Adding withCertificate overload to use cert serial number

src/client/Microsoft.Identity.Client/ApiConfig/AcquireTokenForClientParameterBuilder.cs

@@ -41,7 +41,17 @@ internal static AcquireTokenForClientParameterBuilder Create(
             IConfidentialClientApplicationExecutor confidentialClientApplicationExecutor,
             IEnumerable<string> scopes)
         {
-            return new AcquireTokenForClientParameterBuilder(confidentialClientApplicationExecutor).WithScopes(scopes);
+            var builder = new AcquireTokenForClientParameterBuilder(confidentialClientApplicationExecutor).WithScopes(scopes);
+
+            if (!string.IsNullOrEmpty(confidentialClientApplicationExecutor.ServiceBundle.Config.CertificateIdToAssociateWithToken))
+            {
+                builder.WithAdditionalCacheKeyComponents(new SortedList<string, string>
+                {
+                    { Constants.CertSerialNumber, confidentialClientApplicationExecutor.ServiceBundle.Config.CertificateIdToAssociateWithToken }
+                });
+            }
+
+            return builder;
         }
 
         /// <summary>

src/client/Microsoft.Identity.Client/AppConfig/ApplicationConfiguration.cs

@@ -121,6 +121,7 @@ public string ClientVersion
         public bool IsManagedIdentity { get; }
         public bool IsConfidentialClient { get; }
         public bool IsPublicClient => !IsConfidentialClient && !IsManagedIdentity;
+        public string CertificateIdToAssociateWithToken { get; set; }
 
         public Func<AppTokenProviderParameters, Task<AppTokenProviderResult>> AppTokenProvider;
 

src/client/Microsoft.Identity.Client/Extensibility/RP/ConfidentialClientApplicationBuilderForResourceProviders.cs

@@ -0,0 +1,47 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using System.Security.Cryptography.X509Certificates;
+
+namespace Microsoft.Identity.Client.RP
+{
+    /// <summary>
+    /// Resource Provider extensibility methods for <see cref="ConfidentialClientApplicationBuilder"/>
+    /// </summary>
+#if !SUPPORTS_CONFIDENTIAL_CLIENT
+    [System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Never)]  // hide confidential client on mobile
+#endif
+    public static class ConfidentialClientApplicationBuilderForResourceProviders
+    {
+        /// <summary>
+        /// Sets the certificate associated with the application.
+        /// Applicable to first-party applications only, this method also allows to specify 
+        /// if the <see href="https://datatracker.ietf.org/doc/html/rfc7517#section-4.7">x5c claim</see> should be sent to Azure AD.
+        /// Sending the x5c enables application developers to achieve easy certificate roll-over in Azure AD:
+        /// this method will send the certificate chain to Azure AD along with the token request,
+        /// so that Azure AD can use it to validate the subject name based on a trusted issuer policy.
+        /// This saves the application admin from the need to explicitly manage the certificate rollover
+        /// (either via portal or PowerShell/CLI operation). For details see https://aka.ms/msal-net-sni
+        /// This API allow you to associate the tokens acquired from Azure AD with the certificate serial number. 
+        /// This can be used to partition the cache by certificate. Tokens acquired with one certificate will not be accessible to another certificate with a different serial number.
+        /// </summary>
+        /// <param name="builder"></param>
+        /// <param name="certificate">The X509 certificate used as credentials to prove the identity of the application to Azure AD.</param>
+        /// <param name="sendX5C">To send X5C with every request or not. The default is <c>false</c></param>
+        /// <param name="associateTokensWithCertificateSerialNumber">Determines if the application tokens acquired from Azure AD are associated with the certificate serial number</param>
+        /// <remarks>You should use certificates with a private key size of at least 2048 bytes. Future versions of this library might reject certificates with smaller keys. </remarks>
+        public static ConfidentialClientApplicationBuilder WithCertificate(
+            this ConfidentialClientApplicationBuilder builder,
+            X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber)
+        {
+            builder.WithCertificate(certificate, sendX5C);
+
+            if (associateTokensWithCertificateSerialNumber)
+            {
+                builder.Config.CertificateIdToAssociateWithToken = certificate.SerialNumber;
+            }
+
+            return builder;
+        }
+    }
+}

src/client/Microsoft.Identity.Client/Internal/Constants.cs

@@ -48,6 +48,7 @@ internal static class Constants
         public const string ManagedIdentityDefaultClientId = "system_assigned_managed_identity";
         public const string ManagedIdentityDefaultTenant = "managed_identity";
         public const string CiamAuthorityHostSuffix = ".ciamlogin.com";
+        public const string CertSerialNumber = "cert_sn";
 
         public const int CallerSdkIdMaxLength = 10;
         public const int CallerSdkVersionMaxLength = 20;

src/client/Microsoft.Identity.Client/Microsoft.Identity.Client.csproj

@@ -80,6 +80,7 @@
     <Compile Include="$(PathToMsalSources)\**\*.cs" Exclude="$(PathToMsalSources)\obj\**\*.*" />
     <Compile Remove="$(PathToMsalSources)\Platforms\**\*.*;$(PathToMsalSources)\Resources\*.cs" />
     <Compile Remove="$(PathToMsalSources)\PlatformsCommon\PlatformNotSupported\ApiConfig\SystemWebViewOptions.cs" />
+    <None Remove="Extensibility\RP\ConfidentialClientApplicationBuilderForResourceProviders.cs" />
     <EmbeddedResource Include="$(PathToMsalSources)\Properties\Microsoft.Identity.Client.rd.xml" />
     <None Include="$(PathToMsalSources)\..\..\..\README.md" Pack="true" PackagePath="\" />
     <None Include="Platforms\net\JsonObjectAttribute.cs" />
@@ -163,4 +164,8 @@
     <AdditionalFiles Include="PublicAPI/$(TargetFramework)/PublicAPI.Shipped.txt" />
     <AdditionalFiles Include="PublicAPI/$(TargetFramework)/PublicAPI.Unshipped.txt" />
   </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="Extensibility\RP\ConfidentialClientApplicationBuilderForResourceProviders.cs" />
+  </ItemGroup>
 </Project>

src/client/Microsoft.Identity.Client/PublicApi/net462/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
-Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

src/client/Microsoft.Identity.Client/PublicApi/net472/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
-Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

src/client/Microsoft.Identity.Client/PublicApi/net8.0-android/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

src/client/Microsoft.Identity.Client/PublicApi/net8.0-ios/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

src/client/Microsoft.Identity.Client/PublicApi/net8.0/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

src/client/Microsoft.Identity.Client/PublicApi/netstandard2.0/PublicAPI.Unshipped.txt

@@ -1,3 +1,5 @@
 Microsoft.Identity.Client.BrokerOptions.OperatingSystems.Linux = 2 -> Microsoft.Identity.Client.BrokerOptions.OperatingSystems
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.get -> System.Collections.Generic.IEnumerable<string>
 Microsoft.Identity.Client.AssertionRequestOptions.ClientCapabilities.set -> void
+Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders
+static Microsoft.Identity.Client.RP.ConfidentialClientApplicationBuilderForResourceProviders.WithCertificate(this Microsoft.Identity.Client.ConfidentialClientApplicationBuilder builder, System.Security.Cryptography.X509Certificates.X509Certificate2 certificate, bool sendX5C, bool associateTokensWithCertificateSerialNumber) -> Microsoft.Identity.Client.ConfidentialClientApplicationBuilder

tests/Microsoft.Identity.Test.Unit/Helpers/CertHelper.cs

@@ -12,16 +12,21 @@ public static class CertHelper
     {
         private static Dictionary<KnownTestCertType, X509Certificate2> s_x509Certificates = new Dictionary<KnownTestCertType, X509Certificate2>();
 
-        public static X509Certificate2 GetOrCreateTestCert(KnownTestCertType knownTestCertType = KnownTestCertType.RSA)
+        public static X509Certificate2 GetOrCreateTestCert(KnownTestCertType knownTestCertType = KnownTestCertType.RSA, bool regenerateCert = false)
         {
             // create the cert if it doesn't exist. use a lock to prevent multiple threads from creating the cert
             s_x509Certificates.TryGetValue(knownTestCertType, out X509Certificate2 x509Certificate2);
 
-            if (x509Certificate2 == null)
+            if (x509Certificate2 == null || regenerateCert)
             {
                 lock (typeof(CertHelper))
                 {
-                    if (x509Certificate2 == null)
+                    if (x509Certificate2 != null)
+                    {
+                        x509Certificate2 = CreateTestCert(knownTestCertType);
+                        s_x509Certificates[knownTestCertType] = x509Certificate2;
+                    }
+                    else
                     {
                         x509Certificate2 = CreateTestCert(knownTestCertType);
                         s_x509Certificates.Add(knownTestCertType, x509Certificate2);