如何解码viewstate

Question

我需要查看asp.net页面的viewstate的内容。我找了一个viewstate解码器，发现Fridz Onion's ViewState Decoder但它要求页面的url获取其viewstate。由于我的视图状态是在回发之后形成的，并且是由于更新面板中的操作而导致的，因此我无法提供网址。我需要复制＆amp;粘贴viewstate字符串，看看里面是什么。是否存在可以帮助查看viewstate内容的工具或网站？

Answer 1

这是一个在线ViewState解码器：

<击> http://ignatu.co.uk/ViewStateDecoder.aspx

编辑：不幸的是，上面的链接已经死了 - 这是另一个ViewState解码器（来自评论）：

http://viewstatedecoder.azurewebsites.net/

Answer 2

使用Fiddler并抓取响应中的视图状态并将其粘贴到左下方文本框中，然后解码。

Answer 3

以下是来自Scott Mitchell's article on ViewState（25页）

的ViewState可视化工具的源代码

using System;
using System.Collections;
using System.Text;
using System.IO;
using System.Web.UI;


namespace ViewStateArticle.ExtendedPageClasses
{
    /// <summary>
    /// Parses the view state, constructing a viaully-accessible object graph.
    /// </summary>
    public class ViewStateParser
    {
        // private member variables
        private TextWriter tw;
        private string indentString = "   ";

        #region Constructor
        /// <summary>
        /// Creates a new ViewStateParser instance, specifying the TextWriter to emit the output to.
        /// </summary>
        public ViewStateParser(TextWriter writer)
        {
            tw = writer;
        }
        #endregion

        #region Methods
        #region ParseViewStateGraph Methods
        /// <summary>
        /// Emits a readable version of the view state to the TextWriter passed into the object's constructor.
        /// </summary>
        /// <param name="viewState">The view state object to start parsing at.</param>
        public virtual void ParseViewStateGraph(object viewState)
        {
            ParseViewStateGraph(viewState, 0, string.Empty);    
        }

        /// <summary>
        /// Emits a readable version of the view state to the TextWriter passed into the object's constructor.
        /// </summary>
        /// <param name="viewStateAsString">A base-64 encoded representation of the view state to parse.</param>
        public virtual void ParseViewStateGraph(string viewStateAsString)
        {
            // First, deserialize the string into a Triplet
            LosFormatter los = new LosFormatter();
            object viewState = los.Deserialize(viewStateAsString);

            ParseViewStateGraph(viewState, 0, string.Empty);    
        }

        /// <summary>
        /// Recursively parses the view state.
        /// </summary>
        /// <param name="node">The current view state node.</param>
        /// <param name="depth">The "depth" of the view state tree.</param>
        /// <param name="label">A label to display in the emitted output next to the current node.</param>
        protected virtual void ParseViewStateGraph(object node, int depth, string label)
        {
            tw.Write(System.Environment.NewLine);

            if (node == null)
            {
                tw.Write(String.Concat(Indent(depth), label, "NODE IS NULL"));
            } 
            else if (node is Triplet)
            {
                tw.Write(String.Concat(Indent(depth), label, "TRIPLET"));
                ParseViewStateGraph(((Triplet) node).First, depth+1, "First: ");
                ParseViewStateGraph(((Triplet) node).Second, depth+1, "Second: ");
                ParseViewStateGraph(((Triplet) node).Third, depth+1, "Third: ");
            }
            else if (node is Pair)
            {
                tw.Write(String.Concat(Indent(depth), label, "PAIR"));
                ParseViewStateGraph(((Pair) node).First, depth+1, "First: ");
                ParseViewStateGraph(((Pair) node).Second, depth+1, "Second: ");
            }
            else if (node is ArrayList)
            {
                tw.Write(String.Concat(Indent(depth), label, "ARRAYLIST"));

                // display array values
                for (int i = 0; i < ((ArrayList) node).Count; i++)
                    ParseViewStateGraph(((ArrayList) node)[i], depth+1, String.Format("({0}) ", i));
            }
            else if (node.GetType().IsArray)
            {
                tw.Write(String.Concat(Indent(depth), label, "ARRAY "));
                tw.Write(String.Concat("(", node.GetType().ToString(), ")"));
                IEnumerator e = ((Array) node).GetEnumerator();
                int count = 0;
                while (e.MoveNext())
                    ParseViewStateGraph(e.Current, depth+1, String.Format("({0}) ", count++));
            }
            else if (node.GetType().IsPrimitive || node is string)
            {
                tw.Write(String.Concat(Indent(depth), label));
                tw.Write(node.ToString() + " (" + node.GetType().ToString() + ")");
            }
            else
            {
                tw.Write(String.Concat(Indent(depth), label, "OTHER - "));
                tw.Write(node.GetType().ToString());
            }
        }
        #endregion

        /// <summary>
        /// Returns a string containing the <see cref="IndentString"/> property value a specified number of times.
        /// </summary>
        /// <param name="depth">The number of times to repeat the <see cref="IndentString"/> property.</param>
        /// <returns>A string containing the <see cref="IndentString"/> property value a specified number of times.</returns>
        protected virtual string Indent(int depth)
        {
            StringBuilder sb = new StringBuilder(IndentString.Length * depth);
            for (int i = 0; i < depth; i++)
                sb.Append(IndentString);

            return sb.ToString();
        }
        #endregion

        #region Properties
        /// <summary>
        /// Specifies the indentation to use for each level when displaying the object graph.
        /// </summary>
        /// <value>A string value; the default is three blank spaces.</value>
        public string IndentString
        {
            get
            {
                return indentString;
            }
            set
            {
                indentString = value;
            }
        }
        #endregion
    }
}

这是一个简单的页面，可以从文本框中读取视图状态，并使用上面的代码对其进行绘图

private void btnParse_Click(object sender, System.EventArgs e)
        {
            // parse the viewState
            StringWriter writer = new StringWriter();
            ViewStateParser p = new ViewStateParser(writer);

            p.ParseViewStateGraph(txtViewState.Text);
            ltlViewState.Text = writer.ToString();
        }

Answer 4

正如刚才提到的另一个人，它是一个base64编码的字符串。在过去，我使用这个网站解码它：

http://www.motobit.com/util/base64-decoder-encoder.asp

Answer 5

这是另一个在2014年运作良好的解码器：http://viewstatedecoder.azurewebsites.net/

这适用于Ignatu解码器失败的输入＆＃34;序列化数据无效＆＃34; （虽然它使BinaryFormatter序列化数据未解码，仅显示其长度）。

Answer 6

JavaScript的视图状态分析器：

• http://mutantzombie.github.com/JavaScript-ViewState-Parser/
• https://github.com/mutantzombie/JavaScript-ViewState-Parser/

  

解析器应该与大多数未加密的ViewStates一起使用。它没有   处理.NET版本1使用的序列化格式，因为它   版本已经过时了，因此太不可能了   遇到任何实际情况。

http://deadliestwebattacks.com/2011/05/29/javascript-viewstate-parser/

---

解析.NET ViewState

• 窥探ViewState，第一部分：

  http://deadliestwebattacks.com/2011/05/13/a-spirited-peek-into-viewstate-part-i/

• 窥探ViewState，第二部分：

  http://deadliestwebattacks.com/2011/05/25/a-spirited-peek-into-viewstate-part-ii/

---

Answer 7

您可以忽略URL字段，只需将视图状态粘贴到Viewstate字符串框中即可。

看起来你有一个旧版本;在ASP.NET 2.0中更改了序列化方法，因此请抓取2.0 version

Answer 8

这是将ViewState从字符串转换为StateBag的某种“原生”.NET方式 代码如下：

public static StateBag LoadViewState(string viewState)
    {
        System.Web.UI.Page converterPage = new System.Web.UI.Page();
        HiddenFieldPageStatePersister persister = new HiddenFieldPageStatePersister(new Page());
        Type utilClass = typeof(System.Web.UI.BaseParser).Assembly.GetType("System.Web.UI.Util");
        if (utilClass != null && persister != null)
        {
            MethodInfo method = utilClass.GetMethod("DeserializeWithAssert", BindingFlags.NonPublic | BindingFlags.Static);
            if (method != null)
            {
                PropertyInfo formatterProperty = persister.GetType().GetProperty("StateFormatter", BindingFlags.NonPublic | BindingFlags.Instance);
                if (formatterProperty != null)
                {
                    IStateFormatter formatter = (IStateFormatter)formatterProperty.GetValue(persister, null);
                    if (formatter != null)
                    {
                        FieldInfo pageField = formatter.GetType().GetField("_page", BindingFlags.NonPublic | BindingFlags.Instance);
                        if (pageField != null)
                        {
                            pageField.SetValue(formatter, null);
                            try
                            {
                                Pair pair = (Pair)method.Invoke(null, new object[] { formatter, viewState });
                                if (pair != null)
                                {
                                    MethodInfo loadViewState = converterPage.GetType().GetMethod("LoadViewStateRecursive", BindingFlags.Instance | BindingFlags.NonPublic);
                                    if (loadViewState != null)
                                    {
                                        FieldInfo postback = converterPage.GetType().GetField("_isCrossPagePostBack", BindingFlags.NonPublic | BindingFlags.Instance);
                                        if (postback != null)
                                        {
                                            postback.SetValue(converterPage, true);
                                        }
                                        FieldInfo namevalue = converterPage.GetType().GetField("_requestValueCollection", BindingFlags.NonPublic | BindingFlags.Instance);
                                        if (namevalue != null)
                                        {
                                            namevalue.SetValue(converterPage, new NameValueCollection());
                                        }
                                        loadViewState.Invoke(converterPage, new object[] { ((Pair)((Pair)pair.First).Second) });
                                        FieldInfo viewStateField = typeof(Control).GetField("_viewState", BindingFlags.NonPublic | BindingFlags.Instance);
                                        if (viewStateField != null)
                                        {
                                            return (StateBag)viewStateField.GetValue(converterPage);
                                        }
                                    }
                                }
                            }
                            catch (Exception ex)
                            {
                                if (ex != null)
                                {

                                }
                            }
                        }
                    }
                }
            }
        }
        return null;
    }

Answer 9

Lachlan Keown制作的在线Viewstate Viewer：

http://lachlankeown.blogspot.com/2008/05/online-viewstate-viewer-decoder.html

Answer 10

通常情况下，如果你有机器密钥，ViewState应该是可解密的，对吧？毕竟，ASP.net需要解密它，这当然不是黑盒子。

Answer 11

Python中最好的方法是使用此link。

一个小的Python 3.5+库，用于解码ASP.NET视图状态。

首先安装：pip install viewstate

>>> from viewstate import ViewState
>>> base64_encoded_viewstate = '/wEPBQVhYmNkZQ9nAgE='
>>> vs = ViewState(base64_encoded_viewstate)
>>> vs.decode()
('abcde', (True, 1))