Cablej master (#232)

* Add support to HTTP for setting local interface

* Add net import

* use correct flag

* better CLI flag name

* Remove logged `\n`

* Remove extranneous if statement

config.go

@@ -1,6 +1,7 @@
 package zgrab2
 
 import (
+	"net"
 	"net/http"
 	"os"
 	"runtime"
@@ -16,7 +17,7 @@ type Config struct {
 	InputFileName      string          `short:"f" long:"input-file" default:"-" description:"Input filename, use - for stdin"`
 	MetaFileName       string          `short:"m" long:"metadata-file" default:"-" description:"Metadata filename, use - for stderr"`
 	LogFileName        string          `short:"l" long:"log-file" default:"-" description:"Log filename, use - for stderr"`
-	Interface          string          `short:"i" long:"interface" description:"Network interface to send on"`
+	LocalAddress       string          `long:"source-ip" description:"Local source IP address to use for making connections"`
 	Senders            int             `short:"s" long:"senders" default:"1000" description:"Number of send goroutines to use"`
 	Debug              bool            `long:"debug" description:"Include debug fields in the output."`
 	GOMAXPROCS         int             `long:"gomaxprocs" default:"0" description:"Set GOMAXPROCS"`
@@ -30,6 +31,7 @@ type Config struct {
 	logFile            *os.File
 	inputTargets       InputTargetsFunc
 	outputResults      OutputResultsFunc
+	localAddr          *net.TCPAddr
 }
 
 // SetInputFunc sets the target input function to the provided function.
@@ -61,6 +63,14 @@ func validateFrameworkConfiguration() {
 	}
 	SetInputFunc(InputTargetsCSV)
 
+	if config.LocalAddress != "" {
+		parsed := net.ParseIP(config.LocalAddress)
+		if parsed == nil {
+			log.Fatalf("Error parsing local interface %s as IP", config.LocalAddress)
+		}
+		config.localAddr = &net.TCPAddr{parsed, 0, ""}
+	}
+
 	if config.InputFileName == "-" {
 		config.inputFile = os.Stdin
 	} else {

conn.go

@@ -219,10 +219,10 @@ func (c *TimeoutConnection) SetDefaults() *TimeoutConnection {
 // NewTimeoutConnection returns a new TimeoutConnection with the appropriate defaults.
 func NewTimeoutConnection(ctx context.Context, conn net.Conn, timeout, readTimeout, writeTimeout time.Duration, bytesReadLimit int) *TimeoutConnection {
 	ret := (&TimeoutConnection{
-		Conn:         conn,
-		Timeout:      timeout,
-		ReadTimeout:  readTimeout,
-		WriteTimeout: writeTimeout,
+		Conn:           conn,
+		Timeout:        timeout,
+		ReadTimeout:    readTimeout,
+		WriteTimeout:   writeTimeout,
 		BytesReadLimit: bytesReadLimit,
 	}).SetDefaults()
 	if ctx == nil {
@@ -298,6 +298,10 @@ func (d *Dialer) DialContext(ctx context.Context, network, address string) (net.
 	// ensure that our aux dialer is up-to-date; copied from http/transport.go
 	d.Dialer.Timeout = d.getTimeout(d.ConnectTimeout)
 	d.Dialer.KeepAlive = d.Timeout
+
+	// Copy over the source IP if set, or nil
+	d.Dialer.LocalAddr = config.localAddr
+
 	dialContext, cancelDial := context.WithTimeout(ctx, d.Dialer.Timeout)
 	defer cancelDial()
 	conn, err := d.Dialer.DialContext(dialContext, network, address)

go.mod

@@ -3,8 +3,6 @@ module github.com/zmap/zgrab2
 go 1.12
 
 require (
-	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
-	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/prometheus/client_golang v1.1.0
 	github.com/sirupsen/logrus v1.4.2
 	github.com/zmap/zcrypto v0.0.0-20190729165852-9051775e6a2e