[优化] 使用 interactsh 反连随机选择可用的服务器

CHANGELOG.MD

@@ -3,6 +3,7 @@
 更新日志：
 
 - [BUG] 修复某些情况 `path` 开头包含多个 `/` 问题
+- [优化] 使用 `interactsh` 反连随机选择可用的服务器
 - [优化] 开启 `debug` 时请求响应限制打印长度
 
 感谢以下用户的贡献:

reverse/interact.go

@@ -22,12 +22,15 @@ import (
 	"crypto/rand"
 	"crypto/rsa"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/4ra1n/poc-runner/client"
 	"github.com/4ra1n/poc-runner/log"
+	"github.com/4ra1n/poc-runner/util"
 	"github.com/4ra1n/poc-runner/xerr"
 )
 
@@ -75,7 +78,55 @@ type Interact struct {
 
 func NewInteract(c *client.HttpClient, server string) (*Interact, error) {
 	if server == "" {
-		server = randomPick(defaultServers)
+		// 随机选取一个 default server
+		picker := util.NewPicker(defaultServers)
+
+		var (
+			ok       bool
+			tryTimes int
+		)
+
+		for {
+			tryTimes++
+
+			if tryTimes > 5 {
+				return nil, xerr.Wrap(errors.New("cannot connect to interact.sh server"))
+			}
+
+			server, ok = picker.RandomPick()
+			if !ok {
+				// 只有所有的 server 被选完没得选才会返回 false
+				return nil, xerr.Wrap(errors.New("all default server is invalid"))
+			}
+
+			var (
+				httpErr  error
+				httpsErr error
+			)
+
+			// 并发测试 http/https 只要有一个可用即可
+			wg := new(sync.WaitGroup)
+
+			wg.Add(2)
+
+			go func() {
+				defer wg.Done()
+				_, httpErr = c.Get("http://" + server)
+			}()
+
+			go func() {
+				defer wg.Done()
+				_, httpsErr = c.Get("https://" + server)
+			}()
+
+			wg.Wait()
+
+			// 任何一个不报错就使用它
+			if httpErr == nil || httpsErr == nil {
+				log.Infof("use reverse server: %s", server)
+				break
+			}
+		}
 	}
 	correlationID := randLower(20)
 	secretKey := randomUUID()

reverse/util.go

@@ -49,11 +49,6 @@ func randomUUID() string {
 	return fmt.Sprintf("%08x-%04x-%04x-%04x-%012x", uuid[0:4], uuid[4:6], uuid[6:8], uuid[8:10], uuid[10:])
 }
 
-func randomPick(choices []string) string {
-	randomIndex := rand.Intn(len(choices))
-	return choices[randomIndex]
-}
-
 func randUpper(n int) string {
 	letterRunes := []rune("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
 	b := make([]rune, n)

util/picker.go

@@ -0,0 +1,55 @@
+/*
+ * poc-runner project
+ * Copyright (C) 2024 4ra1n
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package util
+
+import (
+	"math/rand"
+	"time"
+)
+
+func init() {
+	rand.New(rand.NewSource(time.Now().UnixNano()))
+}
+
+type Picker struct {
+	choices []string
+	used    map[int]bool
+}
+
+func NewPicker(choices []string) *Picker {
+	return &Picker{
+		choices: choices,
+		used:    make(map[int]bool),
+	}
+}
+
+func (p *Picker) RandomPick() (string, bool) {
+	if len(p.used) == len(p.choices) {
+		return "", false
+	}
+	var index int
+	for {
+		index = rand.Intn(len(p.choices))
+		if !p.used[index] {
+			break
+		}
+	}
+	p.used[index] = true
+	return p.choices[index], true
+}