := int64(1)
 	if i := strings.IndexByte(token, '/'); i >= 0 {
 		if i+1 == len(token) {
 			return zp.setParseError("bad step in $GENERATE range", l)
 		}
 
-		s, err := strconv.Atoi(token[i+1:])
+		s, err := strconv.ParseInt(token[i+1:], 10, 64)
 		if err != nil || s <= 0 {
 			return zp.setParseError("bad step in $GENERATE range", l)
 		}
@@ -40,20 +40,24 @@ func (zp *ZoneParser) generate(l lex) (RR, bool) {
 		return zp.setParseError("bad start-stop in $GENERATE range", l)
 	}
 
-	start, err := strconv.Atoi(sx[0])
+	start, err := strconv.ParseInt(sx[0], 10, 64)
 	if err != nil {
 		return zp.setParseError("bad start in $GENERATE range", l)
 	}
 
-	end, err := strconv.Atoi(sx[1])
+	end, err := strconv.ParseInt(sx[1], 10, 64)
 	if err != nil {
 		return zp.setParseError("bad stop in $GENERATE range", l)
 	}
-	if end < 0 || start < 0 || end < start {
+	if end < 0 || start < 0 || end < start || (end-start)/step > 65535 {
 		return zp.setParseError("bad range in $GENERATE range", l)
 	}
 
-	zp.c.Next() // _BLANK
+	// _BLANK
+	l, ok := zp.c.Next()
+	if !ok || l.value != zBlank {
+		return zp.setParseError("garbage after $GENERATE range", l)
+	}
 
 	// Create a complete new string, which we then parse again.
 	var s string
@@ -71,16 +75,17 @@ func (zp *ZoneParser) generate(l lex) (RR, bool) {
 	r := &generateReader{
 		s: s,
 
-		cur:   start,
-		start: start,
-		end:   end,
-		step:  step,
+		cur:   int(start),
+		start: int(start),
+		end:   int(end),
+		step:  int(step),
 
 		file: zp.file,
 		lex:  &l,
 	}
 	zp.sub = NewZoneParser(r, zp.origin, zp.file)
 	zp.sub.includeDepth, zp.sub.includeAllowed = zp.includeDepth, zp.includeAllowed
+	zp.sub.generateDisallowed = true
 	zp.sub.SetDefaultTTL(defaultTtl)
 	return zp.subNext()
 }
@@ -183,7 +188,7 @@ func (r *generateReader) ReadByte() (byte, error) {
 			if errMsg != "" {
 				return 0, r.parseError(errMsg, si+3+sep)
 			}
-			if r.start+offset < 0 || r.end+offset > 1<<31-1 {
+			if r.start+offset < 0 || int64(r.end) + int64(offset) > 1<<31-1 {
 				return 0, r.parseError("bad offset in $GENERATE", si+3+sep)
 			}
 
@@ -224,19 +229,19 @@ func modToPrintf(s string) (string, int, string) {
 		return "", 0, "bad base in $GENERATE"
 	}
 
-	offset, err := strconv.Atoi(offStr)
+	offset, err := strconv.ParseInt(offStr, 10, 64)
 	if err != nil {
 		return "", 0, "bad offset in $GENERATE"
 	}
 
-	width, err := strconv.Atoi(widthStr)
+	width, err := strconv.ParseInt(widthStr, 10, 64)
 	if err != nil || width < 0 || width > 255 {
 		return "", 0, "bad width in $GENERATE"
 	}
 
 	if width == 0 {
-		return "%" + base, offset, ""
+		return "%" + base, int(offset), ""
 	}
 
-	return "%0" + widthStr + base, offset, ""
+	return "%0" + widthStr + base, int(offset), ""
 }