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利用golang的并发优势快速扫描端口
Scanner startIp [endIp] port thread
package main import ( "flag" "fmt" "net" "os" "strconv" "strings" ) /** 扫描地址 */ var ipAddrs chan string = make(chan string) //扫描结果 var result chan string = make(chan string) //线程数 var thread chan int = make(chan int) var nowThread int //关闭程序 var clo chan bool = make(chan bool) //保存结果 func writeResult() { fileName := "result.txt" fout, err := os.Create(fileName) if err != nil { //文件创建失败 fmt.Println(fileName + " create error") } defer fout.Close() s, ok := <-result for ok { fout.WriteString(s + "\r\n") s, ok = <-result } //通知进程退出 clo <- true } //根据线程参数启动扫描线程 func runScan() { t, ok := <-thread nowThread = t if ok { for i := 0; i < nowThread; i++ { go scan(strconv.Itoa(i)) } } //等待线程终止 for <-thread == 0 { nowThread-- if nowThread == 0 { //全部线程已终止,关闭结果写入,退出程序 close(result) break } } } /** 扫描线程 */ func scan(threadId string) { s, ok := <-ipAddrs //循环从通道中拿地址 for ok { fmt.Println("[thread-" + threadId + "] scan:" + s) _, err := net.Dial("tcp", s) if err == nil { //端口开放 result <- s } s, ok = <-ipAddrs //循环从通道中拿地址 } fmt.Println("[thread-" + threadId + "] end") thread <- 0 } //获取下一个IP func nextIp(ip string) string { ips := strings.Split(ip, ".") var i int for i = len(ips) - 1; i >= 0; i-- { n, _ := strconv.Atoi(ips[i]) if n >= 255 { //进位 ips[i] = "1" } else { //+1 n++ ips[i] = strconv.Itoa(n) break } } if i == -1 { //全部IP段都进行了进位,说明此IP本身已超出范围 return "" } ip = "" leng := len(ips) for i := 0; i < leng; i++ { if i == leng-1 { ip += ips[i] } else { ip += ips[i] + "." } } return ip } //生成IP地址列表 func processIp(startIp, endIp string) []string { var ips = make([]string, 0) for ; startIp != endIp; startIp = nextIp(startIp) { if startIp != "" { ips = append(ips, startIp) } } ips = append(ips, startIp) return ips } //处理参数 func processFlag(arg []string) { //开始IP,结束IP var startIp, endIp string //端口 var ports []int = make([]int, 0) index := 0 startIp = arg[index] si := net.ParseIP(startIp) if si == nil { //开始IP不合法 fmt.Println("'startIp' Setting error") return } index++ endIp = arg[index] ei := net.ParseIP(endIp) if ei == nil { //未指定结束IP,即只扫描一个IP endIp = startIp } else { index++ } tmpPort := arg[index] if strings.Index(tmpPort, "-") != -1 { //连续端口 tmpPorts := strings.Split(tmpPort, "-") var startPort, endPort int var err error startPort, err = strconv.Atoi(tmpPorts[0]) if err != nil || startPort < 1 || startPort > 65535 { //开始端口不合法 return } if len(tmpPorts) >= 2 { //指定结束端口 endPort, err = strconv.Atoi(tmpPorts[1]) if err != nil || endPort < 1 || endPort > 65535 || endPort < startPort { //结束端口不合法 fmt.Println("'endPort' Setting error") return } } else { //未指定结束端口 endPort = 65535 } for i := 0; startPort+i <= endPort; i++ { ports = append(ports, startPort+i) } } else { //一个或多个端口 ps := strings.Split(tmpPort, ",") for i := 0; i < len(ps); i++ { p, err := strconv.Atoi(ps[i]) if err != nil { //端口不合法 fmt.Println("'port' Setting error") return } ports = append(ports, p) } } index++ t, err := strconv.Atoi(arg[index]) if err != nil { //线程不合法 fmt.Println("'thread' Setting error") return } //最大线程2048 if t < 1 { t = 1 } else if t > 2048 { t = 2048 } //传送启动线程数 thread <- t //生成扫描地址列表 ips := processIp(startIp, endIp) il := len(ips) for i := 0; i < il; i++ { pl := len(ports) for j := 0; j < pl; j++ { ipAddrs <- ips[i] + ":" + strconv.Itoa(ports[j]) } } close(ipAddrs) } func main() { flag.Parse() if flag.NArg() != 3 && flag.NArg() != 4 { //参数不合法 fmt.Println("Parameter error") return } //获取参数 args := make([]string, 0, 4) for i := 0; i < flag.NArg(); i++ { args = append(args, flag.Arg(i)) } //启动扫描线程 go runScan() //启动结果写入线程 go writeResult() //参数处理 processFlag(args) //等待退出指令 <-clo fmt.Println("Exit") } 转载地址：http://namhl.baihongyu.com/