In JsonWebToken use the values as bytes instead of converting to string

src/Microsoft.IdentityModel.JsonWebTokens/Json/JsonClaimSet.cs

@@ -7,6 +7,7 @@
 using System.Collections.ObjectModel;
 using System.Globalization;
 using System.Security.Claims;
+using System.Text;
 using System.Text.Json;
 using Microsoft.IdentityModel.Logging;
 using Microsoft.IdentityModel.Tokens;
@@ -24,14 +25,44 @@ internal class JsonClaimSet
 
         internal object _claimsLock = new();
         internal readonly Dictionary<string, object> _jsonClaims;
+
+#if NET8_0_OR_GREATER
+        internal readonly Dictionary<string, (int startIndex, int length)?> _jsonClaimsBytes;
+        internal readonly Memory<byte> _tokenAsMemory;
+#endif
+
         private List<Claim> _claims;
 
-        internal JsonClaimSet() { _jsonClaims = new Dictionary<string, object>(); }
+        internal JsonClaimSet()
+        {
+            _jsonClaims = [];
+
+#if NET8_0_OR_GREATER
+            _jsonClaimsBytes = [];
+            _tokenAsMemory = Memory<byte>.Empty;
+#endif
+        }
 
         internal JsonClaimSet(Dictionary<string, object> jsonClaims)
         {
             _jsonClaims = jsonClaims;
+
+#if NET8_0_OR_GREATER
+            _jsonClaimsBytes = [];
+#endif
+        }
+
+#if NET8_0_OR_GREATER
+        internal JsonClaimSet(
+            Dictionary<string, object> jsonClaims,
+            Dictionary<string, (int startIndex, int length)?> jsonClaimsBytes,
+            Memory<byte> tokenAsMemory)
+        {
+            _jsonClaims = jsonClaims;
+            _jsonClaimsBytes = jsonClaimsBytes;
+            _tokenAsMemory = tokenAsMemory;
         }
+#endif
 
         internal List<Claim> Claims(string issuer)
         {
@@ -48,6 +79,14 @@ internal List<Claim> CreateClaims(string issuer)
             foreach (KeyValuePair<string, object> kvp in _jsonClaims)
                 CreateClaimFromObject(claims, kvp.Key, kvp.Value, issuer);
 
+#if NET8_0_OR_GREATER
+            // _jsonClaimsBytes is only for string values for known claims, which would not be in _jsonClaims.
+            foreach (KeyValuePair<string, (int StartIndex, int Length)?> kvp in _jsonClaimsBytes)
+            {
+                string value = Encoding.UTF8.GetString(_tokenAsMemory.Slice(kvp.Value.Value.StartIndex, kvp.Value.Value.Length).Span);
+                claims.Add(new Claim(kvp.Key, value, ClaimValueTypes.String, issuer, issuer));
+            }
+#endif
             return claims;
         }
 
@@ -71,7 +110,7 @@ internal static void CreateClaimFromObject(List<Claim> claims, string claimType,
             else if (value is double d)
                 claims.Add(new Claim(claimType, d.ToString(CultureInfo.InvariantCulture), ClaimValueTypes.Double, issuer, issuer));
             else if (value is DateTime dt)
-                claims.Add(new Claim(claimType, dt.ToString("o",CultureInfo.InvariantCulture), ClaimValueTypes.DateTime, issuer, issuer));
+                claims.Add(new Claim(claimType, dt.ToString("o", CultureInfo.InvariantCulture), ClaimValueTypes.DateTime, issuer, issuer));
             else if (value is float f)
                 claims.Add(new Claim(claimType, f.ToString(CultureInfo.InvariantCulture), ClaimValueTypes.Double, issuer, issuer));
             else if (value is decimal m)
@@ -147,7 +186,11 @@ internal Claim GetClaim(string key, string issuer)
             if (key == null)
                 throw LogHelper.LogArgumentNullException(nameof(key));
 
+#if NET8_0_OR_GREATER
+            if (_jsonClaims.TryGetValue(key, out object _) || _jsonClaimsBytes.TryGetValue(key, out _))
+#else
             if (_jsonClaims.TryGetValue(key, out object _))
+#endif
             {
                 foreach (var claim in Claims(issuer))
                     if (claim.Type == key)
@@ -159,17 +202,42 @@ internal Claim GetClaim(string key, string issuer)
 
         internal string GetStringValue(string key)
         {
+#if NET8_0_OR_GREATER
+            if (_jsonClaimsBytes.TryGetValue(key, out (int StartIndex, int Length)? location))
+            {
+                if (!location.HasValue)
+                    return null;
+
+                return Encoding.UTF8.GetString(_tokenAsMemory.Slice(location.Value.StartIndex, location.Value.Length).Span);
+            }
+#else
             if (_jsonClaims.TryGetValue(key, out object obj))
             {
                 if (obj == null)
                     return null;
 
                 return obj.ToString();
             }
-
+#endif
             return string.Empty;
         }
 
+#if NET8_0_OR_GREATER
+        // Similar to GetStringValue but returns the bytes directly.
+        internal ReadOnlySpan<byte> GetStringBytesValue(string key)
+        {
+            if (_jsonClaimsBytes.TryGetValue(key, out (int StartIndex, int Length)? location))
+            {
+                if (!location.HasValue)
+                    return null;
+
+                return _tokenAsMemory.Slice(location.Value.StartIndex, location.Value.Length).Span;
+            }
+
+            return new Span<byte>();
+        }
+#endif
+
         internal DateTime GetDateTime(string key)
         {
             long l = GetValue<long>(key, false, out bool found);
@@ -317,7 +385,7 @@ internal T GetValue<T>(string key, bool throwEx, out bool found)
             else if (typeof(T) == typeof(Collection<object>))
                 return (T)(object)new Collection<object> { obj };
 
-            else if(typeof(T).IsEnum)
+            else if (typeof(T).IsEnum)
             {
                 return (T)Enum.Parse(typeof(T), obj.ToString(), ignoreCase: true);
             }
@@ -339,15 +407,15 @@ internal T GetValue<T>(string key, bool throwEx, out bool found)
                 if (objType == typeof(long))
                     return (T)(object)new long[] { (long)obj };
 
-                if(objType == typeof(int))
+                if (objType == typeof(int))
                     return (T)(object)new long[] { (int)obj };
 
                 if (long.TryParse(obj.ToString(), out long value))
                     return (T)(object)new long[] { value };
             }
             else if (typeof(T) == typeof(double))
             {
-                if(double.TryParse(obj.ToString(), out double value))
+                if (double.TryParse(obj.ToString(), out double value))
                     return (T)(object)value;
             }
             else if (typeof(T) == typeof(uint))
@@ -422,13 +490,28 @@ internal bool TryGetClaim(string key, string issuer, out Claim claim)
         /// <returns></returns>
         internal bool TryGetValue<T>(string key, out T value)
         {
+#if NET8_0_OR_GREATER
+            if (typeof(T) == typeof(string))
+            {
+                var span = GetStringBytesValue(key);
+                if (!span.IsEmpty)
+                {
+                    value = (T)(object)Encoding.UTF8.GetString(span);
+                    return true;
+                }
+            }
+#endif
             value = GetValue<T>(key, false, out bool found);
             return found;
         }
 
         internal bool HasClaim(string claimName)
         {
-            return _jsonClaims.TryGetValue(claimName, out _);
+#if NET8_0_OR_GREATER
+            return _jsonClaims.ContainsKey(claimName) || _jsonClaimsBytes.ContainsKey(claimName);
+#else
+            return _jsonClaims.ContainsKey(claimName);
+#endif
         }
     }
 }

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

@@ -13,17 +13,17 @@
     {
         internal JsonClaimSet CreateHeaderClaimSet(byte[] bytes)
         {
-            return CreateHeaderClaimSet(bytes.AsSpan());
+            return CreateHeaderClaimSet(bytes.AsMemory());
         }
 
         internal JsonClaimSet CreateHeaderClaimSet(byte[] bytes, int length)
         {
-            return CreateHeaderClaimSet(bytes.AsSpan(0, length));
+            return CreateHeaderClaimSet(bytes.AsMemory(0, length));
         }
 
-        internal JsonClaimSet CreateHeaderClaimSet(ReadOnlySpan<byte> byteSpan)
-        { 
-            Utf8JsonReader reader = new(byteSpan);
+        internal JsonClaimSet CreateHeaderClaimSet(Memory<byte> tokenHeaderAsMemory)
+        {
+            Utf8JsonReader reader = new(tokenHeaderAsMemory.Span);
             if (!JsonSerializerPrimitives.IsReaderAtTokenType(ref reader, JsonTokenType.StartObject, true))
                 throw LogHelper.LogExceptionMessage(
                     new JsonException(
@@ -36,46 +36,19 @@
                         LogHelper.MarkAsNonPII(reader.CurrentDepth),
                         LogHelper.MarkAsNonPII(reader.BytesConsumed))));
 
-            Dictionary<string, object> claims = new();
+            Dictionary<string, object> claims = [];
+#if NET8_0_OR_GREATER
+            Dictionary<string, (int startIndex, int length)?> claimsBytes = [];
+#endif
             while (true)
             {
                 if (reader.TokenType == JsonTokenType.PropertyName)
                 {
-                    if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
-                    {
-                        _alg = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Alg, ClassName, true);
-                        claims[JwtHeaderParameterNames.Alg] = _alg;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
-                    {
-                        _cty = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Cty, ClassName, true);
-                        claims[JwtHeaderParameterNames.Cty] = _cty;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
-                    {
-                        _kid = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Kid, ClassName, true);
-                        claims[JwtHeaderParameterNames.Kid] = _kid;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
-                    {
-                        _typ = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Typ, ClassName, true);
-                        claims[JwtHeaderParameterNames.Typ] = _typ;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
-                    {
-                        _x5t = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.X5t, ClassName, true);
-                        claims[JwtHeaderParameterNames.X5t] = _x5t;
-                    }
-                    else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
-                    {
-                        _zip = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Zip, ClassName, true);
-                        claims[JwtHeaderParameterNames.Zip] = _zip;
-                    }
-                    else
-                    {
-                        string propertyName = reader.GetString();
-                        claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
-                    }
+#if NET8_0_OR_GREATER
+                    ReadHeaderValue(ref reader, claims, claimsBytes, tokenHeaderAsMemory);
+#else
+                    ReadHeaderValue(ref reader, claims);
+#endif
                 }
                 // We read a JsonTokenType.StartObject above, exiting and positioning reader at next token.
                 else if (JsonSerializerPrimitives.IsReaderAtTokenType(ref reader, JsonTokenType.EndObject, false))
@@ -84,7 +57,94 @@
                     break;
             };
 
+#if NET8_0_OR_GREATER
+            return new JsonClaimSet(claims, claimsBytes, tokenHeaderAsMemory);
+#else
             return new JsonClaimSet(claims);
+#endif
+        }
+
+        private protected virtual void ReadHeaderValue(ref Utf8JsonReader reader, IDictionary<string, object> claims)
+        {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+
+            if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
+            {
+                _alg = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Alg, ClassName, true);
+                claims[JwtHeaderParameterNames.Alg] = _alg;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
+            {
+                _cty = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Cty, ClassName, true);
+                claims[JwtHeaderParameterNames.Cty] = _cty;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
+            {
+                _kid = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Kid, ClassName, true);
+                claims[JwtHeaderParameterNames.Kid] = _kid;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
+            {
+                _typ = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Typ, ClassName, true);
+                claims[JwtHeaderParameterNames.Typ] = _typ;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
+            {
+                _x5t = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.X5t, ClassName, true);
+                claims[JwtHeaderParameterNames.X5t] = _x5t;
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
+            {
+                _zip = JsonSerializerPrimitives.ReadString(ref reader, JwtHeaderParameterNames.Zip, ClassName, true);
+                claims[JwtHeaderParameterNames.Zip] = _zip;
+            }
+            else
+            {
+                string propertyName = reader.GetString();
+                claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
+            }
+        }
+
+#if NET8_0_OR_GREATER
+        private protected virtual void ReadHeaderValue(
+            ref Utf8JsonReader reader,
+            Dictionary<string, object> claims,
+            Dictionary<string, (int startIndex, int length)?> claimsBytes,
+            Memory<byte> tokenAsMemory)
+        {
+            _ = claims ?? throw LogHelper.LogArgumentNullException(nameof(claims));
+            _ = claimsBytes ?? throw LogHelper.LogArgumentNullException(nameof(claimsBytes));
+
+            if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Alg))
+            {
+                claimsBytes[JwtHeaderParameterNames.Alg] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtRegisteredClaimNames.Alg, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Cty))
+            {
+                claimsBytes[JwtHeaderParameterNames.Cty] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Cty, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Kid))
+            {
+                claimsBytes[JwtHeaderParameterNames.Kid] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Kid, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Typ))
+            {
+                claimsBytes[JwtHeaderParameterNames.Typ] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Typ, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.X5t))
+            {
+                claimsBytes[JwtHeaderParameterNames.X5t] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.X5t, ClassName, true);
+            }
+            else if (reader.ValueTextEquals(JwtHeaderUtf8Bytes.Zip))
+            {
+                claimsBytes[JwtHeaderParameterNames.Zip] = JsonSerializerPrimitives.ReadStringBytesLocation(ref reader, tokenAsMemory, JwtHeaderParameterNames.Zip, ClassName, true);
+            }
+            else
+            {
+                string propertyName = reader.GetString();
+                claims[propertyName] = JsonSerializerPrimitives.ReadPropertyValueAsObject(ref reader, propertyName, JsonClaimSet.ClassName, true);
+            }
         }
+#endif
     }
 }