Wi-Fi Sniffer

This tool sniffs Wi-Fi data packets between selected client and access point. To sniff data, you have to know password or key used for encryption on given access point (in case of WEP, WPA-PSK and WPA2-PSK). Other encryptions are not supported.

Program flow

1. Start sniffing by setting network interface to use monitor mode and filter Wi-Fi packets.
2. Collect beacon frame and detect used encryption.
3. If WPA or WPA 2 is used, try to deauthenticate client and wait for 4-way auth handshake. If only passive mode is toggled, then program just waits for 4-way auth handshake.
4. Start sniffing data packets and save them to output file.

Requirements

Installing Libpcap and Libtins libraries is required:

sudo apt-get install libpcap-dev libtins-dev

Network adapter with monitor mode support is also required.

Compile and run

To compile program:

mkdir build
cd build
cmake ..
make

To run program and display help:

./sniffer -h

Usage example

For example, if we want to sniff communication between client with MAC adress 3C-3D-BD-60-FE-58 and access point with BSSID F8-87-5F-A8-DD-26 that uses WPA2 encryption with key y8THwDXNwRYH9kdU. In this example, wlp6s0 network interface is used for monitoring mode.

./sniffer -i wlp6s0 -m 3C-3D-BD-60-FE-58 -b F8-87-5F-A8-DD-26 -k y8THwDXNwRYH9kdU

Program arguments

Required

• -i INTERFACE_NAME - Network interface name.
• -m BSSID - Access point BSSID.
• -b CLIENT_MAC - Client MAC address.

Optional

• -h - Prints program help.
• -k ENCRYPTION_KEY - Encryption key.
• -f SAVE_PCAP_FILE_LOCATION - Location of the output pcap file containing captured packets.
• -p - Toggles passive attack only.
• -l - Toggles libpcap library for sniffing.
• -t - Toggles libtins library for sniffing.

Output

Program saves all captured and decrypted data packets in .pcap file.