1<!-- 2Author: Xianjun jiao 3SPDX-FileCopyrightText: 2021 UGent 4SPDX-License-Identifier: AGPL-3.0-or-later 5--> 6 7[ACM WiSec 2021. Openwifi CSI fuzzer for authorized sensing and covert channels](https://dl.acm.org/doi/pdf/10.1145/3448300.3468255) 8 9CSI (Channel State Information) of WiFi systems is available in some WiFi chips and can be used for sensing the environment (keystrokes, people, object) passively and secretly. 10 11## Concept 12 13How could a CSI fuzzer stop unauthorized sensing? 14 15 16 17CSI fuzzer implementation principle. 18 19 20 21## Demo instructions 22 23Thanks to the full-duplex capability and CSI extraction feature of openwifi, you can monitor the artificial channel response via [side channel](./csi.md) by Tx-Rx over the air coupling without affecting the normal operation/traffic of openwifi. Before fuzzing the CSI, please follow [WiFi CSI radar via self CSI capturing](radar-self-csi.md) app note to setup normal self CSI monitoring. 24 25Then, start another ssh session to the openwifi board: 26``` 27ssh [email protected] 28(password: openwifi) 29 30cd openwifi 31 32./csi_fuzzer_scan.sh 1 33(CSI fuzzer applies possible artificial CSI by scanning all values) 34(csi_fuzzer.sh is called. Please read both scripts to understand these commands) 35``` 36 37Now you should see that CSI keeps changing like in this [video](https://youtu.be/aOPYwT77Qdw). 38 39# Further explanation on parameters 40 41CSI fuzzer in openwifi system architecture and related commands. 42 43 44 45# Example fuzzed CSI 46 47CSI self-monitoring before fuzzing. 48 49 50 51CSI self-monitoring after fuzzing command: `./csi_fuzzer.sh 1 45 0 13` 52 53 54 55`csi_fuzzer_scan.sh` can scan the c1 and c2 in different styles/modes by calling `csi_fuzzer.sh`. 56
