96 lines
1.9 KiB
Go
Executable File
96 lines
1.9 KiB
Go
Executable File
package main
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import (
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"fmt"
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"net"
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"encoding/binary"
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"errors"
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"time"
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)
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func main() {
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l, err := net.Listen("tcp", "0.0.0.0:48101")
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if err != nil {
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fmt.Println(err)
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return
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}
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for {
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conn, err := l.Accept()
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if err != nil {
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break
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}
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go handleConnection(conn)
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}
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}
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func handleConnection(conn net.Conn) {
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defer conn.Close()
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conn.SetDeadline(time.Now().Add(10 * time.Second))
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bufChk, err := readXBytes(conn, 1)
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if err != nil {
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return
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}
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var ipInt uint32
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var portInt uint16
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if bufChk[0] == 0 {
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ipBuf, err := readXBytes(conn, 4)
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if err != nil {
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return
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}
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ipInt = binary.BigEndian.Uint32(ipBuf)
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portBuf, err := readXBytes(conn, 2)
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if err != nil {
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return;
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}
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portInt = binary.BigEndian.Uint16(portBuf)
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} else {
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ipBuf, err := readXBytes(conn, 3)
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if err != nil {
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return;
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}
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ipBuf = append(bufChk, ipBuf...)
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ipInt = binary.BigEndian.Uint32(ipBuf)
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portInt = 23
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}
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uLenBuf, err := readXBytes(conn, 1)
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if err != nil {
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return
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}
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usernameBuf, err := readXBytes(conn, int(byte(uLenBuf[0])))
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pLenBuf, err := readXBytes(conn, 1)
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if err != nil {
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return
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}
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passwordBuf, err := readXBytes(conn, int(byte(pLenBuf[0])))
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if err != nil {
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return
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}
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fmt.Printf("%d.%d.%d.%d:%d %s:%s\n", (ipInt >> 24) & 0xff, (ipInt >> 16) & 0xff, (ipInt >> 8) & 0xff, ipInt & 0xff, portInt, string(usernameBuf), string(passwordBuf))
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}
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func readXBytes(conn net.Conn, amount int) ([]byte, error) {
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buf := make([]byte, amount)
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tl := 0
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for tl < amount {
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rd, err := conn.Read(buf[tl:])
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if err != nil || rd <= 0 {
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return nil, errors.New("Failed to read")
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}
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tl += rd
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}
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return buf, nil
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}
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