Bump deps

vendor/github.com/aymerick/douceur/LICENSE

@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2015 Aymerick JEHANNE
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+

vendor/github.com/aymerick/douceur/css/declaration.go

@@ -0,0 +1,60 @@
+package css
+
+import "fmt"
+
+// Declaration represents a parsed style property
+type Declaration struct {
+	Property  string
+	Value     string
+	Important bool
+}
+
+// NewDeclaration instanciates a new Declaration
+func NewDeclaration() *Declaration {
+	return &Declaration{}
+}
+
+// Returns string representation of the Declaration
+func (decl *Declaration) String() string {
+	return decl.StringWithImportant(true)
+}
+
+// StringWithImportant returns string representation with optional !important part
+func (decl *Declaration) StringWithImportant(option bool) string {
+	result := fmt.Sprintf("%s: %s", decl.Property, decl.Value)
+
+	if option && decl.Important {
+		result += " !important"
+	}
+
+	result += ";"
+
+	return result
+}
+
+// Equal returns true if both Declarations are equals
+func (decl *Declaration) Equal(other *Declaration) bool {
+	return (decl.Property == other.Property) && (decl.Value == other.Value) && (decl.Important == other.Important)
+}
+
+//
+// DeclarationsByProperty
+//
+
+// DeclarationsByProperty represents sortable style declarations
+type DeclarationsByProperty []*Declaration
+
+// Implements sort.Interface
+func (declarations DeclarationsByProperty) Len() int {
+	return len(declarations)
+}
+
+// Implements sort.Interface
+func (declarations DeclarationsByProperty) Swap(i, j int) {
+	declarations[i], declarations[j] = declarations[j], declarations[i]
+}
+
+// Implements sort.Interface
+func (declarations DeclarationsByProperty) Less(i, j int) bool {
+	return declarations[i].Property < declarations[j].Property
+}

vendor/github.com/aymerick/douceur/css/rule.go

@@ -0,0 +1,230 @@
+package css
+
+import (
+	"fmt"
+	"strings"
+)
+
+const (
+	indentSpace = 2
+)
+
+// RuleKind represents a Rule kind
+type RuleKind int
+
+// Rule kinds
+const (
+	QualifiedRule RuleKind = iota
+	AtRule
+)
+
+// At Rules than have Rules inside their block instead of Declarations
+var atRulesWithRulesBlock = []string{
+	"@document", "@font-feature-values", "@keyframes", "@media", "@supports",
+}
+
+// Rule represents a parsed CSS rule
+type Rule struct {
+	Kind RuleKind
+
+	// At Rule name (eg: "@media")
+	Name string
+
+	// Raw prelude
+	Prelude string
+
+	// Qualified Rule selectors parsed from prelude
+	Selectors []string
+
+	// Style properties
+	Declarations []*Declaration
+
+	// At Rule embedded rules
+	Rules []*Rule
+
+	// Current rule embedding level
+	EmbedLevel int
+}
+
+// NewRule instanciates a new Rule
+func NewRule(kind RuleKind) *Rule {
+	return &Rule{
+		Kind: kind,
+	}
+}
+
+// Returns string representation of rule kind
+func (kind RuleKind) String() string {
+	switch kind {
+	case QualifiedRule:
+		return "Qualified Rule"
+	case AtRule:
+		return "At Rule"
+	default:
+		return "WAT"
+	}
+}
+
+// EmbedsRules returns true if this rule embeds another rules
+func (rule *Rule) EmbedsRules() bool {
+	if rule.Kind == AtRule {
+		for _, atRuleName := range atRulesWithRulesBlock {
+			if rule.Name == atRuleName {
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// Equal returns true if both rules are equals
+func (rule *Rule) Equal(other *Rule) bool {
+	if (rule.Kind != other.Kind) ||
+		(rule.Prelude != other.Prelude) ||
+		(rule.Name != other.Name) {
+		return false
+	}
+
+	if (len(rule.Selectors) != len(other.Selectors)) ||
+		(len(rule.Declarations) != len(other.Declarations)) ||
+		(len(rule.Rules) != len(other.Rules)) {
+		return false
+	}
+
+	for i, sel := range rule.Selectors {
+		if sel != other.Selectors[i] {
+			return false
+		}
+	}
+
+	for i, decl := range rule.Declarations {
+		if !decl.Equal(other.Declarations[i]) {
+			return false
+		}
+	}
+
+	for i, rule := range rule.Rules {
+		if !rule.Equal(other.Rules[i]) {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Diff returns a string representation of rules differences
+func (rule *Rule) Diff(other *Rule) []string {
+	result := []string{}
+
+	if rule.Kind != other.Kind {
+		result = append(result, fmt.Sprintf("Kind: %s | %s", rule.Kind.String(), other.Kind.String()))
+	}
+
+	if rule.Prelude != other.Prelude {
+		result = append(result, fmt.Sprintf("Prelude: \"%s\" | \"%s\"", rule.Prelude, other.Prelude))
+	}
+
+	if rule.Name != other.Name {
+		result = append(result, fmt.Sprintf("Name: \"%s\" | \"%s\"", rule.Name, other.Name))
+	}
+
+	if len(rule.Selectors) != len(other.Selectors) {
+		result = append(result, fmt.Sprintf("Selectors: %v | %v", strings.Join(rule.Selectors, ", "), strings.Join(other.Selectors, ", ")))
+	} else {
+		for i, sel := range rule.Selectors {
+			if sel != other.Selectors[i] {
+				result = append(result, fmt.Sprintf("Selector: \"%s\" | \"%s\"", sel, other.Selectors[i]))
+			}
+		}
+	}
+
+	if len(rule.Declarations) != len(other.Declarations) {
+		result = append(result, fmt.Sprintf("Declarations Nb: %d | %d", len(rule.Declarations), len(other.Declarations)))
+	} else {
+		for i, decl := range rule.Declarations {
+			if !decl.Equal(other.Declarations[i]) {
+				result = append(result, fmt.Sprintf("Declaration: \"%s\" | \"%s\"", decl.String(), other.Declarations[i].String()))
+			}
+		}
+	}
+
+	if len(rule.Rules) != len(other.Rules) {
+		result = append(result, fmt.Sprintf("Rules Nb: %d | %d", len(rule.Rules), len(other.Rules)))
+	} else {
+
+		for i, rule := range rule.Rules {
+			if !rule.Equal(other.Rules[i]) {
+				result = append(result, fmt.Sprintf("Rule: \"%s\" | \"%s\"", rule.String(), other.Rules[i].String()))
+			}
+		}
+	}
+
+	return result
+}
+
+// Returns the string representation of a rule
+func (rule *Rule) String() string {
+	result := ""
+
+	if rule.Kind == QualifiedRule {
+		for i, sel := range rule.Selectors {
+			if i != 0 {
+				result += ", "
+			}
+			result += sel
+		}
+	} else {
+		// AtRule
+		result += fmt.Sprintf("%s", rule.Name)
+
+		if rule.Prelude != "" {
+			if result != "" {
+				result += " "
+			}
+			result += fmt.Sprintf("%s", rule.Prelude)
+		}
+	}
+
+	if (len(rule.Declarations) == 0) && (len(rule.Rules) == 0) {
+		result += ";"
+	} else {
+		result += " {\n"
+
+		if rule.EmbedsRules() {
+			for _, subRule := range rule.Rules {
+				result += fmt.Sprintf("%s%s\n", rule.indent(), subRule.String())
+			}
+		} else {
+			for _, decl := range rule.Declarations {
+				result += fmt.Sprintf("%s%s\n", rule.indent(), decl.String())
+			}
+		}
+
+		result += fmt.Sprintf("%s}", rule.indentEndBlock())
+	}
+
+	return result
+}
+
+// Returns identation spaces for declarations and rules
+func (rule *Rule) indent() string {
+	result := ""
+
+	for i := 0; i < ((rule.EmbedLevel + 1) * indentSpace); i++ {
+		result += " "
+	}
+
+	return result
+}
+
+// Returns identation spaces for end of block character
+func (rule *Rule) indentEndBlock() string {
+	result := ""
+
+	for i := 0; i < (rule.EmbedLevel * indentSpace); i++ {
+		result += " "
+	}
+
+	return result
+}

vendor/github.com/aymerick/douceur/css/stylesheet.go

@@ -0,0 +1,25 @@
+package css
+
+// Stylesheet represents a parsed stylesheet
+type Stylesheet struct {
+	Rules []*Rule
+}
+
+// NewStylesheet instanciate a new Stylesheet
+func NewStylesheet() *Stylesheet {
+	return &Stylesheet{}
+}
+
+// Returns string representation of the Stylesheet
+func (sheet *Stylesheet) String() string {
+	result := ""
+
+	for _, rule := range sheet.Rules {
+		if result != "" {
+			result += "\n"
+		}
+		result += rule.String()
+	}
+
+	return result
+}

vendor/github.com/aymerick/douceur/parser/parser.go

@@ -0,0 +1,409 @@
+package parser
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"strings"
+
+	"github.com/gorilla/css/scanner"
+
+	"github.com/aymerick/douceur/css"
+)
+
+const (
+	importantSuffixRegexp = `(?i)\s*!important\s*$`
+)
+
+var (
+	importantRegexp *regexp.Regexp
+)
+
+// Parser represents a CSS parser
+type Parser struct {
+	scan *scanner.Scanner // Tokenizer
+
+	// Tokens parsed but not consumed yet
+	tokens []*scanner.Token
+
+	// Rule embedding level
+	embedLevel int
+}
+
+func init() {
+	importantRegexp = regexp.MustCompile(importantSuffixRegexp)
+}
+
+// NewParser instanciates a new parser
+func NewParser(txt string) *Parser {
+	return &Parser{
+		scan: scanner.New(txt),
+	}
+}
+
+// Parse parses a whole stylesheet
+func Parse(text string) (*css.Stylesheet, error) {
+	result, err := NewParser(text).ParseStylesheet()
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+// ParseDeclarations parses CSS declarations
+func ParseDeclarations(text string) ([]*css.Declaration, error) {
+	result, err := NewParser(text).ParseDeclarations()
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
+}
+
+// ParseStylesheet parses a stylesheet
+func (parser *Parser) ParseStylesheet() (*css.Stylesheet, error) {
+	result := css.NewStylesheet()
+
+	// Parse BOM
+	if _, err := parser.parseBOM(); err != nil {
+		return result, err
+	}
+
+	// Parse list of rules
+	rules, err := parser.ParseRules()
+	if err != nil {
+		return result, err
+	}
+
+	result.Rules = rules
+
+	return result, nil
+}
+
+// ParseRules parses a list of rules
+func (parser *Parser) ParseRules() ([]*css.Rule, error) {
+	result := []*css.Rule{}
+
+	inBlock := false
+	if parser.tokenChar("{") {
+		// parsing a block of rules
+		inBlock = true
+		parser.embedLevel++
+
+		parser.shiftToken()
+	}
+
+	for parser.tokenParsable() {
+		if parser.tokenIgnorable() {
+			parser.shiftToken()
+		} else if parser.tokenChar("}") {
+			if !inBlock {
+				errMsg := fmt.Sprintf("Unexpected } character: %s", parser.nextToken().String())
+				return result, errors.New(errMsg)
+			}
+
+			parser.shiftToken()
+			parser.embedLevel--
+
+			// finished
+			break
+		} else {
+			rule, err := parser.ParseRule()
+			if err != nil {
+				return result, err
+			}
+
+			rule.EmbedLevel = parser.embedLevel
+			result = append(result, rule)
+		}
+	}
+
+	return result, parser.err()
+}
+
+// ParseRule parses a rule
+func (parser *Parser) ParseRule() (*css.Rule, error) {
+	if parser.tokenAtKeyword() {
+		return parser.parseAtRule()
+	}
+
+	return parser.parseQualifiedRule()
+}
+
+// ParseDeclarations parses a list of declarations
+func (parser *Parser) ParseDeclarations() ([]*css.Declaration, error) {
+	result := []*css.Declaration{}
+
+	if parser.tokenChar("{") {
+		parser.shiftToken()
+	}
+
+	for parser.tokenParsable() {
+		if parser.tokenIgnorable() {
+			parser.shiftToken()
+		} else if parser.tokenChar("}") {
+			// end of block
+			parser.shiftToken()
+			break
+		} else {
+			declaration, err := parser.ParseDeclaration()
+			if err != nil {
+				return result, err
+			}
+
+			result = append(result, declaration)
+		}
+	}
+
+	return result, parser.err()
+}
+
+// ParseDeclaration parses a declaration
+func (parser *Parser) ParseDeclaration() (*css.Declaration, error) {
+	result := css.NewDeclaration()
+	curValue := ""
+
+	for parser.tokenParsable() {
+		if parser.tokenChar(":") {
+			result.Property = strings.TrimSpace(curValue)
+			curValue = ""
+
+			parser.shiftToken()
+		} else if parser.tokenChar(";") || parser.tokenChar("}") {
+			if result.Property == "" {
+				errMsg := fmt.Sprintf("Unexpected ; character: %s", parser.nextToken().String())
+				return result, errors.New(errMsg)
+			}
+
+			if importantRegexp.MatchString(curValue) {
+				result.Important = true
+				curValue = importantRegexp.ReplaceAllString(curValue, "")
+			}
+
+			result.Value = strings.TrimSpace(curValue)
+
+			if parser.tokenChar(";") {
+				parser.shiftToken()
+			}
+
+			// finished
+			break
+		} else {
+			token := parser.shiftToken()
+			curValue += token.Value
+		}
+	}
+
+	// log.Printf("[parsed] Declaration: %s", result.String())
+
+	return result, parser.err()
+}
+
+// Parse an At Rule
+func (parser *Parser) parseAtRule() (*css.Rule, error) {
+	// parse rule name (eg: "@import")
+	token := parser.shiftToken()
+
+	result := css.NewRule(css.AtRule)
+	result.Name = token.Value
+
+	for parser.tokenParsable() {
+		if parser.tokenChar(";") {
+			parser.shiftToken()
+
+			// finished
+			break
+		} else if parser.tokenChar("{") {
+			if result.EmbedsRules() {
+				// parse rules block
+				rules, err := parser.ParseRules()
+				if err != nil {
+					return result, err
+				}
+
+				result.Rules = rules
+			} else {
+				// parse declarations block
+				declarations, err := parser.ParseDeclarations()
+				if err != nil {
+					return result, err
+				}
+
+				result.Declarations = declarations
+			}
+
+			// finished
+			break
+		} else {
+			// parse prelude
+			prelude, err := parser.parsePrelude()
+			if err != nil {
+				return result, err
+			}
+
+			result.Prelude = prelude
+		}
+	}
+
+	// log.Printf("[parsed] Rule: %s", result.String())
+
+	return result, parser.err()
+}
+
+// Parse a Qualified Rule
+func (parser *Parser) parseQualifiedRule() (*css.Rule, error) {
+	result := css.NewRule(css.QualifiedRule)
+
+	for parser.tokenParsable() {
+		if parser.tokenChar("{") {
+			if result.Prelude == "" {
+				errMsg := fmt.Sprintf("Unexpected { character: %s", parser.nextToken().String())
+				return result, errors.New(errMsg)
+			}
+
+			// parse declarations block
+			declarations, err := parser.ParseDeclarations()
+			if err != nil {
+				return result, err
+			}
+
+			result.Declarations = declarations
+
+			// finished
+			break
+		} else {
+			// parse prelude
+			prelude, err := parser.parsePrelude()
+			if err != nil {
+				return result, err
+			}
+
+			result.Prelude = prelude
+		}
+	}
+
+	result.Selectors = strings.Split(result.Prelude, ",")
+	for i, sel := range result.Selectors {
+		result.Selectors[i] = strings.TrimSpace(sel)
+	}
+
+	// log.Printf("[parsed] Rule: %s", result.String())
+
+	return result, parser.err()
+}
+
+// Parse Rule prelude
+func (parser *Parser) parsePrelude() (string, error) {
+	result := ""
+
+	for parser.tokenParsable() && !parser.tokenEndOfPrelude() {
+		token := parser.shiftToken()
+		result += token.Value
+	}
+
+	result = strings.TrimSpace(result)
+
+	// log.Printf("[parsed] prelude: %s", result)
+
+	return result, parser.err()
+}
+
+// Parse BOM
+func (parser *Parser) parseBOM() (bool, error) {
+	if parser.nextToken().Type == scanner.TokenBOM {
+		parser.shiftToken()
+		return true, nil
+	}
+
+	return false, parser.err()
+}
+
+// Returns next token without removing it from tokens buffer
+func (parser *Parser) nextToken() *scanner.Token {
+	if len(parser.tokens) == 0 {
+		// fetch next token
+		nextToken := parser.scan.Next()
+
+		// log.Printf("[token] %s => %v", nextToken.Type.String(), nextToken.Value)
+
+		// queue it
+		parser.tokens = append(parser.tokens, nextToken)
+	}
+
+	return parser.tokens[0]
+}
+
+// Returns next token and remove it from the tokens buffer
+func (parser *Parser) shiftToken() *scanner.Token {
+	var result *scanner.Token
+
+	result, parser.tokens = parser.tokens[0], parser.tokens[1:]
+	return result
+}
+
+// Returns tokenizer error, or nil if no error
+func (parser *Parser) err() error {
+	if parser.tokenError() {
+		token := parser.nextToken()
+		return fmt.Errorf("Tokenizer error: %s", token.String())
+	}
+
+	return nil
+}
+
+// Returns true if next token is Error
+func (parser *Parser) tokenError() bool {
+	return parser.nextToken().Type == scanner.TokenError
+}
+
+// Returns true if next token is EOF
+func (parser *Parser) tokenEOF() bool {
+	return parser.nextToken().Type == scanner.TokenEOF
+}
+
+// Returns true if next token is a whitespace
+func (parser *Parser) tokenWS() bool {
+	return parser.nextToken().Type == scanner.TokenS
+}
+
+// Returns true if next token is a comment
+func (parser *Parser) tokenComment() bool {
+	return parser.nextToken().Type == scanner.TokenComment
+}
+
+// Returns true if next token is a CDO or a CDC
+func (parser *Parser) tokenCDOorCDC() bool {
+	switch parser.nextToken().Type {
+	case scanner.TokenCDO, scanner.TokenCDC:
+		return true
+	default:
+		return false
+	}
+}
+
+// Returns true if next token is ignorable
+func (parser *Parser) tokenIgnorable() bool {
+	return parser.tokenWS() || parser.tokenComment() || parser.tokenCDOorCDC()
+}
+
+// Returns true if next token is parsable
+func (parser *Parser) tokenParsable() bool {
+	return !parser.tokenEOF() && !parser.tokenError()
+}
+
+// Returns true if next token is an At Rule keyword
+func (parser *Parser) tokenAtKeyword() bool {
+	return parser.nextToken().Type == scanner.TokenAtKeyword
+}
+
+// Returns true if next token is given character
+func (parser *Parser) tokenChar(value string) bool {
+	token := parser.nextToken()
+	return (token.Type == scanner.TokenChar) && (token.Value == value)
+}
+
+// Returns true if next token marks the end of a prelude
+func (parser *Parser) tokenEndOfPrelude() bool {
+	return parser.tokenChar(";") || parser.tokenChar("{")
+}

vendor/github.com/gorilla/css/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2013, Gorilla web toolkit
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+  Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+  Redistributions in binary form must reproduce the above copyright notice, this
+  list of conditions and the following disclaimer in the documentation and/or
+  other materials provided with the distribution.
+
+  Neither the name of the {organization} nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/css/scanner/doc.go

@@ -0,0 +1,33 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package gorilla/css/scanner generates tokens for a CSS3 input.
+
+It follows the CSS3 specification located at:
+
+	http://www.w3.org/TR/css3-syntax/
+
+To use it, create a new scanner for a given CSS string and call Next() until
+the token returned has type TokenEOF or TokenError:
+
+	s := scanner.New(myCSS)
+	for {
+		token := s.Next()
+		if token.Type == scanner.TokenEOF || token.Type == scanner.TokenError {
+			break
+		}
+		// Do something with the token...
+	}
+
+Following the CSS3 specification, an error can only occur when the scanner
+finds an unclosed quote or unclosed comment. In these cases the text becomes
+"untokenizable". Everything else is tokenizable and it is up to a parser
+to make sense of the token stream (or ignore nonsensical token sequences).
+
+Note: the scanner doesn't perform lexical analysis or, in other words, it
+doesn't care about the token context. It is intended to be used by a
+lexer or parser.
+*/
+package scanner

vendor/github.com/gorilla/css/scanner/scanner.go

@@ -0,0 +1,356 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package scanner
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"unicode"
+	"unicode/utf8"
+)
+
+// tokenType identifies the type of lexical tokens.
+type tokenType int
+
+// String returns a string representation of the token type.
+func (t tokenType) String() string {
+	return tokenNames[t]
+}
+
+// Token represents a token and the corresponding string.
+type Token struct {
+	Type   tokenType
+	Value  string
+	Line   int
+	Column int
+}
+
+// String returns a string representation of the token.
+func (t *Token) String() string {
+	if len(t.Value) > 10 {
+		return fmt.Sprintf("%s (line: %d, column: %d): %.10q...",
+			t.Type, t.Line, t.Column, t.Value)
+	}
+	return fmt.Sprintf("%s (line: %d, column: %d): %q",
+		t.Type, t.Line, t.Column, t.Value)
+}
+
+// All tokens -----------------------------------------------------------------
+
+// The complete list of tokens in CSS3.
+const (
+	// Scanner flags.
+	TokenError tokenType = iota
+	TokenEOF
+	// From now on, only tokens from the CSS specification.
+	TokenIdent
+	TokenAtKeyword
+	TokenString
+	TokenHash
+	TokenNumber
+	TokenPercentage
+	TokenDimension
+	TokenURI
+	TokenUnicodeRange
+	TokenCDO
+	TokenCDC
+	TokenS
+	TokenComment
+	TokenFunction
+	TokenIncludes
+	TokenDashMatch
+	TokenPrefixMatch
+	TokenSuffixMatch
+	TokenSubstringMatch
+	TokenChar
+	TokenBOM
+)
+
+// tokenNames maps tokenType's to their names. Used for conversion to string.
+var tokenNames = map[tokenType]string{
+	TokenError:          "error",
+	TokenEOF:            "EOF",
+	TokenIdent:          "IDENT",
+	TokenAtKeyword:      "ATKEYWORD",
+	TokenString:         "STRING",
+	TokenHash:           "HASH",
+	TokenNumber:         "NUMBER",
+	TokenPercentage:     "PERCENTAGE",
+	TokenDimension:      "DIMENSION",
+	TokenURI:            "URI",
+	TokenUnicodeRange:   "UNICODE-RANGE",
+	TokenCDO:            "CDO",
+	TokenCDC:            "CDC",
+	TokenS:              "S",
+	TokenComment:        "COMMENT",
+	TokenFunction:       "FUNCTION",
+	TokenIncludes:       "INCLUDES",
+	TokenDashMatch:      "DASHMATCH",
+	TokenPrefixMatch:    "PREFIXMATCH",
+	TokenSuffixMatch:    "SUFFIXMATCH",
+	TokenSubstringMatch: "SUBSTRINGMATCH",
+	TokenChar:           "CHAR",
+	TokenBOM:            "BOM",
+}
+
+// Macros and productions -----------------------------------------------------
+// http://www.w3.org/TR/css3-syntax/#tokenization
+
+var macroRegexp = regexp.MustCompile(`\{[a-z]+\}`)
+
+// macros maps macro names to patterns to be expanded.
+var macros = map[string]string{
+	// must be escaped: `\.+*?()|[]{}^$`
+	"ident":      `-?{nmstart}{nmchar}*`,
+	"name":       `{nmchar}+`,
+	"nmstart":    `[a-zA-Z_]|{nonascii}|{escape}`,
+	"nonascii":   "[\u0080-\uD7FF\uE000-\uFFFD\U00010000-\U0010FFFF]",
+	"unicode":    `\\[0-9a-fA-F]{1,6}{wc}?`,
+	"escape":     "{unicode}|\\\\[\u0020-\u007E\u0080-\uD7FF\uE000-\uFFFD\U00010000-\U0010FFFF]",
+	"nmchar":     `[a-zA-Z0-9_-]|{nonascii}|{escape}`,
+	"num":        `[0-9]*\.[0-9]+|[0-9]+`,
+	"string":     `"(?:{stringchar}|')*"|'(?:{stringchar}|")*'`,
+	"stringchar": `{urlchar}|[ ]|\\{nl}`,
+	"nl":         `[\n\r\f]|\r\n`,
+	"w":          `{wc}*`,
+	"wc":         `[\t\n\f\r ]`,
+
+	// urlchar should accept [(ascii characters minus those that need escaping)|{nonascii}|{escape}]
+	// ASCII characters range = `[\u0020-\u007e]`
+	// Skip space \u0020 = `[\u0021-\u007e]`
+	// Skip quotation mark \0022 = `[\u0021\u0023-\u007e]`
+	// Skip apostrophe \u0027 = `[\u0021\u0023-\u0026\u0028-\u007e]`
+	// Skip reverse solidus \u005c = `[\u0021\u0023-\u0026\u0028-\u005b\u005d\u007e]`
+	// Finally, the left square bracket (\u005b) and right (\u005d) needs escaping themselves
+	"urlchar": "[\u0021\u0023-\u0026\u0028-\\\u005b\\\u005d-\u007E]|{nonascii}|{escape}",
+}
+
+// productions maps the list of tokens to patterns to be expanded.
+var productions = map[tokenType]string{
+	// Unused regexps (matched using other methods) are commented out.
+	TokenIdent:        `{ident}`,
+	TokenAtKeyword:    `@{ident}`,
+	TokenString:       `{string}`,
+	TokenHash:         `#{name}`,
+	TokenNumber:       `{num}`,
+	TokenPercentage:   `{num}%`,
+	TokenDimension:    `{num}{ident}`,
+	TokenURI:          `url\({w}(?:{string}|{urlchar}*?){w}\)`,
+	TokenUnicodeRange: `U\+[0-9A-F\?]{1,6}(?:-[0-9A-F]{1,6})?`,
+	//TokenCDO:            `<!--`,
+	TokenCDC:      `-->`,
+	TokenS:        `{wc}+`,
+	TokenComment:  `/\*[^\*]*[\*]+(?:[^/][^\*]*[\*]+)*/`,
+	TokenFunction: `{ident}\(`,
+	//TokenIncludes:       `~=`,
+	//TokenDashMatch:      `\|=`,
+	//TokenPrefixMatch:    `\^=`,
+	//TokenSuffixMatch:    `\$=`,
+	//TokenSubstringMatch: `\*=`,
+	//TokenChar:           `[^"']`,
+	//TokenBOM:            "\uFEFF",
+}
+
+// matchers maps the list of tokens to compiled regular expressions.
+//
+// The map is filled on init() using the macros and productions defined in
+// the CSS specification.
+var matchers = map[tokenType]*regexp.Regexp{}
+
+// matchOrder is the order to test regexps when first-char shortcuts
+// can't be used.
+var matchOrder = []tokenType{
+	TokenURI,
+	TokenFunction,
+	TokenUnicodeRange,
+	TokenIdent,
+	TokenDimension,
+	TokenPercentage,
+	TokenNumber,
+	TokenCDC,
+}
+
+func init() {
+	// replace macros and compile regexps for productions.
+	replaceMacro := func(s string) string {
+		return "(?:" + macros[s[1:len(s)-1]] + ")"
+	}
+	for t, s := range productions {
+		for macroRegexp.MatchString(s) {
+			s = macroRegexp.ReplaceAllStringFunc(s, replaceMacro)
+		}
+		matchers[t] = regexp.MustCompile("^(?:" + s + ")")
+	}
+}
+
+// Scanner --------------------------------------------------------------------
+
+// New returns a new CSS scanner for the given input.
+func New(input string) *Scanner {
+	// Normalize newlines.
+	input = strings.Replace(input, "\r\n", "\n", -1)
+	return &Scanner{
+		input: input,
+		row:   1,
+		col:   1,
+	}
+}
+
+// Scanner scans an input and emits tokens following the CSS3 specification.
+type Scanner struct {
+	input string
+	pos   int
+	row   int
+	col   int
+	err   *Token
+}
+
+// Next returns the next token from the input.
+//
+// At the end of the input the token type is TokenEOF.
+//
+// If the input can't be tokenized the token type is TokenError. This occurs
+// in case of unclosed quotation marks or comments.
+func (s *Scanner) Next() *Token {
+	if s.err != nil {
+		return s.err
+	}
+	if s.pos >= len(s.input) {
+		s.err = &Token{TokenEOF, "", s.row, s.col}
+		return s.err
+	}
+	if s.pos == 0 {
+		// Test BOM only once, at the beginning of the file.
+		if strings.HasPrefix(s.input, "\uFEFF") {
+			return s.emitSimple(TokenBOM, "\uFEFF")
+		}
+	}
+	// There's a lot we can guess based on the first byte so we'll take a
+	// shortcut before testing multiple regexps.
+	input := s.input[s.pos:]
+	switch input[0] {
+	case '\t', '\n', '\f', '\r', ' ':
+		// Whitespace.
+		return s.emitToken(TokenS, matchers[TokenS].FindString(input))
+	case '.':
+		// Dot is too common to not have a quick check.
+		// We'll test if this is a Char; if it is followed by a number it is a
+		// dimension/percentage/number, and this will be matched later.
+		if len(input) > 1 && !unicode.IsDigit(rune(input[1])) {
+			return s.emitSimple(TokenChar, ".")
+		}
+	case '#':
+		// Another common one: Hash or Char.
+		if match := matchers[TokenHash].FindString(input); match != "" {
+			return s.emitToken(TokenHash, match)
+		}
+		return s.emitSimple(TokenChar, "#")
+	case '@':
+		// Another common one: AtKeyword or Char.
+		if match := matchers[TokenAtKeyword].FindString(input); match != "" {
+			return s.emitSimple(TokenAtKeyword, match)
+		}
+		return s.emitSimple(TokenChar, "@")
+	case ':', ',', ';', '%', '&', '+', '=', '>', '(', ')', '[', ']', '{', '}':
+		// More common chars.
+		return s.emitSimple(TokenChar, string(input[0]))
+	case '"', '\'':
+		// String or error.
+		match := matchers[TokenString].FindString(input)
+		if match != "" {
+			return s.emitToken(TokenString, match)
+		}
+
+		s.err = &Token{TokenError, "unclosed quotation mark", s.row, s.col}
+		return s.err
+	case '/':
+		// Comment, error or Char.
+		if len(input) > 1 && input[1] == '*' {
+			match := matchers[TokenComment].FindString(input)
+			if match != "" {
+				return s.emitToken(TokenComment, match)
+			} else {
+				s.err = &Token{TokenError, "unclosed comment", s.row, s.col}
+				return s.err
+			}
+		}
+		return s.emitSimple(TokenChar, "/")
+	case '~':
+		// Includes or Char.
+		return s.emitPrefixOrChar(TokenIncludes, "~=")
+	case '|':
+		// DashMatch or Char.
+		return s.emitPrefixOrChar(TokenDashMatch, "|=")
+	case '^':
+		// PrefixMatch or Char.
+		return s.emitPrefixOrChar(TokenPrefixMatch, "^=")
+	case '$':
+		// SuffixMatch or Char.
+		return s.emitPrefixOrChar(TokenSuffixMatch, "$=")
+	case '*':
+		// SubstringMatch or Char.
+		return s.emitPrefixOrChar(TokenSubstringMatch, "*=")
+	case '<':
+		// CDO or Char.
+		return s.emitPrefixOrChar(TokenCDO, "<!--")
+	}
+	// Test all regexps, in order.
+	for _, token := range matchOrder {
+		if match := matchers[token].FindString(input); match != "" {
+			return s.emitToken(token, match)
+		}
+	}
+	// We already handled unclosed quotation marks and comments,
+	// so this can only be a Char.
+	r, width := utf8.DecodeRuneInString(input)
+	token := &Token{TokenChar, string(r), s.row, s.col}
+	s.col += width
+	s.pos += width
+	return token
+}
+
+// updatePosition updates input coordinates based on the consumed text.
+func (s *Scanner) updatePosition(text string) {
+	width := utf8.RuneCountInString(text)
+	lines := strings.Count(text, "\n")
+	s.row += lines
+	if lines == 0 {
+		s.col += width
+	} else {
+		s.col = utf8.RuneCountInString(text[strings.LastIndex(text, "\n"):])
+	}
+	s.pos += len(text) // while col is a rune index, pos is a byte index
+}
+
+// emitToken returns a Token for the string v and updates the scanner position.
+func (s *Scanner) emitToken(t tokenType, v string) *Token {
+	token := &Token{t, v, s.row, s.col}
+	s.updatePosition(v)
+	return token
+}
+
+// emitSimple returns a Token for the string v and updates the scanner
+// position in a simplified manner.
+//
+// The string is known to have only ASCII characters and to not have a newline.
+func (s *Scanner) emitSimple(t tokenType, v string) *Token {
+	token := &Token{t, v, s.row, s.col}
+	s.col += len(v)
+	s.pos += len(v)
+	return token
+}
+
+// emitPrefixOrChar returns a Token for type t if the current position
+// matches the given prefix. Otherwise it returns a Char token using the
+// first character from the prefix.
+//
+// The prefix is known to have only ASCII characters and to not have a newline.
+func (s *Scanner) emitPrefixOrChar(t tokenType, prefix string) *Token {
+	if strings.HasPrefix(s.input[s.pos:], prefix) {
+		return s.emitSimple(t, prefix)
+	}
+	return s.emitSimple(TokenChar, string(prefix[0]))
+}

vendor/github.com/microcosm-cc/bluemonday/.editorconfig

@@ -0,0 +1,4 @@
+root = true
+
+[*]
+end_of_line = lf

vendor/github.com/microcosm-cc/bluemonday/.gitattributes

@@ -0,0 +1 @@
+* text=auto eol=lf

vendor/github.com/microcosm-cc/bluemonday/.gitignore

@@ -0,0 +1,15 @@
+ # Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+# goland idea folder
+*.idea

vendor/github.com/microcosm-cc/bluemonday/.travis.yml

@@ -1,6 +1,5 @@
 language: go
 go:
-  - 1.1.x
   - 1.2.x
   - 1.3.x
   - 1.4.x
@@ -11,6 +10,11 @@ go:
   - 1.9.x
   - 1.10.x
   - 1.11.x
+  - 1.12.x
+  - 1.13.x
+  - 1.14.x
+  - 1.15.x
+  - 1.16.x
   - tip
 matrix:
   allow_failures:

vendor/github.com/microcosm-cc/bluemonday/CONTRIBUTING.md

@@ -9,6 +9,7 @@ Third-party patches are essential for keeping bluemonday secure and offering the
 ## Guidelines
 
 1. Do not vendor dependencies. As a security package, were we to vendor dependencies the projects that then vendor bluemonday may not receive the latest security updates to the dependencies. By not vendoring dependencies the project that implements bluemonday will vendor the latest version of any dependent packages. Vendoring is a project problem, not a package problem. bluemonday will be tested against the latest version of dependencies periodically and during any PR/merge.
+2. I do not care about spelling mistakes or whitespace and I do not believe that you should either. PRs therefore must be functional in their nature or be substantial and impactful if documentation or examples.
 
 ## Submitting an Issue
 

vendor/github.com/microcosm-cc/bluemonday/CREDITS.md

@@ -1,6 +1,8 @@
-1. Andrew Krasichkov @buglloc https://github.com/buglloc
 1. John Graham-Cumming http://jgc.org/
+1. Mohammad Gufran https://github.com/Gufran
+1. Steven Gutzwiller https://github.com/StevenGutzwiller
+1. Andrew Krasichkov @buglloc https://github.com/buglloc
 1. Mike Samuel mikesamuel@gmail.com
 1. Dmitri Shuralyov shurcooL@gmail.com
-1. https://github.com/opennota
-1. https://github.com/Gufran
+1. opennota https://github.com/opennota https://gitlab.com/opennota
+1. Tom Anthony https://www.tomanthony.co.uk/

vendor/github.com/microcosm-cc/bluemonday/Makefile

@@ -3,6 +3,7 @@
 #   all:          Builds the code locally after testing
 #
 #   fmt:          Formats the source files
+#   fmt-check:    Check if the source files are formated
 #   build:        Builds the code locally
 #   vet:          Vets the code
 #   lint:         Runs lint over the code (you do not need to fix everything)
@@ -11,6 +12,8 @@
 #
 #   install:      Builds, tests and installs the code locally
 
+GOFILES_NOVENDOR = $(shell find . -type f -name '*.go' -not -path "./vendor/*" -not -path "./.git/*")
+
 .PHONY: all fmt build vet lint test cover install
 
 # The first target is always the default action if `make` is called without
@@ -19,13 +22,16 @@
 all: fmt vet test install
 
 fmt:
-	@gofmt -s -w ./$*
+	@gofmt -s -w ${GOFILES_NOVENDOR}
+
+fmt-check:
+	@([ -z "$(shell gofmt -d $(GOFILES_NOVENDOR) | head)" ]) || (echo "Source is unformatted"; exit 1)
 
 build:
 	@go build
 
 vet:
-	@go vet *.go
+	@go vet
 
 lint:
 	@golint *.go

vendor/github.com/microcosm-cc/bluemonday/README.md

@@ -2,7 +2,7 @@
 
 bluemonday is a HTML sanitizer implemented in Go. It is fast and highly configurable.
 
-bluemonday takes untrusted user generated content as an input, and will return HTML that has been sanitised against a whitelist of approved HTML elements and attributes so that you can safely include the content in your web page.
+bluemonday takes untrusted user generated content as an input, and will return HTML that has been sanitised against an allowlist of approved HTML elements and attributes so that you can safely include the content in your web page.
 
 If you accept user generated content, and your server uses Go, you **need** bluemonday.
 
@@ -50,18 +50,20 @@ bluemonday is heavily inspired by both the [OWASP Java HTML Sanitizer](https://c
 
 ## Technical Summary
 
-Whitelist based, you need to either build a policy describing the HTML elements and attributes to permit (and the `regexp` patterns of attributes), or use one of the supplied policies representing good defaults.
+Allowlist based, you need to either build a policy describing the HTML elements and attributes to permit (and the `regexp` patterns of attributes), or use one of the supplied policies representing good defaults.
 
-The policy containing the whitelist is applied using a fast non-validating, forward only, token-based parser implemented in the [Go net/html library](https://godoc.org/golang.org/x/net/html) by the core Go team.
+The policy containing the allowlist is applied using a fast non-validating, forward only, token-based parser implemented in the [Go net/html library](https://godoc.org/golang.org/x/net/html) by the core Go team.
 
-We expect to be supplied with well-formatted HTML (closing elements for every applicable open element, nested correctly) and so we do not focus on repairing badly nested or incomplete HTML. We focus on simply ensuring that whatever elements do exist are described in the policy whitelist and that attributes and links are safe for use on your web page. [GIGO](http://en.wikipedia.org/wiki/Garbage_in,_garbage_out) does apply and if you feed it bad HTML bluemonday is not tasked with figuring out how to make it good again.
+We expect to be supplied with well-formatted HTML (closing elements for every applicable open element, nested correctly) and so we do not focus on repairing badly nested or incomplete HTML. We focus on simply ensuring that whatever elements do exist are described in the policy allowlist and that attributes and links are safe for use on your web page. [GIGO](http://en.wikipedia.org/wiki/Garbage_in,_garbage_out) does apply and if you feed it bad HTML bluemonday is not tasked with figuring out how to make it good again.
 
 ### Supported Go Versions
 
-bluemonday is tested against Go 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and tip.
+bluemonday is tested on all versions since Go 1.2 including tip.
 
 We do not support Go 1.0 as we depend on `golang.org/x/net/html` which includes a reference to `io.ErrNoProgress` which did not exist in Go 1.0.
 
+We support Go 1.1 but Travis no longer tests against it.
+
 ## Is it production ready?
 
 *Yes*
@@ -90,7 +92,7 @@ func main() {
 	// Do this once for each unique policy, and use the policy for the life of the program
 	// Policy creation/editing is not safe to use in multiple goroutines
 	p := bluemonday.UGCPolicy()
-	
+
 	// The policy can then be used to sanitize lots of input and it is safe to use the policy in multiple goroutines
 	html := p.Sanitize(
 		`<a onblur="alert(secret)" href="http://www.google.com">Google</a>`,
@@ -144,8 +146,8 @@ func main() {
 
 We ship two default policies:
 
-1. `bluemonday.StrictPolicy()` which can be thought of as equivalent to stripping all HTML elements and their attributes as it has nothing on its whitelist. An example usage scenario would be blog post titles where HTML tags are not expected at all and if they are then the elements *and* the content of the elements should be stripped. This is a *very* strict policy.
-2. `bluemonday.UGCPolicy()` which allows a broad selection of HTML elements and attributes that are safe for user generated content. Note that this policy does *not* whitelist iframes, object, embed, styles, script, etc. An example usage scenario would be blog post bodies where a variety of formatting is expected along with the potential for TABLEs and IMGs.
+1. `bluemonday.StrictPolicy()` which can be thought of as equivalent to stripping all HTML elements and their attributes as it has nothing on its allowlist. An example usage scenario would be blog post titles where HTML tags are not expected at all and if they are then the elements *and* the content of the elements should be stripped. This is a *very* strict policy.
+2. `bluemonday.UGCPolicy()` which allows a broad selection of HTML elements and attributes that are safe for user generated content. Note that this policy does *not* allow iframes, object, embed, styles, script, etc. An example usage scenario would be blog post bodies where a variety of formatting is expected along with the potential for TABLEs and IMGs.
 
 ## Policy Building
 
@@ -167,12 +169,26 @@ To add elements to a policy either add just the elements:
 p.AllowElements("b", "strong")
 ```
 
+Or using a regex:
+
+_Note: if an element is added by name as shown above, any matching regex will be ignored_
+
+It is also recommended to ensure multiple patterns don't overlap as order of execution is not guaranteed and can result in some rules being missed.
+```go
+p.AllowElementsMatching(regex.MustCompile(`^my-element-`))
+```
+
 Or add elements as a virtue of adding an attribute:
 ```go
-// Not the recommended pattern, see the recommendation on using .Matching() below
+// Note the recommended pattern, see the recommendation on using .Matching() below
 p.AllowAttrs("nowrap").OnElements("td", "th")
 ```
 
+Again, this also supports a regex pattern match alternative:
+```go
+p.AllowAttrs("nowrap").OnElementsMatching(regex.MustCompile(`^my-element-`))
+```
+
 Attributes can either be added to all elements:
 ```go
 p.AllowAttrs("dir").Matching(regexp.MustCompile("(?i)rtl|ltr")).Globally()
@@ -202,6 +218,50 @@ p := bluemonday.UGCPolicy()
 p.AllowElements("fieldset", "select", "option")
 ```
 
+### Inline CSS
+
+Although it's possible to handle inline CSS using `AllowAttrs` with a `Matching` rule, writing a single monolithic regular expression to safely process all inline CSS which you wish to allow is not a trivial task.  Instead of attempting to do so, you can allow the `style` attribute on whichever element(s) you desire and use style policies to control and sanitize inline styles.
+
+It is strongly recommended that you use `Matching` (with a suitable regular expression)
+`MatchingEnum`, or `MatchingHandler` to ensure each style matches your needs,
+but default handlers are supplied for most widely used styles.
+
+Similar to attributes, you can allow specific CSS properties to be set inline:
+```go
+p.AllowAttrs("style").OnElements("span", "p")
+// Allow the 'color' property with valid RGB(A) hex values only (on any element allowed a 'style' attribute)
+p.AllowStyles("color").Matching(regexp.MustCompile("(?i)^#([0-9a-f]{3,4}|[0-9a-f]{6}|[0-9a-f]{8})$")).Globally()
+```
+
+Additionally, you can allow a CSS property to be set only to an allowed value:
+```go
+p.AllowAttrs("style").OnElements("span", "p")
+// Allow the 'text-decoration' property to be set to 'underline', 'line-through' or 'none'
+// on 'span' elements only
+p.AllowStyles("text-decoration").MatchingEnum("underline", "line-through", "none").OnElements("span")
+```
+
+Or you can specify elements based on a regex pattern match:
+```go
+p.AllowAttrs("style").OnElementsMatching(regex.MustCompile(`^my-element-`))
+// Allow the 'text-decoration' property to be set to 'underline', 'line-through' or 'none'
+// on 'span' elements only
+p.AllowStyles("text-decoration").MatchingEnum("underline", "line-through", "none").OnElementsMatching(regex.MustCompile(`^my-element-`))
+```
+
+If you need more specific checking, you can create a handler that takes in a string and returns a bool to
+validate the values for a given property. The string parameter has been
+converted to lowercase and unicode code points have been converted.
+```go
+myHandler := func(value string) bool{
+	// Validate your input here
+	return true
+}
+p.AllowAttrs("style").OnElements("span", "p")
+// Allow the 'color' property with values validated by the handler (on any element allowed a 'style' attribute)
+p.AllowStyles("color").MatchingHandler(myHandler).Globally()
+```
+
 ### Links
 
 Links are difficult beasts to sanitise safely and also one of the biggest attack vectors for malicious content.
@@ -220,12 +280,12 @@ We provide some additional global options for safely working with links.
 p.RequireParseableURLs(true)
 ```
 
-If you have enabled parseable URLs then the following option will `AllowRelativeURLs`. By default this is disabled (bluemonday is a whitelist tool... you need to explicitly tell us to permit things) and when disabled it will prevent all local and scheme relative URLs (i.e. `href="localpage.html"`, `href="../home.html"` and even `href="//www.google.com"` are relative):
+If you have enabled parseable URLs then the following option will `AllowRelativeURLs`. By default this is disabled (bluemonday is an allowlist tool... you need to explicitly tell us to permit things) and when disabled it will prevent all local and scheme relative URLs (i.e. `href="localpage.html"`, `href="../home.html"` and even `href="//www.google.com"` are relative):
 ```go
 p.AllowRelativeURLs(true)
 ```
 
-If you have enabled parseable URLs then you can whitelist the schemes (commonly called protocol when thinking of `http` and `https`) that are permitted. Bear in mind that allowing relative URLs in the above option will allow for a blank scheme:
+If you have enabled parseable URLs then you can allow the schemes (commonly called protocol when thinking of `http` and `https`) that are permitted. Bear in mind that allowing relative URLs in the above option will allow for a blank scheme:
 ```go
 p.AllowURLSchemes("mailto", "http", "https")
 ```
@@ -236,7 +296,14 @@ Regardless of whether you have enabled parseable URLs, you can force all URLs to
 p.RequireNoFollowOnLinks(true)
 ```
 
-We provide a convenience method that applies all of the above, but you will still need to whitelist the linkable elements for the URL rules to be applied to:
+Similarly, you can force all URLs to have "noreferrer" in their rel attribute.
+```go
+// This applies to "a" "area" "link" elements that have a "href" attribute
+p.RequireNoReferrerOnLinks(true)
+```
+
+
+We provide a convenience method that applies all of the above, but you will still need to allow the linkable elements for the URL rules to be applied to:
 ```go
 p.AllowStandardURLs()
 p.AllowAttrs("cite").OnElements("blockquote", "q")
@@ -306,17 +373,18 @@ p.AllowAttrs(
 )
 ```
 
-Both examples exhibit the same issue, they declare attributes but do not then specify whether they are whitelisted globally or only on specific elements (and which elements). Attributes belong to one or more elements, and the policy needs to declare this.
+Both examples exhibit the same issue, they declare attributes but do not then specify whether they are allowed globally or only on specific elements (and which elements). Attributes belong to one or more elements, and the policy needs to declare this.
 
 ## Limitations
 
-We are not yet including any tools to help whitelist and sanitize CSS. Which means that unless you wish to do the heavy lifting in a single regular expression (inadvisable), **you should not allow the "style" attribute anywhere**.
+We are not yet including any tools to help allow and sanitize CSS. Which means that unless you wish to do the heavy lifting in a single regular expression (inadvisable), **you should not allow the "style" attribute anywhere**.
+
+In the same theme, both `<script>` and `<style>` are considered harmful. These elements (and their content) will not be rendered by default, and require you to explicitly set `p.AllowUnsafe(true)`. You should be aware that allowing these elements defeats the purpose of using a HTML sanitizer as you would be explicitly allowing either JavaScript (and any plainly written XSS) and CSS (which can modify a DOM to insert JS), and additionally but limitations in this library mean it is not aware of whether HTML is validly structured and that can allow these elements to bypass some of the safety mechanisms built into the [WhatWG HTML parser standard](https://html.spec.whatwg.org/multipage/parsing.html#parsing-main-inselect).
 
 It is not the job of bluemonday to fix your bad HTML, it is merely the job of bluemonday to prevent malicious HTML getting through. If you have mismatched HTML elements, or non-conforming nesting of elements, those will remain. But if you have well-structured HTML bluemonday will not break it.
 
 ## TODO
 
-* Add support for CSS sanitisation to allow some CSS properties based on a whitelist, possibly using the [Gorilla CSS3 scanner](http://www.gorillatoolkit.org/pkg/css/scanner) - PRs welcome so long as testing covers XSS and demonstrates safety first
 * Investigate whether devs want to blacklist elements and attributes. This would allow devs to take an existing policy (such as the `bluemonday.UGCPolicy()` ) that encapsulates 90% of what they're looking for but does more than they need, and to remove the extra things they do not want to make it 100% what they want
 * Investigate whether devs want a validating HTML mode, in which the HTML elements are not just transformed into a balanced tree (every start tag has a closing tag at the correct depth) but also that elements and character data appear only in their allowed context (i.e. that a `table` element isn't a descendent of a `caption`, that `colgroup`, `thead`, `tbody`, `tfoot` and `tr` are permitted, and that character data is not permitted)
 

vendor/github.com/microcosm-cc/bluemonday/SECURITY.md

@@ -0,0 +1,15 @@
+# Security Policy
+
+## Supported Versions
+
+Latest tag and tip are supported.
+
+Older tags remain present but changes result in new tags and are not back ported... please verify any issue against the latest tag and tip.
+
+## Reporting a Vulnerability
+
+Email: <bluemonday@buro9.com>
+
+Bluemonday is pure OSS and not maintained by a company. As such there is no bug bounty program but security issues will be taken seriously and resolved as soon as possible.
+
+The maintainer lives in the United Kingdom and whilst the email is monitored expect a reply or ACK when the maintainer is awake.

vendor/github.com/microcosm-cc/bluemonday/doc.go

@@ -28,10 +28,10 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 /*
-Package bluemonday provides a way of describing a whitelist of HTML elements
+Package bluemonday provides a way of describing an allowlist of HTML elements
 and attributes as a policy, and for that policy to be applied to untrusted
 strings from users that may contain markup. All elements and attributes not on
-the whitelist will be stripped.
+the allowlist will be stripped.
 
 The default bluemonday.UGCPolicy().Sanitize() turns this:
 
@@ -84,21 +84,21 @@ bluemonday is heavily inspired by both the OWASP Java HTML Sanitizer
 
 We ship two default policies, one is bluemonday.StrictPolicy() and can be
 thought of as equivalent to stripping all HTML elements and their attributes as
-it has nothing on its whitelist.
+it has nothing on its allowlist.
 
 The other is bluemonday.UGCPolicy() and allows a broad selection of HTML
 elements and attributes that are safe for user generated content. Note that
-this policy does not whitelist iframes, object, embed, styles, script, etc.
+this policy does not allow iframes, object, embed, styles, script, etc.
 
 The essence of building a policy is to determine which HTML elements and
 attributes are considered safe for your scenario. OWASP provide an XSS
 prevention cheat sheet ( https://www.google.com/search?q=xss+prevention+cheat+sheet )
 to help explain the risks, but essentially:
 
-    1. Avoid whitelisting anything other than plain HTML elements
-    2. Avoid whitelisting `script`, `style`, `iframe`, `object`, `embed`, `base`
+    1. Avoid allowing anything other than plain HTML elements
+    2. Avoid allowing `script`, `style`, `iframe`, `object`, `embed`, `base`
        elements
-    3. Avoid whitelisting anything other than plain HTML elements with simple
+    3. Avoid allowing anything other than plain HTML elements with simple
        values that you can match to a regexp
 */
 package bluemonday

vendor/github.com/microcosm-cc/bluemonday/helpers.go

@@ -135,13 +135,13 @@ func (p *Policy) AllowStandardURLs() {
 	// Most common URL schemes only
 	p.AllowURLSchemes("mailto", "http", "https")
 
-	// For all anchors we will add rel="nofollow" if it does not already exist
+	// For linking elements we will add rel="nofollow" if it does not already exist
 	// This applies to "a" "area" "link"
 	p.RequireNoFollowOnLinks(true)
 }
 
 // AllowStandardAttributes will enable "id", "title" and the language specific
-// attributes "dir" and "lang" on all elements that are whitelisted
+// attributes "dir" and "lang" on all elements that are allowed
 func (p *Policy) AllowStandardAttributes() {
 	// "dir" "lang" are permitted as both language attributes affect charsets
 	// and direction of text.
@@ -295,3 +295,9 @@ func (p *Policy) AllowTables() {
 		CellVerticalAlign,
 	).OnElements("tbody", "tfoot")
 }
+
+func (p *Policy) AllowIFrames(vals ...SandboxValue) {
+	p.AllowAttrs("sandbox").OnElements("iframe")
+
+	p.RequireSandboxOnIFrame(vals...)
+}

vendor/github.com/microcosm-cc/bluemonday/policy.go

@@ -29,13 +29,17 @@
 
 package bluemonday
 
+//TODO sgutzwiller create map of styles to default handlers
+//TODO sgutzwiller create handlers for various attributes
 import (
 	"net/url"
 	"regexp"
 	"strings"
+
+	"github.com/microcosm-cc/bluemonday/css"
 )
 
-// Policy encapsulates the whitelist of HTML elements and attributes that will
+// Policy encapsulates the allowlist of HTML elements and attributes that will
 // be applied to the sanitised HTML.
 //
 // You should use bluemonday.NewPolicy() to create a blank policy as the
@@ -51,14 +55,28 @@ type Policy struct {
 	// tag is replaced by a space character.
 	addSpaces bool
 
-	// When true, add rel="nofollow" to HTML anchors
+	// When true, add rel="nofollow" to HTML a, area, and link tags
 	requireNoFollow bool
 
-	// When true, add rel="nofollow" to HTML anchors
+	// When true, add rel="nofollow" to HTML a, area, and link tags
 	// Will add for href="http://foo"
 	// Will skip for href="/foo" or href="foo"
 	requireNoFollowFullyQualifiedLinks bool
 
+	// When true, add rel="noreferrer" to HTML a, area, and link tags
+	requireNoReferrer bool
+
+	// When true, add rel="noreferrer" to HTML a, area, and link tags
+	// Will add for href="http://foo"
+	// Will skip for href="/foo" or href="foo"
+	requireNoReferrerFullyQualifiedLinks bool
+
+	// When true, add crossorigin="anonymous" to HTML audio, img, link, script, and video tags
+	requireCrossOriginAnonymous bool
+
+	// When true, add and filter sandbox attribute on iframe tags
+	requireSandboxOnIFrame map[string]bool
+
 	// When true add target="_blank" to fully qualified links
 	// Will add for href="http://foo"
 	// Will skip for href="/foo" or href="foo"
@@ -73,16 +91,31 @@ type Policy struct {
 	// When true, allow data attributes.
 	allowDataAttributes bool
 
-	// map[htmlElementName]map[htmlAttributeName]attrPolicy
-	elsAndAttrs map[string]map[string]attrPolicy
+	// When true, allow comments.
+	allowComments bool
 
-	// map[htmlAttributeName]attrPolicy
-	globalAttrs map[string]attrPolicy
+	// map[htmlElementName]map[htmlAttributeName][]attrPolicy
+	elsAndAttrs map[string]map[string][]attrPolicy
+
+	// elsMatchingAndAttrs stores regex based element matches along with attributes
+	elsMatchingAndAttrs map[*regexp.Regexp]map[string][]attrPolicy
+
+	// map[htmlAttributeName][]attrPolicy
+	globalAttrs map[string][]attrPolicy
+
+	// map[htmlElementName]map[cssPropertyName][]stylePolicy
+	elsAndStyles map[string]map[string][]stylePolicy
+
+	// map[regex]map[cssPropertyName][]stylePolicy
+	elsMatchingAndStyles map[*regexp.Regexp]map[string][]stylePolicy
+
+	// map[cssPropertyName][]stylePolicy
+	globalStyles map[string][]stylePolicy
 
 	// If urlPolicy is nil, all URLs with matching schema are allowed.
 	// Otherwise, only the URLs with matching schema and urlPolicy(url)
 	// returning true are allowed.
-	allowURLSchemes map[string]urlPolicy
+	allowURLSchemes map[string][]urlPolicy
 
 	// If an element has had all attributes removed as a result of a policy
 	// being applied, then the element would be removed from the output.
@@ -93,7 +126,30 @@ type Policy struct {
 	// be maintained in the output HTML.
 	setOfElementsAllowedWithoutAttrs map[string]struct{}
 
+	// If an element has had all attributes removed as a result of a policy
+	// being applied, then the element would be removed from the output.
+	//
+	// However some elements are valid and have strong layout meaning without
+	// any attributes, i.e. <table>.
+	//
+	// In this case, any element matching a regular expression will be accepted without
+	// attributes added.
+	setOfElementsMatchingAllowedWithoutAttrs []*regexp.Regexp
+
 	setOfElementsToSkipContent map[string]struct{}
+
+	// Permits fundamentally unsafe elements.
+	//
+	// If false (default) then elements such as `style` and `script` will not be
+	// permitted even if declared in a policy. These elements when combined with
+	// untrusted input cannot be safely handled by bluemonday at this point in
+	// time.
+	//
+	// If true then `style` and `script` would be permitted by bluemonday if a
+	// policy declares them. However this is not recommended under any circumstance
+	// and can lead to XSS being rendered thus defeating the purpose of using a
+	// HTML sanitizer.
+	allowUnsafe bool
 }
 
 type attrPolicy struct {
@@ -103,6 +159,20 @@ type attrPolicy struct {
 	regexp *regexp.Regexp
 }
 
+type stylePolicy struct {
+	// handler to validate
+	handler func(string) bool
+
+	// optional pattern to match, when not nil the regexp needs to match
+	// otherwise the property is removed
+	regexp *regexp.Regexp
+
+	// optional list of allowed property values, for properties which
+	// have a defined list of allowed values; property will be removed
+	// if the value is not allowed
+	enum []string
+}
+
 type attrPolicyBuilder struct {
 	p *Policy
 
@@ -111,23 +181,55 @@ type attrPolicyBuilder struct {
 	allowEmpty bool
 }
 
+type stylePolicyBuilder struct {
+	p *Policy
+
+	propertyNames []string
+	regexp        *regexp.Regexp
+	enum          []string
+	handler       func(string) bool
+}
+
 type urlPolicy func(url *url.URL) (allowUrl bool)
 
+type SandboxValue int64
+
+const (
+	SandboxAllowDownloads SandboxValue = iota
+	SandboxAllowDownloadsWithoutUserActivation
+	SandboxAllowForms
+	SandboxAllowModals
+	SandboxAllowOrientationLock
+	SandboxAllowPointerLock
+	SandboxAllowPopups
+	SandboxAllowPopupsToEscapeSandbox
+	SandboxAllowPresentation
+	SandboxAllowSameOrigin
+	SandboxAllowScripts
+	SandboxAllowStorageAccessByUserActivation
+	SandboxAllowTopNavigation
+	SandboxAllowTopNavigationByUserActivation
+)
+
 // init initializes the maps if this has not been done already
 func (p *Policy) init() {
 	if !p.initialized {
-		p.elsAndAttrs = make(map[string]map[string]attrPolicy)
-		p.globalAttrs = make(map[string]attrPolicy)
-		p.allowURLSchemes = make(map[string]urlPolicy)
+		p.elsAndAttrs = make(map[string]map[string][]attrPolicy)
+		p.elsMatchingAndAttrs = make(map[*regexp.Regexp]map[string][]attrPolicy)
+		p.globalAttrs = make(map[string][]attrPolicy)
+		p.elsAndStyles = make(map[string]map[string][]stylePolicy)
+		p.elsMatchingAndStyles = make(map[*regexp.Regexp]map[string][]stylePolicy)
+		p.globalStyles = make(map[string][]stylePolicy)
+		p.allowURLSchemes = make(map[string][]urlPolicy)
 		p.setOfElementsAllowedWithoutAttrs = make(map[string]struct{})
 		p.setOfElementsToSkipContent = make(map[string]struct{})
 		p.initialized = true
 	}
 }
 
-// NewPolicy returns a blank policy with nothing whitelisted or permitted. This
+// NewPolicy returns a blank policy with nothing allowed or permitted. This
 // is the recommended way to start building a policy and you should now use
-// AllowAttrs() and/or AllowElements() to construct the whitelist of HTML
+// AllowAttrs() and/or AllowElements() to construct the allowlist of HTML
 // elements and attributes.
 func NewPolicy() *Policy {
 
@@ -141,7 +243,7 @@ func NewPolicy() *Policy {
 
 // AllowAttrs takes a range of HTML attribute names and returns an
 // attribute policy builder that allows you to specify the pattern and scope of
-// the whitelisted attribute.
+// the allowed attribute.
 //
 // The attribute policy is only added to the core policy when either Globally()
 // or OnElements(...) are called.
@@ -161,7 +263,7 @@ func (p *Policy) AllowAttrs(attrNames ...string) *attrPolicyBuilder {
 	return &abp
 }
 
-// AllowDataAttributes whitelists all data attributes. We can't specify the name
+// AllowDataAttributes permits all data attributes. We can't specify the name
 // of each attribute exactly as they are customized.
 //
 // NOTE: These values are not sanitized and applications that evaluate or process
@@ -176,6 +278,22 @@ func (p *Policy) AllowDataAttributes() {
 	p.allowDataAttributes = true
 }
 
+// AllowComments allows comments.
+//
+// Please note that only one type of comment will be allowed by this, this is the
+// the standard HTML comment <!-- --> which includes the use of that to permit
+// conditionals as per https://docs.microsoft.com/en-us/previous-versions/windows/internet-explorer/ie-developer/compatibility/ms537512(v=vs.85)?redirectedfrom=MSDN
+//
+// What is not permitted are CDATA XML comments, as the x/net/html package we depend
+// on does not handle this fully and we are not choosing to take on that work:
+// https://pkg.go.dev/golang.org/x/net/html#Tokenizer.AllowCDATA . If the x/net/html
+// package changes this then these will be considered, otherwise if you AllowComments
+// but provide a CDATA comment, then as per the documentation in x/net/html this will
+// be treated as a plain HTML comment.
+func (p *Policy) AllowComments() {
+	p.allowComments = true
+}
+
 // AllowNoAttrs says that attributes on element are optional.
 //
 // The attribute policy is only added to the core policy when OnElements(...)
@@ -203,8 +321,7 @@ func (abp *attrPolicyBuilder) AllowNoAttrs() *attrPolicyBuilder {
 }
 
 // Matching allows a regular expression to be applied to a nascent attribute
-// policy, and returns the attribute policy. Calling this more than once will
-// replace the existing regexp.
+// policy, and returns the attribute policy.
 func (abp *attrPolicyBuilder) Matching(regex *regexp.Regexp) *attrPolicyBuilder {
 
 	abp.regexp = regex
@@ -222,7 +339,7 @@ func (abp *attrPolicyBuilder) OnElements(elements ...string) *Policy {
 		for _, attr := range abp.attrNames {
 
 			if _, ok := abp.p.elsAndAttrs[element]; !ok {
-				abp.p.elsAndAttrs[element] = make(map[string]attrPolicy)
+				abp.p.elsAndAttrs[element] = make(map[string][]attrPolicy)
 			}
 
 			ap := attrPolicy{}
@@ -230,14 +347,14 @@ func (abp *attrPolicyBuilder) OnElements(elements ...string) *Policy {
 				ap.regexp = abp.regexp
 			}
 
-			abp.p.elsAndAttrs[element][attr] = ap
+			abp.p.elsAndAttrs[element][attr] = append(abp.p.elsAndAttrs[element][attr], ap)
 		}
 
 		if abp.allowEmpty {
 			abp.p.setOfElementsAllowedWithoutAttrs[element] = struct{}{}
 
 			if _, ok := abp.p.elsAndAttrs[element]; !ok {
-				abp.p.elsAndAttrs[element] = make(map[string]attrPolicy)
+				abp.p.elsAndAttrs[element] = make(map[string][]attrPolicy)
 			}
 		}
 	}
@@ -245,13 +362,37 @@ func (abp *attrPolicyBuilder) OnElements(elements ...string) *Policy {
 	return abp.p
 }
 
+// OnElementsMatching will bind an attribute policy to all elements matching a given regex
+// and return the updated policy
+func (abp *attrPolicyBuilder) OnElementsMatching(regex *regexp.Regexp) *Policy {
+	for _, attr := range abp.attrNames {
+		if _, ok := abp.p.elsMatchingAndAttrs[regex]; !ok {
+			abp.p.elsMatchingAndAttrs[regex] = make(map[string][]attrPolicy)
+		}
+		ap := attrPolicy{}
+		if abp.regexp != nil {
+			ap.regexp = abp.regexp
+		}
+		abp.p.elsMatchingAndAttrs[regex][attr] = append(abp.p.elsMatchingAndAttrs[regex][attr], ap)
+	}
+
+	if abp.allowEmpty {
+		abp.p.setOfElementsMatchingAllowedWithoutAttrs = append(abp.p.setOfElementsMatchingAllowedWithoutAttrs, regex)
+		if _, ok := abp.p.elsMatchingAndAttrs[regex]; !ok {
+			abp.p.elsMatchingAndAttrs[regex] = make(map[string][]attrPolicy)
+		}
+	}
+
+	return abp.p
+}
+
 // Globally will bind an attribute policy to all HTML elements and return the
 // updated policy
 func (abp *attrPolicyBuilder) Globally() *Policy {
 
 	for _, attr := range abp.attrNames {
 		if _, ok := abp.p.globalAttrs[attr]; !ok {
-			abp.p.globalAttrs[attr] = attrPolicy{}
+			abp.p.globalAttrs[attr] = []attrPolicy{}
 		}
 
 		ap := attrPolicy{}
@@ -259,13 +400,143 @@ func (abp *attrPolicyBuilder) Globally() *Policy {
 			ap.regexp = abp.regexp
 		}
 
-		abp.p.globalAttrs[attr] = ap
+		abp.p.globalAttrs[attr] = append(abp.p.globalAttrs[attr], ap)
 	}
 
 	return abp.p
 }
 
-// AllowElements will append HTML elements to the whitelist without applying an
+// AllowStyles takes a range of CSS property names and returns a
+// style policy builder that allows you to specify the pattern and scope of
+// the allowed property.
+//
+// The style policy is only added to the core policy when either Globally()
+// or OnElements(...) are called.
+func (p *Policy) AllowStyles(propertyNames ...string) *stylePolicyBuilder {
+
+	p.init()
+
+	abp := stylePolicyBuilder{
+		p: p,
+	}
+
+	for _, propertyName := range propertyNames {
+		abp.propertyNames = append(abp.propertyNames, strings.ToLower(propertyName))
+	}
+
+	return &abp
+}
+
+// Matching allows a regular expression to be applied to a nascent style
+// policy, and returns the style policy.
+func (spb *stylePolicyBuilder) Matching(regex *regexp.Regexp) *stylePolicyBuilder {
+
+	spb.regexp = regex
+
+	return spb
+}
+
+// MatchingEnum allows a list of allowed values to be applied to a nascent style
+// policy, and returns the style policy.
+func (spb *stylePolicyBuilder) MatchingEnum(enum ...string) *stylePolicyBuilder {
+
+	spb.enum = enum
+
+	return spb
+}
+
+// MatchingHandler allows a handler to be applied to a nascent style
+// policy, and returns the style policy.
+func (spb *stylePolicyBuilder) MatchingHandler(handler func(string) bool) *stylePolicyBuilder {
+
+	spb.handler = handler
+
+	return spb
+}
+
+// OnElements will bind a style policy to a given range of HTML elements
+// and return the updated policy
+func (spb *stylePolicyBuilder) OnElements(elements ...string) *Policy {
+
+	for _, element := range elements {
+		element = strings.ToLower(element)
+
+		for _, attr := range spb.propertyNames {
+
+			if _, ok := spb.p.elsAndStyles[element]; !ok {
+				spb.p.elsAndStyles[element] = make(map[string][]stylePolicy)
+			}
+
+			sp := stylePolicy{}
+			if spb.handler != nil {
+				sp.handler = spb.handler
+			} else if len(spb.enum) > 0 {
+				sp.enum = spb.enum
+			} else if spb.regexp != nil {
+				sp.regexp = spb.regexp
+			} else {
+				sp.handler = css.GetDefaultHandler(attr)
+			}
+			spb.p.elsAndStyles[element][attr] = append(spb.p.elsAndStyles[element][attr], sp)
+		}
+	}
+
+	return spb.p
+}
+
+// OnElementsMatching will bind a style policy to any HTML elements matching the pattern
+// and return the updated policy
+func (spb *stylePolicyBuilder) OnElementsMatching(regex *regexp.Regexp) *Policy {
+
+	for _, attr := range spb.propertyNames {
+
+		if _, ok := spb.p.elsMatchingAndStyles[regex]; !ok {
+			spb.p.elsMatchingAndStyles[regex] = make(map[string][]stylePolicy)
+		}
+
+		sp := stylePolicy{}
+		if spb.handler != nil {
+			sp.handler = spb.handler
+		} else if len(spb.enum) > 0 {
+			sp.enum = spb.enum
+		} else if spb.regexp != nil {
+			sp.regexp = spb.regexp
+		} else {
+			sp.handler = css.GetDefaultHandler(attr)
+		}
+		spb.p.elsMatchingAndStyles[regex][attr] = append(spb.p.elsMatchingAndStyles[regex][attr], sp)
+	}
+
+	return spb.p
+}
+
+// Globally will bind a style policy to all HTML elements and return the
+// updated policy
+func (spb *stylePolicyBuilder) Globally() *Policy {
+
+	for _, attr := range spb.propertyNames {
+		if _, ok := spb.p.globalStyles[attr]; !ok {
+			spb.p.globalStyles[attr] = []stylePolicy{}
+		}
+
+		// Use only one strategy for validating styles, fallback to default
+		sp := stylePolicy{}
+		if spb.handler != nil {
+			sp.handler = spb.handler
+		} else if len(spb.enum) > 0 {
+			sp.enum = spb.enum
+		} else if spb.regexp != nil {
+			sp.regexp = spb.regexp
+		} else {
+			sp.handler = css.GetDefaultHandler(attr)
+		}
+		spb.p.globalStyles[attr] = append(spb.p.globalStyles[attr], sp)
+	}
+
+	return spb.p
+}
+
+// AllowElements will append HTML elements to the allowlist without applying an
 // attribute policy to those elements (the elements are permitted
 // sans-attributes)
 func (p *Policy) AllowElements(names ...string) *Policy {
@@ -275,15 +546,25 @@ func (p *Policy) AllowElements(names ...string) *Policy {
 		element = strings.ToLower(element)
 
 		if _, ok := p.elsAndAttrs[element]; !ok {
-			p.elsAndAttrs[element] = make(map[string]attrPolicy)
+			p.elsAndAttrs[element] = make(map[string][]attrPolicy)
 		}
 	}
 
 	return p
 }
 
-// RequireNoFollowOnLinks will result in all <a> tags having a rel="nofollow"
-// added to them if one does not already exist
+// AllowElementsMatching will append HTML elements to the allowlist if they
+// match a regexp.
+func (p *Policy) AllowElementsMatching(regex *regexp.Regexp) *Policy {
+	p.init()
+	if _, ok := p.elsMatchingAndAttrs[regex]; !ok {
+		p.elsMatchingAndAttrs[regex] = make(map[string][]attrPolicy)
+	}
+	return p
+}
+
+// RequireNoFollowOnLinks will result in all a, area, link tags having a
+// rel="nofollow"added to them if one does not already exist
 //
 // Note: This requires p.RequireParseableURLs(true) and will enable it.
 func (p *Policy) RequireNoFollowOnLinks(require bool) *Policy {
@@ -294,9 +575,10 @@ func (p *Policy) RequireNoFollowOnLinks(require bool) *Policy {
 	return p
 }
 
-// RequireNoFollowOnFullyQualifiedLinks will result in all <a> tags that point
-// to a non-local destination (i.e. starts with a protocol and has a host)
-// having a rel="nofollow" added to them if one does not already exist
+// RequireNoFollowOnFullyQualifiedLinks will result in all a, area, and link
+// tags that point to a non-local destination (i.e. starts with a protocol and
+// has a host) having a rel="nofollow" added to them if one does not already
+// exist
 //
 // Note: This requires p.RequireParseableURLs(true) and will enable it.
 func (p *Policy) RequireNoFollowOnFullyQualifiedLinks(require bool) *Policy {
@@ -307,9 +589,45 @@ func (p *Policy) RequireNoFollowOnFullyQualifiedLinks(require bool) *Policy {
 	return p
 }
 
-// AddTargetBlankToFullyQualifiedLinks will result in all <a> tags that point
-// to a non-local destination (i.e. starts with a protocol and has a host)
-// having a target="_blank" added to them if one does not already exist
+// RequireNoReferrerOnLinks will result in all a, area, and link tags having a
+// rel="noreferrrer" added to them if one does not already exist
+//
+// Note: This requires p.RequireParseableURLs(true) and will enable it.
+func (p *Policy) RequireNoReferrerOnLinks(require bool) *Policy {
+
+	p.requireNoReferrer = require
+	p.requireParseableURLs = true
+
+	return p
+}
+
+// RequireNoReferrerOnFullyQualifiedLinks will result in all a, area, and link
+// tags that point to a non-local destination (i.e. starts with a protocol and
+// has a host) having a rel="noreferrer" added to them if one does not already
+// exist
+//
+// Note: This requires p.RequireParseableURLs(true) and will enable it.
+func (p *Policy) RequireNoReferrerOnFullyQualifiedLinks(require bool) *Policy {
+
+	p.requireNoReferrerFullyQualifiedLinks = require
+	p.requireParseableURLs = true
+
+	return p
+}
+
+// RequireCrossOriginAnonymous will result in all audio, img, link, script, and
+// video tags having a crossorigin="anonymous" added to them if one does not
+// already exist
+func (p *Policy) RequireCrossOriginAnonymous(require bool) *Policy {
+
+	p.requireCrossOriginAnonymous = require
+
+	return p
+}
+
+// AddTargetBlankToFullyQualifiedLinks will result in all a, area and link tags
+// that point to a non-local destination (i.e. starts with a protocol and has a
+// host) having a target="_blank" added to them if one does not already exist
 //
 // Note: This requires p.RequireParseableURLs(true) and will enable it.
 func (p *Policy) AddTargetBlankToFullyQualifiedLinks(require bool) *Policy {
@@ -347,7 +665,7 @@ func (p *Policy) AllowRelativeURLs(require bool) *Policy {
 	return p
 }
 
-// AllowURLSchemes will append URL schemes to the whitelist
+// AllowURLSchemes will append URL schemes to the allowlist
 // Example: p.AllowURLSchemes("mailto", "http", "https")
 func (p *Policy) AllowURLSchemes(schemes ...string) *Policy {
 	p.init()
@@ -365,7 +683,7 @@ func (p *Policy) AllowURLSchemes(schemes ...string) *Policy {
 }
 
 // AllowURLSchemeWithCustomPolicy will append URL schemes with
-// a custom URL policy to the whitelist.
+// a custom URL policy to the allowlist.
 // Only the URLs with matching schema and urlPolicy(url)
 // returning true will be allowed.
 func (p *Policy) AllowURLSchemeWithCustomPolicy(
@@ -379,13 +697,65 @@ func (p *Policy) AllowURLSchemeWithCustomPolicy(
 
 	scheme = strings.ToLower(scheme)
 
-	p.allowURLSchemes[scheme] = urlPolicy
+	p.allowURLSchemes[scheme] = append(p.allowURLSchemes[scheme], urlPolicy)
 
 	return p
 }
 
+// RequireSandboxOnIFrame will result in all iframe tags having a sandbox="" tag
+// Any sandbox values not specified here will be filtered from the generated HTML
+func (p *Policy) RequireSandboxOnIFrame(vals ...SandboxValue) {
+	p.requireSandboxOnIFrame = make(map[string]bool)
+
+	for val := range vals {
+		switch SandboxValue(val) {
+		case SandboxAllowDownloads:
+			p.requireSandboxOnIFrame["allow-downloads"] = true
+
+		case SandboxAllowDownloadsWithoutUserActivation:
+			p.requireSandboxOnIFrame["allow-downloads-without-user-activation"] = true
+
+		case SandboxAllowForms:
+			p.requireSandboxOnIFrame["allow-forms"] = true
+
+		case SandboxAllowModals:
+			p.requireSandboxOnIFrame["allow-modals"] = true
+
+		case SandboxAllowOrientationLock:
+			p.requireSandboxOnIFrame["allow-orientation-lock"] = true
+
+		case SandboxAllowPointerLock:
+			p.requireSandboxOnIFrame["allow-pointer-lock"] = true
+
+		case SandboxAllowPopups:
+			p.requireSandboxOnIFrame["allow-popups"] = true
+
+		case SandboxAllowPopupsToEscapeSandbox:
+			p.requireSandboxOnIFrame["allow-popups-to-escape-sandbox"] = true
+
+		case SandboxAllowPresentation:
+			p.requireSandboxOnIFrame["allow-presentation"] = true
+
+		case SandboxAllowSameOrigin:
+			p.requireSandboxOnIFrame["allow-same-origin"] = true
+
+		case SandboxAllowScripts:
+			p.requireSandboxOnIFrame["allow-scripts"] = true
+
+		case SandboxAllowStorageAccessByUserActivation:
+			p.requireSandboxOnIFrame["allow-storage-access-by-user-activation"] = true
+
+		case SandboxAllowTopNavigation:
+			p.requireSandboxOnIFrame["allow-top-navigation"] = true
+
+		case SandboxAllowTopNavigationByUserActivation:
+			p.requireSandboxOnIFrame["allow-top-navigation-by-user-activation"] = true
+		}
+	}
+}
+
 // AddSpaceWhenStrippingTag states whether to add a single space " " when
-// removing tags that are not whitelisted by the policy.
+// removing tags that are not allowed by the policy.
 //
 // This is useful if you expect to strip tags in dense markup and may lose the
 // value of whitespace.
@@ -431,6 +801,23 @@ func (p *Policy) AllowElementsContent(names ...string) *Policy {
 	return p
 }
 
+// AllowUnsafe permits fundamentally unsafe elements.
+//
+// If false (default) then elements such as `style` and `script` will not be
+// permitted even if declared in a policy. These elements when combined with
+// untrusted input cannot be safely handled by bluemonday at this point in
+// time.
+//
+// If true then `style` and `script` would be permitted by bluemonday if a
+// policy declares them. However this is not recommended under any circumstance
+// and can lead to XSS being rendered thus defeating the purpose of using a
+// HTML sanitizer.
+func (p *Policy) AllowUnsafe(allowUnsafe bool) *Policy {
+	p.init()
+	p.allowUnsafe = allowUnsafe
+	return p
+}
+
 // addDefaultElementsWithoutAttrs adds the HTML elements that we know are valid
 // without any attributes to an internal map.
 // i.e. we know that <table> is valid, but <bdo> isn't valid as the "dir" attr

vendor/github.com/microcosm-cc/bluemonday/stringwriterwriter_go1.12.go

@@ -0,0 +1,11 @@
+//go:build go1.12
+// +build go1.12
+
+package bluemonday
+
+import "io"
+
+type stringWriterWriter interface {
+	io.Writer
+	io.StringWriter
+}

vendor/github.com/microcosm-cc/bluemonday/stringwriterwriter_ltgo1.12.go

@@ -0,0 +1,15 @@
+//go:build go1.1 && !go1.12
+// +build go1.1,!go1.12
+
+package bluemonday
+
+import "io"
+
+type stringWriterWriter interface {
+	io.Writer
+	StringWriter
+}
+
+type StringWriter interface {
+	WriteString(s string) (n int, err error)
+}

vendor/golang.org/x/net/context/go17.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build go1.7
 // +build go1.7
 
 package context

vendor/golang.org/x/net/context/go19.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build go1.9
 // +build go1.9
 
 package context

vendor/golang.org/x/net/context/pre_go17.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !go1.7
 // +build !go1.7
 
 package context

vendor/golang.org/x/net/context/pre_go19.go

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+//go:build !go1.9
 // +build !go1.9
 
 package context

vendor/golang.org/x/net/html/const.go

@@ -52,7 +52,7 @@ var isSpecialElementMap = map[string]bool{
 	"iframe":     true,
 	"img":        true,
 	"input":      true,
-	"keygen":     true,
+	"keygen":     true, // "keygen" has been removed from the spec, but are kept here for backwards compatibility.
 	"li":         true,
 	"link":       true,
 	"listing":    true,

vendor/golang.org/x/net/html/foreign.go

@@ -161,65 +161,62 @@ var mathMLAttributeAdjustments = map[string]string{
 }
 
 var svgAttributeAdjustments = map[string]string{
-	"attributename":             "attributeName",
-	"attributetype":             "attributeType",
-	"basefrequency":             "baseFrequency",
-	"baseprofile":               "baseProfile",
-	"calcmode":                  "calcMode",
-	"clippathunits":             "clipPathUnits",
-	"contentscripttype":         "contentScriptType",
-	"contentstyletype":          "contentStyleType",
-	"diffuseconstant":           "diffuseConstant",
-	"edgemode":                  "edgeMode",
-	"externalresourcesrequired": "externalResourcesRequired",
-	"filterunits":               "filterUnits",
-	"glyphref":                  "glyphRef",
-	"gradienttransform":         "gradientTransform",
-	"gradientunits":             "gradientUnits",
-	"kernelmatrix":              "kernelMatrix",
-	"kernelunitlength":          "kernelUnitLength",
-	"keypoints":                 "keyPoints",
-	"keysplines":                "keySplines",
-	"keytimes":                  "keyTimes",
-	"lengthadjust":              "lengthAdjust",
-	"limitingconeangle":         "limitingConeAngle",
-	"markerheight":              "markerHeight",
-	"markerunits":               "markerUnits",
-	"markerwidth":               "markerWidth",
-	"maskcontentunits":          "maskContentUnits",
-	"maskunits":                 "maskUnits",
-	"numoctaves":                "numOctaves",
-	"pathlength":                "pathLength",
-	"patterncontentunits":       "patternContentUnits",
-	"patterntransform":          "patternTransform",
-	"patternunits":              "patternUnits",
-	"pointsatx":                 "pointsAtX",
-	"pointsaty":                 "pointsAtY",
-	"pointsatz":                 "pointsAtZ",
-	"preservealpha":             "preserveAlpha",
-	"preserveaspectratio":       "preserveAspectRatio",
-	"primitiveunits":            "primitiveUnits",
-	"refx":                      "refX",
-	"refy":                      "refY",
-	"repeatcount":               "repeatCount",
-	"repeatdur":                 "repeatDur",
-	"requiredextensions":        "requiredExtensions",
-	"requiredfeatures":          "requiredFeatures",
-	"specularconstant":          "specularConstant",
-	"specularexponent":          "specularExponent",
-	"spreadmethod":              "spreadMethod",
-	"startoffset":               "startOffset",
-	"stddeviation":              "stdDeviation",
-	"stitchtiles":               "stitchTiles",
-	"surfacescale":              "surfaceScale",
-	"systemlanguage":            "systemLanguage",
-	"tablevalues":               "tableValues",
-	"targetx":                   "targetX",
-	"targety":                   "targetY",
-	"textlength":                "textLength",
-	"viewbox":                   "viewBox",
-	"viewtarget":                "viewTarget",
-	"xchannelselector":          "xChannelSelector",
-	"ychannelselector":          "yChannelSelector",
-	"zoomandpan":                "zoomAndPan",
+	"attributename":       "attributeName",
+	"attributetype":       "attributeType",
+	"basefrequency":       "baseFrequency",
+	"baseprofile":         "baseProfile",
+	"calcmode":            "calcMode",
+	"clippathunits":       "clipPathUnits",
+	"diffuseconstant":     "diffuseConstant",
+	"edgemode":            "edgeMode",
+	"filterunits":         "filterUnits",
+	"glyphref":            "glyphRef",
+	"gradienttransform":   "gradientTransform",
+	"gradientunits":       "gradientUnits",
+	"kernelmatrix":        "kernelMatrix",
+	"kernelunitlength":    "kernelUnitLength",
+	"keypoints":           "keyPoints",
+	"keysplines":          "keySplines",
+	"keytimes":            "keyTimes",
+	"lengthadjust":        "lengthAdjust",
+	"limitingconeangle":   "limitingConeAngle",
+	"markerheight":        "markerHeight",
+	"markerunits":         "markerUnits",
+	"markerwidth":         "markerWidth",
+	"maskcontentunits":    "maskContentUnits",
+	"maskunits":           "maskUnits",
+	"numoctaves":          "numOctaves",
+	"pathlength":          "pathLength",
+	"patterncontentunits": "patternContentUnits",
+	"patterntransform":    "patternTransform",
+	"patternunits":        "patternUnits",
+	"pointsatx":           "pointsAtX",
+	"pointsaty":           "pointsAtY",
+	"pointsatz":           "pointsAtZ",
+	"preservealpha":       "preserveAlpha",
+	"preserveaspectratio": "preserveAspectRatio",
+	"primitiveunits":      "primitiveUnits",
+	"refx":                "refX",
+	"refy":                "refY",
+	"repeatcount":         "repeatCount",
+	"repeatdur":           "repeatDur",
+	"requiredextensions":  "requiredExtensions",
+	"requiredfeatures":    "requiredFeatures",
+	"specularconstant":    "specularConstant",
+	"specularexponent":    "specularExponent",
+	"spreadmethod":        "spreadMethod",
+	"startoffset":         "startOffset",
+	"stddeviation":        "stdDeviation",
+	"stitchtiles":         "stitchTiles",
+	"surfacescale":        "surfaceScale",
+	"systemlanguage":      "systemLanguage",
+	"tablevalues":         "tableValues",
+	"targetx":             "targetX",
+	"targety":             "targetY",
+	"textlength":          "textLength",
+	"viewbox":             "viewBox",
+	"viewtarget":          "viewTarget",
+	"xchannelselector":    "xChannelSelector",
+	"ychannelselector":    "yChannelSelector",
+	"zoomandpan":          "zoomAndPan",
 }

vendor/golang.org/x/net/html/parse.go

@@ -663,6 +663,24 @@ func inHeadIM(p *parser) bool {
 			// Ignore the token.
 			return true
 		case a.Template:
+			// TODO: remove this divergence from the HTML5 spec.
+			//
+			// We don't handle all of the corner cases when mixing foreign
+			// content (i.e. <math> or <svg>) with <template>. Without this
+			// early return, we can get into an infinite loop, possibly because
+			// of the "TODO... further divergence" a little below.
+			//
+			// As a workaround, if we are mixing foreign content and templates,
+			// just ignore the rest of the HTML. Foreign content is rare and a
+			// relatively old HTML feature. Templates are also rare and a
+			// relatively new HTML feature. Their combination is very rare.
+			for _, e := range p.oe {
+				if e.Namespace != "" {
+					p.im = ignoreTheRemainingTokens
+					return true
+				}
+			}
+
 			p.addElement()
 			p.afe = append(p.afe, &scopeMarker)
 			p.framesetOK = false
@@ -683,7 +701,7 @@ func inHeadIM(p *parser) bool {
 			if !p.oe.contains(a.Template) {
 				return true
 			}
-			// TODO: remove this divergence from the HTML5 spec.
+			// TODO: remove this further divergence from the HTML5 spec.
 			//
 			// See https://bugs.chromium.org/p/chromium/issues/detail?id=829668
 			p.generateImpliedEndTags()
@@ -728,7 +746,13 @@ func inHeadNoscriptIM(p *parser) bool {
 			return inBodyIM(p)
 		case a.Basefont, a.Bgsound, a.Link, a.Meta, a.Noframes, a.Style:
 			return inHeadIM(p)
-		case a.Head, a.Noscript:
+		case a.Head:
+			// Ignore the token.
+			return true
+		case a.Noscript:
+			// Don't let the tokenizer go into raw text mode even when a <noscript>
+			// tag is in "in head noscript" insertion mode.
+			p.tokenizer.NextIsNotRawText()
 			// Ignore the token.
 			return true
 		}
@@ -1790,6 +1814,13 @@ func inSelectIM(p *parser) bool {
 			return true
 		case a.Script, a.Template:
 			return inHeadIM(p)
+		case a.Iframe, a.Noembed, a.Noframes, a.Noscript, a.Plaintext, a.Style, a.Title, a.Xmp:
+			// Don't let the tokenizer go into raw text mode when there are raw tags
+			// to be ignored. These tags should be ignored from the tokenizer
+			// properly.
+			p.tokenizer.NextIsNotRawText()
+			// Ignore the token.
+			return true
 		}
 	case EndTagToken:
 		switch p.tok.DataAtom {
@@ -2114,6 +2145,10 @@ func afterAfterFramesetIM(p *parser) bool {
 	return true
 }
 
+func ignoreTheRemainingTokens(p *parser) bool {
+	return true
+}
+
 const whitespaceOrNUL = whitespace + "\x00"
 
 // Section 12.2.6.5

vendor/golang.org/x/net/html/render.go

@@ -263,7 +263,7 @@ var voidElements = map[string]bool{
 	"hr":     true,
 	"img":    true,
 	"input":  true,
-	"keygen": true,
+	"keygen": true, // "keygen" has been removed from the spec, but are kept here for backwards compatibility.
 	"link":   true,
 	"meta":   true,
 	"param":  true,

vendor/modules.txt

@@ -7,6 +7,10 @@ github.com/BurntSushi/toml
 # github.com/andygrunwald/go-jira v1.12.0
 ## explicit; go 1.12
 github.com/andygrunwald/go-jira
+# github.com/aymerick/douceur v0.2.0
+## explicit
+github.com/aymerick/douceur/css
+github.com/aymerick/douceur/parser
 # github.com/codegangsta/negroni v1.0.0
 ## explicit
 github.com/codegangsta/negroni
@@ -59,6 +63,9 @@ github.com/google/go-github/github
 # github.com/google/go-querystring v1.0.0
 ## explicit
 github.com/google/go-querystring/query
+# github.com/gorilla/css v1.0.0
+## explicit
+github.com/gorilla/css/scanner
 # github.com/gorilla/handlers v1.4.2
 ## explicit
 github.com/gorilla/handlers
@@ -79,9 +86,10 @@ github.com/lib/pq/scram
 # github.com/mb0/diff v0.0.0-20131118162322-d8d9a906c24d
 ## explicit
 github.com/mb0/diff
-# github.com/microcosm-cc/bluemonday v1.0.2
-## explicit; go 1.9
+# github.com/microcosm-cc/bluemonday v1.0.17
+## explicit; go 1.16
 github.com/microcosm-cc/bluemonday
+github.com/microcosm-cc/bluemonday/css
 # github.com/nu7hatch/gouuid v0.0.0-20131221200532-179d4d0c4d8d
 ## explicit
 github.com/nu7hatch/gouuid
@@ -103,8 +111,8 @@ github.com/trivago/tgo/treflect
 golang.org/x/crypto/bcrypt
 golang.org/x/crypto/blowfish
 golang.org/x/crypto/md4
-# golang.org/x/net v0.0.0-20200520182314-0ba52f642ac2
-## explicit; go 1.11
+# golang.org/x/net v0.0.0-20210614182718-04defd469f4e
+## explicit; go 1.17
 golang.org/x/net/context
 golang.org/x/net/context/ctxhttp
 golang.org/x/net/html