[3.1] Remove cookie name decoding

src/Http/Http/ref/Microsoft.AspNetCore.Http.Manual.cs

@@ -37,6 +37,7 @@ public RequestCookieCollection(int capacity) { }
         public bool ContainsKey(string key) { throw null; }
         public Microsoft.AspNetCore.Http.RequestCookieCollection.Enumerator GetEnumerator() { throw null; }
         public static Microsoft.AspNetCore.Http.RequestCookieCollection Parse(System.Collections.Generic.IList<string> values) { throw null; }
+        internal static RequestCookieCollection ParseInternal(System.Collections.Generic.IList<string> values, bool enableCookieNameDecoding) { throw null; }
         System.Collections.Generic.IEnumerator<System.Collections.Generic.KeyValuePair<string, string>> System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<System.String,System.String>>.GetEnumerator() { throw null; }
         System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { throw null; }
         public bool TryGetValue(string key, out string value) { throw null; }

src/Http/Http/src/Internal/RequestCookieCollection.cs

@@ -10,6 +10,9 @@ namespace Microsoft.AspNetCore.Http
 {
     internal class RequestCookieCollection : IRequestCookieCollection
     {
+        private const string EnableCookieNameDecoding = "Microsoft.AspNetCore.Http.EnableCookieNameDecoding";
+        private bool _enableCookieNameDecoding;
+
         public static readonly RequestCookieCollection Empty = new RequestCookieCollection();
         private static readonly string[] EmptyKeys = Array.Empty<string>();
         private static readonly Enumerator EmptyEnumerator = new Enumerator();
@@ -21,14 +24,15 @@ internal class RequestCookieCollection : IRequestCookieCollection
 
         public RequestCookieCollection()
         {
+            _enableCookieNameDecoding = AppContext.TryGetSwitch(EnableCookieNameDecoding, out var enabled) && enabled;
         }
 
-        public RequestCookieCollection(Dictionary<string, string> store)
+        public RequestCookieCollection(Dictionary<string, string> store) : this()
         {
             Store = store;
         }
 
-        public RequestCookieCollection(int capacity)
+        public RequestCookieCollection(int capacity) : this()
         {
             Store = new Dictionary<string, string>(capacity, StringComparer.OrdinalIgnoreCase);
         }
@@ -57,6 +61,9 @@ public string this[string key]
         }
 
         public static RequestCookieCollection Parse(IList<string> values)
+            => ParseInternal(values, AppContext.TryGetSwitch(EnableCookieNameDecoding, out var enabled) && enabled);
+
+        internal static RequestCookieCollection ParseInternal(IList<string> values, bool enableCookieNameDecoding)
         {
             if (values.Count == 0)
             {
@@ -76,7 +83,11 @@ public static RequestCookieCollection Parse(IList<string> values)
                 for (var i = 0; i < cookies.Count; i++)
                 {
                     var cookie = cookies[i];
-                    var name = Uri.UnescapeDataString(cookie.Name.Value);
+                    var name = cookie.Name.Value;
+                    if (enableCookieNameDecoding)
+                    {
+                        name = Uri.UnescapeDataString(name);
+                    }
                     var value = Uri.UnescapeDataString(cookie.Value.Value);
                     store[name] = value;
                 }
@@ -116,7 +127,8 @@ public bool ContainsKey(string key)
             {
                 return false;
             }
-            return Store.ContainsKey(key);
+            return Store.ContainsKey(key)
+                || !_enableCookieNameDecoding && Store.ContainsKey(Uri.EscapeDataString(key));
         }
 
         public bool TryGetValue(string key, out string value)
@@ -126,7 +138,9 @@ public bool TryGetValue(string key, out string value)
                 value = null;
                 return false;
             }
-            return Store.TryGetValue(key, out value);
+
+            return Store.TryGetValue(key, out value)
+                || !_enableCookieNameDecoding && Store.TryGetValue(Uri.EscapeDataString(key), out value);
         }
 
         /// <summary>

src/Http/Http/test/RequestCookiesCollectionTests.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
 using System.Linq;
 using Microsoft.Extensions.Primitives;
 using Xunit;
@@ -9,30 +10,32 @@ namespace Microsoft.AspNetCore.Http.Tests
 {
     public class RequestCookiesCollectionTests
     {
-        public static TheoryData UnEscapesKeyValues_Data
+        [Theory]
+        [InlineData("key=value", "key", "value")]
+        [InlineData("__secure-key=value", "__secure-key", "value")]
+        [InlineData("key%2C=%21value", "key,", "!value")]
+        [InlineData("ke%23y%2C=val%5Eue", "ke#y,", "val^ue")]
+        [InlineData("base64=QUI%2BREU%2FRw%3D%3D", "base64", "QUI+REU/Rw==")]
+        [InlineData("base64=QUI+REU/Rw==", "base64", "QUI+REU/Rw==")]
+        public void UnEscapesValues(string input, string expectedKey, string expectedValue)
         {
-            get
-            {
-                // key, value, expected
-                return new TheoryData<string, string, string>
-                {
-                    { "key=value", "key", "value" },
-                    { "key%2C=%21value", "key,", "!value" },
-                    { "ke%23y%2C=val%5Eue", "ke#y,", "val^ue" },
-                    { "base64=QUI%2BREU%2FRw%3D%3D", "base64", "QUI+REU/Rw==" },
-                    { "base64=QUI+REU/Rw==", "base64", "QUI+REU/Rw==" },
-                };
-            }
+            var cookies = RequestCookieCollection.Parse(new StringValues(input));
+
+            Assert.Equal(1, cookies.Count);
+            Assert.Equal(Uri.EscapeDataString(expectedKey), cookies.Keys.Single());
+            Assert.Equal(expectedValue, cookies[expectedKey]);
         }
 
         [Theory]
-        [MemberData(nameof(UnEscapesKeyValues_Data))]
-        public void UnEscapesKeyValues(
-            string input,
-            string expectedKey,
-            string expectedValue)
+        [InlineData("key=value", "key", "value")]
+        [InlineData("__secure-key=value", "__secure-key", "value")]
+        [InlineData("key%2C=%21value", "key,", "!value")]
+        [InlineData("ke%23y%2C=val%5Eue", "ke#y,", "val^ue")]
+        [InlineData("base64=QUI%2BREU%2FRw%3D%3D", "base64", "QUI+REU/Rw==")]
+        [InlineData("base64=QUI+REU/Rw==", "base64", "QUI+REU/Rw==")]
+        public void AppContextSwitchUnEscapesKeyValues(string input, string expectedKey, string expectedValue)
         {
-            var cookies = RequestCookieCollection.Parse(new StringValues(input));
+            var cookies = RequestCookieCollection.ParseInternal(new StringValues(input), enableCookieNameDecoding: true);
 
             Assert.Equal(1, cookies.Count);
             Assert.Equal(expectedKey, cookies.Keys.Single());