Skip extensions in SetCookie parser #1049 (#1050)

src/Microsoft.Net.Http.Headers/SetCookieHeaderValue.cs

@@ -452,9 +452,15 @@ namespace Microsoft.Net.Http.Headers
                     result.HttpOnly = true;
                 }
                 // extension-av = <any CHAR except CTLs or ";">
-                else
-                {
-                    // TODO: skip it? Store it in a list?
+                else 
+                {   
+                    // TODO: skiping it for now to avoid parsing failure? Store it in a list?
+                    // = (no spaces)
+                    if (!ReadEqualsSign(input, ref offset))
+                    {
+                        return 0;
+                    }                    
+                    ReadToSemicolonOrEnd(input, ref offset);
                 }
             }
 
@@ -520,4 +526,4 @@ namespace Microsoft.Net.Http.Headers
                 ^ HttpOnly.GetHashCode();
         }
     }
-}
+}

test/Microsoft.Net.Http.Headers.Tests/SetCookieHeaderValueTest.cs

@@ -365,6 +365,18 @@ namespace Microsoft.Net.Http.Headers
             Assert.Equal(cookies, results);
         }
 
+        [Fact]
+        public void SetCookieHeaderValue_TryParse_SkipExtensionValues()
+        {
+            string cookieHeaderValue = "cookiename=value; extensionname=value;";
+
+            SetCookieHeaderValue setCookieHeaderValue;
+
+            SetCookieHeaderValue.TryParse(cookieHeaderValue, out setCookieHeaderValue);
+
+            Assert.Equal("value", setCookieHeaderValue.Value);
+        }
+
         [Theory]
         [MemberData(nameof(ListOfSetCookieHeaderDataSet))]
         public void SetCookieHeaderValue_ParseStrictList_AcceptsValidValues(IList<SetCookieHeaderValue> cookies, string[] input)