From 097c2d22417d3a92a4eb7c0ea7273e8ca5a0e8ee Mon Sep 17 00:00:00 2001
From: zu1k <i@lgf.im>
Date: Thu, 20 Aug 2020 22:30:59 +0800
Subject: [PATCH] add trojan support

---
 pkg/getter/base.go  |   2 +
 pkg/proxy/trojan.go | 147 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 149 insertions(+)
 create mode 100644 pkg/proxy/trojan.go

diff --git a/pkg/getter/base.go b/pkg/getter/base.go
index eab4a094..7deaeb4c 100644
--- a/pkg/getter/base.go
+++ b/pkg/getter/base.go
@@ -39,6 +39,8 @@ func String2Proxy(link string) proxy.Proxy {
 		data, err = proxy.ParseVmessLink(link)
 	} else if strings.HasPrefix(link, "ss://") {
 		data, err = proxy.ParseSSLink(link)
+	} else if strings.HasPrefix(link, "trojan://") {
+		data, err = proxy.ParseTrojanLink(link)
 	}
 	if err != nil {
 		return nil
diff --git a/pkg/proxy/trojan.go b/pkg/proxy/trojan.go
new file mode 100644
index 00000000..adb279e2
--- /dev/null
+++ b/pkg/proxy/trojan.go
@@ -0,0 +1,147 @@
+package proxy
+
+import (
+	"encoding/json"
+	"errors"
+	"math/rand"
+	"net"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var (
+	ErrorNotTrojanink = errors.New("not a correct trojan link")
+)
+
+type Trojan struct {
+	Base
+	Password       string   `yaml:"password" json:"password"`
+	ALPN           []string `yaml:"alpn,omitempty" json:"alpn,omitempty"`
+	SNI            string   `yaml:"sni,omitempty" json:"sni,omitempty"`
+	SkipCertVerify bool     `yaml:"skip-cert-verify,omitempty" json:"skip-cert-verify,omitempty"`
+	UDP            bool     `yaml:"udp,omitempty" json:"udp,omitempty"`
+}
+
+/**
+  - name: "trojan"
+    type: trojan
+    server: server
+    port: 443
+    password: yourpsk
+    # udp: true
+    # sni: example.com # aka server name
+    # alpn:
+    #   - h2
+    #   - http/1.1
+    # skip-cert-verify: true
+*/
+
+func (t Trojan) Identifier() string {
+	return net.JoinHostPort(t.Server, strconv.Itoa(t.Port)) + t.Password
+}
+
+func (t Trojan) String() string {
+	data, err := json.Marshal(t)
+	if err != nil {
+		return ""
+	}
+	return string(data)
+}
+
+func (t Trojan) ToClash() string {
+	data, err := json.Marshal(t)
+	if err != nil {
+		return ""
+	}
+	return "- " + string(data)
+}
+
+func (t Trojan) ToSurge() string {
+	return ""
+}
+
+func (t Trojan) Clone() Proxy {
+	return &t
+}
+
+func ParseTrojanLink(link string) (*Trojan, error) {
+	if !strings.HasPrefix(link, "trojan://") || !strings.HasPrefix(link, "trojan-go://") {
+		return nil, ErrorNotSSRLink
+	}
+
+	/**
+	trojan-go://
+	    $(trojan-password)
+	    @
+	    trojan-host
+	    :
+	    port
+	/?
+	    sni=$(tls-sni.com)&
+	    type=$(original|ws|h2|h2+ws)&
+	        host=$(websocket-host.com)&
+	        path=$(/websocket/path)&
+	    encryption=$(ss;aes-256-gcm;ss-password)&
+	    plugin=$(...)
+	#$(descriptive-text)
+	*/
+
+	uri, err := url.Parse(link)
+	if err != nil {
+		return nil, ErrorNotSSLink
+	}
+
+	password := uri.User.Username()
+	password, _ = url.QueryUnescape(password)
+
+	server := uri.Hostname()
+	port, _ := strconv.Atoi(uri.Port())
+
+	moreInfos := uri.Query()
+	sni := moreInfos.Get("sni")
+	sni, _ = url.QueryUnescape(sni)
+	transformType := moreInfos.Get("type")
+	transformType, _ = url.QueryUnescape(transformType)
+	host := moreInfos.Get("host")
+	host, _ = url.QueryUnescape(host)
+	path := moreInfos.Get("path")
+	path, _ = url.QueryUnescape(path)
+
+	alpn := make([]string, 0)
+	if transformType == "h2" {
+		alpn = append(alpn, "h2")
+	}
+
+	if port == 0 {
+		return nil, ErrorNotTrojanink
+	}
+
+	return &Trojan{
+		Base: Base{
+			Name:   strconv.Itoa(rand.Int()),
+			Server: server,
+			Port:   port,
+			Type:   "trojan",
+		},
+		Password:       password,
+		ALPN:           alpn,
+		UDP:            true,
+		SNI:            host,
+		SkipCertVerify: true,
+	}, nil
+}
+
+var (
+	trojanPlainRe = regexp.MustCompile("trojan(-go)?://([A-Za-z0-9+/_&?=@:%.-])+")
+)
+
+func GrepTrojanLinkFromString(text string) []string {
+	results := make([]string, 0)
+	texts := strings.Split(text, "trojan://")
+	for _, text := range texts {
+		results = append(results, ssPlainRe.FindAllString("trojan://"+text, -1)...)
+	}
+	return results
+}