Three ways in through peripherals

sudo apt install build-essential linux-headers-$(uname -r) dosfstools roamswitch clamav clamav-daemon
mkdir -p ~/dhcd && cd ~/dhcd
curl -fsSL -o dummy_hcd.c https://raw.githubusercontent.com/torvalds/linux/v$(uname -r | cut -d. -f1,2)/drivers/usb/gadget/udc/dummy_hcd.c
echo "obj-m := dummy_hcd.o" > Makefile
make -C /lib/modules/$(uname -r)/build M=$PWD modules
sudo mkdir -p /opt/fakeusb && sudo cp dummy_hcd.ko /opt/fakeusb/
sudo systemctl stop clamav-freshclam && sudo freshclam && sudo systemctl restart clamav-daemon

sudo truncate -s 64M /opt/fakeusb/stick.img
sudo mkfs.vfat -n PRACTICE /opt/fakeusb/stick.img
sudo mkdir -p /mnt/img /mnt/stick && sudo mount -o loop /opt/fakeusb/stick.img /mnt/img
printf '%s' 'X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*' | sudo tee /mnt/img/eicar.com >/dev/null
echo hello | sudo tee /mnt/img/readme.txt >/dev/null
sudo umount /mnt/img

#!/bin/sh
# fakeusb storage|keyboard plug|unplug : a virtual USB device on dummy_hcd (practice only)
set -e
G=/sys/kernel/config/usb_gadget
kind=$1; act=$2
modprobe libcomposite
mountpoint -q /sys/kernel/config || mount -t configfs none /sys/kernel/config
lsmod | grep -q '^dummy_hcd' || insmod /opt/fakeusb/dummy_hcd.ko
case "$kind" in
  storage) d=$G/practice_stick; pid=0x0001; prod="Practice Stick"; modprobe usb_f_mass_storage;;
  keyboard) d=$G/practice_kbd; pid=0x0002; prod="Practice Keyboard"; modprobe usb_f_hid;;
  *) echo "usage: fakeusb storage|keyboard plug|unplug"; exit 2;;
esac
if [ "$act" = unplug ]; then
  [ -e $d/UDC ] && echo "" > $d/UDC 2>/dev/null || true
  echo unplugged; exit 0
fi
if [ ! -d $d ]; then
  mkdir -p $d && cd $d
  echo 0x1209 > idVendor; echo $pid > idProduct; echo 0x0100 > bcdDevice; echo 0x0200 > bcdUSB
  mkdir -p strings/0x409
  echo "Practice" > strings/0x409/manufacturer; echo "$prod" > strings/0x409/product; echo "PRACTICE0001" > strings/0x409/serialnumber
  mkdir -p configs/c.1/strings/0x409; echo "practice" > configs/c.1/strings/0x409/configuration; echo 100 > configs/c.1/MaxPower
  if [ "$kind" = storage ]; then
    mkdir -p functions/mass_storage.0
    echo 1 > functions/mass_storage.0/lun.0/removable
    echo /opt/fakeusb/stick.img > functions/mass_storage.0/lun.0/file
    ln -s functions/mass_storage.0 configs/c.1/
  else
    mkdir -p functions/hid.usb0; cd functions/hid.usb0
    echo 1 > protocol; echo 1 > subclass; echo 8 > report_length
    python3 -c 'import sys; sys.stdout.buffer.write(bytes.fromhex("05010906a101050719e029e71500250175019508810295017508810395057501050819012905910295017503910395067508150025650507190029658100c0"))' > report_desc
    cd $d; ln -s functions/hid.usb0 configs/c.1/
  fi
fi
cd $d
# one UDC: unbind the other gadget first
for o in $G/*; do [ "$o" != "$d" ] && [ -n "$(cat $o/UDC 2>/dev/null)" ] && echo "" > $o/UDC; done
echo dummy_udc.0 > UDC
echo plugged

sudo fakeusb storage plug
sleep 3
lsusb | grep 1209

mkdir -p ~/.config/roamswitch
cat > ~/.config/roamswitch/config.json <<'J'
{
  "language": "en",
  "allowed_usb_devices": [
    {"deviceIdentifier": "05ac:8105", "displayName": "Virtual USB Keyboard", "dateAdded": "2026-11-05 09:00"}
  ]
}
J
chmod 600 ~/.config/roamswitch/config.json
sudo systemctl restart roamswitch

sudo fakeusb storage plug
sleep 3
sudo dmesg | tail -1
cat /run/roamswitch/state.json
cat /sys/bus/usb/devices/usb3/authorized_default
cat /sys/bus/usb/devices/3-1/authorized
lsblk -S
roamswitch notifications | head -8

python3 -c "
import json
for a in json.load(open('/run/roamswitch/approvals.json')): print(a['kind'], a['device_id']); print(a['title']); print(a['body'])"

allow_usb() { python3 - "$1" "$2" <<'P'
import json,os,sys
p=os.path.expanduser('~/.config/roamswitch/config.json')
c=json.load(open(p))
c['allowed_usb_devices'].append({"deviceIdentifier":sys.argv[1],"displayName":sys.argv[2],"dateAdded":"2026-11-05 09:40"})
json.dump(c,open(p,'w'),ensure_ascii=False,indent=2)
P
}
allow_usb 1209:0001 "Practice Stick"
sleep 6
cat /sys/bus/usb/devices/3-1/authorized
lsblk -S
sudo mount -o ro /dev/sda /mnt/stick && ls /mnt/stick
sleep 15
roamswitch notifications | sed -n 4,9p

sudo umount /mnt/stick
sudo fakeusb storage unplug
sleep 5
echo PRACTICE9999 | sudo tee /sys/kernel/config/usb_gadget/practice_stick/strings/0x409/serialnumber
sudo fakeusb storage plug
sleep 6
cat /sys/bus/usb/devices/3-1/authorized
sudo journalctl -u roamswitch --since -15s -o cat | grep fingerprint
roamswitch notifications | sed -n 4,7p
python3 -c "
import json
for a in json.load(open('/run/roamswitch/approvals.json')): print(a['kind'], a['device_id']); print(a['title']); print(a['body'])"

#!/usr/bin/env python3
# typekeys.py: send "echo practice" + Enter through /dev/hidg0, one key every 5 ms (a script, not a person)
import sys, time
KEYS = {c: 0x04 + i for i, c in enumerate("abcdefghijklmnopqrstuvwxyz")}
KEYS[" "] = 0x2c; KEYS["\n"] = 0x28
gap = float(sys.argv[1]) if len(sys.argv) > 1 else 0.005
with open("/dev/hidg0", "wb", buffering=0) as f:
    for ch in "echo practice\n":
        f.write(bytes([0, 0, KEYS[ch], 0, 0, 0, 0, 0]))
        f.write(bytes(8))
        time.sleep(gap)
print("sent", len("echo practice\n"), "keys")

#!/usr/bin/env python3
# readkeys.py EVENT SECONDS: count key presses that reach this reader (no grab of its own)
import os, select, struct, sys, time
fd = os.open(sys.argv[1], os.O_RDONLY | os.O_NONBLOCK)
end = time.time() + float(sys.argv[2]); n = 0
while time.time() < end:
    r, _, _ = select.select([fd], [], [], 0.2)
    if r:
        data = os.read(fd, 24 * 64)
        for i in range(0, len(data), 24):
            _, _, typ, code, val = struct.unpack("llHHi", data[i:i + 24])
            if typ == 1 and val == 1:
                n += 1
print("key presses seen:", n)

sudo fakeusb keyboard plug
sleep 6
EV=$(grep -A6 'Name="Practice Practice Keyboard"' /proc/bus/input/devices | sed -n 's/.*Handlers=.*\(event[0-9]*\).*/\1/p')
(sudo readkeys.py /dev/input/$EV 5 &) ; sleep 1; sudo timeout 10 typekeys.py
sleep 6
roamswitch notifications | sed -n 4,13p

allow_usb 1209:0002 "Practice Keyboard"
sleep 6
(sudo readkeys.py /dev/input/$EV 5 &) ; sleep 1; sudo timeout 10 typekeys.py 0.15
cat /run/roamswitch/approvals.json

setk() { python3 - "$1" "$2" <<'P'
import json,os,sys
p=os.path.expanduser('~/.config/roamswitch/config.json')
c=json.load(open(p))
k,v=sys.argv[1],sys.argv[2]
if v=='DEL': c.pop(k,None)
else: c[k]=json.loads(v)
json.dump(c,open(p,'w'),ensure_ascii=False,indent=2)
P
}
unallow_usb() { python3 - "$1" <<'P'
import json,os,sys
p=os.path.expanduser('~/.config/roamswitch/config.json')
c=json.load(open(p))
c['allowed_usb_devices']=[d for d in c['allowed_usb_devices'] if d['deviceIdentifier']!=sys.argv[1]]
json.dump(c,open(p,'w'),ensure_ascii=False,indent=2)
P
}
sudo fakeusb keyboard unplug
unallow_usb 1209:0001
setk away_protection_level '"balanced"'
sudo systemctl restart roamswitch; sleep 10
cat /run/roamswitch/state.json
roamswitch guards | grep -i "protection level"

sudo fakeusb storage plug; sleep 6
cat /sys/bus/usb/devices/3-1/authorized
sudo fakeusb storage unplug; sleep 5
setk usb_storage_guard_enabled true; sleep 4
sudo fakeusb storage plug; sleep 6
cat /sys/bus/usb/devices/3-1/authorized
roamswitch notifications | sed -n 4,7p

setk away_protection_level DEL
setk usb_storage_guard_enabled DEL
sudo systemctl restart roamswitch
sudo fakeusb storage unplug
sudo rmmod dummy_hcd

sudo apt install bluez
sudo cp /etc/bluetooth/input.conf /etc/bluetooth/input.conf.orig
sudo cp /etc/bluetooth/main.conf /etc/bluetooth/main.conf.orig
sudo sed -i 's/^#ClassicBondedOnly=true/ClassicBondedOnly=false/' /etc/bluetooth/input.conf
sudo sed -i 's/^#AlwaysPairable = false/AlwaysPairable = true/' /etc/bluetooth/main.conf
roamswitch bluetooth-audit

roamswitch bluetooth-audit --json

sudo mv /etc/bluetooth/input.conf.orig /etc/bluetooth/input.conf
sudo mv /etc/bluetooth/main.conf.orig /etc/bluetooth/main.conf
roamswitch bluetooth-audit | sed -n 5p