fix(http.sys): correctly parse port values in range [32768:65535]

src/Servers/HttpSys/HttpSysServer.slnf

@@ -55,4 +55,4 @@
       "src\\WebEncoders\\src\\Microsoft.Extensions.WebEncoders.csproj"
     ]
   }
-}
+}

src/Servers/HttpSys/test/Tests/NativeInterop/SocketAddressTests.cs

@@ -0,0 +1,62 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Net;
+using Microsoft.AspNetCore.HttpSys.Internal;
+using Windows.Win32.Networking.WinSock;
+using Xunit;
+using static Microsoft.AspNetCore.HttpSys.Internal.SocketAddress;
+using SocketAddress = Microsoft.AspNetCore.HttpSys.Internal.SocketAddress;
+
+namespace Microsoft.AspNetCore.Server.HttpSys.Tests.NativeInterop;
+
+public class SocketAddressTests
+{
+    [Theory]
+    [InlineData(80)]
+    [InlineData(443)]
+    [InlineData(8080)]
+    [InlineData(32767)]  // max signed short
+    [InlineData(32768)]  // min value that causes negative when cast to short
+    [InlineData(42000)]
+    [InlineData(65535)]  // Max port number
+    public void IPv6_GetPort_ReturnsCorrectPort_ForAllValidPorts(ushort expectedPort)
+    {
+        var nativeIpV6Address = new SOCKADDR_IN6
+        {
+            sin6_family = ADDRESS_FAMILY.AF_INET6,
+            sin6_port = (ushort)IPAddress.HostToNetworkOrder((short)expectedPort)
+        };
+
+        var socketAddress = new SocketAddressIPv6(nativeIpV6Address);
+        var actualPort = socketAddress.GetPort();
+
+        Assert.Equal(expectedPort, actualPort);
+        Assert.True(actualPort >= 0, "Port should never be negative");
+        Assert.True(actualPort <= 65535, "Port should not exceed maximum valid port");
+    }
+
+    [Theory]
+    [InlineData(80)]
+    [InlineData(443)]
+    [InlineData(8080)]
+    [InlineData(42000)]
+    [InlineData(32767)]
+    [InlineData(32768)]
+    [InlineData(65535)]
+    public void IPv4_GetPort_ReturnsCorrectPort_ForAllValidPorts(ushort expectedPort)
+    {
+        var nativeIpV4Address = new SOCKADDR_IN
+        {
+            sin_family = ADDRESS_FAMILY.AF_INET,
+            sin_port = (ushort)IPAddress.HostToNetworkOrder((short)expectedPort)
+        };
+
+        var socketAddress = new SocketAddressIPv4(nativeIpV4Address);
+        var actualPort = socketAddress.GetPort();
+
+        Assert.Equal(expectedPort, actualPort);
+        Assert.True(actualPort >= 0, "Port should never be negative");
+        Assert.True(actualPort <= 65535, "Port should not exceed maximum valid port");
+    }
+}

src/Shared/HttpSys/NativeInterop/SocketAddress.cs

@@ -1,6 +1,7 @@
 // Licensed to the .NET Foundation under one or more agreements.
 // The .NET Foundation licenses this file to you under the MIT license.
 
+using System.Buffers.Binary;
 using System.Net;
 using Windows.Win32.Networking.WinSock;
 
@@ -25,7 +26,8 @@ internal abstract class SocketAddress
         };
     }
 
-    private sealed class SocketAddressIPv4 : SocketAddress
+    // internal for testing
+    internal sealed class SocketAddressIPv4 : SocketAddress
     {
         private readonly SOCKADDR_IN _sockaddr;
 
@@ -36,8 +38,9 @@ internal SocketAddressIPv4(in SOCKADDR_IN sockaddr)
 
         internal override int GetPort()
         {
-            // sin_port is network byte order
-            return IPAddress.NetworkToHostOrder((short)_sockaddr.sin_port);
+            // _sockaddr.sin_port has network byte order.
+            // cast to ushort is important to avoid negative values for the TCP port
+            return (ushort)IPAddress.NetworkToHostOrder((short)_sockaddr.sin_port);
         }
 
         internal override IPAddress? GetIPAddress()
@@ -47,7 +50,8 @@ internal override int GetPort()
         }
     }
 
-    private sealed class SocketAddressIPv6 : SocketAddress
+    // internal for testing
+    internal sealed class SocketAddressIPv6 : SocketAddress
     {
         private readonly SOCKADDR_IN6 _sockaddr;
 
@@ -58,8 +62,9 @@ internal SocketAddressIPv6(in SOCKADDR_IN6 sockaddr)
 
         internal override int GetPort()
         {
-            // sin6_port is network byte order
-            return IPAddress.NetworkToHostOrder((short)_sockaddr.sin6_port);
+            // _sockaddr.sin6_port has network byte order.
+            // cast to ushort is important to avoid negative values for the TCP port
+            return (ushort)IPAddress.NetworkToHostOrder((short)_sockaddr.sin6_port);
         }
 
         internal override IPAddress? GetIPAddress()