Module: PWN::SDR::Decoder::RTL433

Defined in:
lib/pwn/sdr/decoder/rtl433.rb

Overview

Pure-Ruby ISM/keyfob/sensor activity detector for the 315 / 390 / 433.92 / 868 / 915 MHz device zoo.

The upstream rtl_433 binary carries ~250 device-specific protocol dissectors; re-implementing that library is out of scope. This module instead characterises OOK/ASK/FSK bursts natively (count, duration, gap, peak dBFS) — enough to fingerprint a keyfob press, a periodic weather-station beacon, or a TPMS chirp — without invoking any external binary. parse_line still accepts rtl_433 -F json output for offline analysis.

Class Method Summary collapse

Class Method Details

.authorsObject

Author(s)

0day Inc. support@0dayinc.com



66
67
68
# File 'lib/pwn/sdr/decoder/rtl433.rb', line 66

public_class_method def self.authors
  "AUTHOR(S):\n  0day Inc. <support@0dayinc.com>\n"
end

.decode(opts = {}) ⇒ Object

Supported Method Parameters

PWN::SDR::Decoder::RTL433.decode( freq_obj: 'required - freq_obj returned from PWN::SDR::GQRX.init_freq' )



24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
# File 'lib/pwn/sdr/decoder/rtl433.rb', line 24

public_class_method def self.decode(opts = {})
  freq_obj = opts[:freq_obj]
  PWN::SDR::Decoder::Base.run_detector(
    freq_obj: freq_obj,
    protocol: 'ISM-433',
    note: 'Native OOK/FSK burst characteriser (no rtl_433 binary). Feed captured `rtl_433 -F json` lines to .parse_line for per-device decode.',
    threshold: 10.0,
    describe: proc { |b|
      kind = if b[:duration_ms] < 20 then 'keyfob/OOK-short'
             elsif b[:duration_ms] < 120 then 'sensor/OOK-packet'
             else 'FSK-continuous'
             end
      { modulation: 'OOK/ASK/FSK', classification: kind }
    }
  )
end

.helpObject

Display Usage for this Module



72
73
74
75
76
77
78
79
80
81
82
# File 'lib/pwn/sdr/decoder/rtl433.rb', line 72

public_class_method def self.help
  puts "USAGE (ruby-native detector, no external binaries):
    #{self}.decode(
      freq_obj: 'required - freq_obj returned from PWN::SDR::GQRX.init_freq'
    )

    #{self}.parse_line(line: '{\"model\":\"Acurite-Tower\",\"id\":1234,...}')

    #{self}.authors
  "
end

.parse_line(opts = {}) ⇒ Object

Supported Method Parameters

PWN::SDR::Decoder::RTL433.parse_line(line: '"time":"...","model":".."time":"...","model":"..."')



44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
# File 'lib/pwn/sdr/decoder/rtl433.rb', line 44

public_class_method def self.parse_line(opts = {})
  line = opts[:line].to_s
  h = begin
    JSON.parse(line, symbolize_names: true)
  rescue StandardError
    { unparsed: line }
  end
  out = { protocol: 'RTL433' }.merge(h)
  bits = []
  bits << out[:model].to_s if out[:model]
  bits << "id=#{out[:id]}" if out[:id]
  bits << "ch=#{out[:channel]}" if out[:channel]
  bits << "code=#{out[:code]}" if out[:code]
  bits << "cmd=#{out[:cmd] || out[:button]}" if out[:cmd] || out[:button]
  bits << "temp=#{out[:temperature_C]}C" if out[:temperature_C]
  bits << "rssi=#{out[:rssi]}" if out[:rssi]
  out[:summary] = bits.empty? ? line[0, 120] : bits.join(' ')
  out
end