print("WiFi RSSI Analyzer")

local macaddress_ssid = {}
local macaddress_resolved = {}
local rssi_ap = {}
local rssi_other = {}
local ssid_other = {}

local field_radiotap_dbm_antsignal = Field.new("radiotap.dbm_antsignal")
local field_radiotap_channel_freq = Field.new("radiotap.channel.freq")
local field_radiotap_flags_badfcs = Field.new("radiotap.flags.badfcs")
local field_wlan_mgt_ssid = Field.new("wlan_mgt.ssid")
local field_wlan_fc_type_subtype = Field.new("wlan.fc.type_subtype")
local field_wlan_sa = Field.new("wlan.sa")                   -- Source Address
local field_wlan_ta = Field.new("wlan.ta")                   -- Transmitter Address (can be WiFi Access Point)
local field_wlan_ta_resolved = Field.new("wlan.ta_resolved") -- Transmitter Address (can be WiFi Access Point)
local field_wlan_ra = Field.new("wlan.ra")                   -- Receiver Address (can be WiFi Access Point)
local field_wlan_da = Field.new("wlan.da")                   -- Destination Address

local tap = Listener.new()
local count = 0
local subcount = 0
local maccount = 0
local ssidcount = 0
local ch_freq = 0

function tap.packet(pinfo,tvb)  -- Run for each captured packet.
  -- Get Field values --
  local radiotap_dbm_antsignal = field_radiotap_dbm_antsignal()
  local wlan_mgt_ssid = field_wlan_mgt_ssid()
  local wlan_fc_type_subtype = field_wlan_fc_type_subtype()
  local wlan_sa = field_wlan_sa()
  local wlan_ta = field_wlan_ta()
  local wlan_ta_resolved = field_wlan_ta_resolved()
  local wlan_ra = field_wlan_ra()
  local wlan_da = field_wlan_da()
  local radiotap_channel_freq = field_radiotap_channel_freq()

  if tostring(radiotap_channel_freq)~=nil then
    ch_freq = tonumber(tostring(radiotap_channel_freq))
  end
  
  if tostring(radiotap_flags_badfcs)~=nil then
    if tostring(radiotap_flags_badfcs)~="0" then
      print("Bad FCS.")
      return
    end
  end

  if tonumber(tostring(wlan_fc_type_subtype))~=nil and tostring(radiotap_dbm_antsignal)~=nil then
--[[
    print("******START******")
    print(tostring(radiotap_dbm_antsignal))
    print(tostring(wlan_mgt_ssid))
    print(tostring(wlan_fc_type_subtype))
    print("wlan_sa " .. tostring(wlan_sa))
    print("wlan_ta " .. tostring(wlan_ta))
    print("wlan_ta_resolved " .. tostring(wlan_ta_resolved))
    print("wlan_ra " .. tostring(wlan_ra))
    print("wlan_da " .. tostring(wlan_da))
    print("*******END*******")
]]
    if tostring(wlan_fc_type_subtype)=="8" or tostring(wlan_fc_type_subtype)=="5" then
    -- Signal Strength vs Access Point --
      if wlan_ta~=nil then
        rssi_ap[tostring(wlan_ta)]=tostring(radiotap_dbm_antsignal)
        if wlan_mgt_ssid~=nil then
          macaddress_ssid[tostring(wlan_ta)]=tostring(wlan_mgt_ssid)
        else
          macaddress_ssid[tostring(wlan_ta)]=tostring(wlan_ta)
        end
        if wlan_ta_resolved~=nil then
          macaddress_resolved[tostring(wlan_ta)]=tostring(wlan_ta_resolved)
        end
      end
    else
    -- Connected Access Point vs Terminal MAC address --
      if tonumber(tostring(wlan_fc_type_subtype))>16 then  -- Access after Association
        local igbit = tonumber(string.sub(tostring(wlan_ra),2,2))
        if macaddress_ssid[tostring(wlan_ta)] and tostring(wlan_ra)~=nil and igbit~=nil then
          if igbit%2 == 0 and rssi_other[tostring(wlan_ra)]~=nil then -- Not Multicast MAC Address
            ssid_other[tostring(wlan_ra)]=macaddress_ssid[tostring(wlan_ta)]
          end
        end
      end
    -- Signal Strength vs Terminal MAC address --
      if wlan_ta~=nil then
        rssi_other[tostring(wlan_ta)]=tostring(radiotap_dbm_antsignal)
        if wlan_ta_resolved~=nil then
          macaddress_resolved[tostring(wlan_ta)]=tostring(wlan_ta_resolved)
        end
      end
    end
  end
  count=count+1
  subcount=subcount+1
  if subcount>=100 then
    maccount = 0;
    ssidcount = 0;
    for macadrs,rssi in pairs(rssi_other) do
      maccount = maccount + 1
    end
    for macadrs,ssid in pairs(ssid_other) do
      ssidcount = ssidcount + 1
    end
        print(tostring(count) .. " packets.\t" .. tostring(maccount) .. " Terminals. (" .. tostring(ssidcount) .. " AP info)")
    subcount=0
  end
end

function tap.draw(t)
  for macadrs,rssi in pairs(rssi_ap) do
    if macaddress_ssid[macadrs] and macaddress_resolved[macadrs] then
      print(tostring(ch_freq) .. ",AP," .. macadrs .. "," .. rssi .. "," .. macaddress_resolved[macadrs] .. "," .. macaddress_ssid[macadrs])
    elseif macaddress_resolved[macadrs] then
      print(tostring(ch_freq) .. ",AP," .. macadrs .. "," .. rssi .. "," .. macaddress_resolved[macadrs])
    elseif macaddress_ssid[macadrs] then
      print(tostring(ch_freq) .. ",AP," .. macadrs .. "," .. rssi .. "," .. macadrs .. "," .. macaddress_ssid[macadrs])
    else
      print(tostring(ch_freq) .. ",AP," .. macadrs .. "," .. rssi .. "," .. macadrs)
    end
  end
  for macadrs,rssi in pairs(rssi_other) do
    if macaddress_ssid[macadrs]==nil then
      if macaddress_resolved[macadrs] and ssid_other[macadrs] then
        print(tostring(ch_freq) .. ",Terminal," .. macadrs .. "," .. rssi .. "," .. macaddress_resolved[macadrs] .. "," .. ssid_other[macadrs] )
      elseif macaddress_resolved[macadrs] then
        print(tostring(ch_freq) .. ",Terminal," .. macadrs .. "," .. rssi .. "," .. macaddress_resolved[macadrs] )
      elseif ssid_other[macadrs] then
        print(tostring(ch_freq) .. ",Terminal," .. macadrs .. "," .. rssi .. "," .. macadrs .. "," .. ssid_other[macadrs] )
      end
    end
  end
end