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#225 removed redundant checks on remote address, added clarity to log messages

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This commit is contained in:
Mikayla Fischler
2023-06-07 12:48:43 -04:00
parent 5ba06dcdaf
commit 15b071378c
6 changed files with 27 additions and 35 deletions
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17
rtu/rtu.lua
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@@ -341,8 +341,9 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
elseif rtu_state.linked and ((self.r_seq_num + 1) ~= packet.scada_frame.seq_num()) then
log.warning("sequence out-of-order: last = " .. self.r_seq_num .. ", new = " .. packet.scada_frame.seq_num())
return
elseif rtu_state.linked and src_addr ~= self.sv_addr then
log.debug("received packet from unknown computer " .. src_addr .. " while linked; channel in use by another system?")
elseif rtu_state.linked and (src_addr ~= self.sv_addr) then
log.debug("received packet from unknown computer " .. src_addr .. " while linked (expected " .. self.sv_addr ..
"); channel in use by another system?")
return
else
self.r_seq_num = packet.scada_frame.seq_num()
@@ -354,7 +355,7 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
-- handle packet
if protocol == PROTOCOL.MODBUS_TCP then
---@cast packet modbus_frame
if rtu_state.linked and (src_addr == self.sv_addr) then
if rtu_state.linked then
local return_code ---@type boolean
local reply ---@type modbus_packet
@@ -394,10 +395,8 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
end
public.send_modbus(reply)
elseif not rtu_state.linked then
log.debug("discarding MODBUS packet before linked")
else
log.debug("discarding MODBUS packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
log.debug("discarding MODBUS packet before linked")
end
elseif protocol == PROTOCOL.SCADA_MGMT then
---@cast packet mgmt_frame
@@ -436,7 +435,7 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
else
log.debug("SCADA_MGMT establish packet length mismatch")
end
elseif rtu_state.linked and (src_addr == self.sv_addr) then
elseif rtu_state.linked then
if packet.type == SCADA_MGMT_TYPE.KEEP_ALIVE then
-- keep alive request received, echo back
if packet.length == 1 and type(packet.data[1]) == "number" then
@@ -466,10 +465,8 @@ function rtu.comms(version, modem, rtu_channel, svr_channel, range, conn_watchdo
-- not supported
log.debug("received unsupported SCADA_MGMT message type " .. packet.type)
end
elseif not rtu_state.linked then
log.debug("discarding non-link SCADA_MGMT packet before linked")
else
log.debug("discarding non-link SCADA_MGMT packet from different supervisor (src_addr " .. src_addr .. " ≠ " .. self.sv_addr .. ")")
log.debug("discarding non-link SCADA_MGMT packet before linked")
end
else
-- should be unreachable assuming packet is from parse_packet()