mcstatus/main.go
Michael 20edf2a7d5 first commit
Signed-off-by: Michael <michael.lindman@gmail.com>
2020-09-01 22:46:44 +01:00

136 lines
2.9 KiB
Go

package main
import (
"bytes"
"encoding/binary"
"encoding/json"
"flag"
"fmt"
"log"
"net"
"strconv"
"time"
)
func packetlength(b ...[]byte) (length int) {
for _, bytes := range b {
length += len(bytes)
}
return length
}
func handshake(addr string, port int, ver uint64) []byte {
id := []byte{0x00}
state := []byte{0x01}
version := make([]byte, 2)
binary.PutUvarint(version, ver)
p := make([]byte, 2)
binary.BigEndian.PutUint16(p, uint16(port))
length := packetlength(id, version, []byte(addr), []byte(p), state) + 1
var handshake bytes.Buffer
handshake.WriteByte(byte(length))
handshake.Write(id)
handshake.Write(version)
handshake.WriteByte(byte(len(addr)))
handshake.WriteString(addr)
handshake.Write(p)
handshake.Write(state)
return handshake.Bytes()
}
func main() {
addr := flag.String("addr", "127.0.0.1", "Server address")
port := flag.Int("port", 25565, "Server Port")
ver := flag.Uint64("ver", 751, "Minecraft protocol version number")
flag.Parse()
conn, err := net.Dial("tcp", *addr+":"+strconv.Itoa(*port))
if err != nil {
log.Fatal(err)
}
for {
err := conn.SetWriteDeadline(time.Now().Add(30 * time.Second))
if err != nil {
log.Println("WriteDealine failed:", err)
return
}
conn.Write(handshake(*addr, *port, *ver))
conn.Write([]byte{0x01, 0x00})
recvBuf := make([]byte, 512)
var resp response
err = conn.SetReadDeadline(time.Now().Add(10 * time.Second))
if err != nil {
log.Println("SetReadDealine failed:", err)
return
}
n, err := conn.Read(recvBuf)
if err != nil {
if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
log.Println("read timeout:", err)
} else {
log.Println("read error", err)
}
}
requestright := recvBuf[:n]
b := bytes.Split(requestright, []byte("{"))
ne := bytes.SplitAfterN(requestright, b[0], 2)
after := bytes.TrimSuffix(ne[1], []byte("\x00"))
if err := json.Unmarshal(after, &resp); err != nil {
log.Println(err)
conn.Close()
return
}
fmt.Printf("Name: %s\nPlayers: %d/%d\nVersion: %s\n",
resp.Description.Text,
resp.Players.Online,
resp.Players.Max,
resp.Version.Name)
if resp.Players.Online >= 1 {
fmt.Println("Online:")
for _, player := range resp.Players.Sample {
fmt.Printf("\t%s\n", player.Name)
}
}
recvBuf = make([]byte, 1)
start := time.Now()
conn.Write([]byte{0x01, 0x00})
_, _ = conn.Read(recvBuf[:])
diff := time.Now().Sub(start)
fmt.Printf("Ping: %+v\n", diff)
if err = conn.Close(); err != nil {
log.Println(err)
return
}
return
}
}
type response struct {
Version struct {
Name string `json:"name"`
Protocol int `json:"protocol"`
} `json:"version"`
Players struct {
Max int `json:"max"`
Online int `json:"online"`
Sample []struct {
Name string `json:"name"`
ID string `json:"id"`
} `json:"sample"`
} `json:"players"`
Description struct {
Text string `json:"text"`
} `json:"description"`
Favicon string `json:"favicon"`
}