InfraFi

Transmit WiFi credentials from a Flipper Zero to a Linux server using infrared. Point, press Send, connected.

Built for headless servers (NAS boxes, Intel NUCs, etc.) where typing WiFi passwords is painful or impossible.

How It Works

flowchart LR
    subgraph Flipper Zero
        A[InfraFi App]
        A1[Manual Entry]
        A2[NFC Tag Scan]
        A3[Saved Networks]
        A1 --> A
        A2 --> A
        A3 --> A
    end

    subgraph Linux Server
        B[infrafid daemon]
        B1["IR RX (LIRC or evdev)"]
        B2[WiFi Connect]
        B3["IR TX (ACK)"]
        B1 --> B --> B2
        B -.-> B3
    end

    A -- "IR (RC-6 or NEC)" --> B1
    B3 -. "ACK (OK/FAIL)" .-> A

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The Flipper encodes WiFi credentials as a sequence of IR messages (RC-6 or NEC) and blasts them at the server's IR receiver. The infrafid daemon decodes the transmission and connects to the network automatically. No pairing, no Bluetooth, no network required — just line-of-sight IR.

With ACK enabled, the daemon transmits a response back via IR — the Flipper displays whether the connection succeeded (with IP address) or failed.

Features

Flipper Zero App

• Manual entry — On-screen keyboard for SSID and password, security type selector (Open/WPA/WEP/SAE)
• NFC WiFi tags — Scan an NTAG213/215/216 tag with WiFi credentials (standard NDEF WiFi Simple Configuration format) and transmit instantly
• Saved networks — Credentials auto-save to SD card after successful transmit. Browse, resend, or delete saved networks
• IR protocol selection — Choose between RC-6 (36kHz, for CIR receivers like ITE8708) or NEC (38kHz, for devices like the Squeezebox Touch) in Settings
• Fast transmission — Full credentials sent in under a second via RC-6, or a few seconds via NEC
• Hidden network support — Toggle hidden SSID flag
• ACK feedback — Optional. When enabled in Settings, the Flipper waits for a response from the server after sending credentials. Shows "Connected! IP: x.x.x.x" or "Failed" on screen

Linux Daemon (infrafid)

• Zero dependencies — Pure C, no Python or runtime libraries needed
• Automatic WiFi connection — Detects NetworkManager, systemd-networkd, or ifupdown and connects appropriately
• Rollback on failure — Saves current SSID before connecting; reconnects to previous network if the new one fails
• SSID verification — After WPA handshake completes, verifies the connected SSID matches the target to avoid false positives
• IR ACK response — Sends connection result back to the Flipper via IR (requires TX hardware or external IR blaster)
• Runs as a service — systemd unit with auto-restart, logs to journald/syslog
• Dual protocol — LIRC input accepts both RC-6 and NEC scancodes automatically (just enable the protocol in /sys/class/rc/rc*/protocols)
• ITE8708 optimized — Uses LIRC_MODE_SCANCODE for kernel-decoded scancodes, avoiding hardware FIFO overflow issues with the CIR receivers found in Intel NUCs
• evdev fallback — For devices without LIRC (e.g., Squeezebox Touch), read NEC scancodes from /dev/input/eventN via --evdev (expects FAB4-style bit ordering)

Getting Started

Requirements

Flipper Zero:

• Flipper Zero with up-to-date firmware
• ufbt (Flipper build tool)

Linux Server:

• IR receiver — tested with:
  • ITE8708 CIR in Intel NUCs (/dev/lirc0, RC-6 or NEC via LIRC)
  • Squeezebox Touch FAB4 IR (/dev/input/event1, NEC via evdev)
• gcc and Linux headers for building
• NetworkManager, systemd-networkd, or ifupdown + wpa_supplicant for WiFi management

Build & Install — Flipper App

# Clone the repo
git clone https://github.com/amd989/infrafi.git
cd infrafi

# Build
ufbt

# Deploy to Flipper (connected via USB)
ufbt launch

Build & Install — Linux Daemon

cd daemon

# Quick install (builds, installs, configures RC-6, starts service)
sudo ./install.sh

# Or manually:
make
sudo make install
sudo systemctl enable --now infrafid

The install script automatically:

• Configures the IR receiver for RC-6 and NEC protocols
• Creates a udev rule so the config persists across reboots
• Installs and starts the systemd service

Pre-built Packages

Debian/Ubuntu and RPM packages are available from GitHub Releases for amd64, arm64, armhf, and armel (ARMv6, Raspberry Pi Zero/1) architectures.

APT repository:

curl -fsSL https://amd989.github.io/InfraFi/install-apt.sh | sudo bash
sudo apt install infrafid

YUM repository:

curl -fsSL https://amd989.github.io/InfraFi/install-yum.sh | sudo bash
sudo yum install infrafid

Verify IR Receiver

# Check that rc-6 is the active protocol
cat /sys/class/rc/rc0/protocols
# Should show: ... [rc-6] ...

# Test reception (Ctrl+C to stop)
ir-keytable -t -s rc0

Usage

Manual Entry

1. Open InfraFi on your Flipper
2. Select Send Credentials
3. Enter SSID, password, and security type
4. Review on the confirm screen, press Send
5. Point the Flipper at the server's IR receiver

NFC Tag

1. Write WiFi credentials to an NTAG213/215/216 using a phone app (e.g., NFC Tools)
2. Open InfraFi → Scan NFC Tag
3. Hold the tag to the back of the Flipper
4. Review credentials, press Send

Saved Networks

1. Previously transmitted networks are auto-saved to the SD card
2. Open InfraFi → Saved to browse them
3. Select a network to resend

IR Protocol

1. Open InfraFi → Settings → set IR Protocol to RC-6 (default) or NEC
2. Use RC-6 for CIR hardware designed for media center remotes (Intel NUCs)
3. Use NEC for devices with NEC-based IR receivers (Squeezebox Touch, many consumer devices)

Note: On the daemon side, LIRC accepts both RC-6 and NEC automatically — no flag changes needed, just ensure the protocol is enabled in /sys/class/rc/rc*/protocols. The --evdev flag is only needed for devices that don't have LIRC (like the Squeezebox Touch).

ACK (Bidirectional Feedback)

1. Open InfraFi → Settings → set Wait for ACK to On
2. Send credentials as usual
3. After transmitting, the Flipper shows "Waiting for server response..." with a cyan LED
4. The daemon connects to WiFi and transmits the result back via IR:
   • Connected! — green LED, shows IP address
   • Failed — red LED
   • No response — times out after 30 seconds (credentials were still sent)

Note: ACK requires an IR transmitter on the server side. Many NUCs have a CIR receiver but no TX LED. Use --ack-device with an external USB IR blaster if needed.

Daemon

# Run in foreground with verbose logging (useful for testing)
sudo infrafid -f -v

# Use an evdev device for NEC reception (e.g., Squeezebox Touch)
sudo infrafid -e /dev/input/event1 -f -v

# Use a separate IR device for ACK transmission
sudo infrafid -a /dev/lirc1

# LIRC RX on lirc0, ACK TX on lirc1
sudo infrafid -d /dev/lirc0 -a /dev/lirc1

# Check service status
sudo systemctl status infrafid

# Watch logs
sudo journalctl -u infrafid -f

Flag	Description
-d, --device PATH	LIRC device for RX (default: /dev/lirc0)
-e, --evdev PATH	evdev input device for RX (NEC via MSC_RAW, FAB4-style bit ordering)
-a, --ack-device PATH	LIRC device for ACK TX (default: same as -d)
-f, --foreground	Run in foreground (don't daemonize)
-v, --verbose	Verbose logging

Protocol

InfraFi supports two IR transport protocols. The framing and payload format are identical — only the physical IR encoding differs:

	RC-6 Mode 0	NEC
Carrier	36kHz	38kHz
Frame time	~25ms	~67ms
Daemon input	LIRC	LIRC or evdev
Typical hardware	ITE8708 CIR (Intel NUCs)	Squeezebox Touch (FAB4 IR), any NEC receiver
Flipper setting	RC-6 (default)	NEC

RC-6 is the default and recommended for CIR receivers — it's faster and uses the kernel's built-in decoder (LIRC_MODE_SCANCODE), avoiding the tiny hardware FIFO that overflows with custom raw protocols. NEC works through LIRC as well (enable nec in /sys/class/rc/rc*/protocols), or through the Linux input subsystem (--evdev) for devices without LIRC.

evdev note: The current evdev decoder assumes FAB4-style NEC byte bit-ordering and bit-reverses each byte before validation.

Each IR message carries one byte of payload:

Field	Bits	Description
Magic	addr[7:4]	0xA — identifies InfraFi messages
Frame type	addr[3:2]	00=START, 01=DATA, 10=END
Pass	addr[1:0]	Retransmission attempt (0-3)
Command	cmd[7:0]	Payload byte

Credentials (Flipper → daemon): START(len) → DATA × N → END(crc8)

Payload is a standard WiFi QR string: WIFI:T:WPA;S:MyNetwork;P:MyPassword;H:false;;

ACK (daemon → Flipper): Same framing. Payload is OK:192.168.1.102 on success or FAIL on failure.

Project Structure

infrafi/
├── application.fam              # Flipper app manifest
├── flipper/                     # Flipper Zero app
│   ├── wi_fir.h/c               # App entry, ViewDispatcher + SceneManager
│   ├── wfr_encode.h/c           # IR encoder + transmitter (RC-6 / NEC)
│   ├── wfr_decode.h/c           # ACK decoder (IR receive)
│   ├── wfr_nfc.h/c              # NFC NDEF WiFi tag parser
│   ├── wfr_storage.h/c          # SD card credential + settings storage
│   ├── protocol/
│   │   ├── wfr_protocol.h       # Shared protocol constants + structs
│   │   ├── wfr_protocol.c       # CRC-8, WiFi string builder/parser
│   │   └── version.h            # Shared version (Flipper + daemon)
│   ├── scenes/                  # UI scenes (menu, editors, confirm, transmit, NFC, saved, settings, about)
│   └── images/                  # App icon
├── daemon/                      # Linux daemon (infrafid)
│   ├── main.c                   # Entry point, CLI args, main loop
│   ├── wfr_lirc.h/c             # LIRC scancode reader (RC-6 / NEC)
│   ├── wfr_evdev.h/c            # evdev input reader (NEC via MSC_RAW)
│   ├── wfr_decode.h/c           # IR message reassembler
│   ├── wfr_network.h/c          # WiFi connector (NM/networkd/ifupdown) with rollback
│   ├── wfr_ack.h/c              # IR ACK transmitter (LIRC TX)
│   ├── Makefile                 # Build
│   ├── infrafid.service         # systemd unit
│   └── install.sh               # One-step install
├── debian/                      # Debian packaging
├── rpm/                         # RPM packaging
└── .github/workflows/           # CI/CD (ci.yml, release.yml)

Author

Alejandro Mora — github.com/amd989

License

MIT