closes #31

internal/result/print.go

@@ -21,6 +21,9 @@ func (r *Result) Print() {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		r.hostPrinter(hh)
 		r.portPrinter(hh)
 	}
@@ -33,6 +36,9 @@ func (r *Result) PrintHost(h *Host) {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		if hh.IP.Equal(h.IP) {
 			r.hostPrinter(hh)
 		} else if hh.Name != "" && hh.Name == h.Name {
@@ -89,6 +95,9 @@ func (r *Result) PrintAlive() {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		if r.allPortsClosed(hh) {
 			r.Logger.Debugf("all ports closed: %v", hh.IP)
 			continue
@@ -111,6 +120,9 @@ func (r *Result) PrintByService(service string) {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		if r.allPortsClosed(hh) {
 			continue
 		}
@@ -142,6 +154,9 @@ func (r *Result) PrintServices() {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		for k, v := range hh.TCPPorts {
 			r.Logger.Debugf("matched: %v", hh.GetName())
 			s := r.formatService(hh.GetName(), k, v.Name)
@@ -169,6 +184,9 @@ func (r *Result) PrintByPort(port []int) {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		if r.allPortsClosed(hh) {
 			continue
 		}
@@ -192,6 +210,9 @@ func (r *Result) PrintPortSummary() {
 		if hh.IsExcluded(r.Exclude) {
 			continue
 		}
+		if hh.NotInCIDR(r.CIDR) {
+			continue
+		}
 		for k := range hh.TCPPorts {
 			p[k] = struct{}{}
 		}

internal/result/result.go

@@ -12,6 +12,7 @@ type Result struct {
 	Logger  *cli.Logger
 	Hosts   []*Host
 	Exclude []string
+	CIDR    *net.IPNet
 }
 
 func (r *Result) SortByIP() {
@@ -21,11 +22,24 @@ func (r *Result) SortByIP() {
 
 }
 
-func New(logger *cli.Logger, exclude []string) *Result {
+func New(logger *cli.Logger, exclude []string, cidr string) *Result {
+	c, err := parseCIDR(cidr)
+	if err != nil {
+		logger.Errorf("error parsing CIDR: %s", err)
+	}
 	return &Result{
 		Logger:  logger,
 		Exclude: exclude,
+		CIDR:    c,
+	}
+}
+
+func parseCIDR(cidr string) (*net.IPNet, error) {
+	_, c, err := net.ParseCIDR(cidr)
+	if err != nil {
+		return nil, err
 	}
+	return c, nil
 }
 
 func (r *Result) AddHost(newHost *Host) {
@@ -65,6 +79,10 @@ func (h *Host) IsExcluded(el []string) bool {
 	return false
 }
 
+func (h *Host) NotInCIDR(c *net.IPNet) bool {
+	return !c.Contains(h.IP)
+}
+
 func (h *Host) updateName(hostname string) {
 	// Don't overwrite
 	if h.Name == "" && hostname != "" {

internal/runner/options.go

@@ -4,13 +4,17 @@ import (
 	"flag"
 	"strconv"
 	"strings"
+
+	"github.com/Masterminds/log-go"
+	"github.com/Masterminds/log-go/impl/cli"
 )
 
 type Options struct {
 	Exclude  []string
 	JSON     bool
 	Host     string
 	Hosts    bool
+	CIDR     string
 	Path     string
 	Port     []int
 	Ports    bool
@@ -21,10 +25,13 @@ type Options struct {
 
 func ParseOptions() *Options {
 	options := &Options{}
+	logger := cli.NewStandard()
+	logger.Level = log.ErrorLevel
 	exclude := flag.String("exclude", "", "Exclude these hosts from output")
 	flag.BoolVar(&options.JSON, "json", false, "Display JSON output")
 	flag.StringVar(&options.Host, "host", "", "Show results for specified host")
 	flag.BoolVar(&options.Hosts, "hosts", false, "Print alive hosts")
+	flag.StringVar(&options.CIDR, "cidr", "0.0.0.0/0", "CIDR range to output")
 	flag.StringVar(&options.Path, "path", ".", "Path to scan file")
 	port := flag.String("port", "", "Display hosts with matching port(s)")
 	flag.BoolVar(&options.Ports, "ports", false, "Print all ports")

internal/runner/runner.go

@@ -34,7 +34,7 @@ func New(options *Options) *Runner {
 
 func (r *Runner) Run() {
 	r.GetScanFiles()
-	res := result.New(r.Logger, r.Options.Exclude)
+	res := result.New(r.Logger, r.Options.Exclude, r.Options.CIDR)
 	for _, ff := range r.Files {
 		r.Logger.Debugf("processing %v", ff)
 		// Get last modified time for timeline output