tcp-relay

Author: lxrite

.gitignore

@@ -9,3 +9,4 @@ install_manifest.txt
 compile_commands.json
 CTestTestfile.cmake
 _deps
+.vscode

.gitmodules

@@ -0,0 +1,6 @@
+[submodule "third_party/asio"]
+	path = third_party/asio
+	url = https://github.com/chriskohlhoff/asio.git
+[submodule "third_party/fmt"]
+	path = third_party/fmt
+	url = https://github.com/fmtlib/fmt.git

CMakeLists.txt

@@ -0,0 +1,38 @@
+cmake_minimum_required(VERSION 3.1)
+project(tcp-relay)
+
+option(USE_STD_FORMAT                "Use std::format instead of fmt::format" OFF)
+
+set(CMAKE_CXX_STANDARD 20)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+if(NOT CMAKE_BUILD_TYPE)
+  set(CMAKE_BUILD_TYPE Release)
+endif()
+
+add_definitions(-DASIO_STANDALONE)
+
+set(ASIO_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/third_party/asio/asio/include)
+
+include_directories(${ASIO_INCLUDE_DIR})
+
+if (USE_STD_FORMAT)
+  add_definitions(-DUSE_STD_FORMAT)
+else()
+  add_definitions(-DFMT_HEADER_ONLY=1)
+  set(FMT_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/third_party/fmt/include)
+  include_directories(${FMT_INCLUDE_DIR})
+endif()
+
+if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+  if (CMAKE_CXX_COMPILER MATCHES ".*musl\\-g\\+\\+.*")
+    # fix openwrt build issue
+    add_definitions(-DASIO_HAS_CO_AWAIT=1)
+    add_definitions(-DASIO_HAS_STD_COROUTINE=1)
+  endif()
+endif()
+
+add_executable(tcp-relay src/tcp_relay.cpp)
+if("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+  target_compile_options(tcp-relay PRIVATE -fcoroutines)
+endif()

Dockerfile

@@ -0,0 +1,17 @@
+FROM alpine:3.18 as builder
+
+RUN apk update \
+    && apk add alpine-sdk cmake linux-headers
+
+WORKDIR /ahp
+
+COPY . .
+
+RUN cmake -B build -DCMAKE_BUILD_TYPE=Release \
+    && cmake --build build
+
+FROM alpine:3.18
+
+RUN apk update && apk add libgcc libstdc++
+
+COPY --from=builder /ahp/build/tcp-relay /usr/local/bin/tcp-relay

README.md

@@ -0,0 +1,64 @@
+# TCP-Relay
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue)](LICENSE)
+
+A high-performance and easy-to-use TCP-Relay write in C++20 based on [AISO](https://think-async.com/Asio/) and [Coroutines](https://en.cppreference.com/w/cpp/language/coroutines). In addition to basic TCP relay, it also supports relaying through intermediate proxies (such as HTTP-Proxy).
+
+# Getting Started
+## Build from source
+This project relies on some C++20 features. The following compilers and their respective versions are supported:
+- GCC >= 12.0
+- Clang >= 14.0
+- Microsoft Visual Studio (MSVC) >= 2019
+
+``` bash
+# clone
+git clone --recursive https://github.com/lxrite/tcp-relay.git
+cd tcp-relay
+
+# build
+cmake -B build -DCMAKE_BUILD_TYPE=Release
+cmake --build build
+```
+
+## Usage
+``` bash
+$ ./tcp-relay --help
+Usage: tcp-relay [options]
+
+options:
+  -h, --help                  Show this help message and exit
+  -v, --version               Print the program version and exit
+  -l, --listen_addr string    Local address to listen on (default: 0.0.0.0)
+  -p, --port number           Local port to listen on (default: 8886)
+  -t, --target string         Taget address (host:port) to connect
+  --timeout number            Connection timeout (in seconds) (default: 240)
+  --via [none | http_proxy]   Transfer via other proxy (default: none)
+  --http_proxy string         HTTP-Proxy address (host:port)
+  --log_level string [trace | debug | info | warn | error | disable] Log level (default: info)
+```
+
+## Examples
+``` bash
+# basic
+./tcp-relay -t 172.16.1.1:8080
+
+# IPv6
+./tcp-relay -t [fd12:3456:789a:bcde::1]:8080
+
+# domain
+./tcp-relay -t example.com:8080
+
+# relay through HTTP intermediate proxy
+./tcp-relay -t example.com:8080 --via http_proxy --http_proxy proxy.example.com:1234
+```
+
+## Using Docker
+``` bash
+# build from local Dockerfile
+docker build -t lxrite/tcp-relay .
+# build from URL
+docker build -t lxrite/tcp-relay https://github.com/lxrite/tcp-relay.git
+
+# run
+docker run -d -p 8886:8886 lxrite/tcp-relay tcp-relay -t 172.16.1.1:8080
+```