Added garbage in the transmitted RadioTap()

Issue: Garbage accompanies the transmitted packets. Severity: functionality of libtins

Description:

Dear @mfontanini,

Packets crafted by libtins (pulled today Mon 8. Mar 2021) are accompanied with some garbage when transmitted over. Below you can find more information about the issue I am facing.

Best, Masoud

WLAN Adapter

ALFA AWUS036ACH with driver version 5.7.0

OS

Linux kali 5.10.0-kali3-amd64 #1 SMP Debian 5.10.13-1kali1 (2021-02-08) x86_64 GNU/Linux.

Compiler

g++ (Debian 10.2.1-6) 10.2.1 20210110 cmake version 3.18.4

Dependancies

tcpdump version 5.0.0-PRE-GIT libpcap version 1.11.0-PRE-GIT (with TPACKET_V3) OpenSSL 1.1.1j 16 Feb 2021 bison (GNU Bison) 3.7.5 flex++ 2.6.4

Code to craft an open authentication packet:

Dot11Authentication auth( ap_addr, sta_addr ); auth.addr3( ap_addr ); auth.auth_algorithm( 0 ); auth.auth_seq_number( 0x0001 ); auth.status_code( 0x0000 ); auto radio = RadioTap() / auth;

Code to send the packet:

PacketSender sender( iface ); sender.send( radio );

Code to save the packet:

PacketWriter w( "auth.pcap", PacketWriter::RADIOTAP ); w.write( radio );

Dumped packet in Wireshark:

Frame 1: 60 bytes on wire (480 bits), 60 bytes captured (480 bits)

Encapsulation type: IEEE 802.11 plus radiotap radio header (23)
Arrival Time: Mar  8, 2021 16:43:54.059643000 CET
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1615218234.059643000 seconds
[Time delta from previous captured frame: 0.000000000 seconds]
[Time delta from previous displayed frame: 0.000000000 seconds]
[Time since reference or first frame: 0.000000000 seconds]
Frame Number: 1
Frame Length: 60 bytes (480 bits)
Capture Length: 60 bytes (480 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: radiotap:wlan_radio:wlan]
Radiotap Header v0, Length 26 Header revision: 0 Header pad: 0 Header length: 26 Present flags MAC timestamp: 0 Flags: 0x10 Channel frequency: 2412 [BG 1] Channel flags: 0x00a0, Complementary Code Keying (CCK), 2 GHz spectrum Antenna signal: -50 dBm Antenna: 0 RX flags: 0x0000 .... .... .... .... .... ..0. = Bad PLCP: False 802.11 radio information PHY type: 802.11b (HR/DSSS) (4) Short preamble: False Channel: 1 Frequency: 2412MHz Signal strength (dBm): -50 dBm TSF timestamp: 0 IEEE 802.11 Authentication, Flags: ........C Type/Subtype: Authentication (0x000b) Frame Control Field: 0xb000 .000 0000 0000 0000 = Duration: 0 microseconds Receiver address: AP_Manufacturer (sc:ra:mb:le:dm:ac) Destination address: AP_Manufacturer (sc:ra:mb:le:dm:ac) Transmitter address: STA_Manufacturer (ca:md:el:bm:ar:cs) Source address: STA_Manufacturer (ca:md:el:bm:ar:cs) BSS Id: 00:00:00_00:00:00 (00:00:00:00:00:00) .... .... .... 0000 = Fragment number: 0 0000 0000 0000 .... = Sequence number: 0 Frame check sequence: 0x55d563c4 [unverified] [FCS Status: Unverified] IEEE 802.11 Wireless Management Fixed parameters (6 bytes)
    Authentication Algorithm: Open System (0)
    Authentication SEQ: 0x0001
    Status code: Successful (0x0000)

Transmitted packet captured by Wireshark

Frame 18: 63 bytes on wire (504 bits), 63 bytes captured (504 bits) on interface XXXXXXX, id N

Interface id: 0 (en0)
Encapsulation type: IEEE 802.11 plus radiotap radio header (23)
Arrival Time: Mar  8, 2021 17:30:21.394682000 CET
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1615221021.394682000 seconds
[Time delta from previous captured frame: 903.600193000 seconds]
[Time delta from previous displayed frame: 903.600193000 seconds]
[Time since reference or first frame: 2373.833769000 seconds]
Frame Number: 18
Frame Length: 63 bytes (504 bits)
Capture Length: 63 bytes (504 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: radiotap:wlan_radio:wlan]
Radiotap Header v0, Length 25' Header revision: 0 Header pad: 0 Header length: 25 Present flags MAC timestamp: 2385617569 Flags: 0x10 Data Rate: 1.0 Mb/s Channel frequency: 2412 [BG 1] Channel flags: 0x0480, 2 GHz spectrum, Dynamic CCK-OFDM Antenna signal: -11 dBm Antenna noise: -81 dBm Antenna: 0 802.11 radio information PHY type: 802.11g (ERP) (6) Short preamble: False Proprietary mode: None (0) Data rate: 1.0 Mb/s Channel: 1 Frequency: 2412MHz Signal strength (dBm): -11 dBm Noise level (dBm): -81 dBm Signal/noise ratio (dB): 70 dB TSF timestamp: 2385617569 [Duration: 496µs] IEEE 802.11 Authentication, Flags: ........C Type/Subtype: Authentication (0x000b) Frame Control Field: 0xb000 .000 0001 0011 1010 = Duration: 314 microseconds Receiver address: AP_Manufacturer (sc:ra:mb:le:dm:ac) Destination address: AP_Manufacturer (sc:ra:mb:le:dm:ac) Transmitter address: STA_Manufacturer (ca:md:el:bm:ar:cs) Source address: STA_Manufacturer (ca:md:el:bm:ar:cs) BSS Id: AP_Manufacturer (sc:ra:mb:le:dm:ac) .... .... .... 0000 = Fragment number: 0 0001 0010 1100 .... = Sequence number: 300 Frame check sequence: 0x75a718ad [unverified] [FCS Status: Unverified] IEEE 802.11 Wireless Management Fixed parameters (6 bytes)`
   Authentication Algorithm: Open System (0)
   Authentication SEQ: 0x0001
   Status code: Successful (0x0000)
Tagged parameters (4 bytes) Tag: Diagnostic Report
       Tag Number: Diagnostic Report (81)
       Tag length: 115
[Malformed Packet: IEEE 802.11] [Expert Info (Error/Malformed): Malformed Packet (Exception occurred)] [Malformed Packet (Exception occurred)] [Severity level: Error] [Group: Malformed]

mfontanini / libtins