SignedXml 类

定义

命名空间:

System.Security.Cryptography.Xml

程序集:

System.Security.Cryptography.Xml.dll

包:

System.Security.Cryptography.Xml v11.0.0-preview.4.26230.115

Source:

SignedXml.cs

在核心 XML 签名对象上提供包装器，以帮助创建 XML 签名。

public ref class SignedXml

public class SignedXml

type SignedXml = class

Public Class SignedXml

继承

Object

SignedXml

示例

下面的代码示例演示如何使用信封签名对整个 XML 文档进行签名和验证。

//
// This example signs an XML file using an
// envelope signature. It then verifies the 
// signed XML.
//
using System;
using System.Security.Cryptography;
using System.Security.Cryptography.X509Certificates;
using System.Security.Cryptography.Xml;
using System.Text;
using System.Xml;

public class SignVerifyEnvelope
{

    public static void Main(String[] args)
    {
        try
        {
           // Generate a signing key.
           RSA Key = RSA.Create();

           // Create an XML file to sign.
           CreateSomeXml("Example.xml");
           Console.WriteLine("New XML file created."); 

           // Sign the XML that was just created and save it in a 
           // new file.
           SignXmlFile("Example.xml", "signedExample.xml", Key);
           Console.WriteLine("XML file signed."); 

           // Verify the signature of the signed XML.
           Console.WriteLine("Verifying signature...");
           bool result = VerifyXmlFile("SignedExample.xml", Key);

           // Display the results of the signature verification to 
           // the console.
           if(result)
           {
               Console.WriteLine("The XML signature is valid.");
           }
           else
           {
            Console.WriteLine("The XML signature is not valid.");
           }
        }
        catch(CryptographicException e)
        {
            Console.WriteLine(e.Message);
        }
    }

    // Sign an XML file and save the signature in a new file. This method does not  
    // save the public key within the XML file.  This file cannot be verified unless  
    // the verifying code has the key with which it was signed.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key)
    {
        // Create a new XML document.
        XmlDocument doc = new XmlDocument();

        // Load the passed XML file using its name.
        doc.Load(new XmlTextReader(FileName));

        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml(doc);

        // Add the key to the SignedXml document. 
        signedXml.SigningKey = Key;

        // Create a reference to be signed.
        Reference reference = new Reference();
        reference.Uri = "";

        // Add an enveloped transformation to the reference.
        XmlDsigEnvelopedSignatureTransform env = new XmlDsigEnvelopedSignatureTransform();
        reference.AddTransform(env);

        // Add the reference to the SignedXml object.
        signedXml.AddReference(reference);

        // Compute the signature.
        signedXml.ComputeSignature();

        // Get the XML representation of the signature and save
        // it to an XmlElement object.
        XmlElement xmlDigitalSignature = signedXml.GetXml();

        // Append the element to the XML document.
        doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, true));
        
        if (doc.FirstChild is XmlDeclaration)  
        {
            doc.RemoveChild(doc.FirstChild);
        }

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(SignedFileName, new UTF8Encoding(false));
        doc.WriteTo(xmltw);
        xmltw.Close();
    }

    // Verify the signature of an XML file against an asymmetric 
    // algorithm and return the result.
    public static Boolean VerifyXmlFile(String Name, RSA Key)
    {
        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // Load the passed XML file into the document. 
        xmlDocument.Load(Name);

        // Create a new SignedXml object and pass it
        // the XML document class.
        SignedXml signedXml = new SignedXml(xmlDocument);

        // Find the "Signature" node and create a new
        // XmlNodeList object.
        XmlNodeList nodeList = xmlDocument.GetElementsByTagName("Signature");

        // Load the signature node.
        signedXml.LoadXml((XmlElement)nodeList[0]);

        // Check the signature and return the result.
        return signedXml.CheckSignature(Key);
    }

    // Create example data to sign.
    public static void CreateSomeXml(string FileName)
    {
        // Create a new XmlDocument object.
        XmlDocument document = new XmlDocument();

        // Create a new XmlNode object.
        XmlNode  node = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples");
        
        // Add some text to the node.
        node.InnerText = "Example text to be signed.";

        // Append the node to the document.
        document.AppendChild(node);

        // Save the XML document to the file name specified.
        XmlTextWriter xmltw = new XmlTextWriter(FileName, new UTF8Encoding(false));
        document.WriteTo(xmltw);
        xmltw.Close();
    }
}

'
' This example signs an XML file using an
' envelope signature. It then verifies the 
' signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.X509Certificates
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml



Public Class SignVerifyEnvelope
   
   Overloads Public Shared Sub Main(args() As [String])
      Try
         ' Generate a signing key.
         Dim Key As RSA = RSA.Create()
         
         ' Create an XML file to sign.
         CreateSomeXml("Example.xml")
         Console.WriteLine("New XML file created.")
         
         ' Sign the XML that was just created and save it in a 
         ' new file.
         SignXmlFile("Example.xml", "signedExample.xml", Key)
         Console.WriteLine("XML file signed.")
         
         ' Verify the signature of the signed XML.
         Console.WriteLine("Verifying signature...")
         Dim result As Boolean = VerifyXmlFile("SignedExample.xml", Key)
         
         ' Display the results of the signature verification to 
         ' the console.
         If result Then
            Console.WriteLine("The XML signature is valid.")
         Else
            Console.WriteLine("The XML signature is not valid.")
         End If
      Catch e As CryptographicException
         Console.WriteLine(e.Message)
      End Try
   End Sub 
   
   
   
   ' Sign an XML file and save the signature in a new file. This method does not  
   ' save the public key within the XML file.  This file cannot be verified unless  
   ' the verifying code has the key with which it was signed.
   Public Shared Sub SignXmlFile(FileName As String, SignedFileName As String, Key As RSA)
      ' Create a new XML document.
      Dim doc As New XmlDocument()
      
      ' Load the passed XML file using its name.
      doc.Load(New XmlTextReader(FileName))
      
      ' Create a SignedXml object.
      Dim signedXml As New SignedXml(doc)
      
      ' Add the key to the SignedXml document. 
      signedXml.SigningKey = Key
      
      ' Create a reference to be signed.
      Dim reference As New Reference()
      reference.Uri = ""
      
      ' Add an enveloped transformation to the reference.
      Dim env As New XmlDsigEnvelopedSignatureTransform()
      reference.AddTransform(env)
      
      ' Add the reference to the SignedXml object.
      signedXml.AddReference(reference)
      
      ' Compute the signature.
      signedXml.ComputeSignature()
      
      ' Get the XML representation of the signature and save
      ' it to an XmlElement object.
      Dim xmlDigitalSignature As XmlElement = signedXml.GetXml()
      
      ' Append the element to the XML document.
      doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, True))
      
      If TypeOf doc.FirstChild Is XmlDeclaration Then
         doc.RemoveChild(doc.FirstChild)
      End If
      
      ' Save the signed XML document to a file specified
      ' using the passed string.
      Dim xmltw As New XmlTextWriter(SignedFileName, New UTF8Encoding(False))
      doc.WriteTo(xmltw)
      xmltw.Close()
   End Sub
   
   
   ' Verify the signature of an XML file against an asymmetric 
   ' algorithm and return the result.
   Public Shared Function VerifyXmlFile(Name As [String], Key As RSA) As [Boolean]
      ' Create a new XML document.
      Dim xmlDocument As New XmlDocument()
      
      ' Load the passed XML file into the document. 
      xmlDocument.Load(Name)
      
      ' Create a new SignedXml object and pass it
      ' the XML document class.
      Dim signedXml As New SignedXml(xmlDocument)
      
      ' Find the "Signature" node and create a new
      ' XmlNodeList object.
      Dim nodeList As XmlNodeList = xmlDocument.GetElementsByTagName("Signature")
      
      ' Load the signature node.
      signedXml.LoadXml(CType(nodeList(0), XmlElement))
      
      ' Check the signature and return the result.
      Return signedXml.CheckSignature(Key)
   End Function 
   
   
   
   ' Create example data to sign.
   Public Shared Sub CreateSomeXml(FileName As String)
      ' Create a new XmlDocument object.
      Dim document As New XmlDocument()
      
      ' Create a new XmlNode object.
      Dim node As XmlNode = document.CreateNode(XmlNodeType.Element, "", "MyElement", "samples")
      
      ' Add some text to the node.
      node.InnerText = "Example text to be signed."
      
      ' Append the node to the document.
      document.AppendChild(node)
      
      ' Save the XML document to the file name specified.
      Dim xmltw As New XmlTextWriter(FileName, New UTF8Encoding(False))
      document.WriteTo(xmltw)
      xmltw.Close()
   End Sub 
End Class

下面的代码示例演示如何使用 enveloping 签名对 XML 文档的单个元素进行签名和验证。

//
// This example signs an XML file using an
// envelope signature. It then verifies the
// signed XML.
//
using System;
using System.Security.Cryptography;
using System.Security.Cryptography.Xml;
using System.Text;
using System.Xml;

public class SignVerifyEnvelope
{

    public static void Main(String[] args)
    {
        // Generate a signing key.
       RSA Key = RSA.Create();

       try
       {
           // Specify an element to sign.
           string[] elements =  { "#tag1" };

           // Sign an XML file and save the signature to a
           // new file.
           SignXmlFile("Test.xml", "SignedExample.xml", Key, elements);
           Console.WriteLine("XML file signed.");

           // Verify the signature of the signed XML.
           Console.WriteLine("Verifying signature...");

           bool result = VerifyXmlFile("SignedExample.xml");

           // Display the results of the signature verification to
           // the console.
           if (result)
           {
               Console.WriteLine("The XML signature is valid.");
           }
           else
           {
               Console.WriteLine("The XML signature is not valid.");
           }
       }
       catch (CryptographicException e)
       {
           Console.WriteLine(e.Message);
       }
       finally
       {
           // Clear resources associated with the
           // RSA instance.
           Key.Clear();
       }
   }

    // Sign an XML file and save the signature in a new file.
    public static void SignXmlFile(string FileName, string SignedFileName, RSA Key, string[] ElementsToSign)
    {
        // Check the arguments.
        if (FileName == null)
            throw new ArgumentNullException("FileName");
        if (SignedFileName == null)
            throw new ArgumentNullException("SignedFileName");
        if (Key == null)
            throw new ArgumentNullException("Key");
        if (ElementsToSign == null)
            throw new ArgumentNullException("ElementsToSign");

        // Create a new XML document.
        XmlDocument doc = new XmlDocument();

        // Format the document to ignore white spaces.
        doc.PreserveWhitespace = false;

        // Load the passed XML file using it's name.
        doc.Load(new XmlTextReader(FileName));

        // Create a SignedXml object.
        SignedXml signedXml = new SignedXml(doc);

        // Add the key to the SignedXml document.
        signedXml.SigningKey = Key;

        // Loop through each passed element to sign
        // and create a reference.
        foreach (string s in ElementsToSign)
        {
            // Create a reference to be signed.
            Reference reference = new Reference();
            reference.Uri = s;

            // Add an enveloped transformation to the reference.
            XmlDsigEnvelopedSignatureTransform env = new XmlDsigEnvelopedSignatureTransform();
            reference.AddTransform(env);

            // Add the reference to the SignedXml object.
            signedXml.AddReference(reference);
        }

        // Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
        KeyInfo keyInfo = new KeyInfo();
        keyInfo.AddClause(new RSAKeyValue((RSA)Key));
        signedXml.KeyInfo = keyInfo;

        // Compute the signature.
        signedXml.ComputeSignature();

        // Get the XML representation of the signature and save
        // it to an XmlElement object.
        XmlElement xmlDigitalSignature = signedXml.GetXml();

        // Append the element to the XML document.
        doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, true));

        if (doc.FirstChild is XmlDeclaration)
        {
            doc.RemoveChild(doc.FirstChild);
        }

        // Save the signed XML document to a file specified
        // using the passed string.
        XmlTextWriter xmltw = new XmlTextWriter(SignedFileName, new UTF8Encoding(false));
        doc.WriteTo(xmltw);
        xmltw.Close();
    }
    // Verify the signature of an XML file and return the result.
    public static Boolean VerifyXmlFile(String Name)
    {
        // Check the arguments.
        if (Name == null)
            throw new ArgumentNullException("Name");

        // Create a new XML document.
        XmlDocument xmlDocument = new XmlDocument();

        // Format using white spaces.
        xmlDocument.PreserveWhitespace = true;

        // Load the passed XML file into the document.
        xmlDocument.Load(Name);

        // Create a new SignedXml object and pass it
        // the XML document class.
        SignedXml signedXml = new SignedXml(xmlDocument);

        // Find the "Signature" node and create a new
        // XmlNodeList object.
        XmlNodeList nodeList = xmlDocument.GetElementsByTagName("Signature");

        // Load the signature node.
        signedXml.LoadXml((XmlElement)nodeList[0]);

        // Check the signature and return the result.
        return signedXml.CheckSignature();
    }
}

' This example signs an XML file using an
' envelope signature. It then verifies the 
' signed XML.
'
Imports System.Security.Cryptography
Imports System.Security.Cryptography.Xml
Imports System.Text
Imports System.Xml



Module SignVerifyEnvelope



    Sub Main(ByVal args() As String)
        ' Generate a signing key.
        Dim Key As RSA = RSA.Create()

        Try
            ' Specify an element to sign. 
            Dim elements As String() = New String() {"#tag1"}

            ' Sign an XML file and save the signature to a 
            ' new file.
            SignXmlFile("Test.xml", "SignedExample.xml", Key, elements)
            Console.WriteLine("XML file signed.")

            ' Verify the signature of the signed XML.
            Console.WriteLine("Verifying signature...")

            Dim result As Boolean = VerifyXmlFile("SignedExample.xml")

            ' Display the results of the signature verification to \
            ' the console.
            If result Then
                Console.WriteLine("The XML signature is valid.")
            Else
                Console.WriteLine("The XML signature is not valid.")
            End If
        Catch e As CryptographicException
            Console.WriteLine(e.Message)
        Finally
            ' Clear resources associated with the 
            ' RSA instance.
            Key.Clear()
        End Try

    End Sub


    ' Sign an XML file and save the signature in a new file.
    Sub SignXmlFile(ByVal FileName As String, ByVal SignedFileName As String, ByVal Key As RSA, ByVal ElementsToSign() As String)
        ' Check the arguments.  
        If FileName Is Nothing Then
            Throw New ArgumentNullException("FileName")
        End If
        If SignedFileName Is Nothing Then
            Throw New ArgumentNullException("SignedFileName")
        End If
        If Key Is Nothing Then
            Throw New ArgumentNullException("Key")
        End If
        If ElementsToSign Is Nothing Then
            Throw New ArgumentNullException("ElementsToSign")
        End If
        ' Create a new XML document.
        Dim doc As New XmlDocument()

        ' Format the document to ignore white spaces.
        doc.PreserveWhitespace = False

        ' Load the passed XML file using it's name.
        doc.Load(New XmlTextReader(FileName))

        ' Create a SignedXml object.
        Dim signedXml As New SignedXml(doc)

        ' Add the key to the SignedXml document. 
        signedXml.SigningKey = Key

        ' Loop through each passed element to sign 
        ' and create a reference.
        Dim s As String
        For Each s In ElementsToSign
            ' Create a reference to be signed.
            Dim reference As New Reference()
            reference.Uri = s

            ' Add an enveloped transformation to the reference.
            Dim env As New XmlDsigEnvelopedSignatureTransform()
            reference.AddTransform(env)

            ' Add the reference to the SignedXml object.
            signedXml.AddReference(reference)
        Next s

        ' Add an RSAKeyValue KeyInfo (optional; helps recipient find key to validate).
        Dim keyInfo As New KeyInfo()
        keyInfo.AddClause(New RSAKeyValue(CType(Key, RSA)))
        signedXml.KeyInfo = keyInfo

        ' Compute the signature.
        signedXml.ComputeSignature()

        ' Get the XML representation of the signature and save
        ' it to an XmlElement object.
        Dim xmlDigitalSignature As XmlElement = signedXml.GetXml()

        ' Append the element to the XML document.
        doc.DocumentElement.AppendChild(doc.ImportNode(xmlDigitalSignature, True))


        If TypeOf doc.FirstChild Is XmlDeclaration Then
            doc.RemoveChild(doc.FirstChild)
        End If

        ' Save the signed XML document to a file specified
        ' using the passed string.
        Dim xmltw As New XmlTextWriter(SignedFileName, New UTF8Encoding(False))
        doc.WriteTo(xmltw)
        xmltw.Close()

    End Sub

    ' Verify the signature of an XML file and return the result.
    Function VerifyXmlFile(ByVal Name As String) As [Boolean]
        ' Check the arguments.  
        If Name Is Nothing Then
            Throw New ArgumentNullException("Name")
        End If
        ' Create a new XML document.
        Dim xmlDocument As New XmlDocument()

        ' Format using white spaces.
        xmlDocument.PreserveWhitespace = True

        ' Load the passed XML file into the document. 
        xmlDocument.Load(Name)

        ' Create a new SignedXml object and pass it
        ' the XML document class.
        Dim signedXml As New SignedXml(xmlDocument)

        ' Find the "Signature" node and create a new
        ' XmlNodeList object.
        Dim nodeList As XmlNodeList = xmlDocument.GetElementsByTagName("Signature")

        ' Load the signature node.
        signedXml.LoadXml(CType(nodeList(0), XmlElement))

        ' Check the signature and return the result.
        Return signedXml.CheckSignature()

    End Function
End Module

注解

有关此 API 的详细信息，请参阅 SignedXml 的补充 API 备注。

构造函数

名称	说明
SignedXml()	初始化 SignedXml 类的新实例。
SignedXml(XmlDocument)	从指定的 XML 文档初始化类的新实例 SignedXml 。
SignedXml(XmlElement)	从指定SignedXml对象初始化类的新实例XmlElement。

字段

名称	说明
m_signature	表示 Signature 当前 SignedXml 对象的对象。
m_strSigningKeyName	表示要用于对对象进行签名的 SignedXml 已安装密钥的名称。
XmlDecryptionTransformUrl	表示 XML 模式解密转换的统一资源标识符（URI）。 此字段为常量。
XmlDsigBase64TransformUrl	表示 base 64 转换的统一资源标识符（URI）。 此字段为常量。
XmlDsigC14NTransformUrl	表示规范 XML 转换的统一资源标识符（URI）。 此字段为常量。
XmlDsigC14NWithCommentsTransformUrl	表示规范 XML 转换的统一资源标识符（URI），带有注释。 此字段为常量。
XmlDsigCanonicalizationUrl	表示 XML 数字签名的标准规范化算法的统一资源标识符（URI）。 此字段为常量。
XmlDsigCanonicalizationWithCommentsUrl	表示 XML 数字签名的标准规范化算法的统一资源标识符（URI），并包括注释。 此字段为常量。
XmlDsigDSAUrl	表示 XML 数字签名的标准 DSA 算法的统一资源标识符（URI）。 此字段为常量。
XmlDsigEnvelopedSignatureTransformUrl	表示信封签名转换的统一资源标识符（URI）。 此字段为常量。
XmlDsigExcC14NTransformUrl	表示独占 XML 规范化的统一资源标识符（URI）。 此字段为常量。
XmlDsigExcC14NWithCommentsTransformUrl	表示具有注释的独占 XML 规范化的统一资源标识符（URI）。 此字段为常量。
XmlDsigHMACSHA1Url	表示 XML 数字签名的标准 HMACSHA1 算法的统一资源标识符（URI）。 此字段为常量。
XmlDsigMinimalCanonicalizationUrl	表示 XML 数字签名的标准最小规范化算法的统一资源标识符（URI）。 此字段为常量。
XmlDsigNamespaceUrl	表示 XML 数字签名的标准命名空间的统一资源标识符（URI）。 此字段为常量。
XmlDsigRSASHA1Url	表示 XML 数字签名的标准 RSA 签名方法的统一资源标识符（URI）。 此字段为常量。
XmlDsigRSASHA256Url	表示 XML 数字签名的 SHA-256 签名方法变体的 RSA 统一资源标识符（URI）。 此字段为常量。
XmlDsigRSASHA384Url	表示 XML 数字签名的 SHA-384 签名方法变体的 RSA 统一资源标识符（URI）。 此字段为常量。
XmlDsigRSASHA512Url	表示 XML 数字签名的 SHA-512 签名方法变体的 RSA 统一资源标识符（URI）。 此字段为常量。
XmlDsigSHA1Url	表示 XML 数字签名的标准 SHA1 摘要方法的统一资源标识符（URI）。 此字段为常量。
XmlDsigSHA256Url	表示 XML 数字签名的标准 SHA256 摘要方法的统一资源标识符（URI）。 此字段为常量。
XmlDsigSHA384Url	表示 XML 数字签名的标准 SHA384 摘要方法的统一资源标识符（URI）。 此字段为常量。
XmlDsigSHA512Url	表示 XML 数字签名的标准 SHA512 摘要方法的统一资源标识符（URI）。 此字段为常量。
XmlDsigXPathTransformUrl	表示 XML 路径语言（XPath）的统一资源标识符（URI）。 此字段为常量。
XmlDsigXsltTransformUrl	表示 XSLT 转换的统一资源标识符（URI）。 此字段为常量。
XmlLicenseTransformUrl	表示用于规范签名的 XrML 许可证的许可证转换算法的统一资源标识符（URI）。

属性

名称	说明
EncryptedXml	获取或设置定义 EncryptedXml XML 加密处理规则的对象。
KeyInfo	获取或设置 KeyInfo 当前 SignedXml 对象的对象。
Resolver	设置当前 XmlResolver 对象。
SafeCanonicalizationMethods	获取显式允许其规范化算法的方法的名称。
Signature	Signature获取当前SignedXml对象的对象。
SignatureFormatValidator	获取将调用以验证 XML 签名的格式（而不是加密安全性）的委托。
SignatureLength	获取当前 SignedXml 对象的签名长度。
SignatureMethod	获取当前 SignedXml 对象的签名方法。
SignatureValue	获取当前 SignedXml 对象的签名值。
SignedInfo	SignedInfo获取当前SignedXml对象的对象。
SigningKey	获取或设置用于对对象进行签名 SignedXml 的非对称算法密钥。
SigningKeyName	获取或设置要用于对对象进行签名的 SignedXml 已安装密钥的名称。

方法

名称	说明
AddObject(DataObject)	将对象 DataObject 添加到要签名的对象列表中。
AddReference(Reference)	将对象 Reference 添加到 SignedXml 描述摘要方法、摘要值和转换的对象，以用于创建 XML 数字签名。
CheckSignature()	确定属性是否 Signature 使用签名中的公钥进行验证。
CheckSignature(AsymmetricAlgorithm)	确定属性是否 Signature 验证指定的键。
CheckSignature(KeyedHashAlgorithm)	确定属性是否 Signature 验证指定的消息身份验证代码 （MAC） 算法。
CheckSignature(X509Certificate2, Boolean)	确定属性是否 Signature 对指定 X509Certificate2 对象进行验证，以及证书是否有效（可选）。
CheckSignatureReturningKey(AsymmetricAlgorithm)	确定属性是否 Signature 使用签名中的公钥进行验证。
ComputeSignature()	计算 XML 数字签名。
ComputeSignature(KeyedHashAlgorithm)	使用指定的消息身份验证代码（MAC）算法计算 XML 数字签名。
GetIdElement(XmlDocument, String)	从 XmlElement 指定对象返回具有指定 XmlDocument ID 的对象。
GetPublicKey()	返回签名的公钥。
GetXml()	返回对象的 XML 表示形式 SignedXml 。
LoadXml(XmlElement)	SignedXml从 XML 元素加载状态。

另请参阅

• XML 签名最佳做法