CA2312：确保在反序列化之前设置 NetDataContractSerializer.Binder

  • 项目
属性 值
规则 ID CA2312
标题 确保在反序列化之前设置 NetDataContractSerializer.Binder
类别 安全性
修复是中断修复还是非中断修复 非中断
在 .NET 8 中默认启用 否

原因

调用或引用了 System.Runtime.Serialization.NetDataContractSerializer 反序列化方法，但 Binder 属性可能为 NULL。

此规则类似于 CA2311，但无法通过分析确定 Binder 是否肯定为 NULL。

默认情况下，此规则会分析整个代码库，但这是可配置的。

警告

使用 SerializationBinder 限制类型无法阻止所有攻击。 有关详细信息，请参阅 BinaryFormatter 安全指南。

规则说明

反序列化不受信任的数据时，会对不安全的反序列化程序造成风险。 攻击者可能会修改序列化数据，使其包含非预期类型，进而注入具有不良副作用的对象。 例如，针对不安全反序列化程序的攻击可以在基础操作系统上执行命令，通过网络进行通信，或删除文件。

此规则会在 Binder 可能为 NULL 时查找 System.Runtime.Serialization.NetDataContractSerializer 反序列化方法调用或引用。 无论 Binder 属性如何，如果要使用 NetDataContractSerializer 禁止任何反序列化，请禁用此规则和 CA2311，并启用规则 CA2310。

NetDataContractSerializer 不安全，无法确保安全。 有关详细信息，请参阅 BinaryFormatter 安全指南。

如何解决冲突

  • 改用安全的序列化程序，并且不允许攻击者指定要反序列化的任意类型。 有关详细信息，请参阅首选替代方案。
  • 使序列化的数据免被篡改。 序列化后，对序列化的数据进行加密签名。 在反序列化之前，验证加密签名。 保护加密密钥不被泄露，并针对密钥轮换进行设计。
  • 此选项使代码容易遭受拒绝服务攻击，以及将来可能会发生的远程代码执行攻击。 有关详细信息，请参阅 BinaryFormatter 安全指南。 限制反序列化的类型。 实现自定义 System.Runtime.Serialization.SerializationBinder。 在反序列化之前，请在所有代码路径中将 Binder 属性设置为自定义 SerializationBinder 的实例。 在替代的 BindToType 方法中，如果类型不是预期类型，将引发异常以停止反序列化。

何时禁止显示警告

NetDataContractSerializer 不安全，无法确保安全。

配置代码以进行分析

使用下面的选项来配置代码库的哪些部分要运行此规则。

可以仅为此规则、为适用的所有规则或为适用的此类别（安全性）中的所有规则配置这些选项。 有关详细信息，请参阅代码质量规则配置选项。

排除特定符号

可以从分析中排除特定符号，如类型和方法。 例如，若要指定规则不应针对名为 MyType 的类型中的任何代码运行，请将以下键值对添加到项目中的 .editorconfig 文件：

dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType

选项值中允许的符号名称格式（用 | 分隔）：

  • 仅符号名称（包括具有相应名称的所有符号，不考虑包含的类型或命名空间）。
  • 完全限定的名称，使用符号的文档 ID 格式。 每个符号名称都需要带有一个符号类型前缀，例如表示方法的 M:、表示类型的 T:，以及表示命名空间的 N:。
  • .ctor 表示构造函数，.cctor 表示静态构造函数。

示例：

选项值 总结
dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType 匹配名为 MyType 的所有符号。
dotnet_code_quality.CAXXXX.excluded_symbol_names = MyType1|MyType2 匹配名为 MyType1 或 MyType2 的所有符号。
dotnet_code_quality.CAXXXX.excluded_symbol_names = M:NS.MyType.MyMethod(ParamType) 匹配带有指定的完全限定签名的特定方法 MyMethod。
dotnet_code_quality.CAXXXX.excluded_symbol_names = M:NS1.MyType1.MyMethod1(ParamType)|M:NS2.MyType2.MyMethod2(ParamType) 匹配带有各自的完全限定签名的特定方法 MyMethod1 和 MyMethod2。

排除特定类型及其派生类型

可以从分析中排除特定类型及其派生类型。 例如，若要指定规则不应针对名为 MyType 的类型及其派生类型中的任何代码运行，请将以下键值对添加到项目中的 .editorconfig 文件：

dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType

选项值中允许的符号名称格式（用 | 分隔）：

  • 仅类型名称（包括具有相应名称的所有类型，不考虑包含的类型或命名空间）。
  • 完全限定的名称，使用符号的文档 ID 格式，前缀为 T:（可选）。

示例：

选项值 总结
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType 匹配名为 MyType 的所有类型及其所有派生类型。
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = MyType1|MyType2 匹配名为 MyType1 或 MyType2 的所有类型及其所有派生类型。
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = M:NS.MyType 匹配带有给定的完全限定名称的特定类型 MyType 及其所有派生类型。
dotnet_code_quality.CAXXXX.excluded_type_names_with_derived_types = M:NS1.MyType1|M:NS2.MyType2 匹配带有各自的完全限定名称的特定类型 MyType1 和 MyType2 及其所有派生类型。

伪代码示例

冲突 1

using System;
using System.IO;
using System.Runtime.Serialization;

public class BookRecordSerializationBinder : SerializationBinder
{
    public override Type BindToType(string assemblyName, string typeName)
    {
        // One way to discover expected types is through testing deserialization
        // of **valid** data and logging the types used.

        ////Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')");

        if (typeName == "BookRecord")
        {
            return typeof(BookRecord);
        }
        else if (typeName == "AisleLocation")
        {
            return typeof(AisleLocation);
        }
        else
        {
            throw new ArgumentException("Unexpected type", nameof(typeName));
        }
    }
}

[DataContract]
public class BookRecord
{
    [DataMember]
    public string Title { get; set; }

    [DataMember]
    public AisleLocation Location { get; set; }
}

[DataContract]
public class AisleLocation
{
    [DataMember]
    public char Aisle { get; set; }

    [DataMember]
    public byte Shelf { get; set; }
}

public class Binders
{
    public static SerializationBinder BookRecord = new BookRecordSerializationBinder();
}

public class ExampleClass
{
    public BookRecord DeserializeBookRecord(byte[] bytes)
    {
        NetDataContractSerializer serializer = new NetDataContractSerializer();
        serializer.Binder = Binders.BookRecord;
        using (MemoryStream ms = new MemoryStream(bytes))
        {
            return (BookRecord) serializer.Deserialize(ms);
        }
    }
}

Imports System
Imports System.IO
Imports System.Runtime.Serialization

Public Class BookRecordSerializationBinder
    Inherits SerializationBinder

    Public Overrides Function BindToType(assemblyName As String, typeName As String) As Type
        ' One way to discover expected types is through testing deserialization
        ' of **valid** data and logging the types used.

        'Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')")

        If typeName = "BinaryFormatterVB.BookRecord" Then
            Return GetType(BookRecord)
        Else If typeName = "BinaryFormatterVB.AisleLocation" Then
            Return GetType(AisleLocation)
        Else
            Throw New ArgumentException("Unexpected type", NameOf(typeName))
        End If
    End Function
End Class

<DataContract()>
Public Class BookRecord
    <DataMember()>
    Public Property Title As String

    <DataMember()>
    Public Property Location As AisleLocation
End Class

<DataContract()>
Public Class AisleLocation
    <DataMember()>
    Public Property Aisle As Char

    <DataMember()>
    Public Property Shelf As Byte
End Class

Public Class Binders
    Public Shared Property BookRecord As SerializationBinder = New BookRecordSerializationBinder()
End Class


Public Class ExampleClass
    Public Function DeserializeBookRecord(bytes As Byte()) As BookRecord
        Dim serializer As NetDataContractSerializer = New NetDataContractSerializer()
        serializer.Binder = Binders.BookRecord
        Using ms As MemoryStream = New MemoryStream(bytes)
            Return CType(serializer.Deserialize(ms), BookRecord)   ' CA2312 violation
        End Using
    End Function
End Class

解决方案 1

using System;
using System.IO;
using System.Runtime.Serialization;

public class BookRecordSerializationBinder : SerializationBinder
{
    public override Type BindToType(string assemblyName, string typeName)
    {
        // One way to discover expected types is through testing deserialization
        // of **valid** data and logging the types used.

        ////Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')");

        if (typeName == "BookRecord")
        {
            return typeof(BookRecord);
        }
        else if (typeName == "AisleLocation")
        {
            return typeof(AisleLocation);
        }
        else
        {
            throw new ArgumentException("Unexpected type", nameof(typeName));
        }
    }
}

[DataContract]
public class BookRecord
{
    [DataMember]
    public string Title { get; set; }

    [DataMember]
    public AisleLocation Location { get; set; }
}

[DataContract]
public class AisleLocation
{
    [DataMember]
    public char Aisle { get; set; }

    [DataMember]
    public byte Shelf { get; set; }
}

public class Binders
{
    public static SerializationBinder BookRecord = new BookRecordSerializationBinder();
}

public class ExampleClass
{
    public BookRecord DeserializeBookRecord(byte[] bytes)
    {
        NetDataContractSerializer serializer = new NetDataContractSerializer();

        // Ensure that Binder is always non-null before deserializing
        serializer.Binder = Binders.BookRecord ?? throw new Exception("Expected non-null");

        using (MemoryStream ms = new MemoryStream(bytes))
        {
            return (BookRecord) serializer.Deserialize(ms);
        }
    }
}

Imports System
Imports System.IO
Imports System.Runtime.Serialization

Public Class BookRecordSerializationBinder
    Inherits SerializationBinder

    Public Overrides Function BindToType(assemblyName As String, typeName As String) As Type
        ' One way to discover expected types is through testing deserialization
        ' of **valid** data and logging the types used.

        'Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')")

        If typeName = "BinaryFormatterVB.BookRecord" Then
            Return GetType(BookRecord)
        Else If typeName = "BinaryFormatterVB.AisleLocation" Then
            Return GetType(AisleLocation)
        Else
            Throw New ArgumentException("Unexpected type", NameOf(typeName))
        End If
    End Function
End Class

<DataContract()>
Public Class BookRecord
    <DataMember()>
    Public Property Title As String

    <DataMember()>
    Public Property Location As AisleLocation
End Class

<DataContract()>
Public Class AisleLocation
    <DataMember()>
    Public Property Aisle As Char

    <DataMember()>
    Public Property Shelf As Byte
End Class

Public Class Binders
    Public Shared Property BookRecord As SerializationBinder = New BookRecordSerializationBinder()
End Class


Public Class ExampleClass
    Public Function DeserializeBookRecord(bytes As Byte()) As BookRecord
        Dim serializer As NetDataContractSerializer = New NetDataContractSerializer()

        ' Ensure that Binder is always non-null before deserializing
        serializer.Binder = If(Binders.BookRecord, New Exception("Expected non-null"))

        Using ms As MemoryStream = New MemoryStream(bytes)
            Return CType(serializer.Deserialize(ms), BookRecord)
        End Using
    End Function
End Class

冲突 2

using System;
using System.IO;
using System.Runtime.Serialization;

[DataContract]
public class BookRecord
{
    [DataMember]
    public string Title { get; set; }

    [DataMember]
    public string Author { get; set; }

    [DataMember]
    public int PageCount { get; set; }

    [DataMember]
    public AisleLocation Location { get; set; }
}

[DataContract]
public class AisleLocation
{
    [DataMember]
    public char Aisle { get; set; }

    [DataMember]
    public byte Shelf { get; set; }
}

public class ExampleClass
{
    public NetDataContractSerializer Serializer { get; set; }

    public BookRecord DeserializeBookRecord(byte[] bytes)
    {
        using (MemoryStream ms = new MemoryStream(bytes))
        {
            return (BookRecord) this.Serializer.Deserialize(ms);    // CA2312 violation
        }
    }
}

Imports System
Imports System.IO
Imports System.Runtime.Serialization

<DataContract()>
Public Class BookRecord
    <DataMember()>
    Public Property Title As String

    <DataMember()>
    Public Property Author As String

    <DataMember()>
    Public Property Location As AisleLocation
End Class

<DataContract()>
Public Class AisleLocation
    <DataMember()>
    Public Property Aisle As Char

    <DataMember()>
    Public Property Shelf As Byte
End Class

Public Class ExampleClass
    Public Property Serializer As NetDataContractSerializer

    Public Function DeserializeBookRecord(bytes As Byte()) As BookRecord
        Using ms As MemoryStream = New MemoryStream(bytes)
            Return CType(Me.Serializer.Deserialize(ms), BookRecord)    ' CA2312 violation
        End Using
    End Function
End Class

解决方案 2

using System;
using System.IO;
using System.Runtime.Serialization;

public class BookRecordSerializationBinder : SerializationBinder
{
    public override Type BindToType(string assemblyName, string typeName)
    {
        // One way to discover expected types is through testing deserialization
        // of **valid** data and logging the types used.

        ////Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')");

        if (typeName == "BookRecord")
        {
            return typeof(BookRecord);
        }
        else if (typeName == "AisleLocation")
        {
            return typeof(AisleLocation);
        }
        else
        {
            throw new ArgumentException("Unexpected type", nameof(typeName));
        }
    }
}

[DataContract]
public class BookRecord
{
    [DataMember]
    public string Title { get; set; }

    [DataMember]
    public string Author { get; set; }

    [DataMember]
    public int PageCount { get; set; }

    [DataMember]
    public AisleLocation Location { get; set; }
}

[DataContract]
public class AisleLocation
{
    [DataMember]
    public char Aisle { get; set; }

    [DataMember]
    public byte Shelf { get; set; }
}

public class ExampleClass
{
    public BookRecord DeserializeBookRecord(byte[] bytes)
    {
        NetDataContractSerializer serializer = new NetDataContractSerializer();
        serializer.Binder = new BookRecordSerializationBinder();
        using (MemoryStream ms = new MemoryStream(bytes))
        {
            return (BookRecord) serializer.Deserialize(ms);
        }
    }
}

Imports System
Imports System.IO
Imports System.Runtime.Serialization

Public Class BookRecordSerializationBinder
    Inherits SerializationBinder

    Public Overrides Function BindToType(assemblyName As String, typeName As String) As Type
        ' One way to discover expected types is through testing deserialization
        ' of **valid** data and logging the types used.

        'Console.WriteLine($"BindToType('{assemblyName}', '{typeName}')")

        If typeName = "BinaryFormatterVB.BookRecord" Then
            Return GetType(BookRecord)
        Else If typeName = "BinaryFormatterVB.AisleLocation" Then
            Return GetType(AisleLocation)
        Else
            Throw New ArgumentException("Unexpected type", NameOf(typeName))
        End If
    End Function
End Class

<DataContract()>
Public Class BookRecord
    <DataMember()>
    Public Property Title As String

    <DataMember()>
    Public Property Author As String

    <DataMember()>
    Public Property Location As AisleLocation
End Class

<DataContract()>
Public Class AisleLocation
    <DataMember()>
    Public Property Aisle As Char

    <DataMember()>
    Public Property Shelf As Byte
End Class

Public Class ExampleClass
    Public Function DeserializeBookRecord(bytes As Byte()) As BookRecord
        Dim serializer As NetDataContractSerializer = New NetDataContractSerializer()
        serializer.Binder = New BookRecordSerializationBinder()
        Using ms As MemoryStream = New MemoryStream(bytes)
            Return CType(serializer.Deserialize(ms), BookRecord)
        End Using
    End Function
End Class