Esempio n. 1
0
        private static TagValid checkTagValid(Match m, List <String> tobeClearTags, Dictionary <String, String> whitelist)
        {
            String tag = m.Value;

            TagValid isComment = checkHtmlComment(tag);

            if (isComment.IsValid)
            {
                return(isComment);
            }

            String endTagName = getEndTagName(tag);

            if (strUtil.HasText(endTagName))
            {
                TagValid v = checkEndTag(endTagName, tobeClearTags, whitelist);
                v.IsStartTag = false;
                return(v);
            }

            TagValid result = checkStartTag(tag, whitelist);

            result.IsStartTag = true;
            return(result);
        }
Esempio n. 2
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        private static String Clear(String input, Dictionary <String, String> whitelist)
        {
            MatchCollection ms = getMatchs(input);

            StringBuilder sb = new StringBuilder();

            int lastIndex = 0;

            List <String> tobeClearTags = new List <String>();

            foreach (Match m in ms)
            {
                TagValid validResult = checkTagValid(m, tobeClearTags, whitelist);
                sb.Append(input.Substring(lastIndex, m.Index - lastIndex));

                if (validResult.IsValid)
                {
                    sb.Append(input.Substring(m.Index, m.Length));
                }
                else
                {
                    if (validResult.IsStartTag)
                    {
                        tobeClearTags.Add(validResult.Name);
                    }
                }

                lastIndex = m.Index + m.Length;
            }
            sb.Append(input.Substring(lastIndex, input.Length - lastIndex));

            return(sb.ToString());
        }
Esempio n. 3
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        private static TagValid checkHtmlComment( string tag )
        {
            TagValid v = new TagValid();
            v.IsValid = true;
            if (strUtil.IsNullOrEmpty( tag )) return v;
            if (tag.StartsWith( "<!--" ) && tag.EndsWith( "-->" )) return v;

            v.IsValid = false;
            return v;
        }
Esempio n. 4
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        private static TagValid checkEndTag( String tagName, List<String> tobeClearTags, Dictionary<String, String> whitelist )
        {
            TagValid result = new TagValid( tagName );

            foreach (String tobeTag in tobeClearTags) {
                if (tobeTag.Equals( tagName )) {
                    tobeClearTags.Remove( tobeTag );
                    result.IsValid = false;
                    return result;
                }
            }

            result.IsValid = whitelist.ContainsKey( tagName );
            return result;
        }
Esempio n. 5
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        private static TagValid checkEndTag(String tagName, List <String> tobeClearTags, Dictionary <String, String> whitelist)
        {
            TagValid result = new TagValid(tagName);

            foreach (String tobeTag in tobeClearTags)
            {
                if (tobeTag.Equals(tagName))
                {
                    tobeClearTags.Remove(tobeTag);
                    result.IsValid = false;
                    return(result);
                }
            }

            result.IsValid = whitelist.ContainsKey(tagName.ToLower());
            return(result);
        }
Esempio n. 6
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        private static TagValid checkHtmlComment(string tag)
        {
            TagValid v = new TagValid();

            v.IsValid = true;
            if (strUtil.IsNullOrEmpty(tag))
            {
                return(v);
            }
            if (tag.StartsWith("<!--") && tag.EndsWith("-->"))
            {
                return(v);
            }

            v.IsValid = false;
            return(v);
        }
Esempio n. 7
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        /// <summary>
        /// 根据白名单过滤
        /// </summary>
        /// <param name="input">需要过滤的字符串</param>
        /// <param name="whitelist">白名单</param>
        /// <param name="isAddBaseAttr">是否允许 id/class/style 这三个基础属性</param>
        /// <returns></returns>
        public static String Clear(String input, Dictionary <String, String> whitelist, Boolean isAddBaseAttr)
        {
            input = clearScriptContent(input, whitelist);

            MatchCollection ms = getMatchs(input);

            StringBuilder sb = new StringBuilder();

            int lastIndex = 0;

            List <String> tobeClearTags = new List <String>();

            foreach (Match m in ms)
            {
                TagValid validResult = checkTagValid(m, tobeClearTags, whitelist);
                sb.Append(input.Substring(lastIndex, m.Index - lastIndex));

                if (validResult.IsValid)
                {
                    if (validResult.IsStartTag)
                    {
                        addTagAndAttribute(input, sb, m, whitelist, isAddBaseAttr);
                    }
                    else
                    {
                        addTagString(input, sb, m);
                    }
                }
                else
                {
                    if (validResult.IsStartTag)
                    {
                        tobeClearTags.Add(validResult.Name);
                    }
                }

                lastIndex = m.Index + m.Length;
            }
            sb.Append(input.Substring(lastIndex, input.Length - lastIndex));

            return(sb.ToString());
        }