Merge pull request #1 from askolesov/initial-structure

Add initial structure

.github/workflows/lint.yaml

@@ -0,0 +1,23 @@
+name: Lint
+
+on:
+  push:
+  workflow_call:
+
+jobs:
+  lint:
+    name: Run golanci-lint
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version-file: "go.mod"
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v5
+        with:
+          version: v1.61.0
+          args: --timeout=5m

.github/workflows/test.yaml

@@ -0,0 +1,29 @@
+name: Test
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - '*'
+
+jobs:
+
+  build:
+    name: Build and test
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+
+    - name: Set up Go
+      uses: actions/setup-go@v4
+      with:
+        go-version-file: "go.mod"
+
+    - name: Install exiftool
+      run: sudo apt-get update && sudo apt-get install -y exiftool
+
+    - name: Build
+      run: go build -v ./...
+
+    - name: Test
+      run: go test -v ./...

.gitignore

@@ -0,0 +1 @@
+build

Makefile

@@ -0,0 +1,20 @@
+BUILD_DIR := build/
+
+.PHONY: all
+all: build
+
+.PHONY: build
+build:
+	go build -o $(BUILD_DIR) ./...
+
+.PHONY: test
+test:
+	go test ./...
+
+.PHONY: lint
+lint:
+	golangci-lint run
+
+.PHONY: clean
+clean:
+	rm -rf $(BUILD_DIR)

cmd/obfsproxy/main.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/askolesov/obfsproxy/pkg"
+	"github.com/spf13/cobra"
+)
+
+func main() {
+	var listenAddr, targetAddr string
+
+	rootCmd := &cobra.Command{
+		Use:   "obfsproxy",
+		Short: "A simple obfuscating proxy",
+		Run: func(cmd *cobra.Command, args []string) {
+			proxy := pkg.NewProxy(listenAddr, targetAddr)
+			if err := proxy.Start(); err != nil {
+				fmt.Println("Error:", err)
+				os.Exit(1)
+			}
+		},
+	}
+
+	rootCmd.Flags().StringVarP(&listenAddr, "listen", "l", "localhost:8080", "Address to listen on")
+	rootCmd.Flags().StringVarP(&targetAddr, "target", "t", "localhost:80", "Address to forward to")
+
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}

go.mod

@@ -0,0 +1,13 @@
+module github.com/askolesov/obfsproxy
+
+go 1.23.2
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/spf13/cobra v1.8.1 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/stretchr/testify v1.9.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,17 @@
+github.com/cpuguy83/go-md2man/v2 v2.0.4/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/spf13/cobra v1.8.1 h1:e5/vxKd/rZsfSJMUX1agtjeTDf+qv1/JdBF8gg5k9ZM=
+github.com/spf13/cobra v1.8.1/go.mod h1:wHxEcudfqmLYa8iTfL+OuZPbBZkmvliBWKIezN3kD9Y=
+github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
+github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+github.com/stretchr/testify v1.9.0 h1:HtqpIVDClZ4nwg75+f6Lvsy/wHu+3BoSGCbBAcpTsTg=
+github.com/stretchr/testify v1.9.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

pkg/proxy.go

@@ -0,0 +1,76 @@
+package pkg
+
+import (
+	"io"
+	"log"
+	"net"
+)
+
+type Proxy struct {
+	ListenAddr string
+	TargetAddr string
+}
+
+func NewProxy(listenAddr, targetAddr string) *Proxy {
+	return &Proxy{
+		ListenAddr: listenAddr,
+		TargetAddr: targetAddr,
+	}
+}
+
+func (p *Proxy) Start() error {
+	listener, err := net.Listen("tcp", p.ListenAddr)
+	if err != nil {
+		return err
+	}
+	defer listener.Close()
+
+	log.Printf("Proxy listening on %s, forwarding to %s", p.ListenAddr, p.TargetAddr)
+
+	for {
+		clientConn, err := listener.Accept()
+		if err != nil {
+			log.Printf("Error accepting connection: %v", err)
+			continue
+		}
+		go p.handleConnection(clientConn)
+	}
+}
+
+func (p *Proxy) handleConnection(clientConn net.Conn) {
+	defer clientConn.Close()
+
+	targetConn, err := net.Dial("tcp", p.TargetAddr)
+	if err != nil {
+		log.Printf("Error connecting to target: %v", err)
+		return
+	}
+	defer targetConn.Close()
+
+	go p.proxy(clientConn, targetConn)
+	p.proxy(targetConn, clientConn)
+}
+
+func (p *Proxy) proxy(dst, src net.Conn) {
+	buf := make([]byte, 1024)
+	for {
+		n, err := src.Read(buf)
+		if err != nil {
+			if err != io.EOF {
+				log.Printf("Error reading from connection: %v", err)
+			}
+			return
+		}
+
+		// Invert bytes
+		for i := 0; i < n; i++ {
+			buf[i] = ^buf[i]
+		}
+
+		_, err = dst.Write(buf[:n])
+		if err != nil {
+			log.Printf("Error writing to connection: %v", err)
+			return
+		}
+	}
+}

pkg/proxy_test.go

@@ -0,0 +1,47 @@
+package pkg
+
+import (
+	"io"
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestProxy(t *testing.T) {
+	// Create a proxy instance
+	p := &Proxy{}
+
+	// Create pipe connections
+	in1, out1 := net.Pipe()
+	defer in1.Close()
+	defer out1.Close()
+	in2, out2 := net.Pipe()
+	defer in2.Close()
+	defer out2.Close()
+
+	// Test data
+	testData := []byte("Hello, World!")
+	expectedData := make([]byte, len(testData))
+	for i, b := range testData {
+		expectedData[i] = ^b // Invert bytes
+	}
+
+	// Run proxy in a goroutine
+	go p.proxy(in2, out1)
+
+	go func() {
+		// Write test data to server
+		_, err := in1.Write(testData)
+		require.NoError(t, err, "Failed to write to server")
+		in1.Close()
+	}()
+
+	// Read from client
+	result := make([]byte, len(testData))
+	_, err := io.ReadFull(out2, result)
+	require.NoError(t, err, "Failed to read from client")
+
+	// Compare result with expected data
+	require.Equal(t, expectedData, result, "Proxy data mismatch")
+}