跨站脚本攻击
This commit is contained in:
liwu0213
2017-03-15 12:45:03 +08:00
committed by GitHub
parent b408af99dc
commit 90d8258b4e
35 changed files with 6379 additions and 2 deletions

48
lib/cli.js Normal file
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/**
* 命令行测试工具
*
* @author 老雷<leizongmin@gmail.com>
*/
var xss = require('./');
var readline = require('readline');
var rl = readline.createInterface({
input: process.stdin,
output: process.stdout
});
console.log('Enter a blank line to do xss(), enter "@quit" to exit.\n');
function take (c, n) {
var ret = '';
for (var i = 0; i < n; i++) {
ret += c;
}
return ret;
}
function setPrompt (line) {
line = line.toString();
rl.setPrompt('[' + line + ']' + take(' ', 5 - line.length));
rl.prompt();
}
setPrompt(1);
var html = [];
rl.on('line', function (line) {
if (line === '@quit') return process.exit();
if (line === '') {
console.log('');
console.log(xss(html.join('\r\n')));
console.log('');
html = [];
} else {
html.push(line);
}
setPrompt(html.length + 1);
});

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lib/default.js Normal file
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/**
* 默认配置
*
* @author 老雷<leizongmin@gmail.com>
*/
var FilterCSS = require('cssfilter').FilterCSS;
var getDefaultCSSWhiteList = require('cssfilter').getDefaultWhiteList;
var _ = require('./util');
// 默认白名单
function getDefaultWhiteList () {
return {
a: ['target', 'href', 'title'],
abbr: ['title'],
address: [],
area: ['shape', 'coords', 'href', 'alt'],
article: [],
aside: [],
audio: ['autoplay', 'controls', 'loop', 'preload', 'src'],
b: [],
bdi: ['dir'],
bdo: ['dir'],
big: [],
blockquote: ['cite'],
br: [],
caption: [],
center: [],
cite: [],
code: [],
col: ['align', 'valign', 'span', 'width'],
colgroup: ['align', 'valign', 'span', 'width'],
dd: [],
del: ['datetime'],
details: ['open'],
div: [],
dl: [],
dt: [],
em: [],
font: ['color', 'size', 'face'],
footer: [],
h1: [],
h2: [],
h3: [],
h4: [],
h5: [],
h6: [],
header: [],
hr: [],
i: [],
img: ['src', 'alt', 'title', 'width', 'height'],
ins: ['datetime'],
li: [],
mark: [],
nav: [],
ol: [],
p: [],
pre: [],
s: [],
section:[],
small: [],
span: [],
sub: [],
sup: [],
strong: [],
table: ['width', 'border', 'align', 'valign'],
tbody: ['align', 'valign'],
td: ['width', 'rowspan', 'colspan', 'align', 'valign'],
tfoot: ['align', 'valign'],
th: ['width', 'rowspan', 'colspan', 'align', 'valign'],
thead: ['align', 'valign'],
tr: ['rowspan', 'align', 'valign'],
tt: [],
u: [],
ul: [],
video: ['autoplay', 'controls', 'loop', 'preload', 'src', 'height', 'width']
};
}
// 默认CSS Filter
var defaultCSSFilter = new FilterCSS();
/**
* 匹配到标签时的处理方法
*
* @param {String} tag
* @param {String} html
* @param {Object} options
* @return {String}
*/
function onTag (tag, html, options) {
// do nothing
}
/**
* 匹配到不在白名单上的标签时的处理方法
*
* @param {String} tag
* @param {String} html
* @param {Object} options
* @return {String}
*/
function onIgnoreTag (tag, html, options) {
// do nothing
}
/**
* 匹配到标签属性时的处理方法
*
* @param {String} tag
* @param {String} name
* @param {String} value
* @return {String}
*/
function onTagAttr (tag, name, value) {
// do nothing
}
/**
* 匹配到不在白名单上的标签属性时的处理方法
*
* @param {String} tag
* @param {String} name
* @param {String} value
* @return {String}
*/
function onIgnoreTagAttr (tag, name, value) {
// do nothing
}
/**
* HTML转义
*
* @param {String} html
*/
function escapeHtml (html) {
return html.replace(REGEXP_LT, '&lt;').replace(REGEXP_GT, '&gt;');
}
/**
* 安全的标签属性值
*
* @param {String} tag
* @param {String} name
* @param {String} value
* @param {Object} cssFilter
* @return {String}
*/
function safeAttrValue (tag, name, value, cssFilter) {
// 转换为友好的属性值,再做判断
value = friendlyAttrValue(value);
if (name === 'href' || name === 'src') {
// 过滤 href 和 src 属性
// 仅允许 http:// | https:// | mailto: | / | # 开头的地址
value = _.trim(value);
if (value === '#') return '#';
if (!(value.substr(0, 7) === 'http://' ||
value.substr(0, 8) === 'https://' ||
value.substr(0, 7) === 'mailto:' ||
value[0] === '#' ||
value[0] === '/')) {
return '';
}
} else if (name === 'background') {
// 过滤 background 属性 这个xss漏洞较老了可能已经不适用
// javascript:
REGEXP_DEFAULT_ON_TAG_ATTR_4.lastIndex = 0;
if (REGEXP_DEFAULT_ON_TAG_ATTR_4.test(value)) {
return '';
}
} else if (name === 'style') {
// /*注释*/
/*REGEXP_DEFAULT_ON_TAG_ATTR_3.lastIndex = 0;
if (REGEXP_DEFAULT_ON_TAG_ATTR_3.test(value)) {
return '';
}*/
// expression()
REGEXP_DEFAULT_ON_TAG_ATTR_7.lastIndex = 0;
if (REGEXP_DEFAULT_ON_TAG_ATTR_7.test(value)) {
return '';
}
// url()
REGEXP_DEFAULT_ON_TAG_ATTR_8.lastIndex = 0;
if (REGEXP_DEFAULT_ON_TAG_ATTR_8.test(value)) {
REGEXP_DEFAULT_ON_TAG_ATTR_4.lastIndex = 0;
if (REGEXP_DEFAULT_ON_TAG_ATTR_4.test(value)) {
return '';
}
}
if (cssFilter !== false) {
cssFilter = cssFilter || defaultCSSFilter;
value = cssFilter.process(value);
}
}
// 输出时需要转义<>"
value = escapeAttrValue(value);
return value;
}
// 正则表达式
var REGEXP_LT = /</g;
var REGEXP_GT = />/g;
var REGEXP_QUOTE = /"/g;
var REGEXP_QUOTE_2 = /&quot;/g;
var REGEXP_ATTR_VALUE_1 = /&#([a-zA-Z0-9]*);?/img;
var REGEXP_ATTR_VALUE_COLON = /&colon;?/img;
var REGEXP_ATTR_VALUE_NEWLINE = /&newline;?/img;
var REGEXP_DEFAULT_ON_TAG_ATTR_3 = /\/\*|\*\//mg;
var REGEXP_DEFAULT_ON_TAG_ATTR_4 = /((j\s*a\s*v\s*a|v\s*b|l\s*i\s*v\s*e)\s*s\s*c\s*r\s*i\s*p\s*t\s*|m\s*o\s*c\s*h\s*a)\:/ig;
var REGEXP_DEFAULT_ON_TAG_ATTR_5 = /^[\s"'`]*(d\s*a\s*t\s*a\s*)\:/ig;
var REGEXP_DEFAULT_ON_TAG_ATTR_6 = /^[\s"'`]*(d\s*a\s*t\s*a\s*)\:\s*image\//ig;
var REGEXP_DEFAULT_ON_TAG_ATTR_7 = /e\s*x\s*p\s*r\s*e\s*s\s*s\s*i\s*o\s*n\s*\(.*/ig;
var REGEXP_DEFAULT_ON_TAG_ATTR_8 = /u\s*r\s*l\s*\(.*/ig;
/**
* 对双引号进行转义
*
* @param {String} str
* @return {String} str
*/
function escapeQuote (str) {
return str.replace(REGEXP_QUOTE, '&quot;');
}
/**
* 对双引号进行转义
*
* @param {String} str
* @return {String} str
*/
function unescapeQuote (str) {
return str.replace(REGEXP_QUOTE_2, '"');
}
/**
* 对html实体编码进行转义
*
* @param {String} str
* @return {String}
*/
function escapeHtmlEntities (str) {
return str.replace(REGEXP_ATTR_VALUE_1, function replaceUnicode (str, code) {
return (code[0] === 'x' || code[0] === 'X')
? String.fromCharCode(parseInt(code.substr(1), 16))
: String.fromCharCode(parseInt(code, 10));
});
}
/**
* 对html5新增的危险实体编码进行转义
*
* @param {String} str
* @return {String}
*/
function escapeDangerHtml5Entities (str) {
return str.replace(REGEXP_ATTR_VALUE_COLON, ':')
.replace(REGEXP_ATTR_VALUE_NEWLINE, ' ');
}
/**
* 清除不可见字符
*
* @param {String} str
* @return {String}
*/
function clearNonPrintableCharacter (str) {
var str2 = '';
for (var i = 0, len = str.length; i < len; i++) {
str2 += str.charCodeAt(i) < 32 ? ' ' : str.charAt(i);
}
return _.trim(str2);
}
/**
* 将标签的属性值转换成一般字符,便于分析
*
* @param {String} str
* @return {String}
*/
function friendlyAttrValue (str) {
str = unescapeQuote(str); // 双引号
str = escapeHtmlEntities(str); // 转换HTML实体编码
str = escapeDangerHtml5Entities(str); // 转换危险的HTML5新增实体编码
str = clearNonPrintableCharacter(str); // 清除不可见字符
return str;
}
/**
* 转义用于输出的标签属性值
*
* @param {String} str
* @return {String}
*/
function escapeAttrValue (str) {
str = escapeQuote(str);
str = escapeHtml(str);
return str;
}
/**
* 去掉不在白名单中的标签onIgnoreTag处理方法
*/
function onIgnoreTagStripAll () {
return '';
}
/**
* 删除标签体
*
* @param {array} tags 要删除的标签列表
* @param {function} next 对不在列表中的标签的处理函数,可选
*/
function StripTagBody (tags, next) {
if (typeof(next) !== 'function') {
next = function () {};
}
var isRemoveAllTag = !Array.isArray(tags);
function isRemoveTag (tag) {
if (isRemoveAllTag) return true;
return (_.indexOf(tags, tag) !== -1);
}
var removeList = []; // 要删除的位置范围列表
var posStart = false; // 当前标签开始位置
return {
onIgnoreTag: function (tag, html, options) {
if (isRemoveTag(tag)) {
if (options.isClosing) {
var ret = '[/removed]';
var end = options.position + ret.length;
removeList.push([posStart !== false ? posStart : options.position, end]);
posStart = false;
return ret;
} else {
if (!posStart) {
posStart = options.position;
}
return '[removed]';
}
} else {
return next(tag, html, options);
}
},
remove: function (html) {
var rethtml = '';
var lastPos = 0;
_.forEach(removeList, function (pos) {
rethtml += html.slice(lastPos, pos[0]);
lastPos = pos[1];
});
rethtml += html.slice(lastPos);
return rethtml;
}
};
}
/**
* 去除备注标签
*
* @param {String} html
* @return {String}
*/
function stripCommentTag (html) {
return html.replace(STRIP_COMMENT_TAG_REGEXP, '');
}
var STRIP_COMMENT_TAG_REGEXP = /<!--[\s\S]*?-->/g;
/**
* 去除不可见字符
*
* @param {String} html
* @return {String}
*/
function stripBlankChar (html) {
var chars = html.split('');
chars = chars.filter(function (char) {
var c = char.charCodeAt(0);
if (c === 127) return false;
if (c <= 31) {
if (c === 10 || c === 13) return true;
return false;
}
return true;
});
return chars.join('');
}
exports.whiteList = getDefaultWhiteList();
exports.getDefaultWhiteList = getDefaultWhiteList;
exports.onTag = onTag;
exports.onIgnoreTag = onIgnoreTag;
exports.onTagAttr = onTagAttr;
exports.onIgnoreTagAttr = onIgnoreTagAttr;
exports.safeAttrValue = safeAttrValue;
exports.escapeHtml = escapeHtml;
exports.escapeQuote = escapeQuote;
exports.unescapeQuote = unescapeQuote;
exports.escapeHtmlEntities = escapeHtmlEntities;
exports.escapeDangerHtml5Entities = escapeDangerHtml5Entities;
exports.clearNonPrintableCharacter = clearNonPrintableCharacter;
exports.friendlyAttrValue = friendlyAttrValue;
exports.escapeAttrValue = escapeAttrValue;
exports.onIgnoreTagStripAll = onIgnoreTagStripAll;
exports.StripTagBody = StripTagBody;
exports.stripCommentTag = stripCommentTag;
exports.stripBlankChar = stripBlankChar;
exports.cssFilter = defaultCSSFilter;
exports.getDefaultCSSWhiteList = getDefaultCSSWhiteList;

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/**
* 模块入口
*
* @author 老雷<leizongmin@gmail.com>
*/
var DEFAULT = require('./default');
var parser = require('./parser');
var FilterXSS = require('./xss');
/**
* XSS过滤
*
* @param {String} html 要过滤的HTML代码
* @param {Object} options 选项whiteList, onTag, onTagAttr, onIgnoreTag, onIgnoreTagAttr, safeAttrValue, escapeHtml
* @return {String}
*/
function filterXSS (html, options) {
var xss = new FilterXSS(options);
return xss.process(html);
}
// 输出
exports = module.exports = filterXSS;
exports.FilterXSS = FilterXSS;
for (var i in DEFAULT) exports[i] = DEFAULT[i];
for (var i in parser) exports[i] = parser[i];
// 在浏览器端使用
if (typeof window !== 'undefined') {
window.filterXSS = module.exports;
}

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/**
* 简单 HTML Parser
*
* @author 老雷<leizongmin@gmail.com>
*/
var _ = require('./util');
/**
* 获取标签的名称
*
* @param {String} html 如:'<a hef="#">'
* @return {String}
*/
function getTagName (html) {
var i = html.indexOf(' ');
if (i === -1) {
var tagName = html.slice(1, -1);
} else {
var tagName = html.slice(1, i + 1);
}
tagName = _.trim(tagName).toLowerCase();
if (tagName.slice(0, 1) === '/') tagName = tagName.slice(1);
if (tagName.slice(-1) === '/') tagName = tagName.slice(0, -1);
return tagName;
}
/**
* 是否为闭合标签
*
* @param {String} html 如:'<a hef="#">'
* @return {Boolean}
*/
function isClosing (html) {
return (html.slice(0, 2) === '</');
}
/**
* 分析HTML代码调用相应的函数处理返回处理后的HTML
*
* @param {String} html
* @param {Function} onTag 处理标签的函数
* 参数格式: function (sourcePosition, position, tag, html, isClosing)
* @param {Function} escapeHtml 对HTML进行转义的函数
* @return {String}
*/
function parseTag (html, onTag, escapeHtml) {
'user strict';
var rethtml = ''; // 待返回的HTML
var lastPos = 0; // 上一个标签结束位置
var tagStart = false; // 当前标签开始位置
var quoteStart = false; // 引号开始位置
var currentPos = 0; // 当前位置
var len = html.length; // HTML长度
var currentHtml = ''; // 当前标签的HTML代码
var currentTagName = ''; // 当前标签的名称
// 逐个分析字符
for (currentPos = 0; currentPos < len; currentPos++) {
var c = html.charAt(currentPos);
if (tagStart === false) {
if (c === '<') {
tagStart = currentPos;
continue;
}
} else {
if (quoteStart === false) {
if (c === '<') {
rethtml += escapeHtml(html.slice(lastPos, currentPos));
tagStart = currentPos;
lastPos = currentPos;
continue;
}
if (c === '>') {
rethtml += escapeHtml(html.slice(lastPos, tagStart));
currentHtml = html.slice(tagStart, currentPos + 1);
currentTagName = getTagName(currentHtml);
rethtml += onTag(tagStart,
rethtml.length,
currentTagName,
currentHtml,
isClosing(currentHtml));
lastPos = currentPos + 1;
tagStart = false;
continue;
}
// HTML标签内的引号仅当前一个字符是等于号时才有效
if ((c === '"' || c === "'") && html.charAt(currentPos - 1) === '=') {
quoteStart = c;
continue;
}
} else {
if (c === quoteStart) {
quoteStart = false;
continue;
}
}
}
}
if (lastPos < html.length) {
rethtml += escapeHtml(html.substr(lastPos));
}
return rethtml;
}
// 不符合属性名称规则的正则表达式
var REGEXP_ATTR_NAME = /[^a-zA-Z0-9_:\.\-]/img;
/**
* 分析标签HTML代码调用相应的函数处理返回HTML
*
* @param {String} html 如标签'<a href="#" target="_blank">' 则为 'href="#" target="_blank"'
* @param {Function} onAttr 处理属性值的函数
* 函数格式: function (name, value)
* @return {String}
*/
function parseAttr (html, onAttr) {
'user strict';
var lastPos = 0; // 当前位置
var retAttrs = []; // 待返回的属性列表
var tmpName = false; // 临时属性名称
var len = html.length; // HTML代码长度
function addAttr (name, value) {
name = _.trim(name);
name = name.replace(REGEXP_ATTR_NAME, '').toLowerCase();
if (name.length < 1) return;
var ret = onAttr(name, value || '');
if (ret) retAttrs.push(ret);
};
// 逐个分析字符
for (var i = 0; i < len; i++) {
var c = html.charAt(i);
var v, j;
if (tmpName === false && c === '=') {
tmpName = html.slice(lastPos, i);
lastPos = i + 1;
continue;
}
if (tmpName !== false) {
// HTML标签内的引号仅当前一个字符是等于号时才有效
if (i === lastPos && (c === '"' || c === "'") && html.charAt(i - 1) === '=') {
j = html.indexOf(c, i + 1);
if (j === -1) {
break;
} else {
v = _.trim(html.slice(lastPos + 1, j));
addAttr(tmpName, v);
tmpName = false;
i = j;
lastPos = i + 1;
continue;
}
}
}
if (c === ' ') {
if (tmpName === false) {
j = findNextEqual(html, i);
if (j === -1) {
v = _.trim(html.slice(lastPos, i));
addAttr(v);
tmpName = false;
lastPos = i + 1;
continue;
} else {
i = j - 1;
continue;
}
} else {
j = findBeforeEqual(html, i - 1);
if (j === -1) {
v = _.trim(html.slice(lastPos, i));
v = stripQuoteWrap(v);
addAttr(tmpName, v);
tmpName = false;
lastPos = i + 1;
continue;
} else {
continue;
}
}
}
}
if (lastPos < html.length) {
if (tmpName === false) {
addAttr(html.slice(lastPos));
} else {
addAttr(tmpName, stripQuoteWrap(_.trim(html.slice(lastPos))));
}
}
return _.trim(retAttrs.join(' '));
}
function findNextEqual (str, i) {
for (; i < str.length; i++) {
var c = str[i];
if (c === ' ') continue;
if (c === '=') return i;
return -1;
}
}
function findBeforeEqual (str, i) {
for (; i > 0; i--) {
var c = str[i];
if (c === ' ') continue;
if (c === '=') return i;
return -1;
}
}
function isQuoteWrapString (text) {
if ((text[0] === '"' && text[text.length - 1] === '"') ||
(text[0] === '\'' && text[text.length - 1] === '\'')) {
return true;
} else {
return false;
}
};
function stripQuoteWrap (text) {
if (isQuoteWrapString(text)) {
return text.substr(1, text.length - 2);
} else {
return text;
}
};
exports.parseTag = parseTag;
exports.parseAttr = parseAttr;

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module.exports = {
indexOf: function (arr, item) {
var i, j;
if (Array.prototype.indexOf) {
return arr.indexOf(item);
}
for (i = 0, j = arr.length; i < j; i++) {
if (arr[i] === item) {
return i;
}
}
return -1;
},
forEach: function (arr, fn, scope) {
var i, j;
if (Array.prototype.forEach) {
return arr.forEach(fn, scope);
}
for (i = 0, j = arr.length; i < j; i++) {
fn.call(scope, arr[i], i, arr);
}
},
trim: function (str) {
if (String.prototype.trim) {
return str.trim();
}
return str.replace(/(^\s*)|(\s*$)/g, '');
}
};

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/**
* 过滤XSS
*
* @author 老雷<leizongmin@gmail.com>
*/
var FilterCSS = require('cssfilter').FilterCSS;
var DEFAULT = require('./default');
var parser = require('./parser');
var parseTag = parser.parseTag;
var parseAttr = parser.parseAttr;
var _ = require('./util');
/**
* 返回值是否为空
*
* @param {Object} obj
* @return {Boolean}
*/
function isNull (obj) {
return (obj === undefined || obj === null);
}
/**
* 取标签内的属性列表字符串
*
* @param {String} html
* @return {Object}
* - {String} html
* - {Boolean} closing
*/
function getAttrs (html) {
var i = html.indexOf(' ');
if (i === -1) {
return {
html: '',
closing: (html[html.length - 2] === '/')
};
}
html = _.trim(html.slice(i + 1, -1));
var isClosing = (html[html.length - 1] === '/');
if (isClosing) html = _.trim(html.slice(0, -1));
return {
html: html,
closing: isClosing
};
}
/**
* 浅拷贝对象
*
* @param {Object} obj
* @return {Object}
*/
function shallowCopyObject (obj) {
var ret = {};
for (var i in obj) {
ret[i] = obj[i];
}
return ret;
}
/**
* XSS过滤对象
*
* @param {Object} options
* 选项whiteList, onTag, onTagAttr, onIgnoreTag,
* onIgnoreTagAttr, safeAttrValue, escapeHtml
* stripIgnoreTagBody, allowCommentTag, stripBlankChar
* css{whiteList, onAttr, onIgnoreAttr} css=false表示禁用cssfilter
*/
function FilterXSS (options) {
options = shallowCopyObject(options || {});
if (options.stripIgnoreTag) {
if (options.onIgnoreTag) {
console.error('Notes: cannot use these two options "stripIgnoreTag" and "onIgnoreTag" at the same time');
}
options.onIgnoreTag = DEFAULT.onIgnoreTagStripAll;
}
options.whiteList = options.whiteList || DEFAULT.whiteList;
options.onTag = options.onTag || DEFAULT.onTag;
options.onTagAttr = options.onTagAttr || DEFAULT.onTagAttr;
options.onIgnoreTag = options.onIgnoreTag || DEFAULT.onIgnoreTag;
options.onIgnoreTagAttr = options.onIgnoreTagAttr || DEFAULT.onIgnoreTagAttr;
options.safeAttrValue = options.safeAttrValue || DEFAULT.safeAttrValue;
options.escapeHtml = options.escapeHtml || DEFAULT.escapeHtml;
this.options = options;
if (options.css === false) {
this.cssFilter = false;
} else {
options.css = options.css || {};
this.cssFilter = new FilterCSS(options.css);
}
}
/**
* 开始处理
*
* @param {String} html
* @return {String}
*/
FilterXSS.prototype.process = function (html) {
// 兼容各种奇葩输入
html = html || '';
html = html.toString();
if (!html) return '';
var me = this;
var options = me.options;
var whiteList = options.whiteList;
var onTag = options.onTag;
var onIgnoreTag = options.onIgnoreTag;
var onTagAttr = options.onTagAttr;
var onIgnoreTagAttr = options.onIgnoreTagAttr;
var safeAttrValue = options.safeAttrValue;
var escapeHtml = options.escapeHtml;
var cssFilter = me.cssFilter;
// 是否清除不可见字符
if (options.stripBlankChar) {
html = DEFAULT.stripBlankChar(html);
}
// 是否禁止备注标签
if (!options.allowCommentTag) {
html = DEFAULT.stripCommentTag(html);
}
// 如果开启了stripIgnoreTagBody
var stripIgnoreTagBody = false;
if (options.stripIgnoreTagBody) {
var stripIgnoreTagBody = DEFAULT.StripTagBody(options.stripIgnoreTagBody, onIgnoreTag);
onIgnoreTag = stripIgnoreTagBody.onIgnoreTag;
}
var retHtml = parseTag(html, function (sourcePosition, position, tag, html, isClosing) {
var info = {
sourcePosition: sourcePosition,
position: position,
isClosing: isClosing,
isWhite: (tag in whiteList)
};
// 调用onTag处理
var ret = onTag(tag, html, info);
if (!isNull(ret)) return ret;
// 默认标签处理方法
if (info.isWhite) {
// 白名单标签,解析标签属性
// 如果是闭合标签,则不需要解析属性
if (info.isClosing) {
return '</' + tag + '>';
}
var attrs = getAttrs(html);
var whiteAttrList = whiteList[tag];
var attrsHtml = parseAttr(attrs.html, function (name, value) {
// 调用onTagAttr处理
var isWhiteAttr = (_.indexOf(whiteAttrList, name) !== -1);
var ret = onTagAttr(tag, name, value, isWhiteAttr);
if (!isNull(ret)) return ret;
// 默认的属性处理方法
if (isWhiteAttr) {
// 白名单属性调用safeAttrValue过滤属性值
value = safeAttrValue(tag, name, value, cssFilter);
if (value) {
return name + '="' + value + '"';
} else {
return name;
}
} else {
// 非白名单属性调用onIgnoreTagAttr处理
var ret = onIgnoreTagAttr(tag, name, value, isWhiteAttr);
if (!isNull(ret)) return ret;
return;
}
});
// 构造新的标签代码
var html = '<' + tag;
if (attrsHtml) html += ' ' + attrsHtml;
if (attrs.closing) html += ' /';
html += '>';
return html;
} else {
// 非白名单标签调用onIgnoreTag处理
var ret = onIgnoreTag(tag, html, info);
if (!isNull(ret)) return ret;
return escapeHtml(html);
}
}, escapeHtml);
// 如果开启了stripIgnoreTagBody需要对结果再进行处理
if (stripIgnoreTagBody) {
retHtml = stripIgnoreTagBody.remove(retHtml);
}
return retHtml;
};
module.exports = FilterXSS;