Change HTTPS proxy to work off redirects towards an external proxy (#668

)

This allows us to use an external proxy, instead of the buggy proxy that
I had originally written. Sadly we cant redirect directly to prod
because of a bug in the original game (after a redirect it still uses
the pre-redirect host header value with the new server).

In practice, the proxy.json config will probably just point to the same
machine as Refresh.HttpsProxy itself, but with a different port, which
is hosting a standard nginx HTTP proxy server.

This PR also fixes the middleware order

Refresh.Common/Extensions/NameValueCollectionExtensions.cs

@@ -0,0 +1,36 @@
+using System.Collections.Specialized;
+using System.Text;
+using System.Web;
+
+namespace Refresh.Common.Extensions;
+
+public static class NameValueCollectionExtensions
+{
+    public static string ToQueryString(this NameValueCollection queryParams)
+    {
+        StringBuilder builder = new();
+
+        if (queryParams.Count == 0)
+            return string.Empty;
+
+        builder.Append('?');
+        for (int i = 0; i < queryParams.Count; i++)
+        {
+            string? key = queryParams.GetKey(i);
+            string? val = queryParams.Get(i);
+
+            if (key == null)
+                continue;
+
+            builder.Append(HttpUtility.UrlEncode(key));
+            builder.Append('=');
+            if(val != null)
+                builder.Append(HttpUtility.UrlEncode(val));
+
+            if(i < queryParams.Count - 1)
+                builder.Append('&');
+        }
+
+        return builder.ToString();
+    }
+}

Refresh.GameServer/Middlewares/DigestMiddleware.cs

@@ -117,9 +117,15 @@ public void HandleRequest(ListenerContext context, Lazy<IDatabaseContext> databa
         }
 
         // If the client asks for a particular digest index, use that digest
-        if (int.TryParse(context.RequestHeaders["Refresh-Ps3-Digest-Index"], out int ps3DigestIndex) && 
-            int.TryParse(context.RequestHeaders["Refresh-Ps4-Digest-Index"], out int ps4DigestIndex))
+        if (int.TryParse(context.Query["force_ps3_digest"], out int ps3DigestIndex) && 
+            int.TryParse(context.Query["force_ps4_digest"], out int ps4DigestIndex))
         {
+            if (ps3DigestIndex >= this._config.Sha1DigestKeys.Length)
+                ps3DigestIndex = 0;
+
+            if (ps4DigestIndex >= this._config.HmacDigestKeys.Length)
+                ps4DigestIndex = 0;
+
             string digest = isPs4
                 ? this._config.HmacDigestKeys[ps4DigestIndex]
                 : this._config.Sha1DigestKeys[ps3DigestIndex];
@@ -128,7 +134,7 @@ public void HandleRequest(ListenerContext context, Lazy<IDatabaseContext> databa
 
             if(token != null)
                 gameDatabase.SetTokenDigestInfo(token, digest, isPs4);
-
+        
             return;
         }
 

Refresh.GameServer/RefreshGameServer.cs

@@ -94,11 +94,11 @@ protected override void SetupMiddlewares()
     {
         this.Server.AddMiddleware<WebsiteMiddleware>();
         this.Server.AddMiddleware(new DeflateMiddleware(this._config!));
+        this.Server.AddMiddleware<LegacyAdapterMiddleware>();
         // Digest middleware must be run before LegacyAdapterMiddleware, because digest is based on the raw route, not the fixed route
         this.Server.AddMiddleware(new DigestMiddleware(this._config!));
         this.Server.AddMiddleware<CrossOriginMiddleware>();
         this.Server.AddMiddleware<PspVersionMiddleware>();
-        this.Server.AddMiddleware<LegacyAdapterMiddleware>();
         this.Server.AddMiddleware(new PresenceAuthenticationMiddleware(this._integrationConfig!));
     }
 

Refresh.HttpsProxy/Middlewares/RedirectMiddleware.cs

@@ -0,0 +1,27 @@
+using System.Net;
+using Bunkum.Core.Database;
+using Bunkum.Core.Endpoints.Middlewares;
+using Bunkum.Listener.Request;
+using Refresh.Common.Extensions;
+using Refresh.HttpsProxy.Config;
+
+namespace Refresh.HttpsProxy.Middlewares;
+
+public class RedirectMiddleware(ProxyConfig config) : IMiddleware
+{
+    public void HandleRequest(ListenerContext context, Lazy<IDatabaseContext> database, Action next)
+    {
+        UriBuilder uri = new(config.TargetServerUrl)
+        {
+            Path = context.Uri.AbsolutePath,
+        };
+
+        context.Query["force_ps3_digest"] = config.Ps3DigestIndex.ToString();
+        context.Query["force_ps4_digest"] = config.Ps4DigestIndex.ToString();
+
+        uri.Query = context.Query.ToQueryString();
+
+        context.ResponseCode = HttpStatusCode.TemporaryRedirect;
+        context.ResponseHeaders["Location"] = uri.ToString();
+    }
+}

Refresh.HttpsProxy/Program.cs

@@ -26,7 +26,7 @@
 Action<BunkumServer> initialize = s =>
 {
     ProxyConfig config = Config.LoadFromJsonFile<ProxyConfig>("proxy.json", s.Logger);
-    s.AddMiddleware(new ProxyMiddleware(config));
+    s.AddMiddleware(new RedirectMiddleware(config));
 };
 
 httpsServer.Initialize = initialize;

RefreshTests.GameServer/Tests/Middlewares/DigestMiddlewareTests.cs

@@ -123,16 +123,13 @@ public void DigestSelectionHeaderWorks(bool isHmac)
 
         string serverDigest = DigestMiddleware.CalculateDigest(digest, endpoint, Encoding.ASCII.GetBytes(expectedResultStr), "", null, false, isHmac);
 
-        context.Http.DefaultRequestHeaders.Add("Refresh-Ps3-Digest-Index", "1");
-        context.Http.DefaultRequestHeaders.Add("Refresh-Ps4-Digest-Index", "1");
-
         // TODO: once we model PS4 clients in our tokens, make the request come from an authenticated PS4 client.
         if(isHmac)
             context.Http.DefaultRequestHeaders.TryAddWithoutValidation("User-Agent", "MM CHTTPClient LBP3 01.26");
 
         // send a blank digest to make it have to guess
         context.Http.DefaultRequestHeaders.Add("X-Digest-A", "");
-        HttpResponseMessage response =  context.Http.GetAsync(endpoint).Result;
+        HttpResponseMessage response =  context.Http.GetAsync(endpoint + "?force_ps3_digest=1&force_ps4_digest=1").Result;
 
         Assert.Multiple(() =>
         {