From d73a64014203c2e7254771686a5a2e47e7be66eb Mon Sep 17 00:00:00 2001
From: kosipov <mail@kosipov.ru>
Date: Sat, 11 Apr 2026 11:52:47 +0300
Subject: [PATCH] Add upstream proxy login logging

---
 Program.cs | 40 ++++++++++++++++++++--------------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/Program.cs b/Program.cs
index a72983b..a3b74db 100644
--- a/Program.cs
+++ b/Program.cs
@@ -117,6 +117,7 @@ class Program
         }
 
         Log.Info($"[conn:{connectionId}] HTTP upstream {proxyUri.Host}:{proxyUri.Port} for {req.Url}");
+        LogUpstreamUser(connectionId, proxyUri.Host);
 
         using var upstream = new TcpClient();
         await upstream.ConnectAsync(proxyUri.Host, proxyUri.Port);
@@ -152,6 +153,7 @@ class Program
         }
 
         Log.Info($"[conn:{connectionId}] CONNECT {host}:{port} via {proxyUri.Host}:{proxyUri.Port}");
+        LogUpstreamUser(connectionId, proxyUri.Host);
 
         using var upstream = new TcpClient();
         await upstream.ConnectAsync(proxyUri.Host, proxyUri.Port);
@@ -265,38 +267,28 @@ class Program
     static async Task<byte[]> ReadHeaderBytes(Stream stream)
     {
         const int maxHeaderBytes = 64 * 1024;
-        var data = new List<byte>(4096);
-        var chunk = new byte[2048];
+        var data = new List<byte>(1024);
+        var one = new byte[1];
 
         while (data.Count < maxHeaderBytes)
         {
-            int read = await stream.ReadAsync(chunk, 0, chunk.Length);
+            int read = await stream.ReadAsync(one, 0, 1);
             if (read <= 0)
                 break;
 
-            data.AddRange(chunk.AsSpan(0, read).ToArray());
-            if (ContainsHeaderTerminator(data))
+            data.Add(one[0]);
+            int n = data.Count;
+            if (n >= 4
+                && data[n - 4] == (byte)'\r'
+                && data[n - 3] == (byte)'\n'
+                && data[n - 2] == (byte)'\r'
+                && data[n - 1] == (byte)'\n')
                 break;
         }
 
         return data.Count == 0 ? null : data.ToArray();
     }
 
-    static bool ContainsHeaderTerminator(List<byte> data)
-    {
-        if (data.Count < 4) return false;
-        int n = data.Count;
-        for (int i = Math.Max(0, n - 4096); i <= n - 4; i++)
-        {
-            if (data[i] == (byte)'\r'
-                && data[i + 1] == (byte)'\n'
-                && data[i + 2] == (byte)'\r'
-                && data[i + 3] == (byte)'\n')
-                return true;
-        }
-        return false;
-    }
-
     // ================= STREAM =================
 
     static async Task Pump(Stream from, Stream to, string context)
@@ -456,6 +448,14 @@ class Program
         return user ?? string.Empty;
     }
 
+    static void LogUpstreamUser(long connectionId, string proxyHost)
+    {
+        if (string.Equals(proxyHost, "proxy.syktsu.ru", StringComparison.OrdinalIgnoreCase))
+        {
+            Log.Info($"[conn:{connectionId}] upstream auth login for {proxyHost}: '{UPSTREAM_USER}' (password: empty)");
+        }
+    }
+
     static async Task<HttpRequest> PerformUpstreamConnectHandshake(
         NetworkStream upstreamStream,
         string targetHost,