#308 integrated new settings file with supervisor

coordinator/iocontrol.lua

@@ -110,9 +110,9 @@ function iocontrol.init(conf, comms)
     -- determine tank information
     if io.facility.tank_mode == 0 then
         io.facility.tank_defs = {}
-        -- on facility tank mode 0, setup tank defs to match unit TANK option
+        -- on facility tank mode 0, setup tank defs to match unit tank option
         for i = 1, conf.num_units do
-            io.facility.tank_defs[i] = util.trinary(conf.cooling.r_cool[i].TANK, 1, 0)
+            io.facility.tank_defs[i] = util.trinary(conf.cooling.r_cool[i].TankConnection, 1, 0)
         end
 
         io.facility.tank_list = { table.unpack(io.facility.tank_defs) }
@@ -214,7 +214,7 @@ function iocontrol.init(conf, comms)
             num_boilers = 0,
             num_turbines = 0,
             num_snas = 0,
-            has_tank = conf.cooling.r_cool[i].TANK,
+            has_tank = conf.cooling.r_cool[i].TankConnection,
 
             control_state = false,
             burn_rate_cmd = 0.0,
@@ -295,13 +295,13 @@ function iocontrol.init(conf, comms)
         end
 
         -- create boiler tables
-        for _ = 1, conf.cooling.r_cool[i].BOILERS do
+        for _ = 1, conf.cooling.r_cool[i].BoilerCount do
             table.insert(entry.boiler_ps_tbl, psil.create())
             table.insert(entry.boiler_data_tbl, {})
         end
 
         -- create turbine tables
-        for _ = 1, conf.cooling.r_cool[i].TURBINES do
+        for _ = 1, conf.cooling.r_cool[i].TurbineCount do
             table.insert(entry.turbine_ps_tbl, psil.create())
             table.insert(entry.turbine_data_tbl, {})
         end

coordinator/startup.lua

@@ -22,7 +22,7 @@ local sounder     = require("coordinator.sounder")
 
 local apisessions = require("coordinator.session.apisessions")
 
-local COORDINATOR_VERSION = "v1.0.18"
+local COORDINATOR_VERSION = "v1.1.0"
 
 local println = util.println
 local println_ts = util.println_ts

supervisor/configure.lua

@@ -96,17 +96,17 @@ local tmp_cfg = {
     CoolingConfig = {},
     FacilityTankMode = 0,
     FacilityTankDefs = {},
-    SVR_Channel = nil,
+    SVR_Channel = nil,  ---@type integer
-    PLC_Channel = nil,
+    PLC_Channel = nil,  ---@type integer
-    RTU_Channel = nil,
+    RTU_Channel = nil,  ---@type integer
-    CRD_Channel = nil,
+    CRD_Channel = nil,  ---@type integer
-    PKT_Channel = nil,
+    PKT_Channel = nil,  ---@type integer
-    PLC_Timeout = nil,
+    PLC_Timeout = nil,  ---@type number
-    RTU_Timeout = nil,
+    RTU_Timeout = nil,  ---@type number
-    CRD_Timeout = nil,
+    CRD_Timeout = nil,  ---@type number
-    PKT_Timeout = nil,
+    PKT_Timeout = nil,  ---@type number
-    TrustedRange = nil,
+    TrustedRange = nil, ---@type number
-    AuthKey = nil,
+    AuthKey = nil,      ---@type string|nil
     LogMode = 0,
     LogPath = "",
     LogDebug = false,

supervisor/facility.lua

@@ -135,7 +135,7 @@ function facility.new(num_reactors, cooling_conf)
 
     -- create units
     for i = 1, num_reactors do
-        table.insert(self.units, unit.new(i, cooling_conf.r_cool[i].BOILERS, cooling_conf.r_cool[i].TURBINES))
+        table.insert(self.units, unit.new(i, cooling_conf.r_cool[i].BoilerCount, cooling_conf.r_cool[i].TurbineCount))
         table.insert(self.group_map, 0)
     end
 

supervisor/session/svsessions.lua

@@ -2,16 +2,14 @@ local log         = require("scada-common.log")
 local mqueue      = require("scada-common.mqueue")
 local util        = require("scada-common.util")
 
-local config      = require("supervisor.config")
 local databus     = require("supervisor.databus")
 local facility    = require("supervisor.facility")
 
-local svqtypes    = require("supervisor.session.svqtypes")
-
 local coordinator = require("supervisor.session.coordinator")
 local plc         = require("supervisor.session.plc")
 local pocket      = require("supervisor.session.pocket")
 local rtu         = require("supervisor.session.rtu")
+local svqtypes    = require("supervisor.session.svqtypes")
 
 -- Supervisor Sessions Handler
 
@@ -36,6 +34,7 @@ svsessions.SESSION_TYPE = SESSION_TYPE
 local self = {
     nic = nil,          ---@type nic|nil
     fp_ok = false,
+    config = nil,       ---@type svr_config
     num_reactors = 0,
     facility = nil,     ---@type facility|nil
     sessions = { rtu = {}, plc = {}, crd = {}, pdg = {} },
@@ -60,7 +59,7 @@ local function _sv_handle_outq(session)
         if msg ~= nil then
             if msg.qtype == mqueue.TYPE.PACKET then
                 -- handle a packet to be sent
-                self.nic.transmit(session.r_chan, config.SVR_CHANNEL, msg.message)
+                self.nic.transmit(session.r_chan, self.config.SVR_Channel, msg.message)
             elseif msg.qtype == mqueue.TYPE.COMMAND then
                 -- handle instruction/notification
             elseif msg.qtype == mqueue.TYPE.DATA then
@@ -135,7 +134,7 @@ local function _shutdown(session)
     while session.out_queue.ready() do
         local msg = session.out_queue.pop()
         if msg ~= nil and msg.qtype == mqueue.TYPE.PACKET then
-            self.nic.transmit(session.r_chan, config.SVR_CHANNEL, msg.message)
+            self.nic.transmit(session.r_chan, self.config.SVR_Channel, msg.message)
         end
     end
 
@@ -197,13 +196,13 @@ end
 -- initialize svsessions
 ---@param nic nic network interface device
 ---@param fp_ok boolean front panel active
----@param num_reactors integer number of reactors
+---@param config svr_config supervisor configuration
 ---@param cooling_conf sv_cooling_conf cooling configuration definition
-function svsessions.init(nic, fp_ok, num_reactors, cooling_conf)
+function svsessions.init(nic, fp_ok, config, cooling_conf)
     self.nic = nic
     self.fp_ok = fp_ok
-    self.num_reactors = num_reactors
+    self.config = config
-    self.facility = facility.new(num_reactors, cooling_conf)
+    self.facility = facility.new(config.UnitCount, cooling_conf)
 end
 
 -- find an RTU session by the computer ID
@@ -287,7 +286,7 @@ function svsessions.establish_plc_session(source_addr, for_reactor, version)
             open = true,
             reactor = for_reactor,
             version = version,
-            r_chan = config.PLC_CHANNEL,
+            r_chan = self.config.PLC_Channel,
             s_addr = source_addr,
             in_queue = mqueue.new(),
             out_queue = mqueue.new(),
@@ -296,8 +295,7 @@ function svsessions.establish_plc_session(source_addr, for_reactor, version)
 
         local id = self.next_ids.plc
 
-        plc_s.instance = plc.new_session(id, source_addr, for_reactor, plc_s.in_queue, plc_s.out_queue,
+        plc_s.instance = plc.new_session(id, source_addr, for_reactor, plc_s.in_queue, plc_s.out_queue, self.config.PLC_Timeout, self.fp_ok)
-                                            config.PLC_TIMEOUT, self.fp_ok)
         table.insert(self.sessions.plc, plc_s)
 
         local units = self.facility.get_units()
@@ -305,8 +303,7 @@ function svsessions.establish_plc_session(source_addr, for_reactor, version)
 
         local mt = {
             ---@param s plc_session_struct
-            __tostring = function (s)  return util.c("PLC [", s.instance.get_id(), "] for reactor #", s.reactor,
+            __tostring = function (s)  return util.c("PLC [", s.instance.get_id(), "] for reactor #", s.reactor, " (@", s.s_addr, ")") end
-                                                        " (@", s.s_addr, ")") end
         }
 
         setmetatable(plc_s, mt)
@@ -336,7 +333,7 @@ function svsessions.establish_rtu_session(source_addr, advertisement, version)
         s_type = "rtu",
         open = true,
         version = version,
-        r_chan = config.RTU_CHANNEL,
+        r_chan = self.config.RTU_Channel,
         s_addr = source_addr,
         in_queue = mqueue.new(),
         out_queue = mqueue.new(),
@@ -345,8 +342,7 @@ function svsessions.establish_rtu_session(source_addr, advertisement, version)
 
     local id = self.next_ids.rtu
 
-    rtu_s.instance = rtu.new_session(id, source_addr, rtu_s.in_queue, rtu_s.out_queue, config.RTU_TIMEOUT,
+    rtu_s.instance = rtu.new_session(id, source_addr, rtu_s.in_queue, rtu_s.out_queue, self.config.RTU_Timeout, advertisement, self.facility, self.fp_ok)
-                                        advertisement, self.facility, self.fp_ok)
     table.insert(self.sessions.rtu, rtu_s)
 
     local mt = {
@@ -377,7 +373,7 @@ function svsessions.establish_crd_session(source_addr, version)
             s_type = "crd",
             open = true,
             version = version,
-            r_chan = config.CRD_CHANNEL,
+            r_chan = self.config.CRD_Channel,
             s_addr = source_addr,
             in_queue = mqueue.new(),
             out_queue = mqueue.new(),
@@ -386,8 +382,7 @@ function svsessions.establish_crd_session(source_addr, version)
 
         local id = self.next_ids.crd
 
-        crd_s.instance = coordinator.new_session(id, source_addr, crd_s.in_queue, crd_s.out_queue, config.CRD_TIMEOUT,
+        crd_s.instance = coordinator.new_session(id, source_addr, crd_s.in_queue, crd_s.out_queue, self.config.CRD_Timeout, self.facility, self.fp_ok)
-                                                    self.facility, self.fp_ok)
         table.insert(self.sessions.crd, crd_s)
 
         local mt = {
@@ -421,7 +416,7 @@ function svsessions.establish_pdg_session(source_addr, version)
         s_type = "pkt",
         open = true,
         version = version,
-        r_chan = config.PKT_CHANNEL,
+        r_chan = self.config.PKT_Channel,
         s_addr = source_addr,
         in_queue = mqueue.new(),
         out_queue = mqueue.new(),
@@ -430,8 +425,7 @@ function svsessions.establish_pdg_session(source_addr, version)
 
     local id = self.next_ids.pdg
 
-    pdg_s.instance = pocket.new_session(id, source_addr, pdg_s.in_queue, pdg_s.out_queue, config.PKT_TIMEOUT, self.facility,
+    pdg_s.instance = pocket.new_session(id, source_addr, pdg_s.in_queue, pdg_s.out_queue, self.config.PKT_Timeout, self.facility, self.fp_ok)
-                                        self.fp_ok)
     table.insert(self.sessions.pdg, pdg_s)
 
     local mt = {

supervisor/startup.lua

@@ -14,70 +14,66 @@ local util       = require("scada-common.util")
 
 local core       = require("graphics.core")
 
-local config     = require("supervisor.config")
+local configure  = require("supervisor.configure")
 local databus    = require("supervisor.databus")
 local renderer   = require("supervisor.renderer")
 local supervisor = require("supervisor.supervisor")
 
 local svsessions = require("supervisor.session.svsessions")
 
-local SUPERVISOR_VERSION = "v1.1.0"
+local SUPERVISOR_VERSION = "v1.2.0"
 
 local println = util.println
 local println_ts = util.println_ts
 
 ----------------------------------------
--- config validation
+-- get configuration
 ----------------------------------------
 
+if not supervisor.load_config() then
+    -- try to reconfigure (user action)
+    local success, error = configure.configure(true)
+    if success then
+        assert(supervisor.load_config(), "failed to load valid supervisor configuration")
+    else
+        assert(success, "supervisor configuration error: " .. error)
+    end
+end
+
+local config = supervisor.config
+
 local cfv = util.new_validator()
 
-cfv.assert_channel(config.SVR_CHANNEL)
+assert((config.FacilityTankMode == 0) or (config.UnitCount == #config.FacilityTankDefs),
-cfv.assert_channel(config.PLC_CHANNEL)
+    "startup> FacilityTankDefs length not equal to UnitCount")
-cfv.assert_channel(config.RTU_CHANNEL)
-cfv.assert_channel(config.CRD_CHANNEL)
-cfv.assert_channel(config.PKT_CHANNEL)
-cfv.assert_type_int(config.TRUSTED_RANGE)
-cfv.assert_type_num(config.PLC_TIMEOUT)
-cfv.assert_min(config.PLC_TIMEOUT, 2)
-cfv.assert_type_num(config.RTU_TIMEOUT)
-cfv.assert_min(config.RTU_TIMEOUT, 2)
-cfv.assert_type_num(config.CRD_TIMEOUT)
-cfv.assert_min(config.CRD_TIMEOUT, 2)
-cfv.assert_type_num(config.PKT_TIMEOUT)
-cfv.assert_min(config.PKT_TIMEOUT, 2)
-cfv.assert_type_int(config.NUM_REACTORS)
-cfv.assert_type_table(config.REACTOR_COOLING)
-cfv.assert_type_int(config.FAC_TANK_MODE)
-cfv.assert_type_table(config.FAC_TANK_DEFS)
-cfv.assert_type_str(config.LOG_PATH)
-cfv.assert_type_int(config.LOG_MODE)
 
-assert(cfv.valid(), "bad config file: missing/invalid fields")
+for i = 1, config.UnitCount do
+    local def = config.FacilityTankDefs[i]
+    cfv.assert_type_int(def)
+    cfv.assert_range(def, 0, 2)
+    assert(cfv.valid(), "startup> invalid facility tank definition for reactor unit " .. i)
+end
 
-assert((config.FAC_TANK_MODE == 0) or (config.NUM_REACTORS == #config.FAC_TANK_DEFS),
+cfv.assert_eq(#config.CoolingConfig, config.UnitCount)
-    "bad config file: FAC_TANK_DEFS length not equal to NUM_REACTORS")
+assert(cfv.valid(), "startup> the number of reactor cooling configurations is different than the number of units")
 
-cfv.assert_eq(#config.REACTOR_COOLING, config.NUM_REACTORS)
+for i = 1, config.UnitCount do
-assert(cfv.valid(), "config: number of cooling configs different than number of units")
+    cfv.assert_type_table(config.CoolingConfig[i])
-
+    assert(cfv.valid(), "startup> missing cooling entry for reactor unit " .. i)
-for i = 1, config.NUM_REACTORS do
+    cfv.assert_type_int(config.CoolingConfig[i].BoilerCount)
-    cfv.assert_type_table(config.REACTOR_COOLING[i])
+    cfv.assert_type_int(config.CoolingConfig[i].TurbineCount)
-    assert(cfv.valid(), "config: missing cooling entry for reactor " .. i)
+    cfv.assert_type_bool(config.CoolingConfig[i].TankConnection)
-    cfv.assert_type_int(config.REACTOR_COOLING[i].BOILERS)
+    assert(cfv.valid(), "startup> missing boiler/turbine/tank fields for reactor unit " .. i)
-    cfv.assert_type_int(config.REACTOR_COOLING[i].TURBINES)
+    cfv.assert_range(config.CoolingConfig[i].BoilerCount, 0, 2)
-    cfv.assert_type_bool(config.REACTOR_COOLING[i].TANK)
+    cfv.assert_range(config.CoolingConfig[i].TurbineCount, 1, 3)
-    assert(cfv.valid(), "config: missing boilers/turbines for reactor " .. i)
+    assert(cfv.valid(), "startup> out-of-range number of boilers and/or turbines provided for reactor unit " .. i)
-    cfv.assert_min(config.REACTOR_COOLING[i].BOILERS, 0)
-    cfv.assert_min(config.REACTOR_COOLING[i].TURBINES, 1)
-    assert(cfv.valid(), "config: bad number of boilers/turbines for reactor " .. i)
 end
 
 ----------------------------------------
 -- log init
 ----------------------------------------
 
-log.init(config.LOG_PATH, config.LOG_MODE, config.LOG_DEBUG == true)
+log.init(config.LogPath, config.LogMode, config.LogDebug == true)
 
 log.info("========================================")
 log.info("BOOTING supervisor.startup " .. SUPERVISOR_VERSION)
@@ -102,8 +98,8 @@ local function main()
     ppm.mount_all()
 
     -- message authentication init
-    if type(config.AUTH_KEY) == "string" then
+    if type(config.AuthKey) == "string" then
-        network.init_mac(config.AUTH_KEY)
+        network.init_mac(config.AuthKey)
     end
 
     -- get modem

supervisor/supervisor.lua

@@ -2,8 +2,6 @@ local comms      = require("scada-common.comms")
 local log        = require("scada-common.log")
 local util       = require("scada-common.util")
 
-local config     = require("supervisor.config")
-
 local svsessions = require("supervisor.session.svsessions")
 
 local supervisor = {}
@@ -13,6 +11,77 @@ local DEVICE_TYPE = comms.DEVICE_TYPE
 local ESTABLISH_ACK = comms.ESTABLISH_ACK
 local MGMT_TYPE = comms.MGMT_TYPE
 
+---@type svr_config
+local config = {}
+
+supervisor.config = config
+
+-- load the supervisor configuration
+function supervisor.load_config()
+    if not settings.load("/supervisor.settings") then return false end
+
+    config.UnitCount = settings.get("UnitCount")
+    config.CoolingConfig = settings.get("CoolingConfig")
+    config.FacilityTankMode = settings.get("FacilityTankMode")
+    config.FacilityTankDefs = settings.get("FacilityTankDefs")
+
+    config.SVR_Channel = settings.get("SVR_Channel")
+    config.PLC_Channel = settings.get("PLC_Channel")
+    config.RTU_Channel = settings.get("RTU_Channel")
+    config.CRD_Channel = settings.get("CRD_Channel")
+    config.PKT_Channel = settings.get("PKT_Channel")
+
+    config.PLC_Timeout = settings.get("PLC_Timeout")
+    config.RTU_Timeout = settings.get("RTU_Timeout")
+    config.CRD_Timeout = settings.get("CRD_Timeout")
+    config.PKT_Timeout = settings.get("PKT_Timeout")
+
+    config.TrustedRange = settings.get("TrustedRange")
+    config.AuthKey = settings.get("AuthKey")
+
+    config.LogMode = settings.get("LogMode")
+    config.LogPath = settings.get("LogPath")
+    config.LogDebug = settings.get("LogDebug")
+
+    local cfv = util.new_validator()
+
+    cfv.assert_type_int(config.UnitCount)
+    cfv.assert_range(config.UnitCount, 1, 4)
+
+    cfv.assert_type_table(config.CoolingConfig)
+    cfv.assert_type_table(config.FacilityTankDefs)
+    cfv.assert_type_int(config.FacilityTankMode)
+    cfv.assert_range(config.FacilityTankMode, 0, 8)
+
+    cfv.assert_channel(config.SVR_Channel)
+    cfv.assert_channel(config.PLC_Channel)
+    cfv.assert_channel(config.RTU_Channel)
+    cfv.assert_channel(config.CRD_Channel)
+    cfv.assert_channel(config.PKT_Channel)
+
+    cfv.assert_type_num(config.PLC_Timeout)
+    cfv.assert_min(config.PLC_Timeout, 2)
+    cfv.assert_type_num(config.RTU_Timeout)
+    cfv.assert_min(config.RTU_Timeout, 2)
+    cfv.assert_type_num(config.CRD_Timeout)
+    cfv.assert_min(config.CRD_Timeout, 2)
+    cfv.assert_type_num(config.PKT_Timeout)
+    cfv.assert_min(config.PKT_Timeout, 2)
+
+    cfv.assert_type_num(config.TrustedRange)
+
+    if type(config.AuthKey) == "string" then
+        local len = string.len(config.AuthKey)
+        cfv.assert_eq(len == 0 or len >= 8, true)
+    end
+
+    cfv.assert_type_int(config.LogMode)
+    cfv.assert_type_str(config.LogPath)
+    cfv.assert_type_bool(config.LogDebug)
+
+    return cfv.valid()
+end
+
 -- supervisory controller communications
 ---@nodiscard
 ---@param _version string supervisor version
@@ -23,32 +92,23 @@ function supervisor.comms(_version, nic, fp_ok)
     -- print a log message to the terminal as long as the UI isn't running
     local function println(message) if not fp_ok then util.println_ts(message) end end
 
-    -- channel list from config
-    local svr_channel = config.SVR_CHANNEL
-    local plc_channel = config.PLC_CHANNEL
-    local rtu_channel = config.RTU_CHANNEL
-    local crd_channel = config.CRD_CHANNEL
-    local pkt_channel = config.PKT_CHANNEL
-
-    -- configuration data
-    local num_reactors = config.NUM_REACTORS
     ---@class sv_cooling_conf
-    local cooling_conf = { r_cool = config.REACTOR_COOLING, fac_tank_mode = config.FAC_TANK_MODE, fac_tank_defs = config.FAC_TANK_DEFS }
+    local cooling_conf = { r_cool = config.CoolingConfig, fac_tank_mode = config.FacilityTankMode, fac_tank_defs = config.FacilityTankDefs }
 
     local self = {
         last_est_acks = {}
     }
 
-    comms.set_trusted_range(config.TRUSTED_RANGE)
+    comms.set_trusted_range(config.TrustedRange)
 
     -- PRIVATE FUNCTIONS --
 
     -- configure modem channels
     nic.closeAll()
-    nic.open(svr_channel)
+    nic.open(config.SVR_Channel)
 
     -- pass modem, status, and config data to svsessions
-    svsessions.init(nic, fp_ok, num_reactors, cooling_conf)
+    svsessions.init(nic, fp_ok, config, cooling_conf)
 
     -- send an establish request response
     ---@param packet scada_packet
@@ -61,7 +121,7 @@ function supervisor.comms(_version, nic, fp_ok)
         m_pkt.make(MGMT_TYPE.ESTABLISH, { ack, data })
         s_pkt.make(packet.src_addr(), packet.seq_num() + 1, PROTOCOL.SCADA_MGMT, m_pkt.raw_sendable())
 
-        nic.transmit(packet.remote_channel(), svr_channel, s_pkt)
+        nic.transmit(packet.remote_channel(), config.SVR_Channel, s_pkt)
         self.last_est_acks[packet.src_addr()] = ack
     end
 
@@ -124,9 +184,9 @@ function supervisor.comms(_version, nic, fp_ok)
             local src_addr = packet.scada_frame.src_addr()
             local protocol = packet.scada_frame.protocol()
 
-            if l_chan ~= svr_channel then
+            if l_chan ~= config.SVR_Channel then
                 log.debug("received packet on unconfigured channel " .. l_chan, true)
-            elseif r_chan == plc_channel then
+            elseif r_chan == config.PLC_Channel then
                 -- look for an associated session
                 local session = svsessions.find_plc_session(src_addr)
 
@@ -201,7 +261,7 @@ function supervisor.comms(_version, nic, fp_ok)
                 else
                     log.debug(util.c("illegal packet type ", protocol, " on PLC channel"))
                 end
-            elseif r_chan == rtu_channel then
+            elseif r_chan == config.RTU_Channel then
                 -- look for an associated session
                 local session = svsessions.find_rtu_session(src_addr)
 
@@ -265,7 +325,7 @@ function supervisor.comms(_version, nic, fp_ok)
                 else
                     log.debug(util.c("illegal packet type ", protocol, " on RTU channel"))
                 end
-            elseif r_chan == crd_channel then
+            elseif r_chan == config.CRD_Channel then
                 -- look for an associated session
                 local session = svsessions.find_crd_session(src_addr)
 
@@ -299,7 +359,7 @@ function supervisor.comms(_version, nic, fp_ok)
                                     println(util.c("CRD (", firmware_v, ") [@", src_addr, "] \xbb connected"))
                                     log.info(util.c("CRD_ESTABLISH: coordinator (", firmware_v, ") [@", src_addr, "] connected with session ID ", s_id))
 
-                                    _send_establish(packet.scada_frame, ESTABLISH_ACK.ALLOW, { num_reactors, cooling_conf })
+                                    _send_establish(packet.scada_frame, ESTABLISH_ACK.ALLOW, { config.UnitCount, cooling_conf })
                                 else
                                     if last_ack ~= ESTABLISH_ACK.COLLISION then
                                         log.info("CRD_ESTABLISH: denied new coordinator [@" .. src_addr .. "] due to already being connected to another coordinator")
@@ -332,7 +392,7 @@ function supervisor.comms(_version, nic, fp_ok)
                 else
                     log.debug(util.c("illegal packet type ", protocol, " on coordinator channel"))
                 end
-            elseif r_chan == pkt_channel then
+            elseif r_chan == config.PKT_Channel then
                 -- look for an associated session
                 local session = svsessions.find_pdg_session(src_addr)