@ -130,7 +130,7 @@ func escapeUrlComponent(w stringWriterWriter, val string) error {
return err
}
// Query represents a query
// Query represents a single part of the query string, a query param
type Query struct {
Key string
Value string
@ -138,6 +138,10 @@ type Query struct {
}
func parseQuery ( query string ) ( values [ ] Query , err error ) {
// This is essentially a copy of parseQuery from
// https://golang.org/src/net/url/url.go but adjusted to build our values
// based on our type, which we need to preserve the ordering of the query
// string
for query != "" {
key := query
if i := strings . IndexAny ( key , "&;" ) ; i >= 0 {
@ -213,43 +217,6 @@ func sanitizedURL(val string) (string, error) {
return u . String ( ) , nil
}
func ( p * Policy ) writeLinkableBuf ( buff stringWriterWriter , token * html . Token ) ( int , error ) {
// do not escape multiple query parameters
tokenBuff := bytes . NewBuffer ( make ( [ ] byte , 0 , 1024 ) ) // This should stay on the stack unless it gets too big
tokenBuff . WriteByte ( '<' )
tokenBuff . WriteString ( token . Data )
for _ , attr := range token . Attr {
tokenBuff . WriteByte ( ' ' )
tokenBuff . WriteString ( attr . Key )
tokenBuff . Write ( [ ] byte { '=' , '"' } )
switch attr . Key {
case "href" , "src" :
u , ok := p . validURL ( attr . Val )
if ! ok {
tokenBuff . WriteString ( html . EscapeString ( attr . Val ) )
continue
}
u , err := sanitizedURL ( u )
if err == nil {
tokenBuff . WriteString ( u )
} else {
// fallthrough
tokenBuff . WriteString ( html . EscapeString ( attr . Val ) )
}
default :
// re-apply
tokenBuff . WriteString ( html . EscapeString ( attr . Val ) )
}
tokenBuff . WriteByte ( '"' )
}
if token . Type == html . SelfClosingTagToken {
tokenBuff . WriteString ( "/" )
}
tokenBuff . WriteString ( ">" )
return buff . Write ( tokenBuff . Bytes ( ) )
}
// Performs the actual sanitization process.
func ( p * Policy ) sanitizeWithBuff ( r io . Reader ) * bytes . Buffer {
var buff bytes . Buffer
@ -344,7 +311,9 @@ func (p *Policy) sanitize(r io.Reader, w io.Writer) error {
aps = aa
}
if len ( token . Attr ) != 0 {
token . Attr = p . sanitizeAttrs ( token . Data , token . Attr , aps )
token . Attr = escapeAttributes (
p . sanitizeAttrs ( token . Data , token . Attr , aps ) ,
)
}
if len ( token . Attr ) == 0 {
@ -361,15 +330,8 @@ func (p *Policy) sanitize(r io.Reader, w io.Writer) error {
}
if ! skipElementContent {
// do not escape multiple query parameters
if linkable ( token . Data ) {
if _ , err := p . writeLinkableBuf ( buff , & token ) ; err != nil {
return err
}
} else {
if _ , err := buff . WriteString ( token . String ( ) ) ; err != nil {
return err
}
if _ , err := buff . WriteString ( token . String ( ) ) ; err != nil {
return err
}
}
@ -439,7 +401,7 @@ func (p *Policy) sanitize(r io.Reader, w io.Writer) error {
}
if len ( token . Attr ) != 0 {
token . Attr = p . sanitizeAttrs ( token . Data , token . Attr , aps )
token . Attr = escapeAttributes ( p . sanitizeAttrs ( token . Data , token . Attr , aps ) )
}
if len ( token . Attr ) == 0 && ! p . allowNoAttrs ( token . Data ) {
@ -451,15 +413,8 @@ func (p *Policy) sanitize(r io.Reader, w io.Writer) error {
}
}
if ! skipElementContent {
// do not escape multiple query parameters
if linkable ( token . Data ) {
if _ , err := p . writeLinkableBuf ( buff , & token ) ; err != nil {
return err
}
} else {
if _ , err := buff . WriteString ( token . String ( ) ) ; err != nil {
return err
}
if _ , err := buff . WriteString ( token . String ( ) ) ; err != nil {
return err
}
}
@ -569,9 +524,11 @@ attrsLoop:
for _ , ap := range apl {
if ap . regexp != nil {
if ap . regexp . MatchString ( htmlAttr . Val ) {
htmlAttr . Val = escapeAttribute ( htmlAttr . Val )
cleanAttrs = append ( cleanAttrs , htmlAttr )
}
} else {
htmlAttr . Val = escapeAttribute ( htmlAttr . Val )
cleanAttrs = append ( cleanAttrs , htmlAttr )
}
}
@ -1087,3 +1044,18 @@ func normaliseElementName(str string) string {
` " ` ,
)
}
func escapeAttributes ( attrs [ ] html . Attribute ) [ ] html . Attribute {
escapedAttrs := [ ] html . Attribute { }
for _ , attr := range attrs {
attr . Val = escapeAttribute ( attr . Val )
escapedAttrs = append ( escapedAttrs , attr )
}
return escapedAttrs
}
func escapeAttribute ( val string ) string {
val = strings . Replace ( val , string ( [ ] rune { '\u00A0' } ) , ` ` , - 1 )
val = strings . Replace ( val , ` " ` , ` " ` , - 1 )
return val
}
6543
3 years ago
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