From 597af24edb6b670c961b85c860cde7e2ca4e09d1 Mon Sep 17 00:00:00 2001
From: ReinforceZwei <39955851+ReinforceZwei@users.noreply.github.com>
Date: Fri, 2 Dec 2022 21:15:05 +0800
Subject: [PATCH] ProxiedWebRequest: Support http/1.1 (#2357)

* ProxiedWebRequest: Support http/1.1

- Support chunked transfer
- Refactor the code

* Check cookie expire
---
 MinecraftClient/Protocol/ProxiedWebRequest.cs | 330 ++++++++++++++----
 1 file changed, 262 insertions(+), 68 deletions(-)

diff --git a/MinecraftClient/Protocol/ProxiedWebRequest.cs b/MinecraftClient/Protocol/ProxiedWebRequest.cs
index 73d9fe26..1e028abb 100644
--- a/MinecraftClient/Protocol/ProxiedWebRequest.cs
+++ b/MinecraftClient/Protocol/ProxiedWebRequest.cs
@@ -1,12 +1,14 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.Specialized;
+using System.Linq;
 using System.Globalization;
 using System.IO;
 using System.Net.Security;
 using System.Net.Sockets;
 using System.Security.Authentication;
 using System.Text;
+using System.Threading;
 using MinecraftClient.Proxy;
 
 namespace MinecraftClient.Protocol
@@ -16,12 +18,21 @@ namespace MinecraftClient.Protocol
     /// </summary>
     public class ProxiedWebRequest
     {
-        private readonly string httpVersion = "HTTP/1.0"; // Use 1.0 here because 1.1 server may send chunked data
+        public interface ITcpFactory
+        {
+            TcpClient CreateTcpClient(string host, int port);
+        };
+
+        private readonly string httpVersion = "HTTP/1.1";
+
+        private ITcpFactory? tcpFactory;
+        private bool isProxied = false; // Send absolute Url in request if true
 
         private readonly Uri uri;
         private string Host { get { return uri.Host; } }
         private int Port { get { return uri.Port; } }
         private string Path { get { return uri.PathAndQuery; } }
+        private string AbsoluteUrl { get { return uri.AbsoluteUri; } }
         private bool IsSecure { get { return uri.Scheme == "https"; } }
 
         public NameValueCollection Headers = new();
@@ -30,6 +41,12 @@ namespace MinecraftClient.Protocol
         public string Accept { get { return Headers.Get("Accept") ?? String.Empty; } set { Headers.Set("Accept", value); } }
         public string Cookie { set { Headers.Set("Cookie", value); } }
 
+        /// <summary>
+        /// Set to true to tell the http client proxy is enabled
+        /// </summary>
+        public bool IsProxy { get { return isProxied; } set { isProxied = value; } }
+        public bool Debug { get { return Settings.Config.Logging.DebugMessages; } }
+
         /// <summary>
         /// Create a new http request
         /// </summary>
@@ -52,13 +69,34 @@ namespace MinecraftClient.Protocol
             SetupBasicHeaders();
         }
 
+        /// <summary>
+        /// Create a new http request with custom tcp client
+        /// </summary>
+        /// <param name="tcpFactory">Tcp factory to be used</param>
+        /// <param name="url">Target URL</param>
+        public ProxiedWebRequest(ITcpFactory tcpFactory, string url) : this(url)
+        {
+            this.tcpFactory = tcpFactory;
+        }
+
+        /// <summary>
+        /// Create a new http request with custom tcp client and cookies
+        /// </summary>
+        /// <param name="tcpFactory">Tcp factory to be used</param>
+        /// <param name="url">Target URL</param>
+        /// <param name="cookies">Cookies to use</param>
+        public ProxiedWebRequest(ITcpFactory tcpFactory, string url, NameValueCollection cookies) : this(url, cookies)
+        {
+            this.tcpFactory = tcpFactory;
+        }
+
         /// <summary>
         /// Setup some basic headers
         /// </summary>
         private void SetupBasicHeaders()
         {
             Headers.Add("Host", Host);
-            Headers.Add("User-Agent", "MCC/" + Program.Version);
+            Headers.Add("User-Agent", "MCC/1.0");
             Headers.Add("Accept", "*/*");
             Headers.Add("Connection", "close");
         }
@@ -96,7 +134,7 @@ namespace MinecraftClient.Protocol
         {
             List<string> requestMessage = new()
             {
-                string.Format("{0} {1} {2}", method.ToUpper(), Path, httpVersion) // Request line
+                string.Format("{0} {1} {2}", method.ToUpper(), isProxied ? AbsoluteUrl : Path, httpVersion) // Request line
             };
             foreach (string key in Headers) // Headers
             {
@@ -109,7 +147,7 @@ namespace MinecraftClient.Protocol
                 requestMessage.Add(body);
             }
             else requestMessage.Add(""); // <CR><LF>
-            if (Settings.Config.Logging.DebugMessages)
+            if (Debug)
             {
                 foreach (string l in requestMessage)
                 {
@@ -117,84 +155,240 @@ namespace MinecraftClient.Protocol
                 }
             }
             Response response = Response.Empty();
-            AutoTimeout.Perform(() =>
+
+            // FIXME: Use TcpFactory interface to avoid direct usage of the ProxyHandler class
+            // TcpClient client = tcpFactory.CreateTcpClient(Host, Port);
+            TcpClient client = ProxyHandler.NewTcpClient(Host, Port, true);
+            Stream stream;
+            if (IsSecure)
             {
-                TcpClient client = ProxyHandler.NewTcpClient(Host, Port, true);
-                Stream stream;
-                if (IsSecure)
-                {
-                    stream = new SslStream(client.GetStream());
-                    ((SslStream)stream).AuthenticateAsClient(Host, null, SslProtocols.Tls12, true); // Enable TLS 1.2. Hotfix for #1774
-                }
-                else
-                {
-                    stream = client.GetStream();
-                }
-                string h = string.Join("\r\n", requestMessage.ToArray());
-                byte[] data = Encoding.ASCII.GetBytes(h);
-                stream.Write(data, 0, data.Length);
-                stream.Flush();
-                StreamReader sr = new(stream);
-                string rawResult = sr.ReadToEnd();
-                response = ParseResponse(rawResult);
-                try
-                {
-                    sr.Close();
-                    stream.Close();
-                    client.Close();
-                }
-                catch { }
-            },
-            TimeSpan.FromSeconds(30));
+                stream = new SslStream(client.GetStream());
+                ((SslStream)stream).AuthenticateAsClient(Host, null, SslProtocols.Tls12, true); // Enable TLS 1.2. Hotfix for #1774
+            }
+            else
+            {
+                stream = client.GetStream();
+            }
+            string h = string.Join("\r\n", requestMessage.ToArray());
+            byte[] data = Encoding.ASCII.GetBytes(h);
+            stream.Write(data, 0, data.Length);
+            stream.Flush();
+
+            // Read response
+            int statusCode = ReadHttpStatus(stream);
+            var headers = ReadHeader(stream);
+            string? rbody;
+            if (headers.Get("transfer-encoding") == "chunked")
+            {
+                rbody = ReadBodyChunked(stream);
+            }
+            else
+            {
+                rbody = ReadBody(stream, int.Parse(headers.Get("content-length") ?? "0"));
+            }
+            if (headers.Get("set-cookie") != null)
+            {
+                response.Cookies = ParseSetCookie(headers.GetValues("set-cookie") ?? Array.Empty<string>());
+            }
+            response.Body = rbody ?? "";
+            response.StatusCode = statusCode;
+            response.Headers = headers;
+            
+            try
+            {
+                stream.Close();
+                client.Close();
+            }
+            catch { }
+
             return response;
         }
 
         /// <summary>
-        /// Parse a raw response string to response object
+        /// Read HTTP response line from a Stream
         /// </summary>
-        /// <param name="raw">raw response string</param>
+        /// <param name="s">Stream to read</param>
         /// <returns></returns>
-        private Response ParseResponse(string raw)
+        /// <exception cref="InvalidDataException">If server return unknown data</exception>
+        private static int ReadHttpStatus(Stream s)
         {
-            int statusCode;
-            string responseBody = "";
-            NameValueCollection headers = new();
-            NameValueCollection cookies = new();
-            if (raw.StartsWith("HTTP/1.1") || raw.StartsWith("HTTP/1.0"))
+            var httpHeader = ReadLine(s); // http header line
+            if (httpHeader.StartsWith("HTTP/1.1") || httpHeader.StartsWith("HTTP/1.0"))
             {
-                Queue<string> msg = new(raw.Split(new string[] { "\r\n" }, StringSplitOptions.None));
-                statusCode = int.Parse(msg.Dequeue().Split(' ')[1], NumberStyles.Any, CultureInfo.CurrentCulture);
-
-                while (msg.Peek() != "")
-                {
-                    string[] header = msg.Dequeue().Split(new char[] { ':' }, 2); // Split first ':' only
-                    string key = header[0].ToLower(); // Key is case-insensitive
-                    string value = header[1];
-                    if (key == "set-cookie")
-                    {
-                        string[] cookie = value.Split(';'); // cookie options are ignored
-                        string[] tmp = cookie[0].Split(new char[] { '=' }, 2); // Split first '=' only
-                        string cname = tmp[0].Trim();
-                        string cvalue = tmp[1].Trim();
-                        cookies.Add(cname, cvalue);
-                    }
-                    else
-                    {
-                        headers.Add(key, value.Trim());
-                    }
-                }
-                msg.Dequeue();
-                if (msg.Count > 0)
-                    responseBody = msg.Dequeue();
-
-                return new Response(statusCode, responseBody, headers, cookies);
+                return int.Parse(httpHeader.Split(' ')[1], NumberStyles.Any, CultureInfo.CurrentCulture);
             }
             else
             {
-                return new Response(520 /* Web Server Returned an Unknown Error */, "", headers, cookies);
+                throw new InvalidDataException("Unexpect data from server");
             }
         }
 
+        /// <summary>
+        /// Read HTTP headers from a Stream
+        /// </summary>
+        /// <param name="s">Stream to read</param>
+        /// <returns>Headers in lower-case</returns>
+        private static NameValueCollection ReadHeader(Stream s)
+        {
+            var headers = new NameValueCollection();
+            // Read headers
+            string header;
+            do
+            {
+                header = ReadLine(s);
+                if (!String.IsNullOrEmpty(header))
+                {
+                    var tmp = header.Split(new char[] { ':' }, 2);
+                    var name = tmp[0].ToLower();
+                    var value = tmp[1].Trim();
+                    headers.Add(name, value);
+                }
+            }
+            while (!String.IsNullOrEmpty(header));
+            return headers;
+        }
+
+        /// <summary>
+        /// Read HTTP body from a Stream
+        /// </summary>
+        /// <param name="s">Stream to read</param>
+        /// <param name="length">Length of the body (the Content-Length header)</param>
+        /// <returns>Body or null if length is zero</returns>
+        private static string? ReadBody(Stream s, int length)
+        {
+            if (length > 0)
+            {
+                byte[] buffer = new byte[length];
+                int r = 0;
+                while (r < length)
+                {
+                    var read = s.Read(buffer, r, length - r);
+                    r += read;
+                    Thread.Sleep(50);
+                }
+                return Encoding.UTF8.GetString(buffer);
+            }
+            else
+            {
+                return null;
+            }
+        }
+
+        /// <summary>
+        /// Read HTTP chunked body from a Stream
+        /// </summary>
+        /// <param name="s">Stream to read</param>
+        /// <returns>Body or empty string if nothing is received</returns>
+        private static string ReadBodyChunked(Stream s)
+        {
+            List<byte> buffer1 = new();
+            while (true)
+            {
+                string l = ReadLine(s);
+                int size = Int32.Parse(l, NumberStyles.HexNumber);
+                if (size == 0)
+                    break;
+                byte[] buffer2 = new byte[size];
+                int r = 0;
+                while (r < size)
+                {
+                    var read = s.Read(buffer2, r, size - r);
+                    r += read;
+                    Thread.Sleep(50);
+                }
+                ReadLine(s);
+                buffer1.AddRange(buffer2);
+            }
+            return Encoding.UTF8.GetString(buffer1.ToArray());
+        }
+
+        /// <summary>
+        /// Parse the Set-Cookie header value into NameValueCollection. Cookie options are ignored
+        /// </summary>
+        /// <param name="headerValue">Array of value strings</param>
+        /// <returns>Parsed cookies</returns>
+        private static NameValueCollection ParseSetCookie(IEnumerable<string> headerValue)
+        {
+            NameValueCollection cookies = new();
+            foreach (var value in headerValue)
+            {
+                string[] cookie = value.Split(';'); // cookie options are ignored
+                string[] tmp = cookie[0].Split(new char[] { '=' }, 2); // Split first '=' only
+                string[] options = cookie[1..];
+                string cname = tmp[0].Trim();
+                string cvalue = tmp[1].Trim();
+                // Check expire
+                bool isExpired = false;
+                foreach (var option in options)
+                {
+                    var tmp2 = option.Trim().Split(new char[] { '=' }, 2);
+                    // Check for Expires=<date> and Max-Age=<number>
+                    if (tmp2.Length == 2)
+                    {
+                        var optName = tmp2[0].Trim().ToLower();
+                        var optValue = tmp2[1].Trim();
+                        switch (optName)
+                        {
+                            case "expires":
+                                {
+                                    if (DateTime.TryParse(optValue, out var expDate))
+                                    {
+                                        if (expDate < DateTime.Now)
+                                            isExpired = true;
+                                    }
+                                    break;
+                                }
+                            case "max-age":
+                                {
+                                    if (int.TryParse(optValue, out var expInt))
+                                    {
+                                        if (expInt <= 0)
+                                            isExpired = true;
+                                    }
+                                    break;
+                                }
+                        }
+                    }
+                    if (isExpired)
+                        break;
+                }
+                if (!isExpired)
+                    cookies.Add(cname, cvalue);
+            }
+            return cookies;
+        }
+
+        /// <summary>
+        /// Read a line from a Stream
+        /// </summary>
+        /// <remarks>
+        /// Line break by \r\n and they are not included in returned string
+        /// </remarks>
+        /// <param name="s">Stream to read</param>
+        /// <returns>String</returns>
+        private static string ReadLine(Stream s)
+        {
+            List<byte> buffer = new();
+            byte c;
+            while (true)
+            {
+                int b = s.ReadByte();
+                if (b == -1)
+                    break;
+                c = (byte)b;
+                if (c == '\n')
+                {
+                    if (buffer.Last() == '\r')
+                    {
+                        buffer.RemoveAt(buffer.Count - 1);
+                        break;
+                    }
+                }
+                buffer.Add(c);
+            }
+            return Encoding.UTF8.GetString(buffer.ToArray());
+        }
+
         /// <summary>
         /// Get the cookie string representation to use in header
         /// </summary>
@@ -271,4 +465,4 @@ namespace MinecraftClient.Protocol
             }
         }
     }
-}
+}
\ No newline at end of file