Merge pull request freifunk-gluon#138 from freifunk-gluon/improve_ssid_changer

ffac-ssid-changer: rewrite in lua, use wifi reconf

Author: maurerle

ffac-ssid-changer/Makefile

@@ -24,18 +24,4 @@ define Package/$(PKG_NAME)/description
   most.
 endef
 
-
-define Build/Compile
-	$(call Gluon/Build/Compile)
-	./gluonShellDiet.sh shsrc/ssid-changer.sh > $(PKG_BUILD_DIR)/ssid-changer.sh
-endef
-
-define Package/$(PKG_NAME)/install
-	$(Gluon/Build/Install)
-
-	$(INSTALL_DIR) $(1)/lib/gluon/ssid-changer
-	$(INSTALL_BIN) $(PKG_BUILD_DIR)/ssid-changer.sh $(1)/lib/gluon/ssid-changer/
-endef
-
-
 $(eval $(call BuildPackageGluon,$(PKG_NAME)))

ffac-ssid-changer/files/usr/lib/micron.d/ssid-changer

@@ -1 +1 @@
-* * * * * /lib/gluon/ssid-changer/ssid-changer.sh
+* * * * * /lib/gluon/ssid-changer/ssid-changer.lua

ffac-ssid-changer/gluonShellDiet.sh

@@ -0,0 +1,227 @@
+#!/usr/bin/lua
+
+local uci = require('simple-uci').cursor()
+
+-- Safety check functions
+local function log_debug(...)
+    if uci:get('ssid-changer', 'settings', 'debug_log_enabled') == '1' then
+        os.execute('logger -t "ffac-ssid-changer" -p debug "' .. table.concat({...}, ' ') .. '"')
+    end
+end
+
+local function log(...)
+    os.execute('logger -t "ffac-ssid-changer" "' .. table.concat({...}, ' ') .. '"')
+end
+
+local function safety_exit(message)
+    log_debug(message .. ", exiting with error code 2")
+    os.exit(2)
+end
+
+-- Check if the script is enabled
+if uci:get('ssid-changer', 'settings', 'enabled') == '0' then
+    os.exit(0)  -- Exit silently if the script is disabled
+end
+
+-- Check for autoupdater running
+local function is_autoupdater_running()
+    local handle = io.popen('pgrep -f autoupdater')
+    local result = handle:read("*a")
+    handle:close()
+    return result ~= ''
+end
+
+if is_autoupdater_running() then
+    safety_exit('autoupdater running')
+end
+
+-- Read uptime
+local function get_uptime()
+    local file = io.open('/proc/uptime', 'r')
+    local uptime = file:read("*n")  -- Read only the first number (uptime in seconds)
+    file:close()
+    return uptime
+end
+
+local uptime = get_uptime()
+local uptime_minutes = math.floor(uptime / 60)
+local monitor_duration = tonumber(uci:get('ssid-changer', 'settings', 'switch_timeframe') or 30)
+local is_switch_time = uptime_minutes % monitor_duration
+
+if uptime < 60 then
+    safety_exit('uptime less than one minute')
+end
+
+-- Check for hostapd processes
+local function has_hostapd_processes()
+    local handle = io.popen('find /var/run -name "hostapd-*.conf" | wc -l')
+    local result = handle:read("*a")
+    handle:close()
+    return tonumber(result) > 0
+end
+
+if not has_hostapd_processes() then
+    safety_exit('no hostapd-*')
+end
+
+-- Generate the offline SSID
+local function calculate_offline_ssid()
+    local prefix = uci:get('ssid-changer', 'settings', 'prefix') or 'FF_Offline_'
+    local settings_suffix = uci:get('ssid-changer', 'settings', 'suffix') or 'nodename'
+    local suffix
+
+    if settings_suffix == 'nodename' then
+        suffix = io.popen('uname -n'):read("*a"):gsub("%s+", "")
+        if #suffix > (30 - #prefix) then
+            local max_suffix_length = math.floor((28 - #prefix) / 2)
+            local suffix_first_chars = suffix:sub(1, max_suffix_length)
+            local suffix_last_chars = suffix:sub(-max_suffix_length)
+            suffix = suffix_first_chars .. '...' .. suffix_last_chars
+        end
+    elseif settings_suffix == 'mac' then
+        suffix = io.popen('uci -q get network.bat0.macaddr | sed "s/://g"'):read("*a"):gsub("%s+", "")
+    else
+        suffix = ''
+    end
+
+    return prefix .. suffix
+end
+
+local offline_ssid = calculate_offline_ssid()
+
+-- Count offline incidents
+local tmp = '/tmp/ssid-changer-count'
+local tmp_state = '/tmp/ssid-changer-offline'
+local off_count = 0
+local file = io.open(tmp, 'r')
+
+local is_offline = 0
+local state_file = io.open(tmp_state, 'r')
+
+if state_file then
+    is_offline = tonumber(state_file:read("*a")) or 0
+    state_file:close()
+else
+    state_file = io.open(tmp_state, 'w')
+    state_file:write("0")
+    state_file:close()
+end
+
+if file then
+    off_count = tonumber(file:read("*a")) or 0
+    file:close()
+else
+    file = io.open(tmp, 'w')
+    file:write("0")
+    file:close()
+end
+
+local function calculate_tq_limit()
+    local tq_limit_max = tonumber(uci:get('ssid-changer', 'settings', 'tq_limit_max') or 45)
+    local tq_limit_min = tonumber(uci:get('ssid-changer', 'settings', 'tq_limit_min') or 35)
+    local gateway_tq
+
+    local handle = io.popen('batctl gwl -H | grep -e "^\\*" | awk -F"[()]" "{print $2}" | tr -d " "')
+    gateway_tq = tonumber(handle:read("*a"))
+    handle:close()
+
+    if not gateway_tq then
+        safety_exit('tq_limit can not be calculated without gateway')
+    end
+    local is_online
+
+    if gateway_tq >= tq_limit_max then
+        is_online = true
+    elseif gateway_tq < tq_limit_min then
+        is_online = false
+    else
+        -- in the middle part we consider us offline if there was at least one offline incidents
+        -- or we were offline before the current monitor interval
+        is_online = off_count > 0
+    end
+
+    if is_online then
+        return 'online'
+    else
+        return 'offline'
+    end
+end
+
+local function has_default_gw4()
+    local default_gw4 = io.open('/var/gluon/state/has_default_gw4', 'r')
+    if default_gw4 then
+        default_gw4:close()
+        return true
+    end
+    return false
+end
+
+local status
+if has_default_gw4() then
+    local tq_limit_enabled = tonumber(uci:get('ssid-changer', 'settings', 'tq_limit_enabled') or 0)
+
+    if tq_limit_enabled == 1 then
+        status = calculate_tq_limit()
+    else
+        status = 'online'
+    end
+else
+    status = 'offline'
+end
+
+if status == 'online' then
+    log_debug("node is online")
+    -- only revert and reconf if we were offline in the current monitoring timeframe or before
+    -- to reduce impact
+    if off_count > 0 then
+        log("reverting offline ssid back to default wireless config")
+        uci:revert('wireless')
+        os.execute('wifi reconf')
+    end
+elseif status == 'offline' then
+    log_debug("node is considered offline")
+    local first = tonumber(uci:get('ssid-changer', 'settings', 'first') or 5)
+    -- set SSID offline, only if uptime is less than FIRST or exactly a multiplicative of switch_timeframe
+    if uptime_minutes < first or is_switch_time == 0 then
+
+        -- check if off_count is more than half of the monitor duration
+        if not is_offline and off_count >= math.floor(monitor_duration / 2) then
+            -- if has been offline for at least half checks in monitor duration
+            -- set the SSID to the offline SSID
+            -- and disable owe client radios
+            for i = 0, 2 do
+                local client_ssid = uci:get('wireless', 'client_radio' .. i, 'ssid')
+                if client_ssid then
+                    uci:set('wireless', 'client_radio' .. i, 'ssid', offline_ssid)
+                end
+
+                local owe_ssid = uci:get('wireless', 'owe_radio' .. i, 'ssid')
+                if owe_ssid then
+                    uci:set('wireless', 'owe_radio' .. i, 'disabled', 1)
+                end
+                -- save does not commit
+                uci:save('wireless')
+            end
+            log("reconfiguring wifi to offline ssid")
+            os.execute('wifi reconf')
+        end
+    end
+    off_count = off_count + 1
+    file = io.open(tmp, 'w')
+    file:write(tostring(off_count))
+    file:close()
+end
+
+if is_switch_time == 0 then
+    file = io.open(tmp, 'w')
+    state_file = io.open(tmp_state, 'w')
+
+    if status == 'offline' then
+        file:write("1")
+        state_file:write("1")
+    else
+        file:write("0")
+        state_file:write("0")
+    end
+    file:close()
+end