diff --git a/cmd/root.go b/cmd/root.go
index 342f7ca..ff285f8 100644
--- a/cmd/root.go
+++ b/cmd/root.go
@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"bufio"
 	"fmt"
 	"log"
 	"os"
@@ -14,13 +15,20 @@ var rootCmd = &cobra.Command{
 	Use:   "nali",
 	Short: "",
 	Long:  ``,
-	Args:  cobra.MinimumNArgs(1),
+	Args:  cobra.MinimumNArgs(0),
 	Run: func(cmd *cobra.Command, args []string) {
 		if len(args) == 0 {
-			fmt.Println("Usage: balabala")
-			return
+			stdin := bufio.NewScanner(os.Stdin)
+			for stdin.Scan() {
+				line := stdin.Text()
+				if line == "quit" || line == "exit" {
+					return
+				}
+				fmt.Println(app.ReplaceInString(line))
+			}
+		} else {
+			app.ParseIPs(args)
 		}
-		app.ParseIPs(args)
 	},
 }
 
diff --git a/go.sum b/go.sum
index 3012cc5..ae053a3 100644
--- a/go.sum
+++ b/go.sum
@@ -32,6 +32,7 @@ github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfU
 github.com/golang/groupcache v0.0.0-20190129154638-5b532d6fd5ef/go.mod h1:cIg4eruTrX1D+g88fzRXU5OdNfaM+9IcxsU14FzY7Hc=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
 github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.1 h1:YF8+flBXS5eO826T4nzqPrxfhQThhXl0YzfuUPu4SBg=
 github.com/golang/protobuf v1.3.1/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
 github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/go-cmp v0.2.0/go.mod h1:oXzfMopK8JAjlY9xF4vHSVASa0yLyX7SntLO5aqRK0M=
@@ -146,6 +147,7 @@ golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGm
 golang.org/x/tools v0.0.0-20190114222345-bf090417da8b/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20190311212946-11955173bddd/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 google.golang.org/appengine v1.1.0/go.mod h1:EbEs0AVv82hx2wNQdGPgUI5lhzA/G0D9YwlJXL52JkM=
+google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8 h1:Nw54tB0rB7hY/N0NQvRW8DG4Yk3Q6T9cu9RcFQDu1tc=
 google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8/go.mod h1:JiN7NxoALGmiZfu7CAH4rXhgtRTLTxftemlI0sWmxmc=
 google.golang.org/grpc v1.19.0/go.mod h1:mqu4LbDTu4XGKhr4mRzUsmM4RtVoemTSY81AxZiDr8c=
 google.golang.org/grpc v1.21.0/go.mod h1:oYelfM1adQP15Ek0mdvEgi9Df8B9CZIaU1084ijfRaM=
diff --git a/internal/app/parse.go b/internal/app/parse.go
index bd12e4b..54606aa 100644
--- a/internal/app/parse.go
+++ b/internal/app/parse.go
@@ -3,6 +3,9 @@ package app
 import (
 	"fmt"
 	"path/filepath"
+	"strings"
+
+	"github.com/zu1k/nali/internal/iptools"
 
 	"github.com/zu1k/nali/constant"
 
@@ -39,14 +42,23 @@ func SetDB(dbName ipdb.IPDBType) {
 // parse several ips
 func ParseIPs(ips []string) {
 	for _, ip := range ips {
-		ParseIP(ip)
+		if iptools.ValidIP4(ip) {
+			result := db.Find(ip)
+			fmt.Println(formatResult(ip, result))
+		} else {
+			fmt.Println(ReplaceInString(ip))
+		}
 	}
 }
 
-// parse one ip
-func ParseIP(ip string) {
-	result := db.Find(ip)
-	fmt.Println(formatResult(ip, result))
+func ReplaceInString(str string) (result string) {
+	result = str
+	ips := iptools.GetIP4FromString(str)
+	for _, ip := range ips {
+		info := db.Find(ip)
+		result = strings.ReplaceAll(result, ip, formatResult(ip, info))
+	}
+	return
 }
 
 func formatResult(ip string, result string) string {
diff --git a/internal/iptools/ipparser.go b/internal/iptools/ipparser.go
new file mode 100644
index 0000000..a362cd4
--- /dev/null
+++ b/internal/iptools/ipparser.go
@@ -0,0 +1,26 @@
+package iptools
+
+import (
+	"regexp"
+	"strings"
+)
+
+var (
+	ipv4re0 *regexp.Regexp
+	ipv4re  *regexp.Regexp
+)
+
+func init() {
+	ipv4re0 = regexp.MustCompile(`^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}$`)
+	ipv4re = regexp.MustCompile(`(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}`)
+}
+
+func ValidIP4(str string) bool {
+	str = strings.Trim(str, " ")
+	return ipv4re0.MatchString(str)
+}
+
+func GetIP4FromString(str string) []string {
+	str = strings.Trim(str, " ")
+	return ipv4re.FindAllString(str, -1)
+}
diff --git a/internal/iptools/iptools_test.go b/internal/iptools/iptools_test.go
new file mode 100644
index 0000000..9cd3fa3
--- /dev/null
+++ b/internal/iptools/iptools_test.go
@@ -0,0 +1,12 @@
+package iptools
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestIP4Re(t *testing.T) {
+	str := "aaa1.1.11.23a36.36.32.200"
+	fmt.Println(GetIP4FromString(str))
+	fmt.Println(ValidIP4(str))
+}