Vendor integration dependencies.

integration/vendor/github.com/miekg/dns/scan.go

@@ -0,0 +1,974 @@
+package dns
+
+import (
+	"io"
+	"log"
+	"os"
+	"strconv"
+	"strings"
+)
+
+type debugging bool
+
+const debug debugging = false
+
+func (d debugging) Printf(format string, args ...interface{}) {
+	if d {
+		log.Printf(format, args...)
+	}
+}
+
+const maxTok = 2048 // Largest token we can return.
+const maxUint16 = 1<<16 - 1
+
+// Tokinize a RFC 1035 zone file. The tokenizer will normalize it:
+// * Add ownernames if they are left blank;
+// * Suppress sequences of spaces;
+// * Make each RR fit on one line (_NEWLINE is send as last)
+// * Handle comments: ;
+// * Handle braces - anywhere.
+const (
+	// Zonefile
+	zEOF = iota
+	zString
+	zBlank
+	zQuote
+	zNewline
+	zRrtpe
+	zOwner
+	zClass
+	zDirOrigin   // $ORIGIN
+	zDirTtl      // $TTL
+	zDirInclude  // $INCLUDE
+	zDirGenerate // $GENERATE
+
+	// Privatekey file
+	zValue
+	zKey
+
+	zExpectOwnerDir      // Ownername
+	zExpectOwnerBl       // Whitespace after the ownername
+	zExpectAny           // Expect rrtype, ttl or class
+	zExpectAnyNoClass    // Expect rrtype or ttl
+	zExpectAnyNoClassBl  // The whitespace after _EXPECT_ANY_NOCLASS
+	zExpectAnyNoTtl      // Expect rrtype or class
+	zExpectAnyNoTtlBl    // Whitespace after _EXPECT_ANY_NOTTL
+	zExpectRrtype        // Expect rrtype
+	zExpectRrtypeBl      // Whitespace BEFORE rrtype
+	zExpectRdata         // The first element of the rdata
+	zExpectDirTtlBl      // Space after directive $TTL
+	zExpectDirTtl        // Directive $TTL
+	zExpectDirOriginBl   // Space after directive $ORIGIN
+	zExpectDirOrigin     // Directive $ORIGIN
+	zExpectDirIncludeBl  // Space after directive $INCLUDE
+	zExpectDirInclude    // Directive $INCLUDE
+	zExpectDirGenerate   // Directive $GENERATE
+	zExpectDirGenerateBl // Space after directive $GENERATE
+)
+
+// ParseError is a parsing error. It contains the parse error and the location in the io.Reader
+// where the error occurred.
+type ParseError struct {
+	file string
+	err  string
+	lex  lex
+}
+
+func (e *ParseError) Error() (s string) {
+	if e.file != "" {
+		s = e.file + ": "
+	}
+	s += "dns: " + e.err + ": " + strconv.QuoteToASCII(e.lex.token) + " at line: " +
+		strconv.Itoa(e.lex.line) + ":" + strconv.Itoa(e.lex.column)
+	return
+}
+
+type lex struct {
+	token      string // text of the token
+	tokenUpper string // uppercase text of the token
+	length     int    // length of the token
+	err        bool   // when true, token text has lexer error
+	value      uint8  // value: zString, _BLANK, etc.
+	line       int    // line in the file
+	column     int    // column in the file
+	torc       uint16 // type or class as parsed in the lexer, we only need to look this up in the grammar
+	comment    string // any comment text seen
+}
+
+// Token holds the token that are returned when a zone file is parsed.
+type Token struct {
+	// The scanned resource record when error is not nil.
+	RR
+	// When an error occurred, this has the error specifics.
+	Error *ParseError
+	// A potential comment positioned after the RR and on the same line.
+	Comment string
+}
+
+// NewRR reads the RR contained in the string s. Only the first RR is
+// returned. If s contains no RR, return nil with no error. The class
+// defaults to IN and TTL defaults to 3600. The full zone file syntax
+// like $TTL, $ORIGIN, etc. is supported. All fields of the returned
+// RR are set, except RR.Header().Rdlength which is set to 0.
+func NewRR(s string) (RR, error) {
+	if len(s) > 0 && s[len(s)-1] != '\n' { // We need a closing newline
+		return ReadRR(strings.NewReader(s+"\n"), "")
+	}
+	return ReadRR(strings.NewReader(s), "")
+}
+
+// ReadRR reads the RR contained in q.
+// See NewRR for more documentation.
+func ReadRR(q io.Reader, filename string) (RR, error) {
+	r := <-parseZoneHelper(q, ".", filename, 1)
+	if r == nil {
+		return nil, nil
+	}
+
+	if r.Error != nil {
+		return nil, r.Error
+	}
+	return r.RR, nil
+}
+
+// ParseZone reads a RFC 1035 style zonefile from r. It returns *Tokens on the
+// returned channel, which consist out the parsed RR, a potential comment or an error.
+// If there is an error the RR is nil. The string file is only used
+// in error reporting. The string origin is used as the initial origin, as
+// if the file would start with: $ORIGIN origin .
+// The directives $INCLUDE, $ORIGIN, $TTL and $GENERATE are supported.
+// The channel t is closed by ParseZone when the end of r is reached.
+//
+// Basic usage pattern when reading from a string (z) containing the
+// zone data:
+//
+//	for x := range dns.ParseZone(strings.NewReader(z), "", "") {
+//		if x.Error != nil {
+//                  // log.Println(x.Error)
+//              } else {
+//                  // Do something with x.RR
+//              }
+//	}
+//
+// Comments specified after an RR (and on the same line!) are returned too:
+//
+//	foo. IN A 10.0.0.1 ; this is a comment
+//
+// The text "; this is comment" is returned in Token.Comment. Comments inside the
+// RR are discarded. Comments on a line by themselves are discarded too.
+func ParseZone(r io.Reader, origin, file string) chan *Token {
+	return parseZoneHelper(r, origin, file, 10000)
+}
+
+func parseZoneHelper(r io.Reader, origin, file string, chansize int) chan *Token {
+	t := make(chan *Token, chansize)
+	go parseZone(r, origin, file, t, 0)
+	return t
+}
+
+func parseZone(r io.Reader, origin, f string, t chan *Token, include int) {
+	defer func() {
+		if include == 0 {
+			close(t)
+		}
+	}()
+	s := scanInit(r)
+	c := make(chan lex)
+	// Start the lexer
+	go zlexer(s, c)
+	// 6 possible beginnings of a line, _ is a space
+	// 0. zRRTYPE                              -> all omitted until the rrtype
+	// 1. zOwner _ zRrtype                     -> class/ttl omitted
+	// 2. zOwner _ zString _ zRrtype           -> class omitted
+	// 3. zOwner _ zString _ zClass  _ zRrtype -> ttl/class
+	// 4. zOwner _ zClass  _ zRrtype           -> ttl omitted
+	// 5. zOwner _ zClass  _ zString _ zRrtype -> class/ttl (reversed)
+	// After detecting these, we know the zRrtype so we can jump to functions
+	// handling the rdata for each of these types.
+
+	if origin == "" {
+		origin = "."
+	}
+	origin = Fqdn(origin)
+	if _, ok := IsDomainName(origin); !ok {
+		t <- &Token{Error: &ParseError{f, "bad initial origin name", lex{}}}
+		return
+	}
+
+	st := zExpectOwnerDir // initial state
+	var h RR_Header
+	var defttl uint32 = defaultTtl
+	var prevName string
+	for l := range c {
+		// Lexer spotted an error already
+		if l.err == true {
+			t <- &Token{Error: &ParseError{f, l.token, l}}
+			return
+
+		}
+		switch st {
+		case zExpectOwnerDir:
+			// We can also expect a directive, like $TTL or $ORIGIN
+			h.Ttl = defttl
+			h.Class = ClassINET
+			switch l.value {
+			case zNewline:
+				st = zExpectOwnerDir
+			case zOwner:
+				h.Name = l.token
+				if l.token[0] == '@' {
+					h.Name = origin
+					prevName = h.Name
+					st = zExpectOwnerBl
+					break
+				}
+				if h.Name[l.length-1] != '.' {
+					h.Name = appendOrigin(h.Name, origin)
+				}
+				_, ok := IsDomainName(l.token)
+				if !ok {
+					t <- &Token{Error: &ParseError{f, "bad owner name", l}}
+					return
+				}
+				prevName = h.Name
+				st = zExpectOwnerBl
+			case zDirTtl:
+				st = zExpectDirTtlBl
+			case zDirOrigin:
+				st = zExpectDirOriginBl
+			case zDirInclude:
+				st = zExpectDirIncludeBl
+			case zDirGenerate:
+				st = zExpectDirGenerateBl
+			case zRrtpe:
+				h.Name = prevName
+				h.Rrtype = l.torc
+				st = zExpectRdata
+			case zClass:
+				h.Name = prevName
+				h.Class = l.torc
+				st = zExpectAnyNoClassBl
+			case zBlank:
+				// Discard, can happen when there is nothing on the
+				// line except the RR type
+			case zString:
+				ttl, ok := stringToTtl(l.token)
+				if !ok {
+					t <- &Token{Error: &ParseError{f, "not a TTL", l}}
+					return
+				}
+				h.Ttl = ttl
+				// Don't about the defttl, we should take the $TTL value
+				// defttl = ttl
+				st = zExpectAnyNoTtlBl
+
+			default:
+				t <- &Token{Error: &ParseError{f, "syntax error at beginning", l}}
+				return
+			}
+		case zExpectDirIncludeBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank after $INCLUDE-directive", l}}
+				return
+			}
+			st = zExpectDirInclude
+		case zExpectDirInclude:
+			if l.value != zString {
+				t <- &Token{Error: &ParseError{f, "expecting $INCLUDE value, not this...", l}}
+				return
+			}
+			neworigin := origin // There may be optionally a new origin set after the filename, if not use current one
+			l := <-c
+			switch l.value {
+			case zBlank:
+				l := <-c
+				if l.value == zString {
+					if _, ok := IsDomainName(l.token); !ok || l.length == 0 || l.err {
+						t <- &Token{Error: &ParseError{f, "bad origin name", l}}
+						return
+					}
+					// a new origin is specified.
+					if l.token[l.length-1] != '.' {
+						if origin != "." { // Prevent .. endings
+							neworigin = l.token + "." + origin
+						} else {
+							neworigin = l.token + origin
+						}
+					} else {
+						neworigin = l.token
+					}
+				}
+			case zNewline, zEOF:
+				// Ok
+			default:
+				t <- &Token{Error: &ParseError{f, "garbage after $INCLUDE", l}}
+				return
+			}
+			// Start with the new file
+			r1, e1 := os.Open(l.token)
+			if e1 != nil {
+				t <- &Token{Error: &ParseError{f, "failed to open `" + l.token + "'", l}}
+				return
+			}
+			if include+1 > 7 {
+				t <- &Token{Error: &ParseError{f, "too deeply nested $INCLUDE", l}}
+				return
+			}
+			parseZone(r1, l.token, neworigin, t, include+1)
+			st = zExpectOwnerDir
+		case zExpectDirTtlBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank after $TTL-directive", l}}
+				return
+			}
+			st = zExpectDirTtl
+		case zExpectDirTtl:
+			if l.value != zString {
+				t <- &Token{Error: &ParseError{f, "expecting $TTL value, not this...", l}}
+				return
+			}
+			if e, _ := slurpRemainder(c, f); e != nil {
+				t <- &Token{Error: e}
+				return
+			}
+			ttl, ok := stringToTtl(l.token)
+			if !ok {
+				t <- &Token{Error: &ParseError{f, "expecting $TTL value, not this...", l}}
+				return
+			}
+			defttl = ttl
+			st = zExpectOwnerDir
+		case zExpectDirOriginBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank after $ORIGIN-directive", l}}
+				return
+			}
+			st = zExpectDirOrigin
+		case zExpectDirOrigin:
+			if l.value != zString {
+				t <- &Token{Error: &ParseError{f, "expecting $ORIGIN value, not this...", l}}
+				return
+			}
+			if e, _ := slurpRemainder(c, f); e != nil {
+				t <- &Token{Error: e}
+			}
+			if _, ok := IsDomainName(l.token); !ok {
+				t <- &Token{Error: &ParseError{f, "bad origin name", l}}
+				return
+			}
+			if l.token[l.length-1] != '.' {
+				if origin != "." { // Prevent .. endings
+					origin = l.token + "." + origin
+				} else {
+					origin = l.token + origin
+				}
+			} else {
+				origin = l.token
+			}
+			st = zExpectOwnerDir
+		case zExpectDirGenerateBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank after $GENERATE-directive", l}}
+				return
+			}
+			st = zExpectDirGenerate
+		case zExpectDirGenerate:
+			if l.value != zString {
+				t <- &Token{Error: &ParseError{f, "expecting $GENERATE value, not this...", l}}
+				return
+			}
+			if errMsg := generate(l, c, t, origin); errMsg != "" {
+				t <- &Token{Error: &ParseError{f, errMsg, l}}
+				return
+			}
+			st = zExpectOwnerDir
+		case zExpectOwnerBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank after owner", l}}
+				return
+			}
+			st = zExpectAny
+		case zExpectAny:
+			switch l.value {
+			case zRrtpe:
+				h.Rrtype = l.torc
+				st = zExpectRdata
+			case zClass:
+				h.Class = l.torc
+				st = zExpectAnyNoClassBl
+			case zString:
+				ttl, ok := stringToTtl(l.token)
+				if !ok {
+					t <- &Token{Error: &ParseError{f, "not a TTL", l}}
+					return
+				}
+				h.Ttl = ttl
+				// defttl = ttl // don't set the defttl here
+				st = zExpectAnyNoTtlBl
+			default:
+				t <- &Token{Error: &ParseError{f, "expecting RR type, TTL or class, not this...", l}}
+				return
+			}
+		case zExpectAnyNoClassBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank before class", l}}
+				return
+			}
+			st = zExpectAnyNoClass
+		case zExpectAnyNoTtlBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank before TTL", l}}
+				return
+			}
+			st = zExpectAnyNoTtl
+		case zExpectAnyNoTtl:
+			switch l.value {
+			case zClass:
+				h.Class = l.torc
+				st = zExpectRrtypeBl
+			case zRrtpe:
+				h.Rrtype = l.torc
+				st = zExpectRdata
+			default:
+				t <- &Token{Error: &ParseError{f, "expecting RR type or class, not this...", l}}
+				return
+			}
+		case zExpectAnyNoClass:
+			switch l.value {
+			case zString:
+				ttl, ok := stringToTtl(l.token)
+				if !ok {
+					t <- &Token{Error: &ParseError{f, "not a TTL", l}}
+					return
+				}
+				h.Ttl = ttl
+				// defttl = ttl // don't set the def ttl anymore
+				st = zExpectRrtypeBl
+			case zRrtpe:
+				h.Rrtype = l.torc
+				st = zExpectRdata
+			default:
+				t <- &Token{Error: &ParseError{f, "expecting RR type or TTL, not this...", l}}
+				return
+			}
+		case zExpectRrtypeBl:
+			if l.value != zBlank {
+				t <- &Token{Error: &ParseError{f, "no blank before RR type", l}}
+				return
+			}
+			st = zExpectRrtype
+		case zExpectRrtype:
+			if l.value != zRrtpe {
+				t <- &Token{Error: &ParseError{f, "unknown RR type", l}}
+				return
+			}
+			h.Rrtype = l.torc
+			st = zExpectRdata
+		case zExpectRdata:
+			r, e, c1 := setRR(h, c, origin, f)
+			if e != nil {
+				// If e.lex is nil than we have encounter a unknown RR type
+				// in that case we substitute our current lex token
+				if e.lex.token == "" && e.lex.value == 0 {
+					e.lex = l // Uh, dirty
+				}
+				t <- &Token{Error: e}
+				return
+			}
+			t <- &Token{RR: r, Comment: c1}
+			st = zExpectOwnerDir
+		}
+	}
+	// If we get here, we and the h.Rrtype is still zero, we haven't parsed anything, this
+	// is not an error, because an empty zone file is still a zone file.
+}
+
+// zlexer scans the sourcefile and returns tokens on the channel c.
+func zlexer(s *scan, c chan lex) {
+	var l lex
+	str := make([]byte, maxTok) // Should be enough for any token
+	stri := 0                   // Offset in str (0 means empty)
+	com := make([]byte, maxTok) // Hold comment text
+	comi := 0
+	quote := false
+	escape := false
+	space := false
+	commt := false
+	rrtype := false
+	owner := true
+	brace := 0
+	x, err := s.tokenText()
+	defer close(c)
+	for err == nil {
+		l.column = s.position.Column
+		l.line = s.position.Line
+		if stri >= maxTok {
+			l.token = "token length insufficient for parsing"
+			l.err = true
+			debug.Printf("[%+v]", l.token)
+			c <- l
+			return
+		}
+		if comi >= maxTok {
+			l.token = "comment length insufficient for parsing"
+			l.err = true
+			debug.Printf("[%+v]", l.token)
+			c <- l
+			return
+		}
+
+		switch x {
+		case ' ', '\t':
+			if escape {
+				escape = false
+				str[stri] = x
+				stri++
+				break
+			}
+			if quote {
+				// Inside quotes this is legal
+				str[stri] = x
+				stri++
+				break
+			}
+			if commt {
+				com[comi] = x
+				comi++
+				break
+			}
+			if stri == 0 {
+				// Space directly in the beginning, handled in the grammar
+			} else if owner {
+				// If we have a string and its the first, make it an owner
+				l.value = zOwner
+				l.token = string(str[:stri])
+				l.tokenUpper = strings.ToUpper(l.token)
+				l.length = stri
+				// escape $... start with a \ not a $, so this will work
+				switch l.tokenUpper {
+				case "$TTL":
+					l.value = zDirTtl
+				case "$ORIGIN":
+					l.value = zDirOrigin
+				case "$INCLUDE":
+					l.value = zDirInclude
+				case "$GENERATE":
+					l.value = zDirGenerate
+				}
+				debug.Printf("[7 %+v]", l.token)
+				c <- l
+			} else {
+				l.value = zString
+				l.token = string(str[:stri])
+				l.tokenUpper = strings.ToUpper(l.token)
+				l.length = stri
+				if !rrtype {
+					if t, ok := StringToType[l.tokenUpper]; ok {
+						l.value = zRrtpe
+						l.torc = t
+						rrtype = true
+					} else {
+						if strings.HasPrefix(l.tokenUpper, "TYPE") {
+							t, ok := typeToInt(l.token)
+							if !ok {
+								l.token = "unknown RR type"
+								l.err = true
+								c <- l
+								return
+							}
+							l.value = zRrtpe
+							l.torc = t
+						}
+					}
+					if t, ok := StringToClass[l.tokenUpper]; ok {
+						l.value = zClass
+						l.torc = t
+					} else {
+						if strings.HasPrefix(l.tokenUpper, "CLASS") {
+							t, ok := classToInt(l.token)
+							if !ok {
+								l.token = "unknown class"
+								l.err = true
+								c <- l
+								return
+							}
+							l.value = zClass
+							l.torc = t
+						}
+					}
+				}
+				debug.Printf("[6 %+v]", l.token)
+				c <- l
+			}
+			stri = 0
+			// I reverse space stuff here
+			if !space && !commt {
+				l.value = zBlank
+				l.token = " "
+				l.length = 1
+				debug.Printf("[5 %+v]", l.token)
+				c <- l
+			}
+			owner = false
+			space = true
+		case ';':
+			if escape {
+				escape = false
+				str[stri] = x
+				stri++
+				break
+			}
+			if quote {
+				// Inside quotes this is legal
+				str[stri] = x
+				stri++
+				break
+			}
+			if stri > 0 {
+				l.value = zString
+				l.token = string(str[:stri])
+				l.length = stri
+				debug.Printf("[4 %+v]", l.token)
+				c <- l
+				stri = 0
+			}
+			commt = true
+			com[comi] = ';'
+			comi++
+		case '\r':
+			escape = false
+			if quote {
+				str[stri] = x
+				stri++
+				break
+			}
+			// discard if outside of quotes
+		case '\n':
+			escape = false
+			// Escaped newline
+			if quote {
+				str[stri] = x
+				stri++
+				break
+			}
+			// inside quotes this is legal
+			if commt {
+				// Reset a comment
+				commt = false
+				rrtype = false
+				stri = 0
+				// If not in a brace this ends the comment AND the RR
+				if brace == 0 {
+					owner = true
+					owner = true
+					l.value = zNewline
+					l.token = "\n"
+					l.length = 1
+					l.comment = string(com[:comi])
+					debug.Printf("[3 %+v %+v]", l.token, l.comment)
+					c <- l
+					l.comment = ""
+					comi = 0
+					break
+				}
+				com[comi] = ' ' // convert newline to space
+				comi++
+				break
+			}
+
+			if brace == 0 {
+				// If there is previous text, we should output it here
+				if stri != 0 {
+					l.value = zString
+					l.token = string(str[:stri])
+					l.tokenUpper = strings.ToUpper(l.token)
+
+					l.length = stri
+					if !rrtype {
+						if t, ok := StringToType[l.tokenUpper]; ok {
+							l.value = zRrtpe
+							l.torc = t
+							rrtype = true
+						}
+					}
+					debug.Printf("[2 %+v]", l.token)
+					c <- l
+				}
+				l.value = zNewline
+				l.token = "\n"
+				l.length = 1
+				debug.Printf("[1 %+v]", l.token)
+				c <- l
+				stri = 0
+				commt = false
+				rrtype = false
+				owner = true
+				comi = 0
+			}
+		case '\\':
+			// comments do not get escaped chars, everything is copied
+			if commt {
+				com[comi] = x
+				comi++
+				break
+			}
+			// something already escaped must be in string
+			if escape {
+				str[stri] = x
+				stri++
+				escape = false
+				break
+			}
+			// something escaped outside of string gets added to string
+			str[stri] = x
+			stri++
+			escape = true
+		case '"':
+			if commt {
+				com[comi] = x
+				comi++
+				break
+			}
+			if escape {
+				str[stri] = x
+				stri++
+				escape = false
+				break
+			}
+			space = false
+			// send previous gathered text and the quote
+			if stri != 0 {
+				l.value = zString
+				l.token = string(str[:stri])
+				l.length = stri
+
+				debug.Printf("[%+v]", l.token)
+				c <- l
+				stri = 0
+			}
+
+			// send quote itself as separate token
+			l.value = zQuote
+			l.token = "\""
+			l.length = 1
+			c <- l
+			quote = !quote
+		case '(', ')':
+			if commt {
+				com[comi] = x
+				comi++
+				break
+			}
+			if escape {
+				str[stri] = x
+				stri++
+				escape = false
+				break
+			}
+			if quote {
+				str[stri] = x
+				stri++
+				break
+			}
+			switch x {
+			case ')':
+				brace--
+				if brace < 0 {
+					l.token = "extra closing brace"
+					l.err = true
+					debug.Printf("[%+v]", l.token)
+					c <- l
+					return
+				}
+			case '(':
+				brace++
+			}
+		default:
+			escape = false
+			if commt {
+				com[comi] = x
+				comi++
+				break
+			}
+			str[stri] = x
+			stri++
+			space = false
+		}
+		x, err = s.tokenText()
+	}
+	if stri > 0 {
+		// Send remainder
+		l.token = string(str[:stri])
+		l.length = stri
+		l.value = zString
+		debug.Printf("[%+v]", l.token)
+		c <- l
+	}
+}
+
+// Extract the class number from CLASSxx
+func classToInt(token string) (uint16, bool) {
+	offset := 5
+	if len(token) < offset+1 {
+		return 0, false
+	}
+	class, ok := strconv.Atoi(token[offset:])
+	if ok != nil || class > maxUint16 {
+		return 0, false
+	}
+	return uint16(class), true
+}
+
+// Extract the rr number from TYPExxx
+func typeToInt(token string) (uint16, bool) {
+	offset := 4
+	if len(token) < offset+1 {
+		return 0, false
+	}
+	typ, ok := strconv.Atoi(token[offset:])
+	if ok != nil || typ > maxUint16 {
+		return 0, false
+	}
+	return uint16(typ), true
+}
+
+// Parse things like 2w, 2m, etc, Return the time in seconds.
+func stringToTtl(token string) (uint32, bool) {
+	s := uint32(0)
+	i := uint32(0)
+	for _, c := range token {
+		switch c {
+		case 's', 'S':
+			s += i
+			i = 0
+		case 'm', 'M':
+			s += i * 60
+			i = 0
+		case 'h', 'H':
+			s += i * 60 * 60
+			i = 0
+		case 'd', 'D':
+			s += i * 60 * 60 * 24
+			i = 0
+		case 'w', 'W':
+			s += i * 60 * 60 * 24 * 7
+			i = 0
+		case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
+			i *= 10
+			i += uint32(c) - '0'
+		default:
+			return 0, false
+		}
+	}
+	return s + i, true
+}
+
+// Parse LOC records' <digits>[.<digits>][mM] into a
+// mantissa exponent format. Token should contain the entire
+// string (i.e. no spaces allowed)
+func stringToCm(token string) (e, m uint8, ok bool) {
+	if token[len(token)-1] == 'M' || token[len(token)-1] == 'm' {
+		token = token[0 : len(token)-1]
+	}
+	s := strings.SplitN(token, ".", 2)
+	var meters, cmeters, val int
+	var err error
+	switch len(s) {
+	case 2:
+		if cmeters, err = strconv.Atoi(s[1]); err != nil {
+			return
+		}
+		fallthrough
+	case 1:
+		if meters, err = strconv.Atoi(s[0]); err != nil {
+			return
+		}
+	case 0:
+		// huh?
+		return 0, 0, false
+	}
+	ok = true
+	if meters > 0 {
+		e = 2
+		val = meters
+	} else {
+		e = 0
+		val = cmeters
+	}
+	for val > 10 {
+		e++
+		val /= 10
+	}
+	if e > 9 {
+		ok = false
+	}
+	m = uint8(val)
+	return
+}
+
+func appendOrigin(name, origin string) string {
+	if origin == "." {
+		return name + origin
+	}
+	return name + "." + origin
+}
+
+// LOC record helper function
+func locCheckNorth(token string, latitude uint32) (uint32, bool) {
+	switch token {
+	case "n", "N":
+		return LOC_EQUATOR + latitude, true
+	case "s", "S":
+		return LOC_EQUATOR - latitude, true
+	}
+	return latitude, false
+}
+
+// LOC record helper function
+func locCheckEast(token string, longitude uint32) (uint32, bool) {
+	switch token {
+	case "e", "E":
+		return LOC_EQUATOR + longitude, true
+	case "w", "W":
+		return LOC_EQUATOR - longitude, true
+	}
+	return longitude, false
+}
+
+// "Eat" the rest of the "line". Return potential comments
+func slurpRemainder(c chan lex, f string) (*ParseError, string) {
+	l := <-c
+	com := ""
+	switch l.value {
+	case zBlank:
+		l = <-c
+		com = l.comment
+		if l.value != zNewline && l.value != zEOF {
+			return &ParseError{f, "garbage after rdata", l}, ""
+		}
+	case zNewline:
+		com = l.comment
+	case zEOF:
+	default:
+		return &ParseError{f, "garbage after rdata", l}, ""
+	}
+	return nil, com
+}
+
+// Parse a 64 bit-like ipv6 address: "0014:4fff:ff20:ee64"
+// Used for NID and L64 record.
+func stringToNodeID(l lex) (uint64, *ParseError) {
+	if len(l.token) < 19 {
+		return 0, &ParseError{l.token, "bad NID/L64 NodeID/Locator64", l}
+	}
+	// There must be three colons at fixes postitions, if not its a parse error
+	if l.token[4] != ':' && l.token[9] != ':' && l.token[14] != ':' {
+		return 0, &ParseError{l.token, "bad NID/L64 NodeID/Locator64", l}
+	}
+	s := l.token[0:4] + l.token[5:9] + l.token[10:14] + l.token[15:19]
+	u, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return 0, &ParseError{l.token, "bad NID/L64 NodeID/Locator64", l}
+	}
+	return u, nil
+}