Add support for network interface selection #45

README.md

@@ -43,6 +43,7 @@ All funds that are donated to this project will be donated to charity. A full lo
 - automatically disable progress output when output is redirected
 - fix extra special characters when run with `--no-progress`
 - warn when using vhost mode with a proxy and http based urls as this might not work as expected
+- add `interface` and `local-ip` parameters to specify the interface for http requests
 
 ## 3.6
 

cli/options.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"crypto/tls"
 	"fmt"
+	"net"
 	"os"
 	"regexp"
 	"strconv"
@@ -31,6 +32,8 @@ func BasicHTTPOptions() []cli.Flag {
 		&cli.StringFlag{Name: "client-cert-pem-key", Aliases: []string{"ccpk"}, Usage: "private key in PEM format for optional TLS client certificates (this key needs to have no password)"},
 		&cli.StringFlag{Name: "client-cert-p12", Aliases: []string{"ccp12"}, Usage: "a p12 file to use for options TLS client certificates"},
 		&cli.StringFlag{Name: "client-cert-p12-password", Aliases: []string{"ccp12p"}, Usage: "the password to the p12 file"},
+		&cli.StringFlag{Name: "interface", Aliases: []string{"iface"}, Usage: "specify network interface to use. Can't be used with local-ip"},
+		&cli.StringFlag{Name: "local-ip", Usage: "specify local ip of network interface to use. Can't be used with interface"},
 	}
 }
 
@@ -81,6 +84,27 @@ func ParseBasicHTTPOptions(c *cli.Context) (libgobuster.BasicHTTPOptions, error)
 		}
 	}
 
+	iface := c.String("interface")
+	localIP := c.String("local-ip")
+	if iface != "" && localIP != "" {
+		return opts, fmt.Errorf("can not set both interface and local-ip")
+	}
+
+	switch {
+	case iface != "":
+		a, err := getLocalAddrFromInterface(iface)
+		if err != nil {
+			return opts, err
+		}
+		opts.LocalAddr = a
+	case localIP != "":
+		a, err := net.ResolveIPAddr("ip", localIP)
+		if err != nil {
+			return opts, err
+		}
+		opts.LocalAddr = a
+	}
+
 	return opts, nil
 }
 
@@ -238,3 +262,28 @@ func ParseGlobalOptions(c *cli.Context) (libgobuster.Options, error) {
 	opts.Debug = c.Bool("debug")
 	return opts, nil
 }
+
+func getLocalAddrFromInterface(iface string) (net.Addr, error) {
+	ifaces, err := net.Interfaces()
+	if err != nil {
+		return nil, fmt.Errorf("could not get interfaces: %w", err)
+	}
+
+	for _, i := range ifaces {
+		if i.Name == iface {
+			addrs, err := i.Addrs()
+			if err != nil {
+				return nil, fmt.Errorf("could not get local addrs for iface %s: %w", i.Name, err)
+			}
+			for _, a := range addrs {
+				switch v := a.(type) {
+				case *net.IPAddr:
+					return v, nil
+				case *net.IPNet:
+					return v, nil
+				}
+			}
+		}
+	}
+	return nil, fmt.Errorf("could not find ip for interface %s", iface)
+}

gobusterdir/gobusterdir.go

@@ -368,6 +368,12 @@ func (d *GobusterDir) GetConfigString() (string, error) {
 		}
 	}
 
+	if o.BasicHTTPOptions.LocalAddr != nil {
+		if _, err := fmt.Fprintf(tw, "[+] Local IP:\t%s\n", o.BasicHTTPOptions.LocalAddr); err != nil {
+			return "", err
+		}
+	}
+
 	if o.HideLength {
 		if _, err := fmt.Fprintf(tw, "[+] Show length:\tfalse\n"); err != nil {
 			return "", err

gobusterfuzz/gobusterfuzz.go

@@ -266,6 +266,12 @@ func (d *GobusterFuzz) GetConfigString() (string, error) {
 		}
 	}
 
+	if o.BasicHTTPOptions.LocalAddr != nil {
+		if _, err := fmt.Fprintf(tw, "[+] Local IP:\t%s\n", o.BasicHTTPOptions.LocalAddr); err != nil {
+			return "", err
+		}
+	}
+
 	if o.Username != "" {
 		if _, err := fmt.Fprintf(tw, "[+] Auth User:\t%s\n", o.Username); err != nil {
 			return "", err

gobustergcs/gobustersgcs.go

@@ -245,6 +245,12 @@ func (s *GobusterGCS) GetConfigString() (string, error) {
 		}
 	}
 
+	if o.BasicHTTPOptions.LocalAddr != nil {
+		if _, err := fmt.Fprintf(tw, "[+] Local IP:\t%s\n", o.BasicHTTPOptions.LocalAddr); err != nil {
+			return "", err
+		}
+	}
+
 	if _, err := fmt.Fprintf(tw, "[+] Timeout:\t%s\n", o.Timeout.String()); err != nil {
 		return "", err
 	}

gobusters3/gobusters3.go

@@ -236,6 +236,12 @@ func (s *GobusterS3) GetConfigString() (string, error) {
 		}
 	}
 
+	if o.BasicHTTPOptions.LocalAddr != nil {
+		if _, err := fmt.Fprintf(tw, "[+] Local IP:\t%s\n", o.BasicHTTPOptions.LocalAddr); err != nil {
+			return "", err
+		}
+	}
+
 	if _, err := fmt.Fprintf(tw, "[+] Timeout:\t%s\n", o.Timeout.String()); err != nil {
 		return "", err
 	}

gobustervhost/gobustervhost.go

@@ -266,6 +266,12 @@ func (v *GobusterVhost) GetConfigString() (string, error) {
 		}
 	}
 
+	if o.BasicHTTPOptions.LocalAddr != nil {
+		if _, err := fmt.Fprintf(tw, "[+] Local IP:\t%s\n", o.BasicHTTPOptions.LocalAddr); err != nil {
+			return "", err
+		}
+	}
+
 	if o.Username != "" {
 		if _, err := fmt.Fprintf(tw, "[+] Auth User:\t%s\n", o.Username); err != nil {
 			return "", err

libgobuster/http.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"net/http/httputil"
 	"net/url"
@@ -79,15 +80,28 @@ func NewHTTPClient(opt *HTTPOptions, logger *Logger) (*HTTPClient, error) {
 		tlsConfig.Certificates = []tls.Certificate{*opt.TLSCertificate}
 	}
 
+	transport := &http.Transport{
+		Proxy:               proxyURLFunc,
+		MaxIdleConns:        100,
+		MaxIdleConnsPerHost: 100,
+		TLSClientConfig:     &tlsConfig,
+	}
+
+	// set specific network interface
+	if opt.LocalAddr != nil {
+		dialer := &net.Dialer{
+			Timeout:   opt.Timeout,
+			LocalAddr: opt.LocalAddr,
+		}
+		transport.DialContext = dialer.DialContext
+	}
+
 	client.client = &http.Client{
 		Timeout:       opt.Timeout,
 		CheckRedirect: redirectFunc,
-		Transport: &http.Transport{
-			Proxy:               proxyURLFunc,
-			MaxIdleConns:        100,
-			MaxIdleConnsPerHost: 100,
-			TLSClientConfig:     &tlsConfig,
-		}}
+		Transport:     transport,
+	}
+
 	client.username = opt.Username
 	client.password = opt.Password
 	client.userAgent = opt.UserAgent

libgobuster/options.go

@@ -1,6 +1,8 @@
 package libgobuster
 
-import "time"
+import (
+	"time"
+)
 
 // Options holds all options that can be passed to libgobuster
 type Options struct {

libgobuster/options_http.go

@@ -2,6 +2,7 @@ package libgobuster
 
 import (
 	"crypto/tls"
+	"net"
 	"time"
 )
 
@@ -14,6 +15,7 @@ type BasicHTTPOptions struct {
 	RetryOnTimeout  bool
 	RetryAttempts   int
 	TLSCertificate  *tls.Certificate
+	LocalAddr       net.Addr
 }
 
 // HTTPOptions is the struct to pass in all http options to Gobuster