109 lines
2.0 KiB
Go
109 lines
2.0 KiB
Go
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package main
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import (
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"net"
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"os"
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"fmt"
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"bufio"
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"strings"
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"strconv"
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)
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func largestOrder(msg string) string {
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orders := strings.Split(msg, ",")
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largest := 0
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result := ""
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for i := range orders {
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l := orders[i]
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parts := strings.Split(l, "x")
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amount, err := strconv.Atoi(parts[0])
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if err == nil && amount > largest {
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largest = amount
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result = l
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}
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}
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return result
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}
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type SecureServer struct {
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port uint16
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}
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func NewSecureServer(port uint16) *SecureServer {
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return &SecureServer{
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port,
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}
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}
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type SecureSession struct{
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con net.Conn
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}
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func NewSecureSession(con net.Conn) *SecureSession {
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return &SecureSession{
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con,
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}
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}
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func (s *SecureServer) Run() {
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addr := fmt.Sprintf("0.0.0.0:%d", s.port)
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server, err := net.Listen("tcp", addr)
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if err != nil {
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fmt.Println("Error listening:", err.Error())
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os.Exit(1)
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}
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defer server.Close()
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fmt.Println("SecureServer waiting for client...")
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for {
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connection, err := server.Accept()
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if err != nil {
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fmt.Println("Error accepting: ", err.Error())
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os.Exit(1)
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}
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fmt.Println("client connected")
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s.processClient(connection)
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}
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}
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func (s *SecureServer) processClient(con net.Conn) {
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session := NewSecureSession( con)
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go session.SecureReceiver()
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}
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func (s *SecureSession) setEncryption(r *bufio.Reader) error {
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secdef, err := r.ReadBytes('\x00')
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if err != nil { return err }
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fmt.Printf("secdef: %s\n", secdef)
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return nil
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}
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func (s *SecureSession) query(r *bufio.Reader) error {
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msg, err := r.ReadString('\n')
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if err != nil { return err }
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msg = strings.TrimSpace(msg)
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fmt.Printf("Q: %s", msg)
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a := largestOrder(msg)
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fmt.Printf("A: %s\n", a)
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s.con.Write(append([]byte(a), []byte("\n")...))
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return nil
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}
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func (s *SecureSession) close() {
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fmt.Printf("close\n")
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s.con.Close()
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}
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func (s *SecureSession) SecureReceiver() {
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defer s.close()
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r := bufio.NewReaderSize(s.con, 5000)
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err := s.setEncryption(r)
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for err == nil {
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err = s.query(r)
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}
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}
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