viewstate를 디코딩하는 방법

viewstate를 디코딩하는 방법

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asp.net 페이지의 viewstate 내용을 봐야합니다. 나는 viewstate 디코더를 찾고 Fridz Onion의 ViewState Decoder를 찾았 지만 viewstate를 얻기 위해 페이지의 URL을 요청합니다. 내 viewstate는 포스트 백 후 형성되고 업데이트 패널의 작업 결과로 제공되므로 URL을 제공 할 수 없습니다. viewstate 문자열을 복사하여 붙여넣고 내부 내용을 확인해야합니다. viewstate의 내용을 보는 데 도움이되는 도구 나 웹 사이트가 있습니까?

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Fiddler를 사용 하고 응답에서보기 상태를 가져 와서 왼쪽 하단 텍스트 상자에 붙여 넣은 다음 디코딩합니다.

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다음은 온라인 ViewState 디코더입니다.

http://ignatu.co.uk/ViewStateDecoder.aspx

편집 : 불행히도 위의 링크는 죽었습니다-여기에 또 다른 ViewState 디코더가 있습니다 (댓글에서).

http://viewstatedecoder.azurewebsites.net/

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다음은 ViewState에 대한 Scott Mitchell의 기사 에서 ViewState 시각화 도우미의 소스 코드입니다 (25 페이지).

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
    }
}

다음은 텍스트 상자에서 viewstate를 읽고 위의 코드를 사용하여 그래프로 표시하는 간단한 페이지입니다.

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();
        }

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다른 사람이 방금 언급했듯이 base64로 인코딩 된 문자열입니다. 과거에는이 웹 사이트를 사용하여 디코딩했습니다.

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

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다음은 2014 년에 잘 작동하는 또 다른 디코더입니다. http://viewstatedecoder.azurewebsites.net/

This worked on an input on which the Ignatu decoder failed with "The serialized data is invalid" (although it leaves the BinaryFormatter-serialized data undecoded, showing only its length).

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JavaScript-ViewState-Parser:

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

The parser should work with most non-encrypted ViewStates. It doesn’t handle the serialization format used by .NET version 1 because that version is sorely outdated and therefore too unlikely to be encountered in any real situation.

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

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Parsing .NET ViewState

• A Spirited Peek into ViewState, Part I:

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

• A Spirited Peek into ViewState, Part II:

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

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This is somewhat "native" .NET way of converting ViewState from string into StateBag Code is below:

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;
    }

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You can ignore the URL field and simply paste the viewstate into the Viewstate string box.

It does look like you have an old version; the serialisation methods changed in ASP.NET 2.0, so grab the 2.0 version

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Online Viewstate Viewer made by Lachlan Keown:

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

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Normally, ViewState should be decryptable if you have the machine-key, right? After all, ASP.net needs to decrypt it, and that is certainly not a black box.

ReferenceURL : https://stackoverflow.com/questions/22814/how-to-decode-viewstate