v2 init commit

src/mod/ipscan/ipscan.go

@@ -0,0 +1,149 @@
+package ipscan
+
+import (
+	"bytes"
+	"fmt"
+	"net"
+	"sort"
+	"strconv"
+	"sync"
+	"time"
+
+	"github.com/go-ping/ping"
+)
+
+/*
+	IP Scanner
+
+	This module scan the given network range and return a list
+	of nearby nodes.
+*/
+
+type DiscoveredHost struct {
+	IP                string
+	Ping              int
+	Hostname          string
+	HttpPortDetected  bool
+	HttpsPortDetected bool
+}
+
+//Scan an IP range given the start and ending ip address
+func ScanIpRange(start, end string) ([]*DiscoveredHost, error) {
+	ipStart := net.ParseIP(start)
+	ipEnd := net.ParseIP(end)
+	if ipStart == nil || ipEnd == nil {
+		return nil, fmt.Errorf("Invalid IP address")
+	}
+
+	if bytes.Compare(ipStart, ipEnd) > 0 {
+		return nil, fmt.Errorf("Invalid IP range")
+	}
+
+	var wg sync.WaitGroup
+	hosts := make([]*DiscoveredHost, 0)
+	for ip := ipStart; bytes.Compare(ip, ipEnd) <= 0; inc(ip) {
+		wg.Add(1)
+		thisIp := ip.String()
+		go func(thisIp string) {
+			defer wg.Done()
+			host := &DiscoveredHost{IP: thisIp}
+			if err := host.CheckPing(); err != nil {
+				// skip if the host is unreachable
+				host.Ping = -1
+				hosts = append(hosts, host)
+				return
+			}
+
+			host.CheckHostname()
+			host.CheckPort("http", 80, &host.HttpPortDetected)
+			host.CheckPort("https", 443, &host.HttpsPortDetected)
+			fmt.Println("OK", host)
+			hosts = append(hosts, host)
+
+		}(thisIp)
+	}
+
+	//Wait until all go routine done
+	wg.Wait()
+	sortByIP(hosts)
+	return hosts, nil
+}
+
+func ScanCIDRRange(cidr string) ([]*DiscoveredHost, error) {
+	_, ipNet, err := net.ParseCIDR(cidr)
+	if err != nil {
+		return nil, err
+	}
+
+	ip := ipNet.IP.To4()
+	startIP := net.IPv4(ip[0], ip[1], ip[2], 1).String()
+	endIP := net.IPv4(ip[0], ip[1], ip[2], 254).String()
+
+	return ScanIpRange(startIP, endIP)
+}
+
+func inc(ip net.IP) {
+	for j := len(ip) - 1; j >= 0; j-- {
+		ip[j]++
+		if ip[j] > 0 {
+			break
+		}
+	}
+}
+
+func sortByIP(discovered []*DiscoveredHost) {
+	sort.Slice(discovered, func(i, j int) bool {
+		return discovered[i].IP < discovered[j].IP
+	})
+}
+
+func (host *DiscoveredHost) CheckPing() error {
+	// ping the host and set the ping time in milliseconds
+	pinger, err := ping.NewPinger(host.IP)
+	if err != nil {
+		return err
+	}
+	pinger.Count = 4
+	pinger.Timeout = time.Second
+	pinger.SetPrivileged(true) // This line may help on some systems
+	pinger.Run()
+	stats := pinger.Statistics()
+	if stats.PacketsRecv == 0 {
+		return fmt.Errorf("Host unreachable for " + host.IP)
+	}
+	host.Ping = int(stats.AvgRtt.Milliseconds())
+	return nil
+}
+
+func (host *DiscoveredHost) CheckHostname() {
+	// lookup the hostname for the IP address
+	names, err := net.LookupAddr(host.IP)
+	fmt.Println(names, err)
+	if err == nil && len(names) > 0 {
+		host.Hostname = names[0]
+	}
+}
+
+func (host *DiscoveredHost) CheckPort(protocol string, port int, detected *bool) {
+	// try to connect to the specified port on the host
+	conn, err := net.DialTimeout("tcp", net.JoinHostPort(host.IP, strconv.Itoa(port)), 1*time.Second)
+	if err == nil {
+		conn.Close()
+		*detected = true
+	}
+}
+
+func (host *DiscoveredHost) ScanPorts(startPort, endPort int) []int {
+	var openPorts []int
+
+	for port := startPort; port <= endPort; port++ {
+		target := fmt.Sprintf("%s:%d", host.IP, port)
+		conn, err := net.DialTimeout("tcp", target, time.Millisecond*500)
+		if err == nil {
+			conn.Close()
+			openPorts = append(openPorts, port)
+		}
+	}
+
+	return openPorts
+}