refactor: move outline-ss-server to cmd/ and hide code (Jigsaw-Code#136)

- Moves the binary to the standard `cmd` directory, and paves the way for having more binaries.
- Hides internal code to prevent external dependencies.

.gitignore

@@ -21,3 +21,6 @@
 
 # Git submodules
 /third_party/maxmind/
+
+# Prometheus
+/data/

.goreleaser.yml

@@ -18,6 +18,7 @@ project_name: outline-ss-server
 # Skip 32 bit macOS builds.
 builds:
   -
+    main: ./cmd/outline-ss-server/main.go
     env:
       - CGO_ENABLED=0
     goos:

Makefile

@@ -1,14 +1,13 @@
 BUILDDIR=$(CURDIR)/dist
-GOBIN=$(CURDIR)/bin
-GORELEASER=$(GOBIN)/goreleaser
+GORELEASER=go run github.com/goreleaser/goreleaser
 
 .PHONY: release release-local test clean clean-all
 
 # This requires GITHUB_TOKEN to be set.
-release: clean-all $(GORELEASER)
+release: clean-all
 	$(GORELEASER)
 
-release-local: $(GORELEASER)
+release-local:
 	$(GORELEASER) --rm-dist --snapshot
 
 test: third_party/maxmind/test-data/GeoIP2-Country-Test.mmdb
@@ -17,9 +16,6 @@ test: third_party/maxmind/test-data/GeoIP2-Country-Test.mmdb
 third_party/maxmind/test-data/GeoIP2-Country-Test.mmdb:
 	git submodule update --init
 
-$(GORELEASER): go.mod
-	env GOBIN=$(GOBIN) go install github.com/goreleaser/goreleaser
-
 go.mod: tools.go
 	go mod tidy
 	touch go.mod
@@ -30,4 +26,3 @@ clean:
 
 clean-all: clean
 	rm -rf $(CURDIR)/third_party/maxmind/*
-	rm -rf $(GOBIN)

README.md

@@ -1,6 +1,9 @@
 # Outline ss-server
 
 ![Build Status](https://github.com/Jigsaw-Code/outline-ss-server/actions/workflows/go.yml/badge.svg)
+[![Go Report Card](https://goreportcard.com/badge/github.com/Jigsaw-Code/outline-ss-server)](https://goreportcard.com/report/github.com/Jigsaw-Code/outline-ss-server)
+[![Go Reference](https://pkg.go.dev/badge/github.com/Jigsaw-Code/outline-ss-server.svg)](https://pkg.go.dev/github.com/Jigsaw-Code/outline-ss-server)
+
 [![Mattermost](https://badgen.net/badge/Mattermost/Outline%20Community/blue)](https://community.internetfreedomfestival.org/community/channels/outline-community)
 [![Reddit](https://badgen.net/badge/Reddit/r%2Foutlinevpn/orange)](https://www.reddit.com/r/outlinevpn/)
 
@@ -22,29 +25,29 @@ The Outline Shadowsocks service allows for:
 
 Fetch dependencies for this demo:
 ```
-GO111MODULE=off go get github.com/shadowsocks/go-shadowsocks2 github.com/prometheus/prometheus/cmd/...
+GO111MODULE=off go get github.com/prometheus/prometheus/cmd/...
 ```
-If that doesn't work, download the [prometheus](https://prometheus.io/download/) or [go-shadowsocks2](https://github.com/shadowsocks/go-shadowsocks2/releases) binaries directly.
+If that doesn't work, download the [prometheus](https://prometheus.io/download/) binary directly.
 
 
 ### Run the server
 On Terminal 1, from the repository directory, build and start the SS server:
 ```
-go run . -config config_example.yml -metrics localhost:9091 --replay_history=10000
+go run ./cmd/outline-ss-server -config cmd/outline-ss-server/config_example.yml -metrics localhost:9091 --replay_history=10000
 ```
 In production, you may want to specify `-ip_country_db` to get per-country metrics. See [how the Outline Server calls outline-ss-server](https://github.com/Jigsaw-Code/outline-server/blob/master/src/shadowbox/server/outline_shadowsocks_server.ts).
 
 
 ### Run the Prometheus scraper for metrics collection
 On Terminal 2, start prometheus scraper for metrics collection:
 ```
-$(go env GOPATH)/bin/prometheus --config.file=prometheus_example.yml
+$(go env GOPATH)/bin/prometheus --config.file=cmd/outline-ss-server/prometheus_example.yml
 ```
 
 ### Run the SOCKS-to-Shadowsocks client
 On Terminal 3, start the SS client:
 ```
-$(go env GOPATH)/bin/go-shadowsocks2 -c ss://chacha20-ietf-poly1305:Secret0@:9000 -verbose  -socks localhost:1080
+go run github.com/shadowsocks/go-shadowsocks2 -c ss://chacha20-ietf-poly1305:Secret0@:9000 -verbose  -socks localhost:1080
 ```
 
 ### Fetch a page over Shadowsocks
@@ -70,12 +73,12 @@ iperf3 -s
 
 Start the SS server (listening on port 9000):
 ```
-go run . -config config_example.yml
+go run ./cmd/outline-ss-server -config cmd/outline-ss-server/config_example.yml
 ```
 
 Start the SS tunnel to redirect port 8000 -> localhost:5201 via the proxy on 9000:
 ```
-$(go env GOPATH)/bin/go-shadowsocks2 -c ss://chacha20-ietf-poly1305:Secret0@:9000 -tcptun ":8000=localhost:5201" -udptun ":8000=localhost:5201" -verbose
+go run github.com/shadowsocks/go-shadowsocks2 -c ss://chacha20-ietf-poly1305:Secret0@:9000 -tcptun ":8000=localhost:5201" -udptun ":8000=localhost:5201" -verbose
 ```
 
 Test TCP upload (client -> server):
@@ -102,7 +105,7 @@ iperf3 -c localhost -p 8000 --udp -b 0 --reverse
 
 Run the commands above, but start the SS server with
 ```
-$(go env GOPATH)/bin/go-shadowsocks2 -s ss://chacha20-ietf-poly1305:Secret0@:9000 -verbose
+go run github.com/shadowsocks/go-shadowsocks2 -s ss://chacha20-ietf-poly1305:Secret0@:9000 -verbose
 ```
 
 

client/client.go

@@ -6,9 +6,9 @@ import (
 	"net"
 	"time"
 
+	"github.com/Jigsaw-Code/outline-ss-server/internal/slicepool"
 	onet "github.com/Jigsaw-Code/outline-ss-server/net"
 	ss "github.com/Jigsaw-Code/outline-ss-server/shadowsocks"
-	"github.com/Jigsaw-Code/outline-ss-server/slicepool"
 	"github.com/shadowsocks/go-shadowsocks2/socks"
 )
 
@@ -156,7 +156,7 @@ func (c *packetConn) ReadFrom(b []byte) (int, net.Addr, error) {
 	if socksSrcAddr == nil {
 		return 0, nil, errors.New("Failed to read source address")
 	}
-	srcAddr := NewAddr(socksSrcAddr.String(), "udp")
+	srcAddr := newAddr(socksSrcAddr.String(), "udp")
 	n = copy(b, buf[len(socksSrcAddr):]) // Strip the SOCKS source address
 	if len(b) < len(buf)-len(socksSrcAddr) {
 		return n, srcAddr, io.ErrShortBuffer
@@ -177,8 +177,8 @@ func (a *addr) Network() string {
 	return a.network
 }
 
-// NewAddr returns a net.Addr that holds an address of the form `host:port` with a domain name or IP as host.
+// newAddr returns a net.Addr that holds an address of the form `host:port` with a domain name or IP as host.
 // Used for SOCKS addressing.
-func NewAddr(address, network string) net.Addr {
+func newAddr(address, network string) net.Addr {
 	return &addr{address: address, network: network}
 }

client/client_test.go

@@ -176,7 +176,7 @@ func TestShadowsocksClient_ListenUDP(t *testing.T) {
 	}
 	defer conn.Close()
 	conn.SetReadDeadline(time.Now().Add(time.Second * 5))
-	pcrw := &packetConnReadWriter{PacketConn: conn, targetAddr: NewAddr(testTargetAddr, "udp")}
+	pcrw := &packetConnReadWriter{PacketConn: conn, targetAddr: newAddr(testTargetAddr, "udp")}
 	expectEchoPayload(pcrw, ss.MakeTestPayload(1024), make([]byte, 1024), t)
 
 	proxy.Close()
@@ -236,7 +236,7 @@ func BenchmarkShadowsocksClient_ListenUDP(b *testing.B) {
 	buf := make([]byte, clientUDPBufferSize)
 	for n := 0; n < b.N; n++ {
 		payload := ss.MakeTestPayload(1024)
-		pcrw := &packetConnReadWriter{PacketConn: conn, targetAddr: NewAddr(testTargetAddr, "udp")}
+		pcrw := &packetConnReadWriter{PacketConn: conn, targetAddr: newAddr(testTargetAddr, "udp")}
 		b.StartTimer()
 		expectEchoPayload(pcrw, payload, buf, b)
 		b.StopTimer()

service/cipher_list.go

@@ -37,7 +37,7 @@ type CipherEntry struct {
 // MakeCipherEntry constructs a CipherEntry.
 func MakeCipherEntry(id string, cipher *ss.Cipher, secret string) CipherEntry {
 	var saltGenerator ServerSaltGenerator
-	if cipher.SaltSize()-ServerSaltMarkLen >= minSaltEntropy {
+	if cipher.SaltSize()-serverSaltMarkLen >= minSaltEntropy {
 		// Mark salts with a tag for reverse replay protection.
 		saltGenerator = NewServerSaltGenerator(secret)
 	} else {

service/server_salt.go

@@ -56,10 +56,10 @@ type serverSaltGenerator struct {
 	key []byte
 }
 
-// ServerSaltMarkLen is the number of bytes of salt to use as a marker.
+// serverSaltMarkLen is the number of bytes of salt to use as a marker.
 // Increasing this value reduces the false positive rate, but increases
 // the likelihood of salt collisions.
-const ServerSaltMarkLen = 4 // Must be less than or equal to SHA1.Size()
+const serverSaltMarkLen = 4 // Must be less than or equal to SHA1.Size()
 
 // Constant to identify this marking scheme.
 var serverSaltLabel = []byte("outline-server-salt")
@@ -79,9 +79,9 @@ func NewServerSaltGenerator(secret string) ServerSaltGenerator {
 }
 
 func (sg serverSaltGenerator) splitSalt(salt []byte) (prefix, mark []byte, err error) {
-	prefixLen := len(salt) - ServerSaltMarkLen
+	prefixLen := len(salt) - serverSaltMarkLen
 	if prefixLen < 0 {
-		return nil, nil, fmt.Errorf("Salt is too short: %d < %d", len(salt), ServerSaltMarkLen)
+		return nil, nil, fmt.Errorf("Salt is too short: %d < %d", len(salt), serverSaltMarkLen)
 	}
 	return salt[:prefixLen], salt[prefixLen:], nil
 }
@@ -116,5 +116,5 @@ func (sg serverSaltGenerator) IsServerSalt(salt []byte) bool {
 		return false
 	}
 	tag := sg.getTag(prefix)
-	return bytes.Equal(tag[:ServerSaltMarkLen], mark)
+	return bytes.Equal(tag[:serverSaltMarkLen], mark)
 }

shadowsocks/stream.go

@@ -22,7 +22,7 @@ import (
 	"io"
 	"sync"
 
-	"github.com/Jigsaw-Code/outline-ss-server/slicepool"
+	"github.com/Jigsaw-Code/outline-ss-server/internal/slicepool"
 )
 
 // payloadSizeMask is the maximum size of payload in bytes.