Unnecessary cryptographic derived types obsoletions

docs/project/list-of-diagnostics.md

@@ -70,6 +70,7 @@ The PR that reveals the implementation of the `<IncludeInternalObsoleteAttribute
 |  __`SYSLIB0018`__ | ReflectionOnly loading is not supported and throws PlatformNotSupportedException. |
 |  __`SYSLIB0019`__ | RuntimeEnvironment members SystemConfigurationFile, GetRuntimeInterfaceAsIntPtr, and GetRuntimeInterfaceAsObject are no longer supported and throw PlatformNotSupportedException. |
 |  __`SYSLIB0020`__ | JsonSerializerOptions.IgnoreNullValues is obsolete. To ignore null values when serializing, set DefaultIgnoreCondition to JsonIgnoreCondition.WhenWritingNull. |
+|  __`SYSLIB0021`__ | Derived cryptographic types are obsolete. Use the Create method on the underlying type instead. |
 
 ## Analyzer Warnings
 

src/libraries/Common/src/System/Obsoletions.cs

@@ -71,5 +71,8 @@ internal static class Obsoletions
 
         internal const string JsonSerializerOptionsIgnoreNullValuesMessage = "JsonSerializerOptions.IgnoreNullValues is obsolete. To ignore null values when serializing, set DefaultIgnoreCondition to JsonIgnoreCondition.WhenWritingNull.";
         internal const string JsonSerializerOptionsIgnoreNullValuesDiagId = "SYSLIB0020";
+
+        internal const string DerivedCryptographicTypesMessage = "Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.";
+        internal const string DerivedCryptographicTypesDiagId = "SYSLIB0021";
     }
 }

src/libraries/Directory.Build.targets

@@ -17,8 +17,12 @@
     <NoWarn Condition="'$(TargetFrameworkIdentifier)' == '.NETFramework' or '$(TargetFrameworkIdentifier)' == '.NETStandard' or ('$(TargetFrameworkIdentifier)' == '.NETCoreApp' and $([MSBuild]::VersionLessThan($(TargetFrameworkVersion), '3.0')))">$(NoWarn);nullable</NoWarn>
     <NoWarn Condition="'$(GeneratePlatformNotSupportedAssembly)' == 'true' or '$(GeneratePlatformNotSupportedAssemblyMessage)' != ''">$(NoWarn);nullable;CA1052</NoWarn>
     <!-- Ignore Obsolete errors within the generated shims that type-forward types.
-         SYSLIB0003: Code Access Security (CAS). SYSLIB0004: Constrained Execution Region (CER). SYSLIB0017: Strong name signing. -->
-    <NoWarn Condition="'$(IsPartialFacadeAssembly)' == 'true'">$(NoWarn);SYSLIB0003;SYSLIB0004;SYSLIB0015;SYSLIB0017</NoWarn>
+           SYSLIB0003: Code Access Security (CAS).
+           SYSLIB0004: Constrained Execution Region (CER).
+           SYSLIB0017: Strong name signing.
+           SYSLIB0021: Derived cryptographic types.
+    -->
+    <NoWarn Condition="'$(IsPartialFacadeAssembly)' == 'true'">$(NoWarn);SYSLIB0003;SYSLIB0004;SYSLIB0015;SYSLIB0017;SYSLIB0021</NoWarn>
     <!-- Reset these properties back to blank, since they are defaulted by Microsoft.NET.Sdk -->
     <WarningsAsErrors Condition="'$(WarningsAsErrors)' == 'NU1605'" />
     <!-- Set the documentation output file globally. -->

src/libraries/System.Runtime.Serialization.Xml/tests/System.Runtime.Serialization.Xml.Tests.csproj

@@ -1,6 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <TargetFrameworks>$(NetCoreAppCurrent)</TargetFrameworks>
+    <NoWarn>$(NoWarn);SYSLIB0021</NoWarn>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(TestSourceFolder)DataContractSerializerStressTests.cs" />

src/libraries/System.Security.Cryptography.Algorithms/ref/System.Security.Cryptography.Algorithms.cs

@@ -40,6 +40,7 @@ public void Dispose() { }
         public void Encrypt(byte[] nonce, byte[] plaintext, byte[] ciphertext, byte[] tag, byte[]? associatedData = null) { }
         public void Encrypt(System.ReadOnlySpan<byte> nonce, System.ReadOnlySpan<byte> plaintext, System.Span<byte> ciphertext, System.Span<byte> tag, System.ReadOnlySpan<byte> associatedData = default(System.ReadOnlySpan<byte>)) { }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     [System.Runtime.Versioning.UnsupportedOSPlatformAttribute("browser")]
     public sealed partial class AesManaged : System.Security.Cryptography.Aes
@@ -808,6 +809,7 @@ protected SHA1() { }
         public static int HashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination) { throw null; }
         public static bool TryHashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA1Managed : System.Security.Cryptography.SHA1
     {
@@ -830,6 +832,7 @@ protected SHA256() { }
         public static int HashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination) { throw null; }
         public static bool TryHashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA256Managed : System.Security.Cryptography.SHA256
     {
@@ -852,6 +855,7 @@ protected SHA384() { }
         public static int HashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination) { throw null; }
         public static bool TryHashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA384Managed : System.Security.Cryptography.SHA384
     {
@@ -874,6 +878,7 @@ protected SHA512() { }
         public static int HashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination) { throw null; }
         public static bool TryHashData(System.ReadOnlySpan<byte> source, System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA512Managed : System.Security.Cryptography.SHA512
     {

src/libraries/System.Security.Cryptography.Algorithms/src/System.Security.Cryptography.Algorithms.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <DefineConstants>$(DefineConstants);INTERNAL_ASYMMETRIC_IMPLEMENTATIONS</DefineConstants>
@@ -16,6 +16,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="System\Security\Cryptography\CryptoConfig.Common.cs" />
+    <Compile Include="$(CommonPath)System\Obsoletions.cs" Link="Common\System\Obsoletions.cs" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsBrowser)' != 'true'">
     <Compile Include="Internal\Cryptography\AesImplementation.cs" />

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/AesManaged.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [UnsupportedOSPlatform("browser")]
     [EditorBrowsable(EditorBrowsableState.Never)]
     public sealed class AesManaged : Aes

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/CryptoConfig.Browser.cs

@@ -33,6 +33,7 @@ public partial class CryptoConfig
 
             switch (name)
             {
+#pragma warning disable SYSLIB0021 // Obsolete: derived cryptographic types
                 // hardcode mapping for SHA* algorithm names from https://docs.microsoft.com/en-us/dotnet/api/system.security.cryptography.cryptoconfig?view=net-5.0#remarks
                 case "SHA":
                 case "SHA1":
@@ -50,6 +51,7 @@ public partial class CryptoConfig
                 case "SHA-512":
                 case "System.Security.Cryptography.SHA512":
                     return new SHA512Managed();
+#pragma warning restore SYSLIB0021
             }
 
             return null;

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/CryptoConfig.cs

@@ -120,10 +120,12 @@ private static Dictionary<string, object> DefaultNameHT
                 Type HMACSHA384Type = typeof(System.Security.Cryptography.HMACSHA384);
                 Type HMACSHA512Type = typeof(System.Security.Cryptography.HMACSHA512);
                 Type RijndaelManagedType = typeof(System.Security.Cryptography.RijndaelManaged);
+#pragma warning disable SYSLIB0021 // Obsolete: derived cryptographic types
                 Type AesManagedType = typeof(System.Security.Cryptography.AesManaged);
                 Type SHA256DefaultType = typeof(System.Security.Cryptography.SHA256Managed);
                 Type SHA384DefaultType = typeof(System.Security.Cryptography.SHA384Managed);
                 Type SHA512DefaultType = typeof(System.Security.Cryptography.SHA512Managed);
+#pragma warning restore SYSLIB0021
 
                 string SHA1CryptoServiceProviderType = "System.Security.Cryptography.SHA1CryptoServiceProvider, " + AssemblyName_Csp;
                 string MD5CryptoServiceProviderType = "System.Security.Cryptography.MD5CryptoServiceProvider," + AssemblyName_Csp;

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/SHA1Managed.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     // SHA1Managed has a copy of the same implementation as SHA1
     public sealed class SHA1Managed : SHA1

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/SHA256Managed.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     // SHA256Managed has a copy of the same implementation as SHA256
     public sealed class SHA256Managed : SHA256

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/SHA384Managed.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     // SHA384Managed has a copy of the same implementation as SHA384
     public sealed class SHA384Managed : SHA384

src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/SHA512Managed.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     // SHA512Managed has a copy of the same implementation as SHA512
     public sealed class SHA512Managed : SHA512

src/libraries/System.Security.Cryptography.Algorithms/tests/System.Security.Cryptography.Algorithms.Tests.csproj

@@ -3,6 +3,8 @@
     <TargetFrameworks>$(NetCoreAppCurrent)-windows;$(NetCoreAppCurrent)-Unix;$(NetCoreAppCurrent)-Android;$(NetCoreAppCurrent)-Browser</TargetFrameworks>
     <UseAndroidCrypto Condition="'$(TargetsAndroid)' == 'true'">true</UseAndroidCrypto>
     <UseAppleCrypto Condition="'$(TargetsOSX)' == 'true' or '$(TargetsiOS)' == 'true' or '$(TargetstvOS)' == 'true'">true</UseAppleCrypto>
+    <!-- SYSLIB0021: Derived cryptographic types are obsolete -->
+    <NoWarn>$(NoWarn);SYSLIB0021</NoWarn>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="$(CommonTestPath)System\IO\PositionValueStream.cs"

src/libraries/System.Security.Cryptography.Csp/ref/System.Security.Cryptography.Csp.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class AesCryptoServiceProvider : System.Security.Cryptography.Aes
     {
@@ -73,6 +74,7 @@ public enum CspProviderFlags
         NoPrompt = 64,
         CreateEphemeralKey = 128,
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class DESCryptoServiceProvider : System.Security.Cryptography.DES
     {
@@ -128,6 +130,7 @@ public enum KeyNumber
         Exchange = 1,
         Signature = 2,
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class MD5CryptoServiceProvider : System.Security.Cryptography.MD5
     {
@@ -164,6 +167,7 @@ protected override void Dispose(bool disposing) { }
         public override byte[] GetBytes(int cb) { throw null; }
         public override void Reset() { }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class RC2CryptoServiceProvider : System.Security.Cryptography.RC2
     {
@@ -228,6 +232,7 @@ public override void ImportParameters(System.Security.Cryptography.RSAParameters
         public override bool VerifyHash(byte[] hash, byte[] signature, System.Security.Cryptography.HashAlgorithmName hashAlgorithm, System.Security.Cryptography.RSASignaturePadding padding) { throw null; }
         public bool VerifyHash(byte[] rgbHash, string str, byte[] rgbSignature) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA1CryptoServiceProvider : System.Security.Cryptography.SHA1
     {
@@ -239,6 +244,7 @@ protected override void HashCore(System.ReadOnlySpan<byte> source) { }
         public override void Initialize() { }
         protected override bool TryHashFinal(System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA256CryptoServiceProvider : System.Security.Cryptography.SHA256
     {
@@ -250,6 +256,7 @@ protected override void HashCore(System.ReadOnlySpan<byte> source) { }
         public override void Initialize() { }
         protected override bool TryHashFinal(System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA384CryptoServiceProvider : System.Security.Cryptography.SHA384
     {
@@ -261,6 +268,7 @@ protected override void HashCore(System.ReadOnlySpan<byte> source) { }
         public override void Initialize() { }
         protected override bool TryHashFinal(System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class SHA512CryptoServiceProvider : System.Security.Cryptography.SHA512
     {
@@ -272,6 +280,7 @@ protected override void HashCore(System.ReadOnlySpan<byte> source) { }
         public override void Initialize() { }
         protected override bool TryHashFinal(System.Span<byte> destination, out int bytesWritten) { throw null; }
     }
+    [System.ObsoleteAttribute("Derived cryptographic types are obsolete. Use the Create method on the underlying type instead.", DiagnosticId = "SYSLIB0021", UrlFormat = "https://aka.ms/dotnet-warnings/{0}")]
     [System.ComponentModel.EditorBrowsableAttribute(System.ComponentModel.EditorBrowsableState.Never)]
     public sealed partial class TripleDESCryptoServiceProvider : System.Security.Cryptography.TripleDES
     {

src/libraries/System.Security.Cryptography.Csp/src/System.Security.Cryptography.Csp.csproj

@@ -131,4 +131,7 @@
     <Reference Include="System.Threading" />
     <Reference Include="System.Threading.Thread" />
   </ItemGroup>
+  <ItemGroup>
+    <Compile Include="$(CommonPath)System\Obsoletions.cs" Link="Common\System\Obsoletions.cs" />
+  </ItemGroup>
 </Project>

src/libraries/System.Security.Cryptography.Csp/src/System/Security/Cryptography/AesCryptoServiceProvider.cs

@@ -5,6 +5,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     public sealed class AesCryptoServiceProvider : Aes
     {

src/libraries/System.Security.Cryptography.Csp/src/System/Security/Cryptography/DESCryptoServiceProvider.Unix.cs

@@ -6,6 +6,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     public sealed class DESCryptoServiceProvider : DES
     {

src/libraries/System.Security.Cryptography.Csp/src/System/Security/Cryptography/DESCryptoServiceProvider.Windows.cs

@@ -7,6 +7,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     public sealed class DESCryptoServiceProvider : DES
     {

src/libraries/System.Security.Cryptography.Csp/src/System/Security/Cryptography/MD5CryptoServiceProvider.cs

@@ -5,6 +5,7 @@
 
 namespace System.Security.Cryptography
 {
+    [Obsolete(Obsoletions.DerivedCryptographicTypesMessage, DiagnosticId = Obsoletions.DerivedCryptographicTypesDiagId, UrlFormat = Obsoletions.SharedUrlFormat)]
     [EditorBrowsable(EditorBrowsableState.Never)]
     public sealed class MD5CryptoServiceProvider : MD5
     {

src/libraries/System.Security.Cryptography.Csp/src/System/Security/Cryptography/PasswordDeriveBytes.cs

@@ -41,6 +41,7 @@ public PasswordDeriveBytes(byte[] password, byte[]? salt, string hashName, int i
             this(password, salt, hashName, iterations, new CspParameters()) { }
 #pragma warning restore CA1416
 
+#pragma warning disable SYSLIB0021 // Obsolete: derived cryptographic types
         [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2026:RequiresUnreferencedCode", Justification = "The correct hash algorithm is being preserved by the DynamicDependency.")]
         [DynamicDependency(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor, typeof(SHA1CryptoServiceProvider))]
         public PasswordDeriveBytes(string strPassword, byte[]? rgbSalt, CspParameters? cspParams) :
@@ -50,6 +51,7 @@ public PasswordDeriveBytes(string strPassword, byte[]? rgbSalt, CspParameters? c
         [DynamicDependency(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor, typeof(SHA1CryptoServiceProvider))]
         public PasswordDeriveBytes(byte[] password, byte[]? salt, CspParameters? cspParams) :
             this(password, salt, "SHA1", 100, cspParams) { }
+#pragma warning restore SYSLIB0021
 
         [RequiresUnreferencedCode(HashAlgorithmUnreferencedCodeMessage)]
         public PasswordDeriveBytes(string strPassword, byte[]? rgbSalt, string strHashName, int iterations, CspParameters? cspParams) :