tools: migrate flags.Parse tools to transport

Four tools that already used flags.Parse (and therefore already had
-proxy registered transparently) still reached out via net.Dial* or
ran DNS resolution past the proxy. Migrate the network calls:

- tools/GetADComputers: custom net.Resolver now dials via
  transport.DialContext, so UDP DNS through the DC surfaces
  ErrUDPUnderProxy cleanly rather than bypassing -proxy.
- tools/changepasswd: kpasswd TCP dial now uses transport.DialTimeout.
- tools/smbexec: getLocalIP() short-circuits when
  transport.IsProxyConfigured(). The "dial UDP to find the local
  source address" trick has no meaning when traffic flows through a
  SOCKS5 proxy.
- tools/raiseChild: the DNS forest-FQDN fallback (net.LookupHost) is
  skipped under -proxy with a message pointing the user to -parent-dc,
  since net.LookupHost goes to the OS resolver and would leak DNS.

tools/GetADComputers/main.go

@@ -28,6 +28,7 @@ import (
 	"gopacket/pkg/flags"
 	"gopacket/pkg/ldap"
 	"gopacket/pkg/session"
+	"gopacket/pkg/transport"
 )
 
 var (
@@ -161,12 +162,12 @@ func resolveHostname(hostname, dnsServer string) string {
 		return ""
 	}
 
-	// Use custom resolver to query the DC's DNS
+	// Custom resolver using the DC's DNS. Under -proxy, UDP DNS cannot be
+	// tunneled via SOCKS5; callers should pass an IP directly in that case.
 	resolver := &net.Resolver{
 		PreferGo: true,
 		Dial: func(ctx context.Context, network, address string) (net.Conn, error) {
-			d := net.Dialer{Timeout: 2 * time.Second}
-			return d.DialContext(ctx, "udp", dnsServer+":53")
+			return transport.DialContext(ctx, network, dnsServer+":53")
 		},
 	}
 

tools/changepasswd/main.go

@@ -20,7 +20,6 @@ import (
 	"fmt"
 	"io"
 	"log"
-	"net"
 	"os"
 	"strings"
 	"time"
@@ -33,6 +32,7 @@ import (
 	"gopacket/pkg/ldap"
 	"gopacket/pkg/session"
 	"gopacket/pkg/smb"
+	"gopacket/pkg/transport"
 
 	goldap "github.com/go-ldap/ldap/v3"
 	krbclient "github.com/jcmturner/gokrb5/v8/client"
@@ -616,7 +616,7 @@ func doKpasswd(opts *flags.Options, target session.Target, targetUsername, targe
 // sendKpasswd sends a kpasswd request to the KDC on TCP port 464 and returns the response.
 func sendKpasswd(kdc string, data []byte) ([]byte, error) {
 	addr := fmt.Sprintf("%s:464", kdc)
-	conn, err := net.DialTimeout("tcp", addr, 10*time.Second)
+	conn, err := transport.DialTimeout("tcp", addr, 10)
 	if err != nil {
 		return nil, fmt.Errorf("failed to connect to kpasswd %s: %v", addr, err)
 	}

tools/raiseChild/main.go

@@ -35,6 +35,7 @@ import (
 	"gopacket/pkg/kerberos"
 	"gopacket/pkg/session"
 	"gopacket/pkg/smb"
+	"gopacket/pkg/transport"
 )
 
 var (
@@ -356,7 +357,14 @@ func discoverParentDC(forestFQDN string, target session.Target, creds *session.C
 		}
 	}
 
-	// Fallback: DNS resolution of forest FQDN
+	// Fallback: DNS resolution of forest FQDN. Disabled under -proxy because
+	// net.LookupHost uses the OS resolver, which would silently bypass the
+	// configured SOCKS5 proxy and leak DNS. Callers should pass the parent DC
+	// explicitly via -parent-dc in that case.
+	if transport.IsProxyConfigured() {
+		fmt.Println("[!] DNS fallback disabled under -proxy, pass parent DC explicitly via -parent-dc")
+		return ""
+	}
 	addrs, err := net.LookupHost(forestFQDN)
 	if err == nil && len(addrs) > 0 {
 		fmt.Printf("[*] DNS resolved %s to %s\n", forestFQDN, addrs[0])

tools/smbexec/main.go

@@ -36,6 +36,7 @@ import (
 	"gopacket/pkg/flags"
 	"gopacket/pkg/session"
 	"gopacket/pkg/smb"
+	"gopacket/pkg/transport"
 )
 
 var (
@@ -446,8 +447,15 @@ func (e *SMBExec) finish() {
 	}
 }
 
-// getLocalIP determines the local IP address used to reach the target host
+// getLocalIP determines the local IP address used to reach the target host.
+// Under -proxy the concept doesn't apply (traffic flows via the proxy, not
+// directly from this host), so we return "" and let the caller fall back.
+// The UDP socket here doesn't actually send packets — it just asks the kernel
+// which source address would be picked for a hypothetical connection.
 func getLocalIP(targetHost string) string {
+	if transport.IsProxyConfigured() {
+		return ""
+	}
 	conn, err := net.Dial("udp", targetHost+":445")
 	if err != nil {
 		return ""