StreetPass
3DS has a built-in feature StreetPass which lets nearby users to exchange data from games and applications. This is great if you live in a big city where there are a lot of 3DS devices. However, if you live in a small town, you would be lucky to just get a handful of streetpasses monthly.
StreetPass Relay
Due to that, Nintendo introduced another feature called StreetPass Relay. Every 3DS device has a whitelist of public wifi AP which it can automatically connect to. If connected, some data will be sent and stored on Nintendo server. When another 3DS user connects to the same AP, Nintendo server will send the stored data to the latter device. Consequently, 3DS devices don’t have to be in close proximity to exchange data.
The whitelist contains the SSID and MAC of public wifi AP. Thus, some nice people figured out ways to create homemade StreetPass relays by spoofing MAC and SSID.1 The basic idea to create a public wifi AP with the same SSID and MAC as in the whitelist.
For Raspberry Pi, there is SpillPass-Pi2 which work automatically when you plug in. You only need a wifi dongle wlan0 which support mac spoof and a wired internet connection eth0.
My setup is slightly different because I don’t have a wired connection to the home router. What I have is 2 wifi dongles, wlan0 and wlan1. The idea is still the same, but instead of eth0 bridge to wlan0, I have wlan1 connected to the internet and wlan0 as wifi AP. All the traffic are forwarded to/from wlan0 to wlan1.
Setup
I used Raspbian Jessie Lite image. I don’t have external keyboard or monitor so desktop on Raspberry Pi is unnecessary. Installed the image on the SD card by either dd or Etcher, then added your wifi network to /etc/wpa_supplicant/wpa_supplicant.conf.2
#/etc/wpa_supplicant/wpa_supplicant.conf
network={
ssid="testing"
psk="testingPassword"
}Updated and installed softwares:
sudo apt update && sudo apt upgrade
sudo apt -y install hostapd dnsmasq haveged iptable-persistent sqlite3I used this wonderful guide to setup forwarding.
Interfaces
Set wlan0 to a static ip address 10.0.0.1.
#/etc/network/interfaces
auto lo
iface lo inet loopback
iface eth0 inet manual
# AP
allow-hotplug wlan0
iface wlan0 inet static
address 10.0.0.1
netmask 255.255.255.0
# wireless
allow-hotplug wlan1
iface wlan1 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.confTell DHCPCD to ignore wlan0.
#/ect/dhcpcd.conf
denyinterfaces wlan0Hostapd
Hostapd is an user daemon to start up AP. In /etc/default/hostapd, uncomment or add the line DAEMON_CONF=/etc/hostapd/hostapd.conf.
#/etc/hostapd/hostapd.conf
#sample hostapd.conf
#overwrite by homepass.sh
ssid=attwifi
bssid=34:bd:c8:db:79:00
interface=wlan0
driver=nl80211
hw_mode=g
channel=6
auth_algs=3
wpa=0
rsn_pairwise=CCMP
beacon_int=100
macaddr_acl=0
wmm_enabled=0
eap_reauth_period=360000000You can test if AP is working by running sudo hostapd /etct/hostapd/hostapd. You should be able to see attwifi.
I use dnsmasq to map IP addresses to MAC addresses. When 3DS connect to my hotspot, it will be assigned a dynamic IP address. It is also possible to bind 3DS MAC address to a static IP address.
#/etc/dnsmasq.conf
interface=wlan0
except-interface=wlan1
dhcp-range=10.0.0.2,10.0.0.255,12hPort Forwarding
In /etc/sysctl.conf, uncomment net.ipv4.ip_forward=1.
sudo iptables -t nat -A POSTROUTING -o wlan1 -j MASQUERADE
sudo iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
sudo iptables -A FORWARD -i wlan0 -o wlan1 -j ACCEPT
sudo sh -c 'iptables-save > /etc/iptables/rules.v4'Start services sudo service hostapd start && sudo service dnsmasq start. Reboot Raspberry Pi and test if attwifi can be connected to the internet.
Systemd Service and Timer
I use systemd to run my homepass.sh at boot time and the script will rerun every 5 minutes to change wlan0 to new SSID and MAC.
#/etc/systemd/system/homepass.service
[Unit]
Description=Homepass
[Service]
ExecStart=/home/pi/homepass.sh
[Install]
WantedBy=multi-user.target#/etc/systemd/system/homepass.timer
[Unit]
Description=Run homepass.service every 5 minutes
[Timer]
OnStartupSec=10
OnUnitActiveSec=5min
Unit=homepass.service
[Install]
WantedBy=multi-user.targetEnable the timer by executing this command
systemctl enable homepass.timer
systemctl start homepass.timerA nice feature of using systemd to run the script is we can access the logging easily for debugging
journalctl -u homepasshomepass.sh
This script was modified from orginal script by Semperverus. You can check out his guide for more details about HomePass. I took the idea of using sqlite3 to store MAC and SSID in a database from danielhoherd’s script.
The script is rerun every 5 minutes by systemd. It stops current running hostapd service. A new /etc/hostapd/hostapd.conf is generated from querying MAC and SSID from a database. The hostapd service is then restarted with the new conf file.
#!/bin/bash
service hostapd stop
SLEEP_TIME=300
DB=/home/pi/homepass.db
CONFIG_FILE=/etc/hostapd/hostapd.conf
if [[ ! -e "$CONFIG_FILE" ]] ; then
touch "$CONFIG_FILE"
fi
read -d '' query << EOF
SELECT mac, ssid
FROM aps
WHERE last_used < datetime('now', '-2 days') OR last_used IS NULL
ORDER BY random()
LIMIT 1;
EOF
result=$(sqlite3 "$DB" "$query")
resultArr=(${result//|/ })
MAC=${resultArr[0]}
SSID=${resultArr[1]}
if [[ -z "$MAC" ]] || [[ -z "$SSID" ]] ; then
echo "missing MAC or SSID"
exit 1
fi
sqlite3 "$DB" "UPDATE aps SET last_used = datetime('now') WHERE mac = '$MAC'"
cat > $CONFIG_FILE << EOF
ssid=$SSID
bssid=$MAC
interface=wlan0
driver=nl80211
hw_mode=g
channel=6
auth_algs=3
wpa=0
rsn_pairwise=CCMP
beacon_int=100
macaddr_acl=0
wmm_enabled=0
eap_reauth_period=360000000
EOF
echo "==========================================="
echo "SSID:" $SSID "- BSSID:" $MAC
echo "Time before next change:" $SLEEP_TIME "seconds"
echo "Current time:" $(date)
echo "==========================================="
service hostapd startAll Files
You can find all my files at my github repo.