Use user-provided values as Utf8

src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonWebToken.PayloadClaimSet.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Text;
 using System.Text.Json;
 using Microsoft.IdentityModel.Logging;
 using Microsoft.IdentityModel.Tokens;
@@ -78,8 +79,10 @@ internal JsonClaimSet CreatePayloadClaimSet(ReadOnlySpan<byte> byteSpan)
                     }
                     else if (reader.ValueTextEquals(JwtPayloadUtf8Bytes.Iss))
                     {
-                        _iss = JsonSerializerPrimitives.ReadString(ref reader, JwtRegisteredClaimNames.Iss, ClassName, true);
-                        claims[JwtRegisteredClaimNames.Iss] = _iss;
+
+                        IssuerUtf8 = JsonSerializerPrimitives.ReadStringUtf8(ref reader, JwtRegisteredClaimNames.Jti, ClassName, true).ToArray();
+                        claims[JwtRegisteredClaimNames.Iss] = Encoding.UTF8.GetString(IssuerUtf8.ToArray());
+                        reader.Read();
                     }
                     else if (reader.ValueTextEquals(JwtPayloadUtf8Bytes.Jti))
                     {

src/Microsoft.IdentityModel.JsonWebTokens/JsonWebToken.cs

@@ -53,7 +53,6 @@ public partial class JsonWebToken : SecurityToken
         internal long? _iat;
         internal DateTime? _iatDateTime;
         internal string _id;
-        internal string _iss;
         internal string _jti;
         internal string _sub;
         internal long? _nbf;
@@ -1031,14 +1030,9 @@ public DateTime IssuedAt
         /// If the 'iss' claim is not found, an empty string is returned.
         /// </para>
         /// </remarks>
-        public override string Issuer
-        {
-            get
-            {
-                _iss ??= Payload.GetStringValue(JwtRegisteredClaimNames.Iss);
-                return _iss;
-            }
-        }
+        public override string Issuer => Encoding.UTF8.GetString(IssuerUtf8.ToArray());
+
+        internal ReadOnlyMemory<byte> IssuerUtf8 { get; set; }
 
         /// <summary>
         /// Gets the 'value' of the 'jti' claim from the payload.

src/Microsoft.IdentityModel.JsonWebTokens/JsonWebTokenHandler.cs

@@ -845,7 +845,7 @@ private async ValueTask<TokenValidationResult> ValidateTokenPayloadAsync(JsonWeb
 
             Validators.ValidateLifetime(notBefore, expires, jsonWebToken, validationParameters);
             Validators.ValidateAudience(jsonWebToken.Audiences, jsonWebToken, validationParameters);
-            string issuer = await Validators.ValidateIssuerAsync(jsonWebToken.Issuer, jsonWebToken, validationParameters, configuration).ConfigureAwait(false);
+            string issuer = await Validators.ValidateIssuerAsync(jsonWebToken.IssuerUtf8, jsonWebToken, validationParameters, configuration).ConfigureAwait(false);
 
             Validators.ValidateTokenReplay(expires, jsonWebToken.EncodedToken, validationParameters);
             if (validationParameters.ValidateActor && !string.IsNullOrWhiteSpace(jsonWebToken.Actor))

src/Microsoft.IdentityModel.Tokens/BaseConfiguration.cs

@@ -1,8 +1,10 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
+using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
+using System.Text;
 using System.Text.Json.Serialization;
 
 namespace Microsoft.IdentityModel.Tokens
@@ -12,10 +14,22 @@ namespace Microsoft.IdentityModel.Tokens
     /// </summary>
     public abstract class BaseConfiguration
     {
+        private string _issuer;
+
         /// <summary>
         /// Gets the issuer specified via the metadata endpoint.
         /// </summary>
-        public virtual string Issuer { get; set; }
+        public virtual string Issuer
+        {
+            get => _issuer;
+            set
+            {
+                _issuer = value;
+                IssuerUtf8 = value != null ? Encoding.UTF8.GetBytes(value) : null;
+            }
+        }
+
+        internal ReadOnlyMemory<byte> IssuerUtf8 { get; private set; }
 
         /// <summary>
         /// Gets the <see cref="ICollection{SecurityKey}"/> that the IdentityProvider indicates are to be used in order to sign tokens.

src/Microsoft.IdentityModel.Tokens/Json/JsonSerializerPrimitives.cs

@@ -644,6 +644,19 @@ internal static string ReadString(ref Utf8JsonReader reader, string propertyName
             return retval;
         }
 
+        internal static ReadOnlySpan<byte> ReadStringUtf8(ref Utf8JsonReader reader, string propertyName, string className, bool read = false)
+        {
+            // returning null keeps the same logic as JsonSerialization.ReadObject
+            if (IsReaderPositionedOnNull(ref reader, read, true))
+                return null;
+
+            if (!IsReaderAtTokenType(ref reader, JsonTokenType.String, false))
+                throw LogHelper.LogExceptionMessage(
+                    CreateJsonReaderExceptionInvalidType(ref reader, "JsonTokenType.StartArray", className, propertyName));
+
+            return reader.ValueSpan;
+        }
+
         internal static string ReadStringAsBool(ref Utf8JsonReader reader, string propertyName, string className, bool read = false)
         {
             // The parameter 'read' can be used by callers reader position the reader to the next token.

src/Microsoft.IdentityModel.Tokens/TokenValidationParameters.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Security.Claims;
+using System.Text;
 using System.Threading.Tasks;
 using Microsoft.IdentityModel.Abstractions;
 using Microsoft.IdentityModel.Logging;
@@ -112,7 +113,7 @@ namespace Microsoft.IdentityModel.Tokens
     /// <remarks>The delegate should return a non null string that represents the 'issuer'. If null a default value will be used.
     /// <see cref="IssuerValidatorAsync"/> if set, will be called before <see cref="IssuerSigningKeyValidatorUsingConfiguration"/> or <see cref="IssuerSigningKeyValidator"/>
     /// </remarks>
-    internal delegate ValueTask<string> IssuerValidatorAsync(string issuer, SecurityToken securityToken, TokenValidationParameters validationParameters);
+    internal delegate ValueTask<string> IssuerValidatorAsync(ReadOnlyMemory<byte> issuer, SecurityToken securityToken, TokenValidationParameters validationParameters);
 
     /// <summary>
     /// Definition for LifetimeValidator.
@@ -893,11 +894,23 @@ public string RoleClaimType
         /// </summary>
         public IEnumerable<string> ValidAudiences { get; set; }
 
+        private string _validIssuer;
+
         /// <summary>
         /// Gets or sets a <see cref="string"/> that represents a valid issuer that will be used to check against the token's issuer.
         /// The default is <c>null</c>.
         /// </summary>
-        public string ValidIssuer { get; set; }
+        public string ValidIssuer
+        {
+            get => _validIssuer;
+            set
+            {
+                _validIssuer = value;
+                ValidIssuerUtf8 = value != null ? Encoding.UTF8.GetBytes(value) : null;
+            }
+        }
+
+        internal ReadOnlyMemory<byte> ValidIssuerUtf8 { get; private set; }
 
         /// <summary>
         /// Gets or sets the <see cref="IEnumerable{String}"/> that contains valid issuers that will be used to check against the token's issuer.

src/Microsoft.IdentityModel.Tokens/Validators.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Security.Cryptography.X509Certificates;
+using System.Text;
 using System.Threading.Tasks;
 using Microsoft.IdentityModel.Abstractions;
 using Microsoft.IdentityModel.Logging;
@@ -219,7 +220,7 @@ public static string ValidateIssuer(string issuer, SecurityToken securityToken,
         /// <remarks>An EXACT match is required.</remarks>
         internal static string ValidateIssuer(string issuer, SecurityToken securityToken, TokenValidationParameters validationParameters, BaseConfiguration configuration)
         {
-            ValueTask<string> vt = ValidateIssuerAsync(issuer, securityToken, validationParameters, configuration);
+            ValueTask<string> vt = ValidateIssuerAsync(Encoding.UTF8.GetBytes(issuer), securityToken, validationParameters, configuration);
             return vt.IsCompletedSuccessfully ?
                 vt.Result :
                 vt.AsTask().GetAwaiter().GetResult();
@@ -228,7 +229,7 @@ internal static string ValidateIssuer(string issuer, SecurityToken securityToken
         /// <summary>
         /// Determines if an issuer found in a <see cref="SecurityToken"/> is valid.
         /// </summary>
-        /// <param name="issuer">The issuer to validate</param>
+        /// <param name="issuerUtf8">The issuer to validate</param>
         /// <param name="securityToken">The <see cref="SecurityToken"/> that is being validated.</param>
         /// <param name="validationParameters"><see cref="TokenValidationParameters"/> required for validation.</param>
         /// <param name="configuration">The <see cref="BaseConfiguration"/> required for issuer and signing key validation.</param>
@@ -240,7 +241,7 @@ internal static string ValidateIssuer(string issuer, SecurityToken securityToken
         /// <exception cref="SecurityTokenInvalidIssuerException">If 'issuer' failed to matched either <see cref="TokenValidationParameters.ValidIssuer"/> or one of <see cref="TokenValidationParameters.ValidIssuers"/> or <see cref="BaseConfiguration.Issuer"/>.</exception>
         /// <remarks>An EXACT match is required.</remarks>
         internal static async ValueTask<string> ValidateIssuerAsync(
-            string issuer,
+            ReadOnlyMemory<byte> issuerUtf8,
             SecurityToken securityToken,
             TokenValidationParameters validationParameters,
             BaseConfiguration configuration)
@@ -249,7 +250,9 @@ internal static async ValueTask<string> ValidateIssuerAsync(
                 throw LogHelper.LogArgumentNullException(nameof(validationParameters));
 
             if (validationParameters.IssuerValidatorAsync != null)
-                return await validationParameters.IssuerValidatorAsync(issuer, securityToken, validationParameters).ConfigureAwait(false);
+                return await validationParameters.IssuerValidatorAsync(issuerUtf8, securityToken, validationParameters).ConfigureAwait(false);
+
+            string issuer = issuerUtf8.ToString();
 
             if (validationParameters.IssuerValidatorUsingConfiguration != null)
                 return validationParameters.IssuerValidatorUsingConfiguration(issuer, securityToken, validationParameters, configuration);
@@ -276,7 +279,7 @@ internal static async ValueTask<string> ValidateIssuerAsync(
 
             if (configuration != null)
             {
-                if (string.Equals(configuration.Issuer, issuer))
+                if (string.Equals(configuration.IssuerUtf8, issuerUtf8))
                 {
                     if (LogHelper.IsEnabled(EventLogLevel.Informational))
                         LogHelper.LogInformation(LogMessages.IDX10236, LogHelper.MarkAsNonPII(issuer));
@@ -285,7 +288,7 @@ internal static async ValueTask<string> ValidateIssuerAsync(
                 }
             }
 
-            if (string.Equals(validationParameters.ValidIssuer, issuer))
+            if (validationParameters.ValidIssuerUtf8.Equals(issuerUtf8))
             {
                 if (LogHelper.IsEnabled(EventLogLevel.Informational))
                     LogHelper.LogInformation(LogMessages.IDX10236, LogHelper.MarkAsNonPII(issuer));