#488 fixes to sequence number changes and auth packet data

supervisor/session/coordinator.lua

@@ -58,7 +58,8 @@ function coordinator.new_session(id, s_addr, i_seq_num, in_queue, out_queue, tim
     local self = {
         units = facility.get_units(),
         -- connection properties
-        seq_num = i_seq_num,
+        seq_num = i_seq_num + 2, -- next after the establish approval was sent
+        r_seq_num = i_seq_num + 1,
         connected = true,
         conn_watchdog = util.new_watchdog(timeout),
         establish_time = util.time_s(),
@@ -182,11 +183,11 @@ function coordinator.new_session(id, s_addr, i_seq_num, in_queue, out_queue, tim
     ---@param pkt mgmt_frame|crdn_frame
     local function _handle_packet(pkt)
         -- check sequence number
-        if self.seq_num ~= pkt.scada_frame.seq_num() then
-            log.warning(log_header .. "sequence out-of-order: last = " .. self.seq_num .. ", new = " .. pkt.scada_frame.seq_num())
+        if self.r_seq_num ~= pkt.scada_frame.seq_num() then
+            log.warning(log_header .. "sequence out-of-order: last = " .. self.r_seq_num .. ", new = " .. pkt.scada_frame.seq_num())
             return
         else
-            self.seq_num = pkt.scada_frame.seq_num() + 1
+            self.r_seq_num = pkt.scada_frame.seq_num() + 1
         end
 
         -- feed watchdog

supervisor/session/plc.lua

@@ -67,7 +67,8 @@ function plc.new_session(id, s_addr, i_seq_num, reactor_id, in_queue, out_queue,
         ramping_rate = false,
         auto_lock = false,
         -- connection properties
-        seq_num = i_seq_num,
+        seq_num = i_seq_num + 2, -- next after the establish approval was sent
+        r_seq_num = i_seq_num + 1,
         connected = true,
         received_struct = false,
         received_status_cache = false,
@@ -349,11 +350,11 @@ function plc.new_session(id, s_addr, i_seq_num, reactor_id, in_queue, out_queue,
     ---@param pkt mgmt_frame|rplc_frame
     local function _handle_packet(pkt)
         -- check sequence number
-        if self.seq_num ~= pkt.scada_frame.seq_num() then
-            log.warning(log_header .. "sequence out-of-order: last = " .. self.seq_num .. ", new = " .. pkt.scada_frame.seq_num())
+        if self.r_seq_num ~= pkt.scada_frame.seq_num() then
+            log.warning(log_header .. "sequence out-of-order: last = " .. self.r_seq_num .. ", new = " .. pkt.scada_frame.seq_num())
             return
         else
-            self.seq_num = pkt.scada_frame.seq_num() + 1
+            self.r_seq_num = pkt.scada_frame.seq_num() + 1
         end
 
         -- process packet

supervisor/session/pocket.lua

@@ -44,7 +44,8 @@ function pocket.new_session(id, s_addr, i_seq_num, in_queue, out_queue, timeout,
 
     local self = {
         -- connection properties
-        seq_num = i_seq_num,
+        seq_num = i_seq_num + 2, -- next after the establish approval was sent
+        r_seq_num = i_seq_num + 1,
         connected = true,
         conn_watchdog = util.new_watchdog(timeout),
         last_rtt = 0,
@@ -93,11 +94,11 @@ function pocket.new_session(id, s_addr, i_seq_num, in_queue, out_queue, timeout,
     ---@param pkt mgmt_frame
     local function _handle_packet(pkt)
         -- check sequence number
-        if self.seq_num ~= pkt.scada_frame.seq_num() then
-            log.warning(log_header .. "sequence out-of-order: last = " .. self.seq_num .. ", new = " .. pkt.scada_frame.seq_num())
+        if self.r_seq_num ~= pkt.scada_frame.seq_num() then
+            log.warning(log_header .. "sequence out-of-order: last = " .. self.r_seq_num .. ", new = " .. pkt.scada_frame.seq_num())
             return
         else
-            self.seq_num = pkt.scada_frame.seq_num() + 1
+            self.r_seq_num = pkt.scada_frame.seq_num() + 1
         end
 
         -- feed watchdog

supervisor/session/rtu.lua

@@ -52,7 +52,8 @@ function rtu.new_session(id, s_addr, i_seq_num, in_queue, out_queue, timeout, ad
         advert = advertisement,
         fac_units = facility.get_units(),
         -- connection properties
-        seq_num = i_seq_num,
+        seq_num = i_seq_num + 2, -- next after the establish approval was sent
+        r_seq_num = i_seq_num + 1,
         connected = true,
         conn_watchdog = util.new_watchdog(timeout),
         last_rtt = 0,
@@ -240,11 +241,11 @@ function rtu.new_session(id, s_addr, i_seq_num, in_queue, out_queue, timeout, ad
     ---@param pkt modbus_frame|mgmt_frame
     local function _handle_packet(pkt)
         -- check sequence number
-        if self.seq_num ~= pkt.scada_frame.seq_num() then
-            log.warning(log_header .. "sequence out-of-order: last = " .. self.seq_num .. ", new = " .. pkt.scada_frame.seq_num())
+        if self.r_seq_num ~= pkt.scada_frame.seq_num() then
+            log.warning(log_header .. "sequence out-of-order: last = " .. self.r_seq_num .. ", new = " .. pkt.scada_frame.seq_num())
             return
         else
-            self.seq_num = pkt.scada_frame.seq_num() + 1
+            self.r_seq_num = pkt.scada_frame.seq_num() + 1
         end
 
         -- feed watchdog

supervisor/session/svsessions.lua

@@ -274,7 +274,7 @@ end
 -- establish a new PLC session
 ---@nodiscard
 ---@param source_addr integer PLC computer ID
----@param i_seq_num integer initial sequence number to use next
+---@param i_seq_num integer initial (most recent) sequence number
 ---@param for_reactor integer unit ID
 ---@param version string PLC version
 ---@return integer|false session_id
@@ -324,7 +324,7 @@ end
 -- establish a new RTU gateway session
 ---@nodiscard
 ---@param source_addr integer RTU gateway computer ID
----@param i_seq_num integer initial sequence number to use next
+---@param i_seq_num integer initial (most recent) sequence number
 ---@param advertisement table RTU capability advertisement
 ---@param version string RTU gateway version
 ---@return integer session_id
@@ -365,7 +365,7 @@ end
 -- establish a new coordinator session
 ---@nodiscard
 ---@param source_addr integer coordinator computer ID
----@param i_seq_num integer initial sequence number to use next
+---@param i_seq_num integer initial (most recent) sequence number
 ---@param version string coordinator version
 ---@return integer|false session_id
 function svsessions.establish_crd_session(source_addr, i_seq_num, version)
@@ -410,7 +410,7 @@ end
 -- establish a new pocket diagnostics session
 ---@nodiscard
 ---@param source_addr integer pocket computer ID
----@param i_seq_num integer initial sequence number to use next
+---@param i_seq_num integer initial (most recent) sequence number
 ---@param version string pocket version
 ---@return integer|false session_id
 function svsessions.establish_pdg_session(source_addr, i_seq_num, version)

supervisor/supervisor.lua

@@ -197,7 +197,7 @@ function supervisor.comms(_version, nic, fp_ok)
         local r_chan    = packet.scada_frame.remote_channel()
         local src_addr  = packet.scada_frame.src_addr()
         local protocol  = packet.scada_frame.protocol()
-        local i_seq_num = packet.scada_frame.seq_num() + 1
+        local i_seq_num = packet.scada_frame.seq_num()
 
         if l_chan ~= config.SVR_Channel then
             log.debug("received packet on unconfigured channel " .. l_chan, true)