update

.github/workflows/update.yml

@@ -35,7 +35,7 @@ jobs:
 
       - name: commit changes
         # need to override the default shell so we can check
-        # for error codes. Otherwise it will always fail if
+        # for error codes. Otherwise, it will always fail if
         # one command returns an error code other than 0
         shell: bash --noprofile --norc -o pipefail {0}
         run: |

Readme.md

@@ -162,7 +162,7 @@ return the defaults.
 
 This command tries all passwords from a given file for a username via the TURN protocol (UDP). This can be useful when
 analysing a pcap where you can see the username but not the password.
-Please note that an offline bruteforce is much more faster in this case.
+Please note that an offline bruteforce is much faster in this case.
 
 ### Options
 
@@ -226,9 +226,9 @@ If it works you should see big loads of memory coming in, otherwise you will onl
 
 ## udp-scanner
 
-If a TURN server allows UDP connections to targets this scanner can be used to scan all private ip ranges and send them
+If a TURN server allows UDP connections to internal targets this scanner can be used to scan all private ip ranges and send them
 SNMP and DNS requests. As this checks a lot of IPs this can take multiple days to complete so use with caution or
-specify smaller targets via the parameters. You need to supply a SNMP community string that will be tried and a domain
+specify smaller targets via the parameters. You need to supply an SNMP community string that will be tried and a domain
 name that will be resolved on each IP. For the domain name you can for example use burp collaborator.
 
 ### Options
@@ -286,9 +286,9 @@ First step is to get the required data. I suggest to launch Wireshark in the bac
 to collect all HTTP and Websocket traffic. Next search your burp history for some keywords related to TURN like `3478`,
 `password`, `credential` and `username` (be sure to also check the websocket tab for these keywords). This might reveal
 the turn server and the protocol (UDP and TCP endpoints might have different ports) and the credentials used to connect.
-If you can't find the data in burp start looking at wireshark to identify the traffic. If it's on a non standard port (
+If you can't find the data in burp start looking at wireshark to identify the traffic. If it's on a nonstandard port (
 anything else then 3478) decode the protocol in Wireshark via a right click as `STUN`. This should show you the username
-used to connect and you can use this information to search burps history even further for the required data. Please note
+used to connect, and you can use this information to search burps history even further for the required data. Please note
 that Wireshark can't show you the password as the password is used to hash some package contents so it can not be
 reversed.
 

internal/helper/connection.go

@@ -48,7 +48,8 @@ func connectionRead(ctx context.Context, r *bufio.Reader, maxSizeToRead *int, ti
 			if err != nil {
 				if err != io.EOF {
 					// also return read data on timeout so caller can use it
-					if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
+					var netErr net.Error
+					if errors.As(err, &netErr) && netErr.Timeout() {
 						return ret, ErrTimeout
 					}
 					return nil, err
@@ -86,10 +87,9 @@ func ConnectionWrite(ctx context.Context, conn net.Conn, data []byte, timeout ti
 		default:
 			written, err = conn.Write(data[written:toWriteLeft])
 			if err != nil {
-				if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
+				var netErr net.Error
+				if errors.As(err, &netErr) && netErr.Timeout() {
 					return ErrTimeout
-				} else {
-					return err
 				}
 			}
 			if written == toWriteLeft {

internal/helper/helper.go

@@ -48,8 +48,7 @@ func IsPrivateIP(ip netip.Addr) bool {
 // numbers (16,383 possible values).
 func RandomChannelNumber() ([]byte, error) {
 	token := make([]byte, 2)
-	valid := false
-	for !valid {
+	for {
 		if _, err := cryptorand.Read(token); err != nil {
 			return nil, err
 		}

internal/socksimplementations/socksturntcphandler.go

@@ -30,7 +30,7 @@ type SocksTurnTCPHandler struct {
 	nonce                  string
 }
 
-// PreHandler connects to the STUN server, sets the connection up and returns the data connections
+// Init connects to the STUN server, sets the connection up and returns the data connections
 func (s *SocksTurnTCPHandler) Init(ctx context.Context, request socks.Request) (context.Context, io.ReadWriteCloser, *socks.Error) {
 	var target netip.Addr
 	var err error
@@ -129,8 +129,8 @@ func (s *SocksTurnTCPHandler) ReadFromClient(ctx context.Context, client io.Read
 	for {
 		// anonymous func for defer
 		// this might not be the fastest, but it does the trick
-		// in this case the timeout is per buffer read/write to support long
-		// running downloads.
+		// in this case the timeout is per buffer read/write to support
+		// long-running downloads.
 		err := func() error {
 			timeOut := time.Now().Add(s.Timeout)
 
@@ -174,8 +174,8 @@ func (s *SocksTurnTCPHandler) ReadFromRemote(ctx context.Context, remote io.Read
 	for {
 		// anonymous func for defer
 		// this might not be the fastest, but it does the trick
-		// in this case the timeout is per buffer read/write to support long
-		// running downloads.
+		// in this case the timeout is per buffer read/write to support
+		// long-running downloads.
 		err := func() error {
 			timeOut := time.Now().Add(s.Timeout)
 
@@ -214,8 +214,8 @@ func (s *SocksTurnTCPHandler) ReadFromRemote(ctx context.Context, remote io.Read
 	}
 }
 
-// Cleanup closes the stored control connection
-func (s *SocksTurnTCPHandler) Close(ctx context.Context) error {
+// Close closes the stored control connection
+func (s *SocksTurnTCPHandler) Close(_ context.Context) error {
 	if s.ControlConnection != nil {
 		return s.ControlConnection.Close()
 	}

internal/stun.go

@@ -56,7 +56,7 @@ func (s *Stun) String() string {
 
 // Serialize converts the object into a byte stream
 func (s *Stun) Serialize() ([]byte, error) {
-	// first start with the attributes so we can calculate the message length afterwards
+	// first start with the attributes so we can calculate the message length afterward
 	var attributes []byte
 	authenticated := false
 	for _, a := range s.Attributes {

internal/types_turn.go

@@ -5,7 +5,7 @@ package internal
 0x004  :  Refresh           (only request/response semantics defined)
 0x006  :  Send              (only indication semantics defined)
 0x007  :  Data              (only indication semantics defined)
-0x008  :  CreatePermission  (only request/response semantics defined
+0x008  :  CreatePermission  (only request/response semantics defined)
 0x009  :  ChannelBind       (only request/response semantics defined)
 
 This STUN extension defines the following new attributes: