Merge pull request #24 from alfiankan/23-use-bash-c-maybe-leak-chaild…

…-process

23 use bash c maybe leak chaild process

empty/config.yaml

@@ -3,4 +3,5 @@ teleterm:
   shell_executor: "/bin/bash"
 whitelist:
   - <USER_ID>
-  - <USER_ID>
+  - <USER_ID>
+execution_timeout_second: 10

executor/command.go

@@ -1,29 +1,64 @@
 package executor
 
 import (
+	"errors"
 	"fmt"
 	"os/exec"
+	"time"
 
 	"github.com/spf13/viper"
 )
 
-type CommandOutputWriter struct{}
+type CommandOutputWriter struct {
+	TimeoutSecond int
+}
+
+type CmdExecutionResult struct {
+  Stdout []byte
+  Stderr []byte
+}
+
 
 func (c *CommandOutputWriter) ExecFullOutput(command string) (outOk []byte, outErr []byte, err error) {
 
-	executor := viper.GetString("shell_executor")
+  chResponse := make(chan CmdExecutionResult)
+
+  executor := viper.GetString("shell_executor")
 	if executor == "" {
 		executor = "/bin/bash"
 	}
 
 	cmd := exec.Command(executor, "-c", command)
 
-	out, err := cmd.CombinedOutput()
-	if err != nil {
-		outErr = out
-		return
+	go func(cnl chan CmdExecutionResult, cmd *exec.Cmd) {
+
+    out, err := cmd.CombinedOutput()
+    errOut := []byte("")
+    if err != nil {
+      errOut = []byte(err.Error())
+    }
+    cnl <- CmdExecutionResult{Stdout: out, Stderr: errOut}
+
+	}(chResponse, cmd)
+
+  if c.TimeoutSecond == 0 {
+    result := <-chResponse
+    outOk = result.Stdout
+    outErr = result.Stderr
+    return
+  }
+
+  select {
+    case result := <-chResponse:
+      outOk = result.Stdout
+      outErr = result.Stderr
+      cmd.Process.Kill()
+	  case <-time.After(time.Second * time.Duration(c.TimeoutSecond)):
+      cmd.Process.Kill()
+      errMsg := "TIMEOUT: EXCEEDED -- Process killed"
+		  err = errors.New(errMsg)
+      outErr = []byte(errMsg)
 	}
-	outOk = out
 
 	return
 }

teleterm/telegram_handler.go

@@ -50,9 +50,11 @@ func createButtonReplay(ctx context.Context, persist Persistence, menu *tele.Rep
 func Start(ctx context.Context, db *sql.DB, telebotToken string) {
 
 	log := common.InitLog()
-	log.Info().Str("version", "v2.0.0").Msg("Starting Teleterm")
+	log.Info().Str("version", "v2.2.0").Msg("Starting Teleterm")
 
-	commandExecutor := new(executor.CommandOutputWriter)
+  commandExecutor := executor.CommandOutputWriter{
+    TimeoutSecond: viper.GetInt("execution_timeout_second"),
+  }
 	persist := Persistence{db: db}
 
 	pref := tele.Settings{
@@ -67,12 +69,14 @@ func Start(ctx context.Context, db *sql.DB, telebotToken string) {
 	}
 
 	configWhitelist := viper.GetIntSlice("whitelist")
-	var whitelist []int64
-	for _, id := range configWhitelist {
-		whitelist = append(whitelist, int64(id))
-	}
-	b.Use(middleware.Whitelist(whitelist...))
-
+  log.Info().Str("state", "white listing").Msg(fmt.Sprintf("total: %v", len(configWhitelist)))
+  if len(configWhitelist) > 0 {
+	  var whitelist []int64
+	  for _, id := range configWhitelist {
+		  whitelist = append(whitelist, int64(id))
+	  }
+	  b.Use(middleware.Whitelist(whitelist...))
+  }
 	menu := &tele.ReplyMarkup{ResizeKeyboard: true}
 
 	b.Handle("/refresh", func(c tele.Context) error {