tools.go_stun

Yohn Y. 2020-04-06 Parent:4b125c1ef311 Child:102fbdab34d8

tools.go_stun/main.go

+ Добавил разрешение имён. Просто так

awgur@0	1 package main
awgur@0	2
awgur@0	3 import (
awgur@0	4 "errors"
awgur@0	5 "fmt"
awgur@0	6 "log/syslog"
awgur@0	7 "net"
awgur@0	8 "os"
awgur@0	9 "strings"
awgur@0	10 "time"
awgur@0	11 )
awgur@0	12
awgur@0	13 const (
awgur@1	14 LOG_IDENT string = "net-a0fs-gostun"
awgur@0	15 )
awgur@0	16
awgur@0	17 func getPort() (res string, err error) {
awgur@0	18 if len(os.Args) < 2 {
awgur@0	19 err = errors.New("No port specify")
awgur@0	20 } else {
awgur@0	21 res = fmt.Sprintf(":%s", os.Args[1])
awgur@0	22 }
awgur@0	23 return
awgur@0	24 }
awgur@0	25
awgur@0	26 func fail(code int, msg string) {
awgur@0	27 usage := "Usage: cmd port"
awgur@0	28 usage += "\n port: port number for listening clients"
awgur@0	29
awgur@0	30 fmt.Fprintln(os.Stderr, msg)
awgur@0	31 fmt.Fprintln(os.Stderr, usage)
awgur@0	32 os.Exit(code)
awgur@0	33 return
awgur@0	34 }
awgur@0	35
awgur@0	36 func handler(conn net.Conn) {
awgur@0	37 log, err := syslog.New(syslog.LOG_USER, LOG_IDENT)
awgur@0	38 if err != nil {
awgur@0	39 panic(err)
awgur@0	40 }
awgur@0	41
awgur@0	42 _s_tm := time.Now()
awgur@0	43 remoteAddr := conn.RemoteAddr().String()
awgur@0	44
awgur@0	45 defer func() {
awgur@0	46 var err error
awgur@0	47 _s_tmd := time.Now().Sub(_s_tm)
awgur@0	48 if r_err := recover(); r_err != nil {
awgur@0	49 err = log.Err(fmt.Sprintf("Error on service for %s (service time: %v): %v", remoteAddr, _s_tmd, r_err))
awgur@0	50 if err != nil {
awgur@1	51 panic(err.Error())
awgur@0	52 }
awgur@0	53 } else {
awgur@0	54 err = conn.Close()
awgur@0	55 if err != nil {
awgur@0	56 err = log.Err(fmt.Sprintf("Error on closing socket when service %s (service time: %v): %v",
awgur@0	57 remoteAddr, _s_tmd, err))
awgur@0	58
awgur@0	59 if err != nil {
awgur@1	60 panic(err.Error())
awgur@0	61 }
awgur@0	62 } else {
awgur@1	63 _ = log.Info(fmt.Sprintf("Ok service %s in %v", remoteAddr, _s_tmd))
awgur@0	64 }
awgur@0	65 }
awgur@0	66 }()
awgur@0	67
awgur@0	68 addr_spit := strings.Split(remoteAddr, ":")
awgur@0	69 addr_last := len(addr_spit) - 1
awgur@2	70 addr := strings.Join(addr_spit[:addr_last], ":")
awgur@2	71
awgur@2	72 var dns string
awgur@2	73 dns_names, err := net.LookupAddr(strings.Trim(addr, "[] "))
awgur@2	74 if err != nil {
awgur@2	75 log.Warning(fmt.Sprintf("Fail to resolve dns name for %s: %v", remoteAddr, err))
awgur@2	76 } else {
awgur@2	77 for _, dns_name := range dns_names {
awgur@2	78 dns += "Name: " + dns_name + "\n"
awgur@2	79 }
awgur@2	80 }
awgur@2	81 addr = "IP: " + addr + "\n"
awgur@0	82 port := "Port: " + addr_spit[addr_last] + "\n"
awgur@0	83
awgur@0	84 if _, err := conn.Write([]byte(addr)); err != nil {
awgur@1	85 panic(err.Error())
awgur@0	86 }
awgur@2	87 if _, err := conn.Write([]byte(dns)); err != nil {
awgur@2	88 panic(err.Error())
awgur@2	89 }
awgur@0	90 if _, err := conn.Write([]byte(port)); err != nil {
awgur@1	91 panic(err.Error())
awgur@0	92 }
awgur@0	93 }
awgur@0	94
awgur@0	95 func main() {
awgur@0	96 port, err := getPort()
awgur@0	97 if err != nil {
awgur@0	98 fail(1, fmt.Sprint("Error in parsing port number: ", err))
awgur@0	99 }
awgur@0	100
awgur@0	101 svc, err := net.Listen("tcp", port)
awgur@0	102 if err != nil {
awgur@0	103 fail(2, fmt.Sprint("Fail to open socket: ", err))
awgur@0	104 }
awgur@0	105
awgur@0	106 for {
awgur@0	107 conn, err := svc.Accept()
awgur@0	108 if err != nil {
awgur@0	109 fail(1, fmt.Sprint("Error accepting connections: ", err))
awgur@0	110 }
awgur@0	111 go handler(conn)
awgur@0	112 }
awgur@0	113 }