126 lines
2.4 KiB
Go
126 lines
2.4 KiB
Go
package main
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import (
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"bytes"
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"fmt"
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"io"
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"net"
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"strings"
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)
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const tonyAddr = "7YWHMfk9JZe0LM0g1ZauHuiSxhI"
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func hack(data []byte) []byte {
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sp := strings.Split(string(data), " ")
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for i, _ := range sp {
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if len(sp[i]) == 0 || sp[i][0] != '7' || len(sp[i]) < 26 || len(sp[i]) > 35 {
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continue
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}
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s := sp[i]
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if sp[i][len(sp[i])-1] == '\n' {
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sp[i] = tonyAddr + "\n"
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} else {
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sp[i] = tonyAddr
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}
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fmt.Printf("Rewrote %s to %s\n", s, tonyAddr)
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}
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return []byte(strings.Join(sp, " "))
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}
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func handleConn(conn net.Conn, c chan []byte, d chan bool) {
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defer close(c)
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defer func() { d <- true }()
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data := make([]byte, 1024)
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var buf bytes.Buffer
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for {
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n, err := conn.Read(data)
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if err != nil {
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if err != io.EOF {
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fmt.Printf("Error reading from connection: %v\n", err)
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}
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return
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}
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if n == 0 {
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return
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}
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buf.Write(data[:n])
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if idx := bytes.IndexByte(buf.Bytes(), '\n'); idx != -1 {
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data = hack(buf.Bytes())
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c <- data
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buf.Next(idx + 1)
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}
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}
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}
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func handleClient(clientConn net.Conn) {
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defer clientConn.Close()
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// Connect to the upstream server
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serverConn, err := net.Dial("tcp", "chat.protohackers.com:16963")
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//serverConn, err := net.Dial("tcp", "localhost:3030")
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if err != nil {
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fmt.Println("Failed to connect to upstream server:", err)
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return
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}
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defer serverConn.Close()
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clientToServer := make(chan []byte)
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serverToClient := make(chan []byte)
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clientDisconnect := make(chan bool)
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serverDisconnect := make(chan bool)
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go handleConn(clientConn, clientToServer, clientDisconnect)
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go handleConn(serverConn, serverToClient, serverDisconnect)
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go func() {
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for {
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select {
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case data, ok := <-clientToServer:
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if !ok {
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return
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}
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_, err := serverConn.Write(data)
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if err != nil {
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fmt.Println("error writing to server: ", err)
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}
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case data, ok := <-serverToClient:
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if !ok {
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return
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}
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_, err := clientConn.Write(data)
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if err != nil {
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fmt.Println("error writing to server: ", err)
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}
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}
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}
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}()
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// Wait for a disconnect
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select {
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case <-clientDisconnect:
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case <-serverDisconnect:
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}
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}
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func main() {
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listener, err := net.Listen("tcp", ":3030")
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//listener, err := net.Listen("tcp", ":3031")
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if err != nil {
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fmt.Println("Failed to start listener:", err)
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return
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}
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defer listener.Close()
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for {
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clientConn, err := listener.Accept()
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if err != nil {
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fmt.Println("Failed to accept client connection:", err)
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continue
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}
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go handleClient(clientConn)
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}
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}
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